Frame specification conversion structure

Abstract

The invention discloses a frame specification conversion structure. The frame specification conversion structure comprises a five-way connecting pipe which is used for being connected with a lower branch pipe, a middle pipe and a lower pipe, wherein a groove-shaped pipe opening is formed in the five-way connecting pipe in the axial direction of the middle pipe. The frame specification conversion structure further comprises an axle hole pipe which penetrates through the groove-shaped pipe opening and is used for fixing a crankset, wherein a detachable adjusting block is further arranged on the side portion of the groove-shaped pipe opening, the cross section of the adjusting block is a crescent face, and when the adjusting block is inserted into one side of the groove-shaped pipe opening, a round opening which facilitates fixation of the axle hole pipe is formed by the crescent face and the groove-shaped pipe opening. The adjusting block comprises two side portion clamping blocks, a middle clamping block arranged between the two side portion clamping blocks, and a bolt, wherein the two side portion clamping blocks are provided with opposite slopes respectively, the middle clamping block comprises conical faces corresponding to the slopes of the two side portion clamping blocks, and the bolt movably penetrates through one of the side portion clamping blocks and the middle clamping block and then is fixed to the other side portion clamping block in a screwed mode. Due to the fact that the frame specification conversion structure can adjust the height of the axle hole pipe which is used for fixing the crankset, the requirement that the same frame is used in cooperation with wheels with different sizes can be met.

Description

technical field [0001] The invention relates to a bicycle frame structure, in particular to a bicycle upper frame specification conversion structure. Background technique [0002] At present, each bicycle has its own wheel size. Wheels of different sizes are equipped with different types of bicycles for different groups of people in different riding environments. If a bicycle is to be used by different groups of people (such as adults and children) , or men’s and women’s), and the special riding needs in a variety of usage environments, it is necessary to be equipped with wheels of different sizes. In addition, it is necessary to reduce or increase the height of the fixed chainring (connected to the pedals) to meet the needs of different groups of people. However, in the prior art, it is impossible to reduce or increase the height of the fixed chainring by connecting the bottom bracket pipe fittings of the front fork pipe, the middle pipe, the down pipe and the shaft hole pi...

AI Technical Summary

Problems solved by technology

[0002] At present, each bicycle has its own wheel size. Wheels of different sizes are equipped with different types of bicycles for different groups of people in different riding environments. If a bicycle is to be used by different groups of people (such as adults and children) , or men’s and women’s), and the special riding needs in a variety of usage environments, it is necessary to be equipped with wheels of different sizes. In addition, it is necessary to reduce or increase the height of the fixed chainring (connected to the pedals) to meet the needs of different groups of people. However, in the prior art, it is impossible to reduce or increase the height of the fixed chainring by connecting the front fork tube, the middle tube, the down tube and the shaft hole tube.

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