AC Motor Electric Spindle

Electric spindle is a new technology that has emerged in the field of CNC machine tools in recent years that integrates machine tool spindles and spindle motors. Together with linear motor technology and high-speed tool technology, it will push high-speed machining into a new era. The electric spindle is a set of components, which includes the electric spindle itself and its accessories: electric spindle, high-frequency conversion device, oil mist lubricator, cooling device, built-in encoder, and tool change device.
Technology integrated into the electric spindle:
High-speed bearing technology: Electric spindles usually use composite ceramic bearings, which are wear-resistant and heat-resistant, and have a lifespan several times that of traditional bearings; sometimes electromagnetic suspension bearings or hydrostatic bearings are also used, and the inner and outer rings do not come into contact, so theoretically they have unlimited lifespan;
High-speed motor technology: The electric spindle is the product of the fusion of the motor and the spindle. The rotor of the motor is the rotating part of the spindle. Theoretically, the electric spindle can be regarded as a high-speed motor. The key technology is dynamic balancing at high speed;
Lubrication: The lubrication of the electric spindle generally uses regular and quantitative oil and gas lubrication; grease lubrication can also be used, but the corresponding speed must be reduced. The so-called timing means to inject oil at certain intervals. The so-called quantitative control is to accurately control the amount of lubricating oil each time through a device called a quantitative valve. Oil-air lubrication refers to the lubricating oil being blown into the ceramic bearings by compressed air. Oil quantity control is very important. If it is too little, it will not provide lubrication; if it is too much, the bearing will generate heat due to the resistance of the oil when the bearing rotates at high speed. Cooling device: In order to dissipate heat to the high-speed running electric spindle as quickly as possible, the outer wall of the electric spindle is usually circulated with circulating coolant. The function of the cooling device is to maintain the temperature of the coolant.
Built-in pulse encoder: In order to realize automatic tool change and rigid tapping, the electric spindle has a built-in pulse encoder to achieve accurate phase angle control and coordination with feed.
Automatic tool changer: In order to be used in machining centers, the electric spindle is equipped with an automatic tool changer, including disc springs, broach cylinders, etc.;
How to install high-speed tools: The widely familiar BT and ISO tools have been proven to be unsuitable for high-speed machining. In this case, high-speed tools such as HSK and SKI appeared.
High-frequency frequency conversion device: To achieve tens of thousands or even hundreds of thousands of revolutions per minute of the electric spindle, a high-frequency frequency conversion device must be used to drive the built-in high-speed motor of the electric spindle. The output frequency of the frequency converter must reach thousands or several kilohertz. .