DE2326083A1 - DEVICE FOR REGULATING THE FUEL-AIR RATIO OF AN ENGINE - Google Patents

Description

Hamburg, May 16, 1973 139173> .1094

Priority: May 19, 1972, USA, Pat. 254

Applicant:

Caterpillar Tractor Go.
Peoria ·, III., USA

Device for regulating the fuel-air ratio

of an engine

The invention relates to a device for regulating the fuel-air ratio of an engine. The invention is mainly based on an override or superposition of a control device of the motor to an increase in fuel delivery to the engine during a decrease in the air pressure in the suction line. Pre-compression engines, and in particular Engines with exhaust gas driven superchargers generate strong and uncomfortable when accelerating quickly Tailpipe emissions. This is because the

309849/0543

_ ρ - '

Adjustment element for .the fuel supply of the engine can be moved faster than the acceleration of the motor and also faster than the pre-compressor can generate an amount of compressed air necessary for the combustion of all injected fuel is sufficient. This results in the discharge of large amounts of unburned fuel as an exhaust cloud.

Another disadvantage of the motors equipped with superchargers of the type mentioned above is that these soot heavily under load. This case occurs when the resistance or the load on the motor is so far increases that the engine speed λΐηΐβΓ den The value displayed by the controller setting decreases. Under these conditions the motor controller tries the Motor speed indicated by the controller setting to be achieved again by the fact that he automatically adjusts the fuel adjusting member so that more "fuel is fed. Due to the decrease caused by the reduced engine speed At the speed of the supercharger, however, too little air is supplied to the engine for complete combustion of the additionally injected fuel.

309649/064 * 3

_ 3 -

The US patent 2 76? ? O0 (Parks) shows a system in which the problems described above are to be circumvented by using a pressure-dependent. Mechanism which is counteracted by a spring member and which interacts with a fuel adjusting member and holds it back with the help of a movable stop «, in the event of a pressure loss in the suction line x-jird in this known Arrangement of the movable stop by the! Spring member moves and thus adjusted the fuel control member in a position of reduced fuel supply. When the air pressure in the suction line rises again, the pressure-dependent mechanism pushes the spring link together and the Haugbregler spring moves then the movable stop and the fuel inlet, actuator in a position of increased fuel supply.

'The known device works theoretically, however, this type of air-fuel ratio control has been found to have certain limitations the overall efficiency of the engine. At first it is difficult to have enough power to start the engine. to feed material, because the! spring link the movable stop and the fuel adjusting member in one position

306849/0643

Reduced fuel supply holds- Furthermore, the Eeglerfeder can fulfill their main purpose, to maintain the engine speed at * As the load increases or to increase the engine speed, the fuel adjustment member into a Move to the increased fuel supply position. Simultaneously the spring member, which is in interaction with the pressure-dependent mechanism, must be sufficient Apply force to hold the regulator spring back until the pressure sensitive mechanism is blown by the air pressure in the suction line is operated. If the preload of the spring link is greater than that of the regulator spring, but the acceleration of the engine is in one for the Efficiency of the engine harmful extent -prevented. When the biasing force of the spring member is lower than the bias acting on the governor spring, the fuel adjusting member is set by the movable stop not held back correctly, so that the acceleration of the engine grows, but at the same time an excessive fuel supply and an unpleasant cloud of exhaust gases occurs. Thus, it is necessary to make the initial bias on the spring member larger than that on the regulator spring, and a stop assembly must be seen which makes it possible to apply a predetermined preload. The fuel adjusting member can

3ÖS849 / ÖS43

move to a position with increased fuel supply » before it comes into engagement with the movable stop. Because the regulator spring is allowed to Fuel adjuster to a reduced position Moved fuel supply, the spring member generates a sufficient braking or restraint force until the acting force of the spring member is counteracted by an increasing air pressure in the intake line. So it's a compromise between acceleration and the exhaust gas development of the engine.

Under certain conditions, for example if'von When accelerating at a low speed with light load, so is a supercharger typically that the air is supplied to the intake line with a delay. This leads to the appearance of a negative Tue-ucks in the suction line. The ones identified in the above Control device for the air-fuel ratio described in the patent could not respond to such a negative suction pressure because the pressure-dependent Mechanism in the known device usually acts against an adjustable stop, which acts first used to determine the bias of the spring link is.

