JP5400662B2 - Swing arm structure for saddle-ride type vehicles - Google Patents

Description

  The present invention relates to a swing arm structure for a saddle-ride type vehicle.

  In a saddle-ride type vehicle, various shapes of swing arms have been proposed as swing arms that swingably support wheels. For example, the left and right arm shapes supporting the wheels are different (see, for example, Patent Document 1 (FIGS. 6 to 9)), and the left and right arm shapes are the same shape (for example, Patent Document 2 (FIG. 2 2)), or one that supports the wheel only by the left arm (see Patent Document 3 (FIG. 8)) has been proposed.

  7 to 8 of Patent Document 1, the swing arm 30 (the numbers in parentheses indicate the reference numerals described in each patent document. Element names are partially changed. The same applies hereinafter) and the left arm 31 and A right arm 32 and a cross member 33 connecting the left and right arms 31, 32, the left arm 31 is formed in a straight line, and the right arm 32 is bent upward. It is formed in a letter shape. That is, the shapes of the left and right arms are different when viewed from the side of the vehicle.

  In FIG. 9 of Patent Document 1, the cross member 33 is provided so as to be obliquely lowered from the right arm 32 positioned in the upper height direction over the entire width of the cross member to the left arm 31 positioned below. It has been. By forming the upper cross member serving as the upper surface of the cross member 33 and the lower cross member serving as the lower surface substantially parallel to each other, the stress applied to the cross member becomes uniform, so the shapes of the left and right arms 31 and 32 are different. However, it is easy to ensure the rigidity balance of the swing arm 30.

  FIG. 2 of Patent Document 2 discloses a swing arm 15 of a motorcycle formed by welding left and right arm halves 2 and 3 made of aluminum die casting on a center line in the vehicle body width direction. Here, the left and right arm halves 2 and 3 are cast using a mold having a die cutting direction parallel to the vehicle width direction. With such a structure, a swing arm formed by aluminum casting can be provided at low cost.

  In FIG. 8 of Patent Document 3, the rear structure of the vehicle body is attached to the upper surface of the cast cantilever swing arm 26 at the position offset to the one side from the center in the vehicle width direction on the upper surface of one rear cushion unit 27. Is disclosed. In such a vehicle body rear part structure, the force applied to the rear cushion unit 27 is input to the swing arm 26 from a portion close to one side in the vehicle width direction. In Patent Document 3, since the swing arm 26 is a cantilever type, there is no technical idea of securing a rigidity balance between the left and right arms.

  Here, as shown in Patent Document 1, a swing arm having a straight arm on one side and an arm formed on the other side in a U shape is divided into left and right halves as in Patent Document 2. When the left and right halved castings are manufactured by butt welding, the die removal direction is parallel to the vehicle width direction. It is difficult to arrange the side cross members so as to be substantially parallel to each other and to form the cross member portion so as to be inclined obliquely over the entire vehicle width direction from the straight arm side to the straight arm side. Since the upper cross member and the lower cross member cannot be arranged substantially parallel to each other, it is difficult to easily ensure the rigidity balance of the swing arm.

Further, for example, when a rear cushion unit shown in Patent Document 3 is attached to a saddle-ride type vehicle such as Patent Document 1 at a position offset to one side in the vehicle width direction on the upper surface of the swing arm. The rigidity balance of the swing arm becomes even more difficult to take.
If one rear cushion unit is attached to a swing arm provided with left and right deformed arms, it is preferable if there is a technique that can easily ensure the rigidity balance of the swing arm.

Japanese Patent No. 2673569 Japanese Patent No. 4005883 JP 2006-96266 A

  The present invention relates to a saddle-ride type vehicle having a swing arm in which one side is a straight arm and the other side is bent in a U-shape and welded to the left and right cast products, and one rear cushion unit is attached to the upper surface of the swing arm. It is an object of the present invention to provide a technique capable of easily ensuring a rigidity balance of a swing arm when it is attached at a position offset to one side in the vehicle width direction.

