JP4567137B2 - Bicycle chain case and bicycle equipped with the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a bicycle chain case and a bicycle including the same.
[0002]
[Prior art]
Various types of battery-assisted bicycles are provided in which the driving force by human power is supplemented by the driving force by a motor. However, not only this type of battery-assisted bicycle but also a general bicycle, an integral molded product is used as a chain case. It was used.
[0003]
[Problems to be solved by the invention]
Therefore, the conventional chain case is long and, therefore, when attaching the chain case to the vehicle body frame, workability is poor, and it is particularly difficult to perform the attachment work in a narrow place. In addition, the chain case had a low degree of design freedom.
[0004]
The present invention is to solve the above problems, is easy mounting workability, moreover an object to provide a and bicycle chain case a high degree of freedom bicycle provided with the same design.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, a bicycle chain case according to the present invention has a through-hole through which a crankshaft is inserted, is fixed to a bicycle base frame, and includes a drive sprocket and at least a portion engaged with the drive sprocket. The inner cover body that covers the chain and the outer cover body that has a through-hole through which the crankshaft is inserted, the front portion is attached to the inner cover body, and the rear portion extends along the chain stay. The outer cover body is attached to the inner cover body so as to be rotatable between a first position in which the rear portion is inclined obliquely upward from the chain stay and a second position in which the rear portion extends along the chain stay. Being able to be. The bicycle chain case further includes a box-shaped casing that houses the auxiliary power unit. The inner cover body is provided with an attachment hole for attaching and fixing the inner cover body to the casing, which is covered by the outer cover body rotated from the first position to the second position. A bicycle including such a bicycle chain case is also included in the spirit of the present invention.
[0006]
With the above configuration, by combining the inner cover body and the outer cover body made of different materials and colors, the degree of design freedom can be increased as compared with the related art.
[0007]
Further, since the chain case is composed of two members, the length is shorter than that of the conventional chain case, and therefore, the chain case can be easily attached even in a narrow place.
[0008]
In addition, when a part of the chain case is damaged, it is conventionally necessary to discard the entire chain case. However, in the present invention, if one of the inner cover body and the outer cover body is damaged, only one of them needs to be replaced. Often, repair costs can be reduced.
[0009]
The present invention can be applied not only to a battery-assisted bicycle but also to a normal bicycle that is not electrically powered.
[0010]
Further, according to the present invention, the outer cover body is configured so that the inner cover is rotatable in a first position where the rear portion is inclined obliquely upward from the chain stay and a second position where the rear portion extends along the chain stay. It may be attached to the body. With such a configuration, since there is a margin in the mounting dimensions, variations in dimensions can be absorbed. Furthermore, it is possible to cope with bicycles of different sizes.
[0011]
In the present invention, a locking projection may be formed on the inner side surface of the outer cover body, and an arcuate locking hole through which the locking projection is inserted may be formed in the inner cover body. In this way, the outer cover body can be configured to be rotatable.
[0012]
A plurality of locking holes are formed around the through hole, and the front side portion of the outer cover body has an insertion hole through which the crankshaft is inserted, and a plurality of engagement holes are formed around the insertion hole corresponding to the plurality of locking holes. A stop protrusion may be formed.
[0013]
The casing further includes a box-shaped casing containing an auxiliary power unit, and the inner cover body is covered with the outer cover body rotated from the first position to the second position. since Runode have mounting holes are provided for fixing attached to the casing, the mounting hole is not exposed to the outside, thereby improving the appearance.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited by the present embodiment.
[0015]
(Embodiment)
FIG. 1 is a side view showing the overall configuration of a bicycle according to the present invention, and FIG. 2 is an exploded perspective view of the vicinity of a drive sprocket. This embodiment is an example in which the present invention is applied to a battery-assisted bicycle. First, a schematic configuration of the battery-assisted bicycle will be described. An auxiliary power unit having a motor or the like is mounted on the body frame 10. The vehicle body frame 10 is configured by assembling a head pipe 11, a down tube 12, a seat tube 13, a seat stay 14, and a chain stay 15 together. The lower end portion of the down tube 12, the lower end portion of the seat tube 13, and the front end portion of the chain stay 15 are connected, and a box-shaped casing 16 containing an auxiliary power unit is attached to the connected portion.
