JPH04123351U - vaporizer - Google Patents

Abstract

(57) [Summary] [Purpose] To suppress the generation of bubbles in the fuel in the float chamber,
Make the engine run smoothly. [Structure] A circumferential groove 2 is formed on the outer periphery of the valve shaft 15 of the fuel valve 13.
0, and this groove 20 retains the fuel flowing between the valve chamber wall and the valve shaft 15, thereby forming a sealing portion with the fuel between the valve chamber wall and the flow from the float chamber 6 to the valve chamber 11. This prevents air from entering into the fuel flowing out from the valve hole 10.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to improvements in float type vaporizers.

0002

[Conventional technology]

The above carburetor has a fuel passage provided in the carburetor body to supply fuel to the float chamber. A valve hole communicating with the fuel passage is provided at the opening on the float chamber side of the passageway, and a valve hole communicating with the fuel passage is connected between the valve hole and the float chamber. A communicating valve chamber is provided, and the valve moves up and down following the float to open the valve hole. By inserting a fuel valve that closes, the oil level in the float chamber changes according to the oil level in the float chamber. The fuel valve controls the opening and closing of the valve hole to maintain a constant oil level. (Mr. Kimiaki (Refer to Publication No. 55-22178)

0003

[Problems with conventional technology]

By the way, the fuel flowing out from the above valve hole flows into the gap formed between the valve chamber and the fuel valve. The fuel flows through the valve hole into the float chamber, but when the fuel flows out of the valve hole, the flow Because the air flowing in from the float chamber is drawn in, a large amount of air bubbles are generated in the fuel in the float chamber. This has the disadvantage that the engine rotation becomes unstable. This defect flows out from the valve hole. The faster the fuel flow rate, that is, the higher the engine speed, the more likely it is to occur. .

0004 This invention suppresses the generation of bubbles in the fuel and makes the engine run smoothly. purpose.

[0005]

[Technical means to solve problems]

In the present invention, fuel flows around the outer periphery of the valve shaft of the fuel valve, through a gap between the inner wall of the valve chamber and the valve shaft. A groove is provided that holds fuel and forms a seal between the valve chamber and the inner wall of the valve chamber. It is characterized by

[0006]

[Effect]

When the oil level in the float chamber decreases as the engine operates, the float moves downward, the fuel valve follows this and opens the valve hole, and fuel flows out from the valve hole. Ru. When this fuel flows through the gap formed between the valve chamber and the stem of the fuel valve, the Fuel is retained in the groove, and a fuel seal is formed between the groove and the inner wall of the valve chamber. this Since the seal portion blocks air flowing from the float chamber to the valve hole side, the valve This prevents air from getting mixed into the fuel flowing out of the holes, preventing air bubbles from forming in the fuel. will be stopped.

[0007]

【Example】

An embodiment of the present invention will be described below with reference to the drawings. Reference numeral 1 denotes a carburetor main body, and an intake passage 2 is provided to pass through the carburetor main body 1. A venturi 3 is provided in the center of the intake path 2. It's Venturi 3 again. A choke valve 4 is arranged in the intake passage 2 upstream of the venturi 3, and A throttle valve 5 is arranged at 2.

[0008] A float chamber 6 is formed on the lower side of the carburetor main body 1, and an upper The end opens to the venturi 3 of the intake passage 2, and the lower end opens to the venturi 3 of the intake passage 2, and the lower end opens to the venturi 3 of the intake passage 2. A main nozzle 8 communicating with the float chamber 6 below the oil level is arranged. In addition, the above-mentioned The converter main body 1 is provided with a fuel passage 9 for supplying fuel to the float chamber 6. 9 has a valve hole 10 communicating with the fuel passage 9 and a valve hole 10 at the opening on the float chamber 6 side. and a valve chamber 11 communicating between the float chamber 6 and the float chamber 6 are provided. Inside this valve chamber 11 , a fuel valve 13 that moves up and down following the float 12 is inserted, and the fuel valve 13 is inserted into the valve hole 10. Opening/closing is controlled according to the oil level.

