JPS6245053Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to a cooling system for an air-cooled engine in a small vehicle.

(Prior Art) Since the engine of a two-wheeled vehicle is exposed, even if an air-cooled engine is installed, the entire surrounding area becomes a cooling air, and effective cooling can be achieved. However, when this type of engine is mounted on a tricycle or the like and a cover is provided around it, it is necessary to provide forced air cooling means such as a cooling fan, especially when the drive device including the engine is installed adjacent to the wheels. In order to take in cooling air, a partition plate is installed between the wheels and the fan to form a cooling device.

As such an engine cooling device, the one described in Japanese Utility Model Publication No. 40-23533 is known. This cooling system consists of a spiral-shaped front plate, a friction plate with the same shape and a through hole in the center, and a side plate wrapped around and fixed to form a spiral-shaped case in the center.This case is attached to the engine. Attached to the cooling air intake hole to prevent muddy water, etc. from entering the cooling air intake hole.

(Problem that the invention aims to solve) However, in the case of the conventional engine cooling system as described above, the case is formed by wrapping the front plate and the side plate and fixing them, so the case is large. This poses a problem in that the engine is bulky and heavy, making it practically impossible to install it in a vehicle such as a passenger vehicle where engine size and weight are restricted. Particularly in the case of passenger vehicles, the engine is covered with a cover or the like for soundproofing, but if such a case is provided as described above, the cover becomes large and the whole engine becomes huge.

This invention was made in view of the above-mentioned problems, and aims to provide an engine cooling device that can be made smaller and lighter.

(Means for Solving the Problems) This invention places an engine 31 between two driving wheels 20, 20, covers these driving wheels 20, 20 and the engine 31 with a fender 21, and surrounds the engine 31. A cooling air duct 55 is provided in the cooling air duct 55, and the crankshaft 35 is installed in the cooling air duct 55.
In an air-cooled engine cooling device in which outside air is forcibly guided through an outside air intake duct 56 by a cooling fan 53 provided in the outside air intake duct 56, the cooling fan 53 is provided in the outside air intake duct 56. A crank case 32 is provided between the drive wheel 20 on the side and the engine 31, and is provided on the side where the cooling fan 53 is provided and is located on the outside of the crankshaft 35 in the longitudinal direction.
An outer wall 32e is provided in the outer wall 32e, and an opening 32g is provided inside the outer wall 32e and is opened substantially upward in the radial direction of the cooling fan 53, is connected to the outside air intake duct 56, and guides outside air into the cooling air duct 55. A partition wall 21a is provided between a portion of the fender 21 that covers the drive wheels 20 and a portion that covers the engine 31.
hangs down from the partition wall 21a and the outer wall 5 of the outside air intake duct 56.
4b, and the drive wheel 20 and the engine storage section are partitioned by the partition wall 21a, the outer wall 54b of the outside air intake duct 56, and the outer wall 32e of the crankcase 32.

(Function) According to the air-cooled engine cooling device according to this invention, cooling air is guided from the outside air intake duct to the cooling air duct by the cooling fan, and the engine is forcibly cooled. The engine housing section is defined by the partition wall hanging down from the fender and the outer wall of the outside air intake duct, and the engine is covered by the partition wall and the outer wall to prevent muddy water and the like from adhering to the engine. Further, since the duct is defined on the side of the engine using a partition wall that is a part of the fender, it can be made smaller and lighter, and the overall size can be made smaller. Furthermore, since the partition wall and the outer wall connected to the partition wall cover almost the entire periphery of the engine, the engine is entirely covered by the fender together with the partition wall and the outer wall, thereby preventing engine noise from dissipating to the outside.

(Example) Hereinafter, an example of this invention will be described based on the drawings.

Figures 1 to 5 show a cooling system for an air-cooled engine according to an embodiment of this invention, with Figure 1 being a side view of the tricycle, Figure 2 being a plan view of the tricycle, and Figure 3 showing the main parts. FIG. 4 is a sectional view taken along arrows 4-4 in FIG. 3, and FIG. 5 is a sectional view taken along arrows 5-5 in FIG. 3. In this embodiment, the present invention is applied to a three-wheeled vehicle, but it goes without saying that the present invention can also be applied to a four-wheeled vehicle.

