controlled semiautomatic printing operationoperation

8/3/2019 CONTROLLED SEMIAUTOMATIC PRINTING OPERATIONOPERATION

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INSTITUTE OF ROAD AND TRANSPORT TECHNOLOGY,

ERODE.

DESDES

IGN OFIGN OFPCPC

CONTROLLED SEMIAUTOMATIC PRINTINGCONTROLLED SEMIAUTOMATIC PRINTING

OPERATIONOPERATION

Presented byPresented byM.DINESH BABU & K.SATHEESHWARANM.DINESH BABU & K.SATHEESHWARAN

THIRD YEAR

((B.E.MECHANICAL ENGINEERINGB.E.MECHANICAL ENGINEERING))

E-mailE-mail:[email protected]:[email protected]

Contact no:Contact no: 95002902989500290298,, 9566988285.9566988285.

CONTACT ADDRESS:CONTACT ADDRESS:

THE PROFESSOR AND HEAD,

DEPARTMENT OF MECHANICAL,

INSTITUTE OF ROAD AND TRANSPORT TECHNOLOGY,

ERODE - 638316

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ABSTRACT

Manual methods are still frequently used to print (textile-fabrics) work

pieces using the conventional printing method. But in conventional method there are

many disadvantages like time consumption, cost etc. Our main aim is to reduce the

time, and hence the cost of the printing operation. Automation therefore always brings

a considerable rationalization effect, produces a more even printed result and reduces

cost. We have obtained the sequence for the printing operation and we have

constructed a pneumatic circuit by using KV map method for the obtained

sequence. We have simulated the circuit by using AUTOMATION STUDIO software

and verified the sequence. Then we constructed a PLC circuit using DIRECT SOFT

software which is used to automate the printing operation. This PLC circuit has been

incorporated in to the PLC device and we automated the sequence in our FESTO

LAB. After that the cylinders are sized based on the force requirement. This is done

with the help of FESTO manual. Further a Pro/E model is created for machine setup

and cost estimation is done for each component which is involved in this process.

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1. INTRODUCTION:

Pneumatics is a portion of fluid power in which compressed air or other gas is

used to transmit and control power to actuating mechanisms. A pneumatic system

comprises of a compressor plant, pipelines, control valves, drive-members and related

auxiliary appliances. The air is compressed in an air compressor and from the

compressor plant the flow medium is transmitted to the pneumatic cylinder through a

well-laid pipe line system. To maintain optimum efficiency of pneumatic system, it is

of vital importance that the pressure drop between generation and consumption of

compressed air is kept very low.

2. EXISTING PROCESS:

In the existing method most of the processes are carried out manually. Some

of the processes are feeding, transformation of ink from stencil to the work piece,

dispatching, i.e., removing the work piece.

2.1 Problem Identification:

Time consumption because of manual work.

High cost.

Fatigue of the workers involved in this process.

In order to obtain a good quality printing the ink must be transferred from

the stencil to the work piece as quickly as possible. But this cant be

obtained manually.

3. SOLUTION:

Thus in order to obtain a good quality printing, the ink must be transferred

from the stencil to the work piece as quickly as possible. This is done with the help of

automation. Here the work piece which is to be printed moves between the gripper

jaws, which then close. The work piece is lifted off the transfer system, turned and set

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down again on the carrier pin which is perpendicular to the plunger descends down

and printing operation is done. All the above mentioned operations are controlled by

pneumatics.

4. REASON FOR CHOOSING PNEUMATICS:

The force range required lies within 1000N to 1200N.

Quick reaction when compared to other systems.

Air source is readily available.

Cost effective.

5. OBTAINING SEQUENCE:

The sequence of operations of the cylinders A, B, C, D is as follows,

Cylinder A: This cylinder is used for vertical movement of the plunger.

Cylinder B: This cylinder is used for horizontal movement of the plunger.

Cylinder C: The gripper jaws which are used to hold the work piece during

Swivel mechanism, are controlled by this cylinder.

Cylinder D: This cylinder is used for performing swivel operation.

Hence the sequence obtained is as follows:

A1A0B1A1A0B0C1D1C0D0

6. ELECTRO PNEUMATICS:

By using electro pneumatics we are able to control the air flow

electrically and hence we can obtain the air actuation more accurately and also the

space occupied is less comparatively because it replaces many mechanical

components. We have constructed the circuit using KV map method. The traverse

step diagram for the sequence is shown below. From this we obtained the

unminimized equations.

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7. TRAVERSE STEP DIAGRAM:

A1 A0 B1 A1 A0 B0 C1 D1 C0 D0

D

C

B

A

8. UNMINIMIZED EQUATIONS:

A1 = a0 b0 c0 d0 A0 = a1 b0 c0 d0 B1 = a0 b0 c0 d0

A1 = a0 b1 c0 d0 A0 = a1 b1 c0 d0 B0 = a0 b1 c0 d0

C1 = a0 b0 c0 d0 D1 = a0 b0 c1 d0 C0 = a0 b0 c1 d1

D0 = a0 b0 c0 d1

. The modified flow diagram is shown. From the modified flow diagram we

calculated the minimized equations. These minimized equations will be used in

constructing the circuit diagram.