309849/0543

- b -

"The subject matter of Patent 3,077,873 (Parks et al) - avoids some of the disadvantages described above by providing a servo mechanism which has a movable member which acts on a valve member, while a pressure-dependent Mechanism acts on a valve spool. A hydraulic fluid pressure is used to create ' Establishing a balance of forces between the regulator spring, the spring member and that of the compressed air intake dependent mechanism, by using the servo unit it is possible to keep the spring link in balance to hold and thus a better response or a better counteraction when interacting with the pressure-dependent Mechanism to achieve. The main disadvantage of this device, however, is the required Maintenance and hardening of a servo piston, which is a separate structural unit, and in use a movable intermediate member for controlling the valve. This leads to a complex and proportionate expensive construction of the known facility.

The invention therefore aims to provide an improved control device for the fuel-air ratio, which is overridden or superimposed on the controller

"3OPY

309849/0643

and the injection of fuel into an engine,

'in particular a motor with pre-compression or a' T "

over-compressed engine, in a precise ratio. ' to that available in the intake line of the engine

standing air pressure controls to provide a full ''

Combustion of the fuel by the engine to j

laundri hr afford '·' j

Another purpose of the invention is to provide an improved control device Ir the air-fuel ratio, which is superimposed a controller, and responsive to the air pressure in Ans aug-Vert ei lungs- - \ pipe and on 'the Mo to ro eidruck responds, where the;

Control device automatically allows unrestricted movement of the fuel adjusting member of the engine during of starting to ensure that there is sufficient fuel for a reliable start of the

- Motor is available, which however afterwards i active the injection of the fuel into the engine! reduced exactly to the value required for the operation of the j. Motor is required with the greatest possible utilization of the efficiency. '

A device according to the invention for regulating the force ·. / ■ -. fuel-air ratio for engines with pre-compression · '" has a fuel adjustment element

309849/0543

tied controller and a pre-compressor, which the engine is supplied with air through an intake duct, and the device further has one with a One-piece servo piston valve unit, which brakes with respect to the fuel adjusting member is arranged. The servo piston is actuated with the aid of a fluid pressure, which is generated by the movement a valve slide is controlled, which is displaceable so that in a part of the servo piston arranged passages are opened and closed. The valve slide is on a pressure-dependent working Mechanism attached, which is connected to the intake pipe of the engine. The back pressure of the pressure-dependent Mechanism against the inlet pressure of the suction line are opposed by spring means. When starting the machine the valve slide is in a position in which the ports of the servo piston are open, to keep the servo unit in its rest position and unrestricted actuation of the fuel adjustment member to allow. The servo unit is therefore in operation when a predetermined increase in the As soon as the air pressure is applied, it pushes the valve relative to the through channels of the servo piston and moves the The flow of hydraulic fluid to the servo piston is blocked and metered. During subsequent reductions in the

309849/0543

Intake air pressure acts the servo unit in such a way that the movement of the fuel adjusting member in Direction towards an increased fuel delivery position is braked or inhibited »The inhibition or restriction of the movement of the Fuel adjusting member prevents any disproportionate increase in fuel supply to the engine, if the one available in the suction line There is not enough air to achieve satisfactory combustion of the fuel.

The control device according to the invention can in particular advantageously Xiieise directly with the fuel adjustment member are engaged and works as a function of the intake air pressure and a fluid pressure, preferably the source pressure of the engine. The device according to the invention is in the rest position to the Withhold fuel adjustment member during engine start and remains in this position until, at which point Time at which a predetermined intake air pressure is reached. At this point the control device is moving into a position that allows the motor oil flowing through to be metered to a normal Working method of the controller and with the growth of the

309849/0543

'-. ίο -

Air pressure proportional increase in fuel supply to ensure. The control device according to the invention can be moved automatically to a position in which the dosage of the motor oil is blocked and a hydraulic lock and a positive connection between the control device and the fuel -Adjusting member is made to provide an undesirable increase safely exclude the fuel supply in each pail.

