Electric spindleThe bearings generate a large amount of heat at high speeds and cause the temperature of the spindle to rise. The cutting tool installed at the end of the electric spindle also generates a large amount of heat during high-speed cutting, so the spindle is operated during the operation process. The issue of heat dissipation has attracted widespread attention, and Star Wheel believes that heat dissipation must be considered in the design of electric spindle structures.

During the high-speed operation of the electric spindle motor, internal power losses (including mechanical and electrical losses) cause the motor to heat up. Due to the installation of the electric spindle motor in the spindle unit housing, the spindle motor cannot directly use a fan for heat dissipation, and the natural heat dissipation conditions are also poor. The survey results indicate that when the motor rotates at high speed, the working temperature of the motor rotor reaches 140-160 ° C, and the stator temperature also reaches 45-85 ° C. The heat generated by the motor is directly transferred to the spindle, resulting in thermal deformation and machining errors of the spindle.

The purpose of the electric spindle cooling circuit is to maintain a constant spindle temperature, which is independent of the spindle speed. Therefore, it can prevent the extension of the spindle front end and protect the spindle bearings, so that the accuracy of the spindle is not affected by motor heating. The cooling circuit of the electric motor is mainly located in the electric motor. The cooling of the stator allows the temperature of the motor to be controlled by controlling the temperature of the stator to a lower range. The cooling method is to use external circulating water coolant to forcibly cool the motor stator, in order to enhance the external heat dissipation capability of the motor and keep the housing of the spindle components at room temperature; Tool cooling is an optional component, and external cooling or internal holes can be freely selected. Very cool, or both inside and outside. When cooled through the inner hole of the tool, the coolant passes through the middle hole of the rotary distributor under high pressure and opens the check valve to pop out from the middle hole of the handle (including the cutter).

It is very necessary to take heat dissipation measures. If the temperature is too high, it will directly affect the normal operation of the electric spindle. Therefore, during the operation of the electric spindle, it is necessary to pay attention to the temperature of the electric spindle and find that the heat dissipation is not good. To implement cooling measures, it is best to report the problem to the manufacturer in a timely manner, and professional technicians will solve it for you.

Reduce the heating of high-speed motor bearings:

Due to the difficulty in ensuring the quality of the selected rubber seal, it is usually the main cause of bearing heating. For motors with IP23 protection level, please consider using rubber seals on the cover plate instead of labyrinth seals. For motors with IP44 or higher, high-quality rubber seals must be used and bearings must be raised as much as possible. The smoothness of the friction contact surface between the outer cover and the rubber sealing ring reduces the friction coefficient and minimizes the heat generated by friction. High speed motor bearings are usually lubricated with grease, while bipolar motors should use high-speed motor specific grease. During the normal use of the motor, the bearings should be cleaned regularly and the lubricating grease in the bearing chamber should be replaced to prevent the grease from aging and hardening. Generate noise, causing the bearings to heat up and accelerate bearing wear. It should also be noted that the amount of lubricating grease may not be as good as possible. The amount of lubricating grease for bipolar high-speed motors should be small, the frequency of replacement should be higher, and waste oil should be discharged in a timely manner. It depends on the power of the motor and the weight of the rotor. Some motor users may not be able to replace the lubricating grease in a timely manner, or the amount of lubricating grease added may cause the bearings to heat up, burn out, and lock.