KR102495655B1 - Device for preventing chain separation of foldable bicycle - Google Patents

Abstract

The present invention relates to a chain separation prevention device for a foldable bicycle, comprising: a body portion in which a drive sprocket is installed, a rear wheel portion which rotates downward with respect to the body portion and is folded forward, and a driven sprocket is installed therein, and the drive sprocket; A device applied to a folding bicycle including a chain connecting the driven sprocket to prevent the chain from being separated due to a shortening of the distance between the driving sprocket and the driven sprocket when the rear wheel part is folded, which is fixed to the rear wheel part A fastening part, an extension part extending from the fastening part, and a locking part formed at the end of the extension part and disposed inside the chain, so that when the rear wheel part is folded, the distance between the drive sprocket and the driven sprocket is shortened and loosened. Ji provides a chain detachment prevention device for a foldable bicycle in which tension is maintained by the chain being spaced outward by being caught on the hooking portion.

Description

Chain detachment prevention device for foldable bicycle {Device for preventing chain separation of foldable bicycle}

The present invention relates to a chain separation prevention device for a folding bicycle, and more particularly, to a chain of a folding bicycle capable of preventing the chain from being separated from a sprocket due to a shortened distance between a driving sprocket and a driven sprocket when the folding bicycle is folded. It is about the escape prevention device.

As the number of people riding bicycles for a healthy life has increased, various types of bicycles have been developed. In particular, in recent years, folding bicycles that can minimize the volume when carrying or storing bicycles are in the spotlight.

Folding bicycles may be classified into one-stage folding, two-stage folding, and three-stage folding according to the number of folding parts.

For example, in the case of a three-stage folding bicycle, the rear wheel portion is folded forward with respect to the body portion, the front wheel portion is folded laterally to overlap the rear wheel portion, and the handle portion is folded downward to minimize the volume. In this case, a drive sprocket is installed on the body, a driven sprocket is installed on the rear wheel, and the drive sprocket and the driven sprocket are connected to each other by a chain.

However, most of the foldable bicycles described above do not fold the rear wheel around the rotational axis of the drive sprocket, but rather around the hinge located at the rear, so the distance between the drive sprocket and the driven sprocket is shortened when the rear wheel is folded. There is a problem in that the sprocket becomes loose and is separated from the sprocket.

In addition, as shown in FIG. 1, since the distance between the driving sprocket 21 and the driven sprocket 35 is structurally shorter than that of a general bicycle, when the driven sprocket 35 is configured in multiple stages, the chain ( 40) fails to maintain an aligned state with the driven sprocket 35 and becomes twisted, which also acts as a cause of chain detachment.

If the chain is detached, when the folded bicycle is unfolded again, the chain is not correctly coupled to the sprocket, so the bicycle cannot be operated immediately, and since the chain must be coupled to the sprocket by hand, it is inevitably cumbersome, such as getting oil on the hands.

The present invention has been made to solve the above-mentioned problems of the prior art, and is a foldable bicycle that prevents the chain from being separated from the sprocket because the chain is not loosened even if the distance between the driving sprocket and the driven sprocket is shortened when the folding bicycle is folded. An object of the present invention is to provide a chain separation prevention device.

As a means for solving the above-mentioned technical problem,

The present invention is foldable including a body portion in which a drive sprocket is installed, a rear wheel portion which is rotated downward with respect to the body portion and is folded forward, and a rear wheel portion in which a driven sprocket is installed, and a chain connecting the drive sprocket and the driven sprocket. A device applied to a bicycle to prevent the chain from being separated due to a shortening of the distance between the driving sprocket and the driven sprocket when the rear wheel portion is folded, comprising: a fastening portion fixed to the rear wheel portion; and an extension extending from the fastening portion. and a hooking part formed at an end of the extension part and disposed inside the chain, so that when the rear wheel part is folded, the distance between the driving sprocket and the driven sprocket is shortened so that the chain, which is loosened, is caught on the hooking part and moves outward. It provides a chain separation prevention device for a folding bicycle, characterized in that the tension is maintained by being spaced apart.

In this case, the hooking portion may be bent in an L-shape or a C-shape, and its end may be spaced apart from the chain by 5 to 15 degrees inward.