Further advantages and features of the present invention emerge from the claims and the following Description and from the drawing, explained in more detail with reference to the preferred embodiments of the invention will. Show:

I ¹ Xg. 1 shows a longitudinal section through a device according to the invention for regulating the fuel-air ratio, an intake or distribution pipe of an engine with pre-compression, a regulator, and a fuel pump mechanism of the regulating device being shown in their position when the engine is started,

309849/0543

■ - 1 '! -

FIG. 2 shows a longitudinal section through one according to the invention which is similar to that shown in FIG. 1 Fuel-air ratio control device, but without the controller and in one position when the engine is running, and

Fig. 3 is a partial longitudinal section through a modified embodiment of a erfindungsge ^ · moderate fuel / air ratio control device "

In a device described in connection with FIGS. 1 and 2, a fuel pump 10 is provided with a piston 12 which can be reciprocated vertically during operation of the engine in order to provide fuel to one of the cylinders of the engine during operation of the engine by means of an injection. line 11 to be fed, a pump being provided for each cylinder. The longitudinal movement of a formed with teeth 15 of a rack Eraftstoff-adjusting member 17 is moved an attached to the piston 12 creamed member 14 ·· The pump is _s leads to a change of the injected at each piston stroke Eraftstoffmenge on the type of a metering pump at the angular displacement of the piston 12 . -

The fuel adjusting member 17 is on an attachment 18 attached, of which a connecting "bend 19 & it one

309849/0643

at its end distant from the body ^ attached stop member. 20 protrudes. Two loW weights 22 sit on one. Yoke. 25 and are driven by a gear member 24, which is driven by the control gear, not shown of the motor mt one of the * motor speed proportional speed is threefold. is »with a bucket by. Centrifugal force- taking place outside: heat movement of the Heavily weighted parts act dawn to the left on the attachment 18 a «A spring · 26 between the attachment 18 and A flans chartig en collar 27 sets the effect of force a counterforce counteracts the borrowed weights. To recruitment A movable lever 28 is provided for a selectable bias of the spring 26.

A Lufteinlaß-Ver part he / is supplied by a motor-driven supercharger 31 compressed air. A line 32 connects the distribution pipe 30 with a chamber 35 ₅ which is formed by an intermediate piece 33 with a cover 36 fastened by screws 37. .

A control chamber 39 has an inlet 40 for connection to a pressure fluid source j, for example, the lubricating oil supply of the engine. A through port 43 connects the inlet 40 to one in the housing of the chamber 39 formed bore 44. A servo

309849 / 0S43

- 13 - '■

unit 46 has a screw bar in the bore 44 Piston part 47 and a valve device 48 formed in one piece with this, which in a Bore 50 of the housing can be moved »The Y-enfcleinriehtung "Has a protruding hatchet 49 with a at dersu. and arranged 3? flange shoulder 49a, the so is arranged that they are with the stop member 20 below is engaged under the conditions set out below. A chamber 53 with expandable volume is through a Surface 51 of the piston, a surface 52 of the housing 39 and the bore 44 is formed. From the inlet 40 can liquid via the through hole 43 and one in the housing surface 52 formed groove 54 in the hammer 55 enter. ·

A first number of through channels 56 in the valve device 48 connects the chamber 53 with a bore 62 of the servo unit. A second number of through channels 57 of the valve device 48 connect the bore 62 with an annular formed in the bore 50 Recess or annular groove 58. The annular groove 58 is on the other hand connected to a drainage channel 60 of the housing 39. Another channel 91 forms for any soft © through the Servo unit oozing fluid a ya bond with the Drain.

300849/0543

- '14 -

A valve slide 63 displaceable in the bore 62 has an annular recess 66 between two _x radially projecting lugs 64 and 65 · In the case of the in Pig. The position of the extension 64 shown in FIG. 1, the through-opening 56 is open and the extension 65 is in such a position that the channel 57 is also open and the chamber 53 is in communication with the drainage channel 60.

A threaded portion 67 of the valve slide 63 is on one cup-shaped member 68 attached. One end 69 protrudes from the threaded portion 67 of the valve spool and is provided with a pin 70 which is inserted into a slot 36a of the cover 36 engages <, a first! spring member 72 having a first spring rate is disposed between the piston 47 and the cup member 68 «a second Spring member 73 with a second spring constant is arranged between the cup member and a seat member 74. A membrane 76 is between the intermediate piece 33 and the housing 39 and is secured by the Becber member 68 supported «> One on the back of the membrane 76 arranged disc 77 "forms a seat for a third Spring member 78 which between the cover plate 36 and the disk is arranged «, Bie IFe & erconstants of the three Spring members are dimensioned so that the forces acting on the membrane are in equilibrium when in the chamber

300849/0843 ''

35 there is no pressure to cause sensitivity or amplification of the servo unit.

