Description of the carburetor and some elements of the power system

Description of the carburetor and some elements of the power system
Carburettor engines 4A-5A-P and P - with dual-chamber sequence ¬ nym discovery of primary and secondary chambers. When the engine is at low and medium loads and dosage in ¬ giving fuel and mixing it with air, made solely ¬ Indeed the primary (main) camera carburetor. When working at high load or high speed dispensing and supply top ¬ Lebanon, as well as its mixture with air, carried by both chambers. The operating principle of thecarburetor is based on the use of van ¬ vacuum in the intake tract for the fuel and mixing it with air. ¬ constructive but carburetor includes: differential ¬ fuzor that actually "measures" the air flow, the float chamber, which is a battery of fuel dispenser, Th ¬ res that fuel comes in air ¬ stuffy tract, and throttle position from which depends on air flow and, consequently, the amount of vacuum in the diffuser. The vacuum in the intake tract creates a pumping action of the engine when the intake stroke, air or a mixture followed by ne-remeschayuschimsya piston. With passage of air through Denia ¬ ce ¬ narrowing value (diffuser), his speed increased ¬ ourselves to, and the pressure decreases, which leads to under ¬ flow of fuel through the nozzle and spray into the air tract. Air flow, and hence ¬ but depression in the cone depends on engine speed and position of the throttle ¬. The fuel coming through the spray distribution pylivaetsya air flow, partially evaporated, and the fuel-air mixture enters the intake manifold. Carburetor float chamber, not only temporarily accumulates the fuel supplied to the fuel pump, but also acts as a stabilizer to the fuel metering Op-ganami that is needed to properly manage the process of ¬ toplivopoda Chi. In the carburetor float chamber float and a needle is placed clusters ¬ pan. For damping vibrations of float needle valve has a spring and ball bearing inside.
Air path of the primary chamber ¬ Ry made by the traditional two-diffuser scheme and includes: air damper 5, a small sdvoen ¬ ny diffuser with sprayer, large diffuser and the throttle for slonku ¬ 16. The output section 1 (small) of the diffuser is located in a narrow ¬ Coy of the 2nd (large) cone, ie in the zone of increased rarefaction ¬ Nij. This pattern of air path:
• increases in depression Spray ¬ telya;
• creates a flow and structure of the mixing ¬ B, preventing the deposition of fuel
on the walls of the air duct;
• distributes the air flow increases fuel consumption by increasing the flow of air through the annular gap between small and large cones that way, there exists a constant composition of the combustible mixture in a wide range of divergence ¬ Dov air.
Main metering system
Scheme the carburetor engines 4A-5A-P and P. 1 - plunger (piston) pump ac ¬ Satisfactory, 2 - discharge valve (gravity), the US-koritelnogo pump, 3 - solenoid cutoff toplivopoda Chi secondary chamber carburetor (only for models with 3-component catalyst ¬ nym for Germany) 4 - spray (combined with a small cone), the secondary chamber, 5 - air damper, b - ¬ pylitel races (combined with a small cone), the primary chamber,
7 - solenoid valve, fuel cut-off of the primary chamber,
8 - main jet idling (primary camera), 9 - piston air economizer, 10 - float 11 - needle valve fuel, 12 - valve economizer, 13 - main fuel zhik ¬ ler of the primary chamber, 14 - a variant of the adjustment screw mixture of normal idle speed (model for Europe and Singapore) 15 - screw adjustment of the mixture of the normal idle speed (screw the "quality"), 16-throttle primary chamber, 17-valve throttle ¬ Nye the secondary chamber, 18 - actuator (diaphragm ME ¬ mechanism of the drive) throttle the secondary chamber, 19 - ¬ ny jet fuels in the transitional system (secondary camera), 20 - ¬ corrector with a mixture composition of idling when the engine warms up (primarily for systems with order intake of warm air), 21 - main fuel the second jet ¬ ondary chamber, 22 - an additional (secondary) accelerator pump.
Fuel delivery system with a carburetor
primary chamber (SDS-1) includes a main jet 13, main air jet and sputtering subgroup 6. In the same fuel path goes through the fuel valve 12 is pneumatically controlled economic mayzera 9. SDS-1 gives the basic of quantity of fuel in most pa-bochih mode engine which depression in the venturi, creating, my air flow is sufficient to lift fuel to the level of the mouth of the gun and received it in by air tract. Adjusting this system provides an economic theme ¬ ¬ by becoming a mixture of what is needed in a broad range of high-speed com ¬ and ¬ nagruzoch GOVERNMENTAL regimes. However, to obtain maximum power, as well as to the satisfactory performance of engines-la in the transition process (for insta ¬ chestnut modes during acceleration or engine during fast throttle) uses auxiliary systems: the economizer system and accelerator pump ¬ Nogo.
