DE1187065B - Metering and mixing device for the fuel in intake manifold injection internal combustion engines - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

F02f

German class: 46c2-87

Number: 1187 065

File number: R 269201 a / 46 c2

Filing date: December 11, 1959

Opening day: February 11, 1965

The invention relates to a device for the continuous pressure atomization of fuel into the intake manifold of an internal combustion engine, in which a metering and atomizing nozzle at the same time and a supply line for primary air are provided, the nozzle and the end piece of the line for the primary air are arranged in a block and open into a sliding surface that is controlled by a control slide to change the flow cross-section of the metering atomizer nozzle is ground, whose The interior has a fuel-primary air mixing chamber, with one in each case being interposed Cutting edge web on the one hand a compression spring on the control slide and on the other hand a rotatably mounted Supports lever on which a device for adjusting the control slide engages. The invention relates specifically to the improvement of such a device as described in patent 1,145,857 is. The present invention aims to provide the device according to this patent with an automatic Control system are provided. The problem to be solved is essentially the control system to be combined with the actual injection device to form a structural unit.

In a known other device, in which however, no control slide valve for the metering nozzle, but a needle valve is provided the atomizer on the one hand and the metering nozzle on the other hand structurally separated from one another. Each Control element forms its own component to be assembled separately, with the control elements and the actual injection device are connected by lines. This multitude of separate components, which can be completed quickly with the addition of a starter valve and a vacuum unit Closing the atomizer nozzle in the event of a strong intake manifold vacuum would still increase, which is a cumbersome process Assembly and a large space requirement of the device.

According to the present invention, the block, the control slide, the compression spring and the lever are in a housing with parallel side walls that guide the moving parts between them, Furthermore, the housing is attached to the intake manifold and the interior of the housing is connected to the interior of the intake manifold and are a change in the air-fuel ratio causing control organs in the End wall of the housing and / or arranged in the block and provided with transmission members that are displaceable parallel to the housing side walls and all engage the lever.

One has the advantage that the metering and mixing device for the
Fuel in intake manifold injection internal combustion engines

Addendum to the patent: 1145 857

Applicant:

Directed by Nationale des Usines Renault,

Billancourt, Seine (France)

Representative:

Dr.-Ing. E. Liebau, patent attorney,
Göggingen via Augsburg,
Von-Eichendorff-Str. 10

Claimed priority:

France of December 16, 1958 (781 818)

automatic control system is particularly simple in its structure, because the transmission links are all Moving control elements in a single plane and using a single lever on the metering valve act. The simple structure ensures a low susceptibility to failure and easy implementation of any repairs. The connection between the inside of the housing and the Inside the suction tube, the metering device is also designed as a vacuum chamber to which all Have control elements that are influenced by the suction pipe pressure connected immediately. Need it so no separate pressure transmission lines to be provided to each control element. This leads to, apart from the structural simplification due to the elimination of the lines, above all to an increase the speed of response due to easier transmission of pressure changes in the intake manifold. In addition, the mouth part of the control slide can be in a corresponding opening in the suction pipe move freely. So it needs the corresponding opening between this control slide and the having wall of the suction pipe because of the same pressure in the same and in the housing no seal of any kind is to be provided, which inevitably affects the mobility of the

509 508/107

3 4

Slide and thus the accuracy of the response with which the end face of the metering device

Device would affect. forms a butt joint, the contact pressure

An embodiment for a low pressure by means of two screws 34 tightened counter-

Injection system is illustrated in the drawing, holder 33 is guaranteed.

namely shows 5 that part of the intake manifold of the internal combustion

F i g. 1, the tube 31 forming the metering device in a longitudinal section contains a throttle corresponding to the line A -A in FIG. 2, flap 25, which is of conventional design and around the

F i g. 2, the metering device can be rotated along the axis 35 in cross section.

Speaking of line B-B in Figure 1, downstream of this flap is the jacket

3 shows a partial modification of FIG. 1, in which the tube is broken through by several openings:

according to the atmospheric negative pressure from the opening 36 to the slide 6 with the

Set can reach into the main pipe through an air-containing mixing chamber

closed metal capsule is replaced, leave and allow him his shifting movements.

