In the last article, we talked about how to judge the bearing failure of the engraving machine. Now let's talk about what to do if the bearing of the engraving machine fails?
1. Remove the front and rear end caps and the front and rear nuts of the engraving machine.
2. Push out the main shaft, rear bearing seat, linear bearing and other accessories by force backward from the front end of the shaft.
3. Front and rear bearing washers.
(1) The front and rear bearings of the electric spindle are paired in series with DT.
(2) According to the direction of the axial force on the bearing, support the inner sleeve and press down the outer sleeve by hand (the force is roughly the same as the preload force of the spring on the bearing). There are two ways to adjust the gap of the washer. The first is to replace the bearing and the upper and lower positions of the bearing. The second is to grind the height of the washer. The washer is ground using the figure-8 grinding method. At the same time, the position of the washer is rotated to ensure that the parallel difference of the washer is within 2um. If the force is uniform, the preload of the two sets of bearings is uniform.
(3) If the matched bearing is selected, the size difference of the inner and outer washers shall be within 2mm, the parallel difference of the washers shall be within 2mm, and the bearings shall be installed in pairs according to the V-shaped mark on the outer diameter.
(4) The long-term use of the preload spring will cause fatigue and reduce the elastic force; the preload on the bearing will decrease, which will affect the accuracy and life of the electric spindle. At this time, a new spring of the same specification should be replaced.
(5) If the washer is not properly equipped, the load of one set of the two sets of bearings is small, and the load of the other set is too large, the bearing will be unevenly stressed, which will generate heat, which will seriously affect the service life. The preload load on the bearing is uniform.
4. To clean the bearing, the outer sleeve slopes downward (or the inner sleeve slope upward) to rotate and clean (in clean gasoline). The bearing should be cleaned more than twice. After cleaning the bearing, the upper and lower positions of the bearing cannot be misplaced.
5. Before installing the bearing, the bearing, the inner hole of the shaft shell, and the main shaft are first lubricated with oil (special lubricating oil for the electric spindle). One is to facilitate the installation, and the other is to ensure the lubrication of the bearing in the initial stage of the electric spindle.
6. After cleaning other parts on the shaft, the bearing should be dried naturally after cleaning, and it is strictly forbidden to dry it with high-pressure gas.
7. Install the rear bearing first, tighten the nut, fix the spring on the bearing seat with butter, and the spring gland cannot be misplaced.
8. Assemble the front end bearing and fix the front end cover to preload the bearing jacket. (A special sleeve should be used to assemble the bearing, and the sleeve should be machined with a nylon bar. The shape is as follows: the D end is smaller than the bearing outer diameter, and the d end is larger than the bearing inner diameter)
9. Tighten the front nuts and install the front and rear end caps. When installing the rear end caps, pay attention to the position of the air inlet holes. The sealing rings of the air inlet holes, water inlet holes and water outlet holes should be intact and placed in the correct position.
10. After the front and rear bearings are installed, push the main shaft forward from the rear end of the electric main shaft in place, and push the linear bearing in place at the same time.
11. After the electric spindle is installed, check whether the spindle is installed in place (use the wrench to push the spindle forward, the spindle will move forward, and it will bounce back immediately if you release it.
How to maintain the bearing of the engraving machine?
1.The problem of the quality of the main shaft of the engraving machine, that is to say, the quality of the main shaft itself is not good enough, which leads to the damage of the bearing. Bearings of poor quality are used. When the spindle of the engraving machine is running at a high speed, the life is shortened, and it is easy to damage it.
2. The engraving spindle cooling system has no effect. The main shaft of the engraving machine is water-cooled with a water circulation system. If the temporary water circulation is not good, or the boiling water circulation may be forgotten, the thermal expansion effect will occur for a long time, resulting in increased friction and damage to the bearing.
3.It is related to the detailed operation of the engraving machine. Some of the spindles start to engrave before the speed of the spindle has reached, which will easily cause the damage of the bearing. Some customers have different resistances of the engraving materials during the engraving process. If the speed is not adjusted in time, the spindle of the engraving machine will be damaged. .
4. The water-cooled spindle must be protected from freezing in winter. It is not surprising that the water thaws in the cold winter and causes the pipeline to rupture. The spindle of the engraving machine will also be frostbitten.
The above is about the handling and maintenance of the bearing fault of the engraving machine. I hope it will be helpful to everyone. Pay attention to Superstar CNC to learn more about the engraving machine~