Welding method for frame seat tube and welding auxiliary jig of frame seat tube

Abstract

The invention discloses a welding method for a frame seat tube and a welding auxiliary jig of the frame seat tube. The welding method comprises the following steps that the frame seat tube is assembled with an upper tube and an upper fork; a clamping seat tube is fixed by adopting a quick-dismounting clamping mechanism; and welding beads of the seat tube, the upper tube and the upper fork are correspondingly divided into a left welding bead, a right welding bead, an upper welding bead and a lower welding bead, the left welding bead and the right welding bead of the cross-crossed welding seat tube and the upper tube and the upper fork and the upper welding bead and the lower welding bead of the upper tube and the upper fork are crossed, and finally, the quick-dismounting clamping mechanismis disassembled, the frame is subjected to heat treatment, the spot welding table of the welding auxiliary jig can fix the frame, the rotating and low-speed rotating of the quick-dismounting mechanismis installed at one end of a fixed column, the integral just formed by the fixed column and a rotating column can be inserted into the seat tube, and the fixed column and the seat tube are in close fit connection state. According to the method, the cost investment of an early-stage mold can be reduced, the labor is saved, the productivity is improved, and the roundness of the seat tube can be kept after the seat tube is welded with the upper tube and the upper fork.

Description

technical field [0001] The invention relates to a bicycle welding method, in particular to a bicycle frame seat tube welding method and its auxiliary welding fixture. Background technique [0002] In the production process of bicycle frames, the problem of bending and deformation of pipe fittings is often encountered. The seat tube of bicycle frame needs a relatively long straight tube with high straightness requirements to ensure that the seat post can be easily inserted into the seat tube and can Easy to adjust the height of the cushion. [0003] Generally, the upper fork and the upper tube of men's bicycles are at the same height, and the deformation of the welded rear seat tube is almost symmetrical, although there will still be some small bending deformation. During the heat treatment of the frame, the seat tube will be treated Straightening can meet the needs of use; while the upper fork and upper tube of women's bicycles are not at the same height, and after welding ...

AI Technical Summary

Problems solved by technology

If the heat is too concentrated during the welding process, internal stress will be generated inside the pipe fittings, which will easily become unstable during the next welding process, especially the front and rear solder joints of the seat tube of the women's bicycle frame are more staggered, and the two internal stresses are involved with each other, which is extremely It is easy to cause "S" bends in the front and rear directions of the seat tube. The manual repair of women's bikes is affected by the structural space of the frame, and the operation is relatively difficult.

[0005] The existing way to overcome the deformation of the seat tube of the aluminum alloy bicycle female bicycle is to insert a metal holder with a hardness higher than that of the aluminum alloy into the seat pipe of the female bicycle. To the solid effect of the lining, until the internal stress of the heat-treated frame is eliminated, then pull it out from the seat tube. Since each frame must use the above-mentioned retainer, the retainer takes a long time in the production process and requires batch production. Putting in metal holders, professional equipment is required to insert and pull out the holders. The holders need to be resistant to high temperature (heat treatment together with the aluminum alloy frame), can not be rusted after long-term use, and have good dimensional stability. Stainless steel materials cannot share the same specifications, which requires more mold costs and manpower, and also seriously affects production efficiency

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