JP2013169957A - Chain case and electric bicycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a chain case that does not affect auxiliary sprockets and the like, even when external force acts from the vehicle body side in electric bicycles.SOLUTION: Between an auxiliary sprocket cover part 3 of a chain case 1 and an auxiliary drive unit 17 a spacing member 60 is arranged to maintain an interval between the chain case 1 and an auxiliary sprocket 21 at predetermined intervals.

Description

  The present invention relates to a bicycle chain case for covering a bicycle chain and a bicycle provided with the chain case.

  Bicycles are provided with chains that transmit the rotation of a crank with a pedal attached to drive wheels (mostly rear wheels). The chain is generally covered with a chain case to prevent the clothes of the passenger from coming into contact with the chain and becoming dirty.

  The chain case is often configured to cover not only the chain but also a pedal sprocket provided on the crankshaft and meshed with (engaged with) the chain.

  Furthermore, in an electric bicycle that assists a passenger's pedaling force with a driving force of an auxiliary driving unit (a driving device such as a motor and a unit including a speed reducer, an output shaft, an exterior case, and the like), for example, Patent Document 1 describes. As described above, the auxiliary sprocket for transmitting the driving force of the auxiliary driving unit to the chain may be configured to be covered by an auxiliary sprocket cover portion provided in the chain case.

JP 2000-335464 A

  However, the conventional chain case having an auxiliary sprocket cover is arranged so that the auxiliary sprocket cover covers the outside of the auxiliary sprocket, so that the passenger steps off the pedal and hits the chain case. The chain case will be displaced or deformed when an external force is applied from the side of the bicycle, such as when it has collapsed or it has been overturned due to a loss of balance, and the auxiliary sprocket cover will interfere with the auxiliary sprocket. As a result, the auxiliary sprocket and the cover may be damaged, and the chain may be detached from the auxiliary sprocket. Also, depending on the degree of displacement or deformation, the chain case may interfere with the pedal sprocket and the chain.

  In view of such problems, an object of the present invention is to provide a chain case that does not affect an auxiliary sprocket or the like even when an external force is applied from the side.

  The present invention provides a chain case that includes an auxiliary drive unit that applies auxiliary power to a chain, and that is attached to an electric bicycle in which an auxiliary sprocket that meshes with the chain is driven to rotate by the auxiliary drive unit. A main body cover portion that covers a portion, and an auxiliary sprocket cover portion that faces the side surface of the auxiliary drive unit and covers the outer side of the auxiliary sprocket, and between the auxiliary drive unit and the auxiliary sprocket cover portion The auxiliary sprocket can be mounted on the vehicle body so that it is located, and a spacing member that protrudes toward the auxiliary drive unit and maintains a predetermined distance between the auxiliary sprocket cover portion and the auxiliary sprocket is provided. It is characterized by.

In addition, the interval holding member is provided in the auxiliary sprocket cover portion.
Further, the auxiliary sprocket cover part is detachable from the main body cover part.

  Further, the auxiliary sprocket cover portion is provided with a first locking claw and a second locking claw, and a locking hole into which the second locking claw is inserted is formed in the main body cover portion. The one locking claw wraps inward from the edge of the main body cover portion, and is locked to the edge of the main body cover portion in the direction opposite to the direction in which the second locking claw is inserted into the locking hole. It is characterized by doing.

  The electric bicycle of the present invention is an electric bicycle that includes an auxiliary drive unit that imparts auxiliary power to the chain, an auxiliary sprocket that meshes with the chain is rotationally driven by the auxiliary drive unit, and has a chain case. The chain case has a main body cover portion that covers at least a part of the chain, and an auxiliary sprocket cover portion that faces the side surface of the auxiliary drive unit and covers an outer side of the auxiliary sprocket, and the auxiliary sprocket is An interval holding member is provided between the auxiliary drive unit and the auxiliary sprocket cover portion and maintains a predetermined interval between the auxiliary sprocket cover portion and the auxiliary sprocket.

