JPS6315191B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mounting structure for an engine lower guard in a motorcycle.

Generally, this type of engine lower guard protects the bottom of the engine mounted between the down tube and backstay that make up the vehicle body frame.
Its front and rear parts are attached to the lower end of the down tube and the lower end of the backstay. This type of engine lower guard may deform when it hits obstacles such as stones or curbs while driving, and if such deformation occurs, it may damage the vehicle body frame or the engine attached to it via the front and rear mounting parts. There is a problem in that the crankcase of the engine is deformed and unreasonable stress is generated. Further, the engine lower guard is often attached and detached, especially during engine maintenance and inspection, and it is desired that the engine lower guard can be easily attached and detached without requiring complicated work.

The present invention was made in view of the above-mentioned circumstances, and its main purpose is to prevent deformation of the vehicle body frame and engine even if the engine lower guard is deformed, and to prevent the engine lower guard from deforming, which requires complicated work. The purpose of the present invention is to provide an extremely simple mounting structure that can be easily attached and detached without any trouble.

Hereinafter, the present invention will be described based on the drawings. FIG. 1 shows an example of a motorcycle to which the present invention is implemented and an engine lower guard is attached. As shown in FIGS. 1 and 2, the body frame of this motorcycle includes a main pipe 12 and a down tube 13 fixed to a head pipe 11.
The main component is a backstay 14 fixed to the rear of the main pipe 12, and the engine 20
is arranged between the down tube 13 and the backstay 14, and is attached to both of them. Also,
Support member 14 provided at the lower end of the backstay 14
A has a footrest bar 15 extending in the left-right direction.
is fixed, and an engine lower guard 21 is attached between this footrest bar 15 and a bracket 13a provided at the lower end of the down tube 13.

As shown in FIGS. 3 to 5, the engine lower guard 21 includes a guard main body 21a whose side cross-sectional shape is arched with the center portion protruding downward;
A central protruding piece 21b is formed approximately at the center of the rear end of the guard body 21a and extends rearward from the bottom of the guard body 21a, and a central protrusion piece 21b is bent upward and rearward on both sides of the rear end of the guard body 21a and extends rearward. It consists of a pair of side protruding pieces 21c, which are integrally formed of synthetic resin. Further, a mounting hole 21d is formed in the front part of the bottom of the guard body 21a, and a drain hole 21f and an opening 21e for operating a drain bolt provided in the crankcase are formed in the rear part thereof. The central projecting piece 21b and the pair of side projecting pieces 21c together constitute an engaging part on the engine lower guard 21 side, and these projecting pieces 21b, 21c are
Mainly as shown in FIGS. 2 and 3, the footrest bar 15 is formed into an upper and lower bifurcated shape opening rearward when viewed from the side, and constitutes an engaging portion on the side of the backstay 14. As shown in Figure 6, it can be locked from the front side of the vehicle body.

The rear end of the engine lower guard 21 can be moved in the front-back direction and can be moved in the vertical direction by engaging the protruding pieces 21b and 21c from the front side of the vehicle body so as to sandwich the footrest bar 15 at the lower end of the back stay 14. backstay 14 so that it is restrained.
It is locked at the lower end of. In this state where the rear end is locked, the bottom front part of the guard main body 21a is located in front of the lower end of the down tube 13, and the mounting hole 21d and the bracket 13a at the lower end of the down tube 13 are connected to each other. A mounting bolt 22 is inserted into the mounting hole and is removably fastened to the lower end of the down tube 13. By the way, in a motorcycle, the front side of the lower end of the down tube 13 is a wide space due to the relationship with the front wheel and the like. Therefore, it is extremely easy to lock each protruding piece 21b, 21c onto the footrest bar 15 and operate the mounting bolt 22, so that the engine lower guard 21 can be attached to the lower end of the down tube 13 and the lower end of the back stay 14. It can be easily and securely attached to the vehicle, and will not come off due to vibrations that occur when the motorcycle is running. Also, engine 20
When you want to remove the engine lower guard 21 for maintenance inspection, etc., remove the mounting bolt 22, release the fixation between the guard body 21a and the lower end of the down tube 13, and move the engine lower guard 21 to the front side of the vehicle body. When pulled, each protruding piece 21b, 21c
comes off from the top of the footrest bar 15. As a result, the engine lower guard 21 can be easily removed without any complicated work. In addition, when reinstalling the removed engine lower guard 21, the engine lower guard 2
1 is inserted into the lower end of the down tube 13 and the back stay 14 from the front side of the vehicle body to lock each protruding piece 21b, 21c on the footrest bar 15, and then insert the front part of the guard body 21a into the lower end of the down tube 13. Tighten with the mounting bolt 22. Therefore, the engine lower guard 21 can be reattached easily and reliably without any complicated work. The engine lower guard 21 collides with obstacles such as stones and curbs while the vehicle is running, but the impact caused by the collision is absorbed by the deformation of the engine lower guard, which has an arcuate cross-section, and the impact applied to the vehicle body frame and engine 20 is reduced. Further, the deformation of the engine lower guard 21 due to such a collision is absorbed by the relative movement in the longitudinal direction between the protruding pieces 21b, 21c at the rear thereof and the footrest bar 15, and the deformation of the engine lower guard 21 due to such a collision is absorbed by the relative movement in the longitudinal direction between the protruding pieces 21b and 21c at the rear thereof and the footrest bar 15. There is no need to cause undue stress on these parts by deforming them.

