Preparation method of bicycle wheel rim

Abstract

The invention discloses a preparation method of a bicycle wheel rim. A core mould is molded in a containing space enclosed by a wheel rim preprofiling product and two supporting parts, and then is placed in a mould and heated to obtain a wheel rim finished product. The core mould adopts heat shrinkable materials to support the wheel rim preprofiling product to be heated and solidified so as to have a set body; then, high-temperature contraction volume core mould is taken out to help the wheel rim finished product to easily separate from the mould; the core mould can be a thermal expansion material; more thermal expansion materials are utilized to scrabble into the body which accords with the wheel rim preprofiling product and is surrounded by two supporting parts; and the body is expanded by being heated to be matched with the mould to support the wheel rim preprofiling product to be heated and solidified into the set body, thus helping the wheel rim finished product to easily separate from the mould, and taking out thermal expansion materials.

Description

technical field [0001] The invention relates to the technical field of bicycle rims, in particular to a method for making rims from composite materials containing carbon fibers. Background technique [0002] Carbon fibers with good heat resistance and light weight are introduced into polymers to make composite materials with mechanical properties such as tensile strength, flexural resistance, and high toughness. They have been widely used in aerospace industry, transportation, sports equipment, and medical equipment. [0003] For example, China Taiwan announced the No. I308527 invention patent case, which belongs to a kind of manufacturing method of bicycle rim, from figure 1 It is not difficult to find that this method generally includes the following processes: [0004] In step 1a, carbon fiber composite materials are laminated to form a rim blank, and a long and high-temperature-resistant inflatable bag is placed inside the blank; in step 1b, the rim blank with the infla...

AI Technical Summary

Problems solved by technology

[0006] 1. Poor structural strength: from figure 2 It can be seen that the inflatable bag 20 and the pipe fitting 21 are inserted into the empty abdomen position of the rim blank 1 from the air hole 11, and are solidified by heat. Figure 4 The rim is formed into an embryo 1', and the air hole 11 pierced through the side wall of the rim still exists, which has a bad influence on the structural strength of the rim

[0007] 2. The rim is not easy to demould: image 3 It shows that in the mold 30 where the upper and lower molds 31, 32 are merged, a mold cavity 33 conforming to the shape of the rim is formed, and the soft rim blank 1 inserted into the mold cavity 33 maintains a slight distance from the cavity wall. However, after the process of gas filling and heating, a qualitative change occurs, becoming Figure 4 The rigid rim blank 1' is in close contact with the cavity wall of the mold 30; at this moment, the two symmetrical support parts 12 on the periphery of the rim blank 1' will clamp the upper mold 31 with the protruding end 13 to form a wall surface of a corresponding shape, The problem that the embryo 1' of the wheel rim is not easily separated from the mold 30

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