The terms “fixture” and “fixture” are often used because they are close in use, so they are often confused or even misused.
Primarily as a tool to assist in controlling position or movement (or both), focusing on work and guidance tools; fixtures focus on holding the tool in a fixed position. Some devices that have both of these functions (control and guidance tools) are also referred to as jigs, but devices that only hold but do not have a guiding tool are referred to as “clamps” rather than “fixtures.”
Definition of fixture: A device used in a mechanical manufacturing process to fix a workpiece so that it occupies the correct position for construction or inspection. Also known as fixtures.
Fixtures and fixtures, because of their close proximity, are often easily confused or even misused. Fixtures focus on work and guidance tools. The jig is a large class of tools for woodworking, ironwork, fitter, mechanics, electronic control, and other handicrafts, primarily as a tool to help control position or action (or both). Because Taiwan was once ruled by Japan for a long time, it was used to the term “fixture.” The fixture focuses on holding the tool in a fixed position. Some devices that have both of these functions (control and guidance tools) are also referred to as jigs, but devices that only hold but do not have a guiding tool are referred to as “clamps” rather than “fixtures.”
Broadly speaking, any device used to quickly, conveniently, and safely mount a workpiece in any process can be referred to as a fixture. For example, welding fixtures, inspection fixtures, assembly fixtures, machine tool fixtures, etc. Among them, machine tool fixtures are the most common, often referred to as fixtures. When machining a workpiece on a machine tool, in order to achieve the technical requirements of the dimensions of the workpiece, the geometric shape and the mutual positional accuracy with other surfaces, the workpiece must be mounted (positioned) and clamped (clamped) before machining. . The fixture usually consists of a positioning element (determining the correct position of the workpiece in the fixture), a clamping device, a tool guiding element (determining the relative position of the tool to the workpiece or guiding the tool direction), and an indexing device (to enable the workpiece to be installed in one installation) Complete the processing of several stations, including rotary indexing device and linear moving indexing device), connecting components and clip specific (clamp base).
The types of fixtures can be divided into:
The type of fixture varies depending on the processing characteristics of the workpiece. Taking the existing fixtures in the industry as an example, multiple workpieces are clamped simultaneously in the processing range of the machining machine, and the clamping and fixing of different types of workpieces are designed. In the same set of fixtures, only some parts can be replaced when the production line is changed, for example, pressure plate, positioning pin, reference block, hydraulic cylinder and other small parts, in order to achieve the elastic function of quick change line.
The fixture is an auxiliary tool that is very convenient and fast during the machining process. Therefore, designing a suitable fixture is an important issue for a small amount of processing.
1 universal universal fixture. Such as machine vise, chuck, suction cup, indexing head and rotary table, etc., have great versatility, can better adapt to the processing process and the transformation of processing objects, its structure has been shaped, size, specifications have been series Most of them have become a standard accessory for machine tools.
2 special fixtures. It is specially designed and manufactured for the clamping needs of a certain product part in a certain process. The service object is specific and highly targeted, and is generally designed by the product manufacturer. Commonly used are lathe fixtures, milling machine fixtures, drill molds (machine tool holders for guiding tools to drill holes or reaming holes on workpieces), die cutters (machine tool holders for guiding the boring bar for boring on workpieces), and pallets (for Mobile fixture on the automatic line of the combined machine tool).
3 adjustable clamps. A special fixture that can be replaced or adjusted for components.
4 combination fixtures. A fixture consisting of standardized components of different shapes, sizes and uses, suitable for single-piece, small batch production and temporary tasks for new product trials and frequent product changes.
Design features of fixture fixtures:
Fixture fixture is an auxiliary tool for machining. Under the requirements of automatic machining, the fixture fixture is designed to use gas and oil pressure as the clamping power. The operator can press the start button to clamp the workpiece and process it. When designing fixture fixtures, special consideration should be given to: clamping force, clamping support point, positioning reference point, ease of chip removal, oil and gas pipeline design, auxiliary support design and blank reference.