The tricycle 1 consists of a front body 2 and a rear body 3. The front body 2 has a low-floor structure similar to that of a scooter, and has a front fender part 4 at the very front, which slopes diagonally rearward and downward from the rear of the fender part 4. It has a front part 5 and a floor part 6 extending flatly to the rear. Floor part 6
A box-like raised wall portion 7 is provided at the rear of the vehicle so as to extend substantially completely across the width direction, and functions as a foot guard to prevent the occupant's feet from moving rearward.

A support post 9 for a front fork 8 is installed on the front part 5 of the front body 2, and the lower part of the front fork 8 stores the single front steering wheel 10, and the upper end stores a bar handle 11, a headlight, and meters. , a supporting case 12 is provided. A seat post 13 is provided on the central portion of the raised wall portion 7, and a seat 14 for a passenger is placed on the seat post 13.

A joint 15 is provided on the rear lower surface of the front vehicle body 2,
A rear sub-frame 17 of the rear vehicle body 3 is connected to the rear end of the rotational swing support shaft 16, and this frame 17
A rear fork 18 is pivotally attached to the rear fork 18 so as to be swingable about a pin 19. And rear fork 18
A drive device 30 is mounted on the top, and the drive device 30 is disposed between the rear two drive wheels 20, 20, and is housed within the outline of the drive wheels 20, and is arranged between the left and right wheels 2.
0, 20 and the drive device 30 are covered with a rear fender member 21. The front vehicle body 2 is rotatably swingable in the left-right direction with respect to the rear vehicle body 3. As is clear from FIG. 2, the tread between the rear wheels 20, 20 is approximately equal to the width of the floor portion 6 of the front vehicle body 2.

As shown in FIGS. 4 and 5, the drive device 30 is entirely housed in a case 32 that serves as both a crankcase and a transmission case. In addition, in FIG. 5, the engine part protrudes above the wheel 20 due to the cross-sectional view of the arrow, but in reality, the engine part protrudes above the wheel 20.
The entire drive device 30 is housed within the outline of the vehicle. The case 32 has halves 32a that can be divided into upper and lower halves,
The cylinder 33 and cylinder head 34 that constitute the engine 31 are assembled to the upper half body 32a, and the axle 4 is assembled to the lower half body 32b.
3 is supported. The lower half 32b is divided into two parts.
It is constructed by joining two divided bodies, and FIG. 5 shows the dividing plane. Inside the case 32, a crankshaft 35 is supported horizontally at the junction of the halves 32a and 32b, and the left and right journal parts of the crankshaft 35 are supported by bearings 36, and are connected to a piston 38 via a connecting rod 37. connected. A clutch inner 39 and a drive gear 40 are fixed to one end of the crankshaft 35.
A centrifugal clutch 4 consisting of a clutch outer 41 connected to a crankshaft end fitting member that also serves as a
2 is provided, and the inner 39 and outer 41 are connected to each other at a predetermined rotation speed of the crankshaft 35, and the output is output to the drive gear 40.

An axle 43 is horizontally suspended in the case 32 so as to be parallel to and adjacent to the crankshaft 35.
3 consists of a right drive wheel 44, an intermediate shaft 45 spline-fitted to this, and a left drive shaft 46 loosely engaged with the intermediate shaft 45, and each of the shafts 44 to 46 are arranged on the same axis. Flange portions 47 and 48 are provided at opposite ends of the intermediate shaft 45 and the drive shaft 46, and a friction material such as a ring-shaped clutch facing 49 is interposed between the flanges, and the facing 49 is not fixed.
It is locked to one flange portion 47. The center shaft 45 is compressed to the left in the drawing by springs 50 and 50 compressed between it and the right drive shaft 44, and the flange portion 47 is pressed against the flange portion 48 via the facing 49, causing friction between the shafts 45 and 46. Connect with clutch. The above axle 43 is connected to the driven gear 51 provided on the drive shaft 44 and the drive gear 4 described above.
0, and the left and right drive shafts 44, 46
The left and right wheels 20, 20 are installed at the extending end of the case 32.
The wheels 20, 20 are driven by an axle 43, and friction clutches 47, 48, 49 provide differential movement between the wheels 20, 20 due to the difference in internal and external rotation. Although not shown, the flange portions 47, 4
A caliper was provided on a part of the outer side of the 8, so that it also served as the brake disc of the disc brake device.