Primary camera carburetor serves primarily the work of motion gatelya in small and medium loads. Due to the small bore-holes are provided with air duct high velocity air, good fuel atomization and high honors ka ¬ mixing, which, along with economical composition of the mixture leads to an economical engines work ¬ A in these conditions. However, the regime ¬ max full load (especially at high speeds) the small orifices of the primary chamber can not provide the necessary filling of the engine, and depleted of adjustment - horsepower (enriched-tion) of the mixture required to obtain the maximum cardinality of the engine stnyh. The idling of the primary ¬ Chamber as included in the main pre-ziruyuschuyu system after the main jet is plivnogo-13 and includes a cross-os: a main jet 10 idle, idle air jet 8, the solenoid valve is switched off the fuel supply of ¬ 9, screw regulation
renormalization of the mixture at idle 15 and two output holes on to ¬ torym fuel mixture enters the chamber ¬ relatively near the edge of the carburetor throttle body. The system of the holo ¬ stack delivers fuel to the main mode for small loads, when the primary throttle steps ka ¬ opened a slight angle and a vacuum in the diffuser not enough to fuel revenue from GDS-1, a vacuum in the intake labor ¬ boprovode contrast, very large. Air jet idling reduces the vacuum in the well system, we ¬ idle up to the required level.
The second (upper) outlet system idling engine provides a smooth transition from the regime of small to medium loads. If you open the throttle vanii ¬ it ¬ priest gives in the high vacuum area, which compensates for the reduction of depression in the channel system idle due to the reduction zadrosselnogo dilution. This leads to a continuous age ¬ taniyu fuel as an open ¬ ment throttle, thereby preventing possible depletion ¬ tion mixture prior to inclusion of SDS-1. The idling is working with ¬ tion with SDS-1 in a wide range of loads, with significant influence on the characteristic ¬ tion carburetor. However, making it the number of senior Lib ¬ decreases as the load increases.
Electromagnetic valve 7 primary chamber carburetor off the fuel supply through the idling, closing a fuel path after you plug ¬ prisoners. These prevent ¬ schaetsya engine operation at low speeds when ignition is turned off by the ignition of a mixture of hot elements of the combustion chamber (so-called surface ignition or "dizeling"). Air tract secondary ka ¬ action is also made by dvuhdiffu-Zorn scheme and includes: a small cone with a spray 4 large diffuser and a secondary throttle valve 17. Last controlled by a diaphragm mechanism 18, depending on the ratio of time ¬ rarefaction in large diffusers per ¬ tion of primary and secondary chambers carburetor. Almost secondary throttle ¬ ondary chamber starts to open at high speeds, when the primary chamber orifices can not provide the necessary complement to the ¬ motor. Opening Drosia ¬ selnoy valve 17 only after the engine warms up (the opening of the choke), and after covering from ¬ 16 per throttle ¬ tion of primary chamber at a certain angle. Air tract secondary chamber has large orifices (larger diameter of the diffuser and large shy diameter mixing chamber), compared with the bore of the same elements of the primary chamber.
The solenoid valve 3 of secondary chamber carburetor switch-off denotes the supply of fuel through the passage ¬ nuyu system, blocking the highway fuel after ignition off. It performs functions similar to the electromagnetic valve 7 off the fuel supply of the primary chamber.
Main metering system
secondary chamber (GDS-2) including an em ¬: main jet 21, main air jet and distribution pylitel 4. SDS-2 starts sounding the fuel with a significant opening of the secondary throttle valve 17 when the vacuum in the diffuser, cos ¬ given by the air flow is sufficient to lift ¬ but the fuel to the level of the mouth of the gun and received it in the air path. The fuel nozzle of the secondary chamber has a larger flow area, which ultimately provides the cardinality of the mixture, becoming in turn the work of the secondary chamber
Thus, secondary camera car ¬ byuratora acts as an air-fuel economizer, on the one hand ¬, increasing the content of engines ¬ la, on the other - enriching the fuel-air mixture.
The transition system of secondary ka-measures included after the main metering ¬ gravitating system has a main jet 19, air jet, the electron ¬ electromagnetic shutoff valve pod ¬ chi fuel 3 and the hole at the outlet of the air path in the secondary chamber zonedrosselnoy flap 17. With a slight opening of the secondary throttle Noah ¬ 17 ¬ tion thinness in the secondary chamber nozzle 4 is not enough to lift the fuel spray to the mouth and feed it into the intake tract. At the same time the beginning of opening the secondary throttle for ¬ slonki reduces air flow through the primary chamber car ¬ byuratora that causes a decrease in time ¬ rarefaction in the diffuser and hence ¬ but reduced fuel consumption through the primary chamber and a general impoverishment of the mixture.
The transitional system prevents pereobednenie mixture, which can occur at the beginning of opening the secondary throttle ¬ Noah. When fully closed Stu ¬ secondary throttle outlet passage ¬ dimensional system is higher for slonki ¬ - in a high-pressure fuel on it and do not do that. But with a slight throttle the secondary chamber exit ne ¬ Transitional system is in a high vacuum, and it begins to flow through the fuel in the air ¬ ny tract, preventing the impoverishment of the mixture.
