JPH06173832A - Motor-bicycle engine - Google Patents

Abstract

PURPOSE:To mount a motor type starter on an engine exclusively for racing purpose without changing its construction extensively and also make the motor type starter easily removable. CONSTITUTION:A starter motor 22 is mounted on a crankcase cover 31 in a freely removable manner. A starter gear 25 is connected to the end portion of a generator rotor 30 through a one way clutch 27 in a freely removable manner. This starter gear 25 is axially supported by a gear cover 28, blocking up a generator storage space S, through a ball bearing 34. The motor type starter being mounted on the outside of a crankcase 14, only a starter mounting part is additionally required to mount a starter on an engine exclusively for racing purpose.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motorcycle engine, and more particularly to the structure of a motor type starter.

[0002]

2. Description of the Related Art Conventionally, as motorcycles used for racing, there are a motorcycle formed exclusively for a race and a motorcycle modified for racing on a public road. The engine mounted on the racing motorcycle (hereinafter referred to as the racing engine) is often not provided with a starting device, and the engine mounted on the motorcycle for public road driving is a kick type or motor type starting device. Was installed.

[0003]

SUMMARY OF THE INVENTION The inventor of the present invention has devised a conventional motorcycle for racing, which can be diverted from racing use to public road use. That is, public road running parts such as safety parts are detachably attached to the motorcycle for racing.

In doing so, however,
The structure of the starter was a problem. It is desirable to install a motor-type starter because it has the advantage of starting easily, but in order to attach a motor-type starter to a conventional racing engine, the structure of the crankshaft and crankcase has to be changed drastically. There must be. That is, the starter gear that transmits the power from the starter motor to the crankshaft must be newly mounted, and the crankcase must be changed to a different design that includes the starter motor and the power transmission reduction gear group. However, the cost will increase.

It is also conceivable to use an engine with a motor-type starting device for a motorcycle for public roads that can be modified for racing, but this type of engine cannot remove the entire starting device and is therefore lightweight. So, it is inferior to the engine of a motorcycle for racing. This is because a starter gear is arranged between a generator arranged on the end side of the crankshaft and a crank web, and this starter gear is connected to a starter motor via a reduction gear group for a starter in a crankcase. Because there is.

That is, even if the components of the starter are removed during the race to reduce the weight, the starter gear and the reduction gear group remain in the crankcase. Moreover, in this type of engine equipped with a motor starter, the total length of the crankshaft is increased by the amount of the starter gears mounted, and therefore a large load is applied to the bearings that rotatably support the crankshaft near the crank web. There was also the problem of being lost.

The present invention has been made in order to solve such a problem, and a motor-type starting device is mounted on a conventional racing engine without significantly changing the structures of the crankshaft and the crankcase. It is an object of the present invention to facilitate the attachment and detachment of this motor-type starting device.

[0008]

In a motorcycle engine according to the present invention, a starter motor is removably attached to a crankcase, and a starter gear is unidirectionally provided at an end portion of a generator rotor on an outer side in a vehicle width direction. This starter gear is detachably connected via a clutch,
It is rotatably supported by a bearing mounted on a lid that closes the generator accommodating space.

[0009]

Since the motor-type starting device is externally attached to the crankcase, it suffices to add a starting device mounting portion to the crankcase when the starting device is attached to the racing engine.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to FIGS. 1 is a side view of a motorcycle equipped with an engine according to the present invention, FIG. 2 is a side view of a motorcycle engine according to the present invention, FIG. 3 is a front view of the same, and FIG. 4 is a main part IV in FIG. It is a IV-line sectional view.

In these figures, 1 is a motorcycle,
This motorcycle 1 has a structure that can be appropriately changed between a public road running specification and a race specification by attaching and detaching safety parts such as a headlight, a taillight, a flasher and a rearview mirror. FIG. 1 shows a state in which the security component has been removed.

Reference numeral 2 is a frame of the motorcycle 1, 3 is a front fork which is rotatably supported by a head pipe 4 of the frame 2, and 5 is a vertical swing of a rear arm bracket 6 of the frame 2 via a pivot shaft 7. It is a rear arm that is freely supported. A steering handle 8 is attached to an upper part of the front fork 3, and a front wheel 9 is rotatably supported at a lower end thereof. A rear wheel 10 is rotatably supported on the rear arm 5.