  The invention according to claim 1 has left and right arms on the left and right sides in the vehicle width direction, supports the rear wheel between the rear part of the left arm and the rear part of the right arm, and is swingable to the vehicle body side. A swing arm to be supported is provided, and a rear cushion unit is provided between the swing arm and the body frame to connect the body frame and the swing arm. When the vehicle is viewed from the side, it is a linear arm that exhibits a straight line shape, and the other arm of the left and right arms is a character-shaped arm that exhibits a U-shape when the vehicle is viewed from the side. The upper surface of the bent portion that bends upward to the U-shaped arm is set to be positioned above the upper surface of the linear arm, and an inclined surface is provided between the U-shaped arm and the linear arm. Cross member that has passed In the swing arm structure of the saddle-ride type vehicle, the left and right arms each have a U-shaped cross section that opens to the inner side in the vehicle width direction, and the lower end of the rear cushion unit is the upper part of the swing arm in the vehicle width direction. It is connected to the position offset from the center to the side of the letter-shaped arm, and the open ends opened to the inner side in the vehicle width direction of the left and right arms are offset toward the square-shaped arm side from the center line in the vehicle width direction. An inclined surface formed at the offset portion and formed on the upper portion of the cross member is provided in the vehicle width direction so as to extend from the center line in the vehicle width direction to the character-shaped arm side.

  In the invention according to claim 2, the side surface of the U-shaped arm is provided with a curved surface that curves inward in the vehicle width direction from the longitudinal axis of the rear cushion when the vehicle is viewed from above. Features.

  In the invention according to claim 3, the support shaft provided at the lower end of the rear cushion unit and connected to the upper portion of the swing arm is a bearing provided between the swing arm and the pivot shaft on the vehicle body side in the vehicle width direction. It arrange | positions so that it may overlap with.

  According to a fourth aspect of the present invention, when the inner surface of the U-shaped arm in the vehicle width direction is an inner side surface, a stopper projection is integrally formed on the inner side surface, and a caliper bracket is engaged with the stopper projection. The caliper bracket is provided with a rear brake caliper that applies a braking force to the rear wheel.

  The invention according to claim 5 is characterized in that a brake hose for connecting the brake caliper and the brake master cylinder extends above the U-shaped arm and on the inner side in the vehicle width direction than the rear cushion unit.

  In the invention according to claim 6, the lower surface of the bent portion of the U-shaped arm is set to be located above the lower surface of the linear arm, and the inclined surface formed at the lower portion of the cross member is: It is provided from the side surface of the U-shaped arm to the joint surface with the straight arm.

  According to the first aspect of the present invention, in a saddle-ride type vehicle having a swing arm welded with a left-right split casting product in which an arm on one side is straight and the other side is bent in a U-shape, one rear cushion is provided. When mounting the unit at a position offset to one side in the vehicle width direction on the upper surface of the swing arm, the open ends opened to the inside in the vehicle width direction of the left and right arms are a U-shaped arm rather than the center line in the vehicle width direction It is offset to the side and joined at this offset location.

  When the swing arms are formed by joining the open ends of the left and right cast mold arms to each other and the left and right arms have different shapes, the upper cross member constituting the upper part of the cross member is partially inclined with respect to the horizontal plane. May become larger. However, when the inclination of the upper cross member is partially increased, the stress generated on the surface with the large cross member is greatly different from the stress generated on the surface with the small inclination, and it becomes difficult to balance the rigidity of the left and right of the swing arm. There was a problem. Further, when one rear cushion unit is attached by being offset to one side in the vehicle width direction on the upper surface of the swing arm, there is a problem that the left and right rigidity balance of the swing arm becomes more difficult to take.

  In this regard, in the present invention, the lower end of the cushion unit is connected to the upper part of the swing arm at a position offset toward the U-shaped arm side in the vehicle width direction, and the open ends of the left and right arms are center lines in the vehicle width direction. Since the upper cross member to which the rear cushion unit is connected can be lengthened, the horizontal plane can be increased if the inclined surface becomes longer. The inclination with respect to becomes gentle. If the inclination of the upper cross member that receives the load from the rear cushion becomes gentle, the left and right stiffness balance of the swing arm can be easily balanced.

In the invention which concerns on Claim 2, the curved surface which curves to the vehicle width direction inside rather than the longitudinal direction axis | shaft of a rear cushion is provided in the side surface of the U-shaped arm.
If one rear cushion unit is offset from the center line in the vehicle width direction and the swing arm swings, the rear cushion unit is supported and the rigidity of the swing arm is located on the side where the rear cushion unit is placed. The letter-shaped arm that is being made will be higher.

