JP7606532B2 - Body frame of saddle-type vehicle - Google Patents

Description

The present invention relates to a body frame for a saddle-type vehicle.

Conventionally, a saddle-type vehicle has been known that includes a head pipe, a main frame extending downward from the head pipe, a lower frame extending rearward from the main frame, and a rear frame extending upward and rearward from the lower frame (see, for example, Patent Document 1).
In Patent Document 1, a reinforcing plate serving as a gusset is provided on the lower surface of the rear frame to improve the rigidity of the rear frame.

Japanese Unexamined Patent Publication No. 180578/1983

In the body frame of a saddle-ride type vehicle, it is desirable to efficiently improve the rigidity of the body frame by using gussets.
The present invention has been made in consideration of the above-mentioned circumstances, and has an object to make it possible to efficiently improve the rigidity of a body frame of a saddle-ride type vehicle by using gussets.

This specification includes the entire contents of Japanese patent application No. 2020-187414, filed on November 10, 2020.
The body frame of a saddle-ride type vehicle comprises a head pipe, a main frame extending downward from the head pipe, a lower frame extending rearward from the main frame, and a rear frame extending rearward and upward from the lower frame, the rear frame comprising an upward extension portion extending upward from the lower frame and a rearward extension portion extending rearward from an upper portion of the upward extension portion, and a gusset is provided at the rear of the upward extension portion, the body frame of a saddle-ride type vehicle is characterized in that the lower frame comprises an extension portion extending rearward beyond the connection portion between the lower frame and the upward extension portion, the gusset extends vertically along the rear portion, a lower end of the gusset is connected to the extension portion, and an upper end of the gusset is connected to the rear extension portion.

In the above-described configuration, the lower frame may be a pipe member extending in the front-rear direction, and the extension portion may be a portion of the pipe member that extends rearward beyond the connection portion.
In addition, in the above-mentioned configuration, the lower edge of the lower end of the gusset extends in the front-to-rear direction, the gusset has a protrusion that protrudes downward from the rear end of the lower edge, and the lower edge and the protrusion of the gusset may be welded to the side of the extension portion.

Furthermore, in the above-described configuration, the lower edge may be located above an axis of the lower frame in a side view of the vehicle, and the protrusion may extend downward at least to the position of the axis in a side view of the vehicle.
In addition, in the above-mentioned configuration, the gusset may include a pair of left and right side walls extending up and down along the rear portion, and a rear wall connecting the rear ends of the left and right side walls in the vehicle width direction, wherein the front edges of the side walls are connected to the rear portion, the lower end of the gusset is joined to the extension portion via the lower edges of the side walls, and the upper end of the gusset is joined to the rear extension portion via the upper edges of the side walls.

In the above-described configuration, a link member that supports the power unit so that the power unit can swing may be connected to the gusset so that the link member can swing freely.
In the above-described configuration, the gusset may be provided with a stopper portion that abuts against the link member to restrict the swing range of the link member.

In addition, in the above-mentioned configuration, a pillion step for a passenger may be provided on the gusset.

The body frame of a saddle-ride type vehicle includes a head pipe, a main frame extending downward from the head pipe, a lower frame extending rearward from the main frame, and a rear frame extending rearward and upward from the lower frame, the rear frame including an upward extension portion extending upward from the lower frame and a rearward extension portion extending rearward from an upper portion of the upward extension portion, a gusset being provided at the rear of the upward extension portion, the lower frame including an extension portion extending rearward beyond the connection portion between the lower frame and the upward extension portion, the gusset extending vertically along the rear portion, a lower end of the gusset being connected to the extension portion, and an upper end of the gusset being connected to the rearward extension portion.
With this configuration, the extension portion of the lower frame and the rearward extending portion of the rear frame are connected by a gusset provided at the rear of the upward extending portion of the rear frame, thereby efficiently improving the rigidity of the vehicle body frame.

Also, in the above-described configuration, the lower frame may be a pipe member extending in the front-rear direction, and the extension portion may be a portion of the pipe member that extends rearward beyond the connection portion.
According to this configuration, since the extension portion is a portion where the lower frame, which is a pipe material, extends rearward beyond the connection portion, the extension portion can be provided with a simple structure, thereby improving the rigidity of the vehicle body frame with a simple structure.
In addition, in the above-described configuration, the lower edge of the lower end of the gusset extends in the front-to-rear direction, the gusset has a protrusion that protrudes downward from the rear end of the lower edge, and the lower edge and protrusion of the gusset are welded to the side of the extension portion.
According to this configuration, in addition to the lower edge of the gusset, a protrusion that protrudes downward from the rear end of the lower edge is welded to the side of the extension, thereby effectively alleviating stress concentration at the weld between the gusset and the extension.