The operation of the device described above will now be explained in the following;

Before the engine is started, the device according to the invention takes control of the fuel-air ratio a rest position described below. The spring member 72 presses the servo unit 46 afterwards recnts, see Fig. 1, - and lifts the shoulder 49a from the Stop 20. Any counterclockwise movement of the lever 28 compresses the spring 26 and moves the fuel adjusting member 17 to the right up to one Position with excessive fuel intake. When starting or starting the engine, the valve slide 63 is in ' that position. held in which due to the equilibrium condition of the spring members acting on the membrane 76 73 and 78 a connection between the channels 55 and 57 bestent over the annular recess 66. Pressure fluid entering the chamber from inlet 40 flows through channels 56, 57 and 60, see above that the exertion of fluid pressure on the piston 47 and one caused by it, directed to the left Movement is prevented.

309849 / OSU

the speed of the engine after starting has reached a certain hone, "builds up in the partition pipe 30 an air pressure and the pressure in the Chamber 35 rises. The membrane 76 is connected to the in the. Chamber 35 is acted upon by increasing air pressure · This leads to the fact that the spring members 72 and 73 compressed and the valve slide 63 is moved to the right will. Such a movement may lead to the extension 64 covering the channels 56. Through this the liquid is prevented from flowing out of the chamber 53 and it begins to flow into the chamber 53 Build up fluid pressure, which the piston 4-7 after shifts to the left into an effective control position. During this movement to the left, the shoulder hits 4-9a the stop member 20 aif and moves the fuel adjusting member 17 in a position with reduced force. material supply, see Fig. 2. The mechanism is cocked and effective when it is in the one shown in Fig.2 Position.

When the engine is idling, the air pressure in the inlet ^ angsvverteilungsrohr 30 and in the chamber 35 together-with the bias of the spring member 78 is not sufficient, around the bias of the spring acting on the diaphragm 76

303849/0543

members 72 and 7.3 ^ u over-wind, the tent ilsehieb he 73 is then held by the membrane member 76 121 in its left position and the KoITden 47 would be in an operating position _s in which the approach 64 the channels 56 "effective" limited _s "would lüssigkeitsmenge metered from the chamber 53, to keep the KoXben 47 in its in 2 ¹ Ig. 2 dargesteirten Steirong. the channels 57 was en not mrt of Singnut 58" so that only a predetermined! and the outlet channel 60 aligned, so that drainage of the liquid would be prevented.

As described above, the IFede'r 26 is at one counterclockwise movement of the lever 28 compressed, causing a load and a movement of the fuel adjusting element I7 to the right is caused up to a position with increased fuel consumption. However, if the facility is used to Control of the fuel-air ratio in action is, the spring members 73 and 78 have the Ueigüng, the Valve slide 63 to the left, to move the servo unit 46 and the shoulder 49a therefore allow only a slight deflection of the fuel adjusting member in the direction 'to a position with increased fuel consumption "

309849 / 0S43

At the momentary occurrence of a negative pressure in the distribution line 30 and the chamber 35j ″, for example when accelerating the motor from a "low speed" with low load, the membrane 76 would be pulled to the left and consequently the servo unit 46 would be slightly in the moves in the same direction. The shoulder 49a would with the stop 20 come into engagement while the stop would try according to the requirements, move to the right ^ to the fuel supply to increase. However, if the engine torque increases would, the pressure in the chamber 35 would increase slightly and the diaphragm 76 and the valve slide move to the right. The approach 64 would release the channels 56 slightly with this movement to a Allow a metered flow of liquid from the opening and a drainage through a channel 4a to the outlet 75. The fuel actuator 17 would then pull the servo unit to the right as long as the increase of the air pressure in the chamber 35 and the valve slide 63 has been moved to the right to allow a drain to allow the liquid from the chamber 53 »

