​Design Specification For Process Assembly Jigs

    As far as the machinery and equipment industry is concerned, the generalized fixtures can include Machine Fixture, Press Fixture, Heat Treatment Fixture, Welding Fixture, Assembling Fixture and so on. In a narrow sense, fixtures generally refer to machine fixtures, which can be referred to simply as fixtures. They are mainly used for machine processing and are also a bridge between the machine and the workpiece and the tool. At present, the more general term is defined as "device tool for clamping workpiece". Fixture. "The device tool used to clamp the workpiece and cooperate with the guiding tool" is called a jig or a jig. Here, we will not focus on this aspect. Please refer to the following web links for specific related design theories; some of the content can also be used as a reference and reference for the design of fixtures in the electronic light industry!

      As far as the electronic light industry is concerned, fixtures can be divided into three types: process assembly fixtures, project testing fixtures and circuit board testing fixtures. Among them, process assembly jigs include assembly jigs, welding jigs, disassembly jigs, dispensing jigs, irradiation jigs, adjustment jigs and shearing jigs; while project test jigs include life test jigs , Packaging testing fixtures, environmental testing fixtures, optical testing fixtures, shielding

Fixtures, sound insulation test fixtures, etc.; circuit board test fixtures mainly include ICT test fixtures, FCT functional fixtures, SMT furnace fixtures, fixtures and CCD test fixtures.

　　 Here, we mainly focus on the process and assembly jigs, the others are only briefly introduced!

      Usually, the main materials of jigs are steel, bakelite, PVC board, acrylic board, epoxy resin board and high temperature resistant synthetic stone.

Fixtures can be divided into manual, pneumatic, hydraulic, pneumatic hydraulic, electric, magnetic, vacuum, etc. according to their power drive mode; according to their application characteristics, they can be divided into general fixtures, special fixtures, adjustable fixtures, combined fixtures, and random There are six categories of fixtures and group fixtures.

     Some design guidelines that need to be followed in the design of fixtures:

1. To understand the entire production, processing and manufacturing methods and processes; do not rely solely on your own knowledge to judge, you must maintain the flexibility of other opinions.

2. Pay attention to the setting of datum plane and datum point, unify the front and back projects, and not contradict each other.

i3. It should be considered that the positioning support must match the processing object and maintain sufficient rigidity.

4. To be as simple and simple as possible; to design from the user's standpoint; to consider the wasteful actions of the operator, and to improve the operability of the manual mechanism.

5. Take safety into consideration and be designed to be safe even if the operation is wrong.

6. Adequate deployment (standard products) should be considered, standard products (commercial products, standard specifications, etc.) should be used more, and special products should be avoided as much as possible.

7. To consider the durability (quenching of parts, etc.) from the relationship between frequency of use and wear.

8. Consider price, precision, ease of installation and durability.

      Under normal circumstances, the design of process assembly jigs mainly involves positioning, clamping, and the expansion and retraction control and adjustment of moving parts in a single direction. Positioning mainly needs to consider how to limit and control the positioning reference, positioning component, positioning method, positioning error and the degree of freedom in the six directions of front, rear, left, right, up and down

      Clamping mainly needs to consider:

1. When the clamping device clamps the workpiece, it should not damage the positioning of the workpiece. For this reason, the direction and focus of the clamping force must be correctly selected.

2. The clamping force should be reliable and appropriate. It is necessary to ensure that the deformation of the workpiece after clamping and the damage of the pressure surface will not exceed the allowable range.

3. The structure of the clamping device is simple and reasonable, the clamping action should be rapid, and the operator is labor-saving and safe.

4. The clamping force or clamping stroke can be adjusted and compensated within a certain range.

      The main realization method of clamping:

1. Spring clamping

2. Hinge clamping

3. Centering and clamping

4. Eccentric clamping

5. Linkage clamping

6. Spiral clamping

7. Oblique wedge clamping

      The realization method of telescopic control and adjustment of forward and backward in a single direction: manual, pneumatic, hydraulic, pneumatic hydraulic, electric, magnetic, vacuum, etc.