Spot Welding Controller

Abstract: Resistance spot welding (RSW) is a process in which contacting metal surfaces are joined by the heat obtained from resistance to electric current. Work pieces are held together under pressure exerted by electrodes. The process uses to shaped copper alloy electrodes to concentrate welding current into a small spot and to simultaneously clamp the sheets together. In industries at the working time some accidents happens due to machine dose not contains any controlling part. Also there a problem of less accuracy occurs in some of the products. That‟s just because of operator cannot find the instant at which electrodes capacity of welding gets over.Also problem occurs in variable distribution of water pressure, air pressure, so the requirement is we have to detect such condition & machine should be stop. So the project contains PIC16F877 Controller which is going to control all such conditions. When the air, water pressure will vary below or above the range the buzzer will on machine power will off. At the input side maximum count of spots we can provide through functional keys.Simultaneously LCD will show the count of weld spots product. When a limit of count will exceed the machine will stop automatically. So the operator can move for maintenance. After that to start the machine there is a reset switch is designed and while working to stop machine there also one emergency switch we are going to add.

Keywords: PIC16F877 Controller; Closed loop system; System lifetime; System maintenance Algorithm.