F i g. 4 shows a diagram of the injection quantity values, from the opening 38 to in the inlet connection

to recover the fuel leakage amounts per working cycle depending on the absolute 15, the

Pressure on the valves. possibly located in the hollow chamber of the dosing

As shown in FIGS. 1 and 2, 1 is the device have accumulated, and from the öff metal block, which the supply lines 2 for the fuel voltage 37 as a connection to the Unterdrackraum.
and 3 receives for the air, the line 3 The pipe 31 is on a large part of its length via two symmetrical inlet channels 26 (FIG. 2) and is fed in particular in the injection zone of the air. The fuel supply line ends in a fuel emulsion from a jacket 39 to the calibrated bore - which forms a spray nozzle (addition of cooling water from the cooling circuit of the atomizer nozzle) 4 and surrounds it similarly to the air motor.

Feed line 3 opens on surface 5. The lever 20 is provided with a bore 40 and a slide 6 rests on this surface. This slide contains the 25 which ends in a cone 41. In this cone supports the mixing chamber 7, which is supported by a space in the shape of the spherically rounded end of a plunger of a circular, straight truncated cone, but also of 42, which is connected to the membrane 43 of a vacuum unit 44 screwed into the forehead in the form of an inclined truncated cone or a wall 24 firmly destroyed conical Umdfehungskörpers are formed is bound. On the outside air side of the membrane can. "^r> 30, a spring 45 generates a force on the leaf spring 15

The force acting on the large base of the truncated cone mediation of the lever 20. Counter-shaped Slider 6 forming circular ring surface 8 over a notch 46 of the lever 20, but without partially blocks the fuel injection nozzle 4. Normally touching this is that on the other hand, the egg flow opening of the air is only subject to the spherically rounded end of a plunger 47, the a small change in cross-section, so that the air 35 with the membrane 48 is also in the end wall occurs, the position of the vacuum slide screwed into the metering device is never slowed down also like to take. Which the small basic box 49 is firmly connected. On the same side of the The circular surface forming the surface of the truncated cone is the membrane 48 on which the plunger 47 is arranged Outlet opening 10 of the emulsion. is, there is a very soft spring 50, which is

The slide has a groove at the top and bottom, 40 on the vacuum can body and supported on the

in each of which a cutting edge web 13 and 14 engages membrane a more or less constant force

and forms the same angle with the surface 5. That exerts the effect of a pressure of about

The cutting edge web 13 is pressed on by a 0.1 at equivalent. The vacuum unit that on

Leaf spring 15, the support points of which have a stop 51 on one side from that of the other side of the membrane

Cutting edge 16 and on the other hand of a screw 17 45 which has the play in the notch 46 of the lever

are formed. The leaf spring 15 has a notch 20 determined, stands over a tube 52, an annular groove

18 so that it cannot slip sideways. 53, a channel 54, a throttle point 55 and a

The screw 17 can - by means of its counter nut 19 channel 56 in connection with the underdrack space,

be secured in their position. The annular groove 53 can be connected to the

A second screw 22 serves as a second support 50 to be connected to the outside air. The opening 57 is

point when the leaf spring 15 is closed to a certain degree by a needle valve 58, the

has reached the bend. The support point on the screw by a spring 59 seated in the hollow needle

17 is then dropped. This screw 22 is being pressed through the hole. Inside this needle valve

a lock nut 23 secured. the sub-

■ The cutting edge web 14 is pressed by means of the notch 12 55.

pressed by a lever 20 which swings around a cutting edge. In a modification, the vacuum unit 44 21 swings. The latter can be replaced by a housing 60 by means of a screw 28. This is then screwed into the end wall 24 of the housing of the dosing unit in the same way and contains a fixed device. In this way, from the metal bellows 61, which is sealingly attached to the two side end wall 24 and from two side walls 29 and 30, 60 disks 62 and 63 are welded and delimited with air geein negative pressure space. On these pages is filled. The disk 63 is attached to an end wall of the wall, also the block 1, and attached between the housing, while the disk 62 with which slide the moving parts, the lever plunger 42 is firmly connected (Fig. 3).
20, the cutting webs 13 and 14, the slide 6 and In the block 1 is a small airtight metal, the leaf spring 15. The end wall 24 of the housing 65 is welded to bellows 64, which is attached to a tube 31 with its lower end of the metering device Plate 65 is closed and the opening 66 is particularly well calibrated and smoothly connected to the channel 2 via its inner wall. and the outer wall of which has a flat surface 32. This elastically deformable cavity is therefore with

Fuel filled and completely under the pressure of the latter exposed. This membrane presses with the plate 65 on the upper side of the lever 20.

