JPH1067364A - Structure of chain case mounting part for bicycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve case fitting workability and working efficiency by decreasing the number of screwing positions. SOLUTION: A case body 2 is provided, which covers one side of a chain wheel and one side of a chain. The front end part 2A of the case body 2 is fitted through a fitting hardware 15 fixed at the boss part of a crank shaft, and the case body 2 is jointed and positioned at the fitting hardware 15 with an engaging means constituted of an engaging piece provided at one end of the fitting hardware 15 and an engaging recessed part in which the engaging piece is fitted and engaged. The case body 2 positioned by a screwing means constituted of a screw inserting hole 7 which is formed in the case body 2, a threaded hole formed in the fitting hardware 15, and a fixing screw 20 which passes through both the holes is tightened and fixed at the fitting hardware 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a mounting portion of a half-side case type chain case which covers outer surfaces of a bicycle chain and a chain wheel.

[0002]

2. Description of the Related Art FIG.
The following are known. This chain case 3
Reference numeral 1 denotes mounting brackets 33, 34 on a frame 32 of the bicycle 30.
And a large part of one side surface of a chain wheel 37 fixed to a crankshaft 36 (see FIGS. 11 and 12) rotatably mounted on a boss 35 at the lower center of the frame 32. And the chain 3
8 is a half-sided case shape that covers one side surface of the upper portion 38A.

[0003] In the chain case 31, an edge flange 31B is protrudingly provided on the back side of the front plate 31A, and a crank 39 (FIG.
1, see FIG. 12). A tongue-shaped mounting portion 41 extending in a direction toward the axis of the crankshaft 36 is projected from two upper and lower portions of the edge flange 31B on the front side of the chain case 31. The mounting portion 41 includes a chain wheel. 37 is provided with a long mounting hole 42 in the circumferential direction. The rear end of the chain case 31 has a mounting hole 43.
Is provided.

As shown in FIGS. 11, 12, and 14, the front mounting bracket 33 has a substantially rectangular shape, and a mounting hole 44 for the boss 35 is provided at the center. The screw holes 45 are provided at the upper and lower ends.
As shown in FIGS. 11 and 12, the mounting bracket 33 is externally fitted to a screw portion 46 provided on the boss 35 of the frame 32 and is fixed by a ring nut 47.

[0005] The chain case 31 is mounted on a bicycle frame 32 which is conveyed in an upright state during the assembling work in the flow stroke, and has front ends fixed with screws 48 and 4.
By 8, it is fixed to the screw holes 45, 45 of the mounting bracket 33. As another conventional example, as shown in FIGS. 16 and 17, a chain case 31 is a half-surface case type that covers upper and lower side surfaces of a chain wheel 37 and a chain 38, and a screw is formed on upper and lower portions of an edge flange 31B at a front end portion. Insert holes 42 are respectively provided, and upper and lower ends of the mounting bracket 33 are bent so as to be positioned parallel to and inside the case edge flange 31B to form a mounting portion 49, and a screw hole 45 is provided. As shown in FIG. 17, the chain case 31 is fixed by fixing screws 48 from above and below.

[0006]

However, the above-mentioned prior art has a problem that both the former and the latter have many places to be fixed by screws, and the efficiency of the operation of attaching the chain case to the mounting bracket is poor. If only the screw is fixed, the mounting hole 42 of the chain case 31 and the screw hole 4 of the mounting
However, it is difficult to align the positions 4 and 45, and the assembling operation takes time.

[0007] In particular, when screws are fixed to a bicycle transported in an upright state from below, it is quite difficult to align the holes and screw the screws using a tool. SUMMARY OF THE INVENTION The present invention has been made in view of the above-described circumstances, and has as its object to reduce the number of screwed portions, thereby improving the workability and efficiency of mounting the case. An object of the present invention is to provide a structure of a mounting portion of a bicycle chain case that can facilitate alignment of holes.

