JPH0444838Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> The present invention uses a solenoid of a solenoid valve for closing a fuel passage communicating with a float chamber and a throttle opening sensor for detecting the throttle opening of a carburetor. This invention relates to a device mounting structure that is mounted on an external surface.

<Prior art> Conventionally, a structure has been known in which a solenoid valve closes the fuel passage communicating with the float chamber to cut off the fuel supply to the intake tract, thereby preventing engine overspeed and protecting the exhaust system catalyzer. In addition, a throttle opening sensor is often used to detect the opening of a throttle valve for purposes such as engine control. Such devices are attached to the outer surface of the vaporizer, but since many devices are generally already attached to the outer surface of the vaporizer, it is preferable to attach these devices to the outer surface of the vaporizer. This can be difficult. As a result, the process of assembling these devices has become complicated, causing an increase in the cost of the vaporizer.

<Problems to be Solved by the Invention> In view of the problems of the prior art, the main purpose of the present invention is to provide a device mounting structure for a vaporizer that is easier to assemble.

<Means for Solving the Problems> According to the present invention, this purpose is achieved by providing a solenoid for a solenoid valve for closing a fuel passage communicating with a float chamber, a throttle opening sensor for detecting a throttle opening, and a throttle opening sensor for detecting a throttle opening. is attached to the outer surface of a carburetor, the device mounting structure characterized in that the solenoid and the throttle opening sensor are attached to the carburetor via a common stay plate. This is achieved by providing structure.

<Function> In this way, by using the same stay plate for the solenoid and the throttle opening sensor, it is possible to reduce the assembly man-hours and the number of parts.

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

Figures 1 to 3 show the entire carburetor to which the device mounting structure based on the present invention is applied, in which a primary bore 2 and a secondary bore 3 are integrally arranged side by side in a carburetor body 1. Both bores 2 and 3
An air horn 4 is formed at the inlet opening.

A chiyoke 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. Further, a small bench lily 8 is provided inside the secondary bore 3, and a secondary nozzle 9 is provided inside the small bench lily 8. On the other hand, on the most downstream side of the primary bore 2, as clearly shown in FIG.
It is rotatably supported by a shaft, and is driven to open and close via a lever 12 fixed to the shaft end. A secondary throttle valve (not shown) is interlocked with the primary throttle valve 10 in a known manner.

A float chamber 51 is formed in the carburetor body 1 adjacent to both of the bores 2 and 3 described above, and liquid fuel introduced from the conduit 24 is controlled to open and close by a float 52. Float valve 53
The fuel storage capacity of the float chamber 51 is kept constant. A fuel jet 13 is fitted horizontally below the liquid level in the float chamber 51, and fuel is supplied toward the air bleed pipe 15. The air bleed pipe 15 is connected to the air jet 1
It communicates with the intake path on the upstream side of the small bench lily 6 through an air bleed passage 17 having an air bleed passage 17, and also communicates with the primary nozzle 7 inside the small bench lily 6.
The fuel sucked from the fuel jet 14 is emulsified by the air from the air bleed passage 17, and is ejected from the primary nozzle 7 toward the intake passage. Note that fuel is fed into the secondary bore 2 basically in the same manner as on the primary side.

A conduit 24 connected to a fuel tank (not shown) is attached to the side of the upper wall 21 of the float chamber. The valve seat member 22 fitted into the valve seat attachment hole 23 penetrated through the float chamber upper wall 21 of the carburetor main body 1 is provided with an internal conduit passage that communicates the conduit 24 with the inside of the float chamber 51. At the same time, a valve seat for the float valve 53 is defined.

Further, a solenoid 35 is attached to the outer surface of the float chamber side wall 31 of the carburetor body 1 via a seal member 32 and a stay plate 33. This solenoid 35 is connected to the valve body 3 via a movable rod 36.
4 to open and close the open end of the fuel jet 13. As best shown in FIG.
A guide rail 41 consisting of a pair of protrusions that guides the valve body 34 is integrally formed on the bottom wall 40 of the float chamber 51 so as to prevent involuntary rotation of the valve body 34 .