  In the present invention, since the curved U-shaped arm with high rigidity is provided with a curved surface that curves inward in the vehicle width direction, the rigidity of the U-shaped arm side is reduced, and the rigidity balance of the left and right arms is optimal It becomes possible to keep on.

  In the invention according to claim 3, the longitudinal axis of the rear cushion is arranged so as to overlap with the bearing provided between the swing arm and the pivot shaft on the vehicle body side in the vehicle width direction.

  Since the bearing is provided below the rear cushion unit, the load from the rear cushion can be easily received by the bearing as compared with the case where the bearing is not provided below the rear cushion unit.

  In the invention which concerns on Claim 4, since the stopper protrusion is integrally formed in the inner surface located in the vehicle width direction of a U-shaped arm, compared with the case where a stopper protrusion is provided separately. The number of parts can be reduced. In addition, the support strength of the caliper bracket is increased.

  In the invention according to claim 5, the brake hose extends above the U-shaped arm. For this reason, foreign matter such as mud from below hits the U-shaped arm, making it difficult to hit the brake hose. In addition, the brake hose is disposed on the inner side in the vehicle width direction than the rear cushion unit. For this reason, foreign matter such as mud from the outside of the vehicle hits the rear cushion unit and hardly hits the brake hose. That is, foreign matter from the lower side of the vehicle is protected by the U-shaped arm, and foreign matter from the outside of the vehicle is protected by the rear cushion unit, so that the brake hose can be protected from foreign matter such as mud splashes.

  In the invention which concerns on Claim 6, even if the width | variety by the side of a letter-shaped arm is narrow in a lower cross member, by providing long inclined surface over the full width of a letter-shaped arm, The inclined surface and the inclined surface of the upper cross member can be formed substantially in parallel, and the left and right rigidity balance of the swing arm can be easily ensured.

1 is a left side view of a motorcycle according to the present invention. 1 is an exploded perspective view illustrating a vehicle body structure of a motorcycle according to the present invention. 1 is a left side view of a vehicle body central portion of a motorcycle according to the present invention. 1 is a right side view of a vehicle body central portion of a motorcycle according to the present invention. 1 is a plan view illustrating a vehicle body structure of a motorcycle according to the present invention. 1 is a plan view of a rear swing arm of a motorcycle according to the present invention. FIG. FIG. 8 is a view taken in the direction of arrow 8 in FIG. 6. FIG. 9 is a cross-sectional view taken along line 9-9 in FIG. 6. It is sectional drawing of the rear swing arm which concerns on an Example and a comparative example. It is the 11-11 line sectional view of FIG.

  Hereinafter, embodiments of the present invention will be described in detail. In the drawings and examples, “up”, “down”, “front”, “rear”, “left”, and “right” respectively indicate directions viewed from the driver who rides the motorcycle. The drawings are viewed in the direction of the reference numerals.

Embodiments of the present invention will be described with reference to the drawings.
As shown in FIG. 1, a motorcycle 10 includes a body frame 11, a front fork 15 that is provided on a head pipe 12 that constitutes a front portion of the body frame 11, and supports a front wheel 13 so as to be steerable. A pivot shaft 17 provided at the rear portion of the body frame 11, a swing arm 18 extending rearward from the pivot shaft 17, a rear wheel 21 attached to the rear end portion of the swing arm 18, and the body frame 11 are suspended. An engine 22 as a driving source, a seat rail 23 extending rearward from the rear portion of the body frame 11, and a seat supported by the seat rail 23 and disposed between the front wheel 13 and the rear wheel 21 and seated by a passenger And a sheet 24. This type of vehicle is called a saddle-type vehicle because an occupant rides on the seat 24.

  The engine 22 as a drive source includes a crankcase 27, a cylinder portion 28 extending obliquely upward from the crankcase 27, an intake system member 29 disposed above the cylinder portion 28, and a lower portion of the cylinder portion 28. And an exhaust system member 34 including a catalyzer 31, an exhaust pipe 32, and a silencer 33, and a radiator unit 35 disposed in front of the cylinder portion 28.