A part 67 is sealingly attached to the underside of the end wall 24 of the housing of the metering device; this carries a valve 68 of the starter, the shaft 69 of which is guided in a bore in the part 67. This valve is opened by a spring 70 and a washer 71 screwed onto the valve stem withdrew his seat.

The fuel supply line 72 is connected to the delivery side of a centrifugal pump 74 via a line 73 Link. This centrifugal pump is fed by a conventional feed pump 75, which the fuel sucks out of the container 76.

The valve 68 can communicate with the outside air channels 80, 81 with the closed Connect space of the dosing device, and the head of the valve 68 can against the lever 20 run up.

The injector works as follows:

adapt to the curve of the air filling of the engine and thus maintain the desired degree of enrichment.

The fuel jet is in the truncated cone of the mixing chamber 7 at a weak angle of incidence injected and exits from the atomization opening 10 by passing through the line 3 a Sucks in a certain amount of air. This is referred to as secondary air, which is quite a bit with the fuel

ίο forms a coarse emulsion. This emulsion refines but in the pipe 31 through the encounter with the primary air flow 27 of the engine.

The fine particles, which cannot be prevented from settling on the walls, evaporate slightly as a result of the temperature of these walls caused by the surrounding water jacket be kept at a sufficiently high temperature.

2. Case of partial encumbrances

1. Case of the engine running at full load

If you gradually close the throttle valve 25, then the absolute pressure in the pipe 31 falls below atmospheric pressure, and through the openings the throttle valve 25 is wide open, the pressure in 25 36 and 37 and the closed space of the metering tube 31 and in In the closed space of the metering device, the membrane 43 receives from the left a device is essentially the same as the additional atmospheric thrust, which results from the pressure difference spherical pressure. The spring 45 transmits a result, and presses on the lever 20 and the remaining certain force through the in the hollow cone 41 of the moving parts much more forcefully. The slide 6 dros lever 20 pushed in the plunger 42. The lever 20 30 since the passage cross section of the spray nozzle 4 transmits something by a slight pivoting movement to stronger. As long as this pressure remains in the vicinity of its support point, ie the cutting edge 21, a force of atmospheric pressure, the law applies to the cutting edge web 14, the slide 6, the adjustment of the slide and consequently the Ge cutting edge web 13 and the one between the cutting edge 16 set the injection quantity (for a given speed) and the end of the screw 17 clamped blade 35 according to the diagram in FIG. 4 spring 15. The deflection of this leaf spring can be seen in straight lines 77. If the absolute pressure is correct for the slide 6 , it becomes a weaker equilibrium (less than ρ ), ie if the position is such that it increases the outlet cross-section for pressure in the nozzle , then touches which the spray nozzle 4 defines. The adjustment of the cross-more and more sagging leaf spring 15 to the two-cut can be done by adjusting the screw 17 40 th support point at the end of the screw 22, the position secured by the lock nut 19 is regulated accordingly for this purpose. will. For a certain speed of the engine it is then detached from the end of the screw 17, the pressure of the fuel in the line 73, in its stiffness has increased, and the change in channel 2 and in the spray nozzle 4 is precisely defined. the injection quantity follows the law represented by the straight line The ratio of the fuel flow rate to the air 45 78,
Throughput is therefore prevails only by the screw 17 i _m hollow cone of the mixing chamber 7, a

set. Pressure which is essentially atmospheric

If the speed changes when the pressure is always wide open, since the opening 10 is under the throttle valve, then the pressure changes in the flow of the absolute pressure at the valves smaller Line 73 is like the square of the angular velocity 50 as the opening on the surface 5 for the inflow. For even low and medium speeds, there is still flowing outside air. Under these conditions flows

a significant amount of air through the hollow cone of the mixing chamber 7, encounters the fuel jet and produces a very fine emulsion, which changes little, and the cross-section of the nozzle 4 55 the speed of this air, the greater, the more powerful can be viewed as constant. The fuel- the negative pressure, d. H. the lower the load on the engine

this pressure becomes weak in absolute terms, and the pressure exerted on the lever 20 by the bellows 64 becomes be insignificant and the position of the slide 6

So, like the air flow rate, the same as the engine speed increase and the mixture ratio is maintained.

If the speed of the motor becomes very high, the air filling coefficient of the motor decreases, but on the other hand, the fuel pressure becomes very high. The bellows 64 acts on the balance of the lever

is. The atomization achieved is such that the emulsion from the air stream 27 with the smallest possible
Precipitation is carried away on the walls.

