SU1437548A1 - Carburettor for internal combustion engine - Google Patents

Abstract

The invention relates to engine building and improves the fuel efficiency of the carburetor by improving the smoothness of the regulation of engine loads in the area of fry. The actuator 4 of the throttle valve 3 is installed in the fuel-air path 2 and divides it into my throttle and pre-throttle space.

Description

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equipped with a sector 21 with a protrusion and a lever. The jet (g) 11 of a constant cross section is placed in the bypass channel (OK) 5 of the idling system. The means 7 for throttling the flow in the OK is provided with a return spring 15, a sensing element and a pneumatic actuator 8 o. The latter is made in the form of a working cavity divided by a diaphragm into two chambers. One of the chambers communicates with the atmosphere, and the other through F 11 with throttling space and through Ж 13 variable cross sections - with supracrosis space. The regulating body W 13 is made in the form of a tapered needle 19 placed in W 13 with the possibility of contact with you.

This invention relates to mechanical engineering, in particular to carburetors for an internal combustion engine.

The purpose of the invention is to improve fuel efficiency by improving the smoothness of controlling the filling in engine loadings in one.

FIG. 1 shows a schematic diagram of the proposed carburetor; in FIG. 2, a kinematic diagram of the elements of the drives is viewed from the side; on fit, 3 — kinematic drive diagram, plan view; on flash 4 shows an embodiment of a variable section jet with a regulator.

The carburetor (Fig. 1) contains body 1, in which the main fuel-air path 2 is made with the means installed in it before throttling the flow in the form of, for example, a locking throttle 3 connected to the control pedal through the drive 4 (on Fig. 4 Pogasan conditionally) In case 1, the bypass channel 5 of the autonomous idle system is also complete, with which the fuel-watering cell 6 is connected and on which means 7 is installed before throttling the flow with the profiled tip is rigidly connected with the sensitive organ mon vmoprivoda 8 constructed as a diaphragm, distupom, and is provided with means to completely overlap F 13, designed as a spring-loaded valve with a soft sealing member. The device for adjusting the minimum cross section OK is made in the form of a sensing organ, with a stem of an adjusting nut 16 placed on the rod, and a protrusion 17 on the body of the pneumatic actuator. With such a performance at low revs, controlled throttling of only OK, which ensures maximum air flow, is emptied. As the gap between the slot and the lever is exhausted, the last turn is. The shutter is open. 2 з.п f-ly, 4 Il.

The afragma which divides its working cavity into two chambers, one of which is connected through the opening 9 with the atmosphere, and the second chamber 10 communicates through the fixed section nozzle 11 with the throttling space of the main fuel / air train 2 and through channel 12, the nozzle 13 variable section and channel 14 - with over-

its throttling space. Means 7 for throttling the flow in the bypass channel 5 are provided with a return spring 15, which creates a force in the direction of its opening, as well as

a device for adjusting the minimum segment-1 of the bypass channel when adjusting a small part of the rotation when the engine is idling, which consists of an adjusting nut 16 and

the protrusion 17 on the body of the pneumatic actuator 8,} Variable section kicker 13 is installed in the housing 18 and provided with a regulator, for example, in the form of a conical needle 19 connected to the drive pedal drive 20 through a kinematic element made in the form of a sector 21 with a protrusion 23 for contact with needle 19. Sector 21 is mounted on a sleeve and has the ability

independent rotation (at a certain angle) from the bc of the throttle 3, for which it is made

thread 23, slot 23 includes the bent end of lever 24 rigidly connected to the axis of the throttle valve 3 and being an element of the drive 4. With sector 21 there is a cable 25 for the accelerator pedal. Sector 21 is also provided with a closing spring 26 returning it to its original position with the three released gas pedals. The tapered needle 19 is provided with a spring 27, which presses its end to the projection 22 of sector 21. Sector 21 (being a control pedal actuator element) is installed with contact with lever 24 (is a throttle actuator actuator element) through the radial walls of the slot 23, and the release of the foot control pedal between the mentioned drive elements is an If gap; the piston 24 is also provided with a stop 28, designed to completely close the throttle valve 3.

The parameters of the individual components of the carburetor must satisfy a number of conditions. Thus, the effective area of the diaphragm, which determines the lagging force acting in the direction of closure; the pressure regulator 7 for throttling, as well as the characteristics of the spring 15, are chosen so that the adjusting nut 16 is fitted to the protrusion 17 at the throttling space; somewhat smaller than the negative pressure corresponding to the idling speed. This applies a spring 15 with the possibility of a flatter characteristic. In addition, the moment from the force of the closing spring 26 of sector 21 on the protrusion 22 to ensure a clear return of the kinematics to its original position must obviously exceed the moment from the EFFORT of the spring 27 of the tapered needle 19 on the protrusion 22.