Furthermore, a throttle opening sensor 42 is attached to the stay plate 33 for the solenoid 35. An arm 44 fixed to the input shaft of the throttle opening sensor 42 engages with a pin 45 of an arm 43 fixed to the end of the valve shaft 11 of the throttle valve 10 on the side opposite to the lever 12. . The throttle opening sensor 42 is composed of a potentiometer and generates a signal proportional to the rotation angle of its input shaft, that is, the opening of the throttle valve 10. Note that numerals 35a and 46 indicate lead wires of the solenoid 35 and the throttle opening sensor 42, respectively.

In this way, the solenoid 35 and the throttle opening sensor 42 are attached to the carburetor body 1 via the common stay plate 33, which not only reduces the number of manufacturing steps and parts, but also allows these to be assembled into sub-assemblies. This simplifies the manufacturing process of the vaporizer.

Next, the operation of such a carburetor will be explained.

When the ignition switch is turned on to start the engine, the solenoid 35 is energized by a control circuit (not shown), and the movable rod 36 resists the elastic force of the spring built into the solenoid 35 and fires the fuel jet 13.
The valve element 34 follows the movable rod 36 and opens the opening end. Therefore, the fuel in the float chamber 51 is metered by the fuel jet 13 and transferred to the air bleed pipe 15.
The fuel is introduced into the air, is ejected from the fuel nozzle 7, and is supplied to the engine as an air-fuel mixture with a predetermined air-fuel ratio in the intake passage.

Next, when the engine is ignited and the switch is opened to stop the engine, the solenoid 35 is deenergized and the movable rod 36 is moved back by the elastic force of the spring, causing the valve body 34 to close to the open end of the fuel jet 13. will be closed. Therefore, even if heat from various parts of the engine is transferred to the carburetor and boils the fuel in the float chamber 51 due to the engine cooling system being stopped, the vapor pressure of the boiled fuel causes the fuel to flow through the fuel passage and into the nozzle. 7 is avoided.

Furthermore, if the engine speed exceeds the specified speed,
Alternatively, when the temperature of the exhaust system catalyzer reaches a predetermined temperature, a control circuit (not shown) deenergizes the solenoid 35 via a sensor that detects the temperature, and closes the open end of the fuel jet 13 in the same manner as above. can do. Therefore, high rotation of the engine exceeding a predetermined rotation speed due to high-speed running or low load is suppressed, and damage to various parts of the engine due to an abnormal increase in rotation speed can be prevented, and deterioration of engine performance can be prevented. Furthermore, it is possible to suppress the temperature rise of the catalyzer, prevent damage to the catalyzer due to abnormally high temperatures, and prevent deterioration of the exhaust gas purification function.

<Effects of the Invention> As described above, according to the present invention, attachment of external devices to the vaporizer can be facilitated, and the manufacturing process can be simplified and the number of parts can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a vaporizer to which the present invention is applied. FIG. 2 is a side view of the carburetor of FIG. 1.
FIG. 3 is a sectional view taken along the - line in FIG. 2. 1... Carburetor body, 2... Primary bore, 3
...Secondary bore, 4...Air horn, 5...
Chiyoke valve, 6, 8...Small bench lily, 7...Primary nozzle, 9...Secondary nozzle, 10
... Throttle valve, 11 ... Valve shaft, 12 ... Lever, 13 ... Fuel jet, 15 ... Air bleed pipe, 17 ... Air passage, 18 ... Air jet, 22 ... Valve seat member, 23 ... Valve seat attachment hole, 24... Conduit, 25... Conduit path,
26... Fuel inflow path, 32... Seal member, 33
...Stay plate, 34... Valve body, 35... Solenoid valve, 35a... Lead wire, 36... Movable rod, 40... Float chamber bottom wall, 41... Guide rail, 42... Throttle opening sensor ,43,
44... Arm, 45... Pin, 46... Lead wire, 51... Float chamber, 52... Float, 5
3...Float valve.

Claims (1)

[Scope of Claim for Utility Model Registration] A device mounting structure in which a solenoid of a solenoid valve for closing a fuel passage communicating with a float chamber and a throttle opening sensor for detecting the throttle opening are attached to the outer surface of a carburetor. A device mounting structure, characterized in that the solenoid and the throttle opening sensor are mounted to the carburetor via a common stay plate.