JPS6363432B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a motorcycle in which a body frame is divided into a front part and a rear part.

Conventionally, the vehicle body frame is divided into a front frame on which the engine is mounted and a rear frame on which a passenger seat is placed, and the rear end of the front frame and the front end of the rear frame are removably connected. A motorcycle is already known in which the upper end of a shock absorber fixed and connected to a rear wheel swing arm is supported at the upper rear end of a front frame (for example, Japanese Patent Laid-Open No. 15086/1986). . However, with the above conventional configuration, although it is possible to improve assembly workability by making the frame smaller and smaller, and to reduce the weight of the rear frame by supporting the shock absorber on the front frame, the front frame does not have a space for attaching the rear frame. Since the bracket and the bracket for mounting the shock absorber are provided separately, the structure becomes complicated, the number of manufacturing steps increases, and costs inevitably increase.

In view of the above problems, the present invention simplifies the configuration by supporting the upper front end of the rear frame and the upper end of the shock absorber with a single left-right support shaft provided on the front frame, thereby simplifying the manufacturing process. The purpose of this invention is to improve productivity by reducing the number of parts, and the present invention will be described below based on the drawings.

Figure 1 is a schematic diagram of the left side of a motorcycle;
The vehicle body frame 1 is made up of a combined body of a front frame 2 and a rear frame 3. The front frame 2 has a head tube 4 at its front end that rotatably supports a steering member (not shown), and has two left and right substantially parallel main frames 5 extending rearward from the tube 4. Further, the down tube 6 whose upper end is welded to the head tube 4 is a symmetrical tube with two left and right sides arranged in a backward downward position, and a sub-frame 7 for reinforcement is provided between the frame 5 and the tube 6. A gusset 8 in the form of a flat plate is welded to each side of the head tube 4, main frame 5, and down tube 6.
A rear tube 9 whose upper end is welded to the rear part of the main frame 5 extends substantially downward, and the lower end of the tube 9 and the lower end of the down tube 6 are curved to face each other and are connected by a lower frame 10. There is. The main frame 5, down tube 6, rear tube 9, and lower frame 10 are as follows:
Two of each are arranged at substantially symmetrical intervals across the vehicle center line when viewed from above, and are connected in a substantially annular shape when viewed from the side. Each pair of members is connected together by a pipe (not shown).

The down tube 6, the rear tube 9, and the lower frame 10 are connected as shown in FIG. 2, which is an enlarged view of the connected portion. In FIG. 2, a concentric semi-cylindrical half joint 11 is welded to the outer circumferential surface of the tip of the tube 6, with half of the joint 11 protruding from the tip of the tube 6. A half-split joint 12 having the same shape as the joint 11 is welded to the outer peripheral surface of the tip end of the frame 10 at a position that matches the joint 11 to form a ring as shown in FIG. Half of the joint 12 protrudes from the frame 10 and fits into the tube 6. Therefore, when the longitudinal flanges 13 formed at the circumferential ends of the respective joints 11 and 12 are opposed to each other with a slight gap between them and are fastened with four tangential bolts 14, the tube 6 and Both ends of the frame 10 are concentrically connected. Rear tube 9 and lower frame 1 in Figure 1
0 is also removably connected by the same structure.

In FIG. 1, a cross pipe 15 is welded in a direction perpendicular to the tube 9 (horizontal direction) between a rear tube 9 on the left side of the vehicle body and a rear tube of the same shape on the right side of the vehicle body (not shown). The front end of a bell crank 18 is rotatably supported by the bracket 16 via a support shaft 17 parallel to the pipe 15. The lower end of the shock absorber 20 is rotatably supported at the rear end of the bell crank 18 via a support shaft 19 parallel to the pipe 15, and the upper end of the shock absorber 20 is attached to the rear end of the main frame 5. By being supported (detailed later),
The shock absorber 20 is held in a forward tilted position. On the other hand, the front end of the swing arm 24 that rotatably supports the rear wheel 22 via the rear axle 23 is rotatably supported by a pivot shaft 25 parallel to the pipe 15, and the shaft 25 is welded to the rear tube 9. It is fixed to a bracket 27. The swing arms 24 extend rearward symmetrically on both sides with the rear wheel 22 in between, and a cross pipe 28 is fixed between the intermediate portions of both arms 24 to integrally connect both arms. The upper ends of two brackets 29 (only the left side is shown) arranged on the left and right sides are welded to the lower surface of the cross pipe 28, and both brackets 29 have two tension rods 30 (only the left side shown) that sandwich the bell crank 18 from both sides. (as shown) are rotatably supported via support shafts 31 (only the left side is shown) in the left and right directions, respectively. The two tension rods 30 extend symmetrically forward and downward, and the front ends of both rods 30
It is rotatably supported at the middle part of the bell crank 18 via a book support shaft 32.