  The chain case of the present invention is provided with an interval holding member that keeps the auxiliary sprocket cover part and the auxiliary sprocket at a predetermined interval. Therefore, when the passenger steps off the pedal and hits the chain case. Even when the balance is lost and the bicycle rolls over, the external sprocket cover is displaced or deformed due to external forces acting on the chain case. Since the distance between the auxiliary sprocket cover and the pedal sprocket can be prevented, the auxiliary sprocket cover can be prevented from interfering with the auxiliary sprocket or the pedal sprocket.

  Also, by making the auxiliary sprocket cover part detachable with respect to the main body cover part, if either the main body cover part or the auxiliary sprocket cover part is damaged, only the damaged member needs to be replaced, resulting in maintenance costs. Is reduced. Also, the main body cover part and the auxiliary sprocket cover part can be made of different materials, and it is easy to make the main body cover part and the auxiliary sprocket cover part have different colors without complicated painting work. It becomes possible.

  Further, the first locking claw of the auxiliary sprocket cover part turns inward from the edge of the main body cover part, the second locking claw is inserted into the locking hole of the main body cover part, and the first locking claw is The attachment state of the main body cover part and the auxiliary sprocket cover part by engaging with the edge part of the main body cover part in the direction opposite to the direction in which the second engaging claw is inserted into the engaging hole of the main body cover part Even if it receives an external force from the direction in which the second locking claw is inserted into the locking hole of the main body cover part or an external force from the opposite direction, it is in a stable attachment state that is not easily removed.

The side view which shows the electric bicycle provided with the chain case which concerns on an example of embodiment of this invention (The figure seen from the side with respect to the advancing direction of a bicycle) 1 is a cross-sectional view taken along line AA in FIG. The perspective view which shows the pedal sprocket vicinity area | region of the electric bicycle in the same embodiment 1 is a cross-sectional view taken along the line B-B in FIG. It is a figure which shows the chain case in the embodiment, the viewpoint of FIG. 1 is made into the front, (a) is a left view, (b) is a front view, (c) is a bottom view, (d) is a rear view. The perspective view which shows the chain case in the embodiment The perspective view which shows the attachment structure of the main body cover part and auxiliary sprocket cover part of the chain case in the embodiment It is a figure which shows the latching location of the main body cover part and auxiliary | assistant sprocket cover part in the embodiment, (a) is CC sectional view taken on the line of FIG.5 (d), (b) is FIG.5 (d). ) D-D cross-sectional view Sectional drawing which shows the pedal sprocket vicinity area | region of the electric bicycle in another embodiment

Hereinafter, a chain case according to an example of an embodiment of the present invention and an electric bicycle including the chain case will be described with reference to the drawings.
FIG. 1 is a side view of an electric bicycle 10 including a chain case 1 as an example of an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line AA in FIG. 1 (so that the inside of the chain case 1 can be seen. 3 shows a state in which the crank 15 is removed and the lower part of the chain case 1 is partially broken. FIG. 3 is a perspective view of the vicinity of the pedal sprocket 20 (the state in which the chain case 1 is removed so that the structure can be easily seen). 4 is a sectional view taken along the line BB in FIG. 1 in the vicinity of the pedal sprocket 20, FIG. 5 and FIG. 6 show the chain case 1, and FIG. 7 shows the main body cover portion 2 of the chain case 1. The attachment structure with the auxiliary sprocket cover 3 is shown in FIG. 8, a cross-sectional view of the locking portion between the main body cover 2 and the auxiliary sprocket cover 3 is shown in FIG. 9, and the vicinity of the pedal sprocket 20 in another embodiment is shown in FIG. Cross section Show.

  The electric bicycle 10 in FIG. 1 includes a vehicle body frame 11, front wheels 12 and rear wheels 13, a handle 14, a crank 15 (crankshaft 15a) and a pedal 16, and a driving device that generates auxiliary driving force (assist force). As an auxiliary drive unit 17 having an electric motor (not shown) as a battery, a battery 18 composed of a secondary battery that supplies driving power to the electric motor, and a pedaling force (manpower driving force) from the pedal 16 on the rear wheels 13, a chain 19 and the like for transmission to 13 are provided.

  1, 2 and 3, the vehicle body frame 11 includes a head pipe 11a, a front fork 11b, a main pipe 11c, a support bracket 11d for supporting the auxiliary drive unit 17, a standing pipe 11e, a chain. It is composed of a stay 11f, a seat stay 11h, and the like.

