JP2550913Y2 - Venturi mixer - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a venturi mixer for a gas engine.

[0002]

2. Description of the Related Art In such a conventional venturi mixer, as shown in FIGS. 4 and 5, a gas inlet portion for mixing a gas G into an air flow A has, for example, a pair of gas inlets perpendicular to a central axis C of the venturi 10. It was constituted by slits 11 and 11. In the conventional structure in which the gas inlets are the slits 11 and 11, as shown in FIG. 3, when the air-fuel mixture flow rate changes, the air ratio changes as shown by a characteristic b, and a defect such as incomplete combustion occurs only with the venturi mixer. Occurs. Therefore, another flow control device was required.

Further, Japanese Utility Model Publication No. 26-10403 discloses a mixer having a slit inclined in a cutting line direction so as to generate a vortex on the downstream side of the throat of a venturi. However, in such a known technique, the amount of air and gas (mixture flow rate) is almost the same as in a diesel engine in which the injected ignition oil ignites spontaneously according to the temperature of the highly compressed air-fuel mixture to ignite the air-fuel mixture and cause an explosion. Although it is good to be constant, there is the above-mentioned drawback when the change in the air-fuel mixture flow rate is large as in a gas engine. The purpose of the present invention is to generate a vortex in the venturi section to improve the mixing of air and fuel, and cannot solve the problems of the present application described later.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a venturi mixer capable of reducing a change in an air ratio due to a change in a flow rate of an air-fuel mixture and thereby improving the efficiency of a gas engine.

[0005]

According to the present invention, in a venturi mixer in a gas engine, a gas inlet for mixing gas into an air stream is parallel to and includes the central axis of the venturi. It is composed of a plurality of slits arranged in a plane, which are located immediately downstream of the throat of the venturi.

[0006]

[0007]

Therefore, the gas flows into the fluid passing through the venturi at a right angle from the slit disposed in the plane including the central axis of the venturi, so that the fluid does not vortex and can be passed with a small pressure loss. Also, since the gas flowing from each slit does not interfere,
Variations in the air ratio with changes in fluid flow are improved. Therefore, in the present invention, by simply providing a pair of slits, in a gas engine having a large change in the mixture flow rate,
Efficient operation can be performed at high speed and high load or at low speed and low load. Further, since a control device is not required and the configuration is simple, a practical gas engine can be obtained.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In FIGS. 1 and 2, a plurality (four in the illustrated example) of slits 3 to 3 parallel to the central axis C of the venturi 1 are formed on the downstream side of the throat portion 2 of the venturi 1 in a cross shape. It is arranged in. And these slits 3-3
Is connected to a gas supply pipe (not shown).

The outer diameter D of the venturi 1 is, for example, 47
mm, the length L is, for example, 54 m, the distance L1 from the front end of the throat portion 2, for example, 18 mm, the inner diameter D1 of the throat portion 2 is, for example, 24 mm, while the length S of the slit 3 is,
For example, the width w is 11 mm, and the width w is 4 mm, for example.

In the illustrated embodiment constructed as described above,
Even if the air-fuel mixture flow rate changes as shown in FIG. 3, the change in the air ratio is suppressed to a small value as indicated by the characteristic a. From the experimental results shown in the figure, it can be seen that, for the same change in the air-fuel mixture flow rate, the change in the air ratio is suppressed to about 1/4 as compared with the conventional case.

[0012]

As described above, according to the present invention, the following excellent effects can be obtained. (A) Even if the air-fuel mixture flow rate changes, the change in the air amount can be made small, contributing to the improvement of the efficiency of the gas engine as a venturi mixer of the gas engine. (B) An inexpensive Venturi mixer with a simple structure can be obtained without requiring a special flow rate adjusting device.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a venturi showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along line XX of FIG. 1;

FIG. 3 is an air-fuel ratio-air ratio characteristic diagram showing an effect in comparison with a conventional example.

FIG. 4 is a side sectional view showing a venturi of a conventional mixer.

FIG. 5 is a sectional view taken along line XX of FIG. 4;

[Explanation of symbols]

 A: Air flow C: Venturi central axis G: Gas 1, 10: Venturi 2: Throat 3, 11, Slit 4: Enlarged part

Claims (1)

(57) [Scope of request for utility model registration] In a venturi mixer in a gas engine, a gas inlet for mixing gas into an air flow is formed by a plurality of slits arranged in a plane parallel to a central axis of the venturi and including a central axis of the venturi. Venturi mixer characterized in that it is constructed and the slit is located immediately downstream of the throat of the Venturi.