[0016]
A drive sprocket 21 that engages with the chain 20 is attached to the crankshaft 22 in the vicinity of the outer surface on the right side (hereinafter abbreviated as “right side”) of the casing 16 in the traveling direction. A crank 24 having a pedal 23 is attached to both ends of the crankshaft 22. Further, an auxiliary power sprocket 25 to which a driving force from the auxiliary power unit is transmitted and an idler sprocket 26 for applying a constant tension to the chain 20 are disposed in the vicinity of the right outer surface of the casing 16. A small wheel sprocket 28 is attached to a rear hub shaft (not shown) that rotatably supports the rear wheel 27. A chain 20 is wound around the wheel sprocket 28, the drive sprocket 21, the auxiliary power sprocket 25, and the idler sprocket 26. The rear wheel 27 is rotationally driven.
[0017]
A chain case 30 that covers a part of the chain 20 is disposed on the right side of the drive sprocket 21 in the traveling direction. The chain case 30 includes a synthetic resin inner cover body 31 fixed to the casing 16 and a synthetic resin outer cover body 32 attached to the inner cover body 31 so as to be rotatable about a horizontal axis. Yes.
[0018]
Figure 3 is a planar surface view of an inner cover body 31, FIG. 4 is a side view from arrow A side of FIG. 3, FIG. 5 is a taken along line B-B sectional view of FIG. 3, FIG. 6 is taken along line C-C sectional view of FIG. 3, FIG. 7 is a flat plane view of the outer cover member 32, FIG. 8 is a perspective view from the back side of the outer cover member 32, FIG. 9 7 It is DD sectional view taken on the line. A specific structure of the chain case 30 will be described with reference to FIGS. 3 to 9 and FIG. 2.
The outer cover body 32 has a front portion 33 attached to the inner cover body 31 and a longitudinal rear portion 34 that is continuous with the front portion 33 and extends rearward along the chain stay 15 above the chain stay 15. . The rear portion 34 also has a role of covering the upper chain 20. A circular insertion hole 35 through which the crankshaft 22 is inserted is formed in the front portion 33. A ring-shaped convex portion 36 concentric with the insertion hole 35 is formed on the left side in the traveling direction of the front portion 33 (the surface facing the inner cover body 31 and corresponding to the inner side surface of the front portion 33). Is formed. A plurality of (three in this embodiment) locking projections 37 are formed on the convex portion 36 at equal intervals in the circumferential direction. The cross section of the locking projection 37 is L-shaped, and includes a shaft portion 37a and a clamping portion 37b extending from the end portion of the shaft portion 37a toward the center side of the insertion hole 35. An insertion hole 39 is formed at the rear end portion of the rear portion 34, and a screw 40 is inserted through the insertion hole 39 into a fixing bracket (not shown) attached to the chain stay 15 so that the rear portion 34 is formed. Fixed.
[0019]
The inner cover body 31 includes a substantially circular main body 45 and a protrusion 46 protruding rearward. The main body 45 mainly covers the drive sprocket 21, and the protrusion 46 mainly covers the auxiliary power sprocket 25 and the idler sprocket 26. A circular through hole 47 is formed substantially at the center of the main body 45, and the crankshaft 22 is inserted through the through hole 47 and the insertion hole 35 of the outer cover body 32. A ring-shaped convex portion 48 projecting toward the outer cover body 32 is formed on the peripheral portion of the through hole 47 on the right side surface (the surface facing the outer cover body 32) in the traveling direction of the main body 45. In addition, a concave portion 49 that is recessed toward the casing 16 is formed on the outer circumferential portion of the convex portion 48. The recess 49 is formed with a locking hole 50 in which the locking projection 37 of the outer cover body 32 is locked. The locking hole 50 is formed in an arc shape extending along a virtual circle concentric with the through hole 47. A plurality (three in this embodiment) of the locking holes 50 are formed at equal intervals in the circumferential direction on a virtual circumference concentric with the through-hole 47 corresponding to the locking projections 37. The locking hole 50 includes a first locking hole portion 50a and a second locking hole portion 50b that is continuous with the first locking hole portion 50a and has a narrower hole width than the first locking hole portion 50a. The first locking hole portion 50 a has a hole width through which the holding portion 37 b of the locking protrusion 37 can be inserted. On the other hand, the second locking hole portion 50b has a hole width in which the shaft portion 37a of the locking protrusion 37 can be inserted but the clamping portion 37b cannot be inserted. Therefore, after the locking projection 37 is inserted into the first locking hole portion 50a, the shaft portion 37a of the locking projection 37 moves to the second locking hole portion 50b by the rotation of the outer cover body 32. The sandwiching portion 37b comes into contact with and is locked with the peripheral edge portion of the second locking hole portion 50b. As described above, the outer cover body 32 is rotatable between the first position where the rear portion 34 is inclined obliquely upward from the chain stay 15 and the horizontal second position where the rear portion 34 extends along the chain stay. ing.