  In the vehicle body frame 11, the rear end portion of the main pipe 11c, the lower end portion of the standing pipe 11e, and the front end portion of the chain stay 11f are connected by a support bracket 11d or the like, and are in an attitude of hanging from the support bracket 11d. A unit 17 is attached.

  As shown in FIGS. 3 and 4, a pedal sprocket (also referred to as a front gear or a front sprocket) that is attached to the right side surface of the auxiliary drive unit 17 so as to rotate integrally with the crankshaft 15a. ) 20 is provided. As shown in FIG. 4, the auxiliary drive unit 17 includes a motor 17a, an output shaft 17b, a reduction gear 17c as a speed reducer that reduces the rotation of the motor 17a and transmits it to the output shaft 17b, a motor 17a, It has an outer case 17d for housing the gear 17c.

  Further, the rear side of the right side surface of the auxiliary drive unit 17 is attached to the auxiliary sprocket 21 that is attached so as to rotate integrally with the output shaft 17b of the auxiliary drive unit 17 and outputs an auxiliary drive force, or to the chain 19. An idler gear (also referred to as idler sprocket) 22 for applying a constant tension is assembled.

As shown in FIG. 1, a small-diameter wheel gear (also referred to as a rear gear or a rear sprocket) 23 is attached to the hub of the rear wheel 13.
The chain 19 is stretched over the pedal sprocket 20, the auxiliary sprocket 21, the idler gear 22, and the wheel gear 23, and the pedaling force (human power driving force) applied to the pedal is transmitted to the chain 19 through the pedal sprocket 20. At the same time, the auxiliary driving force from the auxiliary sprocket 21 is transmitted to the chain 19, and the resultant force of these pedaling force and auxiliary driving force is transmitted to the wheel gear 23 via the chain 19, whereby the rear wheel 13 is rotationally driven. It is comprised so that.

  As shown in FIGS. 5 and 6, the chain case 1 of the present embodiment has a main body cover portion 2 and an auxiliary sprocket cover portion 3. The outer peripheral edge of the main body cover portion 2 is an edge bent toward the inner side (the body frame 11 side is the inner side), of which the front outer peripheral edge (the bicycle traveling direction side is the front side) Two elongated holes 2b through which the fixing screws 26 for the bicycle body are inserted are formed, and a round hole 2c through which the bicycle crank is passed is formed in the front center portion of the body cover portion 2. The round hole 2c is configured by attaching an annular rim member 2d made of synthetic resin to an opening formed in the main body cover portion 2.

  As shown in FIGS. 1 and 4, the chain case 1 is disposed adjacent to the right side of the pedal sprocket 20 so as to cover a part of the chain 19. The body cover portion 2 of the chain case 1 covers the pedal sprocket 20, the meshing portion of the chain 19 and the pedal sprocket 20, and the upper portion of the region extending rearward of the chain 19. The auxiliary sprocket cover 3 covers the outer side of the auxiliary sprocket 21.

  Here, as shown in FIG. 4, the auxiliary sprocket 21 is positioned between the auxiliary sprocket cover 3 and the outer case 17 d of the auxiliary drive unit 17 in a state where the chain case 1 is mounted.

  As shown in FIGS. 2 and 4, a spacing member 60 is provided between the auxiliary sprocket cover 3 and the auxiliary drive unit 17. The spacing holding member 60 maintains a distance L1 between the flat portion 30 of the auxiliary sprocket cover portion 3 and the outer case 17d of the auxiliary drive unit 17 so that the space between the flat portion 30 of the auxiliary sprocket cover portion 3 and the auxiliary sprocket 21 is maintained. Is maintained at a predetermined interval L2.

  In the present embodiment, the spacing member 60 protrudes toward the auxiliary drive unit 17 in a state where the chain case 1 is attached to the vehicle body frame 11, and its tip end (end on the side of the auxiliary drive unit 17) is auxiliary. The auxiliary sprocket cover 3 is provided at the lower end of the auxiliary sprocket cover 3 so as to be in contact with the surface of the outer case 17 d of the drive unit 17.