Furthermore, in the above-described configuration, the lower edge may be located above an axis of the lower frame in a side view of the vehicle, and the protruding portion may extend downward at least to the position of the axis in a side view of the vehicle.
According to this configuration, since the protruding portion extends downward at least to the position of the axis of the lower frame, the protruding portion can be provided over a wide range both vertically, and stress concentration can be effectively alleviated.
In addition, in the above-mentioned configuration, the gusset may include a pair of left and right side walls extending up and down along the rear portion, and a rear wall connecting the rear ends of the left and right side walls in the vehicle width direction, and the lower end of the gusset may be joined to the extension portion via the lower edge of the side wall, and the upper end of the gusset may be joined to the rear extension portion via the upper edge of the side wall.
According to this configuration, the gusset has a pair of left and right side walls and a rear wall, which increases the rigidity of the gusset, thereby making it possible to effectively improve the rigidity of the vehicle body frame by the gusset.

In the above-described configuration, the link member that supports the power unit so that it can swing may be connected to the gusset so that it can swing freely.
According to this configuration, the link member can be connected to the vehicle body frame with a simple structure that utilizes a gusset.
In the above-described configuration, the gusset may be provided with a stopper portion that abuts against the link member to restrict the swing range of the link member.
According to this configuration, the stopper portion that restricts the swing range of the link member can be provided with a simple structure that utilizes the gusset.

In the above-mentioned configuration, a pillion step for a passenger may be provided on the gusset.
According to this configuration, the pillion step for the passenger can be provided with a simple structure that utilizes the gusset.

FIG. 1 is a left side view of a motorcycle according to an embodiment of the present invention. FIG. 2 is a left side view of the motorcycle with the body cover and the like removed to expose the body frame. FIG. 3 is a front view of the body frame as seen from the front. FIG. 4 is a left side view of a portion of the body frame where the gusset is provided. FIG. 5 is a perspective view of a portion of the body frame where the gusset is provided, as viewed from the rear side. FIG. 6 is a left side view of the left gusset. FIG. 7 is a view of the left gusset as seen from the front side. FIG. 8 is a cross-sectional view taken along line VIII-VIII of FIG. FIG. 9 is a view of the link member as viewed from the front side.

An embodiment of the present invention will be described below with reference to the drawings. In the description, directions such as front, back, left, right, up and down are the same as directions relative to the vehicle body unless otherwise specified. Also, the symbol FR in each drawing indicates the front of the vehicle body, the symbol UP indicates the upper part of the vehicle body, and the symbol LH indicates the left side of the vehicle body.

FIG. 1 is a left side view of a motorcycle 1 according to an embodiment of the present invention.
The motorcycle 1 is a scooter-type saddle-ride vehicle including a body frame 10, a front fork 11 supporting a front wheel 2 so as to be steerable, a power unit 12 supported at the rear of the body frame 10, a rear wheel 3, and a seat 13 on which a rider sits astride.
The motorcycle 1 is provided with a body cover 14 that covers the body, including the body frame 10 .

Fig. 2 is a left side view of the motorcycle 1 with the body cover 14 and the like removed to expose the body frame 10. Fig. 3 is a front view of the body frame 10 as viewed from the front.
The body frame 10 includes a head pipe 15 provided at the front end of the body frame 10, a front gusset 16 connected to the rear surface of the head pipe 15, and a pair of left and right main frames 17 extending downward from the front gusset 16. The front gusset 16 may be considered as part of the main frames 17.
The vehicle body frame 10 also includes a pair of left and right lower frames 18 extending rearward from the lower ends of the main frames 17, and a pair of left and right rear frames 19 extending rearward and upward from the rear ends of the lower frames 18.
More specifically, each rear frame 19 includes an upward extension 19a extending upward from the rear end of the lower frame 18, and a rear extension 19b extending rearward from an upper portion of the upward extension 19a. Both the upward extension 19a and the rear extension 19b are inclined upward toward the rear, but the rear extension 19b is closer to horizontal than the upward extension 19a.
Furthermore, the body frame 10 is equipped with a gusset 20 provided on the upward extension portion 19 a of the rear frame 19 .