Next, components of the body frame will be described.
As shown in FIG. 2, the vehicle body frame 11 includes a head pipe 12, left and right main frames 37L and 37R extending obliquely rearward from the top of the head pipe 12, and the left and right main frames 37L. , 37R, and a pair of left and right center frames 38L, 38R that are partly extended in the vehicle height direction and a first cross member that is passed between the pair of left and right center frames 38L, 38R 41 and the second cross member 42, pivot plates 43L and 43R attached to the left and right center frames 38L and 38R, left and right down frames 44L and 44R extending downward from the lower part of the head pipe 12, and left The first left subframe 45L and the second left frame passed between the main frame 37L and the left down frame 44L And the sub-frame 46L, and a first and a right sub-frame 45R and the second right sub-frame 46R is passed between the right main frame 37R and the right down frame 44R.

  A first cross member 41 as a cross member is provided at the upper part of the center frames 38L and 38R, and a second cross member 42 is provided at the lower end of the center frames 38L and 38R. Pivot plates 43L and 43R are attached between the cross members 41 at positions where the center frames 38L and 38R extend in the height direction.

Hereinafter, an engine hanger having a role of holding the engine on the vehicle body frame will be described.
The left and right first engine hangers 51L and 51R each have a cylindrical shape and are joined to the lower ends of the left and right down frames 44L and 44R, and are located between the first engine hangers 51L and 51R and the engine. The first collar members 61 and 61 are arranged on the front. The first engine hangers 51L and 51R are provided with first hanger bolts 65 and nuts 66 that pass through the first engine hangers 51L and 51R and the first collar members 61 and 61 and suspend the engine on the vehicle body frame. .

  The left and right second engine hangers 52L and 52R are members each having a cylindrical shape, and are joined to the rear ends of the left and right main frames 37L and 37R. The second engine hangers 52L and 52R are provided with second hanger bolts 67 and nuts 68 that pass through the second engine hangers 52L and 52R and suspend the engine on the vehicle body frame.

  The third engine hangers 53L and 53R (only the reference numeral 53L on the front side of the figure is shown) are plate-like members extending from the left and right center frames 38L and 38R, and the left and right third engine hangers 53L and 53R. In addition, a third hanger bolt 69 and a nut 70 are provided through the left and right third engine hangers 53L and 53R to suspend the engine on the vehicle body frame. The fourth engine hanger 54 is a plate-like member extended from the second cross member 42.

In addition, a sub-hanger 73 for extending the engine 22 from the first cross member 41 to the front of the vehicle and extending from the vehicle body frame 11 is extended, and the upper end of the rear cushion 74 is attached to the rear of the vehicle from the first cross member 41 75 is extended.
That is, a plurality of engine hangers 50 including the first engine hanger 51 to the fourth engine hanger 54 are provided on the vehicle body frame 11, and the engine can be fastened to the plurality of engine hangers 50.

  The left and right pivot plates 43L and 43R provided in the pair of left and right center frames 38L and 38R are members for mounting the swing arm 18 that supports the rear wheels so as to be swingable. The left and right pivot plates 43L and 43R A swing arm 18 is disposed therebetween, and a swing arm bolt 77 as a pivot shaft penetrating the swing arm 18 and the left and right pivot plates 43L and 43R is provided. A rear cushion 74 is provided between the swing arm 18 and the vehicle body frame 11.

  As shown in FIGS. 3 and 4, the cylinder portion 28 of the engine 22 is supported by the first engine hangers 51L and 51R, and the upper part of the crankcase 27 of the engine is connected to the second engine hangers 52L and 52R and the second engine hangers 52L and 52R. 3 is supported by the engine hangers 53L and 53R, and the rear portion of the crankcase 27 of the engine is supported by the fourth engine hanger 54.

  A left step bracket 81L is attached to the left center frame 38L, a driver step 82L is attached to the front of the left step bracket 81L, and a change pedal 83 is provided in the vicinity of the driver step 82L. The passenger step 84L is attached to the rear portion of the left step bracket 81L. A chain cover 86 that covers the drive chain 85 is provided above the swing arm 18.

Next, a structure for supporting the upper end of the cushion unit will be described.
One engine hanger among the plurality of engine hangers 50 is a second engine hanger 52L, 52R as a main frame lower hanger provided at a lower portion of the main frames 37L, 37R, and forwards from the first cross member 41. The extending sub hanger 73 extends forward to a position adjacent to the rear of the second engine hangers 52L, 52R, and is a main frame fastening boss portion fastened to the second engine hangers 52L, 52R at the rear upper part of the engine 22. 91 and a sub-hanger fastening boss portion 92 fastened to the sub-hanger 73 are formed continuously.

