JP3701716B2 - Motorcycle - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a motorcycle in which an engine is configured as a part of a body frame.
[0002]
[Prior art]
Conventionally, there is a so-called diamond frame as a body frame of this type of motorcycle. This diamond-shaped frame is connected to the main pipe that extends downward from the head pipe through the upper part of the engine, and a down tube that extends toward the lower part of the front side of the engine body. The rear arm bracket and the down tube are connected by an engine.
[0003]
A rear arm is connected to the rear arm bracket so as to be swingable in the vertical direction via a pivot shaft. A cushion unit is interposed between the rear arm and the upper part of the main frame or the rear arm bracket.
[0004]
The diamond frame constructed in this way has the advantage that the length of the down tube is shorter and lighter than when the dow tube is extended to the rear side of the vehicle body under the engine and connected to the rear arm bracket. .
[0005]
[Problems to be solved by the invention]
However, as described above, even in the case of a diamond-type frame in which the down tube may be short, it is required to further reduce the number of frame constituent members in order to reduce the weight and reduce the cost.
[0006]
The present invention has been made to solve such problems. In adopting a configuration in which the engine is used as a part of a vehicle body frame, the number of frame components is reduced as much as possible to reduce weight and cost. For the purpose.
[0007]
[Means for Solving the Problems]
The motorcycle according to the first aspect of the present invention is configured such that the crankcase can be divided into an upper crankcase and a lower crankcase in the vertical direction, the main frame is extended to the upper part of the crankcase of the engine, and the rear end portion is together is attached to the upper portion of the upper crankcase, this upper crankcase to support the rear arm swingably, the upper end of the cushion unit connecting the lower end portion to the rear arm is supported on the upper crankcase, the upper crankcase A cassette-type transmission is mounted so that it can be attached to and detached from the left and right sides of the vehicle body from one side, and the side fixed to the other side of the upper crankcase at the rear end of the main frame is viewed from the side of the vehicle. It is positioned so as to overlap the ceremony mission.
Accordingly, since the rear arm can be connected to the main frame via the crankcase, the rear arm bracket and the down tube are not required as compared with the diamond type frame, and the main frame is shortened.
[0008]
The motorcycle according to the second invention is the motorcycle according to the first invention, wherein the cassette type transmission is mounted on the upper crankcase so as to be detachable from one side in the left-right direction of the vehicle body, and the rear end of the main frame The side portion fixed to the other side portion of the upper crankcase is positioned so as to overlap the cassette type transmission when viewed from the side of the vehicle body.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
First Embodiment Hereinafter, an example of an embodiment of a motorcycle according to the present invention will be described in detail with reference to FIGS.
FIG. 1 is a side view of a motorcycle according to the present invention, FIG. 2 is a side view of an essential part, FIG. 3 is a cross-sectional view taken along line III-III in FIG. 2, and FIG.
[0010]
In these drawings, reference numeral 1 denotes a motorcycle according to this embodiment. In the motorcycle 1, an engine 4 is disposed between a front wheel 2 and a rear wheel 3, and a head pipe 7 is connected to an upper crankcase 5 of the engine 4 via a main frame 6 described later. The front fork 8 is supported in a steerable manner, and the rear arm 10 is connected to the upper crankcase 5 via a pivot shaft 9 so as to be swingable in the vertical direction.
[0011]
The engine 4 is of a water-cooled 4-cycle 4-cylinder, and the upper crankcase 5 and the crankcase, in the vertical direction formed by the lower crankcase 11 for closing the lower end opening of the upper crankcase 5 The cylinder 12 is attached to the upper crankcase 5 so as to be divided. The cylinder 12 is configured such that its axis is inclined forward, and an intake device 13 is connected to a rear surface directed toward the rear upper side of the vehicle body, and an exhaust pipe 14 is connected to a front surface directed toward the lower front side. Further, a radiator 15 is disposed between the cylinder 12 and the front wheel 2. The radiator 15 is supported on the main frame 6 by a stay (not shown).
[0012]
As shown in FIGS. 1 and 2, the intake device 13 includes a throttle valve device 13a connected to an upper end of an intake pipe extending right above the cylinder 12, a fuel injection device 13b, and an upper end of the throttle valve device 13a. It consists of an air cleaner 13c that faces it. As shown in FIG. 4, the throttle valve device 13a and the fuel injection device 13b are provided for each cylinder.