Reference numeral 11 is a fuel tank, 12 is a seat, and 13 is an engine of the motorcycle 1. This engine 13
Is a water-cooled 2-cycle V-type 2-cylinder, and an upper cylinder 15 and a lower cylinder 16 attached to the crankcase 14 are arranged so as to have a V shape that opens forward when viewed from the side of the vehicle body. . Also, upper and lower cylinders 1
As shown in FIG. 3, the upper cylinder 15 is positioned on the left side of the vehicle body, and the lower cylinder 16 is positioned on the right side of the vehicle body with respect to the vehicle width direction.

Reference numeral 17 denotes an exhaust pipe of the upper cylinder 15,
The exhaust pipe 17 extends forward and downward from an upper cylinder 15 which is arranged upwardly upward, and is bent rearward in front of the crankcase 14, and passes directly under the engine 13 and under the pivot shaft 7 to allow the rear arm 5 to move. It is extended to the left. The large-diameter chamber portion 17a of the exhaust pipe 17
Is formed such that the portion located below the rear arm bracket 6 is thickest.

Reference numeral 18 denotes an exhaust pipe of the lower cylinder 16,
The exhaust pipe 18 extends rearward downward from the lower cylinder 16 arranged in the front lower direction so as to pass below the engine 13, and extends below the pivot shaft 7 to the right side of the rear arm 5. The large-diameter chamber portion 18a of the exhaust pipe 18 is formed such that the portion located below the front portion of the rear arm 5 is the thickest.

Reference numeral 19 denotes a carburetor for supplying fuel to the upper cylinder 15, reference numeral 20 denotes a carburetor for supplying fuel to the lower cylinder 16, both of which are attached to the crankcase 14.

Reference numeral 21 is a starting device according to the present invention. As shown in FIGS. 2 to 4, the starting device 21 includes a starter motor 22 serving as a power source, and an output gear 22a of the starter motor 22 via a reduction gear group including a first gear 23 and a second gear 24. A starter gear 25 connected thereto, a one-way clutch 27 for transmitting the rotation of the starter gear 25 to a crank shaft 26 of the engine 13, a gear cover 28 for covering the reduction gear group and the starter gear 25 on the outer side in the vehicle width direction are provided. There is.

The crankshaft 26 has its shaft end rotatably supported by the crankcase 14 via a bearing 26a, and the rotor 30 of the generator 29 is axially mounted on a portion extending from the bearing 26a to the left in the vehicle width direction. Has been done. In addition,
The rotation of the rotor 30 with respect to the crankshaft 26 is restricted by a key. The coil assembly 29a of the generator 29 is supported and fixed to the crankcase. The crankshaft 26 is formed as a race-dedicated engine so that the extending portion is as short as possible in order to reduce the weight.

The starter motor 22 is mounted with its axis parallel to the vehicle width direction, and as shown in FIG. 4, the output gear side end is fitted to the crankcase cover 31 that closes the left side opening of the crankcase 14. They are aligned and positioned and attached via a bracket (not shown).
Further, the structure of the portion that fixes the starter motor 22 to the crankcase cover 31 is configured such that the starter motor 22 can be attached and detached by loosening the screw or the like.

The mounting position of the starter motor 22 is set below the crankcase 14 and substantially directly below the crankshaft 29. In other words, as shown in FIGS. 2 and 3, the starter motor 22 is located between the crankcase 14 and a relatively thin portion of the exhaust pipe 17 on the upstream side of the chamber portion 17a and upstream of the exhaust pipe 18. It is located just at the left side of the vehicle at the side edge.

The first gear 23 is a two-stage gear having a first gear 23a and a second gear 23b having different diameters,
It is rotatably supported by a support shaft 32 which is parallel to the vehicle width direction. The large-diameter first gear 23 a meshes with the output gear 22 a of the starter motor 22, and the small-diameter second gear 23 a
b meshes with a second gear 24 described later. Second gear 2
4 is also a two-stage gear having a third gear 24a and a fourth gear 24b having different diameters, and a spindle 3 parallel to the spindle 32.
3 is rotatably supported. The large-diameter third gear 24a meshes with the second gear 23b, and the small-diameter fourth gear 24b meshes with a gear 25a of a starter gear 25 described later. One end of each of the support shafts 32 and 33 is fitted and supported by the crankcase cover 31, and the other end is fitted and supported by the gear cover 28.

