1-Our company's safety inspection light curtain has designed the software and hardware system of infrared measuring light curtain according to the requirements of dimension detection in the automobile tire production line. -The system hardware includes infrared emission line array, receiving line array and single-chip microcomputer control system placed opposite to each other, respectively carrying out infrared emission and carrier wave, receiving and filtering and scanning, logic control and data communication with the host computer. Data processing is performed by the host computer, the relative size detection of the measurement object is completed, and the real-time imaging of its contour is performed. After system debugging and optimization, the resolution of our safety light curtain measurement light curtain is 4mm, and the scanning speed when the detection width is 2032mm can reach 10 lines per second, which fully meets the application requirements. This kind of light curtain is also called tire Dimensional measuring light curtains.

2-Infrared scanning logic uses a 38kHz frequency carrier to exclude external visible light interference. At the same time, the double-cross synchronous scanning method is adopted to improve the resolution of the detection light curtain. Due to infrared scattering and diffraction, the measurement error of the detection light curtain will increase, and the imaging edge will be uneven. For this reason, a light-shielding baffle is designed to focus the infrared rays, which effectively reduces the emission angle of the infrared emitting tube and the incidence of the receiving tube. Angle, improve the measurement accuracy of the detection light curtain.

3. As a sensor to detect the light curtain, it can complete the measurement work with the host computer through the serial interface, and the communication protocol is designed for this purpose. Also the communication protocol adopts HEX.ASCII code data format, each frame of data consists of identification code, data code, check code, and supports a baud rate of 9600--19200 bits. --The communication software of the single-chip microcomputer is written in assembly language, and the communication interface and software of the single-chip microcomputer control system of the measuring light curtain and the upper computer are developed based on the Visual Basic language, and the software for communication, measurement and object contour imaging of the PC, debugging indication, and the upper computer can meet the parameters. Settings, data processing and live imaging functions.

4. The safety light curtain microcontroller control system takes AT89C52 as the core, expands the RS-485 and RS-232 interfaces respectively for serial communication with the PC, cleverly uses the timer of AT89C52 to design the scanning and control sequence, completes the carrier, shifts At the same time of bit and positioning signal, data exchange with PC, infrared emission and reception circuit, the scanning method of shift register series gating is adopted, which minimizes the connection between the single-chip microcomputer control board and the infrared emission board and the receiving board. Number of lines, improve system stability and anti-interference ability by reducing long-line effect, the PCB of infrared emission-receiving line array is designed as a cascade structure, that is, it is composed of the same 1 to 8 PCBs with a length of 254mm in series, according to user parameters. Software selection to meet the measurement requirements of 254mm--2032mm range.