JPS58214653A - Compound-type carburetor for turbo engine - Google Patents

Abstract

PURPOSE:To provide the function of a ordinary negative-pressure type compound-type carburetor for a compound-type carburetor installed on the downstream side of the compressor of a turbo engine by permitting opening and closing operation of a secondary throttle valve through utilization of the feeding air stream of the primary air feeding cylinder. CONSTITUTION:During the widely opened operation of a primary throttle valve 15, the pressure in the second pressurization chamber 33 close to an air feeding port part 17 increases larger than the pressure of the first pressurization chambe 32 close to a venturi part, and pushes-up a diaphragm 31 against a spring 36, and the valve plate 35 of a connecting pipe port 34' is opened, and the pressure close to the air feeding port part 17 acts into the pressurization operating chamber 41 of a second throttle valve controlling actuator 40 through a connecting pipe 34, and then a diaphragm 42 is lowered against a spring 45, and a control rod 44 is lowered to open the second throttle valve 24. As the number of revolution of a turbine increases, and the differential pressure between the venturi part of the first air feeding cylinder and the air feeding part 17 increases larger, the control rod 44 is lowered remarkably and the opening of the second throttle valve 24 is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a compound carburetor for a turbo engine, and more particularly to a compound carburetor installed downstream of a turbocharger compressor. When using a compound carburetor in an engine that is not equipped with a turbocharger, a configuration in which the secondary throttle valve is opened and closed by negative pressure in the primary pencilly is mechanically simple and improves the operability of the secondary throttle valve. However, when a compound carburetor is installed downstream of the compressor of a turbo engine, the air supplied to the carburetor is forced supercharging, so the carburetor Since the differential pressure between the air inlet port and the venturi is small, it is possible to control the opening and closing of the secondary throttle valve like in the general engine mentioned above in the same way as in the conventional negative pressure operated compound carburetor. is impossible. The present invention also applies to the compound type carburetor installed downstream of the compressor of a turbo engine, by using the air flow of the primary feed cylinder to open and close the secondary throttle valve, thereby improving the general negative pressure compound type carburetor as described above. The purpose of the present invention is to provide a compound type vaporizer that can have a function similar to that of a vaporizer.
An air supply pulp is provided that opens and closes depending on the pressure difference between the air supply port of the secondary cylinder and a part of the venturi, and the secondary throttle valve control actuator is operated by the amount of air supplied from the pulp, and the secondary throttle valve is controlled by the actuator. It controls the opening and closing of the

Next, the present invention will be explained with reference to embodiment drawings.

FIG. 1 shows a turbo-type compound carburetor according to the present invention.
In this figure, a compound carburetor 4 is installed downstream of a compressor 3 of a turbocharger 2 installed in an engine 1.

5 is leak and pulp, which will be explained later, and 6 is 2, which will be explained later.
Next is the throttle valve control actuator.

7 is an air cleaner, 8 is a turbine, and 9 is a muffler.

FIG. 2 shows an enlarged sectional view of one embodiment of the compound type vaporizer according to the present invention. Venturi passages 13 and 23 are led from a venturi portion 12 of the primary feed cylinder 11 and a venturi portion 22 of the secondary feed cylinder 21, respectively.

The two air passages 13 and 23 are made into one air passage 14 and led out of the carburetor. 15 is the primary throttle valve, 16
2 is a main fuel nozzle connected to the fuel chamber 10, 24 is a secondary throttle valve, and 25 is a secondary fuel nozzle. Then, an air supply pulp 30 is provided attached to the vaporizer or separately at a suitable location. The air supply pulp 30 is connected to a first pressurizing chamber 32 and a second pressurizing chamber 33 by a pressure-operated diaphragm 31.
The first pressurizing chamber 32 is connected to the air passage 14 from the venturi part 12, and the second pressurizing chamber 33 is connected to the air passage 14 from the venturi part 12 of the carburetor. Ventilation pipe 1
8. Therefore, the pressure of the venturi portion 12 acts on the first pressurizing chamber 32, and the pressure of the primary air supply port 17 acts on the pressurizing chamber 33. In addition, the second pressurizing chamber 33
'T2 of the carburetor: the pressurized operating chamber 41 of the secondary throttle valve control actuator 4o that controls the opening and closing of the secondary throttle valve 24;
A connecting pipe 34 leading to is attached.

