Reducer and Reducer Bearings

Reducer is a kind of component that transmits power, and its working principle is to use the speed converter of the gear to reduce the number of turns and obtain a large torque.

There are many varieties of reducers, according to the type of transmission can be divided into gear reducers, worm reducers and planetary reducers and their combination of reducers, according to the number of transmission can be divided into single-stage and multi-stage reducers, according to the shape of the gear can be divided into cylindrical gear reducer, bevel gear reducer and cone a cylindrical gear reducer, according to the way of transmission settlement can be divided into unfolded, shunt and coaxial reducer.

 

A part of the reducer is the reducer bearing, which supports the rotating gear shaft or connecting rod. It is precisely because of the existence of the reducer bearing that the reducer can operate and work normally. There are many types of reducer bearings, commonly used are rolling bearings and cylindrical roller bearings.

The reducer is mainly composed of transmission parts, shaft, bearing, box and its accessories. Its basic layout has three factors: box, gear, shaft and bearing combination, reducer accessories.

The combination of gear, shaft and bearing, the pinion and the shaft are made into one, called the gear shaft. This arrangement 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, the diameter of the root circle of the gear For df, this layout should be selected when df-d≤6～7mn. And when df-d>6～7mn, choose the layout of gear and shaft separated into two parts, such as low-speed shaft and large gear. At this moment, the gear and the shaft are connected with the circumferentially fixed flat key, and the parts on the shaft are axially fixed by the shaft shoulder, the shaft sleeve and the bearing cover. Both shafts use deep groove ball bearings. This combination is used to accept radial loads and minor axial loads.

When the axial load is large, a combination of angular ball bearings, tapered roller bearings or deep groove ball bearings and thrust bearings should be used. Bearings are made smooth using the thin oil splashed when the gear rotates. The smooth oil from the oil pool in the box seat is splashed by the rotating gears on the inner wall of the box cover, flows along the inner wall to the groove of the sub-tank surface, and flows into the bearing through the oil guide groove. When the circumferential speed of the oil immersion gearυ≤2m/s, smooth grease smooth bearings should be selected, in order to avoid the dilute oil that can splash away the smooth grease, the oil retaining ring can be selected to separate it. To avoid smooth oil loss and external dust entering the box, a sealing element is installed between the bearing end cover and the extended shaft.

The box, the box is an important component of the reducer. It is the base of the transmission part and should have the strength and stiffness that meets the requirements. The box is usually made of gray cast iron, and the cast steel box can also be used for heavy duty or shock load reducers. In order to simplify the process and reduce costs, the reducer produced by the single body can be selected as a box welded with steel plate.

Grey cast iron has a good casting function and vibration damping function. In order to facilitate the equipment and disassembly of the shafting components, the boxing is horizontally split along the axis line. The upper lid and the lower box are bolted together. The coupling bolts of the housing should be as close as possible to the housing bore, and the boss next to the housing should have a suitable support surface to place the joint bolts and ensure the wrench space required when tightening the bolts. To ensure that the housing has a satisfactory stiffness, support ribs are added adjacent to the bearing bore. In order to ensure the stability of the reducer on the basis and to reduce the machining area of the box base plane as much as possible, the box base is usually not selected for a perfect plane.

 

The application of the bearing in the reducer

Deep groove ball bearings: mainly used in cycloidal reducer, stepless transmission input shaft part, gear reducer with motor connection flange when the connection shaft, input shaft part, worm gear gear reducer worm gear part;

Eccentric cylindrical roller bearings: for the input shaft or motor shaft and the cycloidal wheel;

Tapered roller bearings: mainly used in the gear reducer's transmission tooth shaft and output shaft.