Corrector of the mixture of prog ¬ motor 20 also includes a secondary camera. When the engine warms up corrector provides air flow from the secondary chamber mezhdiffuzornogo space directly ¬ rectly to the pro ¬ zadrosselnoe space that leads to a general impoverishment of the mixture. Economizer system provides a stepwise enrichment of the mixture with increasing engine load (throttle). Sys ¬ subject of the economizer includes a valve piston 12 with singer ¬ nym element 9, for controlled-throttle depression. Ekonomay ¬ zer included in the primary chamber ¬ byuratora car, and its valve 12 included pa ¬ parallel to the main fuel zhik ¬ Leroux, 12, and delivers fuel directly into the fuel ¬ tively tract SDS-1. Economizer valve opens under the action of ¬ viem lowering springs cast-similar rarefaction lyayuschego dilution depends on the initial positive zheniya ¬ ¬ ki barrier throttle and the engine speed. When the engine speed reduction dilution (increasing pressure) required for operation of the economizer, dos ¬ Tiga with a larger opening Drosia ¬ selnoy flap. This fact provides an early (at lower of covering the primary throttle ¬ ¬ ki barrier) the inclusion of vacuum ekonomayze ¬ pa at low speeds, which is important when overclocking engine. Accelerator pump system to prevent possible depletion of the fuel-air mixture with rapid throttle. PRIE ¬ mistost engine is determined by its ability to quickly increase capacity in the fast moving body (for throttle ¬ slonki). With the rapid opening of Drosia ¬ selnoy flap is a rapid increase in air flow and, consequently, ¬ quently, a rapid increase in resolution ¬ motion in the diffuser, which increases the flow of fuel through the spray. In the diffuser, fuel spray and partially evaporates. Couples and small droplets of fuel are pulling ¬ air flow and with it quickly reaches the cylinder engines. But part of the fuel (sometimes up to 25%) due to various factors ¬ ditch deposited on the walls of the inlet labor ¬ boprovoda as the fuel of the film, whose rate is much lower than the rate of fuel-air flow. This part of the fuel reaches the cylinder with a considerable delay, causing a temporary depletion of the mixture and the corresponding ¬ sponding reduction or delay in ¬ crease in the engine that drives ¬ to a reduction in throttle response. Accelerator pump eliminates this delay short-term feeding of an additional fuel, which leads to the desired enrichment of the mixture. The accelerator pump has been ¬ Shen 1, kinematically connected to the throttle through the pressure-ing the bar and a spring-ny blower valve 2 (gravity), installed at the output of the fuel line of the accelerator pump, reverse (or inlet) valve, which cut ¬ Th fuel from the float chamber enters the working cavity of the accelerator pump and the nozzle (spray), through which fuel enters the air tract carbo ¬ operator. With a slow throttle fuel from pa ¬ bochey cavity (podporshnevogo pro ¬ space) through a check valve mustache ¬ sang to flow into the float ¬ ka measure, increasing the pressure in the
cavity is not enough to open the discharge valve 2. In the fast ¬ rum throttle piston compresses the accelerator pump ¬ Mast fuel in the working chamber; increasing pressure from the discharge valve overlapping ¬ 2, and injects fuel through the nozzle in ¬ Xia annular gap between large and small cones of the primary measures ka-carb.
The air intake valve 5 is intended to facilitate engine starting at low temperature cooling fluid. Under these conditions, due to low hour ¬ quency of rotation of the crankshaft when turning the starter in the WLS ¬ sknom pipeline is a low ¬ some depression, which leads to retarded ¬ ciently supply of fuel through the basics ¬ nye metering system. Also because of the low wall temperature inlet ¬ Nogo pipeline engine cylinders ¬ telya mixture reaches a low-paros holding, which also makes it difficult for the engine start ¬. The air intake valve 5, with cold start re ¬ tract overlapping air chambers of the primary carburetor, with the benefit of giving ¬ kinematic connection with the throttle valve-tion is a partial priotkryvanie last. This increase ¬ creases vacuum in the intake pipe, wire and provides the fuel va ¬ through SDS-1 and the system idle ho ¬ so, creating the necessary startup enrichment mixture. Immediately after starting the engine, by contrast, must be at ¬ open the choke, throttle closing to avoid a change of notation ¬ enrichment mixture. Further ¬ tion opening the choke should prois-go gradually as the engine warms up. These features satisfied ¬ nyayutsya automatic choke control, which has 3 channels of control. The first control system excited ¬ air damper includes a bimetallic coil, altering its position ¬ schuyu with temperature and connected to the choke rod, an electric heater and a ceramic thermo ¬ stat. Immediately after starting the engine at the terminals of the heater bimetal helix appears ¬ ¬ tion voltage, which leads to heating of the bimetal-metallic spiral, spiraling, and its gradual opening of the choke. This system also (thanks to the thermal inertia of the "thermostat") prevents the open ¬ Thies air flap briefly ¬ temporary stops the engine.