JP6035025B2 - Motorcycle - Google Patents

Description

  The present invention relates to a motorcycle including a cast swing arm.

  2. Description of the Related Art In recent years, in motorcycles, swing arms made of aluminum alloy or magnesium alloy have been adopted in order to reduce weight and improve product appeal. Furthermore, in order to promote weight reduction, a hollow casting swing arm has been proposed (see, for example, Patent Document 1 (FIGS. 4 and 7)).

  When forming a hollow casting swing arm by a method such as gravity casting or die casting, the sand core is housed in a mold and poured into a cavity formed between the mold and the sand core. I boil water. The sand core is held by a baseboard, keren (metal supporting the core) or a part of a mold (hereinafter referred to as a baseboard or the like) so that the sand core is not displaced by the molten metal.

Specifically, as shown in FIG. 7 of Patent Document 1, the core (42) (the numbers in parentheses indicate the symbols described in Patent Document 1. The same applies hereinafter) to the baseboard (43), (50). Is provided.
In the hollow cast part (27), as shown in FIG. 4 of Patent Document 1, a communication hole (36) is formed inside by the baseboard (43), and a communication hole (37) is formed on the upper surface by the baseboard (50). it can.

  The communication hole (37) formed on the upper surface has less influence on the design than the side surface, but it is still not preferable because it can be visually recognized from the outside, and in addition, rain and the like easily enter. As a countermeasure, it is conceivable to close the communication hole (37) with a cap or the like, but this results in an increase in the number of parts.

  Therefore, a swing arm that can make it difficult to visually recognize a baseboard hole from the outside without increasing the number of parts is required.

JP 2011-105213 A

  It is an object of the present invention to provide a motorcycle including a swing arm that can make it difficult to visually recognize a baseboard hole or the like from the outside without increasing the number of parts.

According to a first aspect of the present invention, there is provided a motorcycle including a swing arm in which left and right rear arm portions extending rearward of the vehicle are integrally formed with a swing arm front portion extending in the vehicle width direction and connecting the left and right rear arm portions. The front part of the swing arm has a hollow part, and a hole connecting the hollow part and the outside is formed through the upper surface, the hole is covered with a functional member equipped on the vehicle, and the functional member guides the brake hose. It is characterized by being a hose guide or a chain slider for guiding the drive chain.

The invention according to claim 2 is characterized in that a plurality of holes are arranged along a line extending rearward of the vehicle.

The invention according to claim 3 is characterized in that the holes are respectively provided on the left and right sides in the vehicle width direction of the front portion of the swing arm , the hose guide is covered on one of the left and right holes, and the chain slider is covered on the other hole. To do.

In the invention according to claim 4, the front part of the swing arm accommodates a fastening part attaching part for attaching the hose guide with a rotary fastener such as a screw and a protrusion extending from the hose guide in the vicinity of the hole where the hose guide is covered. Protruding storage recesses are provided.

In the invention which concerns on Claim 1, a core hole is covered with a functional member. Since the cast hole is covered with the functional member, it is difficult to visually recognize the cast hole from the outside, and the appearance can be improved. In addition, since the cast hole is covered with the functional member, it becomes difficult for rain or the like to enter the hollow portion. Further, since the functional member is a member that is permanently installed in the motorcycle, the number of parts does not increase.
Therefore, according to the present invention, there is provided a motorcycle including a swing arm that makes it difficult to visually recognize a baseboard hole (cast hole) or the like without increasing the number of parts.
In addition, since the punched hole is covered with the functional member, the sound that resonates in the swing arm (the hollow portion at the front of the swing arm) becomes difficult to leak, and the resonance sound can be substantially reduced.
The functional member is a hose guide for guiding the brake hose or a chain slider for guiding the drive chain.
The hose guide and the chain slider are arranged along a line extending rearward of the vehicle. Even if the core hole is covered with a hose guide or a chain slider, there is no unnaturalness. Since the hose guide or the chain slider is a member that is permanently installed in the motorcycle, the number of parts does not increase.

  In the invention according to claim 2, a plurality of the cast holes are arranged along a line extending rearward of the vehicle. Since the plurality of punched holes are arranged along the line, the functional parts are arranged efficiently along the line extending rearward of the vehicle.

In the invention according to claim 3, the hose guide is put on one of the left and right cast holes, and the chain slider is put on the other cast hole. The left and right cast holes can be efficiently covered with the hose guide and the chain slider.

