JPS62113854A - Fuel control device for carburetor - Google Patents

Abstract

PURPOSE:To make it possible to accurately open or close plural fuel passages by constituting a valve body which opens and closes plural fuel passages with a valve plate fixed to the tip of a solenoid valve movable rod and a plural seal members facing to the opening end of each fuel passage. CONSTITUTION:A valve body 34 consists of a plate-shaped valve plate 37 fixed to the tip of the movable rod 36 of a solenoid valve 35 and two seal members 38 separably attached to opening ends 13a, 14a, in a device whose valve body 34 closing the opening ends 13a, 14a of plural fuel jets 13, 14 by means of a spring energizing force is opened by the excitation of the solenoid valve 35 installed on the side wall 31 of a float chamber in a carburetor main body 1. Then each seal member 38 is fixed to a seal installation hole 37a where one side of the valve plate 37 is released in a biased position against the center of a movable rod 36. Hereby each of opening end 13a, 14a can be closed steadily.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a carburetor, such as a composite type carburetor, in which a plurality of fuel passages are communicated with a float chamber. This invention relates to a fuel control device that is equipped with a valve body that can be closed at the same time and is used to prevent overspeeding of an engine and protect a catalyzer in an exhaust system.

<Prior Art> Conventionally, a fuel control device for a carburetor is known that uses a solenoid valve to close a plurality of fuel passages communicating with a float chamber to cut off fuel supply to an intake passage. Since a plurality of fuel passages are closed by one solenoid valve, for example, a gathering chamber is formed that communicates with the plurality of fuel passages and a float chamber, and the opening of the gathering chamber is closed by one valve body, or A structure is adopted in which a diaphragm is operated in the gathering chamber to close the upstream openings of the plurality of fuel passages (Utility Model Application No. 54-56032, Utility Model Application No. 57-2678).

By the way, in the above conventional structure, in addition to the float chamber, there is a need for a collection chamber in which fuel is constantly stored, and the fuel passage becomes complicated, so vapor generated in the fuel due to high temperatures during engine operation is discharged. This may cause inconveniences such as the fuel supply not being carried out smoothly and the engine output being adversely affected.

<Problems to be solved by the invention> In order to ensure prompt discharge of vapor generated at high temperatures without complicating the fuel passages, a gathering chamber is not provided between the multiple fuel passages and the float chamber. Preferably, the upstream opening ends of the plurality of fuel passages are provided in the float chamber.

However, when the above-mentioned valve structure is applied to a float chamber, the structure requires that a valve mechanism such as a diaphragm spring operates within the float chamber, and that the opening ends of multiple fuel passages are closed by a flat valve body. has been taken,
According to this structure, the valve mechanism such as the diaphragm interferes with the float, and if this interference is avoided, the size of the float is significantly restricted, and the difference in level between the end faces of the opening end and the error in the flatness of the valve body There is a problem that the opening end and the valve body do not come into close contact with each other, resulting in an unwanted inflow of fuel, which adversely affects engine performance, making it difficult to implement the above-described valve structure.

In view of these problems in the prior art, the main object of the present invention is to provide a vaporizer that can simultaneously seal multiple fuel passages with a single solenoid valve, with an extremely simple structure that does not require a special chamber such as a gathering chamber. The purpose of the present invention is to provide a fuel control device for a fuel tank.

<Means for Solving the Problems> According to the present invention, the present invention provides a method for closing a plurality of fuel passages communicating with the float chamber using a solenoid valve to cut off fuel supply to the intake passage. The fuel control device for a carburetor includes a valve plate fixed to a movable rod end of a solenoid valve, and a valve plate arranged in correspondence with an upstream opening end of a plurality of fuel passages opening into the float chamber. This is achieved by providing a fuel control device for a carburetor, which is characterized by having a valve body made up of a plurality of seal members.

<Operation> In this way, the upstream opening ends of the multiple fuel passages are opened directly into the float chamber, and a valve body with multiple sealing members fixed to the valve plate for sealing the multiple opening ends is provided at the tip of the solenoid valve movable rod. This makes it possible to simplify the fuel passage. Further, it is possible to reliably close the opening ends of the plurality of fuel passages without requiring high precision, and it is possible to avoid adverse effects on engine performance due to unwanted fuel inflow.

<Embodiments> The present invention will now be described in detail with reference to specific embodiments with reference to the accompanying drawings.

FIG. 1 shows the entire carburetor to which the fuel control device according to the present invention is applied, and the carburetor main body 1 has a primary bore 2 and a secondary bore 3 integrally arranged in parallel. An air horn 4 is formed at the inlet opening of .3.

