DE1119049B - Fuel injection devices intended for internal combustion engines, in particular for intake manifold injection - Google Patents

Description

Specific for internal combustion engines, especially for intake manifold injection Serving Fuel Injector The invention relates to an internal combustion engine certain fuel injection direction, in particular for intake manifold injection with a throttle valve arranged in the intake manifold of the machine, in which a reel device to change the delivery rate (he fuel injection pump depending on The operating conditions of the machine are intended primarily in Dependence on their speed, and at which the prevailing in the intake manifold Negative pressure is used as a measured variable for the actuation of the control device.

There are already fuel injection pumps known that the fuel the fuel nozzles, which are original to the ylinders of a motor vehicle internal combustion engine depending on the load on the machine, in particular depending on from the intake manifold pressure of the machine. It is also known, the fuel injection pump can also be controlled depending on the engine speed.

It is known, in the warning of the air intake duct, control openings, and Zar each, one above and one below the throttle valve, to be provided with each other connected by an I5ial. In this channel there is an intermediate pressure value a, which can be used as a speed indicator. It has now been revealed that in the known trainings there are discontinuities in the control processes dadui can show that when moving the flap, the tap openings over the Air for control purposes is diverted relatively suddenly from a pressure range be transferred into the other: This discontinuity is thereby intensified It can be seen that the associated standard uniorities also only take place after they have been overcome address a common indolence.

The present invention therefore aims to provide one by actuation de? rosselklappe controlled fuel injection device of the type described at the beginning Kind to create bder it is possible to keep the engine speed freezing pressure ratios Eat as steadily as possible, so that the fuel supply xg can also be adjusted afterwards can.

For this purpose, the divorce consists in that the: throttle valve in in itself in a way with a cavity communicating with the intake duct equipped and that this cavity through an opening; it the upstream and through an opening with the interior located downstream of the throttle valve of the suction pipe is in communication that in the cavity - at least when the throttle valve is completely or largely closed - an intermediate pressure value between the upstream and downstream spaces mentioned, which is used as the speed-indicating Measured variable for the control device is used.

Due to this arrangement, an intermediate pressure value is used as the control pressure used, its change also when moving the throttle valve through limit positions is continuous through it. This pressure value is from those at the top and the bottom the pressure prevailing on the flap, which in turn depends on the opening of the flap and the intake pressure of the engine.

This changes even with rapid movements of the throttle valve Pressure in the cavity steady and without turbulence phenomena, although the occurring Changes in pressure can be significant. The pressure in the cavity depends while the adjustments of the throttle valve also from the aspect ratio between the holes leading from the cavity on each side of the throttle valve.

In a further embodiment, the invention provides that the one control opening on the edge of the throttle is provided to be together with the other in one Control line to generate a pressure that when opening the Reduced throttle valve and increasing the air flow through the intake duct.

The control opening located on the edge of the throttle valve is useful arranged so that, when the throttle valve is opened, it moves in the downstream direction is moved.

The control opening located at the edge of the throttle valve is preferably arranged on an inclined surface when the throttle valve is in the closed position forms a small angle with respect to the wall of the intake duct.

The arrangement proposed according to the invention proves to be special advantageous if, for example, the speed of a motor is increased while the percentage of load on the machine remains unchanged, for example at an increase in speed from 1000 to 5000 rpm with the same load from 2011 / o-. Because of the lower volumetric efficiency of the machine At a higher speed, the fuel consumption of the machine per revolution will increase generally decrease in speed. Is the fuel consumption per engine revolution Controlled proportionally to the pressure, in this case a correspondingly lower pressure is required required to control the control system to achieve the desired reduced fuel supply to cause. This reduced pressure required for the regulation is shown in the cavity in the throttle valve created by the fact that the originally high The opening facing the pressure side is gradually moved into the area of low pressure while the air supply to the engine is increased due to the opening of the throttle valve without a discontinuous pressure change occurring in the throttle valve cavity.

Further design details emerge from the following Description of a preferred embodiment of the invention and the drawings. In the drawings, Fig. 1 shows the vertical section of a fuel pump according to the section line 1-1 of FIG. 2, FIG. 2 shows a section through the pump according to FIG Section line 2-2 of FIG. 1; 3, 4 and 5 are sections according to the cutting lines 3-3, 4-4 and 5-5 of Figure 1; FIG. 6 also shows the installation of the injection nozzle in the cylinder head of a motor vehicle internal combustion engine, FIG. 7 a schematic Representation of the connecting lines between tank, fuel injection pump and Injection nozzle and FIG. 8 the scheme of the air throttle valve according to the invention including Control device for the fuel injection pump.