[0013]
The exhaust pipe 14 is provided for each cylinder and is gathered below the engine 4. As shown in FIG. 1 and FIG. 2, an exhaust control valve device 14a is provided in this assembly portion. The exhaust control valve device 14a is for increasing the exhaust efficiency by utilizing the pressure wave of the exhaust, and has a conventionally known structure that increases or decreases the cross-sectional area of the exhaust passage for each cylinder according to the engine operating state. It has become.
[0014]
The upper crankcase 5 is structured to rotatably support the crankshaft 17 together with the lower crankcase 11, and a cassette type mission 18 is mounted on the rear part. This cassette type transmission 18 is attached to the right side of the vehicle body in the upper crankcase 5 so as to be detachable along the left-right direction of the vehicle body, and the crankshaft 17 drives the drive shaft 18a so that the driven shaft 18b The output sprocket 19 has a conventionally well-known structure. The output sprocket 19 is wound with a rear wheel drive chain indicated by reference numeral 20 in FIGS. 1 and 2.
[0015]
The lower crankcase 11 has a crank web rotation space at the inner front and an oil tank 21 at the inner rear. The engine 4 employs a so-called dry sump type lubrication device that pumps oil from the oil tank 21 to a portion to be lubricated.
[0016]
As shown in FIG. 4, the main frame 6 includes a pair of left and right tank rails 6a, 6a having a front end coupled to the head pipe 7, and a reinforcing member 6b that connects the front end portions of the tank rails 6a, 6a. And formed from. In this embodiment, the tank rail 6a is formed in the shape of a rectangular tube whose longitudinal sectional shape is a rectangle that is long in the vertical direction by an aluminum alloy. Further, the tank rail 6a is bent so that a portion above the cylinder protrudes to the side of the vehicle body by pressing. The intake device 13 faces the bent portions of the left and right tank rails 6a, 6a.
[0017]
When the four throttle valve devices 13a are arranged between the bent portions, these throttle valve devices 13a are arranged near the center in the left-right direction of the vehicle body, and the vehicle rail side of the bent portion of the tank rail 6a. The cam chain (not shown) of the engine 4 is arranged at one end in the left-right direction of the vehicle body, not between the cylinders, so that the amount of protrusion in the direction becomes as small as possible.
[0018]
As described above, the tank rails 6a, 6a formed in a rectangular tube shape are welded at the front end to the head pipe 7 and extend from the head pipe 7 so as to incline downwardly through the cylinder 12 above. The front part and the rear part of the rear end are fixed to the upper part of the upper crankcase 5 with fixing bolts 22. And the fuel tank 23 is being fixed to the upper part of these tank rails 6a and 6a, as shown in FIG.
[0019]
As shown in FIG. 4, the rear arm 10 has front arm portions 10a, 10a provided on both sides in the left-right direction of the vehicle body pivotally supported by the pivot shaft 9, and a lower front portion is provided here as shown in FIG. It is connected to the lower end portion of the cushion unit 26 via a protruding connecting member 24 and a link mechanism 25 pivotally attached to the connecting member 24. In addition, a chain hole 10b through which the rear wheel drive chain 20 is passed is provided in the lower portion of the rear arm 10.
[0020]
In the link mechanism 25, a part of a node is also pivotally attached to a bracket 11a formed integrally with the end of the lower crankcase 11 on the rear side of the vehicle body. Further, in this embodiment, as shown in FIGS. 2 and 4, the upper end portion of the cushion unit 26 is a pair of left and right cushion unit brackets fixed to the rear end portion of the upper body of the upper crankcase 5. 27 is pivotally supported.
[0021]
As shown in FIG. 3, the pivot shaft 9 is supported by a boss portion 5 a formed integrally with an end portion on the rear side of the vehicle body at the lower portion of the upper crankcase 5 so as to penetrate therethrough. Then, the front arm portions 10a and 10a of the rear arm 10 are rotatably supported via bearings 28 at portions of the pivot shaft 9 protruding from the boss portion 5a. Further, a pair of left and right footrest brackets 30 for supporting the footrest 29 (FIG. 1) is supported at the shaft end portion of the pivot shaft 9.