In this case, a transmission for adjusting the gear ratio is installed in the rear wheel unit, a chain tensioner for maintaining the tension of the chain that is changed when the gear ratio is adjusted is coupled to the transmission, and the fastening part may be fixed to the chain tensioner.

According to the present invention, when the rear wheel portion is folded with respect to the body portion of a folding bicycle, the distance between the drive sprocket and the driven sprocket is shortened, so that the loose chain is spaced outward by a predetermined distance by the extension portion and the hanging portion, thereby increasing the tension of the chain. can be maintained to prevent departure.

In addition, the hooking part is bent in an L- or U-shape, and its end is spaced 5 to 15 degrees inward from the chain in the unfolded state of the folding bicycle, so that interference with the chain is avoided during operation of the folding bicycle and when folding It can effectively prevent the chain from coming off.

1 is a schematic diagram showing a coupling structure of a driving sprocket, a driven sprocket and a chain of a folding bicycle;
2 is a perspective view of a chain separation prevention device for a folding bicycle according to a preferred embodiment of the present invention;
Figure 3 is a front view of the chain separation prevention device shown in Figure 2;
Figure 4 is a side view showing a folding bicycle to which the chain separation prevention device shown in Figure 2 is applied;
Figure 5 is a side view showing the process of folding the rear wheel portion of the foldable bicycle shown in Figure 4;
6 is a structural diagram showing a folded state of the folding bicycle shown in FIG. 4;
7 is a partially enlarged view showing the rear wheel of the folding bicycle shown in FIG. 6;

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily practice with reference to the accompanying drawings. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein. In addition, in order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are used to describe similar parts throughout the specification.

2 is a perspective view of a chain detachment prevention device for a folding bicycle according to a preferred embodiment of the present invention, FIG. 3 is a front view of the chain detachment prevention device shown in FIG. 2, and FIG. 4 is a chain detachment prevention device shown in FIG. A side view showing the applied folding bicycle, Figure 5 is a side view showing the process of folding the rear wheel portion of the folding bicycle shown in Figure 4, Figure 6 is a structural diagram showing a folded state of the folding bicycle shown in Figure 4, Figure 7 is a diagram 6 is a view showing a partially enlarged rear wheel of the foldable bicycle.

2 to 7, a chain detachment prevention device 100 for a folding bicycle according to a preferred embodiment of the present invention (hereinafter referred to as 'chain detachment prevention device 100') is applied to a folding bicycle 10 Hereinafter, the foldable bicycle 10 will be described first, and based on this, the present invention will be described in detail.

The folding bicycle 10 may use a single-stage folding bicycle, a two-stage folding bicycle, and a three-stage folding bicycle, and is not particularly limited, but is structurally a folding bicycle having a short distance between a driving sprocket and a driven sprocket and capable of multi-stage shifting, or When the bicycle is folded, the distance between the driving sprocket and the driven sprocket is shortened and the chain becomes loose. Here, a three-stage folding bicycle having such a structure will be described as an example.

The folding bicycle 10 includes a body portion 20, a rear wheel portion 30, and a chain 40, and may further include a front wheel portion 50, a handle portion 60, and a saddle portion 70. there is.

The body part 20 has a frame structure of a predetermined shape and is disposed in the front and rear directions of the folding bicycle 10, and a drive sprocket 21 rotatably installed at the bottom to receive user's force through the pedal 22 .

The rear wheel part 30 is a part installed at the rear end of the body part 20, and is rotatably inside the seat stay 31, the chain stay 34, and the seat stay 31 and the chain stay 34. It may include a coupled rear wheel (32). In this case, a driven sprocket 35 is installed on the rotation shaft of the rear wheel 32.

The rear wheel portion 30 rotates downward with respect to the body portion 20 around the first hinge portion 33 formed behind the rotation axis of the drive sprocket 21 and is folded forward.

On the other hand, when the driven sprocket 35 is composed of a plurality of sprockets having different diameters and is capable of shifting, the driven sprocket 35 includes a transmission 36 for adjusting the gear ratio and the tension of the chain 40 that is changed when adjusting the gear ratio. A chain tensioner 37 for adjusting the may be additionally installed.