The back frame pipes 33 of the rear frame 3, which are arranged behind the front frame 2 and above the rear wheels 22, extend approximately horizontally in the front-rear direction and are provided in two symmetrical shapes (only the left side is shown). The rear ends are integrally formed via a grip pipe 34 curved in a U shape, and both pipes 33 are firmly integrated by an appropriate number of cross pipes installed in the left-right direction between the two pipes 33. Here, the front end of the pipe 33 is supported by the rear end of the main frame 5 as shown in FIG. In FIG. 4, boss portions 35 and 36 are formed at the rear ends of the two main frames 5 extending in parallel in the front-rear direction.
5 and 36 are provided with holes 37 and 38 in the left and right direction. One hole 37 has a step 39, and the tip of the spindle main body 40 inserted from the other hole 38 side fits into the hole 37 until it abuts the step 39, and is integrally attached to the spindle main body 40. The formed head portion 41 is in contact with the outer end surface of the boss portion 36. Support shaft body 4
A concentric female thread 42 is formed at the tip end on the boss part 35 side of 0, and a male thread of a support shaft part 43 inserted into the hole 37 from the outside of the boss part 35 is screwed into the female thread 42. A support shaft 44 consisting of a support shaft body 40 and a support shaft portion 43 is fixed to both boss portions 35 and 36. On the other hand, the front end 33a of the back frame pipe 33 is crushed and formed into a vertical flat plate shape, and bolts 52, 53 are inserted from the outside into left-right holes 50, 51 formed in the front end 33a. The tips of the bolts 53 and 52 are screwed into concentric internal threads 47 and 46 formed outward in the head portion 41 of the spindle body 40 and the head portion 45 of the spindle portion 43, respectively. pipe 3
3 is fixed to a support shaft 44. The shock absorber 20 is composed of a shock absorber main body 54 and a coil spring 55, and a hole 57 in the left and right direction of a boss portion 56 formed at the upper end of the shock absorber 20 is inserted into the center of the support shaft 44 through a sleeve 58. The boss portion 5 is rotatably fitted and supported on the boss portion 5.
Collars 48 and 49 for positioning in the left and right direction are fitted on both the left and right sides of 6.

On the other hand, as shown in FIG. 1, on the intermediate lower surface of each back frame pipe 33 on both the left and right sides, there are back stays 21 disposed on both sides of the vehicle body in a forward downward position.
(Only the left side is shown) The rear upper end is welded,
The front end of the backstay 21 is supported by a bracket 27 as shown in FIG. That is, in FIG. 5, the cross section welded to the rear tube 9 is approximately U.
The shaped bracket 27 has holes 59 concentric in the left and right direction,
60 is formed, and a cylindrical bush 61 is fitted and welded into the holes 59 and 60. A flange portion 62 is integrally formed at one end of the bush 61, and a female thread 6 is provided concentrically with the bush 61 toward the outside.
3 is provided. The front end 21a of the backstay 21 is crushed to form a flat plate in the vertical direction, and a bolt 65 inserted into a hole 64 in the left-right direction of the front end 21a is screwed into a female screw 63, so that the backstay 21 is fixed to the bushing 61. Of course, the backstay on the right side (not shown) is also symmetrical and has a similar configuration.

In addition, in FIG. 1, 66 is the main frame 5.
67 is an engine mounted in a space surrounded by the front frame 2;
8 is a sheet placed on the back frame pipe 33.

