The clamping of the work piece by using ordinary mechanical work holding devices uses single work piece for machining in each cycle. So this increase the cycle time hence decreases the productivity. Hence there was a need to design a special work holding devices. According to the specification given by the customer, about the requirement like maximum diameter of the blank, number of teeth to be cut, module, etc. The fixture is designed based on these parameters. The customer use the machine tool for batch production i.e., why the fixture is also designed in such a way that just by changing the upper half part of the fixture, the customer can switch on to other batch production with different specification and apart from this change of speed, feed by changing the gears according the requirement. The problem was to reduce the cycle time by reducing clamping and unclamping time. Since the machining should be vibration free to accurate machining, the problem has been overcome by actuating the mechanism through hydraulic cylinder. Since the machining is carried out for multiple numbers of jobs, it reduces the machining time and hence the overall manufacturing lead-time.
The type of fixtures depends on the component design and type of machine used. Shaft type component require a totally different type of locating and driving arrangement compared to the disc type component with a locating bore. The type of fixture can be grouped into the following categories as:
Locating mandrel and face clamping for disc types of gear blanks with controlled bore for location.
Collet type of shaft type components having a controlled diameter for location.
Fixture with carrier drive for shaft type components located between center