20-05-2013, 04:44 PM
GEAR CUTTING ATTACHMENT FOR LATHE
GEAR CUTTING.docx (Size: 19.26 KB / Downloads: 64)
INTRODUCTION
A new and improved gear cutting machine attachment which facilitates the use of said gear cutting machine as a lathe, said attachment including:
-mounting means for facilitating an attachment to said gear cutting machine;
-lathe means attached to said mounting means; and power supply means for driving said lathe means;
wherein said mounting means comprises a rectangular shaped support member having first and second opposed ends and first and second opposed sides, said support member further having a longitudinal axis and a transverse axis perpendicular to said longitudinal axis, said support member having a dovetailed shaped recess extending parallel to said transverse axis on one of said sides thereof, said support member dovetailed shaped recess adapted to be affixed to the vertically extending dovetail of said gear cutting machine with said other opposed side thereof facing outwardly with respect to said gear cutting machine vertical dovetail.
Conventional lathe and its working
Working principle
Lathe removes undesired material from a rotating workpiece in the form of chips with the help of a tool which is traversed across the job and can be fed into the job. The tool material should be harder than the workpiece and the latter held securely and rigidly in the machine.
The tool ma be given linear motion in any direction. A lathe is used principally to produce cylindrical surfaces and plane surfaces at right angles to the axis of rotation.
A lathe basically consists of a bed (To provide support) , a head stock, a cross slide(to traverse the tool) and a tool post mounted on the cross slide. The spindle is driven by a
Motor through a gear box to obtain a range of speeds. The carriage moves over the bed guide ways parallel to the workpiece and the cross slide provides the traverse motion.
A feed rod and lead screw are provided to power the carriage for cutting the threads.
Limitations
Lathe is suitable for operations like turning,boring,facing,taperturning,thread cutting,knurling,etc., but not suitable for operations like key way cutting,etc., because in a conventional lathe as soon as the machine is switched on,the workpiece fixed to the chuck rotates. This is a major limitation of the conventional lathe keeping inview of the present project work .
Note: although it is not completely impossible to cut a keyway on a conventional lathe it stands no where against the method which the projects deals with.
On a conventional lathe the key way is cut by fixing the workpiece in the tool post and the end mill cutter in the chuck. The major problems that arises due to this are:
The dia of workpiece is limited
The axis of yhe tool and the axis of the workpiece may not coinside.
Hence this method is less efficient in every sense than the method proposed.