JPS6128040Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an air cleaner that is attached to the inlet of a carburetor and filters the air and causes the air to be drawn into the inlet.

Generally, in a two-cycle engine, the carburetor, which communicates the carburetor with the crank chamber, opens at approximately the highest position of the piston. At this time, the pressure inside the crankcase is reduced to negative pressure, so atmospheric air is sucked in from the air cleaner, mixed with vaporized fuel through the carburetor, and sucked into the crankcase. When the piston begins to descend from its highest position, the air below the piston is rapidly displaced, causing some momentary flow back into the carburetor. This phenomenon is called blowback, and as a result of this blowback, the fuel-containing air-fuel mixture collides with the filter of the air cleaner, causing fuel to adhere to the filter and dust to adhere to it, which accelerates the clogging of the filter. It was becoming. For this reason, conventionally,
A shutter plate is installed in the air cleaner in front of the intake port of the carburetor, and the air-fuel mixture that is momentarily blown back collides with the shutter plate to buffer it and prevent the air-fuel mixture from colliding with the filter. Since this shutter plate was manufactured from a metal plate or the like separately from the air cleaner, it took time and effort to assemble, and also had the disadvantage that it was structurally complex and could not be manufactured at a low cost.

In addition, small portable engines need to be made as compact as possible in order to improve workability, and it is particularly undesirable for the air cleaner to protrude outward from the engine.

The present invention was devised to solve the above-mentioned drawbacks.It is compact, easy to operate, easy to assemble and maintain, has a simple structure and can be manufactured at low cost, and has a filter that can blow back the air-fuel mixture. The purpose of the present invention is to provide an air cleaner that can prevent dirt and clogging and maintain a good air flow at all times.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

In the figure, 1 is a main body case fixed to the intake port 5 of the carburetor 3 by bolts 7, 7, 9 is a cover that engages with the main body case 1 and forms a chamber 11 inside, and 9 is a cover that engages with the main body case 1 and forms a chamber 11 inside. is fixed to the carburetor 3 together with the main body case 1. A shutter plate 13 is provided facing the intake port 5, and is integrally formed with the main body case 1 from synthetic resin or the like. The shutter plate 13 is supported by struts 17, 17, . . . so as to form a space 15 on the suction port 5 side. Reference numeral 19 denotes a filter body made of a porous material such as urethane foam, which is sandwiched between the pillars 21, 21 protruding from the inner surface of the cover 9 and the shutter plate 13, and partitions the chamber 11 and the space 15. It's on. Reference numeral 23 is a tubular intake passage that communicates the chamber 11 with the atmosphere, and is used to muffle the intake air.

Note that the shutter plate 13 is connected to the filter body 19.
are located on a plane supported by the pillars 17, 17, . . . , and the filter body 19 is provided in a direction perpendicular to the axis of the suction port 5.

In the above embodiment, atmospheric air is sucked into the chamber 11 through the intake passage 23 by the suction force of the engine cylinder (not shown), passes through the filter 19 to remove dust, and then passes through the space 15. It is sucked into the suction port 5. The blowback of the air-fuel mixture at the moment when the piston begins to descend is buffered by colliding with the shutter plate 13 through the space 15, so the filter 19
The piston descends and the blowback is closed.

Since the present invention has the configuration as described in the claims, it has a simple structure, is easy to assemble, and can be manufactured at low cost.Moreover, it prevents the filter body from becoming dirty and clogged due to air-fuel mixture blowing back. The flow can be maintained well.

In addition, it does not protrude to the side of the engine, making it compact and easy to handle.Furthermore, even when the engine cylinder is used in a horizontal position, the intake passage is horizontal, preventing rainwater from entering. There is no.

Furthermore, the inner surface of the filter body is supported by a shutter provided at a position facing the suction port and a column supporting the shutter, and a space is formed between the filter body and the suction port. Therefore, the air is throttled by the intake passage, enters the chamber, is further throttled by the resistance of the filter, expands again in the space, and is sucked into the engine from the intake port, and this two-degree throttle The expansion action buffers the pulsation of the intake air caused by the reciprocating movement of the engine piston, thereby effectively muffling intake noise.

It should be noted that the present invention is not limited to the above-mentioned embodiments, but can be implemented in other embodiments as well. Further, the symbols shown in the claims do not limit the technical scope of the present invention.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of one embodiment of the present invention, FIG. 2 is a front sectional view taken along the - line in FIG. 1, and FIG. 3 is a plan sectional view taken along the - line in FIG. Explanation of the symbols representing the main parts of the drawing, 1...
Main body case, 3... vaporizer, 5... inlet, 9...
... Cover, 11 ... Chamber, 13 ... Shutter plate, 15 ... Space, 17 ... Support, 19 ...
Filter body, 23...Intake path.

Claims (1)

[Scope of utility model registration request] A filter body 19 is provided inside the main body case 1 and is perpendicular to the axis of the suction port 5 of the vaporizer 3. A cover 9 that supports the inner surface of the filter body 19 and engages the filter body 19 with the main body case 1.
a shutter plate 13 facing the inlet 5 on the plane;
is formed integrally with the main body case 1, and a chamber 11 formed in the cover 9 is connected to the filter body 19.
The chamber 11 is provided in communication with the space 15 through a horizontal tubular intake passage 23 that opens toward the engine. Air cleaner.