Mechanical processing machinery parts and auxiliary equipment is an important part of CNC machine tools. Among them, the mechanical parts mainly include: machine tool spindle parts, ball screw nut, rail and so on. The auxiliary devices are mainly include: CNC indexing head, automatic tool change device, hydraulic pressure system and cooling lubrication device. Therefore, their daily maintenance and maintenance of CNC machine tools is one of the maintenance and care work.

First, the mechanical part of the maintenance and repair

CNC machine maintenance and maintenance of mechanical parts include: machine tool spindle parts, feed drive, rails and other maintenance and care.

1. Spindle parts maintenance and care

The main shaft component is an important component in the mechanical part of CNC machine tool. It mainly consists of spindle, bearing, quasi-stop spindle, automatic clamping and chip removal device. CNC machine tool spindle lubrication, cooling and sealing machine is the use and maintenance of several issues worth noting.

First of all, a good lubrication effect, can reduce the bearing operating temperature and extend the service life; To this end, in operation should be noted that: low speed, the use of grease, oil circulating lubrication; high speed oil mist, oil and gas lubrication. However, the use of grease lubrication, the main bearing seal is usually the volume of 10% of the bearing space, should not be free to fill, because too much oil, will exacerbate the spindle fever. For the oil circulation lubrication, in operation to be used every day to check the spindle lubrication thermostat tank to see if the oil is sufficient, if the amount of oil is not enough, you should promptly add lubricant; the same time, pay attention to check the lubricant temperature range is appropriate.

In order to ensure that the spindle has good lubrication, friction and heat to reduce, while the spindle assembly can take the heat away, usually using a circulating lubrication system, with a strong hydraulic pump lubrication, the use of oil temperature controller to control the fuel tank temperature. High-grade CNC machine tool spindle bearings with a high-grade grease sealed lubrication, plus a grease can be used for 7 to 10 years. The new type of lubrication cooling not only reduces bearing temperature, but also reduce the temperature difference between the inner and outer bearing, to ensure that the spindle thermal deformation is small.

Common spindle lubrication in two ways, oil and gas lubrication is similar to the oil mist lubrication, but the oil mist lubrication is continuous supply of oil mist, while the oil and gas lubrication is time and quantitative oil mist into the bearing clearance, so both to achieve Oil mist lubrication, but also to avoid too much oil mist and pollute the surrounding air. Injection lubrication method is to use a larger flow of constant temperature oil (each bearing 3 ~ 4L / min) injection to the spindle bearings, in order to achieve the purpose of lubrication, cooling. The larger flow injection oil here must rely on the discharge pump forced discharge, rather than a natural return. At the same time, but also to use a dedicated large-capacity high-precision temperature tank, oil temperature change control at ± 0.5 ℃.

2. Spindle parts cooling is mainly to reduce bearing fever, effective control of heat-based.

Cylindrical external gear, respectively, and the two ends of the sleeve fixed ring gear meshing, the number of teeth were Z1, Z2, and a difference of one tooth. Adjustment, the first take off the ring gear, so that the two nuts relative to the sleeve in the same direction are rotating a tooth, and then insert the ring gear, the two nuts will have a relative angular displacement, the axial displacement is: Where Z1, Z2 is the number of teeth of the gear, Ph is the lead of the ball screw.