[0020]
Further, a boss 60 (see FIGS. 2 and 4) protruding toward the casing 16 is formed in the inner cover body 31, and a mounting hole 61 extending in the axial direction is formed in the boss 60. One end of the mounting hole 61 opens to the inner cover body side 31. The attachment hole 61 is formed at a position where the outer cover body 32 is covered by the outer cover body 32 when the outer cover body 32 is rotated to the second position.
[0021]
Next, a method for fixing the chain case 30 configured as described above to the vehicle body frame will be described. First, the inner cover body 31 is fixed to the casing 16. Specifically, the inner cover body 31 is placed outside the casing 16 so that the crankshaft 22 is inserted into the through hole 47 and the boss 60 is made to correspond to the mounting hole 70 (see FIG. 2) formed in the casing 16. To place. Next, the mounting hole 72 of the fixing bracket 71 (see FIG. 2) fixed in advance to the casing 16 is made to correspond to the mounting hole 73 (see FIG. 3) formed in the side surface of the inner cover body 31, and fixed with screws. . At the same time, a tapping screw is inserted into the mounting hole 62 of the boss 61, and the tapping screw is tightened. Thereby, the inner cover body 31 is fixed to the casing 16.
[0022]
Next, the outer cover body 32 is attached to the inner cover body 31. Specifically, as shown in FIG. 10A, the locking protrusion 37 is inserted into the first locking hole portion 50a. At this time, the outer cover body 32 is in a state where the rear portion 34 is inclined obliquely upward as shown by the solid line in FIG. This state is the first position. Next, the outer cover body 32 is rotated to the second position indicated by the phantom line in FIG. At this time, the shaft portion 37a of the locking projection 37 moves from the first locking hole portion 50a to the second locking hole portion 50b. As a result, as shown in FIG. 10A, the holding portion 37 b of the locking protrusion 37 abuts on the peripheral portion of the second locking hole portion 50 b, and the outer cover body 32 is locked to the inner cover body 31. It becomes a state. In such a state, the outer cover body 32 is fixed at the second position by fixing the rear end portion of the outer cover body to the chain stay 15. Thus, the chain case 30 can be fixed to the vehicle body frame.
[0023]
Even in a normal non-electric bicycle, the bicycle can be directly fixed to the body frame using the same fixing bracket as described above.
[0024]
(1) In the above-described embodiment, the battery-assisted bicycle has been described. However, the present invention is not limited to the battery-assisted bicycle, but can be applied to a non-powered bicycle.
[0025]
(2) In the above embodiment, the inner cover body 31 and the outer cover body 32 are both made of synthetic resin, but both or one of the inner cover body 31 and the outer cover body 32 may be made of metal.
[0026]
(3) Although the boss 60 is formed on the inner cover body 31 in the above embodiment, it may be formed on the casing 16.
[0027]
(4) In the embodiment described above, the locking projection 37 is directed toward the center of the insertion hole 35, but may be directed outwardly opposite to this. Further, the locking projection 37 is not limited to the L shape, and may be a T shape.
[0028]
【The invention's effect】
As described above, the present invention has the following effects.
[0029]
(1) The inner cover body and the outer cover body are smaller than conventional chain cases. Therefore, the chain case can be easily attached. Moreover, also in the conveyance stage, many parts (inner cover body and outer cover body) can be packed in a small box, and the conveyance cost can be reduced.
[0030]
(2) If multiple types of inner and outer cover bodies with different materials, colors, and shapes are prepared, the degree of freedom of design can be increased by selecting and combining them appropriately. Can do.
[0031]
(3) When the size of the bicycle is different, it is only necessary to change the outer cover body, and the inner cover body can be shared. In addition, since the outer cover body is rotatably attached to the inner cover body, if the fixed state of the outer cover body is slightly inclined, the outer cover body can be shared by changing the fixing bracket. It becomes possible.
[0032]
(4) When a part of the chain case is damaged, it is conventionally necessary to replace the entire chain case. However, in the present invention, when one of the inner cover body and the outer cover body is damaged, only one of them needs to be replaced. The cost can be reduced well.
[0033]
(5) Even if the inner cover body has a mounting hole, it can be covered with the outer cover body. Therefore, the mounting hole is not exposed to the outside, and the appearance beauty is improved.