  The sub hanger 73 is disposed close to the second engine hanger 52R, and the main frame fastening boss portion 91 and the sub hanger fastening boss portion 92 are continuously formed. The sub hanger 73 is fastened together with the main frame fastening boss part 91 as a boss part. Therefore, the sub-hanger fastening boss 92 can be kept small.

  When the vehicle is viewed from the right side, the shape of the right arm 96 as a component of the swing arm is a fold-shaped arm 97 formed in a fold shape, and the shape of the left arm 95 is Have different shapes.

  A right step bracket 81R is attached to the right center frame 38R, a driver step 82R is attached to the front of the right step bracket 81R, and a brake pedal 87 is provided in the vicinity of the driver step 82R. A passenger step 84R is attached to the rear portion of the right step bracket 81R.

  As shown in FIG. 5, a first cross member 41 is provided between a pair of left and right center frames 38 </ b> L and 38 </ b> R, and a rear cushion in which an upper end of a rear cushion 74 is attached to the rear portion of the first cross member 41. An upper mounting stay 75 (cushion upper mounting stay 75) is joined and fastened to the front upper portion of the first cross member 41 as a cross member and at a position adjacent to the cushion upper mounting stay 75 at the rear upper portion of the engine 22. Sub-hangers 73 are joined.

The cushion unit 74 is disposed offset to the right side from the center in the vehicle width direction.
Note that the cushion unit 74 may be arranged offset to the left from the center in the vehicle width direction.

A brake hose 107 that connects the brake caliper 105 and the brake master cylinder 106 extends above the cushion-shaped unit 74 in the vehicle width direction above the character-shaped arm 97 that forms the right side of the swing arm 18.
The brake hose 107 extends above the U-shaped arm 97 and further to the inner side in the vehicle width direction than the rear cushion 74.

  The brake hose 107 extends above the U-shaped arm 97. For this reason, foreign matter such as mud from below hits the U-shaped arm 97 and becomes difficult to hit the brake hose 107. In addition, the brake hose 107 is disposed on the inner side in the vehicle width direction than the rear cushion unit 74. For this reason, foreign matter such as mud from the outside of the vehicle hits the rear cushion unit 74 and becomes difficult to hit the brake hose 107. Foreign matter from below the vehicle is protected by the U-shaped arm 97 and foreign matter from the outside of the vehicle is protected by the rear cushion unit 74, so that the brake hose 107 can be protected from foreign matter such as mud splashes.

6 to 9, the detailed structure of the swing arm will be described.
As shown in FIG. 6, the swing arm 18 is swingably provided on pivot plates 43L and 43R provided on the vehicle body side. The swing arm 18 is supported on the vehicle body side.

The swing arm 18 includes a left arm 95 and a right arm 96 provided on the left and right of the vehicle width direction, and a swing arm cross member 111 serving as a cross member passed to the front portions of the left and right arms 95 and 96.
A rear wheel axle 115 is passed between the rear portion 113 of the left arm and the rear portion 114 of the right arm, and the rear wheel 21 is rotatably supported on the rear wheel axle 115.

  The rear wheel 21 includes a wheel 118 including a hub portion 117 and a tire 119 mounted around the wheel 118. A brake disk 122 is attached to the right side surface of the wheel 118, and a rear sprocket 124 is attached to the left side surface of the wheel 118 via a damper member 123. A drive chain 85 is wound around the rear sprocket 124.

  A chain slider 126 for guiding the driving chain 85 is attached to the upper surface 125 of the cross member. The chain slider 126 has an inverted T shape when viewed from the rear of the vehicle, and includes a seat portion 127, a rectangular guide portion 128 projecting upward from the seat portion 127, and a fixing portion 129 fixed to the swing arm 18. The guide portion 128 is disposed along the moving direction of the drive chain 85 to guide the drive chain 85. A screw member 131 is provided in the fixing portion 129, and the chain slider 126 is fixed by screwing the screw member 131 into the upper surface 125 of the cross member.

  Swing arm bolt supports 132 and 132 through which the swing arm bolt 77 passes are provided at the front end of the swing arm 18, and bearings 133 L and 133 R are fitted to the swing arm bolt supports 132 and 132, The swing arm 18 is made swingable about the axis.