The body frame also includes a first cross member 21a that connects the left and right main frames 17 in the vehicle width direction (left-right direction) below the front gusset 16, a second cross member 21b that connects the left and right main frames 17 in the vehicle width direction below the first cross member 21a, a third cross member 21c that connects the left and right lower frames 18 in the vehicle width direction, a fourth cross member 21d that connects the front portions of the left and right rear frames 19 in the vehicle width direction, and a fifth cross member 21e that connects the rear portions of the left and right rear frames 19 in the vehicle width direction.

The front fork 11 is supported by a head pipe 15 so as to be steerable left and right.
The front fork 11 comprises a steering shaft (not shown) supported rotatably on the head pipe 15, a bridge member 22 fixed to the lower end of the steering shaft, and a pair of left and right fork tubes 23 supported by the bridge member 22 and extending downward from the bridge member 22.
The front wheel 2 is supported by an axle 2 a that spans between the lower ends of the left and right fork tubes 23 .
A steering handle 24 is attached to the upper end of the front fork 11 .

The power unit 12 extends below the rear frame 19 in the front-rear direction of the vehicle.
The power unit 12 is a unit swing engine in which an arm portion 30 that supports the rear wheel 3 so that it can swing freely and an engine 31 that drives the rear wheel 3 are integrally provided.
The engine 31 is an internal combustion engine. The engine 31 includes a crankcase portion 32 that houses a crankshaft (not shown), and a cylinder portion 33 that extends forward from the front surface of the crankcase portion 32. A piston (not shown) connected to the crankshaft reciprocates within the cylinder portion 33. The cylinder portion 33 extends forward of the rear frame 19 from the crankcase portion 32, passing between the front portions of the left and right rear frames 19.

The arm portion 30 extends rearward from one side surface (left side) of the crankcase portion 32 in the left-right direction.
The rear wheel 3 is supported by an axle 3 a provided at the rear end of the arm portion 30 .
The arm portion 30 is offset to the left with respect to the rear wheel 3, which is located in the center of the vehicle width. That is, the arm portion 30 extends rearward from the crankcase portion 32, passing to the left of the rear wheel 3.

The arm portion 30 is formed to be hollow. A continuously variable transmission (not shown) using a pulley and a V-belt is housed inside the arm portion 30. The driving force of the engine 31 is transmitted to the rear wheel 3 via the continuously variable transmission.
An air cleaner box 35 is attached to the upper surface of the arm portion 30. Outside air taken in by the air cleaner box 35 is purified by the air cleaner box 35 and then supplied to the engine 31.

The motorcycle 1 includes a link member 38 (FIG. 2) that connects the power unit 12 to the rear portion of the body frame 10 so as to be able to swing freely.
The link member 38 is connected to the gusset 20 of the body frame 10 via a first pivot shaft 39 that extends in the vehicle width direction.
Additionally, the link member 38 is connected to an upper portion of the crankcase portion 32 via a second pivot shaft 40 that extends in the vehicle width direction.
The power unit 12 swings up and down around a first swing shaft 39 and a second swing shaft 40 of the link member 38 .
A rear cushion 41 is suspended between the rear end of the arm portion 30 and the rear end of the body frame 10 .

Referring to FIG. 1, the seat 13 is disposed along the rear extension 19b of the rear frame 19 and is supported from below by the rear extension 19b.
A step floor 42 on which a driver seated in the front part of the seat 13 places his/her feet is located below and in front of the seat 13 and is supported from below by the lower frame 18.
A passenger sits at the rear of the seat 13. A pair of left and right pillion steps 43 on which the passenger places his/her feet are provided on the gusset 20.

The body cover 14 includes an upper cover 44 that covers the handlebars 24, a front cover 45 that covers the front part of the body frame 10, such as the head pipe 15, from the front, an inner cover 46 that covers the front part of the body frame 10, such as the head pipe 15, from the rear, a lower cover 47 that covers the lower frame 18 from the side, and a rear side cover 48 that covers the body below the seat 13 from the side.
The front fender 49 is attached to the front fork 11 .

