JP2017024510A - Vehicle body frame structure of motorcycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle body frame structure of a motorcycle capable of efficiently improving the rigidity of a main frame having a curved part curved upward toward the rear.SOLUTION: In a vehicle body frame structure of a motorcycle, a main frame 6L comprises: a floor frame part 7 extending toward the rear of a vehicle body substantially along a step floor of the vehicle body from a down frame; and a curved part 8 curved upward toward the rear from the rear part of the floor frame part 7. The main frame 6L is provided with a pair of frame plate members having a substantially hat-shaped cross section laterally joined to each other at respective flange parts. A reinforcement plate 22 extending substantially along the curved part 8 is sandwiched to be disposed in an area extending over the curved part 8 between the frame plate members of the pair.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a body frame structure of a motorcycle such as a scooter type vehicle.

  2. Description of the Related Art A body frame of a motorcycle is known in which a pair of frame plate members having a substantially hat-shaped cross section are joined from the left and right in the vehicle width direction to form a closed cross section (see, for example, Patent Document 1).

  In the body frame described in Patent Document 1, the main frame whose front end is joined to the head pipe is bent downward at the front side position of the seat on which the driver sits after the main frame extends toward the rear side of the body. Yes. The main frame has a closed cross-section structure by joining a pair of frame plate members having a substantially hat-shaped cross section from the left and right in the vehicle width direction. In addition, a reinforcing plate is sandwiched between the left and right frame plate members in the front extending portion on the front side of the bent portion of the main frame and the lower extending portion on the lower side of the bent portion. It is welded to the frame plate member. Thereby, the rigidity and intensity | strength of the front extension part into which the load from an engine or a seat is directly input, and the downward extension part into which a load is directly input from a swing arm are partially improved by a reinforcement board.

JP-A-6-8868

  In the above-mentioned conventional body frame, the rigidity and strength of the portion where the direct load is input from the engine, seat, swing arm, etc. are partially enhanced by the reinforcing plate, but the rigidity in the extending direction of the main frame is efficient. It is not raised well. In particular, in a vehicle body frame having a curved portion that is curved toward the upper side of the rear portion of the main frame, it is desired to efficiently increase the rigidity before and after the curved portion where large stress tends to concentrate.

  Accordingly, the present invention is intended to provide a vehicle body frame structure for a motorcycle that can efficiently increase the rigidity of a main frame having a curved portion that curves upward at the rear.

  In order to solve the above problems, a body frame structure for a motorcycle according to the present invention includes a head pipe (4) that supports the front wheels so as to be steerable, and a down frame that extends downward from the head pipe (4) ( 5) and a main frame (6L) extending from the lower part of the down frame (5) toward the rear side of the vehicle body, and the main frame (6L) is a step of the vehicle body from the down frame (5). A floor frame portion (7) extending toward the rear of the vehicle body substantially along the floor (3), and a curved portion (8) curved from the rear portion of the floor frame portion (7) toward the rear upper portion. In the body frame structure of a motorcycle, the main frame (6L) includes a pair of frame plate members (20i, 20o) having a substantially hat-shaped cross section, and flange portions (20i-f, 20o). f) Reinforcing plates (not shown) that are joined to each other from the left and right in the vehicle width direction and that extend substantially along the curved portion (8) in a region straddling the curved portion (8) between the pair of frame plate members (20i, 20o). 22) is sandwiched and arranged.

  In the vehicle body frame structure according to the present invention, a pair of frame plate members (20i, 20o) having a substantially hat-shaped cross section are joined to each other from the left and right in the vehicle width direction to form the main frame (6L). The rigidity and strength in the vertical direction of the entire area in the extending direction of (6L) are increased. In the curved portion (8) of the main frame (6L) where a large stress is easily applied during driving of the vehicle, the reinforcing plate (22) substantially along the curved portion (8) is between the pair of frame plate members (20i, 20o). Therefore, the vertical stress acting on the bending portion (8) can be efficiently received by the closed cross-sectional structure including the reinforcing plate (22).

