JP2009208622A - Swing arm structure for motorcycle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a swing arm structure for a motorcycle, receiving an axial force of an axle while reducing cost and weight and improving an assemblability of the axle. <P>SOLUTION: The motorcycle comprises: a swing arm 24 drilled with a long hole 85a inserting the axle 57; an end cap 91 sealing a rear end opening of the swing arm 24; an adjust bolt 92 penetrating through the end cap 91; a washer part 93 attached to a front end of the adjust bolt 92 and drilled with an axle insertion hole for passing the axle 57 therethrough, a drive chain; and a chain adjuster 63 adjusting the tension of the drive chain. A reinforcing plate 101 arranged vertically apart along upper and lower sides 85b, 85c of the long hole 85a across the axle 57 is attached to the end cap 91, and the axis force of the axle 57 is received by the reinforcing plate 101 by arranging the reinforcing plate 101 in the swing arm 24 by attaching the end cap 91 to the swing arm 24. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an improvement in a swing arm structure for a motorcycle.

As a conventional motorcycle swing arm structure, a structure in which a swing arm is formed of an extruded material is known (for example, see Patent Document 1).
JP 63-166680 A

1 and 2 of Patent Document 1 will be described below.
The rear arm 1 as a swing arm includes a pair of left and right arm members 2a, 2b, and these arm members 2a, 2b are made of extruded material, and are between an upper wall 11, a bottom wall 12, side walls 13, 14, and side walls 13, 14. The partition walls 15 and 16 delivered to are members formed integrally.

  The side walls 13 and 14 are respectively formed with long through holes 18 extending laterally, and the axle shaft 17 is passed through these through holes 18 and 18. The axle 17 is also passed through a chain tensioner 19 that adjusts the tension of the drive chain.

  When an axial force is applied to the axle 17 when the axle 17 is assembled to the rear arm 1, this axial force is mainly received by the partition walls 15 and 16 of the arm members 2a and 2b.

  In order to mold the arm members 2a and 2b made of the extruded material, dedicated equipment is required, which increases the cost. Moreover, since the partition walls 15 and 16 are continuously formed from one end to the other end of the arm members 2a and 2b, the weight of the arm members 2a and 2b is larger than a simple rectangular cross section. Furthermore, it is desirable that the axle 17 can be easily assembled when the axle 17 is assembled to the rear arm 1.

  An object of the present invention is to provide a swing arm structure for a motorcycle that can receive the axial force of an axle while reducing the cost and weight and improving the assembly of the axle.

  The invention according to claim 1 is a swing arm that is attached to a vehicle body or an engine so as to be swingable up and down, and has a long hole through which a rear wheel axle is passed at a rear end portion, and an end cap that closes the rear end opening of the swing arm. An adjustment screw arranged to pass through the end cap, a washer attached to the front end of the adjustment screw and having a through hole through which the axle penetrates, and transmits the driving force on the engine side to the rear wheel In a motorcycle equipped with a drive chain and a chain adjuster that adjusts the tension of the drive chain by adjusting the position of the axle in the front-rear direction, the end cap is vertically moved along the upper and lower sides of the slot with the axle in between. Reinforcement plates placed apart from each other are attached, and the end plate is attached to the swing arm to attach the reinforcement plate. Disposed within Guamu, characterized in that for receiving the axial force of the axle with the reinforcing plate.

As an action, the reinforcing plate is disposed between the left and right side walls in the swing arm, and receives an axial force when the axle is assembled by the reinforcing plate.
Since the reinforcing plate is arranged so as to be vertically separated along the upper and lower sides of the long hole across the axle, the rear wheel axle is guided by the reinforcing plate when the rear wheel axle is passed through the long hole. The wheel axle is easy to insert into the slot. Further, since the reinforcing plate is supported by an end cap that closes the rear end opening of the swing arm, a member or a process that specifically supports the reinforcing plate is not required.

The invention according to claim 2 is characterized in that the front end of the reinforcing plate is formed in a U shape in a side view.
As a function, it is possible to form a single member along the upper and lower sides of the slot so that they can be separated from each other, so that the accuracy of the vertical spacing of the reinforcing plate is increased, the number of parts is reduced, and cost increases are suppressed. It is done.

  In the invention according to claim 1, a reinforcing plate is attached to the end cap so as to be vertically separated along the upper and lower sides of the elongated hole across the axle, and the reinforcing plate is attached by attaching the end cap to the swing arm. Is placed in the swing arm and receives the axial force of the axle with the reinforcing plate, so it can be inserted into the long hole while guiding the axle with the reinforcing plate when installing the axle, improving the axle assembly The arm portion of the swing arm can withstand the axial force, and the reinforcing plate can be supported by the existing end cap, eliminating the need for a special support member or processing for the reinforcing plate. Thus, cost and weight can be reduced.

