JPH0116720B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a small motorcycle suitable for, for example, shopping, and particularly to a unit swing type power unit thereof.

[Conventional technology]

In general, a unit swing type power unit integrally connects the engine and a transmission case with rear wheels, and the front end on the engine side is swingable to the lower part of the vehicle body frame via a lateral support shaft. It is mainly used in small and lightweight motorcycles such as family bikes and scooters.

[Problem to be solved by the invention]

By the way, this type of motorcycle is distributed in markets around the world, and when designing it, it is necessary to consider not only the domestic market but also foreign markets. In this case, if we try to supply all products with the same specifications to foreign countries with different conditions such as customs and people's weight, some countries will have excessive strength and will be difficult to handle due to the increased weight. Inconvenience and unnecessary consumption of resources can lead to problems.

Therefore, the present invention can be easily adapted to countries with large bodies or countries where two-seater vehicles are customary, by supporting the rear wheel axle at both ends without sacrificing its lightness or excellent appearance. To provide a power unit for a two-wheeled motor vehicle, which can be used to drive a motor vehicle, and also allows easy attachment and detachment of a rear wheel.

[Means to solve the problem]

Therefore, in the present invention, a transmission case extending rearward is fixedly installed on one left and right side of the engine, and one end of the axle of the rear wheel is supported at the rear end of the transmission case so that it can be inserted and removed in the axial direction. A power unit equipped with a silencer extending rearward in approximately symmetry with the transmission case on the other side is swingably supported below the vehicle body frame by a horizontal support shaft, and a steel plate is attached to the side surface of the engine on the silencer side. The reinforcing plate is removably fixed,
This reinforcing plate is extended rearward through the narrow space between the rear wheel tire and the muffler, and a bearing case equipped with a bearing that pivotally supports the other end of the axle can be attached and detached to the rear end of this reinforcing plate. The transmission case is characterized in that a brake for braking the rear wheels is attached to the transmission case.

[Effect]

According to this configuration, since the axle of the rear wheel is supported between the transmission case and the rear end portion of the reinforcing plate, the rigidity is improved compared to the case where the axle is cantilever-supported only by the transmission case. Additionally, by attaching the brake to the transmission case, the braking reaction force that occurs when braking the rear wheels is not applied to the reinforcing plate, which reduces the load on the reinforcing plate, making it lighter and more compact. Since the reinforcing plate itself is made of a narrow steel plate, it can be easily installed in a narrow space between the rear wheel and the muffler. Therefore, there is no need to change the muffler or shift the installation position between vehicles with and without reinforcing plates, and since the reinforcing plate is hidden from the outside by the muffler, the appearance can also be kept in good condition.

In addition, in the above configuration, since the reinforcing plate supports the other end of the axle via the removable bearing case, the bearing case can be removed from the reinforcing plate by pulling out the axle from the transmission case in the axial direction. For example, the rear wheel can be pulled out rearward from between the reinforcing plate and the transmission case while the reinforcing plate remains attached to the engine, making it easy to attach and detach the rear wheel.

〔Example〕

The present invention will be explained below based on an embodiment shown in the drawings.

In FIGS. 9 and 10, the vehicle body frame designated by reference numeral 1 is assembled by welding press-formed steel plates, and includes a main column 4 extending rearward from a front fork 3 having a front wheel 2, and a main column 4 extending rearward from a front fork 3 having a front wheel 2. It consists of a main frame 5 which is welded to a main pillar 4 at the central part of the extension.

A seat 6 is provided at the upper end of the main frame 5, and a footrest 7 is provided at the lower end.

A power unit 8 is mounted on a support shaft 9 below the vehicle body frame 1.
It is suspended so that it can swing vertically. The rear part of the power unit 8 is connected to the upper part of the main frame 5 by a shock absorber 11 equipped with a spring, and a rear wheel 12 is supported at the rear end of the power unit 8. Therefore, while driving, the rear wheel 1
When the vehicle 2 runs over an obstacle on the ground, the shock absorber 11 is compressed, and the power unit 8 rotates counterclockwise in FIG. It's getting old.

