-: Indexing :-
The method of dividing the periphery of a job into equal number of divisions is called indexing .
-: Types of Indexing :-
There are mainly four types of indexing methods -
1- Direct Indexing
2- Simple / Plane Indexing
3- Compound Indexing
4- Differential Indexing
5- Angular Indexing
1- Direct Indexing :-
The simplest method of indexing in which index crank movement is directly transmitted to the work without using a worm and worm wheel in between is known as Direct Indexing .
This method is employed only on work that requires a small number of divisions . In this method , the index plate is attached to the spindle and rotated by hand . The workpiece can be rotated by rotating the index plate . The index plate usually has 24 equally spaced holes that make it possible to index directly any number of divisions which is a factor of 24 .
2- Simple / Plain Indexing :-
In this method , the dividing head spindle is moved by turning the index crank . The shaft carrying the index crank has single threaded worm which meshes with the worm gear having 40 teeth. Thus , 40 turns of crank are necessary to rotate the spindle through one revolution .
This method of indexing is used where it is required to divide a periphery into more number of parts than is possible by rapid indexing .
3- Compound Indexing :-
This method is employed when the number of divisions required on the work is outside the range of holes provided on the index plate secured by simple indexing . Normally , the index plate is locked to the body of the dividing head by means of a plunger fixed to the body and radially adjustable to get in any of the plate holes from the back .
4- Differential Indexing :-
Differential indexing is a very useful method of indexing by which almost any number of divisions can be obtained . This method is used when the required number of divisions can not be indexed by simple indexing for want of a circle on the index plate with the correct number of holes .
5- Angular Indexing :-
It is desirable to carry out indexing using the actual angles rather than equal number along the periphery, then angular indexing would be useful . Since the 40 revolutions of the crank equal to a full rotation of the workpiece , which means 360º , than one revolutions of the crank is equivalent to 9º .
The method of dividing the periphery of a job into equal number of divisions is called indexing .
 |
| image source: google |
-: Types of Indexing :-
There are mainly four types of indexing methods -
1- Direct Indexing
2- Simple / Plane Indexing
3- Compound Indexing
4- Differential Indexing
5- Angular Indexing
1- Direct Indexing :-
The simplest method of indexing in which index crank movement is directly transmitted to the work without using a worm and worm wheel in between is known as Direct Indexing .
This method is employed only on work that requires a small number of divisions . In this method , the index plate is attached to the spindle and rotated by hand . The workpiece can be rotated by rotating the index plate . The index plate usually has 24 equally spaced holes that make it possible to index directly any number of divisions which is a factor of 24 .
2- Simple / Plain Indexing :-
In this method , the dividing head spindle is moved by turning the index crank . The shaft carrying the index crank has single threaded worm which meshes with the worm gear having 40 teeth. Thus , 40 turns of crank are necessary to rotate the spindle through one revolution .
This method of indexing is used where it is required to divide a periphery into more number of parts than is possible by rapid indexing .
3- Compound Indexing :-
This method is employed when the number of divisions required on the work is outside the range of holes provided on the index plate secured by simple indexing . Normally , the index plate is locked to the body of the dividing head by means of a plunger fixed to the body and radially adjustable to get in any of the plate holes from the back .
4- Differential Indexing :-
Differential indexing is a very useful method of indexing by which almost any number of divisions can be obtained . This method is used when the required number of divisions can not be indexed by simple indexing for want of a circle on the index plate with the correct number of holes .
5- Angular Indexing :-
It is desirable to carry out indexing using the actual angles rather than equal number along the periphery, then angular indexing would be useful . Since the 40 revolutions of the crank equal to a full rotation of the workpiece , which means 360º , than one revolutions of the crank is equivalent to 9º .
No comments:
Post a Comment