Further, as shown in FIG. 7, the auxiliary sprocket cover portion 3 is detachable from the main body cover portion 2 in the present embodiment.
The auxiliary sprocket cover portion 3 in the present embodiment is made of synthetic resin and has a flat portion 30 having a flat surface as shown in FIGS. The flat portion 30 includes a substantially L-shaped first edge 32 bent in the vehicle body inner direction (vehicle body frame 11 side) from the lower front end to the rear upper end of the auxiliary sprocket cover portion 3, and the first edge portion 32. The front and rear ends are surrounded by a second edge 34 that connects in a curved manner.

  As shown in FIGS. 6, 7, and 8, the main body cover portion is provided at the connection portion (the front and rear end portions of the auxiliary sprocket cover portion 3) between the first edge portion 32 and the second edge portion 34. 2 is provided with a U-shaped first locking claw 32a that can be wrapped inside from the edge of 2 to the inside (body frame 11 side) and wrap around the thickness dimension of the body cover portion 2, A plurality of (here, three) second locking claws 34 a are provided between the first locking claws 32 a of the second edge portion 34. The second locking claw 34 a protrudes inward from the flat portion 30 and has a shape protruding forward from the second edge portion 34.

  The flat portion 30 is provided with a plurality (two in this case) of joining pieces 30a. Here, the spacing member 60 is integrated with the auxiliary sprocket cover portion 3 so as to protrude with respect to the flat portion 30 near the first locking claw 32a (front side) at the first edge portion 32. Is provided.

  The first locking claw 32a and the second locking claw 34a are formed integrally with the flat portion 30 so as to protrude in the same direction (the vehicle body frame 11 side) as the spacing member 60. The protruding amount is smaller than that of the spacing member 60.

  On the other hand, the main body cover portion 2 is provided with an attachment surface 31 for attaching the auxiliary sprocket cover portion 3 behind the round hole 2c through which the crank 15 passes. The attachment surface 31 is provided with a joining portion 30b for joining the joining piece 30a of the auxiliary sprocket cover portion 3 on the flat surface, and the auxiliary sprocket cover portion 3 has an auxiliary sprocket cover at the front edge thereof. A locking hole 34b for passing the second locking claw 34a of the portion 3 is provided.

  When attaching the auxiliary sprocket cover part 3 to the main body cover part 2, the first locking claw 32a is turned inside the main body cover part 2 while slightly bending the whole auxiliary sprocket cover part 3, The two locking claws 34a are inserted into the locking holes 34b in the direction of the arrow X (insertion direction) shown in FIGS. 5 (d) and 8 (b).

  Then, as shown in FIG. 8A, the first locking claw 32a locks from the inner side to the outer side so as to wrap around the thickness of the edge of the main body cover 2, and FIG. 8), the first locking claw 32a is engaged in the direction of the arrow Y shown in FIG. 8A (the direction opposite to the direction of the arrow X and corresponding to the direction in which the second locking claw 34a is detached). Stop. And as shown in FIG.8 (b), the 2nd latching claw 34a will also be in the state latched inside the main body cover part 2 through the latching hole 34b.

Thereby, the auxiliary sprocket cover 3 is attached to the main body cover 2.
Further, the joining piece 30a of the auxiliary sprocket cover part 3 and the joining part 30b of the body part 2 are joined by screwing with screws 30c as shown in FIG. The auxiliary sprocket cover 3 is fixed to each other.

  In this way, the auxiliary sprocket cover portion 3 is overlapped on the attachment surface 31 of the main body cover portion 2 from the outside (front side), and the first engagement of the auxiliary sprocket cover portion 3 as shown in FIGS. By locking the pawl 32a and the second locking pawl 34a to the inner side (back side) of the main body cover portion 2, the attachment state of the main body cover portion 2 and the auxiliary sprocket cover portion 3 can be viewed from the front side or the back side. Since it is locked and is locked from both the directions of arrows X and Y in FIGS. 5 (d), 8 (a), and 8 (b), it can be subjected to external force from any direction. It becomes a stable mounting state that cannot be easily removed.

  Further, if the mounting surface 31 has a structure that extends integrally from the main body cover portion 2 and reaches the front of the first edge 32 of the auxiliary sprocket cover portion 3, the region covered by the auxiliary sprocket cover portion 3 is the main body cover. A double structure is formed by superimposing the attachment surface 31 of the part 2 and the auxiliary sprocket cover part 3, and a stronger structure is obtained.

