RU84920U1 - CARBURETTOR WITH SEQUENT OPENING OF FUEL AIR CAMERAS - Google Patents

Abstract

1. A carburetor with sequential opening of the fuel air chambers, comprising: a float chamber configured to dispense fuel into the fuel air duct, a fuel air duct comprising a primary and secondary fuel air chambers, each of which includes a diffuser, a throttle valve with a drive and a sprayer, mounted on two mounting ribs in the cavity of the diffuser, made in the form of a tube having a neck, a cylindrical part and a conical part, and communicates with the float chamber through a channel provided in one of these ribs, a lid equipped with an air damper configured to allow air to pass into the air-fuel duct, and an idle system in communication with the float chamber and allowing air-fuel mixture to bypass the throttle valves, characterized in that in one of of said mounting ribs of the sprayer, a correction channel is made providing communication between the sprayer channel and the upper part of the diffuser cavity, while the ratio of the minimum diameter Sprayer neck cavity to the diameter of its cylindrical part of the cavity satisfies the condition: 0.7 <D1 / D2 <0.74,! where D1 is the minimum diameter of the cavity of the nozzle neck, D2 is the diameter of the cavity of the cylindrical part of the spray,! and the ratio of the diameters of the correction channel and the spray channel satisfies the condition:! 0.17 <d1 / d2 <0.19,! where d1 is the diameter of the correction channel, d2 is the diameter of the spray channel. ! 2. The carburetor according to claim 1, characterized in that the plane of symmetry of the mounting ribs is placed at an angle, the imaginary peak of which is located in

Description

Technical field

The invention relates to a carburetor for an internal combustion engine, i.e. a device for dispensing liquid fuel in an air stream with the formation of a combustible mixture and for the controlled supply of this mixture to the engine cylinders. More specifically, the utility model relates to a carburetor with sequential opening of air-fuel chambers.

State of the art

It is well known that the efficiency of an engine depends, inter alia, on how quickly and completely the fuel burns in its cylinders. In this regard, the task of preparing a fuel-air mixture for combustion by a carburetor is very important. The specified preparation consists in the adjustable direction of the fuel jet into a fast-moving air stream, which breaks this jet into small droplets, thus forming a fuel-air mixture.

Based on the foregoing, the main requirements for a carburetor are:

- the formation of a high-quality homogeneous air-fuel mixture with a high degree of atomization of fuel;

- ensuring the optimal change in the composition of the mixture depending on the operating mode of the engine (start, idle mode, maximum power mode).

Currently, the most common carburetors on the Russian market are K-151 series carburetors with sequential opening of fuel-air chambers. These carburetors have been used successfully for more than ten years to complete the engines of most domestic cars, including GAZ, UAZ, IZH and Moskvich cars.

A typical K-151 carburetor contains:

- float chamber, made with the possibility of metered delivery of fuel into the fuel-air tract,

- the air-fuel tract, including the primary and secondary air-fuel chambers, each of which contains a diffuser, a throttle with a drive and a spray, which is mounted on two mounting ribs in the cavity of the diffuser, is made in the form of a tube having a neck, a cylindrical part and a conical part, and is communicated with a float chamber through a channel provided in one of these ribs,

- a cover equipped with an air damper configured to allow air to pass into the air-fuel tract,

- and an idle system that communicates with the float chamber and ensures the passage of the air-fuel mixture bypassing the throttle valves.

Such carburetors are described in detail in the book of A. S. Tyufyakov “Carburetors K-151” (Publishing House “Behind the Wheel”, 2005). They are characterized by relatively low cost and quite acceptable quality. However, unfortunately, the elements of the air-fuel path of the K-151 series carburetors, due to their not quite optimal volume and geometry parameters, provide insufficiently effective atomization of the air-fuel mixture at low air flow rates, i.e. at small and medium engine powers. More specifically, during the operation of these carburetors under partial loads, stagnation regions may form in the spray cavity and breaks in the flow of the air-fuel mixture may occur. Spurious pulsations can also occur in the spray channel. All this negatively affects the emulsification of fuel, the quality of mixture formation and distribution of fuel.