[0008]

According to the present invention, the following technical measures have been taken in order to achieve the above object. In other words, the bicycle includes a case body that covers one side of the chain wheel and one side of the chain, and the front side of the case body is attached through a fixture fixed to a boss of a crankshaft. In the structure of the attachment part of the chain case,
Latch means for connecting the case body to the fixture by engaging the fixture and the case body with each other and positioning the case body at the attachment position; and screwing means for fastening and fixing the positioned case body and the fixture. It is characterized by having.

Further, in the present invention, the latching means includes a latching piece provided at one end of the fixture, and a latching recess provided at a peripheral edge of the case body and into which the latching piece fits. The screwing means has a screw hole provided at the other end of the attachment, and a screw insertion hole provided in the case body corresponding to the screw hole. According to this, the case main body is connected to the mounting tool by the hooking means, and after positioning, the mounting tool and the chain case are connected by the fastening means using a fastening member such as a screw, and the bicycle is mounted on the bicycle. Since the front part of the chain case is attached, the front part of the chain case can be fixed even if the number of fastening points with screws is reduced, and when fixing the screws, the case body is positioned by the locking means. Since the screws are inserted, the screws can be easily inserted and screwed, and the mounting work efficiency and the work efficiency can be improved.

According to the present invention, the hooking piece is provided at an upper end portion of the mounting tool, a hooking recess is formed at an upper portion of the case body, and the screw hole is provided at a lower end portion of the mounting tool. The insertion hole is provided on the lower side of the case main body. In this case, when the chain case is assembled in the flow stroke, the chain is relatively difficult to assemble with the bicycle transported in the upright state. In the upper part of the case (the lower side in the upright state)
Easy engagement work by the latching recess and latching piece,
An insertion hole and a screw hole are arranged on the lower side of the chain case (the upper part in the upright state), so that fastening by screws can be facilitated. Further, the present invention includes a case main body that covers one side of the chain wheel and one side of the chain, and the front side of the case main body is attached via a fixture fixed to a boss of a crankshaft. In the structure of the attachment portion for a bicycle chain case according to the above, the one side of the attachment is inserted into and engaged with at least one of the upper and lower sides of the periphery of the front portion of the case body, and the case body is supported by the attachment. Screwing means for providing a mating groove, providing a fitting portion between the fixture and the case body for positioning the case body with respect to the fixture by uneven fitting, and fastening and fixing the positioned case body and the fixture. Are provided on the upper and lower sides of the front part of the case body.

According to this, the case main body is supported not only by fixing by screwing but also by inserting a fitting into the engaging groove, so that the screw fixing portion can be reduced, and the fitting can be performed. Positioning of the case main body by the portion facilitates the alignment of the screw holes, thereby improving the mounting workability. Further, according to the present invention, the screwing means includes:
A screw hole formed in the attachment, and a screw insertion hole provided in the case body corresponding to the screw hole, wherein the fitting portion is provided at a position where the screw hole and the screw insertion hole are formed. As a feature, the positioning by the fitting portion is performed at the screw fixing portion, and the alignment between the screw hole and the screw insertion hole is reliably performed.

The present invention is characterized in that the engaging groove is formed at least on the upper side of the case main body, and the screwing means is provided on the lower side of the case main body. At the time of mounting the chain case in the flow stroke, the upper end of the chain case, which is relatively difficult to assemble (the lower side in the upright state) with respect to the bicycle transported in the upright position, inserts the fitting into the engaging groove. An insertion work and a screw hole are arranged on the lower side of the chain case (the upper part in the upright state) to facilitate fastening by screws.