The curved portion (8) is curved in the vehicle vertical direction and the vehicle width direction, and the reinforcing plate (22) is curved in the vehicle width direction substantially along the curved shape of the curved portion (8). It may be formed.
When the curved portion (8) of the main frame (6L) is curved in the vertical direction and the vehicle width direction, cross-sectional reinforcement having a load support surface that intersects the extending direction in the cross section of the curved portion (8). If it is going to arrange | position a member, since the inner surface of a curved part (8) changes intricately, a difficult assembly operation will be forced. However, when the above configuration is adopted, the reinforcing plate (22) that is curved in the vehicle width direction substantially along the curved shape of the curved portion (8) is provided between the pair of frame plate members (20i, 20o). Since it suffices to arrange it in a position straddling the bending portion (8), sufficient rigidity and strength in the vicinity of the bending portion (8) can be obtained without being forced to perform difficult assembly work.

A pair of main frames (6L, 6R) extending from the lower part of the down frame (5) toward the rear side of the vehicle body are provided on the left and right in the vehicle width direction, and at least one of the pair of main frames (6L, 6R). The reinforcing plate (22) is arranged, the curved portions (8) of the pair of main frames (6L, 6R) are connected to each other by a cross pipe (10), and the cross pipe (10) In the curved portion (8) of the main frame (6L) on which the plate (22) is arranged, the frame plate member (20i, 20o) inside and outside in the vehicle width direction is welded while passing through the reinforcing plate (22). You may be made to do.
In this case, the cross pipe (10) can be supported with high rigidity by the frame plate members (20i, 20o) in the vehicle width direction of the main frame (6L), and the main frame (6L) and the cross pipe ( When an excessive load is input during 10), the deformation load acting between the main frame (6L) and the cross pipe (10) can also be received by the reinforcing plate (22).

The cross pipe (10) may include an engine pivot (15) that supports the engine block (P).
In this case, the load of the engine block (P) acting on the engine pivot (15) can be supported on the curved portions (8) of the left and right main frames (6L, 6R) via the cross pipe (10). In particular, since at least one curved portion (8) of the left and right main frames (6L, 6R) is disposed with the reinforcing plate (22) sandwiched between the pair of frame plate members (20i, 20o), The load of the engine block (P) can be supported by the vehicle body frame (F) with high rigidity.

The main frame (6L) is provided with a load receiving portion (24) that receives the load of the seat support member (19) at a position at least partially overlapping the reinforcing plate (22) in a side view of the vehicle. Anyway.
In this case, the load input from the seat to the seat support member (19) is directly supported by the reinforcing plate (22) of the main frame (6L) through the load receiving portion (24) and at a portion where the rigidity can be efficiently increased. become. Therefore, by adopting this configuration, the support rigidity of the seat can be increased.

  According to the present invention, since the reinforcing plate substantially along the curved portion is disposed between the pair of frame plate members in the region straddling the curved portion of the main frame, the curved portion curves toward the rear upper portion. The rigidity of the main frame having the portion can be increased efficiently.

It is a side view of the body frame concerning one embodiment of this invention. It is a top view of the body frame concerning one embodiment of this invention. It is a front view of the body frame concerning one embodiment of this invention. FIG. 3 is a rear view of the vehicle body frame according to the embodiment of the present invention. It is sectional drawing which follows the VV line | wire of FIG. 1 of the vehicle body frame which concerns on one Embodiment of this invention. FIG. 5 is a cross-sectional view taken along line VI-VI in FIG. 4 of the vehicle body frame according to the embodiment of the present invention. It is an enlarged view of the VII part of FIG. 1 of the vehicle body frame which concerns on one Embodiment of this invention. FIG. 5 is an enlarged view of a part VIII in FIG. 2 of the vehicle body frame according to the embodiment of the present invention. It is sectional drawing which follows the IX-IX line | wire of FIG. 1 of the vehicle body frame which concerns on one Embodiment of this invention. FIG. 6 is an enlarged view of a portion X in FIG. 5 of the vehicle body frame according to the embodiment of the present invention.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings used below, the arrow FR indicates the front of the vehicle, the arrow UP indicates the upper side of the vehicle, and the arrow LH indicates the left side of the vehicle.