  In the invention according to claim 2, since the front end of the reinforcing plate is formed in a U shape in a side view, the accuracy of the vertical distance of the reinforcing plate can be improved, and the axial force is always applied at a position close to the axle. Can receive. Further, since only one member is required, the number of parts can be reduced, and the cost of the reinforcing plate can be reduced.

The best mode for carrying out the present invention will be described below with reference to the accompanying drawings. The drawings are viewed in the direction of the reference numerals.
FIG. 1 is a side view of a motorcycle provided with a swing arm reinforcement structure according to the present invention. A motorcycle 10 includes a body frame 11 serving as a skeleton, a head pipe 12 provided at a front end, and a head pipe 12. A main frame 13 extending rearward and obliquely downward, a pivot plate 14 attached to the rear end of the main frame 13, and a pair of left and right seat rails 16 and 17 extending forward and obliquely upward from the middle of the main frame 13 (reference numerals on the front side) 16), and a pair of left and right subframes 18 and 19 (only the reference numeral 18 on the front side is shown) connecting the rear end of the main frame 13 and the seat rails 16 and 17, respectively. A front fork 21 is steerably attached to the main frame 13 and the pivot plate 14. 2 is attached, swingably swing arm 24 is mounted via a pivot shaft 23 to the pivot plate 14, the fuel tank 26 is attached to the seat rails 16, 17.

The front fork 21 has a bar handle 32 attached to a steering stem 31 constituting an upper portion thereof, and a front wheel 33 attached to a lower end thereof.
The engine 22 has a transmission 34 integrally provided at a rear portion thereof and is long and substantially horizontally disposed in the front and rear, a cylinder block 37 is attached to a crankcase 36, and a drive source in which a cylinder head 38 is attached to the cylinder block 37. It is.
An intake device 41 is attached to the upper portion of the cylinder head 38, and an exhaust device 42 is attached to the lower portion of the cylinder head 38.

The intake device 41 includes a carburetor 46 connected to the cylinder head 38 via an intake pipe 44 and an air cleaner 47 connected to the carburetor 46 via a connecting tube (not shown).
The exhaust device 42 includes an exhaust pipe 51 attached to the cylinder head 38 and a muffler 52 connected to the rear end of the exhaust pipe 51.

In the transmission 34, an output shaft 54 projects laterally from the side surface of the crankcase 36, and a drive sprocket 56 is attached to the output shaft 54.
The swing arm 24 includes a pair of left and right arm portions 55, 55 (only the front side reference numeral 55 is shown), and an axle 57 is passed to the rear ends of these arm portions 55, 55. A ring 58 is attached.

  A driven sprocket 61 is integrally provided on the rear wheel 58, a drive chain 62 is hung on the drive sprocket 56 and the driven sprocket 61, and a chain for adjusting the tension of the drive chain 62 at the rear end of the swing arm 24. An adjuster 63 is provided.

  Rear cushion units 67 and 67 (only front side reference numeral 67 are shown) on the rear end of the swing arm 24 and brackets 64 and 66 (only front side reference numeral 64 shown) provided on the seat rails 16 and 17, respectively. ) Delivered and installed.

  Here, reference numeral 71 is a handle cover, 72 is a front cover, 73 is a front fender, 74 is a leg shield, 76 is a seat, 77 is a body cover, 78 is a tail lamp, 81 is a rear fender, and 82 is a main stand.

  FIG. 2 is a rear plan view of the motorcycle according to the present invention (a partial cross-sectional view, where an arrow (FRONT) in the drawing represents the front of the motorcycle), and left and right arm portions of the swing arm 24. A bolt-shaped axle 57 is passed through 55 and 55, and a rear wheel 58 is rotatably attached to the axle 57.

  The arm portion 55 of the swing arm 24 has a rectangular cross-sectional shape, and is formed on the outer side of the arm portion 55, that is, on the side of the outer wall 85 of the outer wall 85 and the inner wall 86 of the arm portion 55. A chain adjuster 63 that adjusts the front-rear position is disposed. Reference numeral 87 denotes a nut screwed to the tip of the axle 57.

  The chain adjuster 63 includes an adjustment bolt 92 that passes through an end cap 91 provided at the rear end of the arm portion 55, a washer portion 93 that is attached to the tip of the adjustment bolt 92 so as to extend in the front-rear direction, and an adjustment bolt 92. The two nuts screwed to the rear of the end cap 91, that is, an adjustment nut 96 and a lock nut 97 for locking the adjustment nut 96 are included.