The fuel injector shown in the drawings consists of the drive part 11 and the actual pump part arranged above it 12. The part 11 includes a drive shaft 13 and a plurality of cam-controlled Rollers 14. These rollers 14 are rotatably mounted on bearing journals 15, which in the Housing 16 are used. The housing 16 carries a flange 17 with elongated Recesses 18, with the help of which the housing 16 can be adjusted with screw bolts 19 can be connected to part 12. At its upper end is the drive shaft 13 is provided with a slot 20 in which the tongue 21 of a coupling piece 22 engages, which is rotatably mounted in the housing 16. The coupling piece 22 is also provided with an upwardly directed tongue 23 which is inserted into a slot 24 engages at the lower end of a plunger 25, around the latter continuously put in rotation.

The plunger 25 is at its lower end with a cam plate 26 provided, the a plurality of projections 27 and a plurality of therebetween Has recesses 28. A pump housing 29 with an annular flange 30 and upper and lower tubular lugs 31 and 32, respectively, is on its flange 30 by means of the already mentioned screw bolts 19 clamped between the units 11 and 12. A disk 33 is arranged below the flange 30 for sealing purposes, which can be made of fiber. A ring 14 is provided below the disk 33. A compression spring 35 inserted between the cam disk 26 in the ring 34 ensures dfor that the cam disc rests on the rollers 14, the drive shaft 1 is of the internal combustion engine 36 of the vehicle and preferably driven by its camshaft 37 ', as this only rotates as fast as the crankshaft in a known manner. A Gearwheel 38 connected to shaft 13 and a gearwheel 38 attached to camshaft 37 Gears mesh with one another, so that the shaft 13 is driven with the ha) en speed of the internal combustion engine crankshaft will.

A connection opening 40 is provided on the housing 16 and is connected to the oil pump 42 of the Maäline 36 via a pipeline 41. Connected to the connection opening 40 t is a channel 43 through which the oil is brought up to the rollers 14 and the shaft 13 for shuffling. A channel 44, also connected to the connection opening 40, conveys the lubricating oil around C sealing washer 33 to a channel 451 within the tubular extension 32 and from crt to an outer annular groove 46 of the plunger Z The fuel, for example gasoline, as it is used in the injection device, can on the outer surface of the plunger 25 above the ring>; 46 seeping down, whereby the lubricating oil standing under the pressure of the pump 42 then acts as a barrier medium in the interior 46, which prevents a wet downward flow of fuel along the tube 25 and possibly into the snorting oil of the brake engine.

The pump housing 29 is provided with inlet openings 47 and outlet openings 48 provided, which on opposite inlet openings 49 and outlet openings 50 of the Taucolbens 25 are aligned. The number of Aaßöffnungen 48 corresponds to the number of cylinders The engine 36. Each of the exhaust ports f is provided with an injector 51 connected, welc] the fuel into the internal combustion engine 36 scratches. Each of the nozzles 51 consists of a nozzle housing 52, which with the help of a line 53 mitner the Outlet ports 48 is connected. The outer body 52 has an inner bore 54 audie is designed as diverging stems 55 at its outer end. Within the In the nozzle body 52 there is a valve piston 56 which has a diverging corner Has seat 57, the @tend come to rest on the seat 55 nn. Between a shoulder surface of the nozzle body 52 and one with the piston 56 connected Sleeve 59 is a spring 48 is arranged with which the valve piston 56 resiliently on his Seat is pressed.

All nozzles 51 are arranged in the cylinder head 60 of the internal combustion engine 36, to spray the fuel into a stream of air directed towards the inlet valve 61. It will be understood that the nozzles 51, rather than through the inlet valve gaps to be sprayed into the cylinder, also further upstream of the machine intake port could be arranged.

In a cylindrical chamber 63 of the plunger 25 is a metering valve 62 arranged. This metering valve 62 consists of a cylindrical section 64 and a conical end section 65. With the help of a pin 67 is with the metering valve 62 a round metering valve head piece 66 is connected. The head piece 66 is with a upwardly extending pin 68 connected. Inside the metering valve 62 a longitudinally extending channel 69 is provided which has connection openings 70 and 71 at the lower end of the valve 62 and also with connection openings 72 in the cylindrical portion 64 of the valve 62 is in communication. The connection openings 72 are on the connection openings 73 of the plunger 25 and a connection opening 74 aligned in the tubular section 31.

