Basic knowledge of reducers you may want to know

In the large family of mechanical transmission, reducers are widely used in various systems that require deceleration in general machinery and industrial industries due to their abundant advantages such as high transmission efficiency, wide deceleration range, and high precision. It can be said that reducers are well-deserved core products in the transmission industry.

So, what is a reducer? How are reducers generally classified? What is the internal structure of a reducer? What are the structural characteristics?

In this article, SGR will take you to learn the basic knowledge of reducers.

 (1) What is a reducer?
The reducer is an independent closed transmission device between the prime mover and the working machine, which is used to reduce the speed and increase the torque to meet the work requirements. In some cases, it is also used to increase the speed, which is called a speed increaser. When selecting a reducer, you should compare the outer dimensions, transmission efficiency, load capacity, quality, price, etc. of different types and varieties of reducers based on the selection conditions, technical parameters of the working machine, performance of the power machine, economy, and other factors, and select the most suitable reducer.

In general, a reducer is a relatively precise machine, and its purpose is to reduce the speed and increase the torque in transmission machinery.

 (2) How are reducers generally classified?

According to the different transmission forms, reducers can be divided into gear reducers, worm reducers, and planetary reducers. These three types of reducers are more common in actual use.

Gear reducers mainly include cylindrical gear reducers, bevel gear reducers, and cylindrical-bevel gear reducers. Gear reducers are characterized by high transmission efficiency, long service life, and easy maintenance, so they have a very wide range of applications.

As a traditional transmission device, the worm gear reducer has a worm gear inside and an involute tooth profile. The worm gear reducer has the advantages of compact structure, light size, high efficiency, easy installation, flexibility, superior performance, large transmission ratio, high torque, high overload capacity, and smooth operation.

Planetary gear reducer, also known as planetary reducer, or servo reducer, has the characteristics of small size, lightweight, high load-bearing capacity, long service life, smooth operation, and low noise. Planetary gear reducer is a new type of reducer with wide versatility in the world.

 (3) What is the internal structure of the reducer? What are its characteristics?

The main structure of the reducer includes gear, shaft, and bearing combination.

The pinion and shaft are made into one piece, which is called a gear shaft. This structure is used when the diameter of the gear is not closely related to the diameter of the shaft. If the diameter of the shaft is d and the diameter of the gear root circle is df, this structure should be used when df-d ≤6~7mn. When df-d>6~7mn, the structure in which the gear and shaft are separated into two parts is used, such as the low-speed shaft and the large gear.

The bearing is lubricated by the thin oil splashed when the gear rotates. The lubricating oil in the oil pool in the box seat is splashed by the rotating gear onto the inner wall of the box cover, flows along the inner wall to the groove of the dividing box surface, and then flows into the bearing through the oil guide groove. When the peripheral speed of the oil-immersed gear is us2m/s, the bearing should be lubricated with grease. To avoid the thin oil that may splash and wash away the grease, an oil retaining ring can be used to separate it. To prevent the loss of lubricating oil and the entry of external dust into the box, a sealing element is installed between the bearing end cover and the extended shaft.

In the reducer, the shaft is generally divided into an input shaft and an output shaft. The input shaft inputs power and bears a certain torque and bending moment. Considering the strength of the gear, the strength and rigidity of the shaft, the gear, and the shaft are usually made into one piece. The output shaft outputs power and bears a larger torque and bending moment. The parts on the shaft are positioned circumferentially and axially with flat keys and steps.

The housing of the reducer is an important component of the reducer. It is the base of the transmission parts and should have sufficient strength and rigidity.

The housing is usually made of gray cast iron. For heavy-loaded or impact-loaded reducers, cast steel housings can also be used. For reducers produced in a single unit, in order to simplify the process and reduce costs, steel plate welded housings can be used.