Low Cost Automation Sensor Based Continuous Cut-Off Machine | Automation In Cut-off Machine Project
In the process of production of any components from steel bar stock , the preliminary process is that of cutting-off of bar stock to length according to the finished size requirements of work piece. This process is normally done by an power hacksaw machine.
The sequence of operation is as follows:
1.Feed bar stock to stopper that is set according to length of work piece to be cut.
2. Clamp the bar stock
3. Feed the cutter blade to cut the required length.
4, Retract the cutter
6. De-clamp the work piece
The above sequence if observed has the human intervention through out the process is necessary and more over the process of bar cutting does not add to the value of the product hence can be treated to be an idle time. Thus there is an attempt in the form of continuous cutting off machine to reduce the idle time to a minimal value. In the machine once the bar stock is fed to the stopper the machine automatically feeds the cutter to the work piece until it is cut to the required length during the cutting stroke and during the return stroke the bar will automatically fed to the stopper by the machine itself , and so also the clamping of bar stock during cutting stroke and de-clamping being done by the machine itself.
The solution to the above problem is the development of a low cost automation based machine using a proximity sensor to sense the job feeding ( for semi-auto model feeding the job to length is manual) . ..further clamping , cutter feed , cutter retraction , de-clamp operations are automatic and fast …
The sequence of operation for the machine is as follows:
1. Feed job to length.
2.Proximity sensor senses the job,…..circuit is ‘ON’
3. Clamp cylinder operates to clamp the job
4. Cutter feed cylinder operates to feed cutter in downward direction to cut the job….feed rate is adjusted using flow control valve.
5. Press ‘ PUSH BUTTON’—-Sensor is by-passed …this makes circuit ‘OFF’
6. Clamp cylinder reverses stroke —job is de-clamped
7. Cutter feed cylinder reverses …..return strokes are faster to save idle time.
8. Feed job again …..continue steps 1 to 7
CONSTRUCTIONAL FEATURES :
1. Cutter motor and cutter head : Cutter motor is 100 watt motor variable speed 0 to 8000 rpm ..with a standard 1:3 ratio gear head thus output speed of cutter will be 2600 to 0.
2. Linear slide and cutter feed arrangement: Linear slide comprises of two linear motion bearings on wither side with guide bars and set op helical compression springs. The feeding action is done by a double acting pneumatic cylinder ….speed of the piston in forward direction ie, the cutter feed is controlled flow gradual cutting action using a flow control valve in circuit.,where as the return stroke is standard ( fast action). Springs are provided for fast return of the cutter head to original position.
3. Job clamping and guide arrangement: Job is guided in the job guide where as the clamping is achieved using a set of clamps namely , the set- clamp ( adjustable to accommodate different size of job) ….where as the movable jaw is connected to another pneumatic cylinder which is operated in tandem to the cutter feed cylinder.
4. Job Feeding and sensing arrangement : For the semi-automatic version of the machine the feeding action is manual ie, the job is fed in the job guide manually upto stooper. , the proximity sensor is used to sense the job. The sensor then actuates the electrical circuit comprising of an electronic 8-pin relay and push button system..
5. Proximity sensor and electrical circuit
Proximity sensor and the electronic relay circuit is a simple electrical circuit used to sequence the operations in the circuit , it can also be replaced by an limit switch arrangement….but sensor is more reliable ….the circuit decides the on/off of the 5/2 way direction control valve in the pneumatic circuit and thereby the clamping/cutting /return action.
6. Pneumatic circuit:
Pneumatic circuit uses two double acting pneumatic cylinders , one 5/2 way direction control valve and one flow control valve., functions of the above components have already being explained above.
1. Job feeding upto stopper is sensor based ..so job size accurate.
2. Clamping of bar stock during cutting stroke is automatic
3. De-clamping of bar stock after cutting stroke is automatic
4. Job feeding takes place during return stoke of the machine there by reducing the idle time further.
5. Minimal human intervention only limited to replacing the bar stock on to the machine
1. Job stock cutting in production of automobile and industrial components.
2. Conduit cutting for wire harnesses used in cars
3. PVC sleeve cutting used as insulating material in electrical machine.