Thus, the objective of this utility model is to create a carburetor with sequential opening of the air-fuel chambers, devoid of the disadvantages of similar devices of the prior art.

More specifically, this utility model aims to create a carburetor in which:

- provides an improved distribution of pressures and speeds for better atomization of fuel in the air stream (increasing the efficiency of mixture formation);

- there are no stagnation areas of the air-fuel mixture, which minimizes kinematic losses (increasing the efficiency of mixture formation);

- provides the adjustment of the mass flow of fuel in the channel of the atomizer depending on the operating mode of the carburetor (improving the quality of emulsification);

- reduced the likelihood of spurious pressure pulsations in the spray channel during transient conditions (more uniform distribution of fuel across the cylinders).

An additional task of the utility model is to create a carburetor, in which:

- the network of chambers and channels has been simplified and hydraulic losses in the air-fuel tract have been minimized;

- reduced the cost of the carburetor;

- Provides ease of maintenance and repair.

Utility Model Essence

The problem is solved by creating a carburetor with a sequential opening of the air-fuel chambers, including:

a float chamber configured to dispense dosed fuel into the air-fuel tract,

a fuel-air duct comprising a primary and secondary fuel-air chambers, each of which includes a diffuser, a throttle with a drive and a spray, which is mounted on two mounting ribs in the cavity of the diffuser, made in the form of a tube having a neck, a cylindrical section and a conical section, and communicates with the float chamber through a channel provided in one of these ribs,

a cover equipped with an air damper configured to allow air to pass into the fuel-air duct, and an idle system that communicates with the float chamber and allows the air-fuel mixture to pass bypass the throttle valves.

The proposed carburetor is characterized in that in one of the mounting ribs of the spray gun there is a correction channel that provides communication between the spray gun channel and the upper part of the diffuser cavity, while the ratio of the minimum diameter of the spray neck cavity to the diameter of the cavity of its cylindrical part satisfies the condition:

0.7 <D1 / D2 <0.74,

where D1 is the minimum diameter of the cavity of the nozzle of the spray, D2 is the diameter of the cavity of the cylindrical part of the spray,

and the ratio of the diameters of the correction channel and the spray channel satisfies the condition:

0.17 <d1 / d2 <0.19,

where d1 is the diameter of the correction channel, d2 is the diameter of the spray channel.

When choosing the ratio D1 / D2 satisfying the condition 0.7 <D1 / D2 <0.74, an improved distribution of pressures and speeds is provided for better spraying of fuel in the air stream. There are no stagnation regions of the air-fuel mixture, and the flow turbulence is such that the mixture formed in the spray zone passes through the mixing zone with minimal kinematic losses.

Due to the presence of a correction channel in one of the mounting ribs of the spray gun providing communication between the spray channel and the upper part of the diffuser cavity, the probability of pressure pulsations in the flow is eliminated, which qualitatively affects the operation of the carburetor. Moreover, when choosing the ratio d1 / d2 satisfying the condition 0.17 <d1 / d2 <0.19, an effective adjustment of the mass fuel consumption in the spray channel is provided depending on the operating mode of the carburetor. And at the maximum opening of both throttle valves (i.e. in maximum power mode), this ratio ensures uniform distribution of fuel in the chambers.

According to a preferred embodiment of the utility model, the symmetry planes of the mounting ribs are placed at an angle whose imaginary apex is located in the float chamber. This design of the carburetor allows you to simplify the network of chambers and channels and to avoid the appearance of additional hydraulic losses in the fuel-air ducts. In this regard, we note that each bend of the channel is a hydraulic resistance, i.e. a place where accumulation of dirt in the fuel is possible. In addition, a simple network of fuel channels inside the housing allows you to reduce the cost of the site and facilitates its subsequent maintenance and repair.

Brief Description of the Drawings

Below, the utility model is described in more detail using an example of a preferred embodiment disclosed with reference to the accompanying drawings, in which:

figure 1 depicts a diagram of the proposed carburetor;

figure 2 depicts a spray in cross section;

figure 3 depicts the proposed carburetor from above.