[0022]
As shown in FIG. 1, the footrest bracket 30 has a holding plate 29 a of a footrest 29 attached to an end portion on the rear side of the vehicle body, and is supported by the pivot shaft 9 and an end portion on the front side of the vehicle body is connected to the upper crankcase 5. And fixed to the lower crankcase 11. That is, the footrest 29 is supported by the crankcase of the engine 4 through the holding plate 29a, the footrest bracket 30, the pivot shaft 9, and the like.
[0023]
An occupant in a state of getting on the footrest 29 with his / her foot on is indicated by a symbol A in FIG. The seat on which the occupant A is seated is provided integrally with the rear cowling 31. The rear cowling 31 is supported by the upper crankcase 5 of the engine 4 via a rear cowling frame 32.
[0024]
In the motorcycle 1 configured as described above, the main frame 6 extends from the head pipe 7 to the upper portion of the upper crankcase 5 and the rear end portion is coupled to the upper crankcase 5 and is pivoted to the upper crankcase 5. The rear arm 10 is swingably supported via the shaft 9 and the upper end of the cushion unit 26 having the lower end connected to the rear arm 10 is supported by the upper crankcase 5, so that the upper crankcase is part of the vehicle body frame. Thus, the rear arm 10 can be connected to the main frame 6 via the upper crankcase 5.
[0025]
Therefore, the rear arm bracket and the down tube are not required as compared with the conventional diamond type frame, and the main frame is shortened.
[0026]
Further, the motorcycle 1 shown in this embodiment has a configuration in which the crankcase of the engine 4 can be divided in the vertical direction. The upper crankcase 4 includes a rear end portion of the main frame 6, a rear arm 10, and a cushion unit 26. Since the upper crankcase 5 is a single rigid body because the upper end is connected, the upper ends of the main frame 6, the rear arm 10 and the cushion unit 26 can be firmly coupled to the upper crankcase 5.
[0027]
Furthermore, in this embodiment, when supporting the members (the rear arm 10, the link mechanism 25, and the cushion unit 26) for suspending the rear wheel 3 on the crankcase, the support points of these members are the rear end portions of the crankcase. Since the support points are arranged as close as possible to each other as much as possible, the portion to be formed so as to increase the rigidity of the crankcase may be narrow. Therefore, the rear wheel suspension member can be supported with high rigidity while preventing the crankcase from becoming heavy. When the portion supporting the rear wheel suspension member has a high rigidity, almost the entire load can be applied to the cushion unit 26, so that the performance as designed can be obtained.
[0028]
Furthermore, since the main frame 6 does not cross the crankcase when viewed from the side, the main frame 6 does not get in the way when the cassette-type mission 18 is attached or detached. In addition, the cassette-type mission 18 can be attached and detached while the engine 4 is mounted on the vehicle body. The tank rail 6a and the footrest bracket 30 positioned on the right side of the vehicle body are formed as indicated by a broken line 6c and a two-dot chain line 30a in FIG. 2 in order to avoid interference with the cassette type mission 18.
[0029]
Incidentally, the mission abuts standing to be detachable with the engine 4 are mounted on the vehicle body, the mission may not be a cassette type. That is, a configuration in which the drive shaft and the driven shaft of the mission are supported by the joint portion between the upper crankcase and the lower crankcase may be employed. By adopting this configuration, by removing the lower crankcase from the upper crankcase, the transmission having the drive shaft and the driven shaft can be easily attached to and detached from the engine in the vehicle.
[0030]
In addition, when the upper end portion of the cushion unit 26 is supported by the upper crankcase 5, in addition to using the dedicated cushion unit bracket 27 as in this embodiment, a part of the cushion unit 26 protrudes from the upper crankcase 5. The bracket may be integrally formed, and the upper end portion of the cushion unit 26 may be pivotally supported by the bracket.
[0031]
Second Embodiment The main frame can also be configured as shown in FIGS.
FIG. 5 is a side view showing an example of an embodiment in which the main frame is formed in a box shape, and FIG. 6 is a sectional view taken along line VI-VI in FIG. In these drawings, the same or equivalent members as those described in FIGS. 1 to 4 are designated by the same reference numerals, and detailed description thereof is omitted.