2 , the left main frame 17 and the left lower frame 18 are integrally formed by bending a single continuous pipe member 25 at its longitudinal midsection. That is, the left main frame 17 and the left lower frame 18 are made of a single pipe member 25.
Similarly, the right side main frame 17 and the right side lower frame 18 each are formed of a single pipe member 25. Since the main frame 17 and the lower frame 18 form a left-right pair, two pipe members 25 are provided.
The pipe material 25 has a circular cross section.
The lower frame 18 extends linearly in the front-rear direction with a slight upward tilt to the rear in a side view of the vehicle. An axis 18a of the lower frame 18 extends linearly in the front-rear direction with a slight upward tilt to the rear in a side view of the vehicle.

Fig. 4 is a left side view of a portion of the body frame 10 where the gusset 20 is provided. Fig. 5 is a perspective view of the portion of the body frame 10 where the gusset 20 is provided, as viewed from the rear side. In Figs. 4 and 5, the link member 38 is also shown.
2, 4, and 5, each of the left and right rear frames 19 is formed by bending a continuous pipe material 50 at a longitudinal center portion thereof. That is, the upward extension portion 19a and the rearward extension portion 19b are formed by bending the pipe material 50.
The pipe material 50 of the rear frame 19 has a circular cross section. The thickness of the pipe material 50 constituting the rear frame 19 is smaller than the thickness of the pipe materials constituting the main frame 17 and the lower frame 18.

The upward extension portion 19a of the rear frame 19 extends rearward and upward from the rear end portion of the lower frame 18 in a position closer to vertical than horizontal.
A lower end 51 of the upward extension 19 a is bent forward so as to fit along the upper surface of the lower frame 18 .
The lower end portion 51 has a semicircular shape formed by cutting out the lower half of the pipe material 50 at the lower end portion 51 when viewed in the axial direction.

In a side view of the vehicle, lower edges 51a, 51b of the lower end portion 51 extend in the front-rear direction along the axis 18a of the lower frame 18. The lower edges 51a, 51b are lower edges of the semicircular portion and are provided as a pair spaced apart from each other in the vehicle width direction.
The lower edges 51 a, 51 b are located above the axis 18 a of the lower frame 18 in a side view of the vehicle. That is, the lower edges 51 a, 51 b are connected to the upper part of the lower frame 18.
The upward extension 19a is joined to the lower frame 18 by a weld bead 52 that extends in the front-rear direction along the lower edges 51a, 51b.
In detail, one lower edge 51a is joined to the outer surface of the upper part of the lower frame 18 in the vehicle width direction, and the other lower edge 51b is joined to the inner surface of the upper part of the lower frame 18 in the vehicle width direction.

The rear extension portion 19b of the rear frame 19 extends rearward from the upper end of the upward extension portion 19a in a position closer to horizontal than vertical.
The rearward extending portion 19b includes a bent portion 55 that is bent rearward in an arc shape from the upper end of the upward extending portion 19a, and a main body portion 56 that extends rearward and upward from the rear end of the bent portion 55.

The lower end 51 of the upward extension 19a is a connection portion 57 that connects the lower frame 18 and the upward extension 19a.
The lower frame 18 has an extension portion 18 b that extends rearward beyond the connection portion 57 .
The extension portion 18 b is a portion of the pipe material 25 constituting the lower frame 18 that extends rearward beyond the connection portion 57 .

The gussets 20 are provided at the rear portions 60 of the left and right upward extension portions 19a.
The gusset 20 extends vertically in a rearwardly inclined position along the rear portion 60. A lower end portion 20a of the gusset 20 is connected to an extension portion 18b of the lower frame 18. An upper end portion 20b of the gusset 20 is connected to a rear extension portion 19b of the rear frame 19.
That is, the gusset 20 vertically connects the extension portion 18b and the rear extension portion 19b.

Fig. 6 is a left side view of the left gusset 20. Fig. 7 is a view of the left gusset 20 as seen from the front side. Fig. 8 is a cross-sectional view taken along line VIII-VIII in Fig. 4. Note that since the left and right gussets 20 are substantially symmetrical, the following description will be given mainly with reference to the left gusset 20.
4 to 8, the gusset 20 includes a pair of left and right side walls 61, 62 extending vertically along the rear portion 60 of the upward extension portion 19a, and a rear wall 63 connecting the rear ends of the side walls 61, 62 in the vehicle width direction.