If the motor is within a given speed work area and stress area, which through

309849 / ÖS43

the]? borrowed weights of the control device is determined, provides sufficient air in the chamber 35 to. to hold the device for regulating the fuel-air ratio in a position which does not restrict the slight movements which are exerted on it by the controller when this speed is maintained. However, if the engine load has risen to a point by decreasing the engine speed, the air pressure in chamber -35 is decreased by a corresponding amount, thereby causing lug 64 to restrict passages 56 and the occurrence of S ¹ IUs fluid forces in the chamber 53 to move the piston 47 slightly to the left, so that the shoulder 49a retains the stop 20 and thus prevents a disproportionately larger amount of fuel from being injected relative to the available air When the operator moves the lever 28 to accelerate the Hotor, the stop 20 is held back by the shoulder 49a until there is enough air in the chamber 35 to allow the servo unit to move through the fuel setting member 17 to the right will.

Based on Pig. 3 is now a modified embodiment of the invention described. This execution

309849/0543

shape differs by, a different one Number, .of JFe of the links to generate a counterforce: for the air pressure-dependent membrane 76 i? L one similar to the first execution farm of the Invention. Common to both embodiments are elements. the same reference numerals · denotes .. The modified Design enables a variable preload force to exert on the diaphragm * to adjust the control device for the fuel-air ratio to meet the requirements to adapt more precisely to special engines such as will be described below.

The I spring constant of a single ^ the pressure-dependent Diaphragm counteracting! Spring is linear. The pressure in the E-size distribution line of a pre-compression engine however, does not always increase linearly. Such a deviation could briefly lead to the increasing Air pressure is temporarily reduced while the fuel adjusting member in the direction of an increased fuel supply is moved. This would lead to what is known as a secondary exhaust cloud. In the Fig.-i and 2 shown embodiment of a control device for the air-fuel ratio, prevented or limited these secondary clouds to an acceptable level on most engines. However, it was found that certain engines, the occurrence of exhaust clouds is low.

309849 / OS43

is easily above an acceptable hatred. For these motors it is necessary to connect several springs in series or an expensive one with variable ones !? Provide a spring constant in order to exert a counter-pressure on the pressure-dependent membrane. With such an arrangement it is possible to adapt the function of the sail device for the bi-fuel-III-ratio to special motor-gliar characteristics.

¥ ie J seigt ¹ Ig-3, is a first! Federglied80 z ^ jischen a Sitüglied 81 and the Kolben47 arranged ,, Bas Sitsglied 81 is a a bore 82 of the housing 39 'slidably. A second spring member 84 is disposed between the seat member 81 and a cup-shaped intermediate member 85. A third spring member 86 is arranged between a flange 88 of the cup-shaped member B5 and a further cup-shaped member 68. A fourth spring member 78 is arranged, as in the first aluminum guide form, between the end cover 06 and the disc 77. Each spring member has a special, predetermined Fe de "^ constant.

the
For the third spring link 86 it becomes constant by determining the amount clo.L- Z ^ niiot-'ngenbewogung (AusXeiikung) in relation to the v / ätirena a given period of the hotox ' operation

309849 / 0SA3

acting on the diaphragm 76 force (load) be calculates. It becomes an equation of the form ■

Deflection (^ spring link) =

used, where the constant K4- of the fourth spring member 78, deflection and load are known. This equation gives the spring constant K3 cles third spring link 86.

The spring constant required for the second spring member 84 is calculated from the amount of the rack shaft movement (Deflection) based on the force which, during a given period of engine operation, xielcher is just before the period of engine operation controlled by the third spring member 86, acts on the membrane 76 (load). Sine spring equation

Deflection of the 2nd spring was linked =

K4- + -

Ί / Κ2 + Ί / Κ5-

where K4-, deflection, load and K3 (third spring link) are known, results in the spring constant Iv2 of the., wide spring element.

309843/0543

The required spring constant of the first spring member is "calculated using the amount of deflection" based on the load on the Diaphragm 76 acts just at the point in time before the second spring member becomes effective. The spring equation

Load deflection of the 1st spring link =

1 / K2

in the K4, deflection and load are known and E3 and K2 have already been determined beforehand, the result is Spring constant-E1 of the first spring link.