In this embodiment, an example has been shown in which the engaging portion on the engine lower guard 21 side is constituted by the respective protruding pieces 21b and 21c, and the engaging portion on the back stay 14 side is constituted by the footrest bar 15. In the present invention, each protruding piece 21b, 21c
Alternatively, an engagement recess opening facing the footrest bar 15 may be formed. In addition, the present invention
Various types of automatic vehicles are equipped with an engine mounted between a down tube and a back stay that make up the vehicle body frame, and the bottom of the engine is protected by an engine lower guard installed between the lower end of the down tube and the lower end of the back stay. Of course, it can be applied to motorcycles.

As is clear from the above description, in the present invention, in the various types of motorcycles, the side cross-sectional shape of the engine lower guard is an arcuate shape with the center portion protruding downward, and the rear end of the engine lower guard is Upper and lower forked protruding pieces that open rearward are integrally formed, and the forked protruding pieces are engaged so as to sandwich a footrest bar that is fixed to the lower end of the back stay and extends in the left-right direction. The rear end of the engine lower guard is fixed to the lower end of the engine lower guard so as to be able to move relative to each other in the front-rear direction and restrained from relative movement in the vertical direction, and the front end of the engine lower guard is fixed to the lower end of the down tube. Its structural feature is that it is removably fastened to the engine lower guard, so that even if the engine lower guard is deformed due to a collision with an obstacle, it will not deform the vehicle body frame or the engine crankcase attached to it. The engine lower guard can be easily attached and detached without causing undue stress on these parts, and without any complicated work.Moreover, the footrest bar, which motorcycles are inevitably equipped with, can be easily installed and removed from the engine lower. Since it is used to lock the rear part of the guard, there is no need to provide parts for this locking on the vehicle body, and the mounting structure becomes extremely simple.

[Brief explanation of the drawing]

Fig. 1 is a side view showing an example of a motorcycle equipped with an engine lower guard according to the present invention;
The figure is an enlarged vertical side view showing the installed state of the engine lower guard, Figure 3 is an enlarged side view of the engine lower guard, Figure 4 is a rear bottom view of the engine lower guard, and Figure 5 is the same front as seen from the direction of the arrow in Figure 3. The bottom view and FIG. 6 are enlarged plan views showing the state in which the engine lower guard is attached to the rear. Explanation of symbols, 13... Down tube, 14...
...Backstay, 15...Footrest bar, 2
0...Engine, 21...Engine lower guard,
21a...Guard body, 21b, 21c...Protruding piece, 21d...Mounting hole, 22...Mounting bolt.

Claims (1)

[Claims] 1 A motorcycle in which an engine is mounted between a down tube and a back stay that constitute a body frame, and the bottom of the engine is protected by an engine lower guard installed between the lower end of the down tube and the lower end of the back stay. In the engine lower guard, the side cross-sectional shape is an arcuate shape with a central portion protruding downward, and an upper and lower bifurcated projecting piece that opens rearward is integrally formed at the rear end of the engine lower guard, The forked protruding pieces are engaged to sandwich a footrest bar which is fixed to the lower end of the backstay and extends in the left-right direction, so that the rear end of the engine lower guard can be moved relative to the front-rear direction with the lower end of the backstay. 1. A mounting structure for an engine lower guard, characterized in that the front end of the engine lower guard is removably fastened to the lower end of the down tube.