Wharbo Precision Manufacturing Co.,Ltd

First, the basic principles of CNC machining fixture design

1, to meet the stability and reliability of the workpiece positioning during use;
2, there is enough load or clamping force to ensure that the workpiece in the fixture on the processing process;
3, to meet the simple and rapid operation of the clamping process;
4. The consumable parts must be structures that can be quickly replaced. When the conditions are adequate, it is better not to use other tools.
5, to meet the fixture in the adjustment or replacement process repeat positioning reliability;
6, as far as possible to avoid the complex structure and costly;
7, as far as possible the use of standard parts as a component part;
8, the formation of the company's internal product systematization and standardization.

Second, fixture fixture design basic knowledge

A good machine fixture must meet the following basic requirements:

1, to ensure the accuracy of the workpiece processing to ensure the accuracy of the key, first of all lies in the correct selection of positioning reference, positioning methods and positioning components, if necessary, positioning error analysis, but also pay attention to the structure of other components in the fixture The effect is to ensure that the fixture meets the machining accuracy requirements of the workpiece.

2. To increase production efficiency The complexity of special fixtures should be compatible with the production capacity. All kinds of quick and efficient fixtures should be used as far as possible to ensure convenient operation, shorten the auxiliary time, and increase production efficiency.

3, the process performance of a special fixture structure to seek simple, reasonable, easy to manufacture, assembly, adjustment, inspection, maintenance and so on.

4, the use of good performance fixture should have sufficient strength and stiffness, the operation should be simple, labor-saving, safe and reliable. Under the premise that objective conditions are allowable and economical and applicable, pneumatic and hydraulic clamping devices should be used as far as possible to reduce the operator's labor intensity. Tooling fixtures should also be easily removed. If necessary, the chip evacuation structure can be set to prevent the chips from damaging the positioning of the workpiece and damaging the tool, so as to prevent the accumulation of the swarf from bringing about a large amount of heat and causing deformation of the process system.

5, economical special fixture should use standard components and standard structures as far as possible, strive to simple structure, easy to manufacture, in order to reduce the manufacturing cost of the fixture. Therefore, the design should be based on the order and production capacity of the fixture program to conduct the necessary technical and economic analysis in order to improve the economic benefits of the fixture in production.


2, the fixture design considerations

Fixture design is generally of a single structure, giving a sensory structure is not very complex, especially now that hydraulic fixtures are popular, so that the original mechanical structure is greatly simplified, but if the design process is not considered in detail will inevitably appear unnecessary trouble:

a) The blank allowance of the workpiece. Causes the blank to be oversized and interferes. So be sure to prepare a rough plan before designing. Allow enough space.

b) Clearance of the chips by the chips. Due to the limited space of the machine tool in the design, the fixture is often designed with a relatively compact space. At this time, the iron chips generated in the machining process are often ignored at the dead ends of the fixture, including the poor flow of the chip liquid. Processing brings a lot of trouble. Therefore, at the beginning of the actual process, we should consider the problems in the processing process, after all, the fixture is to improve efficiency, convenient operation-oriented.

c) The overall openness of the fixture. Ignore openness, causing difficulties for operators to install cards, time-consuming and laborious, and design taboos.

d) The basic principles of fixture design. Each fixture has to undergo numerous clamps and loosen the action, so it may be possible to meet the user's requirements at the beginning, but the addition should have its accuracy maintained, so don't design something that has a flawless principle. Even if you are lucky enough to be able to do so, there will not be long-term sustainability. A good design should be tempered by time.

e) Replaceability of positioning elements. The positioning elements are worn out, so replacement should be considered quick and easy. It is best not to design larger parts.

Accumulation of fixture design experience is very important. Sometimes design is one thing, and it is one thing in practical application. So good design is a process of continuous accumulation and summarization. 

Wharbo precision has extensive experiences of making CNC machining parts,We can design the most convenient and practical fixtures for the production use.You can learn more about us from http://www.wharboprecision.com/.Please feel free to send us a RFQ for machined parts need.