JPH045690Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) This invention provides a dustproof screen between an engine body equipped with a cooling air intake and a fuel tank disposed near the cooling air intake. The present invention relates to a small air-cooled engine equipped with an air-cooled engine.

(Prior art) Generally, in the case of a working machine such as a brush cutter where the engine is installed at a relatively low position, a large amount of grass clippings, garbage, etc. can enter through the cooling air intake port of the engine, causing damage to the inside of the cylinder cover and cylinder fins. It often builds up between them and causes overheating. As a countermeasure against this problem, it has been conventionally practiced to attach a dustproof screen to the cooling air intake.

However, as shown in FIG. 1, in an engine that has a fuel tank below the engine and is provided with reverse cooling, it is extremely difficult to attach the dustproof screen to the cooling air intake. That is, in this type of engine, a fuel tank 23 is fixed to the lower part of the engine body 11, and a cooling fan 19 is provided on one side 15 of the engine body 11, and cooling air A is supplied to the engine body 11 and the fuel. The cooling air intake 2 at the bottom of the engine body 11 passes between the tank 23 and the cooling air intake 2 at the bottom of the engine body 11.
7 toward the one side 15, turned back by the cooling fan 19, and directed toward the other side 29 to cool the cylinder 13 at the top of the engine body. Since the space between the lower part of the engine body 11 where the air intake port 27 is provided and the fuel tank 23 is compressed, it is extremely difficult to attach a dustproof screen to the cooling air intake port 27.

Therefore, conventionally, for example, by integrally forming a guard body with a fuel tank and fixing this fuel tank to an engine body, the guard body is disposed opposite to the cooling air intake port of the engine body, and the guard body A device that covers the cooling air intake is known (see Japanese Utility Model Application Publication No. 163631/1983).

However, according to the above configuration, since the guard body is integrally formed with the tank, it is not possible to form the guard body into any mesh, etc., or to change only the specifications of this guard body by replacing the guard body. was impossible.

(Purpose of the invention) This invention makes it possible to easily and reliably install a dustproof screen between the engine body and the fuel tank, and also to secure a certain gap between the engine body and the fuel tank, thereby improving cooling performance. The compact air-cooled design allows for maintenance of the fuel tank, while also making it possible to change the specifications of the dust-proof screen without changing the tank.Furthermore, the cooling air intake provided in the engine body can be effectively dust-proofed, and the fuel tank can be mounted more firmly. The purpose is to provide engines.

(Structure of the invention) In order to achieve the above object, the small air-cooled engine according to the invention maintains a predetermined gap between the dustproof screen that covers the cooling air intake of the engine body, the fuel tank, and the dustproof screen. A foot member and a mounting member to which a fixture for pressing and fixing the fuel tank to the foot member are attached to the engine body, and the fuel tank is mounted on the mounting member via the fixture. It is characterized by:

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

Fig. 2 shows a small air-cooled engine for a brush cutter.
, a cylinder 13 , and a fan case 14 . A flywheel 16 and a centrifugal clutch 17 are attached to one end of a crankshaft (not shown) protruding from the crankcase 12 to one side 15, and an output shaft to the cutting blade is provided via the centrifugal clutch 17. 18 is connected to the crankshaft. The flywheel 16 includes a cooling fan 19
The flywheel 16 and the ignition coil device 21 installed opposite to the flywheel 16 are connected to the fan case 1.
It is housed in 4.

A recoil starter 22 is attached to the other side of the crankcase 12, and a fuel tank 23 is located near a cooling air intake 27 provided in the engine body 11, for example, below the engine body 11.
The fuel tank 23 is attached to a tank mount 24 attached to the engine body 11 via a band-shaped fixture 25.

Figure 3 is an exploded perspective view of the engine shown in Figure 2, viewed from below.
1 has a cooling air intake 27 at the bottom through which engine cooling air A is drawn, and also has cooling air intakes 28 on both sides, and the cooling air A is drawn from the cooling air intakes 27 and 28. , taken in toward one side 15 shown in FIG.
9, and after cooling the cylinder 13, it is discharged to the outside.

As shown in FIG. 3, the tank pedestal 24 is
Foot member 31 mounting member, e.g. and mounting hook 32
A pair of sheet metal brackets 33 formed by bending the
34 and a dustproof screen 35 that covers the cooling air intake 27 at the lower part of the engine body 11, the dustproof screen 35 is sandwiched between the two brackets 33 and 34, and spot welded at points S1 and S2. By doing so, both brackets 33 and 34
and a dustproof screen 35 are fixed to each other. Further, a reinforcing member 36 is spot-welded to the foot member 31, and a vibration-proofing cover 3 is attached to the tip.
7 is fitted. The dustproof screen 35 has a mesh body 35b fixed to a frame body 35a by spot welding.