Next, the operation of the load absorption mechanism of the rear wheel 22 (FIG. 1) will be explained. The shock absorber 20 always biases the bell crank 18 in the direction of arrow _X1 , and as a result, the swing arm 24 is constantly biased in the direction of arrow _X2 via the tension rod 30. If the rear wheel 22 receives an upward force and the swing arm 24 rotates in the reverse _X2 direction, the bell crank 18 is rotated in the reverse _X1 direction via the tension rod 30, and the shock absorber 20 rotates in the reverse X1 direction. The load is absorbed by being compressed.

Further, the work for attaching and detaching the engine 67 is performed, for example, as follows. In order to mount the engine 67 on the frame 1, the front frame 2 with the lower frame 10 removed is
is placed over the engine 67 from above, and the engine is fixed to brackets (not shown) provided on the down tube 6 and rear tube 9. After that, the lower frame 10 is placed between the lower ends of the tubes 6 and 9, and the half-split joint 1 is inserted as shown in FIGS. 2 and 3.
2 and 13 and tighten with bolt 14. When removing the engine 67, the procedure is reversed.
Note that the lower frame 10 is provided only on one side (for example, the left side) of the two tubes 6 and 9 provided on both the left and right sides, and the lower ends of the tubes 6 and 9 are simply connected together on the other side. In the case of this type, it is sufficient to cover the engine 67 with the frame 2 in an oblique direction.

As explained above, according to the present invention, the frame 1 is divided into the front frame 2 on which the engine 67 is mounted and the rear frame 3 on which the seat 63 is arranged, and the rear end of the front frame 2 and the rear part are separated. The front end of the frame 3 is removably connected and fixed, and a rear wheel swing arm 24 is attached to the upper rear end of the front frame 2.
In a frame-split type motorcycle that supports the upper end of a shock absorber 20 connected to Since the upper front end of the rear frame 3 and the upper end of the shock absorber 20 are supported, the support structure for the rear frame 3 and the shock absorber 20 to the front frame 2 is extremely simple, and assembly is simplified, reducing the manufacturing process. This has the advantage that productivity can be improved and costs can be reduced.

Further, according to the above embodiment, the bolt 5 is attached to the support shaft 44.
2 and 53 to fasten the back frame pipe 33, the shock absorber 20 is assembled to the front frame 2 in advance using the support shaft 44, and then the rear frame 3 is attached to the front frame 2. Since it can be fixed to the shock absorber 2, it not only improves assembly work efficiency, but also allows the rear frame 3 to be removed during maintenance work.
0 can be exposed, which has the advantage of improving workability.

In carrying out the present invention, one bolt (another embodiment of the support shaft) is used instead of the support shaft 44 and the bolts 52, 53 to connect the pipe 33, the boss portions 35, 36,
It is also possible to have a configuration in which the hole 56 is penetrated. In this case, there is an advantage that the configuration is further simplified. On the other hand, since a large load is not applied to the rear frame 3, it is possible to reduce the weight by making it made of aluminum or magnesium alloy. Further, the present invention can also be adopted in a motorcycle having one main frame 5, an example of which is shown in FIG.

[Brief explanation of drawings]

Fig. 1 is a schematic view of the left side of the motorcycle according to the present invention, Fig. 2 is an exploded perspective view of the connecting portion between the down tube and the lower frame, Fig. 2a is a view taken from arrow a in Fig. 2, and Fig. 3 is - Sectional view of Fig. 2, No. 4
Figure 5 is a cross-sectional view of Figure 1, respectively.
- A sectional view, FIG. 6 is a view corresponding to FIG. 4 of another embodiment. 1...Frame, 2...Front frame, 3...
Rear frame, 20...Shock absorber, 2
4... Swing arm, 44... Support shaft, 67...
Engine, 68...seat.

Claims (1)

[Claims] 1. The frame is divided into a front frame on which the engine is mounted and a rear frame on which the seat is arranged, and the rear end of the front frame and the front end of the rear frame are removably connected and fixed. In a frame split type motorcycle in which the upper end of the shock absorber connected to the rear wheel swing arm is supported at the upper rear end of the frame, one support shaft in the left and right direction is provided at the upper rear end of the front frame, A split-frame motorcycle, characterized in that the upper front end of the rear frame and the upper end of the shock absorber are supported by the support shaft.