General design method for positioning options of aperture system combined clamp

Abstract

The object of the present invention is to propose a general design method utilizing a computer to design the positioning scheme of the hole system combination fixture, comprising the following steps: input the three-dimensional solid model of the workpiece, the structural dimensions of the base plate and the positioning element to the computer; human-computer interaction to determine the workpiece entity The main positioning datum plane and the candidate side positioning datum plane in the model; the computer projects the side positioning datum to the base plate, and establishes the set of positionable edges E of the workpiece on the base plate of the hole system combination fixture; the computer activates the positioning scheme determination module, Complete the set of all positioning schemes; optimize all the positioning schemes in the set of positioning schemes; the computer displays the three-dimensional solid models of the optimized positioning schemes one by one. Because the present invention utilizes a computer, the design of the positioning scheme is fast and accurate, the work efficiency is greatly improved, and the use of the combined fixture is provided conveniently.

Description

technical field [0001] The invention relates to a general design method for the positioning scheme of a hole system combination fixture. Background technique [0002] Fixtures are devices that ensure reliable positioning and fixing of workpieces. Accurate positioning and reliable fixing of workpieces are basic activities in production operations in many manufacturing processes such as metal cutting, assembly, and inspection. The base plate combination fixture with holes has a base plate with precise spacing of positioning holes and fastening holes. According to the specific shape of the part, a fixture is formed by placing the fixture components on the appropriate positioning holes of the base plate. Due to the advantages of good rigidity, high positioning accuracy and reliability of the fixture components, short assembly time, flexibility and good processing technology of the fixture components, the combined fixture of the hole system base plat...

AI Technical Summary

Problems solved by technology

[0003] Fixtures usually need a plane that can bear the main force in operation as the main positioning datum, which limits the 3 degrees of freedom of the workpiece

The key problem in the design of the clamping and positioning scheme of the combined fixture is to determine the feasible position of the positioning element that limits the other three degrees of freedom

Usually these three degrees of freedom are realized by positioning two or three sides perpendicular to the main datum plane. Since the positioning element of the hole system combination fixture can only be installed on the positioning hole of the foundation plate, the position of the positioning element It cannot be steplessly adjusted according to the contour shape of the workpiece, and the design of the clamping and positioning scheme of the hole system combination fixture is very difficult. This is the main reason why the hole system combination fixture has not been popularized and used more than half a century after its invention

At present, the design of a set of hole system combination fixture components basically depends on the designer's personal experience, intuition and trial and error, which is relatively random. Finally, it is necessary to use adjustable positioning components such as eccentric sleeves to adjust the alignment between the positioning pin and the workpiece. gap, the efficiency is very low, and the positioning accuracy is difficult to guarantee, and the design result is often not optimal

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