[0009] A valve body 14 is provided at the top of the fuel valve 13, and a valve shaft is provided below the valve body 14. 15 is formed. The valve shaft 15 has a guide portion 16 having a slightly smaller diameter than the inner diameter of the valve chamber 11. A flow path 17 is formed between the guide portions 16. Outside of this valve stem 15 The periphery contains fuel flowing through the flow path 17 and the gap between the guide portion 16 and the valve chamber wall 18. A groove 20 is formed to hold the fuel and form a fuel seal 19 with the valve chamber wall 18. It is provided.

0010 3 and 4 take a fuel valve 13 with a valve shaft 15 of 8 mm in length as an example, and show the groove 2. It is a characteristic diagram which shows the generation|occurrence|production of a bubble when the position and width of 0 are changed, respectively. Figure 3 shows when the width M of the groove 20 is fixed at 1.5 mm and its position is changed in the vertical direction. It shows the change in the bubble generation rate, and the distance from the upper end of the valve stem 15 to the upper edge of the groove 20. The rate of bubble generation decreases in the range of distance L from around 1 mm to around 4 mm. In addition, FIG. 4 shows the position of the groove 20 at the lowest bubble generation rate shown in FIG. That is, the distance L from the upper end of the valve stem 15 to the upper edge of the groove is fixed at around 1.5 mm, and the groove This shows the change in the bubble generation rate when the width M is changed, and the groove width M is 1 mm. It can be seen that the rate of bubble generation decreases in the range from the vicinity to around 3 mm. Note that the bubble generation rate shown in FIGS. 3 and 4 above is that of the conventional fuel valve 13 without the groove 20. This figure is based on the bubble generation rate being 100%.

[0011] The operation of the above embodiment will be explained below. When the oil level in the float chamber 6 decreases as the engine operates, the oil will flow. The valve 12 moves downward, and following this, the fuel valve 13 opens the valve hole 10. Fuel flows out from 0. This fuel is formed between the valve chamber 11 and the valve shaft 15 of the fuel valve. When the fuel flows through the gap between the grooves 20 and the inner wall 18 of the valve chamber, the fuel is retained in the groove 20 and the fuel is A seal portion 19 made of a material is formed. This seal part 19 allows the float chamber 6 to Since the air flowing into the valve hole 10 side is blocked, the fuel flowing out from the valve hole 10 is Air is not mixed in and the generation of bubbles in the fuel is prevented.

0012

[Effect of the idea]

As detailed above, according to the present invention, a circumferential groove is provided in the shaft portion of the fuel valve. The fuel held between this groove and the peripheral wall of the valve chamber causes the fuel to flow in from the float chamber. This prevents air from getting mixed into the fuel flowing out from the valve hole. This prevents air bubbles from forming in the fuel and allows the engine to run smoothly. Ru.

[Brief explanation of drawings]

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

FIG. 2 is an enlarged sectional view showing the main parts of the present invention.

FIG. 3 is a characteristic diagram showing the bubble generation situation when changing the position of the groove of the present invention.

FIG. 4 is a characteristic diagram showing the bubble generation situation when the groove width of the present invention is changed.

[Explanation of symbols]

1 Vaporizer body 6 Float chamber 10 Valve hole 11 Valve chamber 13 Fuel valve 15 Valve stem 20 groove

Claims (1)

[Scope of utility model registration request] Claim 1: A valve hole communicating with the fuel passage and a valve communicating between the valve hole and the float chamber are provided at the float chamber side opening of the fuel passage provided in the carburetor body to supply fuel to the float chamber. In the carburetor, the valve shaft of the fuel valve is provided with a chamber, a fuel valve interlocked with a float is vertically movably inserted into the valve chamber, and the valve hole is opened and closed by vertical movement of the fuel valve. A carburetor, characterized in that a groove is provided on an outer periphery to hold fuel flowing through a gap between the inner wall of the valve chamber and the valve shaft, and to form a seal between the inner wall of the valve chamber and the fuel.