FIG. 3 is a cross-sectional view of the rear end portion of the swing arm according to the present invention, and shows a cross section along the axle 57.
The end cap 91 is a member in which a reinforcing plate 101 having a width equal to or smaller than the interval K1 between the outer wall 85 and the inner wall 86 is attached to the inner surface 91a facing the arm member 55.
The end cap 91 and the reinforcing plate 101 are parts constituting the end cap assembly 102.

  Such a reinforcing plate 101 is provided to suppress deformation of the arm member 55 so that the arm member 55 can withstand the axial force when the axle 57 is assembled to the swing arm 24 and tightened by applying an axial force. Because.

  Further, the end cap 91 is provided with a side protrusion 91b that protrudes outward from the arm member 55, and a bolt insertion groove 91c into which the adjustment bolt 92 is inserted is formed in the side protrusion 91b. .

  Thus, even if the chain adjuster 63 is provided on the outer side of the arm member 55 of the end cap 91, the end plate 91 is not fixed to the arm member 55 because the reinforcing plate 101 is inserted into the arm member 55. However, the end cap 91 can be prevented from tilting.

  The adjustment bolt 92 has a flat portion 92a at the tip, and an outer surface 93a of a washer portion 93 is attached to the flat portion 92a by welding. 85a and 86a are long holes in the front and rear of the outer wall 85 and the inner wall 86 of the arm portion 55 for passing the axle 57, and 93b is opened in the washer portion 93 for passing the axle 57. Axle insertion hole.

FIG. 4 is a side view of the rear end portion of the swing arm according to the present invention, and the washer portion 93 has an arcuate shape that spreads upward and downward from the rear edge 93e where the upper edge 93c and the lower edge 93d extend vertically. It is a member having an outer shape connected to the front edge 93f, and covers and conceals a long hole 85a formed in the outer wall 85 of the arm member 55.
The distance between the upper wall 107 and the bottom wall 108 of the arm part 55 is set to K2.

  FIG. 5 is a perspective view showing an end cap assembly according to the present invention. The end cap assembly 102 includes an end cap 91 and a laterally U-shaped reinforcing plate 101 attached to the end cap 91.

The end cap 91 is a member in which a bolt insertion groove 91c into which an adjustment bolt 92 (see FIG. 4) is inserted is formed in the side protrusion 91b.
The reinforcing plate 101 is a member having a simple shape obtained by bending a flat plate, and can be manufactured at a low cost.

  FIG. 6 is a side view of the end cap assembly according to the present invention. The end cap 91 has a protruding surface 91d formed on the inner surface 91a by press molding, and the reinforcing plate 101 is attached to the protruding surface 91d by welding. Yes. In addition, 91f is a recessed part formed when the outer surface 91g was compressed when forming the protrusion surface 91b.

The edge of the protruding surface 91d is a portion for positioning the end cap 91 with respect to the arm member 55 when the end cap 91 is applied to the end of the arm member 55 (see FIG. 4).
The reinforcing plate 101 includes upper and lower flat plate portions 101a and 101a and an arcuate plate portion 101b that integrally connects the end portions of the flat plate portions 101a and 101a.

If the interval between the flat plate portions 101a and 101a is K3, for example, when a reinforcing plate made of two flat plates is welded to the end cap 91 and the interval between these flat plates is set to K3, each flat plate is an end cap. Since the distance K3 may change because it is fixed in a cantilever shape to 91, in contrast to this, in the reinforcing plate 101 of the present invention, both ends of the flat plate portions 101a and 101a are connected together. Therefore, the interval K3 can always be kept constant, and the axial force can be stably received at a position closer to the axle 57.
When the outer diameter of the axle 57 is D, the distance K3 is equal to or slightly larger than the outer diameter D.

  Returning to FIG. 4, the long hole 85 a includes a parallel upper side 85 b and a lower side 85 c, and the flat plate portions 101 a and 101 a of the reinforcing plate 101 extend along the upper side 85 b and the lower side 85 c of the long hole 85 a across the axle 57. Are arranged apart from each other.

FIG. 7 is a view taken in the direction of arrow 7 in FIG. 6. The width W1 of the reinforcing plate 101 and the lateral width W2 of the projecting surface 91d formed on the inner surface 91a of the end cap 91 are the outer side of the arm member 55 shown in FIG. The distance K1 between the wall 85 and the inner wall 86 is equal to or slightly smaller than the distance K1.
Further, the vertical width W3 of the protruding surface 91d is equal to or slightly smaller than the interval K2 between the upper wall 107 and the bottom wall 108 of the arm member 55 shown in FIG.