The pump part 12 consists of a housing 75, which together with the housing 29 forms a fuel chamber 76. Through the housing 75 leads to an adjusting screw 77 through which the valve 62 touches. Through a The arcuate slot 78 (FIG. 2) of the housing 75 is the pin 68 already mentioned led up. -The fuel injection pump is supplied from a tank 79. The conventionally designed fuel feed pump 80 sucks the fuel via a line 81 from the tank 79 and conveys it into a fuel filter device 82, which is formed in the usual way and contains a filter 83 through which the fuel is passed through for filtration. From the fuel filter the fuel reaches a check valve 84, which is a valve disk 85, which is resiliently pressed against a valve seat with the aid of a spring 86 will. The fuel chamber 76 is arranged downstream of the check valve 84.

The plunger 25 receives in a manner to be described below its fuel from the fuel chamber 76 via the connection openings 47 to to convey it out of the pump housing 29 via the lines 53 to the nozzles 51. Depending on its rotation, the valve 62 allows a specific, variable Amount of fuel delivered by the piston 25 via a bypass line 87 to flow back to the fuel chamber 76. The shunt line 87, which in the Housing 75 can be arranged, consists of a sleeve 88, which with the help of a Spring 89 is held in connection with the connection opening 74 (Fig. 3).

Between the fuel chamber 76 and the fuel tank 79 is a Fuel return line 90 is provided, which contains a pressure control valve 91. The pressure control valve 191 consists of a pointed piston 92, which with the help of a spring 94 is resiliently pressed against a seat 93. In the piston 92 are Openings 95 are provided, which communicate with the line 90 and the fuel tank 79 stand.

In operation, the internal combustion engine 36 drives the drive shaft 13 of the Injection pump via the camshaft 37 and the gears 39 and 38, which then the shaft 13 is driven at a speed that is half that of the The crankshaft of the internal combustion engine 36. Via the coupling piece 22, the plunger piston 25 offset in rotation. Since the projections 27 and the recesses 28 of the cam plate 26 run over the rollers 14, there is a reciprocating movement of the plunger 25. It should be mentioned that in an eight-cylinder engine with eight nozzles 51 on the Cam disk 26 eight projections 27 and eight recesses 28 are provided; in order to the plunger 25 every two revolutions of the engine crankshaft is moved up and down eight times It is assumed at this point that a four-stroke machine 36 is used. If the fuel injector for a two-stroke engine is to be used, the shaft 13 is driven at the appropriate speed so that that for each revolution of the engine crankshaft there are eight reciprocating movements of the plunger 25 result.

In the fuel chamber 76, the fuel is on a relatively small scale Pressure, for example 1.4 kg / cm2 in a particular embodiment of the fuel injector, held. The fuel feed pump 80, which is directly from the internal combustion engine 36 or from an auxiliary power source, such as the electrical one System of the vehicle that is driven is constructed in the usual way and sucks the fuel from the fuel tank 79 to it through the fuel filter 82 and to promote the check valve 84 in the fuel chamber 76 and thereby the fuel in the chamber 76 under this relatively low pressure. At the valve 84 is a simple check valve that prevents the fuel from flowing back prevented from the fuel chamber 76 to the line 81.

The fuel contained in the fuel chamber 76 flows under this relatively low pressure through the openings 47 and 49 into the cylindrical Chamber 63 of the plunger 25 into it. When the plunger 25 is under the influence the rollers 14 rolling on the projections 27 moves upwards, come the Openings 49 of the plunger 25 as a result of the rotation of the plunger with the openings 47 out of register. Continued upward movement of the piston 25 thus has a compression of the fuel in the one below the valve 62 Chamber 63 result, so that the fuel through the openings 50 and one of the openings 48 and the line 53 connected there is conveyed to a nozzle 51. It is Note that the port openings 50 during continued upward movement of the plunger 25 after closing the openings 47 to one of the connection openings 48 remain aligned until the plunger 25 reaches its top dead center achieved.