  And if it is such an attachment structure, since the main body cover part 2 and the auxiliary sprocket cover part 3 can be comprised with another material (for example, a metal and a synthetic resin), even if it does not perform a complicated painting operation, The main body cover portion 2 and the auxiliary sprocket cover portion 3 can be easily made different colors.

The above is the structure of the chain case 1 in this embodiment.
Next, a structure for attaching the chain case 1 to the vehicle body frame 11 will be described. In the support bracket 11d for supporting the auxiliary drive unit 17 shown in FIG. 3, as described above, the rear end portion of the main pipe 11c, the lower end portion of the standing pipe 11e, and the front end portion of the chain stay 11f in the vehicle body frame 11. In addition to this, the front portion of the chain case 1 is attached and fixed to the vehicle body frame 11 via the front cover metal fitting 25.

  As shown in FIG. 4, the front cover metal fitting 25 has a bolt hole 25 a through which the bolt 28 is inserted, and a screw hole 25 b to which the fixing screw 26 is attached. As shown in FIGS. 2, 3, and 4, the front cover metal fitting 25 is fixed to the vehicle body frame 11 (such as the support bracket 11d) by fixing bolts 28 inserted into the plurality of bolt holes 25a. The fixing screws 26 are respectively screwed into the screw holes 25 b through the long holes 2 b of the chain case 1, whereby the front portion of the chain case 1 is fixed to the vehicle body frame 11 via the cover front bracket 25.

  As shown by a broken line in FIG. 1, an attachment piece portion 11 g that protrudes upward and attaches the rear end portion of the chain case 1 is formed in the vicinity of the rear end portion of the chain stay 11 f. As shown in FIGS. 5 and 6, a long hole 5 is formed at the rear end of the chain case 1. As described above, after the front portion of the chain case 1 is attached to the support bracket 11d of the vehicle body frame 11 via the front cover metal fitting 25, the rear end portion of the chain case 1 is attached to the attachment piece portion of the chain stay 11f. The rear end portion of the chain case 1 is fixed to the vehicle body frame 11 by being brought into contact with 11g and screwing the locking screw 29 through the elongated hole 5 of the chain case 1 into the screw hole formed in the attachment piece portion 11g. .

The above is the structure of the battery-assisted bicycle 10 and the chain case 1 provided in the battery-assisted bicycle 10 and the mounting structure thereof.
Next, a state when an external force is applied from the outside of the auxiliary sprocket cover portion 3 of the chain case 1 will be described.

  When an external force F is applied from the outer side of the auxiliary sprocket cover 3 (right side in FIG. 4), the auxiliary sprocket cover 3 is directed toward the inner side (body frame 11 side) where the auxiliary sprocket 21 and the pedal sprocket 20 are arranged. The auxiliary sprocket cover part 3 tends to be displaced inward.

  However, since the tip of the spacing member 60 provided on the auxiliary sprocket cover 3 is in contact with the surface of the exterior case 17d of the auxiliary drive unit 17, the force that presses the auxiliary sprocket cover 3 is the spacing member 60. The auxiliary sprocket cover part 3 cannot be displaced inward by being blocked by the outer case 17d. For this reason, even if the external force F is applied, the distance L1 between the flat portion 30 of the auxiliary sprocket cover 3 and the auxiliary drive unit 17 is maintained at about the length L0 of the distance holding member 60. Therefore, the interval L2 between the flat portion 30 of the auxiliary sprocket cover 3 and the auxiliary sprocket 21 is also maintained at a predetermined interval such that the sprocket cover 1b does not contact the auxiliary sprocket 21.

  In the above embodiment, the tip of the spacing member 60 is brought into contact with the surface of the exterior case 17d of the auxiliary drive unit 17, but as another embodiment, as shown in FIG. A slight gap may be provided between the front end portion and the outer case 17d. Specifically, the distance L3 between the front end portion of the distance holding member 60 and the outer case 17d may be an interval that is shorter than the distance L2 between the flat portion 30 and the auxiliary sprocket 21 (L2> L3).