A choke valve 5 is rotatably supported on the most upstream side of the primary bore 2, and a primary nozzle 7 is provided inside a small bench lily 6 provided on the downstream side thereof.

Similarly, as best shown in Figure 2, the secondary bore 3
A small bench lily 8 is arranged inside, and a secondary nozzle 9 is provided inside the small bench lily 8.

Further, on the most downstream side of the secondary bore 3, a throttle valve 1 is installed.
0 is rotatably supported by a valve shaft 11, and can be interlocked with a primary throttle valve (not shown) via a lever 12 fixed to the end of the shaft.

A float chamber 51 is formed in the vaporizer body 1 adjacent to both of the pores 2.3 described above (FIG. 2). Liquid fuel is supplied into the float chamber 51 via a float valve body 53 whose opening and closing are controlled by a float 52, so that the fuel oil level in the float chamber 51 is always approximately constant and its storage capacity is always constant. has been done.

A fuel jet 13 is fitted below the liquid level of the float chamber 51, and the fuel drawn in by the intake air passing through the small bench lily 8 is opened into the secondary bore 3 when passing through the air bleed pipe 15. The air introduced from the air passage 17 is mixed in and is ejected from the secondary nozzle 9. Incidentally, the above-mentioned feeding of fuel into the primary bore 2 is performed basically in the same manner as in the secondary bore.

That is, the fuel sucked from the fuel jet 14 by the intake air passing through the small bench lily 6 passes through the air passage 1 opened in the primary bore 2 when passing through the air bleed pipe 16.
The air introduced from the primary nozzle 7 is mixed with the air introduced from the primary nozzle 7.

Further, a valve seat member 22 for receiving the float valve body 53 is provided on the float chamber upper wall 21 of the carburetor main body 1 so as to be inserted into a valve seat attachment hole 23 penetrated in the vertical axis direction. There is. A conduit 24 connected to a fuel tank (not shown) is attached to the side of the upper wall 21 of the float chamber.

Further, in the valve seat member 22, a conduit passage 25 that communicates with the conduit 24 is penetrated in the horizontal axis direction, and a fuel inlet passage 26 that communicates with the float chamber 51 is communicated with the conduit passage 25 in the vertical axis direction. It is penetrated.

Furthermore, a mounting plate 33 is attached to the float chamber side wall 31 of the carburetor body 1 with a seal member 32 interposed therebetween, so that the opening ends 13a, 14a of the plurality of fuel jets 13.14 are attached.
A solenoid valve 35 is provided with a valve body 34 for closing. As clearly shown in FIG. 2, the solenoid valve 35 has a movable rod 36 that is urged toward the closing side of the valve body 34 by the elastic force of a spring, and when energized, the valve body 34 is closed. A solenoid connected to the battery via a switch (not shown) is provided on the opening side to operate the movable rod 36.

As clearly shown in FIGS. 3 and 4, the valve body 34 has a flat valve plate 37 fixed to the tip of the movable rod 36, and has a flat valve plate 37 fixed to the tip of the movable rod 36.
, 14a at the same time by the operation of the movable rod 36 to cut off the fuel supply to the intake passage. The side of the valve plate 37 in the biased position is fixed to the open seal attachment hole 37a. Further, the valve plate attachment portion 36a provided at the tip of the movable rod 36 is formed into a round cross section with a flattened top and bottom surface, and a flattened portion corresponding to the cross section is formed on the attachment portion 36a. It is attached by fitting and caulking the round rod attachment hole 37b.

As clearly shown in FIGS. 5 and 6, the bottom of the float 52 is provided to avoid interference between the valve body 34 of the solenoid valve 35 and the movable rod 36 when the float 52 is lowered. The valve groove 39 connects the valve body 34 and the movable rod 36.
The intake duct side is recessed deeper to correspond to the shape of the intake duct. Further, as shown in FIG.
A guide rail 41 that guides the operation of the valve body 4 and prevents involuntary rotation of the valve body 34 is a protrusion on which the valve body 34 can be placed and moved in correspondence with the valve plate 37. It is formed to protrude by a length of 34 strokes.

Next, the operation of such a fuel control device will be explained.