The cross member 111 is provided with an upper cross member 135 that constitutes the upper surface 125 of the cross member, and a cushion unit support portion to which the lower end of the swing arm rear cushion 74 is attached to the upper surface of the upper cross member 135 to the right in the vehicle width direction. 136 is provided. A through hole 137 is formed in the cushion unit support portion 136, and a support shaft 138 is provided in the through hole 137. That is, the support shaft 138 is provided at the lower end of the rear cushion unit 74 and is connected to the upper portion of the swing arm 18.
The support shaft 138 is disposed at a position overlapping with a bearing 133R provided between the swing arm 18 and the pivot shaft 17 on the vehicle body side in the vehicle width direction.

  Since the bearing 133R is provided below the rear cushion unit 74, the load from the rear cushion 74 can be more easily received by the bearing 133R than when no bearing is provided below the rear cushion unit 74. .

  When the inner surface 98 is the inner side surface 98 of the U-shaped arm 97 as the right arm 96, a stopper projection 141 is integrally formed on the inner surface 98, and the caliper bracket is formed on the stopper projection 141. 142 is engaged, and the caliper bracket 142 is provided with a rear brake caliper 140 that applies a braking force to the rear wheel 21.

  Since the stopper protrusion 141 is integrally formed on the inner side surface 98 located on the inner side in the vehicle width direction of the U-shaped arm 97, the number of parts can be reduced compared to the case where the stopper protrusion 141 is provided separately. Can be reduced. In addition, the support strength (rigidity) of the caliper bracket is increased.

As shown in FIG. 7, the left arm 95 is a linear arm 99 having a linear portion 143 provided linearly when the vehicle is viewed from the left side.
A cover stay 148 to which a chain cover (reference numeral 86 in FIG. 3) is attached is projected from the left side of the swing arm 18 in the vehicle width direction.

  A cross member 111 is provided at the front portion of the left arm 95 so as to extend in the reverse direction from the diagram and reach the right arm. The cross member 111 has a flat surface 151 on the front side of the figure, and has an inclined surface 152 that continuously rises in the back direction from the drawing surface on the flat surface 151.

  Returning to FIG. 6, since the chain slider 126 is provided on the flat surface 151 and the drive chain 85 is guided, the drive chain 85 hits the inclined surface 152 when the swing arm 18 swings. Can be prevented.

  As shown in FIG. 8, when the vehicle is viewed from the right side, the right arm 96 is a U-shaped arm 97 provided in a U-shape, and at the upper end of the U-shaped arm 97, A cushion unit support 136 is provided.

Returning to FIG. 6, the side surface 153 of the U-shaped arm is provided with a curved surface 154 that curves inward in the vehicle width direction with respect to the longitudinal axis of the rear cushion when the vehicle is viewed from above.
When one rear cushion unit 74 is disposed offset with respect to the center line C in the vehicle width direction, when the swing arm 18 swings, the rear cushion unit 74 is supported, and the rigidity of the swing arm 18 is determined by the rear cushion unit 74. The letter-shaped arm 97 arranged on the side where the is provided is higher. Then, the rigidity of the U-shaped arm 97 becomes higher than that of the linear arm 99, making it difficult to balance the left and right rigidity.

  In this respect, in the present invention, since the curved U-shaped arm 97 having a high rigidity is provided with a curved surface 154 that curves inward in the vehicle width direction, the rigidity of the U-shaped arm 97 is reduced, and the left and right arms It becomes possible to keep the stiffness balance of 95 and 96 optimal.

  As shown in FIG. 9, the lower end of the rear cushion unit 74 is connected to a position offset from the center of the vehicle width direction toward the character arm 97 on the upper side of the swing arm 18, and left arm 95 and right arm 96. Each of which has a U-shaped cross section that opens to the inner side in the vehicle width direction, and the upper surface 166a of the bent portion 166 that bends upward of the U-shaped arm 97 is longer than the upper surface 99a of the linear arm 99 ( The open ends 157 and 158 which are set so as to be positioned at the upper side by H1) and opened to the inner side in the vehicle width direction of the left and right arms 95 and 96 have a length on the side of the U-shaped arm 97 from the vehicle width direction center line C It is offset by δ and joined at the offset location. A reinforcing rib 169 extending toward the center in the vehicle width direction is provided on the inner surface of the linear arm 99.