Further, the present invention is characterized in that the engaging groove is formed over the front end of the case main body, and the engaging portion of the attachment is formed corresponding to the engaging groove. ,
Accordingly, the case body can be more reliably supported by inserting and engaging the attachment into the engagement groove. Further, the case main body is preferably made of a synthetic resin such as ABS, PP, or polycarbonate.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 5 show a first embodiment of a bicycle chain case 1 according to the present invention.
The chain case 1 is made of a synthetic resin, for example, an ABS resin, and includes a case body 2 that covers most of the lateral outer surface of the chain wheel (see FIG. 10) and the outer surface of the upper chain (see FIG. 10). A front end 2 of the case body 2
A is attached via a fitting (fixing) 15 fixed to the boss of the crankshaft, and the rear end 2B of the case body 2
Is a half-surface case type which is attached to the rear end of the frame via a mounting bracket (see FIG. 10).

The case body 2 is on the back side (left and right inner sides) of the front plate 3 and the peripheral edge of the front plate 3 excluding the front lower portion and the rear end portion.
A chain (see reference numeral 38 in FIG. 10) passes through a portion without the flange 4 so that the crankshaft and the crank are passed through the center of the front part of the front plate 3. An insertion hole 5 is provided, and a mounting hole 6 of a rear mounting bracket 60 is provided on the front plate 3 of the rear end 2B.

The case body 2 is provided with a fixing screw insertion hole 7 in parallel with the front plate 3 at a lower thick portion 4A, which is thicker below the front end, and is thicker above the front end. A latching recess 8 is provided in the upper thick portion 4B so that the fixture 15 can be inserted and locked from the back side. This latching recess 8 is shown in FIG.
As shown in FIG. 5, the thick rim 4 </ b> B is recessed outward from the left and right inner side surfaces. A notch 9 serving as an insertion inlet for the recess 8 is formed, and retaining walls 11 and 12 are formed at the front end and the rear end of the concave 8 so as to close the opening of the concave 8. Recesses 13 and 14 in the front-rear direction are formed at the front and rear ends of the retaining recess 8.

As shown in FIG. 1 and FIG. 3, the mounting bracket 15 is shaped like a letter when viewed from the side, and is fitted to a boss portion of a crankshaft (see FIGS. Hole 16
Are provided, and both ends are on the case front plate 3 side (left and right outer sides)
The mounting piece 17 is bent at a right angle to the lower end side and is screwed to the case main body 2.
Are provided corresponding to the screw insertion holes 7 of the lower thick portion 4 </ b> A of the edge flange 4. At the upper bent portion of the mounting bracket 15, there is provided a latching piece 19 which is widened in the front-rear direction, and the latching piece 19 and the recess 8 of the case body 2 constitute latching means.

The screw insertion hole 7 on the chain case 1 side
And the mounting screw hole 18 of the mounting bracket 15 and the fixing screw (screw) 20 constitute screwing means. The rear end portion 2B of the case body 1 is attached to the rear end portion of the bicycle frame in the same manner as in the related art by using the mounting hole 6 and the rear mounting bracket 60 and a fixing screw (not shown). In the first embodiment, when the chain case 1 is mounted on the bicycle frame, first, the mounting bracket 15 is mounted on the boss portion of the crankshaft in the flow step and fixed before positioning the crank in the same manner as before in the conventional manner. In this case, the bicycle is transported in the upright state, and the mounting bracket 15 is mounted as it is. Therefore, the mounting bracket 17 is mounted so that the mounting piece 17 of the mounting bracket 15 is on the upper side (the lower side after assembly is completed).

In the next step, the bicycle crank is inserted through the insertion hole 5 of the case main body 2 so that the mounting screw insertion hole 7 of the front end 2A of the case main body 2 faces upward. Then, when the hook 19 of the mounting bracket 15 is inserted into the notch 9 of the hook recess 8 and the chain case 1 is rotated around the crankshaft, the hook 19 comes to fit in the recess 8. At the same time, the front projecting portion of the hooking piece is inserted into the recess 13 on the front side of the recess 8.