3. Interruption of the fuel supply line

During all the processes described above, the negative pressure on both sides of the membrane 48 is the same, 20 stronger, and the slide 6 moves the 65 in the lower part, because the pressure cell is directly with it kind that the free opening of the spray nozzle 4 is smaller in the closed space of the metering device will. In this way, the curve of the speed-dependent injection quantity per working cycle can be calculated

Connection is and in the upper part by means of the tube 52, the annular groove 53, the throttle point 55 and the

Channel 56. The valve 58 is pressed by the valve spring 59 on the edge of the opening 57, and it no air enters from outside. The equilibrium of the membrane 48 would thus be indifferent, but the spring would 50 presses the plunger 47 with the membrane 48 against the stop 51. The plunger 47 is from the notch 46 of the lever 20 detached enough so that the operation of the moving parts are not disturbed can.

If the absolute pressure decreases even further and reaches the value p ', then the spring 59 is sufficient is no longer sufficient to compensate for the resulting thrust on the cross section of the opening 57 and that Valve 58 ventilates a little. The outside air pressure now acts on the outside diameter of the valve 58, the is slightly larger than the diameter of the opening 57. The valve 58 is therefore easily lifted, and the outside air pressure is established in the annular groove 53, in line 52 and on top of diaphragm 48, but does not change that under the valve 58 prevailing pressures; because the flow cross-section in the throttle point 55 is much smaller than that Cross section of channel 56.

The plunger 47, which is firmly connected to the diaphragm 48, is therefore pushed down very violently, since the difference between the atmospheric pressure and the pressure p ' is several times greater than the pressure of the spring 50. It pushes the lever 20 in the notch 46 on, suddenly destroys the equilibrium, causes the leaf spring 15 to bend vigorously, and by adjusting the slide 6, the spray nozzle 4 is shut off.

The fuel delivery is completely interrupted, as can be seen at Tf in FIG. Of course, the selected pressure limit p 'is the pressure that occurs when, for example, the foot is lifted from the accelerator pedal in a vehicle engine and the car itself supplies the driving force, as is the case with long downhill drives or when pushing in city traffic. The complete removal or interruption of the gasoline flow is then advantageous, but only permitted if the following two conditions are met:

a) When the car and engine are slowed down sufficiently and when the engine is disengaged then the fuel must flow again and the engine idles without further intervention of the Driver can maintain. This is the case in the present case; because if at a certain position the speed of the control flap is reduced, then the absolute pressure increases to such an extent Wertp "indicates that the valve 58 in the opening direction acting resulting pressure is weaker than the force of the spring 59, the more so than After the valve is closed, the outside air pressure acts on the cross section of the opening 57.

The negative pressure is established in the pipe 52 immediately. The balance of pressures is on both sides the diaphragm 48 produced, and the spring 50 suddenly pushes the plunger 47 back against the stop 51, whereby the lever 2Θ is able to the normal position corresponding to the new absolute pressure to take it again and to restore the fuel delivery according to the straight line 78.

b) Depressing the accelerator pedal must allow immediate acceleration at all times. The description to a) retains its validity, with the difference that the absolute pressure suddenly returns to atmospheric Pressure is reached and that all of the processes mentioned take place much more quickly. The influx of the Fuel to the outlet opening 10 is instantaneous, since during the internal shut-off of the slide 6 the fuel in channel 2 was under the pressure corresponding to the engine speed.

4. Cold start

The system provided here allows a cold start regardless of the position of the throttle valve. If the throttle is left in the closed position when the starter is depressed, then the valve 68 of the starter is raised by means of its stem 69. It provides channels 80 and 81 the connection of the closed space of the dosing device with the outside air, and a A sufficiently large volume of air is fed through the pipe 31 and the openings 36 and 37 to the motor sucked in. At the same time, the valve 68 presses on the lever 20 in the sense that the cross section of the Spray nozzle 4 seeks to increase, so that the fuel delivery per working cycle is greater than the normal Is enrichment. Since, despite the closed position of the throttle valve, there is a sufficient amount of mixture flows in, the engine runs smoothly. It is not elaborated on how the valve stem is 69 is acted upon.

If, on the other hand, the throttle valve 25 is kept wide open, then the first lifting of the valve 68 changes not the amount of air admitted to the engine, but the pressure of this valve 68 on the lever 20 increases as beforehand the enrichment of the mixture even under full load conditions.

