JPH04183963A - Power device for carburetor - Google Patents

Abstract

PURPOSE:To enable the aspiration of additional fuel of a sufficient flow quantity in a high-load operation region of an supercharger-equipped engine by constituting the device in such a way that an additional fuel measured by a power valve is aspirated into a venturi through a power nozzle other than a main nozzle. CONSTITUTION:When a power valve 11 is opened in a high-load operation region in which the negative pressure in an intake pipe is low, an additional fuel measured by a valve port 14 is aspirated into the intake passage 2 through an additional fuel passage 26 due to the venturi negative pressure acting on a power nozzle 25. When the engine enters a high-load high-speed operation and the negative pressure in the intake pipe becomes relatively high, a diaphragm 21 displaces towards a negative- pressure chamber 22 to decrease the opening of the power valve 11, however, since the venturi negative pressure is also increased, the amount of aspiration to the intake passage 2 is not decreased. On the other hand, at the time of high-load low-speed operation, since the negative pressure in the intake pipe is extremely low, the opening of the power valve 11 is increased, however, since the venturi negative pressure is very low, the amount of aspiration to the intake passage 2 is not increased. Thus, the amount of additional fuel can be optimized, and fuel economy can be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a power device provided in a carburetor for supplying a highly concentrated air-fuel mixture in a high-load operating range of an engine. A carburetor equipped with such a power device is used to supply fuel to a supercharged engine.

[Prior Art] As is well known, the power device of a carburetor opens the power valve by utilizing the high opening degree of the throttle valve or the low negative pressure in the suction pipe in the high-load operating range of the engine. This system supplies a highly concentrated air-fuel mixture by introducing the fuel from the float chamber into the main well of the main fuel passage, effectively utilizing the intake air for combustion in the extremely short combustion time associated with the high speed rotation of the engine. This is a system in which additional twists 4-1 are combined to obtain output.

However, in the case of a supercharged engine, an extremely high concentration of air-fuel mixture is required in order to lower the combustion temperature in the high-load operating range, so this is indispensable for high-load operation of engines without a supercharger. The additional fuel flow bI6 is insufficient in a power device designed to do so. As a countermeasure, it is possible to increase the additional fuel flow introduced from the float chamber to the main well by increasing the diameter of the power valve (1-1). Since there is a limit to the fuel flow sucked out from the nozzle, it is not possible to supply the required high concentration mixture.

[Problem to be Solved by the Invention] The problem to be solved by the present invention is that in the conventional carburetor power device, it is difficult to generate a high-concentration air-fuel mixture sufficient to lower the combustion temperature in the high-load operating range of a supercharged engine. The point is that it cannot be supplied.

Accordingly, an object of the present invention is to provide a power device that can supply an extremely high concentration air-fuel mixture to an engine in a high load operating range.

Means for Solving 1 Problem] In order to solve the above problem, the present invention provides a means for connecting an additional fuel passage communicated with the outlet of the power valve to a power nozzle opened in a venturi separately from the main nozzle. anchored.

The power valve is a negative pressure operated type that opens and closes due to negative pressure in the suction pipe, and the power nozzle is installed at the narrowest part of the venturi.
It is better to let it be I.

[Function] When the valve p opens in the high-load operating range of the engine, additional fuel is sucked out from the power nozzle to the intake passage through the additional fuel passage by the venturi negative pressure acting on the power nozzle. That is, additional fuel can be supplied without being restricted by conditions such as the diameter of the king nozzle.

[Example] The present invention will be described in detail with reference to the drawings.

The drawing shows an example in which the power device of the present invention is applied to a carburetor in which the intake passage is oriented horizontally and the float chamber is arranged below, and has an intake passage 2 provided with a venturi 3 and a throttle valve 4. A gamma chamber 5 is fixed on the side of the vaporizer main body 1, and a 1-liter-shaped part 6 hanging from the vaporizer main body 1 in the center of the float chamber 5 has a main jet 7, a main well 8, and an emulsion flowing from bottom to top. A pipe 9 and a king nozzle 10 are arranged side by side, and the fuel 1 in the float chamber 5 is metered by the nitrogen jet 7, enters the main well 8, is mixed with bleed air in the emulsion pipe 9, and is sent from the main nozzle 10 to the top of the venturi 3. It is sucked out into the narrow part.

