A ball screw is an ideal product that converts rotational motion into linear motion, or converts a linear motion into a rotational motion. Select custom machining ball screw, to identify titanium Hao machinery, professional quality assurance, because professional, so excellent! The ball screw is the most commonly used tools of mechanical transmission components and precision machinery, its main function is to convert rotary motion into linear motion, or torque into axial force repeatedly, both characteristics of high precision, high efficiency and reversibility. Because of its small friction resistance, ball screws are widely used in various industrial equipment and precision instruments!
There are many kinds of faults in the ball screw, and there is no fixed mode. Some fault is gradual failure, there must be a process of development, with the increasing use of time more and more serious; sometimes the sudden failure, generally do not have obvious signs of sudden, this failure is various unfavorable factors and external interaction generated. Therefore, the correct test to determine the cause of the real fault is the premise of fast and accurate maintenance.
1, ball screw, nut and support system clearance detection and repair
When a CNC machine tool reverse error and high positioning accuracy, unstable quadrant marks, the first to detect screw system there is no gap. Detection methods: indicator with the ball on the end of the center hole of screw, screw axial measurement, another piece of dialgauge measuring worktable. The rotation of the screw, observe the two block on the dial indicator shows, according to the change of different values confirm the fault location.
2 、 the detection and repair of the clearance of the screw bearing
If the dial indicator measuring screw in the screw forward and reverse rotation of the pointer no swing, that no screw movement. If the indicator pointer swing, indicating screw channeling phenomenon. The dial indicator measuring the maximum and minimum value difference is the screw axial distance. At this point, we will check whether the back bearing of the support bearing is locked, whether the bearing is worn out or not, whether the preload bearing washer is suitable or not. If the bearings are all right, just re - load the pre - loaded gasket. If the bearings are damaged, the bearings need to be replaced, re - loaded with pre - load washers, and then backed back. The axial movement of the lead screw mainly depends on the precision of the preload bearing gasket. The most ideal condition of the installation accuracy of the screw rod is that there is no positive and negative clearance, and the support bearing must have about 0.02mm interference.
3 、 the detection and maintenance of the gap between the two nut pairs of the ball screw
By inspection, if the fault is confirmed, it is not caused by the movement of the lead screw. It is necessary to consider whether the screw nut, the gap between the two, the detection of this situation basically with the detection of lead screw moving the same. Working table is connected with the dial indicator and the nut, forward and reverse rotation screw, detect the maximum clearance between a screw and a nut, and then adjusted.
4 、 inspection and maintenance of single nut pair
For single nut ball screws, the gap between the screw and nut pairs cannot be adjusted. If the lead screw nut is detected, there is a gap. First check the lead screw and nut thread arc whether worn, such as serious wear, must replace the whole set of lead screw nut.
If minor wear is detected, a larger diameter ball can be replaced to repair it. First of all, the maximum clearance of the screw nut pair is detected, converted to the increase of the ball diameter, and then fitted with the appropriate ball to reassemble. This kind of maintenance is complex and takes a long time and requires a high level of technology.
5, the nut flange and the table connected, there is no fixed gap
This problem can easily be neglected for a long time, reciprocating machine, screw Fala disc loose gap, check the gap in the top screw failure factors to exclude, in order to avoid detours in repair.
6, ball screw nut movement is not smooth, excessive noise and other failures maintenance
Ball screw nut movement is not smooth and noise is too large, mostly due to poor lubrication, but sometimes may be due to servo motor drive parameters are not adjusted properly caused.