DESIGN AND FABRICATION OF PAPER PUNCHING MACHINE

DESIGN AND FABRICATION OF PAPER PUNCHING MACHINE

ABSTRACT

Paper punching is one of the important process in spiral binding industry. The project selected is based on automation and this help to improve spiral binding works. The project titled “DESIGN AND FABRICATION OF PAPER PUNCHING MACHINE”.

The motor is used for operating the punching head. Hence human fatigue is reduced. So it can find application in all spiral binding shops.

INTRODUCTION:

An eccentric cam mechanism is used for punching papers for spiral binding . It can be used in all spiral binding shops.

To operate the punching head an electric motor is needed.If the motor is ON, the cam attached to the motor with speed reduction mechanism will rotates. As it rotates the pull rod will oscillates up and down.

This reciprocating motion is transmitted to punching head and it punch the papers when the punching head moves in downward direction.

This machine reduces human fatigue and reduces punching time than manually operated machine. Due to this number of sets of paper can be punched in a very short time. So this machine finds application in all spiral binding shops.

MAIN COMPONENTS AND ITS DESCRIPTION:

The major parts used in our project are

v Frame

v Electric motor

v Reduction gear box

v Eccentric cam mechanism

v Punching head

v Punching head mechanism.

FRAME:

It is the basic skeleton structure withstands all components such as electric motor, gear box, pull rod and punching head and loads acting while punching paper.

ELECTRIC MOTOR:

It is mounted at bottom of the frame and its shaft is mounted by a pulley and a “V” belt drive which drives the gear box. It converts electrical energy into mechanical energy. A 1HP motor, single phase, with 1440 rpm is used for our project.

REDUCTION GEAR BOX:

It is also mounted on the bottom of the frame. It has pulley at one end to which motor drive is connected and another end (output shaft) is connected to eccentric cam mechanism. It uses a speed reduction gear box with ratio of 40:1. Worm and worm wheel is used for speed reduction

ECCENTRIC CAM MECHANISM:

In this mechanism a flat plate is mounted to the gear box output shaft. An another pin is fixed with an eccentric distance in the flat plate to perform cam function. In the pin a bearing is mounted over which a bush is mounted. The pull rod is attached to the bush. And the whole eccentric plate mechanism is bolted to the gear box shaft.

RAM HEAD:

It is a flat plate to which pull rod is attached, and it slides with respect to sliding mechanism as eccentric cam rotates. In sliding mechanism a bush slides over a circular rod, which is mounted on the frame. The punching die is attached to the bottom side of the flat plate. The follower of punching die is attached to the frame in which punching pins reciprocate.

CONSTRUCTION:

This machine has a rigid frame made with L angles and it is welded rigidly. The electric motor is connected to reduction gear box through “V” belt, here first reduction of speed takes place. The reduction gear box has a warm and warm wheel in which second speed reduction takes place.

In reduction gear box a worm and worm wheel is used for speed reduction. At the output of reduction gear box an eccentric cam plate is used to obtain reciprocating mechanism.

A follower (pull rod) which connects both eccentric cam and punching head. The punching head is guided in a bushed shaft. The shaft is clamped to frame by U clamp on both sides. The bottom side of punching head has punching pins which actually make holes on papers. The bottom side of the punching pins will slide in a guide plate which helps in good quality of punching.

WORKING PRINCIPLE:

If the electric switch is ON the motor will rotates, as it rotates it drives the gear box shaft. As the diameter of gear box pulley is larger than the motor pulley speed reduction takes place. In gear box worm and worm wheel is used high speed reduction takes place in the order of 40:1 ratio.

Then the output of gear box is connected to eccentric cam plate. Due to speed reduction the will rotates at very slow speed. As the eccentric cam has a follower over it makes the pull rod to reciprocates. The movement of punching head depends upon the eccentricity of cam. The punching head has a siliding mechanism in which the punching head is guided up and down. The bottom of the punching head has a hole plate to guide the pins accurately without bending. After switch ON the motor the paper is placed between the head and base. The punching action takes place when the punching head moves down wards. This process is repeated for as number of times for punching number of sets of papers.

DESIGN CALCULATION:

SPEED REDUCTION CALCULATION:

First speed reduction:

RPM of MOTOR- 1440

Pulley dia. in motor- 4inch

Pulley dia. in gear box- 7inch

Input RPM of GEAR BOX = (1440*4) / 7

= 822.875

=823rpm.

Second speed reduction:

Input RPM of gear box= 823 rpm.

Gear box ratio= 40:1

Output of gear box= 823/40

=20.57

= 21rpm.

Eccentricity of cam:

Offset distance in cam plate= 20mm

Distance moved by punching head= 40mm.

Diameter of pins = 4mm dia.

Length of die = 300mm.

Size of paper can punch = A4.

LAYOUT OF MACHINE:

1- FRAME

2- ELECTRIC MOTOR

3- PUNCHING HEAD

4- PULL ROD

5- REDUCTION GEAR BOX

APPLICATION:

It can be used in all spiral binding shops and paper punching industries.

MERITS:

Less time consumption.

More number of papers can be punched easily.

Human fatigue is reduced.

Less operational cost.

DEMERITS:

Cannot be operated without power supply.

CONCLUSION:

In designing and fabricating this project, we gained invaluable technical knowledge, regarding material solution, planning the project, group efforts in achieving the target, cost estimation and also gained confidence in doing works.

How ever, in completing the project we felt that aims of the implementation of project work in our courage is completely fulfilled.