5. Temperature and altitude correction

If the pressure cell 44 is replaced by the pressure cell 60 (FIG. 3), then the absolute pressure is reversed the metal bellows 61 around, while inside this bellows essentially the original The pressure is close to the original outside air pressure and the respective outside air pressure is independent. When the temperature increases, the plunger 42 is pushed to the right and the injection quantity is reduced. If the leaf spring 15 only had a single support point, then it would be the injection quantity correction brought about in this way by a change in temperature and altitude independent of the load, while theoretically it should be proportional to the load; but the use two successive support points for different loads, i.e. the application of two The laws for the fuel delivery represented by the straight lines 77 and 78 lead for each of these two Set a different temperature and altitude correction, which is a good approximation for the value of the correction in all load conditions.

Outside air inlets are repeatedly mentioned above, for example those flowing in through the channels 26 Emulsion air, the starter air introduced through channel 81 and that introduced through opening 57 Air to interrupt the fuel flow. Of course, these different air inlets, although this is not shown in the drawing, in a single inlet line before the Throttle valve 25 be combined in such a way that they are

can be kept essentially at the outside air pressure, but can receive a filtered air.

Claims (6)

Patent claims: 1. Device for continuous pressure atomization of fuel into the intake manifold of a Internal combustion engine, in which a metering and at the same time atomizer nozzle and a supply line are provided for primary air, the nozzle and the end piece of the line for the primary air are arranged in a block and open into a sliding surface, which is from a control slide for Changing the flow cross-section of the metering atomizer nozzle is ground, whose Inside has a fuel-primary air mixing chamber, with each being interposed a cutting edge web on the one hand on the control slide a compression spring and on the other hand a rotatably mounted Lever is supported on which a device for adjusting the control slide engages, according to patent 1 145 857, characterized in that that the block (1), the control slide (6), the compression spring and the lever (20) in a housing with parallel, the movable Parts are arranged between leading side walls (29, 30), the housing on the suction pipe is attached, the interior of the housing is connected to the interior of the intake manifold and a change the fuel-air ratio causing control elements (44, 49, 64, 68) in the End wall (24) of the housing and / or arranged in the block (1) and with transmission members (42, 47, 65, 69) are provided, which are displaceable parallel to the housing side walls and all engage the lever (20). 2. Device according to claim 1, characterized in that that in the end wall (24) of the housing a known vacuum unit (44) with a membrane (43) and a plunger (42) connected to it is inserted in such a way and so is designed that the membrane (43) in a known manner on the one hand from the pressure inside the housing and on the other hand from atmospheric pressure or the pressure of a constant volume of air enclosed in a bellows is acted upon, the plunger resting with its free end on the lever (20). 3. Apparatus according to claim I _3, characterized in that in the end wall (24) of the housing a further vacuum unit (49) is inserted such that normally both sides of its membrane (48) are acted upon by the pressure inside the housing, with the membrane a plunger (47) is connected, the end of which is normally located a short distance from the lever (20), and a valve (58) is provided, which when the pressure in the housing drops below a certain value (p ') the atmospheric pressure access to a Membrane side granted in such a way that, as a result of the deflection of the membrane, the plunger rests against the lever and pivots it while the control slide (6) is completely closed. 4. Apparatus according to claim 1, characterized in that in the block (1) an elastic Bellows (64), the interior of which is connected to the fuel supply line (2), is inserted and the capsule is supported on the lever (20) in such a way that when the fuel pressure increases, the Control slide (6) in the sense of a reduction in the flow cross section of the metering atomizer nozzle (4) is moved. 5. Apparatus according to claim 1, characterized in that a starter valve (68) is inserted into the end wall (24) of the housing, the valve body of which rests against the lever (20) when the valve is released and this in the sense of increasing the flow cross-section of the metering - Atomizer nozzle (4) pivoted, the valve at the same time allowing a sufficient amount of air to flow into the interior of the housing and thus into the suction tube. 6. The device according to claim 1, wherein the compression spring is designed as a leaf spring, the is supported on a stop, characterized in that a second in addition to the stop Stop is inserted into the end wall (24) of the housing and arranged so that the spring stiffness increases when the spring after support at the first stop to the second stop. Considered publications:
U.S. Patent No. 2,489,214. 1 sheet of drawings 509 508/107 2.65 © Bundesdruckerei Berlin