[0032]
The main frame 6 shown in FIGS. 5 and 6 is integrally formed by casting aluminum alloy into a hollow box shape in which the left and right tank rails 6a, 6a serve as both side walls in the left-right direction of the vehicle body. Reference numerals 41 and 42 indicate an upper plate portion and a lower plate portion of the main frame 6. When casting into a hollow box shape, a core (not shown) is loaded into a portion that becomes a hollow portion.
The end of the main frame 6 on the vehicle body front side is welded to the head pipe 7.
[0033]
In this embodiment, the intake system is configured so that the inside of the box-shaped main frame 6 becomes an air cleaner chamber. That is, the intake pipe, the throttle valve device 13a, and the fuel injection device 13b are made to face the rear side portion of the main frame 6 in the main frame 6 from below, and the air cleaner 43 of the air duct 43 with the air cleaner element is disposed in the main frame 6 on the front side of the vehicle body. The element 43a faces from below.
[0034]
If comprised in this way, while the capacity | capacitance of an air cleaner chamber becomes large compared with the case where the said 1st Embodiment is taken, an air cleaner case becomes unnecessary and can reduce a number of parts.
As a material for forming the main frame 6, a magnesium alloy or a fiber reinforced plastic can be adopted in addition to an aluminum alloy. In forming the air cleaner chamber in the main frame 6, a frame having the left and right tank rails 6a, 6a as side walls is formed by casting, and an upper plate and a lower plate are welded to the upper and lower portions of the frame. May be. Furthermore, the main frame 6 may be welded with the upper plate and the lower plate as the configuration of the first embodiment. Further, the main frame 6 may be formed by combining aluminum alloy plate materials.
[0035]
Third Embodiment The main frame can also be formed so as to be swingable with respect to the engine as shown in FIGS.
FIG. 7 is a side view showing another embodiment in which the main frame is swingably connected to the crankcase and the swing angle is changed by an actuator, and FIG. 8 is a swingable connection of the main frame to the crankcase. FIG. 5 is a view showing another embodiment in which the swing angle is changed by a cam, wherein FIG. 5A is a side view, and FIG. 5B is a cross-sectional view taken along line BB in FIG. . In these drawings, the same or equivalent members as those described in FIGS. 1 to 4 are designated by the same reference numerals, and detailed description thereof is omitted.
[0036]
The main frame 6 shown in FIG. 7 is slidably connected to the upper crankcase 5 via a support shaft 45 that passes through a front-side portion of the vehicle body at the rear end. Further, a connecting pin 47 is fitted into a long hole 46 formed in the rear end portion of the main frame on the rear side of the vehicle body. The connecting pin 47 has a head having a diameter larger than the opening width of the long hole 46 at one end, and the other end of the connecting pin 47 facing the outer surface of the main frame 6 on the upper crankcase 5. It is stuck to.
[0037]
That is, the main frame 6 is connected to the upper crankcase 5 so as to be swingable in the vertical direction while the movement of the vehicle body in the horizontal direction is restricted by the support shaft 45 and the connecting pin 47. A hydraulic cylinder 48 supported by the upper crankcase 5 is connected to the rear end portion of the main frame 6. The hydraulic cylinder 48 has a structure in which hydraulic pressure is supplied by operating the engine 4.
[0038]
With this configuration, when the hydraulic cylinder 48 is driven to the contraction side in the state shown by the solid line in FIG. 7, the main frame 6 swings about the support shaft 45 and the end on the front side of the vehicle body moves upward. Moving. For this reason, since the head pipe (not shown) and the front fork 8 move in the same direction as the main frame 6, the caster angle of the front wheel suspension can be changed. Such a caster angle changing operation can be performed even during traveling.
[0039]
When changing the caster angle, the corner angle is set so that the caster angle is larger than that when the vehicle is traveling straight. That is, when cornering is performed with a relatively large caster angle, high turning performance is obtained, and when the caster angle is relatively small, high straight running stability is obtained. The straight running stability can be improved in this way as the trailer becomes longer due to the smaller caster angle, the distance between the front and rear axles becomes longer, and the vehicle body leans forward. This is due to three reasons that form and aerodynamics reduce air resistance.