FIG. 1 is a diagram showing a left side surface of a motorcycle 1 that employs a vehicle body frame structure according to this embodiment. In FIG. 1, the main body frame F is indicated by a solid line, and the other portions are indicated by imaginary lines. 2 is a view of the body frame F as viewed from above, and FIGS. 3 and 4 are a view of the body frame F as viewed from the front and a view as viewed from the rear.
The motorcycle 1 according to this embodiment is a scooter type motorcycle, and a step floor 3 on which a driver's feet are placed is arranged below the front side of the seat 2. The vehicle body frame F extends from the lower portion of the down frame 5 toward the rear side of the vehicle body, a head pipe 4 that rotatably supports a steering shaft (not shown), a down frame 5 that extends downward from the head pipe 4. A pair of left and right main frames 6L and 6R is provided.

  The left and right main frames 6L and 6R extend from the joint with the down frame 5 to the rear side of the vehicle body substantially along the step floor 3 and from the rear part of the floor frame part 7 to the rear upper part. And a seat rail portion 9 that extends from the bending portion 8 obliquely upward to the rear and then extends substantially horizontally toward the rear of the vehicle body. In the left and right main frames 6L, 6R, the front end of each floor frame portion 7 is joined to the lower portion of the down frame 5, while the curved portions 8 at the rear of the floor frame portion 7 are center cross pipes 10 (cross pipes). The seat rail portions 9 are connected to each other by the first rear cross pipe 11 and the second rear cross pipe 12.

  As shown in FIG. 1, a pair of left and right front forks 13L and 13R are attached to the lower part of the steering shaft held by the head pipe 4, and a steering handle 14 is attached to the upper part of the steering shaft. Front wheels Wf are rotatably supported at lower ends of the left and right front forks 13L and 13R.

An engine pivot 15 is attached to a center cross pipe 10 installed between the curved portions 8 of the left and right main frames 6L and 6R. The engine pivot 15 supports a front end portion of a power unit P (engine block) in which the engine 16 and the power transmission device 17 are integrated into a single block so as to be swingable. A rear wheel Wr is held at the rear end of the power unit P so that power can be transmitted. The motorcycle 1 employs a so-called unit swing type rear wheel support structure in which the power unit P and the rear wheel Wr are swingably supported by the vehicle body frame F. A cushion unit 18 is interposed between the rear end portion of the power unit P and the vehicle body frame F.
In the motorcycle 1 according to this embodiment, the power transmission device 17 of the power unit P is disposed on the left side of the vehicle, and the rear wheel Wr is cantilevered by the power transmission device 17 disposed on the left side of the vehicle body. Has been.

  A seat support pipe 19 (seat support member) that supports the lower part of the front portion of the seat 2 is connected between the rear regions of the curved portions 8 of the left and right main frames 6L and 6R. The seat support pipe 19 is formed in a substantially U shape, and both edge portions (lower edge portion 19a) on the opening side of the U shape are coupled to the left and right main frames 6L and 6R.

5 is a diagram showing a cross section taken along line VV in FIG. 1, and FIG. 6 is a diagram showing a cross section taken along line VI-VI in FIG. 7 is an enlarged view of the VII portion of FIG. 1, FIG. 8 is an enlarged view of the VIII portion of FIG. 2, FIG. 9 is a cross-sectional view taken along the line IX-IX of FIG. It is an enlarged view of the X section of FIG.
The left and right main frames 6L, 6R have a pair of frame plate members 20i, 20o having a substantially hat-shaped cross section, and upper flange portions 20i-f, 20of-f and lower flange portions 20i-f, 20of-f. The two are joined from the left and right in the vehicle width direction. The frame plate members 20i and 20o are made of a plate member such as a steel plate or a light alloy plate having a constant thickness, and are processed so that the longitudinal section of the entire region from the front end portion to the rear end portion is substantially hat-shaped by press molding, for example. Has been. In the pair of frame plate members 20i and 20o, the upper and lower flange portions 20i-f and 20of-f are joined to each other by spot welding or the like, so that the longitudinal section in the entire extending direction is a closed section. .