The swing arm cross member 111 has inclined surfaces 152 and 155 on the upper surface and the lower surface, and the inclined surface 152 formed on the upper portion of the cross member 111 is formed in a shape that is heavier than the center line C in the vehicle width direction. It is provided over the arm 97 side. Similarly, an inclined surface 155 formed at the lower portion of the cross member 111 is provided from the side surface 153 of the U-shaped arm 97 to the joint surface 168 with the linear arm 99.
Further, the lower surface 166b of the bent portion 166 of the fold-shaped arm 97 is set to be positioned above the lower surface 99b of the linear arm 99 by a length (H2).

Next, the operation of the swing arm structure of the saddle-ride type vehicle described above will be described.
FIG. 10 (a) shows an embodiment, in which one arm is a straight arm 99 (straight arm 99) and the other arm is bent in a U-shape. Cross-member that constitutes the top surface of the swing arm with one rear cushion unit (FIG. 9, reference numeral 74) in a saddle-ride type vehicle having a swing arm 18 welded with a left and right split cast product, which is shaped like an arm 97) Of the left and right arms 95 and 96, the open ends 157 and 158 opened to the inside in the vehicle width direction are formed in a shape that extends from the center line in the vehicle width direction. It is offset to the side of the arm 97 and joined at this offset location.

  FIG. 10B shows a comparative example, and the open ends 157B and 158B of the left and right arms are usually provided at the center in the vehicle width direction, and the open ends 157B and 158B are the center in the vehicle width direction. If it is provided in C, the inclination angle (θb) of the upper cross member 135B constituting the upper part of the cross member 111B with respect to the horizontal plane is more than the inclination angle (θa) when offset from the center line to the character arm side It is necessary to make a large angle (θa <θb). However, when the inclination angle (θb) of the upper cross member 135B is increased, the stress generated on the inclined surface of the cross member is significantly different from the stress generated on the non-inclined portion, and it is difficult to balance the rigidity on the left and right of the swing arm. There was a problem.

  Referring back to FIG. 10A, the open ends 157 and 158 of the left and right arms are offset by a length δ on the side of the character-shaped arm 97 to the center line C in the vehicle width direction, and are joined at this offset portion. Therefore, if the inclined surface 152 of the upper cross member that receives the cushion load becomes longer and the inclined surface 152 becomes longer, the inclination angle (θa) with respect to the horizontal plane becomes gentle. If the inclination angle (θa) of the inclined surface 152 of the upper cross member becomes gentle, the inclined surface 155 of the lower cross member 134 and the inclined surface 152 of the upper cross member can be formed substantially in parallel. If the upper and lower cross members 134 and 135 are formed substantially parallel to each other, the stress generated on the inclined surface of the cross member is not significantly different from the case where the upper and lower cross members 134 and 135 are not formed substantially parallel. The right and left rigidity balance of the arm 18 can be easily secured.

  Further, even if the width of the U-shaped arm 97 side is narrow in the lower cross member 134, the inclined surface 155 is provided long over the entire width of the U-shaped arm 97, so that the inclination of the lower cross member 134 is increased. The surface 155 and the inclined surface 152 of the upper cross member 135 can be formed substantially in parallel, and the left and right stiffness balance of the swing arm can be easily ensured.

Next, a modification of the chain slider will be described.
As shown in FIG. 11, a U-shaped hook portion 162 is provided at the rear end of the chain slider 126, and the hook portion 162 is engaged with an engaging portion 162 attached to the left arm 95. The hook portion 162 has a vertical portion 164 that hangs downward from the rear end of the seat portion 127, and a folding portion that extends from the vertical portion 164 toward the engaging portion 162 that extends in a flange shape to the seat portion 127. Part 165.

  If the hook 162 is provided on the chain slider 126, the rear end of the chain slider 126 can be securely attached to the swing arm 18 without increasing the number of screw members (FIG. 6, reference numeral 131). Therefore, an increase in the number of parts and an increase in assembly man-hour can be suppressed.

  Although the present invention is applied to a motorcycle in the embodiment, it can also be applied to a saddle-ride type three-wheel vehicle (three-wheel buggy) and a saddle-ride type four-wheel vehicle (four-wheel buggy). It can be applied to a ride type vehicle.

