Linear motors are also known as putter motors. The most commonly used linear motor types are flat-panel linear motors, U-slot linear motors and cylindrical linear motors. Is a power transmission directly into a linear motion mechanical power of the power transmission device. It can save a lot of intermediate drive mechanism to speed up the system to reflect the speed and improve system accuracy, a linear motor application system is not only a good performance of the linear motor, but also must be safe and reliable conditions to achieve technical and economic requirements of the control system The With the development of automatic control technology and microcomputer technology, the control method of linear motor is more and more.
     The following examples of linear motor control technology applications:
     1 piston turning CNC system
     In the machine feed system, the use of linear motor direct drive and the original rotation of the motor drive is the biggest difference is to cancel the motor from the table (carriage) between the mechanical transmission link, the machine feed chain length is reduced to zero , So this transmission is also known as "zero drive". It is precisely because of this "zero drive" approach, bringing the original rotating motor drive can not achieve the performance indicators and advantages. First, high-speed response. As the system directly to cancel some of the response time constant large mechanical transmission parts (such as screw, etc.), so that the whole closed-loop control system greatly improved dynamic response performance, the reaction is extremely sensitive and fast. Second, the high precision. The linear drive system eliminates the transmission gap and error due to the screw mechanism and other mechanical mechanisms, reducing the tracking error caused by the hysteresis of the drive system during interpolation. Through the linear position detection feedback control, you can greatly improve the positioning accuracy of the machine. Linear motion mechanism with linear motor has been successfully applied in CNC turning and grinding of special-shaped cross-section workpiece because of its fast response and high precision. For the non-circular cross-section parts with the largest output, the non-circular cutting research center of the National Defense Science and Technology University has developed a high frequency loudspeaker NC feed unit based on linear motor. When used in CNC piston machine, the table size is 600 mm × 320 mm, the stroke is 100 mm, the maximum thrust is 160 N, the maximum acceleration is up to 13 g. As the linear motor mover and workstations have been fixed together, so only closed-loop control, the unit's control system diagram shown in Figure 2.
     This is a double closed-loop system, the inner ring is the speed loop, the outer ring is the position loop. Using high-precision grating as a position detection element. The positioning accuracy depends on the resolution of the grating, and the mechanical error of the system can be eliminated by feedback and obtain high accuracy.

      2 Open linear system with linear motor
      Using PC and open programmable motion controller to form a numerical control system to general computer and Windows operating system as a platform, with the standard plug-in form of PC motion controller for the control of the core, to achieve the NC system open. The overall design of the open CNC system based on linear motors is shown in Fig.
      The system uses the PC-card expansion slot to insert the PCI-8132 motion control card program, by the PC, motion control card, servo drive, linear motor, CNC table and other components. Among them, the numerical control table by the linear motor drive, servo control and machine logic control by the motion controller to complete, the motion controller programmable to exercise subroutine way to explain the implementation of numerical control procedures (G code, support for user expansion). The PCI-8132 is a 2-axis motion control card with a PCI interface. It can produce high-frequency pulse-driven stepper motor and servo motor, control the motor movement of the two axes, to achieve straight and circular interpolation. In the NC machining, provide position feedback. Today's industrial control technology in the PCI bus gradually replaced the ISA bus, as the mainstream form of the bus, it has many advantages, such as plug and play (Plug and Play), interrupt sharing, etc., to provide users with great convenience, At present the most advanced PC, the most common kind of bus
      With the rapid development of high-speed processing technology, the transmission and control system requirements are getting higher and higher, so that the linear motor drive technology research efforts gradually increased. Therefore, to increase the research on the linear drive technology is the trend of higher and faster technology development, but also better meet the needs of the market, bring greater economic benefits, become the inevitable trend of future development.
      Kunshan Tongmao Electronics Co., Ltd. is a set of linear motor technology research and development, linear motor, voice coil motor, precision linear platform and marketing as one of the manufacturers. We produce linear motors, linear motors, voice coil motor, voice coil motor has been in the CNC machine tools, CNC and other numerical control system has made a very wide range of applications, need to know more about the linear motor in the numerical control system applications, please contact us www.tmmotion.com, or call: 400-007-7724.