The starter gear 25, which is gear-coupled to the fourth gear 24b, has a cylindrical inner ring 27a of a one-way clutch 27 fixed to the axial center thereof, and a ball bearing 34 fitted in the inner peripheral portion of the inner ring 27a. The gear cover 28 is rotatably supported via the gear cover 28. The connection structure between the ball bearing 34 and the gear cover 28 is a structure in which the inner ring of the ball bearing 34 is fitted to a boss portion 28a projecting inward from the plate-shaped portion of the gear cover 28.

The one-way clutch 27 includes an inner ring 27a having a starter gear 25, an outer ring 27b arranged on the outer peripheral side of the inner ring 27a, and a roller 27c interposed between the inner ring 27a and the outer ring 27b. Further, it is a well-known roller type and has a structure in which the driving force is transmitted only from the inner ring 27a to the outer ring 27b. The outer ring 27b of the one-way clutch 27 is connected to the rotor 30 of the generator 29.
Is screwed to the outer end of the vehicle in the vehicle width direction.

The gear cover 28 includes the support shafts 32, 3
3 and the ball bearing 34 are integrally supported (supporting shaft fitting hole and boss portion 28).
a) is provided in series and is screwed to the crankcase cover 31. By screwing the gear cover 28 to the crankcase cover 31, the space S for accommodating the reduction gear group, the starter gear 25, the one-way clutch 27 and the generator 29 is closed by the gear cover 28.

In the starting device 21 thus constructed,
When the starter motor 22 is energized and the output gear 22a rotates when the engine is started, the rotation is transmitted to the starter gear 25 via the first gear 23 and the second gear 24. Then, the inner ring 27a of the one-way clutch 27 rotates together with the starter gear 25, and along with this, the outer ring 27b.
Rotate in the same direction, and the rotor 30 and the crankshaft 26 of the generator 29 rotate. In this way, the crankshaft 26
The engine 13 is started by driving the engine to rotate.

The starting device 21 is also used in the motorcycle 1.
When the race specification is not set, it is attached to the engine 13 as shown in FIGS. 1 to 4, and when the race specification is set, it is removed from the engine 13. Note that the work of attaching and detaching the starting device 21 to and from the engine 13 is performed by the engine 13
Is carried out with the vehicle mounted on the vehicle body. To remove the starting device 21 from the engine 13, first, the gear cover 28 is removed from the crankcase cover 31, and the first gear 23, the second gear 24, and the starter gear 25 are removed. At this time, the starter gear 25 is the inner ring 27 of the one-way clutch 27.
It comes off from the outer ring 27b side together with a.

Then, the outer ring 27b of the one-way clutch 27.
Is removed from the generator 29 together with the roller 27c. After removing the reduction gear group, the starter gear 25, the one-way clutch 27, and the like from the engine 13 in this manner, the crankcase cover 31 is removed from the crankcase 14, and the starter motor 22 is removed from the crankcase cover 31. The crankcase cover 31 is attached to the crankcase 14 again after the starter motor 22 is removed. In this way, the entire starting device 21 is removed from the engine 13.

Next, the opening of the crankcase cover 31 is closed. At this time, the previously removed gear cover 28 may be attached to the crankcase cover 31, but in order to reduce the weight, a substantially flat plate-shaped gear cover (without the spindle fitting hole, the boss portion 28a, etc.) is formed. It is desirable to attach (not shown).

To install the starting device 21 in order to change the race specification to the public road running specification, a procedure reverse to the above-mentioned procedure is performed. That is, first, the flat plate-shaped cover and the crankcase cover 31 are removed from the crankcase 14, and the starter motor 22 is attached to the crankcase cover 31. Then, after the crankcase cover 31 is attached to the crankcase 14 again, the one-way clutch 27 and the starter gear 25 are attached to the generator 29, and the first gear 23 and the second gear 24 are attached to the crankcase cover 31. Finally the gear cover 28
Install.