The discharged via one of the lines 53 and the associated nozzle 51 Fuel is below relative when compared to the fuel pressure in chamber 76 high pressure. The pressure can for example in the order of magnitude from 14 to 70 kg / cm2 in a particular embodiment of the fuel injector lie. This pressurized fuel moves the valve piston 56 in the opposite direction the action of the spring 58 away from the seat 55 and has the consequence that the fuel is sprayed out of the nozzle 51.

To adjust the valve 62 during operation, its valve body is rotated by moving the pin 68 in the slot 78. This changes the point in time at which the pressure within the cylinder 63 is released during the upward movement of the plunger. It should be noted that one opening 74 and two openings 72 are provided, but only one of the latter two openings is effective; eight connection openings 73 are also provided. If the pin 68 is in the one limit position when it moves into the slot 78 and the valve head 66 has moved counterclockwise to its limit position, as shown in FIG. 2, it is when the plunger 25 moves upwards , one of the openings 72 in register with the openings 73 and also with the opening 74, so that all of the fuel present in the chamber 63, which is under the pressure generated by the upward movement of the piston 25, passes through the openings 71 and 70, the channel 69, the connection openings 72, 73 and 74 and the channel 87 is fed back to the fuel chamber 76.

In the opposite case, if the valve head 66 so far, as it goes, is rotated clockwise (Fig. 1) and the pin 68 at the end of the slot 78 comes to a stop, the openings 72 with the openings 73 except Register brought when the piston 25 moves upwards. In this case it can there is no fuel outflow from the cylinder 63 via the openings 72, 73 and 74, and it is the fuel under the required pressure through the openings 50 and 48 and one of the nozzles 51 discharged.

The pin 68 is in a middle position between the two previously mentioned extreme positions, in which case the pin 68 is in the Area between its two end positions is located within the slot 78, so are more or less large amounts of fuel on during the upward movement of the plunger 25, a pressure is exerted in the chamber 63 via the openings 72, 73 and 74 drained. This working method arises from the fact that in the last considered Drop openings 72 and 73 for only part of the upstroke of the plunger 25 are aligned so that when the pin 68 and valve head 66 counterclockwise (Fig. 2) are moved at the end of the upstroke more and more of the pressurized fuel via ports 72 and 73 be brought to the drain.

The control for the fuel injection pump is provided with a so-called “cam plate” 100 or “cam” for short, in which two pins 101 and 102 are attached. A guide 103 for the cam 100 is pivotably mounted on a pin 105 on the upper side 104. In the guide piece 103 there is a groove 106 in which the pin 102 carried by the cam plate 100 engages. With the aid of a pin 108 , a second guide piece 107 for the cam 100 is pivotably mounted on the surface 104. A groove 109 arranged in the guide piece 107 receives the pin 101. An arm 110 attached to the guide piece 103 serves to temporarily touch and move the guide piece 107.

A lever 111 pivotably mounted on the surface 104 with a pin 112 has a pin 113 at its end which engages in a groove 114 of the cam plate 100. The cam plate 100 is provided with a beveled cam edge 115 on which the pin 68 mentioned earlier is supported.

One pivotable on the surface 104 with the aid of a pin 117 lever 116 is supported on the control pin 68 and is against this with a compression spring 118 pressed. The lever 111 carries a projection 119, which on a curved intermediate portion 120 of the lever 116 rests.

A vacuum servomotor 121 is provided for actuating the guide 103. The servomotor 121 consists of a housing 122 and a flexible membrane 123 arranged within the housing. The membrane is connected to the guide piece 103 with the aid of a rod 124. With the aid of a spring 125, the membrane 123 and its rod 124 are pressed to the right (FIG. 8).

A vacuum servomotor 126 is provided for actuating the lever 111. The servomotor 126 consists of a housing 127 and one arranged in the housing 127 flexible membrane. The membrane 128 is connected to the lever with the aid of a link 129 111 connected via a bearing pin 130. With the help of a spring 131, the lever 111 pushed up (Fig. 8).

Between the rod 129 and the guide piece 103 is a flexible one Connection is provided, which consists of a tube 132 closed at one end and a piston 133 slidably supported therein. The piston 133 is with the help a piston rod 134 protruding from the open end of the tube and a Hinge pin 135 is connected to a bracket 136 fastened to the rod 129. That Tube 132 is pivotably mounted on guide piece 103. This pivoting bearing consists of a bracket 137 firmly connected to the guide 103 and a bracket 137 with the hinge pin 138 connecting the tube 132.

