-. Is the motor shaft traversing problem causing the bearing to overheat?
1, motor shaft traversal problems: general motors use more often deep groove ball bearing and cylindrical roller bearing . During installation, one end is axial positioned and the other end is axial floating. bearings move. First of all, you should check how the axial positioning is done? Whether the positioning is reliable. If reliable, for deep groove ball bearings, its axial momentum should be its axial clearance. Generally not too big. But it depends on the chosen radial clearance. For cylindrical stick bearings, for N and NU series, they cannot be used as positioning bearings. If they are used for positioning, they must be too large.
2 and 3 shaft trolling bearings. If the positioning bearings bear excessive axial load, the bearings will burn. Therefore, when choosing a positioning bearing, you should check how large the axial load is. Can the bearing be withstand it? If it is a cylindrical rod bearing of NJ series, this axial load is completely borne by the sliding part, so it cannot be done. For deep groove ball bearings, its axial capacity is more than one-quarter of the radial direction, and it is different for different bearings.
2. If deep groove ball bearing is used, is it necessary to fix one end bearing and the shaft to the end cover to limit the shaft to move? Nowadays, many shafts can move back and forth, relying on a corrugated gasket to pad, but they can still move
Axial system generally requires axial positioning. Therefore, there will be a section as the positioning end and one end as the moving end.
3. is padded by a wave spring. The wave spring is not used for positioning, but for adding axial preload. Therefore, for the cross-positioned motor, there must be this axial twitch caused by spring washer . If you want to control it, you should do a traditional positioning end and a non-positioning end. Then, add a spring washer to the segment, and it’s fine!
4. In the low-power DC brushed motor , one end uses ball bearings and the other end uses spherical oil-containing bearings. How to use ball bearings and tightness to cooperate with the shaft and bearing chamber for such a structure. (Shaft diameter 8mm, bearing thickness 8mm, two bearing gears are about 90mm, motor noise requirements are very high)
Generally speaking, j5\6 is used for the inner ring, and H7 is used for the outer ring, but this is not absolute. In addition, in terms of controlling motor noise, special clearance and grease have been needed to control the bearing (if the noise requirements are very high). play can choose a smaller one, don't be too small, otherwise it will be locked. Choose a lower viscosity grease.
5. What is the situation when the bearing runs the outer ring?
is divided into two situations: first, the aluminum bearing chamber is used, the second is a general cast iron, or other iron bearing chambers.
For the first, since the expansion coefficient of aluminum is twice that of iron, the correct coordination used during installation will become loose after the temperature rises, and the running lap will also occur. There are two ways: First, speed up cooperation during installation. This method is not recommended. Although it can be solved, it is more annoying when installing, so the workers will call it. 2. Use a rubber ring and open a groove in the bearing chamber. The groove depth is 30.8 times the thickness of the rubber ring and 1.4 times the width. That's fine.
The second item, iron bearing chamber, it is recommended to check the coordination of the bearing chamber. This problem is much simpler than the above, and most of the cooperation is loose!
6. According to some bearing information, the degree of cooperation between the outer ring of the bearing and the bearing chamber is that the outer ring of the bearing can peristaltic in the bearing chamber, which will cause the outer ring of the bearing to wear uniformly and extend the service life of the bearing?
Peristalsis refers to axial peristalsis, which is intended to absorb axial expansion. (It is definitely not a circumferential creeping, the circumferential flexural flexure is definitely bad, it destroys the rolling state of the bearing.) But the statement that the outer ring is subject to uniform wear. The purpose of creeping is not to wear. After wear, the relative position and load of the bearing will change, which may not be good. If peristaltic wear is good, there is no need to invent the axially elongated bearings that can be adjusted.