At this time, the vertical movement of the chain case 1 is prevented by the upper and lower walls 10A and 10B of the concave portion 8, and the front projecting portion of the hook piece 19 is inserted into the front concave portion 13 so that the left and right sides of the chain case are inserted. Movement in the direction is prevented. The hook piece 19 can move slightly back and forth in the recess 8. However, when the hook piece 19 moves rearward, the rear projection of the hook piece 19 is inserted into the recess 14 on the rear side of the recess 8. Therefore, the movement in the front-rear direction is substantially prevented. Therefore, by inserting the latching piece 19 into the latching recess 8, the front upper portion of the case body 2 is connected and fixed to the mounting bracket 15, and can be positioned at the regular mounting position.

When the front upper portion of the case body 2 is engaged with the latching piece 19 and the latching recess 8, the lower portion has
The mounting screw insertion hole 7 of the case body and the screw hole 18 of the mounting bracket 15 are substantially aligned, so that the fixing screw 20 can be easily inserted and screwed. Next, the mounting operation is completed by fixing the rear end portion 2B of the case main body 2 to the mounting bracket 60 with a fixing screw.

According to the first embodiment, the case body 2
On the front side of the bicycle, there is only one fixing point with screws.Moreover, in the flow process, the bicycle is transported in an upright position. Easy connection is possible by the locking means, and the screw fixing portion is on the upper side, so that screws can be easily inserted and tools can be easily used, so that screwing work can be easily performed.

In this embodiment, the case body 2
It is also possible to provide screwing means on the upper side and hooking means on the lower side (they are opposite sides when assembled). FIGS. 6 to 9 show a second embodiment of the present invention, in which a case body 2 has a front end 2A on the back side end of an edge flange 4 in a direction toward the center of the insertion hole 5 (a chain wheel). Locking flange 22 parallel to the front plate 3 projecting in the radial direction)
Is provided. The hook flange 22 is attached to the case body 2
Is a portion formed in an arc shape at the front end portion, and is formed vertically.

On the other hand, the mounting bracket 15 is substantially semicircular in a side view with the front end side formed in an arc shape, and is parallel to the edge flange 4 extending toward the front plate 3 of the chain case 1 around the arc portion. The locking projection 23 is provided, and the locking projection 23 is
It is formed over the upper and lower sides of the case body 2 corresponding to the hanging flange 22. Further, on the inner peripheral surface of the front end edge flange 4 of the case main body 2, as shown in FIG.
The stepped portion 24 is formed at a distance from the surface of the engaging flange 22 facing the front plate 3 that is equal to or slightly wider than the left and right width of the locking projection 23. That is,
The engaging flange 23 on one side of the mounting bracket 15 is inserted and engaged with the engaging flange 22, the edge flange 4, and the step portion 24 to form an engaging groove 25.

Therefore, when the locking projection 23 is inserted into the engagement groove 25, the edge of the locking projection 23 contacts the step 24 and is locked, and the left and right inner side surfaces of the mounting bracket 15 are The locking flange 22 is brought into contact with and locked by the locking flange 22, and the outer periphery of the locking projection 23 is
The case body 2 is brought into contact with the inner peripheral surface and locked.
Are supported so as not to move left and right and rearward with respect to the mounting bracket 15.

The lower thick portion 4A of the edge flange 4 provided below the front end 2A of the case body 2 is provided with a positioning recess 26 on the inner peripheral surface thereof. A positioning projection 27 that fits into the positioning recess 26 of the case body 2 protrudes from the end face. A fixed screw insertion hole 7 constituting a screwing means is provided from the bottom of the concave portion 26 to the outer periphery of the edge flange 4. And the convex part 2
At five portions, mounting screw holes 18 are provided.