The vacuum Stelhnotore 121 and 126 are special, for Air intake system 139 of the vehicle engine leading connecting lines controlled. This system consists of a housing 140 in which there is an air duct 141 downwards extends. The usual air cleaner 142 is arranged above the air duct 141. The air duct 141 leads into the usual engine intake connection 143, which with is connected to the cylinders of the internal combustion engine.

A throttle valve 144 is arranged in the air duct 141. These Throttle valve 144 consists of a thin plate 145 which is attached to a rotatable in the housing 140 mounted throttle shaft 146 is attached. On plate 145 is an auxiliary throttle plate 147 attached, which is provided with a channel 148 in its interior. The channel 148 stands with a bore 149 provided in the shaft 146 via an opening 150 in connection. The beveled side wall 151 of the Auxiliary plate 147 has a narrow opening 152 in communication with channel 148. One Another narrow opening 13 leads from the channel 148 through the throttle valve 145 outwards into the intake manifold. The throttle lever 154 is attached to the shaft 146, which is actuated by a connecting linkage 156 from the accelerator pedal 155 of the vehicle will.

The vacuum servomotors 121 and 126 are controlled via the control openings 157, 158, 159, 160 and 161, all of which open into the air duct 141. The servomotor 121 is connected to a chamber 163 via a line 162. The chamber 163 is connected to the bore 149 of the throttle valve shaft 146, via a valve 164 to the opening 158 and via the same valve 164 also to the opening 159. The chamber 163 is also connected to the control opening 161 via valves 165 and 166 and to the control opening 160 via the valve 165. A throttle section 167 is located in the control opening 158 , a throttle section 168 in the control opening 159 and a throttle section 169 in the control opening 160.

The valve 164 includes a pointed piston 170 which the Control openings 159 and 158 with respect to the chamber 163 more or less closed. The piston 170 is actuated by a load cell 171 consisting of an accordion-like one Sheet metal housing consists, which with a depending on the temperature volume changing fluid is filled, so that the piston 170 at control openings 158 and 159 with respect to chamber 163 increase in temperature more and more blocked. The load cell 171, which is preferably based on the engine temperature responds, is expediently exposed to the temperature prevailing in the exhaust of the engine.

The valve 165 consists of a sharpened valve body 172 which is actuated by a cam 173 fastened on the throttle shaft 146. The cam 173 is designed so that the valve 165 is closed when the throttle valve 145 is moved out of the idle position over a small amount of, for example, 6 °.

The valve 166 consists of a pointed valve body 174, which is at the end of a screw 175 so that the valve body is workshop can be adjusted.

The pivoting of the guide piece 107 is controlled by a correction device 176 which is responsive to the altitude and the ambient temperature. This device consists of a load cell 177 on which an actuating rod 178 is attached, which acts on the guide piece 107 . The load cell 177 is partially filled with liquid and partially filled with gas. The liquid is temperature sensitive so as the temperature increases and the liquid expands, the rod 178 is moved to the left (FIG. 8). An actuation of the rod 178 by the forces exerted by the gas in the load cell takes place in the same direction when the altitude at which the motor is operated increases and the atmospheric pressure decreases. It should also be noted that the rod 178 is constructed in two parts and consists of a screw bolt 178a and a screwed-on sleeve 178b in order to enable adjustment. The cam 100, the guides 103 and 107 and the servomotors 126 and 121 are located in a closed housing 179. The ventilation of this housing takes place via a line 180, which ends in an opening 181 of the air intake duct 141 just below the air cleaner 142 to ensure that the same atmospheric pressure always prevails inside the housing 179 as in the air intake duct 141 below the air cleaner 142.

During operation, the vacuum adjustment motor 121 speaks before mainly due to the control openings 152 and 153 in the throttle valve 144 to which Engine speed of the vehicle. There, as previously mentioned, the bore 149 in the throttle valve shaft 146 is connected to the chamber 163, is also a direct connection to the servomotor 121 available. Due to the control openings 152 and 153 of the throttle valve 144 changes the pressure in the chamber 163 as a function of the speed or the through the amount of air conveyed through the air duct 141. The change in pressure in the chamber 163 by means of the control openings 152 and 153 happens as follows: The The control opening 153 arranged in the plate 145 is always the pure intake manifold pressure exposed. When the throttle valve 144 is closed, the opening 152 acts only the atmospheric pressure present below the air filter 142. Since the If the intake manifold pressure is lower than atmospheric pressure, there is an exchange of air from the opening 152 via the channel 148 and the opening 153 to the intake manifold 143. In this way, there is a pressure in the channel 148 which is between the two previously mentioned pressures. This pressure is unchanged across the opening 150 and the bore 149 is transferred to the chamber 163 and thus to the servomotor 121.