By the way, in the motorcycle 1 according to this embodiment, the power transmission device 17 of the power unit P is disposed on the left side of the vehicle body as described above, and the rear wheel Wr is supported by the power transmission device 17 in a cantilever manner. . For this reason, a large load is likely to act on the left side portion of the vehicle body on the vehicle body frame F.
As a countermeasure, the left and right main frames 6 </ b> L and 6 </ b> R are longitudinal sections of regions excluding the front region of the floor frame portion 7 joined to the lower end of the down frame 5 and the curved portion 8 that supports the center cross pipe 10. The area of is different on the left and right. Specifically, in the region excluding the front region and the curved portion 8 of the floor frame portion 7, the area of the longitudinal section of the left main frame 6L is set larger than the area of the longitudinal section of the right main frame 6R. Yes.

  A large load in the vertical direction and the horizontal direction is input to the front area of the floor frame portion 7 through the down frame 5 when the vehicle is running, and the bending of the power unit P through the center cross pipe 10 A large load accompanying the thrust from the road surface is input. For this reason, the area of the longitudinal section of the front region of the floor frame portion 7 and the curved portion 8 has a vertical cross-sectional area so that stress bias does not increase between the left side and the right side of the vehicle even when the above-described large load is input. It is set to be the same on the left and right.

  On the other hand, in the area other than the front region of the floor frame portion 7 and the curved portion 8, the area of the vertical section of the left main frame 6L is set larger than the area of the vertical section of the right main frame 6R, thereby The left main frame 6L supports the power unit P with high rigidity, and the right main frame 6R is reduced in size and weight.

  Further, as shown in FIGS. 5 and 10, contact pieces 21i that come into contact with the outer peripheral surface of the down frame 5 from the left and right are respectively attached to the front end portions of the frame plate members 20i and 20o of the main frames 6L and 6R. , 21o are extended. Each contact piece 21i, 21o is joined to the outer peripheral surface of the down frame 5 by, for example, laser welding in a state where the contact pieces 21i, 21o are in contact with the outer peripheral surface of the lower end portion of the down frame 5.

  The left and right main frames 6L and 6R have the same area on the left and right as described above, but the front area of the floor frame 7 and the area of the vertical section of the curved portion 8 are the same. At least a part (a central region in the front-rear direction) of a portion located below (see FIG. 1) is compared with the joint portion and the curved portion 8 with the down frame 5 in any of the left and right main frames 6L and 6R. The area of the longitudinal section is set small.

Here, in the motorcycle 1 according to this embodiment, the curved portions 8 of the left and right main frames 6L and 6R are curved from the rear end portion of the floor frame portion 7 toward the rear upper portion and toward the rear side. It is also curved outward in the vehicle width direction. That is, each curved portion 8 is curved upward while opening outward in the vehicle width direction from the rear end portion of the floor frame portion 7 toward the rear side.
In the curved portion 8 of the left main frame 6L, a reinforcing plate 22 is disposed between the pair of frame plate members 20i and 20o. The reinforcing plate 22 is disposed so as to straddle almost the entire area of the curved portion 8 of the left main frame 6L in the front-rear direction, and the upper and lower edges of the upper and lower flange portions 20i of the pair of frame plate members 20i and 20o. In a state of being sandwiched between -f and 20of, the upper and lower flange portions 20i-f and 20of are joined by laser welding or the like. The reinforcing plate 22 is curved in the left-right direction so as to substantially follow the curved shape of the curved portion 8 in the vehicle width direction.
In this embodiment, the reinforcing plate 22 is interposed only in the curved portion 8 of the left main frame 6L to which a relatively large load is input. Similarly, the reinforcing plate 22 is also provided in the right main frame 6R. You may make it interpose.

  Further, as shown in FIGS. 5 and 9, the reinforcing plate 22 is formed with a through hole 22 a through which the center cross pipe 10 penetrates with a predetermined gap. The left end of the center cross pipe 10 is coupled to the pair of frame plate members 20i and 20o of the left main frame 6L by laser welding or the like in a state where the left end is inserted into the through hole 22a of the reinforcing plate 22. The right end of the center cross pipe 10 is coupled to a pair of frame plate members 20i, 20o of the right main frame 6R by laser welding or the like.