A power valve 11 is installed at the bottom of the float chamber 5. This power valve 11 has a port 13 that communicates with the inside of the float chamber 5 and an outlet 15 that communicates with the outlet chamber 20 via a valve port 14, and a valve body 12 that is fixed to the float chamber 5 by screw connection. It consists of a conical valve body 18 inserted into a valve chamber 16 and actuated by a closing spring 17, and a valve rod 19 integrated with the valve body 18 projects from an outlet 015 to an outlet 1 chamber 20.

The part of the outlet chamber 20 facing the power valve 1 is formed by a diaphragm 21, and the part opposite to the outlet chamber 20 is formed by an actuating spring 2.
3 is inserted into a negative pressure chamber 22, and communicates with the intake path 2 downstream of the throttle valve 4 through a negative pressure passage 24. When the suction pipe negative pressure generated downstream of the throttle valve 4 is high, the diaphragm 21 is displaced toward the negative pressure chamber 22 and the valve body 19
However, when the suction negative pressure becomes low, it is displaced toward the outlet chamber 20 by the spring force of the operating spring 23, pushing the valve stem 19 and opening the power valve 11. This operation is the same as a conventional negative pressure operated power device.

The exit chamber 22 protrudes into the narrowest part of the venturi 3 and opens II.
The fuel nozzle 25 is connected to the fuel nozzle 25 by an additional fuel passage 26.

When the power valve 11 opens as described above in the negative pressure in the suction pipe is low in the ☆; is sucked out from the power nozzle 25 to the intake passage 2. In this case, during high load, '+'r, and high speed operation, the suction spear negative pressure becomes relatively high, and the diaphragm 21 is displaced toward the negative pressure chamber 22. Although the opening degree of the power valve 11 is reduced, the amount of suction into the intake passage 2 is not reduced because the venturi negative pressure also increases.

Furthermore, during high-load, low-speed operation, the suction pipe negative pressure is extremely low, so the diaphragm 21 is largely displaced toward the outlet chamber 20, increasing the opening degree of the power valve 11. However, since the venturi negative pressure is also extremely low, the suction pipe negative pressure is extremely low. Do not increase the amount of suction to.

Incidentally, by appropriately setting the maximum effective area of the valve I14 and the inner diameter of the power nozzle 25, it is also possible to reduce the amount of additional fuel required during high-load, low-speed operation to improve fuel economy.

In this embodiment, the power valve 11 is operated under negative pressure to adjust the additional fuel flow rate in relation to the venturi negative pressure, but a mechanically operated type linked to the throttle valve 4 may be used. In addition, the present invention can of course be applied to a carburetor in which the intake passage 2 is directed downward. However, it goes without saying that it is actually formed inside these.

[Effects of the Invention] According to the present invention, the additional fuel metered by the power valve is sucked out to the venturi from the power nozzle that is different from the main nozzle, and the additional fuel is sucked out to the venturi from the power nozzle that is different from the main nozzle. Additional fuel flow can be drawn off to create a very rich mixture and reduce combustion temperatures.

[Brief explanation of the drawing]

The drawings are longitudinal sectional views showing embodiments of the present invention. 2 Intake path, 3 Venturi, 5 Float chamber, 11...
Power valve, 13. Population, 15.. Outlet, 18.. Valve body, 25.. Power nozzle, 26.. Additional fuel passage, -7-\

Claims (1)

[Scope of Claims] 1. A power device for a carburetor, characterized in that an additional fuel passage communicating with the outlet of the power valve is connected to a power nozzle opened in a vent lily separately from the main nozzle. 2. The power device for a carburetor according to claim 1, wherein the power valve is operated under negative pressure to open and close by negative pressure in the suction pipe, and the power nozzle opens at the narrowest part of the bench lily.