The carburetor works as follows

When the engine is stopped and the drive pedal 20 is released, the control pedal pressure in both chambers of the pneumatic actuator 8 is atmospheric and under the action of the return spring 15 the means / for throttling completely opens the cross section of the bypass channel 5 Throttle valve 3 of the main heating and air tract 2 is completely closed and between the drive element ( lever 24) and the drive element ne

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15

20

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gave control (slot 23 of sector 21) there is an if gap. The protrusion 22 of the sector 21, which is in the extreme position under the action of the shrunk rod 7KINA 26, overcoming the force of the rod rod 27 of the tapered needle 19, holds the latter in a patheshaw corresponding to the slightly open state of the variable-section orifice 13,

Due to the open cross section of the bypass channel 5, the engine is started with an increased filling of the cylinders, which contributes to a reduction in the starting time of both the cold and the warm up engine. After starting the engine (without pressing the control pedal), the vacuum generated in the carburettor space is transferred to the chamber 10 of the diaphragm actuator 8 through a constant-section nozzle 11. At the same time, the absolute value of the vacuum in chamber 10 is somewhat smaller than in the backsplash space, since there is a connection of chamber 10 through channel 14, slightly open the variable section jet nozzle 13 and channel 12 with the upper throttle space of the primary air-flow section 2. flow rates of the nozzles 11 and 13 depends on the ratio of the cross sections of these nozzles. Since the second chamber of the pneumatic actuator 8 communicates with the atmosphere through the opening 9, the pressure actuator moves the pneumatic actuator 7 to throttle in the direction of closing the bypass channel, compressing the spring 15 until the adjusting nut 16 reaches the protrusion 17, as a result whereby the flow restriction means 7 is set to the low idle speed position and the throttle valve 3 remains in the position. full shut down For this reason, the entire air flow E1 passes through the supra-throttle space of the main fuel-air duct 2 to the bypass channel 5 °.

At low idle speeds, the throttling means 7 is held in a constant position when the adjusting nut 16 is on the stop (vystsep 17), because the force from the differential pressure across the diaphragm of the actuator 8 exceeds: 5 the force from the compressed return spring

Setting the nominal low idle speed for

engines with various mechanical losses are carried out by rotating the adjusting nut 16, the movement of which along the rod of the pneumatic actuator 8 leads simultaneously to movement. means 7 for throttling the bypass channel 5 (when the engine is stopped, the gap between the end of the adjusting nut 16 and the protrusion 17 changes, thanks to

the imposed restriction on the shape of the characteristic of the return spring 15) the moment of moving. from the place of the means 7 for throttling on the pressure drop across the diaphragm is changed insignificantly

When the pedal is depressed, the actuator 20 rotates the sector 21 counterclockwise (Fig. 2), as a result of which the cone needle 19 is moved to the left following the protrusion 22 under the action of the spring 27, which leads to the opening of the variable-section oscillator 13. At the same time, the air coming from channel 14, variable-jet nozzle 13 and channel 12 in increased air from the over-thrust space reduces the pressure differential across the diaphragm of the actuator 8, resulting in means 7 for throttling under the action of spring 15 gradually opens the cross section of the bypass channel 5, increasing the filling of the engine. In this case, before the gap is selected (between the slot 23 and the throttle valve lever 24, the latter continues to remain in the closed position. air in the order of 15-30 kg / h (for disassembly of structures, carburetors with autonomous idle systems).

When the gap Lf is exhausted as the control pedal is tensioned, sector 21 begins to turn lever 24, opening throttle valve 3, and then the carburetor is controlled in the usual way.

Possible options for the performance of the carburetor. So, in principle, variable-jet jet with a regulating

the organ can be connected with any of the kinematic elements of the pedal of the adjustments; the organ (the cone needle 19) can be equipped with a means for completely blocking the jet of variable cross section (fig. 4) when the drive pedal is released, which makes the movement of the means 7 for pressure drop throttling. In this case, a valve 29 is installed on the tapered needle 19, for example, in the form of a rubber washer supported on a movable washer 30 loaded with a spring 31. With this design, when the drive pedal is released and the protrusion 22 of the sector 21 is released on the needle 19, the valve 29 completely overlaps the cross section the jet 13.

Claims (1)

1. A carburetor for an internal combustion engine, containing a motorized throttle valve installed in the fuel-air path and separating the latter into throttle and pre-throttle space, an autonomous idling system with a bypass channel equipped with a constant-jet nozzle and means for throttling the flow equipped a device for adjusting the minimum cross-section of the bypass channel, the throttle actuator being provided with a sector with a protrusion and a lever, characterized in that increase fuel efficiency by improving smoothness of filling control in the area of low engine loads, the carburetor is additionally equipped with regulator C; variable cross-section kicker; means for throttling the flow in the bypass channel are equipped with a return spring, a sensitive element and a pneumatic actuator, shaped as a working cavity, divided by a diaphragm into two chambers, one of which is connected to the atmosphere, and the second is communicated through a jet of constant cross section with a throttling space stvom and through the orifice of variable section - with naddrosselnym space, the regulator is designed as a conical needle housed in the nozzle of variable section to be in contact with the projection sector. Kpedali gas 2 R 23 FIG. 2 fi.Z