  As shown in FIGS. 1, 4, and 6, the vehicle body frame 11 (specifically, the pivot plate 14) or the engine 22 is mounted so as to swing up and down, and an axle 57 for the rear wheel 58 is provided at the rear end. The swing arm 24 in which elongated holes 85a and 86a are passed, an end cap 91 that closes the rear end opening of the swing arm 24, and an adjustment bolt 92 that is an adjustment screw that is disposed so as to pass through the end cap 91. A washer portion 93 attached to the front end of the adjustment bolt 92 and having an axle insertion hole 93b as a through hole through which the axle 57 passes, a drive chain 62 for transmitting the driving force on the engine 22 side to the rear wheel 58, Chain adjuster that adjusts the tension of the drive chain 62 by adjusting the position of the axle 57 in the front-rear direction 63, the reinforcing plate 101 is attached to the end cap 91 so as to be separated from the upper and lower sides along the upper and lower sides 85b and 85c of the long holes 85a and 86a with the axle 57 interposed therebetween. By attaching the end cap 91 to the swing arm 24, the reinforcing plate 101 is disposed in the swing arm 24 and receives the axial force of the axle 57 by the reinforcing plate 101. Can be inserted into the elongated holes 85a and 86a, the assemblability of the axle 57 can be improved, and the arm portions 55 and 55 of the swing arm 24 can withstand the axial force. The reinforcing plate 101 can be supported by the existing end cap 91, and no special support member or processing for the reinforcing plate 101 is required. It is possible to reduce the strike and weight.

  Further, as shown in FIGS. 5 and 6, the reinforcing plate 101 has a front end formed in a U shape in a side view, so that the accuracy of the vertical interval K3 of the reinforcing plate 101 can be improved. An axial force can always be received at a position close to the axle 57. Further, since only one member is required, the number of parts can be reduced, and the cost of the reinforcing plate 101 can be reduced.

  In this embodiment, as shown in FIG. 6, the reinforcing plate 101 has a U-shaped sideways shape. However, the present invention is not limited to this, and the U-shaped sideways shape may be used. In short, the left ends of the upper and lower flat plate portions 101 a and 101 a are Any shape that connects together may be used.

  Further, as shown in FIG. 1, the swing arm 24 is swingably attached to the pivot plate 14 constituting the vehicle body frame 11. However, the swing arm 24 is not limited to this, and the swing arm 24 is swung to the rear portion of the engine 22, that is, the rear portion of the crankcase 36. The swing arm 24 may be attached freely.

  The swing arm reinforcing structure of the present invention is suitable for a motorcycle.

1 is a side view of a motorcycle including a swing arm reinforcement structure according to the present invention. Fig. 2 is a rear plan view of the motorcycle according to the present invention. It is sectional drawing of the swing arm rear-end part which concerns on this invention. It is a side view of the rear-end part of the swing arm which concerns on this invention. It is a perspective view which shows the end cap assembly which concerns on this invention. It is a side view of the end cap assembly which concerns on this invention. FIG. 7 is a view taken in the direction of arrow 7 in FIG. 6.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Motorcycle, 11 ... Car body (body frame), 22 ... Engine, 24 ... Swing arm, 57 ... Axle, 58 ... Rear wheel, 62 ... Drive chain, 63 ... Chain adjuster, 85a, 86a ... Long hole, 85b ... Upper side of long hole, 85c ... lower side of long hole, 91 ... end cap, 92 ... adjustment screw (adjust bolt), 93 ... washer part, 93b ... through hole (axle insertion hole), 101 ... reinforcing plate.

Claims (2)

A swing arm attached to the vehicle body or the engine so as to be swingable up and down and having a long hole through which the rear wheel axle is passed at the rear end portion, an end cap that closes the rear end opening of the swing arm, and the end cap are passed through. An adjustment screw arranged in such a manner, a washer portion attached to the front end of the adjustment screw and having a through hole through which the axle passes, a drive chain for transmitting the driving force on the engine side to the rear wheel, In a motorcycle equipped with a chain adjuster that adjusts the tension of the drive chain by adjusting the position of the axle in the front-rear direction,
The end cap is attached with a reinforcing plate that is vertically spaced along the upper and lower sides of the elongated hole across the axle, and the reinforcing plate swings by attaching the end cap to the swing arm. A swing arm structure for a motorcycle, which is disposed in an arm and receives the axial force of the axle by the reinforcing plate.   The swing arm structure for a motorcycle according to claim 1, wherein the reinforcing plate has a front end formed in a U shape in a side view.

Images