At the other end extending portion 35a of the crankshaft 35,
A flywheel 51, which also serves as a magnet mounting base for the ACG (generator), is attached, and the flywheel 51 has a drum shape, and a plurality of fins 52 are attached to the outer surface of the outer wall 51a of the flywheel 51, which improves air blowing efficiency, for cooling. A fan 53 is configured. A cooling fan 53 provided at the end of the crankshaft is provided within the case 32. The case 32 has an opening 32c in the part where the fan 53 is located.
and an outer wall 32e spaced further outside of the inner partition wall 32d provided with the opening 32,
An outside air intake duct 32f is provided between the outer wall 32e and the inner wall 32d, and the bottom of the duct 32f faces the aforementioned friction clutches 47, 48, 49. Duct 3
2f is separated from the left wheel 20 by an outer wall 32e, and an opening 32g is formed at the upper end of the duct 32f, as shown in FIG. . The above-mentioned inner wall 32 is the part facing the upper part of the cooling fan 53.
Between the upper part 32h of the opening 32c of d and the wall 32i that partitions the flywheel 51 and the cylinder 33, there is a connection path 32j in which a part of the fan 53 is loosely connected.
This connection path 32j opens to the side of the engine 31 assembled on the case 32.

Cover 54 around the engine 31 times, cover 5
4 is fixedly supported on the case 32. A part of the cover 54 is bulged out laterally 54a, and this is connected to the wall 32h of the connection path 32j described above, to form a bulge space 55 around the corresponding part of the engine 31 that communicates with the connection path 32j, This space 55 constitutes a cooling air duct around the cylinder 33 and cylinder head 34 of the engine 31. A portion of the cover 54 adjacent to the cooling air duct 55 is partitioned by the wall of the bulging portion 54a to form an outside air intake duct 56. Note that this duct 56, the above-mentioned intake duct 32f, and the cooling air duct 55 correspond to the engine housing section. duct 56
is separated from the cooling air duct 55 by a wall 54a and from the outside by a wall 54b, the upper part is opened to the atmosphere from the front opening of the rear fender 21 through the space inside the rear fender 21, and the lower part is the duct 56 as described above. It is connected to the intake port 32g. and wall 54
A partition wall 21a hanging down from the rear surface of the rear fender 21 contacts b, and the partition wall 21a and the wall 54
The wheel 20 and the engine storage section are partitioned by b.
An opening 54c communicating with the outside air is formed at the upper end of the wall 54b inside the partition wall 21a.

Next, to explain the operation and effect in detail, the cooling fan 53 is driven by the drive of the crankshaft 35.
As a result, outside air is introduced from the front opening of the rear fender 21 through the opening 54c and ducts 56, 32f, and the outside air is introduced by the fan 53 from the connection path 32j into the duct 55 inside the cover 54 around the engine 31, It flows around the cylinder 33 and cylinder head 34 to cool them, and the cover 54 and case 3
2 (see Figure 4). In such cooling, the intake ducts 56, 32
f is separated from the wheels 20, so no muddy water etc. can enter, and since the drive device 30 is provided within the outer contour of the wheel 20 and the cooling air intake is also provided within the outer contour, muddy water etc. It is not fed by getting it caught in the intake part. That is, the muddy water etc. that scatters from the driving wheel 20 side on the left side in FIG. Case 3
Case 32 is obstructed by the wall on the right side in the figure
Muddy water etc. will not enter inside. Therefore, it is possible to prevent mud from adhering to or accumulating on the cylinder and cylinder head, thereby reducing the cooling effect, and to ensure effective cooling over a long period of time.In particular, it is possible to perform cooling in the rain while preventing the above-mentioned problems. . The ducts 56, 32f, 55, etc. are arranged on the side of the engine 31, where there is a relatively large margin, and are installed on the walls of the existing case 32, cover 54, etc., and on the flat wall 54.
b etc. Therefore, this cooling device can reduce the number of parts, be smaller in size, and be lighter in weight, and can be easily installed in a passenger tricycle as illustrated without increasing the overall size.

