In the bearing oil supply system, except for coarse and fine filtration, all the other components can protect the static bearing.The oil supply system is improved on the basis of the original system.The outlet behind the throttle plate is connected to the pressure relay and the pressure gauge (originally in front of the accumulator) so that the operator can see the cavity pressure and pressure.When the pressure difference is greater than a certain value, in order to stop immediately, so as not to lock the bearing bush.For example, the pressure is 2mpa, and the pressure is 1.2 ~ 1.6mpa. If the pressure is lower than 1.2mpa, the machine will stop.
Add digital detection devices:
There is a gap of 0.04 ~ 0.05mm between the wear-resistant electrode static bearing spindle and the bearing bush. The oil in the gap has a certain resistance value. The size of the gap can be known by detecting the change of this resistance value.Take the spindle as one pole and the bearing bush as another pole to measure the change of resistance value.This signal is processed and sent to the photoelectric alarm and control system amplifier to control the start and stop of the spindle motor to avoid friction between the shaft and the tile
The film feedback throttle bearing rigidity is very large, but the machine often appears in the operation of the tile, drawing, pressure drop and other phenomena.Film feedback is the most critical film, in practice, the bearing bush is locked, the main reason is: film plastic deformation;Slow feedback.When the external load mutation, the film has not yet reacted, the axis and tile has been friction;Film fatigue.The long service time and fatigue deformation of the film are equivalent to changing the feedback parameters.
Increasing the thickness of the film and switching to some fatigue resistant materials can get good results.Generally, the method of rigid film, pre-loading and gap reservation is adopted.The specific method of bearing is: change the 1.4mm thick film to 4mm thick rigid film, pad the lower cavity with 0.05mm thick tin foil, so that the spindle is adjusted to a position 0.05mm higher than the ideal position.The purpose is to return the spindle to the ideal center when it is under force (grinding wheel weight, cutting force).
But for the average mobile phone, when these conditions are not available, the empirical method can be roughly checked.(1) Observation method.Visually observe the bearing, the inner and outer raceway should be free from spalling marks and serious wear, and should be in the shape of an arc groove;All rolling surfaces shall be free from spots, cracks and peeling.Cage should not loose, no damage, not worn through, and rolling body clearance is not large.(2) Feel method.The clearance between inner and outer seat ring of normal bearing and rolling body is 0.005 ~ 0.010 mm.For bearings that have been used for one stage, when the inner seat ring is held by fingers for axial shaking, there should be no obvious sound.(3) Rotation method.With one hand clamping the inner seat ring of the bearing, with the other hand turning the outer seat ring, the bearing should be able to rotate flexibly, and should not feel the radial shaking.During the inspection, the above three empirical methods should be combined to make a correct judgment on the technical state of the rolling bearing.For tapered roller bearings, also observe whether the rolling body is located in the middle of the outer seat ring. If there is a forward movement, it should not exceed 1.5 mm.