A valve plate 35 is attached to the diaphragm 31 for opening and closing the pipe port 34' of the connecting pipe 34, and the valve plate 35 is connected to the first pressurizing chamber 3.
2, which normally closes the connecting pipe port 34'. The connecting pipe 34 is provided with an orifice 37 on its way to the secondary throttle valve control actuator 40 and opens to the atmosphere via an orifice 38.

The secondary throttle valve control actuator 4゜3- has a pressure-operated diaphragm 42 in which the pressurized chamber 41 and the atmospheric chamber 43 are formed, and the diaphragm 42 controls the opening and closing of the secondary throttle valve 25. Con).

- A control rod 44 is connected, and the atmospheric chamber 43 is provided with a coil spring 45 for pushing up the diaphragm 42, which normally pushes up the control rod 44 to close the secondary throttle valve 24.

With the above configuration, when the primary throttle valve 15 is operated wide open as shown in FIG. Even though the pressure in the first pressurizing chamber 32 is higher than the pressure in the second pressurizing chamber from the air supply port 17, the diaphragm 3
1 against the spring 36, and press the valve plate 3 of the connecting pipe port 34'.
5 is opened, the pressure from the air supply port 17 is increased from the connecting pipe 34 to 9.
It acts on the pressurized chamber 41 of the secondary throttle valve control actuator 40 to lower the diaphragm 42 against the spring 45, pushing down the control rod 44 and opening the secondary throttle valve 24. Therefore, as the rotational speed of the turbine increases (as the engine rotational speed increases) and the differential pressure between the primary cylinder part and the air supply section 17 increases, the control rod 44 increases. Press down greatly to open the secondary throttle valve 24.

Orifices 37 and 3 of the connecting pipe 34 connecting the air supply pulp 30 and the secondary throttle valve control actuator 40
Reference numeral 8 serves to prevent sudden opening of the secondary throttle valve 24 by slowing down the sudden operation of the control φ actuator 4°.

As described above, according to the compound type carburetor according to the present invention, even when installed downstream of the compressor of a turbo engine, a part of the venturi and the air inlet when the primary throttle valve of the primary feed cylinder is wide open Since the secondary throttle valve is opened and closed by the pressure at the air supply port using the differential pressure between the This enables smooth operation of the throttle valve and high-performance operation of the secondary feed cylinder according to the rotation of the upper engine.

[Brief explanation of the drawing]

FIG. 1 shows a turbo-type compound carburetor according to the present invention.
FIG. 2 is an enlarged sectional view of a compound type carburetor according to an embodiment of the present invention. 11---Primary feed cylinder, 1.2---Part of primary feed cylinder venturi, 15---Primary throttle valve. 17---Primary supply cylinder air supply port. 22---Part of the secondary feed cylinder venturi. 24---Secondary throttle valve, 30---First air supply valve. 32--1 first pressurizing chamber, 33--1 second pressurizing chamber. 4.0---Secondary throttle valve control actuator. 41-m-pressurized working chamber. Applicant Mikuni Kogyo Co., Ltd. 7- Figure 1

Claims (1)

[Claims] An air-supplying pulp comprising a first pressurizing chamber communicating with a portion of a venturi and a second pressurizing chamber communicating with an air inlet port of a primary cylinder; and the second pressurizing chamber of the air-supplying pulp. A pressurized operating chamber is provided in communication with the vent IJ, which opens and closes the secondary throttle valve in proportion to the pressure difference between the part of the vent IJ and the air inlet of the primary cylinder when the pressure difference exceeds a certain pressure. A compound type carburetor for a turbo engine, characterized by comprising a secondary throttle valve control actuator for operation.