What Is A Fixture?
In a broad sense, any device used to quickly, easily and safely mount a workpiece in any process can be called a fixture.
For example, welding jig, inspection jig, assembly jig, machine tool jig, etc.. Among them, machine tool jigs are the most common, often referred to as jigs .
When processing the workpiece on the machine, in order to make the surface of the workpiece to achieve the size of the drawing, geometry and mutual position accuracy with other surfaces and other technical requirements, the workpiece must be installed before processing (positioning), clamped firmly (clamping). Fixture usually consists of positioning elements (to determine the correct position of the workpiece in the fixture), clamping devices, tool guidance components (to determine the relative position of the tool and the workpiece or guide the direction of the tool), indexing devices (so that the workpiece in a single installation can complete several stations of processing, rotary indexing devices and linear moving indexing device two types), connecting components and clamping specific (fixture base) and other components.
Types of fixtures can be divided according to the characteristics of use.
The types of fixtures vary depending on the processing characteristics of the workpiece. Taking the existing fixtures in the industry as an example, multiple workpieces are clamped at the same time within the processing range of the machine, and the clamping and fixing of different types of workpieces are designed on the same set of fixtures, so that when changing lines in production operations, it is only necessary to replace some parts, such as: pressure plates, positioning pins, reference blocks, hydraulic cylinders and other small parts, in order to achieve the flexible function of quick line change.
①Universal universal fixture. Such as machine vise, chuck, chuck, indexing head and rotary table, etc.
②Specialized fixture. Specially designed and manufactured for the clamping needs of certain product parts in a certain process, the service object is specific and highly targeted, generally designed by the product manufacturer.
③Adjustable fixture. Can replace or adjust the components of the special fixture.
④ Combination fixture. It is a fixture composed of standardized components of different shapes, specifications and uses, which is suitable for single-piece, small batch production and temporary tasks of new product trial production and frequent product replacement.