Description of the preferred embodiment of the utility model

The proposed carburetor 1 is illustrated in FIGS. 1 and 3. The main functional parts of the carburetor 1 are a float chamber 2, an air-fuel duct 3, an idle system 12, 13, 14 and a cover (not shown).

The float chamber 2 is designed for the dosed delivery of liquid fuel into the air-fuel tract 3, in which the formation of the air-fuel mixture occurs during the main engine operation mode.

The fuel-air tract 3 contains a primary and secondary air-fuel chambers 4, 5, each of which includes a diffuser 6, a throttle valve 7 with a drive and a spray gun 8 (shown in more detail in figure 2), made in the form of a tube having a neck 16, cylindrical section 17 and the conical section 18. The spray 8 is mounted on two mounting ribs 9 in the cavity of the diffuser 6 and communicates with the float chamber 2 through the channel 10 provided in one of these ribs 9.

The lid covers the carburetor from above. It is equipped with fastening elements of the air filter, as well as an air damper 11, made with the possibility of passing air into the fuel-air path 3 of the carburetor.

The idle system 12, 13, 14 communicates with the float chamber 2 and ensures the passage of the air-fuel mixture bypassing the throttle valves 7 in the engine idle mode. It essentially consists of a bypass channel 12, a regulating element 13 and an emulsion tube 14. In this regard, it should be noted that the improvements provided by the proposed carburetor relate to the main engine operation mode, and not to the idle mode, and therefore are not related to idle system design. Given this circumstance, to disclose the idle system in this description in more detail there is no need. You can only indicate that the idle system has a standard design, well known to specialists in this field of technology.

The proposed carburetor 1 is characterized in that in one of the mounting ribs 9 of the atomizer 8 there is a correction channel 15 that provides communication between the atomizer channel 10 and the upper part of the diffuser cavity 6, while the ratio of the minimum diameter of the nozzle neck 16 to the diameter of the cavity of its cylindrical part 17 satisfies the condition:

0.7 <D1 / D2 <0.74,

where D1 is the minimum diameter of the cavity of the neck 16 of the spray gun, D2 is the diameter of the cavity of the cylindrical part 17 of the spray gun,

and the ratio of the diameters of the correction channel 15 and the channel 10 of the atomizer satisfies the condition:

0.17 <d1 / d2 <0.19, where d1 is the diameter of the correction channel 15, d2 is the diameter of the channel 10 of the atomizer.

According to a preferred embodiment of the utility model, the symmetry planes of the mounting ribs 9 are placed at an angle whose imaginary peak is located in the float chamber 2.

The claimed carburetor 1 operates as follows. In idle mode, the formation of the air-fuel mixture proceeds similarly to what happens in the well-known carburetor of the 151K series. Without going into too much detail, we indicate that in this mode the throttle valves 7 are closed and the vacuum acting in the inlet pipe of the cylinders of the internal combustion engine forces the fuel is sucked up from the float chamber 2 not into the atomizer 8, but into the emulsion tube 14, where it is emulsified by air introduced into the carburetor by the air damper 11. Further, the formed air-fuel system ect enters the bypass duct 12 from the emulsion in the tube 14 cylinder internal combustion engine, wherein the parameters are regulated by the mixture regulating element 14.

When you press the gas pedal in the car, the carburetor 1 goes into the main mode of operation. At this time, the throttle valves 7 open, and air begins to flow into the diffusers 6 of the air-fuel chambers 4, 5 through the air damper 11. It should be noted that in a carburetor with sequential opening of the air-fuel chambers, the damper actuator is designed in such a way that it provides not simultaneous, but sequential opening of the damper. First, the shutter 7 of the primary chamber 4 is opened, causing air to enter the cavity of the first diffuser 6, and then, with some delay, the shutter 7 of the secondary chamber 5 opens, after which air begins to flow into the cavity of the diffuser 6 of the secondary chamber 5.

