The design of machine element is the most important step in the complete procedure of machine design. In order to ensure the basic requirement of machine elements, calculation are carried out to find out the dimensions of the machine element. These calculation form an integral part of the designing of machine elements.
The floor space acquired by the machine is too large thus we decided to cut the length of machine up to 6 feet and also height up to 4.5 feet and put the width as it is because it is the size of standard paper. ( But as our project is a demo project we decided to take the width 3 feet. ) Then they have also used the complex mechanism for mounting the roll which is to be re-winded.
So we decide to use the Self aligning bearing with extended inner ring for easy mounting and un-mounting. Then we see there a cutter and roll adjustment for cutting paper Which add extremely high wt. to machine and decided to give some new design which is also discussed .
Then as they are using the motor mounting outside the structure it consumes much more floor space and also create difficulties in operating the break. So we are Giving the motor mounting adjustment within the structure itself. Above and other modifications are explained in sequence with the structure fabricating process in the report.
Roll For Cutter Mounting:
In above way four rolls can be machined. In conventional machine either: (1) Grooved rolls are used which are made up of 6-7 mm thick pipe having diameter of about 100-120 mm. Various equidistance grooves are made on periphery of that roll but it increase the weight tremendously. or (2) A solid bar of 30-40 mm is used on which the aluminium bushes of diameter 60-70 mm and thickness of about 25-50 mm are used.
the cutter is then fixed between any two consecutive bushes for cutting purpose. but it also increase the weight. For weight loss, making operation easy, eliminate excess machining and give freedom of cutting paper of any size we are design a bush having only one groove of 3 mm thickness and 5 mm depth on the periphery of bush. And on either side of bush there are the steps of 5 mm thickness and having diameter equal to inner diameter of core pipe.
The core pipes are used to rewind paper. These are also made up of paper but are much tuff to sustain higher weight. When paper being cut it is preferred that it must not be loosen between grooved bush and end plate so firstly we think of using wooden blocks between end plates and grooved bush.
But there is one problem that if you want to change the size of paper being cut, you have to change the distance between endplates and grooved bush and also size of wooden block accordingly. and it will take much time to machine the block so we decide to use core pipe.
It is simple to use core pipe than any other option. Because one can adjust the bushes and cut the core pipe of required size within few minutes. When using our new adjustment firstly we have to measure size of paper and adjust the end plates, then decide the size of rolls have to be cut and adjust the grooved accordingly. Then measure the distance between grooved bush and each end plate and cut core pipe accordingly.
then fix the one piece of core pipe between one end plate and one side of grooved bush, then fix second piece of core pipe between second end plate and other side of grooved bush. The bush and end plates have nuts to fix them with bar thus they will not move. Then take the roll and with the help of pillow block, bolted it on the column. But one precaution has to be taken that the cutter shaft must be parallel to the roll at bottom on which paper is to be rolled