The chain 40 connects the drive sprocket 21 and the driven sprocket 35 to transmit power of the drive sprocket 21 to the driven sprocket 35 .

The front wheel part 50 is a part installed at the front end of the body part 20, and may include a front fork 51 and a front wheel 52 rotatably coupled between the front fork 51. The front wheel portion 50 rotates to one side with respect to the body portion 20 around the second hinge portion 53 formed at the front end of the body portion 20 and is folded rearward.

The handle part 60 is a part coupled to the top of the front wheel part 50, and may include a handle support 61 and a handle bar 62 provided at the top of the handle support 61. The handle part 60 is folded downward by rotating to one side around the third hinge part 63 formed at the upper end of the front wheel part 50 .

The saddle part 70 is a part coupled to the upper part of the rear end of the body part 20, and may include a seat post 71 and a saddle 72 coupled to the upper part of the seat post 71.

In the above, the folding bicycle 10 has been described.

For reference, when the rear wheel portion 30, the front wheel portion 50, and the handle portion 60 of the foldable bicycle 10 are all folded, the shape shown in FIG. 6 is obtained, and the rear wheel portion 30 and the front wheel portion 50 And when the handle portion 60 is shown in a folded and overlapping state as it is, the operating structure of the chain detachment prevention device 100, which is a technical feature of the present invention, may not be clearly understood, so in FIG. 6, the chain detachment prevention device 100 ) and related components are highlighted by bold marking, and the rest of the components are displayed in the form of a structure diagram with relatively dim markings.

Hereinafter, the chain separation prevention device 100 applied to the folding bicycle 10 will be described in detail.

The chain separation prevention device 100 includes a fastening part 110, an extension part 120 and a hooking part 130 as shown in FIGS. 2 and 3.

The fastening part 110 is a part for fixing the chain separation prevention device 100 to the folding bicycle 10, and may be fastened to the rear wheel part 30 with bolts, nuts, etc. in the form of a pair of rings. On the other hand, when the folding bicycle 10 further includes the transmission 36 and the chain tensioner 37 as in this embodiment, the fastening part 110 is attached to both sides of the chain tensioner 37 using bolts and nuts, respectively. can be fixed

The extensions 120 are parts for spaced apart a predetermined distance from the chain 40, which is loosened when the folding bicycle 10 is folded, and each extends from the fastening part 110. The extension length of the extension part 120 may be appropriately adjusted within a range in which the tension of the chain 40 is maintained without loosening when the folding bicycle 10 is unfolded.

The hanging part 130 is a part where the chain 30 is caught when the folding bicycle 10 is folded, and is formed at the end of the extending part 120 extending in parallel.

The hooking part 130 may include a bent part 131 bent in an approximate L or U shape at the end of the extension part 120 and a hanging bar 132 formed at the end of the bent part 131. . In the drawing, as an example of the bent portion 131, a shape formed in a U-shape is presented as an example. The hanging bar 132 is formed at the end of the bent portion 131, and the longitudinal direction of the hanging bar 132 is formed in the left and right directions based on the forward direction of the bicycle. As the bent portion 131 is bent in an L- or C-shape, the hanging bar 132 is positioned in non-contact with the chain 40 on the inside of the chain 40 in the unfolded state of the folding bicycle 10 as shown in FIG. is placed on Therefore, the chain 40 is spaced apart from the hanging bar 132 while being disposed between the extension parts 120, so that interference by the hanging part 130 does not occur, and as shown in FIGS. 5 and 6, a folding bicycle ( 10) can be spaced outward while being caught on the hanging bar 132 only when it is folded.

When the folding bicycle 10 is in a unfolded state, when the hanging bar 132 is disposed inside the chain 40 so that it does not come into contact with the chain 40, the hanging bar 132 moves inwardly with respect to the chain 40, for example, They may be spaced approximately 5 to 15 degrees apart. If the arrangement angle of the hanging bar 132 is less than 5 degrees, the hanging bar 132 may interfere with the chain 40 due to vibration generated during operation of the folding bicycle 10, and if it exceeds 15 degrees, the folding bicycle 10 ) In order to maintain the tension of the chain 40 when folding, the extension part 120 is excessively long, which can damage the appearance, so 5 to 15 degrees is preferable.