The side wall 61 is an outer side wall in the vehicle width direction, and is disposed with its plate thickness oriented in the vehicle width direction.
The side wall 62 is a side wall on the inner side in the vehicle width direction, faces the side wall 61, and is disposed on the inner side in the vehicle width direction with respect to the side wall 61.
A front edge 61a of the side wall 61 and a front edge 62a of the side wall 62 extend vertically in a rearwardly inclined position along the axis 19a1 of the upward extension portion 19a in a side view of the vehicle.
The side wall 61 is joined to the outer surface of the rear portion 60 in the vehicle width direction by a weld bead 64 along a front edge 61a.
The side wall 62 is joined to the inner surface of the rear portion 60 in the vehicle width direction by a weld bead 65 (FIG. 5) along a leading edge 62a.

The rear wall 63 covers the rear portion 60 of the upward extension portion 19a from the rear. The rear wall 63 extends vertically between the extension portion 18b and the rearward extension portion 19b. The rear wall 63 extends vertically in a rearwardly inclined position along the axis 19a1 of the upward extension portion 19a in a side view of the vehicle.
In detail, the rear wall 63 includes an upper rear wall 68 provided on the upper portion of the gusset 20 and a lower rear wall 69 provided below the upper rear wall 68 .
The rear wall 63 has an opening 70 that opens rearward between the upper rear wall 68 and the lower rear wall 69 .
The upper rear wall 68 has an upper cutout portion 68a formed by cutting out an upper portion of the upper rear wall 68 so as to fit along the underside of the rear extension portion 19b.
The lower rear wall 69 has a lower cutout 69a formed by cutting out the lower portion of the lower rear wall 69 so as to fit along the upper surface of the extension 18b.

The side walls 61 and 62 extend vertically between the extension portion 18b and the rear extension portion 19b.
An upper edge 61b of the side wall 61 and an upper edge 62b of the side wall 62 extend rearward and upward along an axis 19b1 of the rearward extending portion 19b in a side view of the vehicle.
An upper edge 61b of the side wall 61 is joined to the lower surface of the bent portion 55 and the lower surface of the main body portion 56 by a weld bead 71 along the upper edge 61b.
An upper edge 62b of the side wall 62 is joined to the lower surface of the bent portion 55 and the lower surface of the body portion 56 by a weld bead 72 (FIG. 5) along the upper edge 62b.
That is, the upper end portion 20b of the gusset 20 is joined to the underside of the front end portion of the rear extension portion 19b via the upper edges 61b and 62b.

A lower edge 61c of the side wall 61 and a lower edge 62c of the side wall 62 (FIG. 5) extend in the front-rear direction along the axis 18a of the lower frame 18 in a side view of the vehicle. The lower edges 61c and 62c are located above the axis 18a of the lower frame 18 in a side view of the vehicle. The lower edges 61c and 62c are lower edges of the lower end portions 20a of the gussets 20.
The side wall 61 further includes a protruding portion 61d that protrudes downward from the rear end of the lower edge 61c. The protruding portion 61d is inclined rearward so as to be aligned with the axis 19a1 of the upward extension portion 19a in a side view of the vehicle.
In a side view of the vehicle, the protrusion 61d extends from the lower edge 61c to a position below the axis 18a, straddling the axis 18a of the lower frame 18. The protrusion 61d extends downward at least to the position of the axis 18a in a side view of the vehicle.

The side wall 62 includes a protruding portion 62d that protrudes downward from the rear end of the lower edge 62c. The protruding portion 62d is inclined rearward so as to be aligned with the axis 19a1 of the upward extension portion 19a in a side view of the vehicle.
In a side view of the vehicle, the protruding portion 62d extends from the lower edge 62c to a position below the axis 18a, straddling the axis 18a of the lower frame 18. The protruding portion 62d extends downward at least to the position of the axis 18a in a side view of the vehicle.

The side wall 61 is joined to the vehicle width direction outer side surface of the extension portion 18b of the lower frame 18 by a weld bead 73 along the lower edge 61c and the front edge of the protrusion 61d.
The side wall 62 is joined to the inner side surface in the vehicle width direction of the extension portion 18b of the lower frame 18 by a weld bead 74 (FIG. 5) along the lower edge 62c and the front edge of the protrusion 62d.

5 and 8, the lower portion of the peripheral edge of the lower cutout portion 69a of the rear wall 63 of the gusset 20 covers part of the rear end surface of the extension portion 18b from the rear.
The upper end of the lower cutout portion 69a is spaced upward from the upper portion of the rear end surface of the extension portion 18b. The lower end of the internal space of the gusset 20 communicates with the outside at the rear from the lower cutout portion 69a.

