[Abstract] The crystal oscillator cutting machine industry in Taizhou, Zhejiang Province, has developed rapidly. As this equipment is a specialized machine with a fixed market capacity, manufacturers have invested heavily in improving processing equipment and automation to seize market share and maximize profits, thereby enhancing processing efficiency and product quality. Fully automatic crystal oscillator cutting machines have thus emerged as a necessary piece of equipment for cutting and processing. This article introduces the application of Delta Electromechanical products in crystal oscillator cutting machines.
[Keywords] Servo; Inverter; PLC; Human-Machine Interface
1. Composition of the control system
Delta servo systems: two ASD-A2023MA units, one ASD-B0123MA unit, and one ASD-B04123MA unit;
Delta frequency inverter: VFD00212LA;
Delta PLCs: two DVP28SV units and one DVP16SP unit;
Delta HMI: One DOP-A57THTD;
Delta power supply: One DTC1000.
2. Working principle and control requirements
(1) The DVP28SV has 4 high-speed pulse outputs (200kHz), two-axis interpolation commands, and 16k Steps of program memory. It can be connected to the full range of SA/SX/SC/SS/SV expansion units, including digital input/output (maximum input/output expansion points up to 512 points), analog modules (A/D, D/A conversion and temperature control unit) and new high-speed expansion units, etc. It can meet various application occasions, and is small in size and easy to install.
(2) High-speed control is achieved by utilizing the Delta ASD-A2023MA servo with a settling time of less than 1ms, a speed bandwidth of 450Hz, good low-speed operation characteristics, and an actual error of only 0.5% for a full circle under a speed command of 1rpm. The high-speed DSP performance with an acceleration time of 10ms from -3000rpm to 3000rpm under no-load conditions.
(3) Two ASD-A2023MA servos are used to control the wire feeding and take-up of the cutting machine respectively. One ASD-B0123MA servo controls the back-and-forth swing of the wire during take-up, and the other ASD-B0123MA controls the vertical lifting of the machine table feeder. The speed of the wire feeding and take-up rotors of the cutting machine is required to be synchronized to meet the requirements of high-speed cutting. The control requirements are achieved through PLC and servo.
(4) The frequency converter is mainly used to control the running speed of the cable motor and the coolant motor, and to maintain the constant speed and stable operation of the equipment.
3 Hardware Framework Diagram
The wiring diagram of the PLC control point system is shown in Figure 1.
The wiring diagram for the spindle servo control is shown in Figure 2.
The wiring diagram of the wire laying servo control system is shown in Figure 3.
The wiring diagram of the take-up servo control system is shown in Figure 4.
The wiring diagram of the lifting servo control system is shown in Figure 5.
The wiring diagram of the power control system is shown in Figure 6.
4. System Features and Functions
(1) The selection of transistor output modules can improve the response performance of the entire system and ensure the lifespan of machines with frequent operations.
(2) A very user-friendly human-machine interface, easy to operate and learn; when the machine malfunctions, an alarm message pops up;
(3) The entire system is compactly arranged, eliminating many relays and buttons, making it simple and convenient for users to maintain;
(4) The selection of B-series frequency converters ensures that the spindle can operate normally at both high and low speeds.
5. Calculation of main parameters
Servo feed frequency (Hz) = Feed set speed (mm/s) / Screw pitch (mm) * 10000 * Electronic gear ratio
Inverter operating frequency (Hz) = Set speed (rpm) * 5000 (Hz) / 480 (rpm)
6. Main parameters
The main parameter settings are shown in Table 1 and Table 2.
7. Conclusion
After actual testing, the above control scheme has successfully met the requirements of the crystal oscillator cutting machine's control process, achieving high cutting speed and high precision. The entire machine has been accepted by the customer. Compared with control equipment using components from well-known foreign brands, while maintaining the same performance, the processing efficiency is increased by 1/3, and the cost is significantly reduced.
About the author:
Wang Zhirong: Born on September 26, 1979, he graduated from Jiangxi University of Science and Technology with a major in CNC technology. In 2008, he joined Delta Electronics Co., Ltd. as an application engineer, mainly responsible for the technical application of products. He is currently a senior sales engineer at Delta Electronics Co., Ltd., mainly engaged in product marketing and channel management, and has rich experience in technical application and market sales management.