Therefore, the case body 2 is positioned with respect to the mounting bracket 15 through the concave / convex fitting of the fitting portion 28 composed of the positioning concave portion 26 and the positioning convex portion 27, and the screw insertion hole 7 and the screw hole 18 are provided. Alignment of the position is ensured. In the second embodiment, the operation of attaching the chain case 1 is performed by inserting a bicycle crank through the insertion hole 5 of the case main body 2 and inserting the locking projection 23 of the mounting bracket 15 into the engagement groove of the case main body 2. 25. Then, the case main body 2 is rotated around the crankshaft in a state where the locking projections 23 are engaged with the engagement grooves 25, and the positioning concave portions 26 of the case main body 2 are fitted into the positioning convex portions 27 of the mounting bracket 15. Then, the case main body 2 is positioned with respect to the mounting bracket 15, and at this time, the screw holes 18 and the screw insertion holes 7 are formed.
And are aligned.

Then, the fixing screw 17 is screwed from the screw insertion hole 7 of the case main body 2 into the screw hole 15 of the mounting bracket 15, and the front part of the case main body 2 is fixed to the mounting bracket 15, and the rear part of the case main body 2 is fixed. The mounting operation is completed by screw fixing as in the first embodiment. According to the second embodiment, the positioning of the chain case 1 and the mounting bracket 15 is easy, and the case main body 2 is supported by engaging the mounting bracket 15 with the engaging groove of the case main body 2. Even if there is only one fixing screw 17, the front part of the case can be fixed.
In the flow process, the screwing operation can be performed on the bicycle in the upright state from the upper side, so that workability can be improved and the operation can be performed efficiently.

Further, since the engaging groove 25 and the locking projection 23 of the mounting bracket 15 are formed over the upper and lower sides of the case main body, the case main body 2 is reliably supported. In the present embodiment, the position where the fitting portion 28 is provided is not limited to the position where the screw hole 18 and the screw insertion hole 7 are formed, but may be formed in the vicinity of these holes or in the range of the engagement groove 25. Good. Further, the screwing means may be provided on the left and right side surfaces of the locking flange 22 of the case body 2 and the mounting fixture 15. The engagement groove 25 may be formed only on the upper side of the front end of the case body 2.

The first and second embodiments can be applied not only to a half-surface case as shown in FIG. 16 but also to a half-surface case in which a gear case is connected to the rear end. Further, the chain case 1 may be formed of a synthetic resin such as PP, polycarbonate, or the like in addition to the ABS.

[0031]

As described in detail above, according to the present invention,
The front side of the chain case is fixed by the hooking means and the screwing means, so that the number of screwing points can be reduced, and the connection between the case body and the mounting tool by the hooking means allows the case side to be fixed. Alignment of the screw holes with the mounting fixture side improves the mounting workability and work efficiency.

In addition, a latching piece constituting the latching means is provided at the upper end of the fixture, a latching recess is formed in the upper part of the case body, and a screw hole constituting the screwing means is formed at the lower end of the fixture. And the screw insertion hole is provided on the lower side of the case body, so that the upper part of the chain case (which is relatively difficult to assemble) with respect to the bicycle conveyed in the upright state when the chain case is assembled in the flow process. In the upright state, the lower side (the lower side) is easily engaged with the latching concave portion and the latching piece. Fastening with screws can be facilitated.

Further, the present invention makes it possible to reduce the number of screwed portions by engaging and supporting the mounting member in the engaging groove on the peripheral edge of the front portion of the case main body. By providing a fitting portion between the two, positioning of the case main body and positioning of the screw hole can be easily performed, thereby improving the mounting workability. When the above-described fitting portion is provided at the position where the screw hole and the screw insertion hole forming the screwing means are formed, the positioning by the fitting portion is performed at the screw fixing portion, and the screw hole and the screw insertion Alignment with the hole is ensured.

Further, when the engaging groove is formed at least on the upper side of the case main body and the screwing means is provided on the lower side of the case main body, when the chain case is mounted on a bicycle transported in the upright state. Can be easily screwed. Further, if the engaging groove is formed over the upper and lower portions of the front end of the case body, and the engaging portion of the attachment is formed corresponding to the engaging groove, the case body can be more reliably supported.

[Brief description of the drawings]

FIG. 1 is a rear view showing a first embodiment of the present invention.