[0040]
The main frame 6 shown in FIG. 8 has a structure in which the swing angle is changed using a cam 49 attached to a crankcase connecting portion on the rear side of the vehicle body at the rear end portion. The crankcase connecting portion on the vehicle body front side at the rear end portion of the main frame 6 has the structure shown in FIG.
The cam 49 is formed in a disc shape, and its outer peripheral surface is rotatably fitted to the main frame 6, and is connected to the cam 51 on the upper crankcase 5 side via a connecting pin 50 that is press-fitted to a position spaced from the shaft center. I am letting. Further, in order to restrict the rotation of the cam 49 during traveling, a slit 52 is formed in the main frame 6 and a lock bolt 53 is tightened.
[0041]
The cam 51 on the upper crankcase 5 side is formed in a disc shape having the same diameter as the fitting portion of the cam 49 with the main frame 6, and the connecting pin 50 is rotatably fitted to a part separated from the shaft center. In this state, the upper crankcase 5 is rotatably fitted. The distance between the axis of the cam 51 and the axis of the connecting pin 50 is the same as the distance between the axis of the cam 49 and the axis of the connecting pin 50. The upper crankcase 5 can also be provided with a binding mechanism including a slit portion and a tightening bolt for restricting the rotation of the cam 51. Thereby, the main frame 6 can be fixed more firmly.
[0042]
With this configuration, the cam 49 on the main frame 6 side and the cam 51 on the upper crankcase 5 side are rotated in a state where they are connected by the connecting pin 50, so that the main frame 6 is the upper side on the vehicle body front side at the rear end portion. The crankcase 5 swings up and down around a pivot point (not shown). Note that FIG. 8 is drawn with the main frame 6 closest to the horizontal.
Even when the configuration shown in FIG. 8 is adopted, the same effect as that obtained when the configuration shown in FIG.
[0043]
【The invention's effect】
As described above , according to the present invention, since the rear arm can be connected to the main frame via the crankcase, the rear arm bracket and the down tube are unnecessary as compared with the diamond type frame, and the main frame is shortened.
[0044]
For this reason, when adopting a configuration in which the engine is used as a part of the vehicle body frame, the number of frame components can be reduced as much as possible to reduce the weight and the cost.
[0045]
Further, according to the present invention, since the upper crankcase is a single rigid body, the main frame, the rear arm and the upper end of the cushion unit can be firmly coupled to the upper crankcase, and the engine is configured as a part of the vehicle body frame. However, a highly rigid body frame can be obtained.
[Brief description of the drawings]
FIG. 1 is a side view of a motorcycle according to the present invention.
FIG. 2 is a side view of a main part.
FIG. 3 is a cross-sectional view taken along line III-III in FIG.
FIG. 4 is a plan view showing a schematic configuration of a vehicle body frame.
FIG. 5 is a side view showing an example of an embodiment in which a main frame is formed in a box shape.
6 is a cross-sectional view taken along the line VI-VI in FIG.
FIG. 7 is a side view showing another embodiment in which the main frame is configured to be swingable.
FIG. 8 is a view showing another embodiment in which the main frame is swingably connected to the crankcase and the swing angle is changed by a cam.
[Explanation of symbols]
4 ... Engine, 5 ... Upper crankcase, 6 ... Main frame, 7 ... Head pipe, 9 ... Pivot shaft, 10 ... Rear arm, 11 ... Lower crankcase, 25 ... Link mechanism, 26 ... Cushion unit, 27 ... Cushion unit Bracket for.

Claims (1)

The crankcase can be divided into an upper crankcase and a lower crankcase in the vertical direction. The main frame extends from the head pipe to the upper part of the engine crankcase, and the rear end of the main frame is the upper part of the upper crankcase. The upper crankcase has a rear arm swingably supported, and the upper end of a cushion unit having a lower end connected to the rear arm is supported by the upper crankcase. Mounted so that it can be attached to the left and right sides of the vehicle body from one side, and overlaps the cassette-type transmission when the side fixed to the other side of the upper crankcase at the rear end of the main frame is viewed from the side of the vehicle body. A motorcycle characterized by being positioned as described above .

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