Reducer and reducer bearing

The reducer is a component that transmits power. Its working principle is to reduce the number of revolutions and obtain greater torque by using the gear speed change device.

There are many kinds of reducers, which can be divided into gear reducers, worm reducers, planetary reducers and their combined reducers according to the transmission form, single-stage and multi-stage reducers according to the transmission quantity, cylindrical gear reducers, bevel gear reducers and bevel gear reducers according to the gear shape, and deployable, shunt and coaxial reducers according to the transmission mode.

1. Bearing of reducer

One 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 kinds of reducer bearings, including rolling bearings and cylindrical roller bearings.

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

2. Gear shaft

The combination of gear, shaft and bearing, the combination of pinion and shaft, is called gear shaft. This arrangement is used when the diameter of the gear is not closely related to the diameter of the shaft. If the shaft diameter is d and the gear root circle diameter is df, this arrangement should be selected when df-d ≤ 6-7mn. When df-d>6-7mn, the gear and shaft separation arrangement is selected, such as low-speed shaft and big gear. At this time, the gear and the shaft are connected by a circumferential fixed flat key, and the parts on the shaft are axially fixed by the shaft shoulder, shaft sleeve and bearing cover. Both shafts use deep groove ball bearings. This combination is used to withstand radial load and small axial load.

When the axial load is large, the combination of angular contact ball bearing, tapered roller bearing or deep groove ball bearing and thrust bearing should be selected. Use the thin oil splashed when the gear rotates to make the bearing smooth. The smooth oil from the oil pool in the case base flows into the groove on the surface of the auxiliary oil tank along the inner wall after splashing through the rotary gear on the inner wall of the case cover, and then flows into the inner groove of the bearing through the oil deflector. When the circumferential speed u of the gear immersed in oil is ≤ 2m/s, smooth grease bearing should be selected. In order to prevent the thin oil from splashing the smooth grease, oil baffle ring can be selected to separate it. To avoid loss of lubricating oil and external dust entering the box,

3. Box

The box is an important part of the reducer. It is the foundation of the transmission part and shall have the required strength and stiffness. The box is usually made of gray cast iron, and the cast steel box can also be used for heavy or impact load reducers. In order to simplify the process and reduce the cost, the reducer produced by the monomer can choose the box made of steel plate welding.

Grey cast iron has good casting function and vibration reduction function. To facilitate the loading and unloading of shafting components, the box is horizontally split along the axis. The upper cover and lower box are fixed together with bolts. The connecting bolts of the shell shall be as close to the shell hole as possible, and the boss close to the shell shall have a suitable supporting surface to place the connecting bolts, and ensure the wrench space required for tightening the bolts. To ensure satisfactory stiffness of the housing, support ribs are added near the bearing bores. In order to ensure the stability of the reducer on the foundation and reduce the processing area of the bottom of the box as much as possible, the bottom of the box usually does not choose a perfect plane