4 and 6, the side wall 61 is provided with a hole 76 .
The pillion step 43 includes a step stay 43a attached to the side wall 61 and a step 43b (FIG. 1) supported by the step stay 43a.
The step stay 43a is rod-shaped and extends rearward from the side wall 61. The step stay 43a is inserted into the hole 76 and joined to the side wall 61.

The gusset 20 includes a link connection portion 77 to which the link member 38 is connected. The link connection portion 77 is a hole that penetrates the side wall 61 and the side wall 62 in the vehicle width direction. The link connection portion 77 is provided above the step stay 43a.
The link member 38 is connected to the gusset 20 via a first pivot shaft 39 (FIG. 2) that is inserted into the link connection portion 77. A pair of left and right first pivot shafts 39 are provided and attached to the left and right gussets 20, respectively.

FIG. 9 is a view of the link member 38 as viewed from the front side.
2, 4, 5 and 9, the link member 38 has a first connection portion 81a connected to the left gusset 20 via the first pivot shaft 39 (FIG. 2), and a first connection portion 81b connected to the right gusset 20 via the first pivot shaft 39.
The link member 38 also includes a rod-shaped left-right connecting member 82 that connects the first connection portion 81a on one side (left side) and the first connection portion 81b on the other side (right side) in the left-right direction, and a second connection portion 83 that is connected to the upper portion of the crankcase portion 32.

The front portion of the first connection portion 81 a is inserted into the internal space of the left gusset 20 through the opening 70 of the gusset 20 and is supported by the first pivot shaft 39 .
The front portion of the first connection portion 81 b is inserted into the internal space of the right-side gusset 20 through the opening 70 of the gusset 20 and is supported by the first pivot shaft 39 .

One end of the left-right connecting member 82 is connected to the rear portion of the left first connecting portion 81a, and the other end of the left-right connecting member 82 is connected to the rear portion of the right first connecting portion 81b.
The second connection portion 83 is a cylindrical member extending in the vehicle width direction. The second connection portion 83 is disposed at a position between the first connection portions 81a and 81b in the vehicle width direction, and is joined to the lower surfaces of the left and right connection members 82. The second connection portion 83 is disposed below the first connection portions 81a and 81b.
The link member 38 is connected to the crankcase portion 32 by a second pivot shaft 40 ( FIG. 2 ) that is inserted through an upper portion of the crankcase portion 32 and into the cylindrical interior of the second connection portion 83 .

Furthermore, the link member 38 includes an arm member 84 that extends upward and downward from the rear portion of the left first connection portion 81a.
The arm member 84 is disposed directly behind the rear wall 63 of the left gusset 20. An upper end of the arm member 84 is provided with an upper abutment portion 84a that faces the upper rear wall 68 from behind. A lower end of the arm member 84 is provided with a lower abutment portion 84b that faces the lower rear wall 69 from behind.

The link member 38 swings about a first swing shaft 39 in association with the swing of the power unit 12 .
The swing range of the link member 38 is restricted by the arm member 84, which swings integrally with the first connection portion 81a, abutting from behind against the rear wall 63 of the gusset 20. In other words, the rear wall 63 is a stopper portion that abuts against the link member 38 to restrict the swing range of the link member 38.
In detail, when the power unit 12 is swung to the upper limit position, the upper contact portion 84a comes into contact with the upper rear wall 68. When the power unit 12 is swung to the lower limit position, the lower contact portion 84b comes into contact with the lower rear wall 69.

4 and 5, in the body frame 10, the extension portion 18b of the lower frame 18 and the rearward extending portion 19b of the rear frame 19 are connected vertically by the gussets 20, so that the rigidity of the body frame 10 can be efficiently improved. Therefore, even if the thickness of the pipe material 50 constituting the rear frame 19 is made smaller than the thickness of the pipe material 25 constituting the main frame 17 and the lower frame 18 to reduce weight, the rigidity of the rear frame 19 can be increased. Also, although the weight of the portion where the gussets 20 are provided increases, the gussets 20 are located toward the center of the motorcycle 1 in the vehicle fore-aft direction, so that the effect of the increased weight on the riding performance of the motorcycle 1 can be reduced.
In addition, the lower end 20a of the gusset 20 is connected to the upper part of the rear extension 19b, and does not extend below the rear extension 19b. Therefore, the gusset 20 can be provided compactly in the vertical direction compared to a configuration in which the gusset is provided up to the lower end face of the lower frame.

