BRAZING CLIP ASSEMBLY MACHINE USING PLC (SPECIAL PURPOSE MACHINE)-EEE Final year Project

ABSTRACT      

It is special purpose machine by using Allen Bradley plc. This is used to manufacture the clip, which is used in starter of four wheelers. The purpose of the clip is to join the copper winding and commutator In inside the starter.

For this machine we designed electrical panel board by using plc, relay board, smps, mcb, transformer, pneumatic cylinder, solenoid coils, pushbutton etc…

This machine consists of four pneumatic cylinders. They are Top cylinder, Bottom cylinder, Hold cylinder, Feeder cylinder. The bottom cylinder has three proximity sensors i) Top cylinder top sensor, ii) Top cylinder middle sensor, iii) Top cylinder bottom sensor. The bottom cylinder has one proximity sensor as well as hold cylinder and feeder cylinder has each separate proximity sensor. Photo guard is attached in this machine, its for safety purpose when the photo guards detects some interrupts it will stop the machine completely.

This machine can be run in two modes they are auto mode and manual mode. In manual mode the operator can control this machine through the operator panel.

Introduction

As we have known about the importance of time management especially in transportation, we are in need of using two-wheelers or four wheelers enormously. But assembling these vehicles the part of the electro-magnetic power is inevitable. Similarly the assembling of wire is also very important. For this purpose in a familiar company like LUCAS-TVS PVT Ltd. They are using “BRAZING CLIP ASSEMBLY (Special Purpose Machine) as in small designs for erecting the commutator with copper wire. The main function is to clip or hold the commutator and copper winding in commercial starter. The use of brazing clip assembly machine is to save Rs1crore per annum and this machine produce 32products per minute.

But let it be our basic project to know, how this assembly is made. The design of this project is our project is our basic view. So we have decided to design this project with PLC along with K.P ENGINEERS.

ALLEN BRADLEY PLC

OPERATION

This machine can be operated by two manners, they are

i)   Auto mode

ii)  Manual mode

AUTOMODE

              In this mode all pneumatic  cylinders are controlled and operated  by automatic process. When  we switched ON automode , the machine will check top cylinder top sensor switch, bottom cylinder sensor, hold cylinder sensor,  feeder cylinder sensor  and also photo guard are energized. If every sensors are energized, the machine will go to cycle ready. The cycle ready is indication, to show the machine is in ready condition to start. When we get cycle ready signal, We can start machine production by cycle start switch. After switched on cycle start, the top cylinder will move in forward condition, so that time, the top cylinder middle sensor will sensed, and this sensor energize the hold cylinder. The hold cylinder start to move forward, the sensor connected with hold cylinder will energize, it starts the feeder cylinder to move forward, after feeder cylinder sensor energized. The bottom cylinder will move towards forward direction, when it reaches the bottom cylinder sensor and it will start bottom reverse timer,  after finishing of  timer, the bottom cylinder will come back to its rest position. i.e It will move into reverse direction and come back to its original position, similarly when reverse direction of bottom cylinder started, it will start  top cylinder reverse timer, after finishing of delay, forward cylinder also act into reverse direction and it back to its rest position.  This process will continue in automode upto when automode is stopped or some interrupts occur in machine.

MANUAL MODE

In this mode the machine is totally controlled by operator through operator panel. After putting the machine in manual mode, we can push top cylinder push button, so the forward cylinder will move towards forward direction, when the forward cylinder moves forward direction it will start timer, this timer is used as inter locking, after finished of time delay only, the reverse operation of top cylinder will work. Like as , we can push bottom cylinder push button, so the bottom cylinder will move towards forward direction, when the bottom cylinder moves forward direction it will start timer, this timer is used as inter locking, after finished of time delay only, the reverse operation of bottom cylinder will work. When we press hold cylinder push button it moves forward and also reverse direction, feeder also as a same operation when we press feeder cylinder push button it moves forward and also reverse… the above all operation operated through plc program.

CIRCUIT DIAGRAM DESCRIPTION

Block Diagram

The connection diagram of this panel board is explained as per the block diagram. Now we are going to explain about that block diagram connection in detailed view. The main power is connected to power terminal block, the output of the power terminal block is connected to the circuit breaker. The circuit breaker is used as a safety device. The circuit breaker output is connected to the transformer. The transformer we used is a mutual inductance transformer. We used transformer here, to get an constant supply to smps. The smps received power from transformer, and it converts 230ac voltage into regulated 24v dc. The dc supply is again controlled by mcb and its given to all device which are used in this panel. The plc is powered on by smps output. The input to plc, received from operator panel and proximity sensors. All inputs are 24v only, and the inputs are given to plc through input terminal blocks. The output of the plc is afil and the pneumatic cylinder is controlled by solenoid coil.