Integral motor spindle is a new technology in the field of CNC machine tools in recent years, which integrates the machine tool spindle and spindle motor. Together with linear motor technology and high-speed tool technology, it will push high-speed machining to a new era. Integral motor spindle is a set of components, which includes Integral motor spindle itself and its accessories: Integral motor spindle, high-frequency conversion device, oil mist lubricator, cooling device, built-in encoder and tool change device.

The technology integrated by integral motor spindle includes

High speed bearing technology: integral motor spindle usually adopts composite ceramic bearing, which is wear-resistant and heat-resistant, and its service life is several times that of traditional bearing; Sometimes, electromagnetic suspension bearing or hydrostatic bearing is also used. The inner and outer rings are not in contact, and the service life is unlimited in theory.

High speed motor technology: integral motor spindle is the product of the integration of motor and spindle. The rotor of motor is the rotating part of spindle. In theory, integral motor spindle can be regarded as a high-speed motor. The key technology is dynamic balance at high speed.

Lubrication: regular and quantitative oil-gas lubrication is generally adopted for the lubrication of integral motor spindle; Grease lubrication can also be used, but the corresponding speed should be decreased. Regular lubrication is to inject oil every certain time interval. Quantitative lubrication is to accurately control the amount of lubricating oil each time through a device called quantitative valve. Oil air lubrication refers to that the lubricating oil is blown into the ceramic bearing under the carrying of compressed air. Oil quantity control is very important, if too little, it cannot play the role of lubrication; if too much, heat will be generated due to the resistance of oil when the bearing rotates at high speed.

Cooling device: in order to dissipate heat to the high-speed integral motor spindle as soon as possible, circulating coolant is usually supplied to the outer wall of the integral motor spindle. 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 thread tapping, a pulse encoder is built in the integral motor spindle to realize accurate phase angle control and coordination with feed.

Automatic tool change device: in order to be applied to the CNC machining center, the integral motor spindle is equipped with an automatic tool change device, including disc spring, tool pulling oil cylinder, etc; Clamping mode of high-speed cutting tools which are the well known BT and ISO cutting tools have been proved not to be suitable for high-speed machining. In this case, HSK, SKI and other high-speed tools appear.

High frequency conversion device: to realize the speed of tens of thousands or even hundreds of thousands of revolutions per minute of the integral motor spindle, a high frequency conversion device must be used to drive the built-in high-speed motor of the integral motor spindle, and the output frequency of the frequency converter must reach thousands or thousands of Hertz.