JPS6233962Y2 - - Google Patents

Description

[Detailed description of the invention] This invention has a cooling fan attached to the end of the crankshaft that protrudes from the top of the engine body, and a fuel tank installed above the cylinder head located on the side of the engine body. covering the cooling fan and the fuel tank with a bonnet from above;
This invention relates to an air-cooled engine configured to guide cooling air to the cylinder head using an air guide cover attached to the inner surface of the bonnet ceiling.

Conventionally, in engines with the above configuration, the bonnet and the fuel tank are arranged with an appropriate gap in order to prevent the bonnet and the fuel tank from coming into contact with each other due to engine vibration and causing noise. Some of the cooling air leaked out, reducing the effectiveness of cooling the cylinder head.

For this reason, it was naturally considered to fill the space between the bonnet and the fuel tank with a sealant, but this required a means to attach the sealant to the inner surface of the bonnet or the outer surface of the tank, and it was necessary to apply it in advance. There was also a risk that the sealing material that had been used could be damaged or peeled off during the assembly process.

The purpose of this invention is to facilitate the assembly and ensure a reliable sealing effect when sealing the gap between the bonnet and the fuel tank. An embodiment thereof will be described based on the drawings.

Fig. 1 shows the entirety of an air-cooled vertical shaft engine mounted on a small agricultural machine such as a walking tailor, and Fig. 2 shows its longitudinal side view.

The engine body 1 has a crankshaft 3 supported vertically in a crankcase 2, a single-cylinder cylinder part 4 on one horizontal side, and a flywheel 6 with a cooling fan 5 attached to the upwardly projecting end of the crankshaft 3. It has a configuration in which a recoil starter 7 is attached. A fuel tank 8 is provided above the cylinder portion 4.
is provided, and an air cleaner 9 and a muffler 10 are installed on both sides of the engine body 1.
Additionally, a bonnet 11 is provided that covers the flywheel 6 and fuel tank 8 from above.

A wind guide cover 12 for guiding the air generated by the cooling fan 5 to the cylinder part 4 is installed vertically on the inner surface of the ceiling part of the bonnet 11, and one end of the cylinder head cover 14 is attached to a mounting plate 13 provided at one end of the cover 12. are connected.

Also, the bonnet 11 and cylinder head cover 1
In order to prevent a portion of the cooling air from leaking out from the gap 15 between the bonnet 11 and the bonnet 11, a wind shielding plate 16 is attached to the inner surface of the bonnet 11.

Further, a thick plate-shaped elastic sealing material 18 made of urethane foam is inserted into the injection tube 17 of the fuel tank 8 from above, and a spacer collar 19,
The bonnet 11 and the rear cover 20 are fitted in sequence, and the whole is tightened and fixed together with nuts 21, and the elastic sealing material 18 is strongly compressed and clamped between the collar 19 and the upper surface of the tank 8.

Further, the elastic sealing material 18 is largely extended toward the cooling fan 5 side and is locally compressed and clamped between the bonnet 11 and the corner 8a of the fuel tank 8, so that the cooling air flows between the bonnet 11 and the tank 8. This prevents leakage from between the 8 and 8.

The present invention is constructed as described above, and when assembling the bonnet, the bonnet and tank can be connected by simply fitting and locking the thick plate-shaped sealing material into the tank injection tube and assembling each part. The sealing of the gap has been completed, and the assembly is extremely simple compared to the method of pasting a sealing material, and there is no fear of damaging the sealing material.

In addition, since the large sealing material is locally compressed and clamped between the bonnet and the corner of the tank, reliable sealing can be achieved without being affected by slight errors in the assembly position of the sealing material. Ta.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is an overall perspective view, FIG. 2 is a partially cutaway side view, and FIG. 3 is a second
The sectional view taken along the line A--A in the figure, and FIGS. 4 and 5 are the sectional view taken along the line B--B and the sectional view taken along the line C--C in FIG. 3, respectively. 1...Engine body, 3...Crankshaft, 4...
... Cylinder part, 5 ... Cooling fan, 8 ... Fuel tank, 8a ... Corner part, 11 ... Bonnet, 12
... Air guide cover, 17 ... Injection cylinder, 18 ... Elastic sealing material.

Claims (1)

[Scope of utility model registration request] A cooling fan 5 is attached to the shaft end of the crankshaft 3 that protrudes from the upper surface of the engine body 1, and a fuel tank 8 is installed above the cylinder portion 4 located on the side of the engine body 1. The fuel tank 8 is covered with a bonnet 11 from above, and an air guide cover 12 attached to the inner surface of the ceiling of the bonnet 11 guides cooling air to the cylinder portion 4, and an elastic seal is secured to the injection tube 17 of the fuel tank 8. The material 18 is attached to the bonnet 11 and the fuel tank 8.
An air-cooled engine characterized in that the engine is locally compressed and clamped between a corner 8a on the cooling fan 5 side.