JP2014061864A - Transmission folding bicycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transmission for folding bicycles which allows rolling movement in both the forward and backward direction when a folding bicycle folded is moved by rolling by the use of the front and rear wheels superimposed so as to match nearly with each other.SOLUTION: In a transmission mechanism allowing multi-stage transmission through rotation coaxial with the rear wheel of a bicycle, when a gear shift instruction to the position of the highest or lowest speed is given, one gear plate 3 among the gear plates is made to be toothless, and a chain 1 comes in sliding contact with the smooth end surface of the gear plate.

Description

The present invention relates to a folding bicycle transmission mechanism.

When folding a folded bicycle, the front and rear wheels are folded and matched approximately, and when using both wheels to roll and move, the rear wheel can roll and move in the idle direction, but in the opposite direction Since the pedal is fixed by folding, it is impossible to move the pedal. If the pedal is forcibly moved, the chain may come off or a failure may occur.

Therefore, after attaching a small wheel, which is generally used in a shopping cart, to a bicycle seat post holding part or loading part, etc. and folding it, the small wheel is used to roll in both the front and rear directions. In many cases, this small wheel has a small wheel diameter, so it is easy to be affected by the ground such as pebbles and steps, adding mechanisms, increasing weight, and appearance and design of the bicycle It is a difficult point.

When folding a bicycle, the chain is lifted by a link mechanism that interlocks with the folding mechanism from a multi-stage gear assembly that rotates coaxially with the rear wheel, and the rear wheel can be rotated in both the front and rear directions (see Patent Document 1). However, there are difficulties such as structural size, complexity, weight increase, and appearance.

Patent Document 1: Japanese Patent Application Laid-Open No. 2001-171586 “Folding Bicycle”

In view of the conventional difficulties as described above, instead of installing a new mechanism, it is only necessary to make a small improvement to the already installed multi-stage transmission, and the folded bicycle can be used in both the front and rear directions using its front and rear wheels. An object of the present invention is to provide a folding bicycle transmission mechanism that can be rolled and moved and that eliminates the above-mentioned difficulties.

In order to achieve the above object, in a multi-speed shift mechanism that rotates coaxially with the rear wheel of a bicycle, when the shift instruction is given to the position of the highest speed side or the lowest speed side, the rear wheel is normal to the chain. A speed change mechanism for a folding bicycle, characterized in that in addition to idling in one direction, means for idling in the opposite direction is also provided.

As a means for idling, gears with different number of teeth are stacked in multiple stages, and one of the gear plates of the exterior multi-stage transmission mechanism that changes speed by changing the combination of the gear and chain is made a toothless gear, and its smooth gear plate end face 2. The folding bicycle transmission mechanism according to claim 1, wherein the chain is in sliding contact with the top.

As another idling means, one of the gear plates of the external multi-stage transmission mechanism of the preceding paragraph is divided into two concentric circles, and the folding part described above is characterized by sliding contact or ball rolling contact at the divided part Bicycle speed change mechanism.

Further, as another idling means, in an internal multi-stage transmission mechanism that is shifted by changing the combination of gears and gears having different numbers of teeth, when a gear shift instruction is given to the highest speed side or the lowest speed side position, The folding bicycle transmission mechanism according to the above-described, characterized in that it is idled by not providing a combination.

When trying to finish running with a simple mechanism with the above-mentioned simple modifications added to the existing speed change mechanism without adding a special mechanism, the shift speed shift lever can be used to set the maximum speed side or the minimum speed side. If it is folded, the bicycle can be moved in both forward and backward directions using the front and rear wheels.

Mechanism of the embodiment relating to the folding bicycle transmission mechanism of the present invention An example of the shift lever display section in the embodiment of the present invention

FIG. 1 shows the concept of an embodiment according to the present invention, and FIG. 1 (a) shows a cross-sectional view of a multi-stage gear assembly of a bicycle exterior transmission, which is originally a 9-speed gear. It is an assembly that has been improved to 8 gears and 1 gear for idling, and the hatched part of each gear plate shows that there are gear teeth. 1 is a chain, 2 is a gear plate for transmission of 8 steps, 3 is a gear plate without teeth, and FIG. 1 shows the state where the chain 1 is just shifted to the position of the gear plate 3. The chain 1 is in a sliding contact state on the smooth end surface of the gear plate 3 having no teeth, and the pedal is fixed in the folded state. Therefore, even if the chain is fixed, the rear wheel can be rotated in both the front and rear directions.
In this example, a chain slip prevention plate 5 is added to the gear plate 3 so that the chain does not come off.

In FIG. 1 (b), instead of the gearless plate 3 of FIG. 1 (a), there is a tooth, but a ball rolling contact type gear plate in which a bearing ball is inserted into a concentric circle divided into two parts. In this embodiment, consideration is given to minimizing the wear of the chain and the like when it is moved for a long distance and for a long time while being pushed.

FIG. 2 shows the display portion of the shift lever in the embodiment of FIG. 1, and the triangle mark shows which gear plate position the current gear shift is. In FIG. 2, it is shown that it is in the position of F (Fold: Fold) of the leftmost first stage just like the position of the chain of FIGS. 1 (a) and 1 (b).

In FIG. 1, when traveling, the gear plate 2 for shifting from the second to ninth gears is used as an eight-speed shift, and when folded, the position of the first F is indicated by the shift lever as shown in FIG. When the bicycle is folded, the bicycle rotates freely in both the front and rear directions between the rear wheel and the chain, and the folded bicycle using the front and rear wheels can be rolled and moved in both the front and rear directions.

The present invention is used in the industry of manufacturing folding bicycles.

DESCRIPTION OF SYMBOLS 1 Chain 2 Gear plate for transmission 3 Toothless gear plate 4 Toothed gear plate with bearing ball inserted 5 Chain slip prevention plate

Claims (4)

In a speed change mechanism capable of multi-speed shifting that rotates coaxially with the rear wheel of the bicycle, when the shift instruction is given to the position of the highest speed side or the lowest speed side, A folding bicycle transmission mechanism characterized in that means for idling in the reverse direction is provided. 2. The folding bicycle shifter according to claim 1, wherein one of the gear plates of the multi-stage transmission mechanism is a toothless gear plate as the idling means, and the chain is in sliding contact with the end surface of the smooth gear plate. mechanism. 2. The folding bicycle according to claim 1, wherein one of the gear plates of the multi-stage speed change mechanism is divided into two concentric circles as the idling means, and is in sliding contact or ball rolling contact at the divided portion. Transmission mechanism. In the internal multi-stage transmission mechanism that changes gears by changing the combination of gears and gears with different number of teeth as idle means, when a gear shift instruction is given to the highest speed side or the lowest speed side, no gear combination is provided. The folding mechanism for a folding bicycle according to claim 1, wherein:

Images