Input of PLC on woodworking band saw machine

In woodworking machinery, woodworking machine tools such as woodworking band saws, woodworking circular saws, and woodworking frame saws are used to saw logs or timber. The woodworking band saw machine is an endless band saw blade tensioned on two saw wheels. The endless band saw blade is driven by a motor through the saw wheel for continuous cutting motion. According to the classification of use, band saw machines can be divided into sports car band saws for sawing logs and in-segment band saws for splitting boards or squares.
In the sports car band saw machine, the power equipment of the sports car is an electric motor assembled on the chassis, which drives the main shaft of the sports car to reciprocate through gear transmission. The sports car moves forward for the working stroke, and the sports car moves backward for the return stroke. The forward and reverse rotation of the motor controls the forward and backward movement of the sports car table.
In woodworking band saw machine machinery, PLC or single chip microcomputer is usually used to control the operation of the feeding part. The high anti-interference and universality of PLC make up for the shortcomings of the microcontroller control system and make it widely used.
In order to ensure the control precision of the system, the control system of sports car band saw machine adopts closed loop control. Calculate the actual distance of the sports car table based on the pulse signals returned from the rotary encoder. When the sports car table reaches the set distance, the PLC outputs a brake signal to stop the sports car and realize the positioning of the sports car. The PLC control system has a total of 8 switch inputs, including a high-speed pulse signal, a proximity switch signal, and start, stop, enter, exit, and jog. The two switching outputs are brake contactors and back relays, which control the stopping and moving direction of the sports car respectively.
According to the input and output requirements, we choose Hollyas-LEC G3 small integrated PLC with independent intellectual property rights. Considering that this system requires a certain amount of spare I / O points, the CPU module chooses the LM3107 with its own 14-point switch input and 10-point switch output. This module comes with 3 independent tell pulse inputs, and the relay output current capacity is up to 2A. It can directly control the brake contactor without intermediate relay.
According to the requirements of the running process of the sports car table, the PLC compares the pulse value currently sent with the setting value of the touch screen. If the current value is less than the set value, the system outputs the brake signal immediately, and then waits for the input of the next forward signal. When the system needs saw path compensation, the program will perform saw path compensation according to the compensation amount selected by the user.
The woodworking band saw machine with PLC as the control core uses the high-speed counting function of PLC to realize the positioning control of the sports car table. The PLC control system has strong anti-interference ability, which improves the processing accuracy of woodworking band saw machines. The PLC-based control system can be used not only in woodworking band saws, but also in furniture, doors and windows, and wood mold manufacturing industries.