Fixture is used for cutting the work piece in the process of guide cutting tools and fixed position and supporting work piece clamping device. Fixture is roughly divided into two kinds: Drilling Fixture and Boring Fixture. Among them the Drilling Fixture is most common. Drilling Fixture is for short of Drilling Jig, mainly used for machining hole and screw thread. It is mainly composed of drill set, drill template, positioning and clamping device. The main types are:
(1) Fixed Type Drilling Jig, in use, this kind of Drilling Jig is mainly used for Vertical Drilling Machine machining large diameter single span or Radial Drilling Machine processing parallel hole. Drilling Jig position is fixed on the machine tool, and machining precision is higher.
(2) Sliding Column Type Drilling Jig, is general adjustable fixture with elevating drilling templates. This Drilling Jig has simple structure, convenient operation, action quick and short manufacture cycle advantages, widely used in the production.
(3) Cover Board Type Drilling Jig, this drilling jig no specific folder, its positioning elements and clamping device is directly installed on the drill template. Drill templates in work piece jacket, suitable for big volume, heavy work piece machining of holes. Fixture structure is simple and light, easy to remove scraps; But each fixture should be from the work piece loading and unloading, time consuming, so the weight of the drill fixture should be smaller.
(4) Rotary Type Drilling Jig, this type Drilling Jig can work out several on the work piece around the spindle of the distribution of the spindle or radial hole, because Drilling Jig with dividing device.
(5) Tilting Type Drilling Jig, its structure is simple, Drilling Jig processing generally manually flips, so fixture and work piece are lighter. It can reduce the number of installation, improve the processed hole position accuracy. So is mainly used for machining small work piece of different on the surface of the pores.