9. MODIFIED SIGNAL FLOW DIAGRAM:

X X

Y Y Y Y

d0

c0

b0

a0 A1 B1 C1 X0

a1 Y1 A0

b1

a1 X1 A0

a0 A1 B0

c1

b1

a0

a1

b0

a1

a0 D1

d1

c1

b0

a0 D0

a1

b1

a1

a0

c0

b1

a0

a1

b0

a1

a0 Y0 C0

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10. MINIMISED EQUATION:

__ __ __

A1 = Y X + a0b1 X D1 = Y

__

A0 = Y b0 + b1 X D0 = Y

__B1 = Y X a0 b0 Y1 = a1

B0 = X a0 b0 Y0 = d1

C1 = Y X b0 X1 = a1 b1

__ __

C0 = Y X0 = Y d0

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11. AUTOMATION STUDIO:

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Fig 1. Circuit diagram in AUTOMATION STUDIO

12. ELECTRO PNEUMATICS DIAGRAM:

8

24V0V

STARTY X

A0 B1 X

A1

Y B0

X

A0

Y X A0 B1

X A0 B0

Y C0

D1

Y B0X C1

Y C1

Y C0 D0

XA1 B1

X

A1

Y

Y

D0

D1

Y

A 1 A 0

A 0

A 0

A 1

A 1

A 0 A 1

B 1 B 0

B 0

B 0

B 1

B 1

B 0 B 1

C 1 C 0

C 0

C 0

C 1

C 1

C 0 C 1

D 1 D 0

D 0

D 0

D 1

D 1

D 0 D 1


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Fig 2. Electro pneumatics circuit diagram

13. PROGRAMMABLE LOGIC CONTROLLER:

A PLC is a user-friendly, microprocessor-based specialized computer that carries out

control functions of many types and levels of complexity. Its purpose is to monitor crucial

process parameters and adjust process operations accordingly. The PLC will operate any

system that has output devices that go on and off (known as discrete, or digital, outputs). It

can also operate any system with variable (analog) outputs. The PLC can be operated on the

input side by on-off devices (discrete or digital) or by variable (analog) input devices.

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The PLC circuit is constructed and verified in Direct SOFT software. This is

shown in fig.3. Then an experimental setup which was constructed in FESTO lab is shown in

fig 4. Then a model setup drawn using Pro/E is shown in fig 5.

Fig 3. PLC diagram in Direct SOFT software

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14. EXPERIMENTAL SETUP:

Fig 4. Experimental setup

15. MODEL SETUP:

Fig.5 Model setup (Designed using Pro/E software)

16. SIZING:

Cylinder A

Cylinder BCylinder D

Cylinder C


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Sizing is a process in which the size of the cylinder is calculated and it is

compared with the standard values so that the required size of the cylinder is obtained.

Size of the cylinder A is obtained as follows,

Force = pressure x Area

Force = P x A - R

= P x 10 x 3.14 x d2 - R

4

1000 = 6 x 10 x 3.14 x d2 - 100

4

d = 48.3 mm

Standard value = 50mm (from festo manual)

Similarly sizes of the cylinders B,C,D are calculated using FESTO manual.

Diameter of cylinder B = 40.9 mm (obtained in calculation)


Diameter of cylinder C = 24.16mm (Obtained in calculation)


Diameter of cylinder D= 4.3mm (obtained in calculation)

Standard value = 5.35mm(from festo manual)

16.1 Stroke Length of Cylinders Used:

Stroke length is obtained from the festo manual with respect to the size of the

cylinder and cylinders are specified based on these values.

Stroke length of the cylinder A: 200 mm

Stroke length of the cylinder B: 500 mm

Stroke length of the cylinder C: 40 mm

Swivel angle of the cylinder D: 1800


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17. COST CALCULATION:

The cost was calculated using FESTO manual and listed below:

Cylinders : Rs. 13,250

5/2 Double acting solenoid valves : Rs.3, 330

Air filter regulator unit : Rs.2, 365

PLC : Rs 12,000

Others(tubes, limit switches, lubricator): Rs. 4,260

Total amount : Rs.35, 205

18. CONCLUSION:

The problems pertaining with manual printing operation are identified.

The cost of operation and the time taken is very high in case of manual printing

operation. A semi-automated printing machine operation sequence has been designed

using KV-map method. The results obtained are verified with the results of

simulations performed in AUTOMATION STUDIO. A PLC circuit is constructed and

is verified in DIRECT SOFT. Detailed cost estimation has been carried out. It is

found that the time has been reduced significantly and the cost is also low in long run.

19. REFERENCES:

[1] Antony Barber, (1997), Pneumatic Handbook 8 th edition, Elsevier Advanced

Technology, Oxford, UK.

[2] FESTO Manual

[3] Croser. P, (1989), Pneumatics-Basic level FESTO Didactic KG, D-7300,

Esslingen.


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controlled semiautomatic printing operationoperation

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