As described above, according to the embodiment to which the present invention is applied, the body frame 10 of the motorcycle 1 includes the head pipe 15, the main frame 17 extending downward from the head pipe 15, the lower frame 18 extending rearward from the main frame 17, and the rear frame 19 extending rearward and upward from the lower frame 18. The rear frame 19 includes an upward extension portion 19a extending upward from the lower frame 18, and a rear frame 19b extending rearward from the upper frame 19. a, and a rearward extending portion 19b extending rearward from the upper portion of the upper frame 18. A gusset 20 is provided at a rear portion 60 of the upper extending portion 19a. The lower frame 18 has an extension portion 18b extending rearward beyond a connection portion 57 between the lower frame 18 and the upper extending portion 19a. The gusset 20 extends vertically along the rear portion 60. The lower end portion 20a of the gusset 20 is connected to the extension portion 18b, and the upper end portion 20b of the gusset 20 is connected to the rearward extending portion 19b.
According to this configuration, the extension portion 18b of the lower frame 18 and the rear extension portion 19b of the rear frame 19 are connected by a gusset 20 provided at the rear portion 60 of the upward extension portion 19a of the rear frame 19, thereby efficiently improving the rigidity of the body frame 10.

The lower frame 18 is made of a pipe member 25 extending in the front-rear direction, and the extension portion 18 b is a portion of the pipe member 25 that extends rearward beyond the connection portion 57 .
According to this configuration, the extension portion 18b is a portion where the lower frame 18, which is the pipe material 25, extends rearward beyond the connection portion 57, so that the extension portion 18b can be provided with a simple structure. Therefore, the rigidity of the body frame 10 can be improved with a simple structure.
In addition, lower edges 61c, 62c of the lower end portion 20a of the gusset 20 extend in the front-to-rear direction, and the gusset 20 has protrusions 61d, 62d that protrude downward from the rear ends of the lower edges 61c, 62c, and the lower edges 61c, 62c and protrusions 61d, 62d of the gusset 20 are welded to the sides of the extension portion 18b.
According to this configuration, in addition to the lower edges 61c, 62c, the gusset 20 has protruding portions 61d, 62d protruding downward from the rear ends of the lower edges 61c, 62c welded to the side surfaces of the extension portion 18b. Therefore, stress can be distributed to the lower edges 61c, 62c and the protruding portions 61d, 62d, and stress concentration at the welded portions between the gusset 20 and the extension portion 18b can be effectively alleviated.

Furthermore, the lower edges 61c, 62c are located above the axis 18a of the lower frame 18 in a side view of the vehicle, and the protrusions 61d, 62d extend downward at least to the position of the axis 18a in a side view of the vehicle.
According to this configuration, the protrusions 61d, 62d extend downward at least to the position of the axis 18a of the lower frame 18, so that the protrusions 61d, 62d can be provided over a wide range both vertically, thereby effectively reducing stress concentration.
In addition, the gusset 20 has a pair of left and right side walls 61, 62 extending vertically along the rear portion 60, and a rear wall 63 connecting the rear ends of the left and right side walls 61, 62 in the vehicle width direction, and the lower end portion 20a of the gusset 20 is joined to the extension portion 18b via the lower edges 61c, 62c of the side walls 61, 62, and the upper end portion 20b of the gusset 20 is joined to the rear extension portion 19b via the upper edges 61b, 62b of the side walls 61, 62.
According to this configuration, the gusset 20 includes the pair of left and right side walls 61, 62 and the rear wall 63, which increases the rigidity of the gusset 20. Therefore, the rigidity of the body frame 10 can be effectively improved by the gusset 20.

In addition, a link member 38 that supports the power unit 12 so that the power unit 12 can swing is connected to the gusset 20 so that the link member 38 can swing freely.
According to this configuration, the link member 38 can be connected to the vehicle body frame 10 with a simple structure that utilizes the gusset 20.
Further, the gusset 20 is provided with a rear wall 63 as a stopper portion that abuts against the link member 38 to restrict the swing range of the link member 38 .
According to this configuration, the stopper portion that restricts the swing range of the link member 38 can be provided with a simple structure that utilizes the gusset 20.

Additionally, a pillion step 43 for a passenger is provided on the gusset 20 .
According to this configuration, the pillion step 43 for the passenger can be provided with a simple structure that utilizes the gusset 20.

