Be sure to pay attention to your application when choosing the motorized spindle, the interface of different application situations is different, in addition, be sure to find out your power requirements, and the corresponding speed under this power, this is very critical, because the same is 1 kW, in 1000 rpm and 10000 rpm requirements of the motorized spindle shape size is very different, so the working conditions must be accurate. The other reminder, the tool interface must be clear, this is also a principle, in general, the BT50 interface speed can only be used in 8000 RPM of the main shaft, the BT40 interface can be used in 18000 RPM of the main shaft, if the higher speed, the tool interface needs to select the corresponding HSK and other high-speed tool interface, CNC milling spindle with ER spring chuck or SD spring chuck is also allowed to use high speed.
The spindle for grinding is usually a motor designed with constant torque. The relation between high speed, power and voltage of motor is equal ratio. Because the relationship between torque and current is linear, it is called constant torque motor. The design of the motorized spindle for grinding generally takes into account the small speed range, usually 80%-100% of the rotational speed, and also takes into account the allowable linear speed of the grinding wheel. Therefore, it can not be used high speed and small grinding wheel and low speed and large grinding wheel.
In addition, due to the close rotation speed of the spindle, users can choose different grinding requirements, in order to achieve greater and better performance of the main shaft capacity and efficiency potential. The main shaft of milling and machining center usually has constant torque section and constant power section in the design to meet the cutting needs of wide speed range, low speed requires large torque heavy cutting, high speed requires a certain power precision cutting, so the motor system is quite different from the grinding spindle and so on. Moreover, the motor parameter system of the grinding spindle is usually marked with S6 working system, S6-40%、S6-60% and so on, which can not be separated from the working characteristics of grinding. The grinding beat of a workpiece usually includes several steps, such as fast feed, grinding, cutting back, grinding wheel, etc. One is related to the motor working system, the other is related to the overload capacity of the motor. The marking S6 the system power indicates that the motor can be overloaded in a short time within 30 s~120 s to the power system, and the long-term use can only be used according to the S1 system. This is not very similar to other motorized spindle, it must be noted.
Spindle is a new technology which combines spindle and spindle motor in the field of CNC machine tools. It combines with linear motor technology and high speed tool technology to push high speed machining to a new era. The motorized spindle is a set of components, which includes the motorized spindle itself and its accessories: motorized spindle, high frequency frequency conversion device, oil mist lubricator, cooling device, built-in encoder, tool changing device, etc. The rotor of the motor is directly used as the spindle of the machine tool, and the shell of the spindle unit is the motor seat, and with other parts, the integration of the motor and the spindle of the machine tool is realized.
Because the motorized spindle integrates the motor into the spindle unit, and the speed is very high, a large amount of heat will be generated during operation, which will cause the temperature rise of the motorized spindle, which will make the thermal and dynamic characteristics of the motorized spindle worse, thus affecting the normal operation of the motorized spindle. Therefore, some measures must be taken to control the temperature of the main axis so that it is constant within a certain value. At present, the machine tool generally adopts the method of forced circulating oil cooling to cool the stator and spindle bearing of the motorized spindle, that is, the cooling oil passing through the oil cooling device is forced to circulate outside the spindle stator and outside the spindle bearing to take away the heat generated by the high speed rotation of the spindle. In addition, in order to reduce the heating of spindle bearings, the spindle bearings must be lubricated reasonably.
Post time: May-20-2020