[Brief description of the drawings]
FIG. 1 is a side view showing an overall configuration of a bicycle according to the present invention.
FIG. 2 is an exploded perspective view of the vicinity of a drive sprocket.
3 is a planar surface view of an inner cover body 31.
4 is a side view seen from the arrow A side in FIG. 3. FIG.
5 is a cross-sectional view taken along the line B-B in FIG. 3;
6 is a cross-sectional view taken along the line CC in FIG. 3;
7 is a planar surface view of the outer cover 32.
8 is a perspective view seen from the back side of the outer cover body 32. FIG.
9 is a cross-sectional view taken along the line DD in FIG.
10 is a cross-sectional view showing a state in which the locking protrusion 37 is fitted in the locking hole 50. FIG.
11 is a view showing a rotating state of the outer cover body 32. FIG.
[Explanation of symbols]
20: Chain 21: Drive sprocket 22: Crankshaft 30: Chain case 31: Inner cover body 32: Outer cover body 37: Locking protrusion 37a: Locking protrusion shaft part 37b: Locking protrusion pinching part 50: Locking Hole 50a: First locking hole portion 50b: Second locking hole portion

Claims (6)

An inner cover body that has a through-hole through which the crankshaft is inserted, is fixed to the base frame of the bicycle, and covers the drive sprocket and at least the chain that engages with the drive sprocket;
The crankshaft has a through-hole through which the front part is attached to the inner cover body, and the rear part comprises an outer cover body extending along the chain stay,
The outer cover body is attached to the inner cover body so as to be rotatable between a first position where the rear portion is inclined obliquely upward from the chain stay and a second position where the rear portion extends along the chain stay. Be able to be
The bicycle chain case further includes a box-shaped casing that houses the auxiliary power unit,
A bicycle provided with an attachment hole for attaching and fixing the inner cover body to the casing, the inner cover body being covered by the outer cover body rotated from the first position to the second position. Chain case. On the inner side surface of the front portion of the outer cover body, a locking projection having a shaft portion and a clamping portion provided at the tip of the shaft portion is formed,
The inner cover body has a first locking hole portion having a hole width through which the clamping portion can be inserted, and the shaft portion can be inserted through the first locking hole portion, but the clamping portion cannot be inserted. An arcuate locking hole formed with a second locking hole portion having a hole width is formed,
In the first position, the locking projection is positioned in the first locking hole portion, and in the second position, the locking projection is positioned in the second locking hole portion, bicycle chain case according to claim 1, wherein but to be locked in the second locking hole portion. A plurality of the locking holes are formed around the through hole, and the front portion of the outer cover body has an insertion hole through which the crankshaft is inserted, and corresponds to the plurality of locking holes around the insertion hole. The bicycle chain case according to claim 2, wherein a plurality of locking projections are formed. An inner cover body that has a through-hole through which the crankshaft is inserted and covers the drive sprocket and at least the chain engaged with the drive sprocket and is fixed to a bicycle base frame, and a through-hole through which the crankshaft is inserted A chain case comprising a hole and having a front part attached to the inner cover body and a rear part extending along the chain stay;
The outer cover body is attached to the inner cover body so as to be rotatable between a first position in which the rear portion is inclined obliquely upward from the chain stay and a second position in which the rear portion extends along the chain stay. Has been
The chain case further includes a box-shaped casing containing an auxiliary power unit,
A bicycle in which the inner cover body is provided with an attachment hole for attaching and fixing the inner cover body to the casing, which is covered by the outer cover body rotated from the first position to the second position. . On the inner side surface of the front portion of the outer cover body, a locking projection having a shaft portion and a clamping portion provided at the tip of the shaft portion is formed,
The inner cover body has a first locking hole portion having a hole width through which the clamping portion can be inserted, and the shaft portion can be inserted through the first locking hole portion, but the clamping portion cannot be inserted. An arcuate locking hole formed with a second locking hole portion having a hole width is formed,
In the first position, the locking projection is positioned in the first locking hole portion, and in the second position, the locking projection is positioned in the second locking hole portion, The bicycle according to claim 4 , wherein the second locking hole portion is locked to the second locking hole portion. A plurality of the locking holes are formed around the through hole, and the front portion of the outer cover body has an insertion hole through which the crankshaft is inserted, and corresponds to the plurality of locking holes around the insertion hole. The bicycle according to claim 5, wherein a plurality of locking projections are formed.

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