On the other hand, the drive device 30 is covered on the sides by the outer wall 32e of the case 32, the internal partition wall 32d, the bulge 54a of the cover 54, etc., and is covered above by the rear fender 21 together with the cover. The defined ducts 56, 32f, 55 are bent at a substantially right angle at the connection portion. Therefore, the noise generated by the engine 31 and the like is blocked by the case 32, the cover 54, the rear fender 21, and the like, and its radiation to the outside is suppressed.

Additionally, an opening 32 connected to the outside air intake duct 56
g is formed on the inner side of the outer wall 32e of the crankcase 32, so that it faces almost upward in the radial direction of the cooling fan 53, so that the joining part of the outside air intake duct 56 and the crankcase 32 is in the upper position, so that when driving in the rain, etc. Outside air intake duct 56 and crankcase 3
It is possible to prevent muddy water, etc. from entering into the duct from the joint part of 2.

In addition, the outside air intake duct 56 and the crankcase 3
2 is located at the upper level, and the length of the outside air intake duct 56 in the vertical direction can be shortened, thereby ensuring the rigidity of the outside air intake duct 56 and simplifying the structure of the outside air intake duct 56. .

In addition, in the embodiment described above, the crankcase 3
Since the cooling fan 53 is provided at the 5th end, there is no need for parts or structures such as a transmission mechanism for the cooling fan 53 or its support, making it possible to simplify the structure and reduce the number of parts. The outer shape of the drive device including the drive device can be made more compact. Furthermore, by providing the cooling fan on the flywheel as described above, the number of parts can be reduced, and by placing the intake duct facing the friction clutch, it is possible to cool the friction clutch, which has significant practical effects.

(Effects of the invention) As explained above, according to the air-cooled engine cooling system according to this invention, cooling air can be guided to the engine while preventing muddy water etc. from adhering to the engine. Moreover, it is possible to reduce the weight, and furthermore, it is possible to obtain the effect that the radiation of engine noise to the outside can be effectively suppressed.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; Fig. 1 is a side view of the tricycle, Fig. 2 is a plan view thereof, Fig. 3 is a side view with main parts of the drive section cut away, and Fig. 4 is a side view of the tricycle. 3 is a cross-sectional view taken along line 4-4, and FIG. 5 is a cross-sectional view taken along line 5-5 in FIG. In the drawing, 35 is a crankshaft, 43 is an axle, 20 is a wheel, 31 is an engine, 53 is a cooling fan, and 56, 55, 32f, and 32j are ducts.

Claims (1)

[Claims for Utility Model Registration] An engine 31 is arranged between two drive wheels 20, 20, these drive wheels 20, 20 and the engine 31 are covered with a fender 21, and a cooling air duct 55 is provided around the engine 31. A crankshaft 35 is installed in the cooling air duct 55.
In an air-cooled engine cooling device in which outside air is forcibly guided through an outside air intake duct 56 by a cooling fan 53 provided in the outside air intake duct 56, the cooling fan 53 is provided in the outside air intake duct 56. A crank case 32 is provided between the drive wheel 20 on the side and the engine 31, and is provided on the side where the cooling fan 53 is provided and is located on the outside of the crankshaft 35 in the longitudinal direction.
An outer wall 32e is provided in the outer wall 32e, and an opening 32g is provided inside the outer wall 32e and is opened substantially upward in the radial direction of the cooling fan 53, is connected to the outside air intake duct 56, and guides outside air into the cooling air duct 55. A partition wall 21a is provided between a portion of the fender 21 that covers the drive wheels 20 and a portion that covers the engine 31.
hangs down from the partition wall 21a and the outer wall 5 of the outside air intake duct 56.
4b and partition wall 21a, outer wall 54b of outside air intake duct 56, and outer wall 32e of crankcase 32 to partition drive wheel 20 and engine housing. .