FIG. 2 is a rear view of only the chain case of the embodiment.

FIG. 3 is a perspective view showing a mounting bracket of the embodiment.

FIG. 4 is an enlarged view of a portion A in FIG. 2;

FIG. 5 is a view taken along line BB of FIG. 4;

FIG. 6 is a partially omitted rear view showing a second embodiment of the present invention.

FIG. 7 is a rear view of only the chain case of the second embodiment.

FIG. 8 is a rear view showing the mounting bracket of the second embodiment.

FIG. 9 is a sectional view taken along line CC of FIG. 6;

FIG. 10 is a side view of a bicycle provided with a conventional chain case.

FIG. 11 is a perspective view showing a state in which a conventional case mounting bracket is mounted on a boss of a bicycle frame.

FIG. 12 is a perspective view showing a state where the mounting bracket of FIG. 11 is disassembled.

FIG. 13 is a rear view showing a conventional chain case.

FIG. 14 is a rear view showing a state where the chain case is mounted on a mounting bracket.

FIG. 15 is an enlarged cross-sectional view taken along line DD of FIG. 14;

FIG. 16 is a rear view showing another conventional example.

FIG. 17 is an enlarged cross-sectional view taken along line EE of FIG. 16;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Bicycle chain case 2 Case main body 7 Fixing screw insertion hole 8 Hook recess 15 Mounting fixture 18 Mounting screw hole 19 Hook piece 25 Engagement groove 28 Fitting part

Claims (8)

[Claims] A case body covering one side of a chain wheel and one side of a chain is provided, and a front side of the case body is attached via a fixture fixed to a boss of a crankshaft. A mounting means for connecting the case main body to the mounting tool by engaging the mounting tool and the case main body with each other and positioning the case main body at the mounting position. A mounting part for a bicycle chain case, comprising: a screwing means for fastening and fixing the mounting part to the mounting part. 2. The fixing device according to claim 1, wherein the latching means includes a latching piece provided at one end of the fixture, and a latching recess provided at a peripheral edge of the case body into which the latching piece fits. 2. The bicycle chain case according to claim 1, wherein the means has a screw hole provided at the other end of the attachment, and a screw insertion hole provided in the case body corresponding to the screw hole. Structure of mounting part. 3. A hooking piece is provided at an upper end of a fixture, and a hooking recess is formed at an upper portion of a case body.
The structure according to claim 2, wherein the screw hole is provided at a lower end of the attachment and the screw insertion hole is provided at a lower side of the case body. 4. A case body for covering one side of the chain wheel and one side of the chain, such that the front side of the case body is attached via a fixture fixed to a boss of a crankshaft. In the structure of the mounting portion of the bicycle chain case, at least one of the upper and lower sides of the periphery of the front portion of the case body,
An engagement groove for supporting the case body is provided in the attachment by engaging one side of the attachment, and the case body is positioned with respect to the attachment by the concave and convex fit between the attachment and the case body. The structure of the mounting portion of the bicycle chain case, wherein a fitting portion is provided, and screwing means for fastening and fixing the positioned case body and the mounting tool is provided on the upper and lower sides of the front portion of the case body. 5. The screwing means has a screw hole formed in a fixture and a screw insertion hole provided in a case body corresponding to the screw hole, and the fitting portion is provided with the screw hole and the screw hole. The structure of the mounting portion of the bicycle chain case according to claim 4, wherein the mounting portion is provided at a position where the screw insertion hole is formed. 6. The bicycle according to claim 4, wherein the engagement groove is provided at least on an upper side of the case body, and the screwing means is provided on a lower side of the case body. Structure of the mounting part of the chain case. 7. The engaging groove is formed over the front end of the case main body, and an engaging portion of the attachment is formed corresponding to the engaging groove.
Or the structure of the attachment part of the bicycle chain case of 6. 8. The structure according to claim 1, wherein said case body is made of a synthetic resin such as ABS, PP, or polycarbonate.