With the advancement of China's production technology, in the machinery manufacturing industry, CNC machine tools are more and more popular among enterprises. On the one hand, the company invests a large amount of money to purchase CNC machine tools, on the other hand, it renews and transforms existing ordinary machine tools, and adds CNC to ordinary machine tools. The installation of ordinary machine tools into CNC machine tools is an important technical improvement measure faced by many small and medium-sized enterprises. 2 Machine tool overall design CNC transformation The ordinary machine tool mainly solves the relationship between the machine tool and the transmission part of the moving part. The movement of the CQ6123 ordinary lathe mainly includes: (2) Feeding motion transmission chain one by one, vertical and horizontal Feeding; due to the consideration of the CNC lathe-oriented teaching practice, the transformation process is subject to the financial conditions, the overall design is as follows: cancel the thread processing drive chain, the modified lathe can not process the thread; the longitudinal feed and the lateral advance The transmission chain is controlled by ring, the ball screw drive is used vertically, the common thread drive is used horizontally; the tool holder is controlled by microcomputer and can be automatically indexed; -1 type CNC system; main technical parameters: longitudinal feed pulse equivalent 0 01mm/step , fast forward speed 1.1mm / min; lateral feed pulse equivalent 0.005mm / step, fast forward speed machine tool overall design, as shown in 圄 1. 3 Mechanical part transformation 3.1 The longitudinal feed system adopts the stepping motor to drive the ball screw pair through the reduction gear pair, and the screw nut is fixed on the slide box to drive the slide to move left and right. From the appearance of the machine, the stepper motor is mounted on the left end of the longitudinal feed screw and the handwheel is mounted on the right end for manual control. 3.2 Lateral feed system The stepper motor drives the screw nut through a pair of reduction gears to push the knife carriage to make lateral movement. Because the diameter of the small desktop lathe screw is too small, the finished screw can not be purchased, and the design customization price is high. Therefore, the transmission performance of the ordinary triangular thread nut is poor, but it can be compared with the ball screw transmission scheme used in the longitudinal direction for comparison. Considering the appearance of the machine tool and the adjustment of the cutting tool, the original structure of the carriage is unchanged, and manual operation can still be performed, and the stepping motor is installed below the rear end of the carriage. 3.3 The tool holder is replaced by a four-station electric self-rotating tool holder. The stepping motor is used for automatic indexing, and four turning tools can be clamped at the same time. The electric tool holder cooperates with the CNC system to call any turning tool in the main program. 4 characteristics of the numerical control system This system is designed and manufactured by the syCNC-1 type numerical control system, which adopts modular design. The whole system consists of three relatively independent subsystems, namely: CPU board, I/O board keyboard/display board, which is based on the stacking mode of PCA04 bus to improve the reliability of the connection. The system design is tightly focused on the guiding ideology of improving reliability, convenient use and cost reduction. The main features are: 2 with a backlit character dot matrix liquid crystal display template as a display interface, abandoning the traditional digital tube display, flexible display, and its own controller Can reduce the burden on the CPU. (2) Menu driven. Full menu drive, friendly man-machine interface, intuitive operation, concise and fault-tolerant. -1 Borrowing the basic idea design of the full-screen editing software QEDIT in the PC or the editing module similar to the host in operation and function, the system editing and processing program is flexible, convenient and not easy to make mistakes. (4) High reliability. Both aspects of software and hardware have adopted industrial anti-jamming measures, so they have high reliability. Design of 5syCNC-1 CNC System 5.1 Hardware Design 511 Overall Structure In order to facilitate future system expansion and improve system maintainability, the syCNC-1 CNC system adopts modular design. The entire system consists of three separate subsystems: CPU board, I/O board, keyboard/display board. The connection between the three boards draws on the stacking method of the PC/104 bus to improve the reliability of the connection. The system uses Intel8031 microcontroller as the core, and expands the system process of 32KB. Among them: 2K bytes of user program storage space has power-down protection. In addition, through the 8255 programmable I / O chip, the four-station electric tool post interface has been extended, the menu drive is used, and the soft keys are widely used. Therefore, the keyboard system of the syCNC-1 numerical control system has a total of 30 keys. In doing so, on one hand, the complexity of the hardware can be reduced, and on the other hand, the difficulty of the operation can be reduced. 512 anti-interference measures In order to ensure the safe and reliable operation of the system, effective anti-interference measures must be taken. In addition to the rational design of the line, syCNC-1 adopts the following measures to improve reliability: (3) Strengthen the driving ability of the bus. The bus driver circuit is used to drive the bus capacity to avoid malfunction of the CPU due to load fluctuations. (4) All input/output signals are isolated by opto-electronic coupling to prevent external interference signals from entering the CPU board. 5.2 software design 521syCNC-1 system software syCNC-1 system software design flow, as shown in 圄 3. Cold start cold start white check, N report anchor error number 1 self test pass, system initialization ~.1. Display main menu read ti I manual Iaa. Beijing: Mechanical Industry Press, 1994. Yu Yingliang. Machine tool NC transformation design and examples. Beijing: Mechanical Industry Press, 1998. (Finish) Low Temperature Refrigeration Unit,Low Temperature Screw Chiller,Low Temperature Screw Freezer,Small Low-Temperature Refrigeration Unit DONGGUAN CARNO MACHINERY CO., LTD. , https://www.kainuochiller.com