  In this case, the tip of the spacing member 60 contacts the surface of the auxiliary drive unit 17 before the flat portion 30 of the auxiliary sprocket cover 3 reaches the auxiliary sprocket 21 due to deformation or displacement due to the external force F.

  As a result, the auxiliary sprocket cover portion 3 cannot be displaced further inward, and the amount of displacement of the flat portion 30 of the auxiliary sprocket cover portion 3 in this case is kept at the interval L3. Therefore, the interval between the auxiliary sprocket cover 3 and the auxiliary sprocket 21 after the external force F is applied (that is, the interval L2 to the interval L3) is kept at a predetermined interval so that the auxiliary sprocket cover 3 does not contact the auxiliary sprocket 21. (L2-L3> 0).

  In the above-described embodiment, the spacing member 60 is provided at the lower end of the auxiliary sprocket cover 3 of the chain case 1. However, the spacing member 60 is positioned at the chain case 1 by an external force from the outside. Any position can be used as long as the distance between the chain case 1 and the auxiliary sprocket 21 can be kept at a predetermined distance by maintaining the distance between the chain case 1 and the outer case 17d when the inner side is pressed inward. You may provide in the upper end part of the part 3, and a center part.

  Further, the interval holding member 60 may be provided not on the chain case 1 side but on the auxiliary drive unit 17 side, and for example, a protrusion protruding from the outer case 17d may be provided. Alternatively, the spacing member 60 may be separated from the chain case 1 and the auxiliary drive unit 17 so that a block-like structure is sandwiched between the chain case 1 and the auxiliary drive unit 17.

  The present invention can be applied not only to the electric bicycle and its chain case that assist the passenger's pedaling force with the driving force of the auxiliary driving unit, but also to run with only the driving force of the driving unit in a state where the pedaling force does not act. It can also be applied to bicycles.

DESCRIPTION OF SYMBOLS 1 Chain case 2 Main body cover part 3 Auxiliary sprocket cover part 10 Electric bicycle 11 Body frame 17 Auxiliary drive unit 15 Crank 19 Chain 20 Pedal sprocket 21 Auxiliary sprocket 60 Spacing holding member

Claims (6)

In a chain case provided with an auxiliary drive unit for applying auxiliary power to the chain, and attached to an electric bicycle in which an auxiliary sprocket meshing with the chain is driven to rotate by the auxiliary drive unit,
A main body cover portion covering at least a part of the chain;
An auxiliary sprocket cover portion that covers the outer side of the auxiliary sprocket facing the side surface of the auxiliary drive unit,
The auxiliary sprocket can be mounted on the vehicle body so that the auxiliary sprocket is positioned between the auxiliary drive unit and the auxiliary sprocket cover.
A chain case, characterized in that an interval holding member is provided that protrudes toward the auxiliary drive unit and keeps a distance between the auxiliary sprocket cover portion and the auxiliary sprocket at a predetermined interval or more.   The chain case according to claim 1, wherein the spacing member is provided on the auxiliary sprocket cover portion.   The chain case according to claim 1 or 2, wherein the auxiliary sprocket cover part is detachable from the main body cover part. The auxiliary sprocket cover part is provided with a first locking claw and a second locking claw,
A locking hole into which the second locking claw is inserted is formed in the main body cover portion,
The first locking claw wraps inward from the edge of the main body cover portion, and the edge of the main body cover portion is opposite to the direction in which the second locking claw is inserted into the locking hole. The chain case according to claim 3, wherein the chain case is locked.   An electric bicycle comprising the chain case according to any one of claims 1 to 4. An auxiliary drive unit that applies auxiliary power to the chain is provided, and an auxiliary sprocket that meshes with the chain is driven to rotate by the auxiliary drive unit, and has an chain.
The chain case is
A main body cover portion covering at least a part of the chain;
An auxiliary sprocket cover portion that covers the outer side of the auxiliary sprocket facing the side surface of the auxiliary drive unit,
The auxiliary sprocket is located between the auxiliary drive unit and the auxiliary sprocket cover,
An electric bicycle characterized in that an interval holding member is provided to maintain a distance between the auxiliary sprocket cover portion and the auxiliary sprocket at a predetermined interval or more.

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