In the invention according to claim 4, the front part of the swing arm has a fastening part attaching part for attaching the hose guide with a rotary fastener such as a screw in the vicinity of the cast hole where the hose guide is covered, and a protrusion extending from the hose guide. A protrusion receiving recess for storing the is provided.
The hose guide can be prevented from rotating by inserting the protrusion into the protrusion housing recess. Then, the hose guide can be fixed with one or one rotary fastener. The number of fasteners can be reduced rather than fixing with a plurality of rotary fasteners, and in addition, the hose guide can be simplified and reduced in weight.

Fig. 2 is a plan view of the rear part of the motorcycle according to the present invention. FIG. 2 is a sectional view taken along line 2-2 of FIG. It is sectional drawing of the swing arm which concerns on this invention. It is a top view of the lower mold for casting. FIG. 5 is a sectional view taken along line 5-5 of FIG. It is an effect | action figure of a sand hole. It is a top view of a swing arm casting. FIG. 8B is a cross-sectional view taken along line 8-8 in FIG. FIG. 9 is a cross-sectional view taken along line 9-9 in FIG.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. In the description, front and rear, and left and right are based on a passenger on a motorcycle. The drawings are to be viewed in the direction of the reference numerals.

  As shown in FIG. 1, the swing arm 30 includes a pivot portion 31 connected to a vehicle body frame 11 of the motorcycle 10 by a pivot shaft 12, and a U-shaped swing arm front portion extending from the pivot portion 31 toward the rear of the vehicle. 32, a left rear arm portion 33L (L is a subscript indicating the left, the same applies hereinafter) and a right rear arm portion 33R (R is a right side) extending rearward of the vehicle so as to sandwich the rear wheel 13 from the swing arm front portion 32. Subscript to indicate (the same applies below). The left rear arm portion 33L and the right rear arm portion 33R rotatably support the rear wheel 13 via the rear wheel axle 14.

  A brake disc 16 is fixed to the right hub 15R of the rear wheel 13. A caliper bracket 17 is supported on the rear wheel axle 14, and a brake caliper 19 including friction plates 18 and 18 is attached to one end of the caliper bracket 17. By sandwiching the brake disc 16 between the friction plates 18 and 18 of the brake caliper 19, the rear wheel 13 can be braked. At this time, the other end of the caliper bracket 17 is locked to the rotation stop piece 34 extending from the right rear arm portion 33R so that the caliper bracket 17 does not rotate due to the reaction.

  A driven sprocket 21 is attached to the left hub 15L of the rear wheel 13. A drive chain 22 is wound around the driven sprocket 21, power is transmitted by the drive chain 22, and the rear wheel 13 is rotated.

If the play (deflection) of the drive chain 22 becomes excessive, the drive chain 22 may come off the driven sprocket 21. When the drive chain 22 is disengaged toward the vehicle width center 40, the drive chain 22 is placed on the left hub 15L. When the drive chain 22 is disengaged outside the vehicle body (in the direction away from the vehicle width center 40), the drive chain 22 falls to the left rear arm portion 33L.
In the present invention, the chain receiving piece 35 is extended from the left rear arm portion 33L to the vehicle width center 40, and the drive chain 22 is received by the chain receiving piece 35. Thereby, there is no fear that the drive chain 22 falls into the gap between the left rear arm portion 33L and the rear wheel 13 and gets caught.

As shown in FIG. 2, the left rear arm portion 33L includes an outer wall portion 37L, an upper flange portion 38L extending from the upper end of the outer wall portion 37L to the vehicle width center 40, and a lower end of the outer wall portion 37L to the vehicle width center 40. The lower flange portion 39L extends, and exhibits a U-shaped cross-sectional shape that opens toward the vehicle width center 40 side. Similarly, the right rear arm portion 33R includes an outer wall portion 37R, an upper flange portion 38R extending from the upper end of the outer wall portion 37R to the vehicle width center 40, and a lower flange portion extending from the lower end of the outer wall portion 37R to the vehicle width center 40. 39R, and exhibits a U-shaped cross-sectional shape opening toward the vehicle width center 40 side.
Since there is no inner wall, the left and right rear arm portions 33L and 33R are lightened.

A rotation stopper piece 34 is integrally formed on the outer wall portion 37 of the right rear arm portion 33R.
If a separately prepared rotation stop piece 34 is retrofitted to the right rear arm portion 33R, the number of parts increases and the number of mounting steps is required. In this respect, by integrally forming in this example, the number of parts can be reduced and the manufacturing cost can be reduced.
In addition, since the rotation stopper piece 34 extends from the outer wall portion 37R to the vehicle width center 40, it is shielded by the outer wall portion 37R and the upper flange portion 38R and is difficult to see from the outside. That is, even if the rotation stop piece 34 is provided, the design is not affected.