The thus obtained tank mount 24 is attached to two screw holes 40 drilled in the connection surface of the crankcase 12 with the recoil starter 22, and two screw holes drilled in the stepped portion of the crankcase 12 on the output shaft 18 side. 40 with bolts 41. At this time, side dustproof screens 42, 42 are separately prepared to cover the cooling air intake ports 28 on both sides of the engine body 11, and these side dustproof screens 42 are prepared separately.
2 together with the bolts 41 mentioned above. In order to securely fix the side dustproof screen 42,
Screw hole 4 provided near the cooling air intake port 28
3 is also fastened with a bolt 41. The side dustproof screen 42 also has a mesh body 4 on the frame body 42a.
2b are fixed by spot welding.

In this way, the tank mount 24 is attached to the engine body 11.
Fig. 4 shows what is attached to it. When the fuel tank 23 is attached as shown in FIG. is held, while the fuel tank 23 is attached to the leg member 31 by the mounting tool 25 that is locked to the mounting hook 32.
It is pressed against and fixed to the tank mount 24.

In the above configuration, the cooling air intakes 27 and 28 shown in FIG. 3 are covered by the dustproof screen 35 and the side dustproof screen 42, as shown in FIG. It is sufficiently dust-proof when introduced into the engine body 11 through the intake ports 27 and 28. Further, as is clear from FIG. 2, since a predetermined gap 44 is secured between the dustproof screen 35 and the fuel tank 23 by the leg members 31, the cooling air A is not obstructed by the fuel tank 23. The above gap 44
Since the cooling air is smoothly introduced into the engine body 11 from the lower cooling air intake port 27 through the cooling air intake port 27, the cooling performance of the engine is maintained at a high level. Further, since the fuel tank 23 is pressed against the foot member 31 by the mounting tool 25 that is engaged with the mounting hook 32, the fuel tank 23 is firmly fixed to the tank frame 24.

Moreover, the dustproof screen 35 is attached to the tank mount 24.
Since it is provided in
There is no need for any parts or work to attach the device to the device.

Here, the mesh body 35 of the dustproof screens 35, 42
The area of each screen b and 42b should be large enough to prevent it from becoming clogged with dust, straw, etc. in a short period of time, based on the engine operating time based on actual work. In addition to setting the area and position so that the accumulation of dust, straw, etc. on the nets 35b and 42b is visible from the outside of the engine, and the user can clean it if he notices the accumulation. It is preferable to keep it.

In the above embodiment, the dustproof screen 35 was fixed to the brackets 33, 34, but unlike this, the dustproof screen 35 was fixed to the brackets 33, 34.
The dustproof screen 35 may also be fastened to the engine body 11 together with bolts 41 when the tank mount 24 is attached to the engine body 11.
Can be installed on 1. Of course, dustproof screen 35
may be fixed to the engine body 11 directly or via a member other than the brackets 33 and 34, with a predetermined gap maintained between the cooling air intake port 27 and the cooling air intake port 27.

Further, the side dustproof screen 42 may be formed integrally with the dustproof screen 35.

(Effects of the invention) As explained above, according to this invention, the cooling air intake provided in the engine body can be effectively dust-proofed with a dust-proof screen, and foreign matter such as grass clippings and dirt can accumulate inside the engine and cause overheating. Not only can this prevent this from happening, but since the dustproof screen is fixed to the engine body before the fuel tank is fixed to the engine body, it is easy to attach the dustproof screen to the engine body. Not only is it easy, but it is also possible to change the specifications of the dustproof screen without changing the tank. In addition, since the foot members are fixed to the engine body, by bringing them into contact with the opposing surface of the fuel tank, a certain gap can be secured between the engine body and the fuel tank, and the flow of cooling air is not obstructed. Therefore, cooling performance is maintained at a high level. Further, the fuel tank can be easily and securely mounted on the engine body since the fuel tank can be attached to the engine body after the dustproof screen is attached to the attachment member fixed to the engine body via a fitting such as a tightening band or a screw body.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing a conventional example, Fig. 2 is a longitudinal sectional view showing an embodiment of the invention, Fig. 3 is an exploded perspective view seen from the direction of the arrow in Fig. 2, and Fig. 4 is a longitudinal sectional view showing an embodiment of the invention. 3
FIG. 3 is a perspective view of the engine mount shown in the figure attached to the engine body. 11...Engine body, 23...Fuel tank,
25... Mounting tool, 27... Cooling air intake port, 31
... Leg member, 32 ... Mounting member, 33, 34 ...
Bracket, 35... Dustproof screen, 44...
Gap, A...Cooling air.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A small air-cooled engine comprising a dustproof screen disposed between an engine body equipped with a cooling air intake and a fuel tank disposed near the cooling air intake. a dustproof screen fixed to the engine body and covering the cooling air intake; and a dustproof screen fixed to the engine body and in contact with the fuel tank to maintain a predetermined distance between the fuel tank and the dustproof screen. a foot member fixed to the engine body and to which a fitting for pressing and fixing the fuel tank against the foot member is removably fixed, and the fuel tank is attached to the mounting member. A small air-cooled engine characterized by being equipped with a (2) A small air-cooled engine according to claim 1, wherein a dustproof screen covering a cooling air intake is fixed to a bracket integrally formed with a foot member and a mounting member.