  The left and right lower edge portions 19a of the seat support pipe 19 that supports the load of the seat 2 are located near the rear portions of the curved portions 8 of the left and right main frames 6L and 6R, as shown in FIGS. It is welded to the inner region in the vehicle width direction. The left and right lower edge portions 19a of the seat support pipe 19 are welded to receive load from the seat support pipe 19 in the vehicle width direction inner side regions of the curved portions 8 of the left and right main frames 6L and 6R. ing. The load receiving portion 24 of the left main frame 6L is provided at a position where at least a portion thereof overlaps the reinforcing plate 22 in the curved portion 8 in a side view of the vehicle. Therefore, the left lower edge portion 19a of the seat support pipe 19 is supported by a portion whose rigidity is increased by the reinforcing plate 22 of the left main frame 6L.

  Further, at appropriate positions inside the floor frame portion 7 of the left and right main frames 6L and 6R, load support that is substantially perpendicular to the mating surfaces of the frame plate members 20i and 20o (facing surfaces of the flange portions 20i-f and 20o-f). A cross-sectional reinforcing member 23 having a surface 23a is disposed. In the case of this embodiment, as shown in FIG. 5, two cross-sectional reinforcing members 23 are arranged in the floor frame portion 7 of the left main frame 6L so as to be spaced apart from each other in the extending direction. One cross-sectional reinforcing member 23 is disposed in the floor frame portion 7. The cross-section reinforcing member 23 has a joining flange 23 b extending on the outer periphery of the load support surface 23 a, and the joining flange 23 b is welded to the peripheral wall of the floor frame portion 7.

As described above, in the vehicle body frame structure according to this embodiment, the pair of frame plate members 20i and 20o having a substantially hat-shaped cross section are joined to each other from the left and right in the vehicle width direction to form the main frames 6L and 6R. Therefore, the vertical rigidity and strength of the entire region in the extending direction of the main frames 6L and 6R can be increased. In particular, in the case of this body frame structure, in the curved portion 8 of the left main frame 6L where a large stress is likely to act when the vehicle is operated, the reinforcing plate 22 substantially along the curved portion 8 is a pair of frame plate members 20i, 20o. Since they are sandwiched between them, the vertical stress acting on the curved portion 8 of the left main frame 6L can be efficiently received by the closed cross-sectional structure including the reinforcing plate 22. Therefore, by adopting this structure, it is possible to efficiently increase the rigidity of the main frame 6L having the curved portion 8 that curves toward the rear upper portion.
In this embodiment, the reinforcing plate 22 is provided only on the curved portion 8 of the left main frame 6L. However, the reinforcing plate 22 is similarly provided on the curved portion 8 of the right main frame 6R. In this case, the rigidity of the right main frame 6R can be increased efficiently as well.

  In the vehicle body frame structure according to this embodiment, the curved portions 8 of the main frames 6L and 6R are formed to bend in the vehicle vertical direction and the vehicle width direction, and are disposed on the curved portion 8 of the left main frame 6L. The reinforcing plate 22 is curved in the vehicle width direction substantially along the curved shape of the curved portion 8. For this reason, the reinforcing plate 22 is simply disposed between the pair of frame plate members 20i, 20o of the bending portion 8 in spite of the complicated shape in which the bending portion 8 is three-dimensionally bent vertically and horizontally. The rigidity and strength in the vicinity of the curved portion 8 can be sufficiently increased. Therefore, when this structure is adopted, a difficult assembling work is not forced as in the case where the cross-section reinforcing member having the load supporting surface intersecting with the extending direction is arranged in the curved portion 8.

  Furthermore, in the vehicle body frame structure according to this embodiment, the left end of the center cross pipe 10 that connects the curved portions 8 of the left and right main frames 6L and 6R penetrates the reinforcing plate 22 in the curved portion 8. In this state, it is welded to the frame plate members 20i and 20o inside and outside in the vehicle width direction. Therefore, the left end portion of the center cross pipe 10 can be supported with high rigidity on the curved portion 8 of the left main frame 6L which is reinforced by the reinforcing plate 22 and has increased rigidity. In addition, when an excessive load is input between the left main frame 6L and the center cross pipe 10, the reinforcing plate 22 abuts against the center cross pipe 10 so that the space between the main frame 6L and the center cross pipe 10 is increased. A deformation load acting on the reinforcing plate 22 can be received.