A chain receiving piece 35 is integrally formed with the upper flange portion 38 of the left rear arm portion 33L.
If a separately prepared chain receiving piece 35 is retrofitted to the left rear arm portion 33L, the number of parts increases and an installation man-hour is generated. In this respect, by integrally forming in this example, the number of parts can be reduced and the manufacturing cost can be reduced.
In addition, the chain receiving piece 35 as a measure against the dropping of the chain can be easily provided on the left rear arm portion 33L by integral formation, and a measure against the dropping of the chain can be promoted.

By the way, since the earth and sand on the road surface is wound up by the rear wheel 13 shown in FIG. 1, earth and sand are easily attached to the left and right rear arm portions 33L and 33R. As a result, as shown in FIG. 2, sediments 42 and 42 due to earth and sand are likely to be deposited at inner corners 41L and 41R between the outer wall portions 37L and 37R and the lower flange portions 39L and 39R. Since the deposits 42 and 42 are shielded by the outer wall portions 37L and 37R and the upper flange portions 38L and 38R, they cannot be seen from the outside. Further, since the outer wall portions 37L and 37R are substantially vertical surfaces, it is difficult for sediment to accumulate. When earth and sand are placed on the upper surfaces of the upper flange portions 38L and 38R, they fall off due to vibration and are difficult to accumulate.
Therefore, according to the present invention, a swing arm 30 that can make it difficult to see dirt and the like from the outside is provided.

Next, the internal structure of the swing arm 30 will be described with reference to FIG.
FIG. 3 is a plan sectional view of the swing arm. The swing arm 30 includes a pivot portion 31, a swing arm front portion 32, and left and right rear arm portions 33L and 33R.

In particular, the swing arm front portion 32 includes a left front arm portion 43L and a right front arm portion 43R extending from the pivot portion 31, and a rear portion of the left front arm portion 43L and a rear portion of the right front arm portion 43R in the vehicle width direction. And the swing arm front portion 32 has a hollow structure. The vehicle width direction outer surfaces of the pair of left and right front arm portions 43L and 43R and the vehicle width direction outer surfaces of the left and right rear arm portions 33L and 33R are formed as continuous surfaces.
A cast hole 46 (four in this example) is left on the bottom 45 of the swing arm front portion 32 as a trace of the support pin (FIG. 4, reference numeral 63) being pulled out.

A sanding hole 48 is provided in the front wall 47 of the cross portion 44, and a sanding hole 52 is provided in the rear wall 51.
Further, the swing arm front part 32 and the left and right rear arm parts 33L, 33R are partitioned by partition walls 53L, 53R, and these partition walls 53L, 53R are positioned at the rear of the vehicle closer to the vehicle width center 40. It is provided with an inclination. That is, the angle α1 between the partition walls 33L and 33R and the outer wall of the swing arm front portion 32 is an obtuse angle (an angle exceeding 90 °), and this angle α1 can be increased, and sand removal from the swing arm front portion 32 is enhanced. It is done.

  As shown in FIG. 1, a large opening 55 surrounded by the pivot portion 31, the left front arm portion 43 </ b> L, the right front arm portion 43 </ b> R, and the cross portion 44 is formed. The opening 55 can reduce the weight of the swing arm 30.

The swing arm 30 having such a structure is manufactured by casting. A casting mold for this purpose will be described next.
As shown in FIG. 4, left and right slide rods 62L and 62R are movably inserted into the lower mold 61 of the casting mold 60, and a plurality of (four in this example) support pins 63 are vertically moved (from the front to the back of the drawing). F) The left and right slide molds 64L and 64R are set, and the links 65L and 65R and the driver 66 for driving the left and right slide molds 64L and 64R are set.
Since the partition walls 53L and 53R are inclined, the left and right slide molds 64L and 64R can be moved to the center simply by pulling the driver 66 backward.

  Note that the left and right slide molds 64L and 64R may be sand molds (sand cores). That is, the sand mold is suitable for low-volume, multi-product production, and the slide mold is suitable for mass production, and any one can be selected in consideration of the production amount.