1 to 3 show details of the power unit 8, which consists of an engine 15 consisting of a cylinder, a crank chamber, a transmission gear chamber, etc.
and a transmission case 16 extending rearward from the left end of the engine 15. Transmission case 1
6 includes a transmission shaft 17 driven by an engine 15.
The axle 19 of the rear wheel 12 is rotatably supported by a gear case 18 connected to the rear end of the transmission case 16 via a bearing 20 . The left side surface of the gear case 18 is opened laterally, and the axle 19 is inserted through this opening 18a.
is inserted and removed, and the opening 18a is closed by a removable cap 21. A large reduction bevel gear 22 is fixed to one end of the axle 19 on the opening 18a side, and this large reduction bevel gear 22 connects to a small reduction bevel gear 23 provided at the rear end of the transmission shaft 17. On the other hand, they are engaged from the opening 18a side. The other end of the axle 19 protrudes outward from the gear case 18 and engages with a boss 25 of the rear wheel 12 via a spline 24 formed on this protrusion. Further, a brake 26 for braking the rear wheel 12 is provided on the axle 19.
6 is attached to the transmission case 16.

A muffler 27 is arranged on the opposite side of the transmission case 16 with the rear wheels 12 interposed therebetween. This silencer 2
7 is fixed to the right side of the engine 15 by a bolt 28, and is connected to the engine 1 through an exhaust pipe 29.
It is connected to the cylinder number 5.

By the way, a reinforcing plate 30 made of a steel plate is removably attached to the right side surface of the engine 15 on the side of the muffler 27 via bolts 31 and nuts 32. The reinforcing plate 30 is attached to the rear wheel 12 as shown in FIG.
The reinforcing plate 30 extends rearward through a narrow space between the tire 12a and the muffler 27, and details of this reinforcing plate 30 are shown in FIGS. 4 to 8. That is, the reinforcing plate 30 is formed by press-forming a steel plate into an elongated shape, and a flange 33 that is slightly bent on one side is formed on the outer peripheral edge of the reinforcing plate 30 . At the same time, a protrusion 34 having an arcuate cross section extending in the front-rear direction is formed in the center of the reinforcing plate 30, and the rigidity of the reinforcing plate 30 is increased by the protrusion 34 and the collar 33. Also,
The front end of the reinforcing plate 30 is formed into a bifurcated shape, and an insertion hole 37 through which the bolt 31 passes is formed at each end.

In addition, the reference numeral 35 is a support tube that connects the shock absorber 11, and this support tube 35 is firmly welded so as to straddle the rear upper edge of the reinforcing plate 30 and the auxiliary plate 36 spot-welded to this reinforcing plate 30. has been done.

On the other hand, a depression 38 that opens downward is formed at the lower rear end of the reinforcing plate 30. This depression 38
As shown in FIGS. 2 and 3, a bearing case 40 in which a rolling bearing 39 is fitted is incorporated therein, and a gap 46 is formed between the bearing case 40 and the recess 38. There is. The other end of the axle 19 is inserted into the bearing case 40 and is tightened and fixed with a nut 41.
It is rotatably supported by.

The bearing case 40 is equipped with a flange 42 that overlaps the outer surface of the reinforcing plate 36, and by tightening a bolt 43 inserted through the overlapping portion of the flange 42 and the reinforcing plate 30 with a nut 44, the bearing case 40 is reinforced. It is detachably attached to the plate 30. In this case, the insertion hole 45 of the bolt 43 opened in the flange 42 is formed in the shape of a long hole along the front-rear direction as shown in FIG. The position of the bearing case 40 can be adjusted back and forth by the length of the hole 45.

According to this embodiment of the present invention, the axle 19 of the rear wheel 12 is supported at both ends between the transmission case 16 and the bearing case 40 attached to the rear end of the reinforcing plate 30. The support rigidity of the axle 19 is improved compared to the case where the case 16 is supported in a cantilever manner.

