JPH05195891A - Air suction device for internal combustion engine - Google Patents

Abstract

PURPOSE:To cool a carburetor and improve performance of the carburetor and a filter by setting flow of air supplied to the carburetor from the upper part to the lower part, and providing an air passage communicated to a cooling fan chamber on the lower part of the filter arranged around the carburetor chamber. CONSTITUTION:A passage 5 with which air flow from the upper part to the lower part is generated by utilizing suction negative pressure generated in the cooling fan chamber of an internal combustion engine is provided. The passage 5 is provided around a carburetor chamber 4 so as to cool the carburetor chamber 4. The face of a filter 6 for supplying purified air to the carburetor chamber 4 is arranged along the passage 5 in the up and down direction, so as to generate air flow in the direction along the face of the filter 6. At the same time, air flow into the carburetor chamber 4 is directed in the crossing direction to the face of the filter 6, and dust in the passage 5 is dropped along the face of the filter 6. As a result, the carburetor chamber 4 can be effectively cooled, and filtering performance of the filter 6 is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air intake device for an internal combustion engine.

[0002]

2. Description of the Related Art Generally, an air intake device for an internal combustion engine is
In many cases, the cleaner chamber and the carburetor chamber were arranged adjacent to each other, purified air from which dust had been removed was introduced into the carburetor chamber, and the filter was regularly replaced or the filter was replaced by checking the dirt of the filter. .. Since this type of air intake device for an internal combustion engine requires complicated filter replacement, various devices have been devised that do not require frequent filter replacement with a simple structure, but have sufficient performance and practicality. There has never been an air intake device for various internal combustion engines.

[0003]

SUMMARY OF THE INVENTION The present invention is to obtain a novel structure which is not found in the conventional air intake device for an internal combustion engine, and utilizes the suction negative pressure generated in the cooling fan portion of the internal combustion engine. It is therefore an object of the present invention to provide an air intake device for an internal combustion engine, which can cool the vaporizer and improve the vaporizer and filter performances.

[0004]

That is, an air intake system for an internal combustion engine according to the present invention uses an intake negative pressure generated in a cooling fan section of the internal combustion engine to generate an air flow from above to below. A passage is provided, the passage is provided around the vaporizer chamber to cool the vaporizer chamber, and a face of a filter for supplying purified air to the vaporizer chamber is arranged vertically along the passage. The air flow in the direction along the surface of the filter and the air flow into the carburetor chamber in a direction intersecting the surface of the filter to remove dust in the passage from the surface of the filter. It is characterized in that it is configured to drop along.

[0005]

Therefore, the air intake system for the internal combustion engine according to the present invention is provided with the passage for causing the flow of air from the upper side to the lower side, and the passage is provided around the carburetor chamber and is purified in the carburetor chamber. The surface of the filter for supplying the air is arranged vertically along the passage, and the suction negative pressure generated in the cooling fan portion of the internal combustion engine is used to move the air flow from above along the surface of the filter. Let it go down,
The surroundings of the carburetor chamber are cooled, and the flow of air in the vertical direction causes dust to drop along the surface of the filter, and also facilitates the supply of air to the carburetor.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The drawings show an air intake device in a chain saw internal combustion engine according to this embodiment.
The front of the main body B of the chain saw is shown in cross section, and the outside air is taken in from the inlet 1 which is arranged rearward on the upper part of the main body 1 far from the saw chain guide bar 11. As shown in FIGS. 1 and 2, the inlet 1 communicates with an intake silencer 3 equipped with an appropriate number of muffler tubes via an upper air passage 2 that communicates horizontally forward with the intake silencer 3
Is connected to a vertical passage 5 that causes a flow of air to be supplied to the carburetor chamber 4 disposed above the front portion of the main body B from downward to downward. The vertical passage 5 extends along the surface of a filter 6 for supplying purified air to the vaporizer chamber 4, and a lower air passage 7 is provided below the vaporizer chamber 4 below the filter 6. The air flow is formed and communicated with the cooling fan chamber 8. The cooling fan chamber 8 has a fan 9 for cooling an internal combustion engine (not shown) as shown in FIG. 3, and the suction negative pressure generated on the suction side of the cooling fan chamber 8 is used to move to the carburetor chamber 4. A flow of air to be supplied is generated from above to below. FIG. 4 shows another embodiment, in which the air inlet 10 is provided on the upper side of the main body B on the side opposite to the guide bar 11. The intake silencer 3 also serves as a seal between the carburetor chamber cover 13, the filter 6, the carburetor chamber 4, and the passages 2, 5 and 7.

Therefore, an air flow from the upper side to the lower side is generated in the direction along the surface of the filter 6, and the dust is dropped in the vertical direction along the surface of the filter 6 while the air is introduced into the carburetor chamber 4. The flow is carried out in the direction intersecting the plane of the filter, and dust-free intake air is provided into the carburetor chamber.
Further, the air flow that flows by utilizing the negative suction pressure generated in the cooling fan chamber 8 flows around the vaporizer chamber 4 and cools the vaporizer chamber. In this case, it is effective to form the air passage in a substantially U-shape that surrounds the carburetor chamber, as in the illustrated example.

[0008]

As is apparent from the above description, according to the structure of the present invention, since a unique air flow passage is provided by utilizing the negative suction pressure generated by the cooling fan portion of the internal combustion engine, a special cooling fan is provided. It is possible to effectively cool the carburetor chamber without using, etc. and improve the filtration performance of the filter by dropping dust along the surface of the filter by the flow of air in the vertical direction along the filter surface, The purified air without dust is supplied to the carburetor chamber, and the suction negative pressure generated in the intake and cooling fan of the carburetor can be used to facilitate the supply of air to the carburetor. Can play.

[Brief description of drawings]

FIG. 1 is a side view of an essential part showing an air intake device for a chain saw that is an embodiment of the present invention.

FIG. 2 is a plan view of FIG. 1 showing a cross section of a main part of an upper portion.

FIG. 3 is a plan view of FIG. 1 showing a cross section of a main part of an intermediate portion.

FIG. 4 is a plan view in which a main part of an upper portion showing an air introduction port according to another embodiment of the present invention is sectioned.

[Explanation of symbols]

 1 Air Inlet 2 Air Passage 3 Silencer 4 Vaporizer Chamber 5 Air Passage 6 Filter 7 Air Passage 8 Cooling Fan Chamber 9 Cooling Fan 10 Air Inlet

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hirosaki Kawasaki, 1-7 Suehiro-cho 2 Ome-shi, Tokyo 2 Kyoritsu Co., Ltd. (72) Inventor Tsutomu Ogata 1-7 2 Suehiro-cho Ome-shi, Tokyo Share company Kyoritsu

Claims (3)

[Claims] 1. A carburetor chamber is provided which is provided with a passage for generating a flow of air downward from above by utilizing a negative suction pressure generated in a cooling fan portion of an internal combustion engine, the passage being provided around the carburetor chamber. The surface of the filter for cooling and supplying purified air to the carburetor chamber is arranged vertically along the passage to generate the air flow in the direction along the surface of the filter. An air intake of an internal combustion engine, characterized in that the flow of air into the carburetor chamber is made to intersect with a surface of the filter to drop dust in the passage along the surface of the filter. apparatus. 2. The passage is formed in a substantially U-shape so as to surround the carburetor chamber.
Air inhaler. 3. The air suction device according to claim 1, wherein an air intake silencer is provided at an air inlet portion of the passage.