The above-described embodiment shows one mode in which the present invention is applied, and the present invention is not limited to the above-described embodiment.
In the above embodiment, a motorcycle 1 has been described as an example, but the present invention is not limited to this, and the present invention is applicable to three-wheeled saddle-ride vehicles having two front or two rear wheels, and saddle-ride vehicles having four or more wheels.

1. Motorcycles (saddle-type vehicles)
REFERENCE SIGNS LIST 10 Body frame 12 Power unit 15 Head pipe 17 Main frame 18 Lower frame 18a Axis 18b Extension 19 Rear frame 19a Upper extension 19b Rear extension 20 Gusset 20a Lower end 20b Upper end 25 Pipe member 38 Link member 43 Pillion step 57 Connection 60 Rear 61, 62 Side wall 61a, 62a Front edge 61b, 62b Upper edge 61c, 62c Lower edge (Lower edge of lower end, Lower edge of side wall)
61d, 62d Protrusions 63 Rear wall (stopper portion)

Claims (6)

A body frame for a saddle-ride type vehicle comprising: a head pipe (15), a main frame (17) extending downward from the head pipe (15), a lower frame (18) extending rearward from the main frame (17), and a rear frame (19) extending rearward and upward from the lower frame (18), the rear frame (19) comprising an upward extension portion (19a) extending upward from the lower frame (18) and a rearward extension portion (19b) extending rearward from an upper portion of the upward extension portion (19a), and a gusset (20) provided at a rear portion (60) of the upward extension portion (19a),
the lower frame (18) includes an extension portion (18b) extending rearward beyond a connection portion (57) between the lower frame (18) and the upward extension portion (19a);
The gusset (20) extends vertically along the rear portion (60), a lower end (20a) of the gusset (20) is connected to the extension portion (18b), and an upper end (20b) of the gusset (20) is connected to the rear extension portion (19b);
the lower frame (18) is a pipe member (25) extending in the front-rear direction, and the extension portion (18b) is a portion of the pipe member (25) that extends rearward beyond the connection portion (57);
A link member (38) that swingably supports the power unit (12) is swingably connected to the gusset (20),
A vehicle body frame for a saddle-ride type vehicle , characterized in that a rear wall (63) serving as a stopper that abuts against the link member (38) to restrict the swing range of the link member (38) is provided on the gusset (20) . A lower edge (61c, 62c) of the lower end portion (20a) of the gusset (20) extends in the front-rear direction, and the gusset (20) includes a protruding portion (61d, 62d) protruding downward from a rear end of the lower edge (61c, 62c),
2. The body frame of a saddle-type vehicle according to claim 1, wherein the lower edge (61c, 62c) and the protruding portion (61d, 62d) of the gusset (20) are welded to a side surface of the extension portion (18b). The body frame of a saddle-type vehicle according to claim 2, characterized in that the lower edge (61c, 62c) is located above the axis (18a) of the lower frame (18) in a side view of the vehicle, and the protrusion (61d, 62d) extends downward at least to the position of the axis (18a) in a side view of the vehicle. The gusset (20) includes a pair of left and right side walls (61, 62) extending vertically along the rear portion (60), and the rear wall (63) connecting rear ends of the left and right side walls (61, 62) in the vehicle width direction,
The front edges (61a, 62a) of the side walls (61, 62) are connected to the rear part (60);
4. The body frame of a saddle-type vehicle according to claim 1, wherein the lower end portion (20a) of the gusset (20) is joined to the extension portion (18b) via the lower edge (61c, 62c) of the side wall (61, 62), and the upper end portion (20b) of the gusset (20) is joined to the rear extension portion (19b) via the upper edge (61b, 62b) of the side wall (61, 62). The rear wall (63) of the gusset (20) includes an opening (70) that opens rearward of the gusset (20), and an upper rear wall (68) and a lower rear wall (69) provided above and below the opening (70),
The link member (38) has a connection portion (81) and an arm member (84) extending upward and downward from a rear portion of the connection portion (81),
The connection portion (81) is inserted into the internal space of the gusset (20) through the opening (70) and supported so as to be capable of swinging,
5. The body frame for a saddle-ride type vehicle according to claim 1, wherein the arm members (84) face the upper rear wall (68) and the lower rear wall (69) from the rear. 6. The body frame for a saddle-ride type vehicle according to claim 1, wherein a pillion step (43) for a passenger is provided on the gusset (20).

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