Also, the brake 26 of the rear wheel 12 is connected to the transmission case 1.
Due to the attachment on the 6 side, the braking reaction force generated when the rear wheel 12 is braked does not need to be applied to the reinforcing plate 30, and the load on the reinforcing plate 30 is reduced accordingly. For this reason, even if the reinforcing plate 30 is made of steel plate, sufficient strength can be ensured, and it can be made lighter and more compact.Coupled with the fact that the reinforcing plate 30 itself is made of narrow steel plate, it is possible to It can be easily installed in a narrow space between the wheel 12 and the muffler 27, and there is no need to change the muffler 27 or shift its installation position between vehicles with and without reinforcing plates 30. .

Since the reinforcing plate 30 is located inside the muffler 27, it is hidden from the outside by the muffler 27, and a good appearance can be maintained.

In the above configuration, in order to remove the rear wheel 12, first loosen the nut 41 to release the connection between the axle 19 and the bearing case 40, and then insert the axle 19 through the opening 18a of the gear case 18 into the power unit 8.
Pull it out to the left side. Then, by loosening the bolts 43 to release the connection between the bearing case 40 and the reinforcing plate 30, and moving the bearing case 40 below the depression 38, the rear wheel 12 is pulled toward the muffler 27. The brake 26 is removed from the gear case 18, and in this state the rear wheel 12 is removed from the transmission case 16.
and the reinforcing plate 30 to the rear.

Therefore, the other end of the axle 19 is connected to the bearing case 40.
If it is removably attached to the reinforcing plate 30 via the reinforcing plate 30, the rear wheel 12 can be removed from between the reinforcing plate 30 and the transmission case 16 while the reinforcing plate 30 remains attached to the engine 15 side. This rear wheel 12
The attachment and detachment work can be done easily.

Furthermore, in this embodiment, since the bearing case 40 can be adjusted in position in the longitudinal direction over the range of the insertion hole 45, even though the axle 19 is supported at both ends, the axle 19 is It can be installed accurately at a position determined by the gear case 18 without eccentricity.

〔Effect of the invention〕

According to the present invention described in detail above, the axle of the rear wheel is supported at both ends, the rigidity is improved, the load burden on the reinforcing plate is reduced, the reinforcing plate itself can be formed compactly, and the rear wheel and a silencer. Therefore, there is no need to change the muffler or shift its installation location between vehicles with and without reinforcing plates, and since the muffler hides the reinforcing plate, the appearance can be maintained in good condition. .

Furthermore, since the reinforcing plate supports the other end of the axle via a removable bearing case, it is possible to remove the rear wheel while the reinforcing plate remains attached to the engine, allowing you to attach and detach the rear wheel. It has the advantage of being easy to work with.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, in which FIG. 1 is a partially sectional plan view of a power unit, FIG. 2 is a sectional view taken along the line - in FIG. 3, and FIG. 3 is a side view of the power unit. FIG. 4 is a plan view of the reinforcing plate, FIG. 5 is a side view of the reinforcing plate, FIG. 6 is a cross-sectional view taken along the line - in FIG. 5, and FIG. 7 is a cross-sectional view taken along the line - in FIG. FIG. 8 is a sectional view taken along the line - in FIG. 5, and FIGS. 9 and 10 are side views of the motorcycle, respectively. 1... Vehicle body frame, 8... Power unit, 9... Support shaft,
12... Rear wheel, 12a... Tire, 15... Engine, 16... Transmission case, 19... Axle, 26... Brake, 27... Silencer, 30... Reinforcement plate, 39... Rolling bearing, 40... Bearing case.

Claims (1)

[Claims] 1 A transmission case extending rearward is fixedly installed on one left and right side of the engine, and one end of the axle of the rear wheel is supported at the rear end of the transmission case so that it can be inserted and removed in the axial direction, and the transmission case is installed on the other side of the engine. A power unit equipped with a muffler that extends rearward approximately symmetrically is pivotably supported below the vehicle frame by a horizontal support shaft,
A reinforcing plate made of a steel plate is removably fixed to the side surface of the silencer side of the engine, and this reinforcing plate is extended rearward through the narrow space between the tire of the rear wheel and the muffler, and the rear end of this reinforcing plate is A power unit for a motorcycle, characterized in that a bearing case having a bearing for pivotally supporting the other end of the axle is removably attached to the transmission case, and a brake for controlling a rear wheel is attached to the transmission case.