Therefore, according to the invention, the starting device 21
Will be externally attached to the crankcase 14,
When installing a motor-type starter on a conventional racing engine, all that is required is to add a starter attachment to the crankcase.

Although the starter motor 22 is detachably attached to the crankcase cover 31 in this embodiment, the starter motor 22 may be fixed to the crankcase 14 by, for example, a band type fastener.
Further, in the present embodiment, the example in which the starter motor 22 is removed when the race specification is adopted is shown, but the starter motor 22 may not necessarily be removed.

Further, in the present embodiment, the ball bearing 34 is used as the bearing for supporting the starter gear 25, but a needle roller bearing may be used as shown in FIG. FIG. 5 is a cross-sectional view showing another embodiment of the starting device, in which the same or equivalent members as those described in FIGS. 1 to 4 are designated by the same reference numerals and detailed description thereof will be omitted.

In FIG. 5, reference numeral 41 denotes a needle roller bearing that rotatably supports the starter gear 25. The needle roller bearing 41 is interposed between the boss portion 28 a on the gear cover 28 side and the inner ring 27 a of the one-way clutch 27. The boss portion 28a is formed on the auxiliary cover 41 which is formed separately from the gear cover 28 and is screwed to the gear cover 28 from the outside of the case.

As described above, the boss portion 28a is attached to the gear cover 28.
The member (auxiliary cover 41) that is separate from that is that the needle roller bearing 41 is attached to the inner ring 27a while the starter gear 25 and the one-way clutch 27 are assembled to the generator 29.
When the reduction gear group is attached to the crankcase cover 31 after that, the needle roller bearing 41 is attached to the inner ring 2
This is because it is easy to fall off from 7a. That is, the reduction gear group is attached and the gear cover 28 is attached to the crankcase cover 31.
After mounting the needle roller bearing 41 on the inner ring 27a and immediately mounting the auxiliary cover 42 on the gear cover 28, the needle roller bearing 41 can be fitted into the boss portion 28a without falling off.

Even if the needle roller bearing 41 is used as shown in FIG. 5, the same effect as in the above embodiment can be obtained.

[0036]

As described above, in the motorcycle engine according to the present invention, the starter motor is detachably attached to the crankcase, and the starter gear is provided at the outer end of the generator rotor in the vehicle width direction. The starter gear was detachably connected via a directional clutch, and this starter gear was pivotally supported by a bearing mounted on the lid that closed the generator housing space.Therefore, the motor-type starter was externally attached to the crankcase and started to the racing engine. To install the device, all you have to do is add the starter mounting part to the crankcase.

Therefore, it is possible to mount the motor type starter on the engine dedicated to the race without largely changing the structures of the crankshaft and the crankcase.
This motor type starting device can be easily attached and detached.

Therefore, the weight can be reduced by removing all of the motor type starting device at the time of a race, and the starting can be easily performed by the motor type starting device at the time of traveling on a public road.

[Brief description of drawings]

FIG. 1 is a side view of a motorcycle equipped with an engine according to the present invention.

FIG. 2 is a side view of the motorcycle engine according to the present invention.

FIG. 3 is a front view of the motorcycle engine according to the present invention.

FIG. 4 is a sectional view taken along the line IV-IV of a main part in FIG.

FIG. 5 is a sectional view showing another embodiment of the starting device.

[Description of Reference Signs] 13 engine 14 crankcase 21 starter 22 starter motor 23 first gear 24 second gear 25 starter gear 26 crankshaft 27 one-way clutch 28 gear cover 28a boss 29 generator 30 rotor 31 crankcase cover 34 ball bearing 41 Needle roller bearing 42 Auxiliary cover

Claims (1)

[Claims] 1. In a motorcycle engine in which a generator is provided at a shaft end portion of a crankshaft, a starter motor is detachably attached to a crankcase, and
A starter gear rotated by the starter motor is detachably connected to an end of the generator rotor on the outer side in the vehicle width direction through a one-way clutch, and the starter gear is attached to a lid that closes the generator accommodating space. A motorcycle engine characterized by being axially supported by a fixed bearing.