  Separately, a sand core 67 having an H shape in a plan view is formed. Baseboards 68 and 69 are extended forward and backward from the sand core 67. Receiving recesses 71, 72 that support these baseboards 68, 69 are provided in the island portions 73, 74 of the lower mold 61. The sand core 67 is attached to the lower mold 61 in the manner of placing the baseboards 68 and 69 on the receiving recesses 71 and 72 and placing them on the support pins 63.

As shown in FIG. 5, the upper die 76 is put on the lower die 61, and the rise of the sand core 67 is suppressed by the pressing pins 77 and 77 extending from the upper die 76. The sand core 67 shown in FIG. 4 has a large plane area because it plays the role of manufacturing a hollow swing arm front portion (FIG. 3, reference numeral 32). Therefore, in this example, the front and rear baseboards 68 and 69 prevent horizontal movement, and the support pins 63 and 63 and the pressing pins 77 and 77 shown in FIG. 5 prevent vertical movement.
In this state, the molten metal is filled into the cavity 78, but there is no concern that the sand core 67 is displaced by the molten metal.

  Preferably, the upper die 76 is provided with a fastener pin 84 and a recess pin 85 so as to extend partway through the cavity 78.

  When the molten metal solidifies, the holding pins 77 and 77 are moved upward, and the support pins 63 and 63 are moved downward to be removed from the cast product. Further, the slide rods 62L and 62R shown in FIG. 4 are moved horizontally to be removed from the cast product, and the left and right slide molds 64L and 64R are moved along the partition walls 53L and 53R indicated by imaginary lines to be removed from the cast product. The cast product is removed from the lower mold 61 by removing the upper mold 76 of FIG.

The sand core 67 remains in the obtained casting (hereinafter referred to as swing arm casting).
Therefore, as shown in FIG. 6, the sand core 67 is scraped out from the sanding holes 48 and 52. The front wall 47 faces a front space (FIG. 3, opening 55) formed between the pivot portion 31 and the left and right front arm portions 43L and 43R, and sand can be scraped into the front space.
Similarly, the rear wall 51 faces a rear space formed between the left and right rear arm portions 33L and 33R, and sand can be scraped into the rear space, so that the sand core 67 can be scraped out easily.
As a result, the swing arm front portion 32 can be easily made hollow.

  Sanding holes 48 and 52 are provided in the front wall 47 and the rear wall 51 of the cross portion 44. If it is this position, it is hard to see from the side and the design property can be improved.

  The completed swing arm casting 79 is shown in FIG. On the upper surface of the swing arm casting 79, two cast holes 81 which are marks of the pressing pins (FIG. 5, reference numerals 77 and 77) remain on the left side, and two cast holes 82 remain on the right side.

The plurality of punched holes 81 are disposed along a line 86 that extends rearward of the vehicle, and the plurality of punched holes 82 are disposed along a line 87 that extends rearward of the vehicle.
In addition, a fastening portion mounting portion 88 formed by a fastening pin (FIG. 5, reference numeral 84) and a protrusion housing recessed portion 89 formed by a recessed pin (FIG. 5, reference numeral 85) are integrally formed around the right hole 82, etc. It is formed.

  As shown in FIG. 7B, the chain slider 23 is put on the left punching hole 81 in a later step. Specifically, a protrusion 23 a extends from the lower surface of the chain slider 23 to the back of the drawing, and the protrusion 23 a is fitted into the cast hole 81. A tightening hole 95 is provided in the chain slider 23, and the tightening hole 95 is fastened through a fastener 96 such as a screw or a bolt. Since the projection 23a plays a role of positioning and rotation prevention, the chain slider 23 can be fixed with a small number of fasteners 96.

The chain slider 23 is a member that guides the rollers of the drive chain 22. In addition, the hose guide 24 is put on the right cast hole 82 in a later step.
Therefore, the punched holes 81 and 82 may remain in the swing arm casting 79.

The chain slider 23 and the hose guide 24 are one of functional members that are permanently installed in a vehicle (motorcycle). The functional member includes various covers, and is not limited to the chain slider 23 or the hose guide 24.
Since the cast holes 81 and 82 are covered with the chain slider 23 and the hose guide 24 as functional members, the cast holes 81 and 82 are hardly visible from the outside, and the appearance can be improved.

In addition, since the core holes 81 and 82 are covered with the functional member, rain or the like hardly enters the hollow portion. Further, since the functional member is a member that is permanently installed in the motorcycle, the number of parts does not increase.
In addition, since the punched holes 81 and 82 are covered with the functional member, the sound that resonates within the swing arm (the hollow portion at the front of the swing arm) becomes difficult to leak, and the resonance noise is substantially reduced. be able to.