In the following, the mode of operation of the embodiment of the invention shown in FIG. 3 will now be described. In the operating state, the first spring member 80 with a relatively small spring constant serves at the beginning to move the seat 81 in the bore 82 to the left. The initial air pressure in the chamber 35 *, which could be relatively small, would therefore work against a relatively soft spring. Once the _air, pressure continues to increase, the spring members 84 and with respect to the spring member 80 higher spring forces of the Fede "80 were counteract on the seat member 81, meets a stop 85 until the -Sitzglied In this time.

30984 & / 0543

point would be the wide spring member 84-, which has a slightly larger spring constant than the spring member 80 has the air pressure in dej? Counteract chamber 55. Another increase in air pressure in of the chamber 35 would compress the spring member 84- over the spring member 86, which xfiederum a higher Fed he has constant than the spring member 84-, with a Goal-determined air pressure in the chamber 35 becomes the cup-shaped Member 85 impinge on the seat member 81 and the Air pressure in the chamber 35 begins to act on the spring member 86. So you get one that can be selected continuously increasing. Fed he constant gpgen the unevenly increasing air pressure in the chamber 35

In the first embodiment, by using only one spring has a linear force against the unevenly increasing air pressure. In the modified embodiment, the use of different leads Spring constants to a linear force in combination with a geometric change in force su a "? more uniform Adjustment or adaptation to the pressure changes that occur.

The valve slide 63 also works, here in the above for

309849/0543

the first embodiment "besehriefoenen Art. Bas compression of the pedals by the drackafchängige The membrane causes a metered outflow of the liquid from the chamber 53- This causes a movement of the Fuel adjuster 7Q to the right into a Position with increased fuel supply. Due to the larger number of springs, it is possible to have a better dependency on the pressure-dependent membrane in relation to the characteristic compressed air flow of the Torir poet.

309849/0543

Claims (1)