  In the vehicle body frame structure according to this embodiment, an engine pivot 15 that supports the power unit P in a swingable manner is provided on the center cross pipe 10 that connects the curved portions 8 of the left and right main frames 6L and 6R. . Therefore, a large load input from the power unit P to the center cross pipe 10 when the vehicle is traveling can be supported with high rigidity by the curved portions 8 of the left and right main frames 6L and 6R. In particular, in the case of the vehicle body frame structure according to this embodiment, the input load from the power unit P whose center of gravity is biased to the left side of the vehicle is reliably received by the curved portion 8 of the left main frame 6L reinforced by the reinforcing plate 22. Can do.

  In the vehicle body frame structure according to this embodiment, the load receiving portion 24 of the left main frame 6L that receives a load from the lower edge portion 19a of the seat support pipe 19 is at least partially a reinforcing plate in a side view of the vehicle. 19 is arranged at a position overlapping with 19. For this reason, when this structure is adopted, the load input from the seat 2 to the seat support pipe 19 can be directly supported by a portion whose rigidity can be increased by the reinforcing plate 22 of the left main frame 6L. Therefore, with this structure, the support rigidity of the seat 2 can be increased.

  In addition, this invention is not limited to said embodiment, A various design change is possible in the range which does not deviate from the summary.

DESCRIPTION OF SYMBOLS 1 ... Motorcycle 3 ... Step floor 4 ... Head pipe 5 ... Down frame 6L, 6R ... Main frame 7 ... Floor frame part 8 ... Curve part 9 ... Seat rail part 10 ... Center cross pipe (cross pipe)
15 ... Engine pivot 19 ... Seat support pipe (seat support member)
20i, 20o ... Frame plate member 20i-f, 20i-o ... Flange portion 22 ... Reinforcement plate 23 ... Cross-section reinforcement member 24 ... Load receiving portion F ... Body frame P ... Power unit (engine block)

Claims (5)

A head pipe (4) that supports the front wheels to be steerable;
A down frame (5) extending downward from the head pipe (4);
A main frame (6L) extending from the lower part of the down frame (5) toward the rear side of the vehicle body,
The main frame (6L) extends from the down frame (5) to the rear of the vehicle body substantially along the step floor (3) of the vehicle body, and the floor frame portion (7) A vehicle body frame structure of a motorcycle having a curved portion (8) curved from the rear portion toward the upper rear portion;
In the main frame (6L), a pair of frame plate members (20i, 20o) having a substantially hat-shaped cross section are joined from the left and right in the vehicle width direction between the flange portions (20i-f, 20of). A reinforcing plate (22) substantially along the curved portion (8) is sandwiched and disposed in a region straddling the curved portion (8) between the pair of frame plate members (20i, 20o). The body frame structure of a motorcycle. The curved portion (8) is formed to bend in the vehicle vertical direction and the vehicle width direction,
The body frame structure for a motorcycle according to claim 1, wherein the reinforcing plate (22) is formed to be curved in the vehicle width direction substantially along the curved shape of the curved portion (8). A pair of main frames (6L, 6R) extending from the lower part of the down frame (5) toward the rear side of the vehicle body are provided on the left and right in the vehicle width direction, and at least one of the pair of main frames (6L, 6R). The reinforcing plate (22) is disposed;
The curved portions (8) of the pair of main frames (6L, 6R) are connected to each other by a cross pipe (10),
The cross pipe (10) is formed in the curved portion (8) of the main frame (6L) on which the reinforcing plate (22) is disposed, and the cross pipe (10) passes through the reinforcing plate (22) in the vehicle width direction inside and outside. The body frame structure for a motorcycle according to claim 1 or 2, wherein the body frame structure is welded to the frame plate member (20i, 20o).   The body frame structure for a motorcycle according to claim 3, wherein the cross pipe (10) includes an engine pivot (15) for supporting the engine block (P).   The main frame (6L) is provided with a load receiving portion (24) that receives the load of the seat support member (19) at a position at least partially overlapping the reinforcing plate (22) in a side view of the vehicle. The motorcycle body frame structure according to any one of claims 1 to 4, wherein the motorcycle has a vehicle body frame structure.

Images