  The hose guide 24 and the chain slider 23 are disposed along lines 86 and 87 extending rearward of the vehicle. Even if the cast hole is covered with the hose guide 24 or the chain slider 23, there is no unnaturalness. Since the hose guide 24 or the chain slider 23 is a member that is permanently installed in the motorcycle, the number of parts does not increase.

  As shown in FIG. 8, the hose guide 24 is a clamper that holds the brake hose 91, and by screwing a rotary fastener 92 such as a screw, a screw, or a bolt into the fastening portion mounting portion 88, the front portion of the swing arm 32. Note that the protrusion 93 formed by bending from the hose guide 24 is inserted into the protrusion housing recess 89 before the rotation.

  By inserting the protrusion 93 into the protrusion housing recess 89, the hose guide 24 can be prevented from rotating. Then, the hose guide 24 can be fixed by one or one rotary fastener 92. The number of fasteners can be reduced as compared with fixing with a plurality of rotary fasteners. In addition, the hose guide 24 has only one through hole 94 through which the rotary fastener 82 is passed. The hose guide 24 can be simplified and reduced in weight.

  The fastening portion mounting portion 88 is preliminarily threaded after casting. Since the projection housing recess 89 is integrally formed by casting and the prepared hole of the fastening portion mounting portion 88 is formed by casting, machining performed after casting can be reduced. However, the fastening pin 84 and the recess pin 85 in FIG. 5 may be omitted, and the fastening portion mounting portion 88 and the protrusion housing recess 89 in FIG. 8 may be provided by machining after casting.

  As shown in FIG. 9, a positioning projection 23 a extends from the lower surface of the chain slider 23. By fitting the protrusion 23a into the cast hole 81, the chain slider 23 can be positioned and prevented from rotating.

  In the embodiment, the left rear arm portion is provided with a rotation stopper piece and the right rear arm portion is provided with a chain receiving piece. However, when the chain is arranged on the right side of the vehicle width center, the right rear arm A rotation stopper piece may be provided on the part, and a chain receiving piece may be provided on the left rear arm part.

  The swing arm of the present invention is suitable for a motorcycle, but can also be applied to a three-wheeled vehicle or a four-wheeled vehicle in which a swing arm is extended from a body frame and a wheel is rotatably attached to the swing arm.

  The swing arm of the present invention is suitable for a motorcycle in which appearance and design are regarded as important.

  DESCRIPTION OF SYMBOLS 10 ... Motorcycle, 22 ... Chain (drive chain), 23 ... Functional member (chain slider), 24 ... Functional member (hose guide), 30 ... Swing arm, 31 ... Pivot part, 32 ... Swing arm front part, 33L, 33R: Left and right rear arm portions, 67: Core (sand core), 68 ... Baseboard, 81, 82 ... Cast hole, 86, 87 ... Line extending rearward of vehicle, 88 ... Fastening portion mounting portion, 89 ... Projection storage recess, 91 ... brake hose, 82 ... rotary fastener, 93 ... projection.

Claims (4)

A swing arm (30) integrally formed with left and right rear arm portions (33L, 33R) extending rearward of the vehicle and a swing arm front portion (32) extending in the vehicle width direction and connecting the left and right rear arm portions (33L, 33R). In the motorcycle (10) provided with
The swing arm front portion (32) includes a hollow portion, and holes (81, 82) connecting the hollow portion and the outside are formed through the upper surface, and the holes (81, 82) are mounted on the vehicle. Covered with functional members,
The functional member is a hose guide (24) for guiding the brake hose (91) or a chain slider (23) for guiding the drive chain (22).
Motorcycle characterized by that. The motorcycle according to claim 1, wherein a plurality of the holes (81, 82) are arranged along a line (86, 87) extending rearward of the vehicle. Said hole (81, 82) wherein each is provided left and right in a vehicle width direction of the swing arm front (32), said hose guide one of the left and right front Kiana (82) (24) is put, while the The motorcycle according to claim 2, wherein the chain slider (23) is put over the hole (81). A fastening portion for attaching the hose guide (24) to the swing arm front portion (32) with a rotary fastener (92) such as a screw in the vicinity of the hole (82) where the hose guide (24) is covered. The motorcycle according to claim 3, further comprising a mounting portion (88) and a projection receiving recess (89) for storing a projection (93) extending from the hose guide (24).

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