Fixture design problems that should be considered in fixture design
With the development of machining industry, fixture has been paid more and more attention. It has been widely used in the field of machining and has become an indispensable part of machining. Driven by the development of machine tool technology in the direction of high speed, high efficiency, precision, compound, intelligence and environmental protection, fixture technology is developing in the direction of high precision, high efficiency, module, combination, universality and economy.
Problems considered in fixture design
The fixture design generally has a single structure, which makes people feel that the structure is not very complex. In particular, the popularity of hydraulic fixture has greatly simplified its original mechanical structure. However, if it is not considered in detail in the design process, unnecessary trouble will inevitably occur:
1. Blank allowance of workpiece
The blank size is too large, resulting in interference. Therefore, the blank drawing must be prepared before design. Leave enough space
2. Chip removal smoothness of fixture
During the design, due to the limited machining space of the machine tool, the fixture is often designed with a compact space. At this time, it is often ignored that the iron filings generated in the machining process accumulate at the dead corner of the fixture.
Including the poor outflow of chip liquid, which brings a lot of trouble to future processing. Therefore, the problems in the machining process should be considered at the beginning of practice. After all, the fixture is based on improving efficiency and convenient operation
3. Overall opening of fixture
Ignoring the openness makes it difficult for the operator to load the card, which is time-consuming and laborious, and the design is taboo
4. Basic theory and principle of fixture design
Each fixture has to undergo countless clamping and loosening actions, so it may meet the user’s requirements at the beginning, but the additive should have its accuracy retention, so don’t design something contrary to the principle.
Even if we can get away with it now, it will not last long. A good design should withstand the tempering of time.
5. Replaceability of positioning elements
The positioning elements are seriously worn, so quick and convenient replacement should be considered*** Do not design into larger parts
The accumulation of fixture design experience is very important. Sometimes design is one thing, and it is another thing in practical application. Therefore, good design is a process of continuous accumulation and summary.
While considering the problems needing attention in the design of tooling and fixture, the following basic principles of tooling and fixture design shall be adhered to:
1. Meet the stability and reliability of workpiece positioning during use
2. There is enough bearing or clamping force to ensure the machining process of the workpiece on the tooling fixture
3. Meet the simple and fast operation in the clamping process
4. Vulnerable parts * * * are structures that can be replaced quickly. When conditions are sufficient * * * do not need to use other tools for replacement
5. Meet the reliability of repeated positioning of fixture in the process of adjustment or replacement
6. Avoid complex structure and high cost as much as possible
7. Standard parts shall be selected as constituent parts as far as possible
8. Form the systematization and standardization of the company’s internal products