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When configured as described above, when the foldable bicycle 10 is completely folded (see FIGS. 6 and 7), the extension part 120 has an angle of approximately θ (5 to 15 degrees) with respect to the coupling axis of the fastening part 110. can be placed within the range. Even in this case, if the extension part 120 is out of the above angle range, the chain 40 interferes with the driven sprocket 35, the chain tensioner 37, or a chain part coupled thereto, or maintains the tension of the chain 40. For this purpose, the extension 120 may cause problems such as protruding outwardly of the rear wheel 32 due to excessive length.

Above, the chain separation prevention device 100 has been described. Hereinafter, the operation of the chain separation prevention device 100 will be described.

In the unfolded state of the folding bicycle 10, the chain separation prevention device 100 has the chain 40 inserted between the extension part 120 and the hooking part 130, and the hooking bar 132, which is the end of the hooking part 130, maintains a state not in contact with the chain 40 (see FIG. 4). Therefore, even if the user drives the folding bicycle 10, the extension part 120 or the hooking part 130 does not interfere with the chain 40 and collide with it.

In addition, in the process of folding the rear wheel portion 30 of the folding bicycle 10 forward around the first hinge portion 33, as shown in FIG. 5, the chain 40 is caught on the hanging bar 132. Since the rear wheel portion 30 is folded, there is no room for the chain 40 to be separated.

In addition, when the foldable bicycle 10 is completely folded (see FIG. 6), the rear wheel portion 30 is folded forward with respect to the body portion 20, and the distance between the driven sprocket 35 and the drive sprocket 21 increases. As a result, the chain 40 is loosened, but the loosened chain 40 is caught on the hanging bar 132 and is spaced outward by approximately the length of the extension part 120, so that the tension of the chain 40 is maintained and the sprocket (21) does not deviate from (35).

In the above, preferred embodiments of the present invention have been described in detail with reference to the drawings. The description of the present invention is for illustrative purposes, and those skilled in the art will understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention.

Therefore, the scope of the present invention is indicated by the following claims rather than the above detailed description, and all changes or modifications derived from the meaning, scope, and equivalent concepts of the claims are included in the scope of the present invention. should be interpreted as

10: folding bicycle 20: body
21: drive sprocket 22: pedal
30: rear wheel part 31: seat stay
32: rear wheel 33: first hinge
34: chain stay 35: driven sprocket
36: transmission 37: chain tensioner
40: chain 50: front wheel
51: front fork 52: front wheel
53: second hinge part 60: handle part
61: handle support 62: handle bar
63: third hinge part 70: saddle part
71: seatpost 72: saddle
100: chain separation prevention device 110: fastening part
120: extension part 130: hanging part

Claims (3)

Applied to a folding bicycle that includes a body on which a drive sprocket is installed, a rear wheel portion that rotates downward and folds forward with respect to the body, and has a driven sprocket installed thereon, and a chain connecting the drive sprocket and the driven sprocket. As a device for preventing the chain from being separated when the rear wheel part is folded, the distance between the drive sprocket and the driven sprocket is shortened,
Fastening part fixed to the rear wheel part;
an extension portion extending from the fastening portion; and
Hooking part formed at the end of the extension part
Including,
The hanging portion includes a hanging bar disposed inside the chain while the longitudinal direction is formed in the left and right directions,
When the foldable bicycle is unfolded, the hanging bar is disposed inside the chain without contacting the chain,
When the rear wheel part is folded, the distance between the driving sprocket and the driven sprocket is shortened, and the chain, which is loosened, is caught on the hanging bar and is spaced outward, thereby maintaining tension. According to claim 1,
The chain separation prevention device for a foldable bicycle, characterized in that the hanging portion includes a bent portion formed by bending at an end of the extension portion in an L-shape or a C-shape, and the hanging bar is formed at an end of the bent portion. According to claim 1 or 2,
A transmission for adjusting the gear ratio is installed on the rear wheel portion, a chain tensioner for maintaining the tension of the chain that is changed when adjusting the gear ratio is coupled to the transmission, and the fastening part is fixed to the chain tensioner. chain breakaway prevention device.

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