JPS6029635Y2 - 2-cycle engine intake device - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to an intake device for a two-stroke engine.

BACKGROUND ART Conventionally, an intake device as shown in FIG. 1 has been put into practical use in some two-stroke engines.

This device includes a suction passage 1 which is branched into a first suction passage 1 □ and a second suction passage 1 □, and a cylinder 3 is used to open and close the tip of the first passage 11 with a piston 2.
The tip of the second passage 1□ is opened into the crank chamber 4, and the lead bubble 5 is inserted into the opening.
It has a configuration with an attached.

The lead bubble 5 is opened and closed by the pressure difference between the inside and outside of the crank chamber 4, and is opened when the inside of the crank chamber becomes negative pressure.

Reference numeral 6 indicates a carburetor attached to the base end B of the suction passage 1.

However, in the conventional inhalation device, as shown in the figure, the tip opening A of the first suction passage 11 and the base end B of the suction passage 1 are arranged in a straight line S through the passage 1□. Since the air-fuel mixture is connected to the carburetor 5 through the passage 11,
This was accompanied by the phenomenon of being blown back to the side, and as a result, it was not possible to obtain early inlet timing.

Moreover, since the main stream of the air-fuel mixture sent out from the carburetor 6 is directed toward the passage 11, the differential pressure acting on the lead bubble 5 is low, and therefore the suction efficiency through the second passage 12 is not good. There were drawbacks.

In view of the above, the present invention aims to provide an intake device for a two-stroke engine that can suppress the blowback phenomenon as much as possible and can increase the differential pressure that acts on the lead bubble. .

Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings.

Note that among the symbols used in the following description, the same symbols as those shown in FIG. 1 refer to the same elements.

In the suction device for a two-stroke engine according to the present invention, as shown in an embodiment in FIG. and a branching portion C of the passageway 1 from the proximal end B.
It has a configuration in which the section leading to the second suction passage is oriented toward the 1° side of the second suction passage.

According to this configuration, the opening A of the first passage 1□ and the base end B of the passage 1 are not connected in a straight line, so that so-called blowback through the first passage 1□ is minimized. can be suppressed to

Furthermore, since the flow resistance of the passage from the base end B to the lead bubble 5 is reduced, a large differential pressure acts on the valve 5, increasing its opening degree.

Therefore, according to the intake device for a two-stroke engine according to the present invention, it is possible to improve the engine output, and it is possible to improve the poor response in the low rotation range, which is a drawback of this type of conventional intake device. I can do it.

Furthermore, since the carburetor is mounted higher than in the past, the gap between the carburetor and the surroundings of the engine is widened, and as a result, so-called mud clogging in the gap is reduced, and maintenance is also facilitated.

[Brief explanation of drawings]

Figure 1 is a longitudinal cross-sectional view showing the configuration of a conventional inhaler;
The figure is a longitudinal sectional view showing an embodiment of the inhaler according to the present invention. 1... Suction passage, 11... First suction passage, 12... Second suction passage, 2...
Zeston, 3... Cylinder, 4... Crank chamber, 5... Lead bubble, 6... Carburetor.

Claims (1)

[Scope of utility model registration request] It is provided with a suction passage 1 which is branched into a first suction passage 11 and a second suction passage 12 in the middle, and the tip of the first passage 1□ is opened and opened in a cylinder 3 so as to be opened and closed by a piston 2, In a two-stroke engine suction device having a configuration in which the tip of the second passage 1□ is opened into the crank chamber 4 and a reed valve 5 is attached to the opening, the proximal end B of the suction passage 1 is It is characterized in that it is located above the tip opening A of the first passage 11, and that the section from the base end B to the branching part C of the passage 1 is directed toward the second passage 1 □ side. Intake device for 2-stroke engine.