When the ignition switch is turned on to start the engine, the solenoid 100 of the solenoid valve 35 is energized by a control circuit (not shown), and the movable rod 36 resists the elastic force of the spring and moves away from the fuel jet front end 13a114a. As it moves, the seal member 38 of the valve body 34 follows the movable rod 36 and opens the open ends 13a, 14a. Therefore, the fuel in the float chamber 51 is metered by each fuel jet 13.14, flows into each fuel passage, is ejected from each fuel nozzle 7.9, and becomes an air-fuel mixture with a predetermined air-fuel ratio in the intake passage. Supplied to the engine.

Next, when the ignition switch is turned off to stop the engine, the solenoid 100 is deenergized, and the movable rod 3
6 is returned by the elastic force of the spring, and the sealing member 38 of the valve body 34 is brought into close contact with the fuel jet opening ends 13a, 14.8 at the same time, closing each of the opening ends 13a, 14a at the same time. Therefore, even if heat from various parts of the engine is transferred to the carburetor and boils the fuel in all the floats 51 due to the stoppage of the engine cooling system, the vapor pressure of the boiled fuel will cause the fuel to flow through the fuel passages and into each nozzle. 7.9, undesired discharge is prevented. Furthermore, if the engine speed exceeds a predetermined speed, or if the temperature of the exhaust system catalytic converter reaches a predetermined temperature, a control circuit (not shown) deenergizes the solenoid 100 via a sensor that saves these temperatures.
Similarly to the above, each fuel jet opening end 13a, 14a can be configured to be closed simultaneously. Therefore, high rotation of the engine exceeding a predetermined rotation speed due to high-speed driving or high load is suppressed, it is possible to prevent damage to various parts of the engine due to an abnormal increase in the rotation speed, and it is possible to prevent deterioration of engine performance. Furthermore, it is possible to suppress the temperature rise of the catalytic converter, prevent damage to the catalytic converter due to abnormally high temperatures, and prevent deterioration of the exhaust purification function.

<Effects of the Invention> As described above, according to the present invention, with a simple configuration, it is possible to reliably close the open ends of multiple fuel passages opening into the float chamber, thereby preventing undesired fuel inflow into the intake passage. Therefore, it is possible to obtain a fuel control device for a carburetor that reliably suppresses.

[Brief explanation of drawings]

FIG. 1 is a plan view of a vaporizer to which the present invention is applied. FIG. 2 is a sectional view taken along the line ■-■ in FIG. 1. 3 is an exploded perspective view showing the valve body of the solenoid valve of FIG. 2. FIG. FIG. 4 is a side view showing the valve body of FIG. 2. FIG. 5 is a side view of the float of FIG. 2. FIG. 6 is a sectional view taken along the line Vl-VI in FIG. 5. 1... Carburetor body 2... Primary bore 3.
...Secondary bore 4...Choke bore 5...Choke valve 6.8...Small bench lily 7...Primary nozzle 9...Secondary nozzle 10...Throttle valve 11...Valve stem 12. ...Cam 1
3.14...Fuel jets 13a, 14a...Fuel jet opening end 15.16...Air bleed pipe 17.18...Air passage 22...Valve seat member 23...Valve seat attachment Hole 24... Conduit 25... Conduit path 26...
Fuel inflow path 31... Float chamber side wall 32... Seal member 33... Mounting plate 34... Valve body
35...Solenoid valve 36...Movable lot 3
6a... Valve plate attachment part 37... Valve plate
37b...Rod attachment hole 37a...Seal attachment hole 3
8... Seal member 39... Valve groove 40... Float to intake path side bottom 41... Guide rail 51... Float chamber 52...
...Float 53...Float valve body L...Fuel curved surface patent Applicant: Honda Motor Co., Ltd. Agent: Patent attorney: Yo Oshima - Figure 1, Figure 3, Figure 4, ? Otsu

Claims (4)

[Claims] (1) A fuel control device for a carburetor that uses a solenoid valve to close multiple fuel passages communicating with the float chamber to cut off fuel supply to the intake tract, and is fixed to the tip of a movable rod of the solenoid valve. and a plurality of seal members respectively disposed on the valve plate corresponding to the upstream opening ends of the plurality of fuel passages opening into the float chamber. fuel control device. (2) A valve groove is provided at the bottom of the float to avoid interference between the valve body and the movable rod when the float floating in the float chamber is lowered. Carburetor fuel control device. (3) A fuel control device for a carburetor according to claim 1 or 2, characterized in that a guide rail on which the bottom surface of the valve body is placed and guided is provided at the bottom of the float chamber. . (4) The vaporization according to any one of claims 1 to 3, characterized in that the difference in level between the end faces of the upstream opening ends of the plurality of fuel passages is reduced as much as possible. fuel control device for the vessel.