  The present invention is suitable for a motorcycle provided with swing arms having different left and right arm shapes.

  DESCRIPTION OF SYMBOLS 10 ... Riding type vehicle (motorcycle), 11 ... Body frame, 17 ... Pivot shaft, 18 ... Swing arm, 21 ... Rear wheel, 74 ... Cushion unit, 95 ... Left arm (linear arm), 96 ... Right arm (U-shaped arm), 98 ... Inner surface of the U-shaped arm, 99 ... Linear arm, 99a ... Upper surface of the linear arm, 99b ... Lower surface of the linear arm, 106 ... Brake master cylinder, 107 ... Brake Hose, 111 ... cross member (swing arm cross member), 113 ... rear part of left arm, 114 ... rear part of right arm, 133R ... bearing, 138 ... support shaft, 140 ... rear brake caliper, 141 ... stopper protrusion, 142 ... Caliper bracket, 154 ... curved surface, 157 ... open end of left arm, 158 ... open end of right arm, 166 ... bent portion, 1 6a ... bent portion of the upper surface, a lower surface of 166b ... bend.

Claims (6)

A left arm (95) and a right arm (96) are provided on the left and right in the vehicle width direction, and the rear wheel (21) is supported between the rear part of the left arm (95) and the rear part of the right arm (96). A swing arm (18) supported swingably on the vehicle body side is also provided, and between the swing arm (18) and the vehicle body frame (11), the vehicle body frame (11) and the swing arm (18) are provided. A linear arm (99) that is provided with a cushion unit (74) for connecting the left and right arms and exhibits a straight line when one of the left and right arms (95, 96) is viewed from the side of the vehicle. The other arm of the left and right arms (95, 96) is a U-shaped arm (97) that has a U-shape when the vehicle is viewed from the side. Bending part that bends above the arm (97) ( 66) is set to be positioned above the upper surface of the linear arm (99), and an inclined surface is provided between the U-shaped arm (97) and the linear arm (99). In a swing arm structure of a saddle-ride type vehicle to which a cross member (111) having
The left and right arms (95, 96) each have a U-shaped cross section that is open inward in the vehicle width direction,
The lower end of the cushion unit (74) is connected to the upper portion of the swing arm (18) at a position offset from the center in the vehicle width direction toward the character-shaped arm (97),
Open ends of the left and right arms (95, 96) opened inward in the vehicle width direction are offset from the center line in the vehicle width direction toward the U-shaped arm (97), and are joined at the offset locations. ,
A saddle riding characterized in that an inclined surface formed at an upper portion of the cross member (111) is provided in the vehicle width direction so as to extend from the center line in the vehicle width direction to the character-shaped arm (97) side. Type swing arm structure.   A curved surface (154) that curves inward in the vehicle width direction from the longitudinal axis of the cushion unit (74) when the vehicle is viewed from above is provided on a side surface of the U-shaped arm (97). The swing arm structure of a saddle-ride type vehicle according to claim 1, wherein   A support shaft (138) provided at a lower end of the cushion unit (74) and connected to an upper portion of the swing arm (18) is configured so that the swing arm (18) and a pivot shaft (17) on the vehicle body side in the vehicle width direction are provided. The swing arm structure of a saddle-ride type vehicle according to claim 1 or 2, wherein the swing arm structure is disposed so as to overlap with bearings (133L, 133R) provided between the two.   When the inner surface of the U-shaped arm (97) in the vehicle width direction is an inner surface, a stopper projection (141) is integrally formed on the inner surface, and a caliper bracket is formed on the stopper projection (141). The rear brake caliper (140) for applying a braking force to the rear wheel (21) is provided on the caliper bracket (142). A swing arm structure for a saddle-ride type vehicle according to claim 3.   A brake hose (107) that connects the rear brake caliper (140) and the brake master cylinder (106) above the U-shaped arm (97) and on the inner side in the vehicle width direction than the cushion unit (74) The swing arm structure for a saddle-ride type vehicle according to claim 4, wherein: The lower surface of the bent portion (166) of the U-shaped arm (97) is set to be positioned above the lower surface of the linear arm (99), and
An inclined surface formed at a lower portion of the cross member (111) is provided from a side surface of the U-shaped arm (97) to a joint surface with the linear arm (99). The swing arm structure of the saddle-ride type vehicle according to any one of 1 to 5.

Images