Expectations [1. Device for supplying fuel to an engine, which is controlled by a controller and a in a first direction to increase and in a second direction to throttle the fuel supply having movable adjusting member, wherein an over he control device is provided which the regulator for optionally preventing movement of the fuel adjusting member in the first Direction is superordinate, characterized in that the superordinate control device is one in a first chamber (44) displaceable piston assembly (47) that is part of this piston assembly zur_ preventing movement of the fuel adjusting member can be brought into direct contact with this, that a membrane (76) in a second chamber (35) of the higher-level control device is movably arranged that first spring means (72) is provided between the piston assembly and the diaphragm are used to generate one in the first direction on the piston arrangement and in the second direction on the membaran preload that a device (40, 43, 54) for supplying fluid pressure to the first chamber (53) is provided, wherein the fluid pressure against the bias of the first spring means in the second direction the Eolbenanordhung acts that the basket arrangement Valve passages (56, 57) for an optionally controllable outflow of the pressure fluid the first chamber for achieving movement of the piston assembly in the first direction comprises that a Valve slide (64-) for selectable opening and closing of the valve passages - connected to the membrane (76) is that means (32) for connecting the Lufteinfeittsleitung (30) with the second chamber (35) for the supply an inlet air pressure gate are seen for moving the membrane and the valve slide in the first direction against the bias of the first spring means, that second spring means (78) for Pre-tensioning the diaphragm and the valve slide into the first direction act on the membrane, and that third spring means (73) for biasing the membrane and the Valve spool are provided in the second direction. 2. Control device according to claim 1, characterized in that that the prestress exerted on the diaphragm (76) by the second spring means (78) is essentially due to it the bias of the first and third spring means (72, 73) acting in the opposite direction on the membrane is compensated ict » 309849/0543 3. Control device according to claim. 1,. characterized, that fourth spring means are provided for biasing the membrane in the second direction » 4. Control device according to claim 3, characterized in that j that the first, third and fourth spring means are arranged in series and the membrane against that by the second spring means and the in the inlet pressure present in the second chamber (35) pressurize the membrane. 5. Control device for the fuel-air ratio an engine with a fuel setting element controlled by a regulator and a supercharger for Supply of air through an inlet manifold to the engine, characterized in that the air pressure in the inlet distribution line (30) responsive spring means and a valve arrangement (48, 63) which interacts therewith are provided is, which depends on the fluid pressure of the engine lubricant during normal, through the • ^ Regulator controlled motor operating in the direction of the Is movable spring means and vice versa, that the valve arrangement is selectively in a superimposed relationship with the! fuel setting element (17) iur generation a forced movement of the adjusting member at a 309849/0543 Reduction of the air pressure in the distribution line can be connected, but during start-up the machine arranged in a non-superimposing relationship to the adjusting element is, so that during starting according to the sailor setting a sufficient 'fuel supply exists, but after starting a "superimposition of the Ten til arrangement with the .Einstellorgan d. occurs in such a way that an optimal fuel-to-air ratio for the engine and an excessive fuel supply in the event of an intermittent occurrence reduced pressure in the inlet manifold is prevented. 6 »Control device according to claim 5j, characterized in that that the spring means consist of a membrane (76) consist of resilient material and a number of springs which are normally used in a equilibrium relationship are arranged on both sides of the membrane and which can be selected in such a way are active that the valve arrangement (48, 63) is not superimposed on the fuel adjusting element Position is held. 7. Control device according to claim 6, characterized in that 309849/0543 that the valve arrangement (4-8 _s 63) has a piston (4-7), that a valve slide (63 is "connected to the diaphragm", that the valve se he cut and the piston in a non-overlapping relationship to the fuel) Adjusting member (17) are arranged until the slide is moved in a first direction that a chamber (53) for receiving the pressurized and in a the in the second direction pressurize the piston / lubricant of the engine is provided that connecting means between the chamber and the valve slide are provided, the initial movement of the valve slide in the first direction allows movement of the piston in the second direction and movement of the valve slide in the second direction a movement of the piston in the first direction prevents and causes the piston 'with the fuel adjustment member in oner itself overlapping relationship comes into play. 8. Control device for the air-fuel ratio of an engine with a regulator »steers your fuel setting element and a pre-compressor, which supplies air to the engine through a singangs distributor line. 309849/0543 leads, characterized in that pressure responsive means (76) are connected to the input manifold (JO) are connected that an intervention sxri. see a servo unit (46) and the Fuel adjusting element ('17) can be produced, with the servo unit by the pressure of the lubricating fluid of the motor can be actuated and in one piece with a piston part (47) and a valve part (48) is carried out that 'the valve part of the servo unit a bore (62) and passages (56, 57) that one connected to the pressure-responsive means Valve slide (63) arranged displaceably in the bore and with an annular recess (66) is designed, which is used to control the hydraulic fluid flow that actuates the servo unit is displaceable with respect to the passages that jfeaermittel (72, 73) on one side of the Pressure responsive means for adjusting the annular recess with respect to de:.: · Passages such it is provided that x »year during the start of the motor a substantially unrestricted flow of pressurized fluid passes through the servo unit, the The servo unit is in its rest position and the working movement Qes fuel adjustment elements (17) is unaffected 309Β49 / 05Λ3 ■ is until a predetermined pressure increase occurs in the input distribution line (JO) an actuation of the servo unit takes place and the on Pressure responsive means related to the valve spool of the passages are displaced in such a way that the pressure fluid flow passing through the servo unit is restricted and dosed in such a way that during a reduction which then occurs of the air pressure the servo unit in such a way as to da / fuel setting element acts that its movement is inhibited and any disproportionate growth of the Fuel supply based on that in the input distribution existing air prevents isto Device according to claim 8, characterized in that the servo unit (46) has a protruding member (49) with a stop (49a) "which _{selectively comes into engagement with the setting member (17 5} 20) and inhibits its movement OK Control device according to Claim 8 _S, characterized in that the servo unit (46) is essentially - axially aligned with the fuel adjusting element (17) » 309849/0543 11. Control device according to claim 8 _S, characterized in that on opposite sides of the pressure-responsive means oppositely arranged spring means are provided, by which the pressure-responsive means are normally held in an equilibrium position » 12. Control device according to claim 11, characterized in that that the counteracting.! Federnd.ttel essentially with the servo unit and the fuel setting element are axially aligned » 13. Control device according to claim 12 _? characterized in that the spring means includes a spring with a selectably variable spring rate. 14. Control device according to claim 13 ₉ characterized in that the actuation of the spring means takes place additively and in series by the means responsive to pressure. 309849/0543