The vacuum acting in the fuel-air chambers 4, 5 forces the fuel to be sucked from the float chamber 2 into the atomizer 8, where it is broken up by a stream of air into small droplets and, mixed with air, then flows into the cylinders of the internal combustion engine.

The presence in one of the mounting ribs 9 of the correction channel 15, which provides communication between the channel 10 of the atomizer and the upper part of the cavity of the diffuser 6, reduces the likelihood of spurious pressure pulsations in the channel of the atomizer during transient conditions (more uniform distribution of fuel across the cylinders).

Moreover, in the course of numerous studies and field tests, it was found that due to the implementation of the atomizer 8 having the above values of the ratios D1 / D2 and d1 / d2, the carburetor acquires a number of advantages not characteristic of the known K151 carburetors, namely:

- provides an improved distribution of pressures and speeds for better atomization of fuel in the air stream (increasing the efficiency of mixture formation);

- there are no stagnation areas of the air-fuel mixture, which minimizes kinematic losses (increasing the efficiency of mixture formation);

- provides the adjustment of the mass fuel consumption in the channel of the atomizer depending on the operating mode of the carburetor (improving the quality of emulsification).

In addition, according to a preferred embodiment of the utility model, the symmetry planes of the mounting ribs (9) of the spray gun are placed at an angle whose imaginary peak is located in the float chamber (2). This design allows you to:

- to simplify the network of chambers and channels and minimize hydraulic losses in the air-fuel tracts;

- reduce the cost of the carburetor;

- to provide ease of maintenance and repair of the carburetor. Thus, the carburetor disclosed in this application is free from the disadvantages of the prior art. This means that the proposed technical solution can successfully solve the tasks set in the application.

In conclusion, the applicant considers it appropriate to inform that in this description only some preferred options of the claimed fuel filter are disclosed, which should not be construed as limiting the patent claims of a utility model. Those skilled in the art will understand that various changes and additions may be made to the embodiment described and shown in the drawings, without departing from the legal protection of this utility model established by the attached formula.

LIST OF POSITION NUMBERS

1 - Carburetor

2 - Float chamber

3 - Fuel-air tract

4 - Primary air-fuel chamber

5 - Secondary fuel air chamber

6 - Diffuser

7 - Throttle

8 - Sprayer

9 - Fixing ribs

10 - Spray Channel

11 - Air damper

(12, 13, 14) - Idle System

12 - Bypass channel

13 - Regulating element

14 - Emulsion tube

15 - Correction channel

16 - Spray neck

17 - The cylindrical part of the sprayer

18 - Cone of the sprayer

Claims (2)

1. A carburetor with sequential opening of the fuel air chambers, comprising: a float chamber configured to dispense fuel into the fuel air duct, a fuel air duct comprising a primary and secondary fuel air chambers, each of which includes a diffuser, a throttle valve with a drive and a sprayer, mounted on two mounting ribs in the cavity of the diffuser, made in the form of a tube having a neck, a cylindrical part and a conical part, and communicates with the float chamber through a channel provided in one of these ribs, a lid equipped with an air damper configured to allow air to pass into the air-fuel duct, and an idle system in communication with the float chamber and allowing air-fuel mixture to bypass the throttle valves, characterized in that in one of of said mounting ribs of the sprayer, a correction channel is made providing communication between the sprayer channel and the upper part of the diffuser cavity, while the ratio of the minimum diameter Sprayer neck cavity to the diameter of its cylindrical cavity portion satisfies the following condition: 0.7 <D1 / D2 <0.74, where D1 is the minimum diameter of the cavity of the nozzle of the spray, D2 is the diameter of the cavity of the cylindrical part of the spray, and the ratio of the diameters of the correction channel and the spray channel satisfies the condition: 0.17 <d1 / d2 <0.19, where d1 is the diameter of the correction channel, d2 is the diameter of the spray channel. 2. The carburetor according to claim 1, characterized in that the plane of symmetry of the mounting ribs is placed at an angle, the imaginary peak of which is located in the float chamber.