When the throttle valve is opened, the beveled turns Edge 151 of the throttle valve initially parallel to the wall of the air duct 141 and As a result, more and more of the intake pressure instead of the pure above the throttle valve 145 exposed to the prevailing atmospheric pressure. In this way decreases as the throttle valve 144 is moved to the open position, the flow through the openings 152 and 153 gradually so that the im The pressure prevailing in duct 148 and supplied to the servomotor 121 is steadily decreasing, until the mean pressure on the intake manifold pressure has decreased. It could it can be determined that the pressure in channel 148 is opposite to the air flow through the intake passage 141 and changes to the engine speed.

In a special embodiment it was found that good results can be obtained if the opening 152 has a diameter of 1.8 mm and the opening 153 is given a diameter of 1.7 mm. The angle y between the throttle valve end face 151 and the side wall of the air intake duct 141 was 15 ° in the idle position. At this point the angle x was between of the plate 145 and a vertical one laid through the air intake duct Level 10 °.

Due to this arrangement, the control opening 152 is when rotating the throttle valve 144 exposed more and more to the intake manifold pressure. It is still It should be mentioned that the change in pressure in channel 148 takes place quite steadily and without jumps and that the pressure depends on the engine speed changes, until the throttle valve 144 is moved approximately 35 "from its idle position.

The one directly connected to the control opening 157 of the intake port 143 Servomotor 126 is exposed to the intake pressure, which is directly dependent changes from the load on the vehicle engine. Both the responsive to the engine speed Servomotor 121 as well as servomotor 126 responsive to the machine load change the per stroke of the plunger in a manner to be described below 25 amount of fuel delivered.

It is a known fact that internal combustion engines do not work at all Speeds within their working speed range are the same volumetric Have efficiency. In other words, that during each intake stroke the amount of air sucked in becomes smaller at higher speeds than at lower speeds, and it does not necessarily demand the internal combustion engine per revolution at high speeds the same amount of fuel as at low speeds. It is also one known fact that the desired fuel-air ratio at a given Load, for example quarter load, half load or full load, not necessarily remains constant over the entire speed range.

For the reasons above, you should use the number of revolutions per revolution of the machine Amount of fuel supplied both as a function of the speed and as a function change from the load. The two influences, i.e. H. the influence of the engine speed and the influence of the machine load, are such that at accelerations, if a rich mixture is beneficial, both influences ensure that the dispensing pen 68 and the metering valve 62 in the direction of a richer mixture corresponding Position can be adjusted. Since both influences are effective in the same direction, move the mentioned control parts faster into a richer mixture corresponding position than one of the influences alone could. If for the burden the machine has reached a steady state, the pressure forces of the intake port remain constant, and then only the speed-dependent adjustment forces act to adjust the mixture as requested by the speed changes alone will.

The position of the cam 100 in the grooves 106 and 109, i. H. the vertical Position of the cam 100, as shown in FIG. 8, determines for the most part the Position of the pivotable valve pin 68, which, as previously explained, a change the delivery rate of the plunger 25 causes. The cam plate 100 is made using their guides 103 and 107 adjusted, which, as described, around their pins 105 and 108 can be pivoted.

The servomotors 126 and 121 thus move the pin 68 in a clockwise direction (FIG. 8) in order to increase the amount that the plunger 25 conveys per stroke when the load, as reflected in an increase in the intake manifold pressure, becomes greater or greater when the engine speed decreases. As previously explained, the pressure in line 162 increases as the engine speed decreases. This increasing pressure acts on the membrane 123, as a result of which the rod I24 then swivels the guide piece 103 counterclockwise around the pin 105, so that the pin 1_02 of the guide 103 moves the cam 100 to the right and thus the pin 68, as in FIG. 2 and 8 show adjusted clockwise. As a result of this adjustment, the amount of fuel delivered by the plunger piston 25 to the nozzles 51 per stroke is increased. If, in the opposite case, the air flow in the channel 141 increases with increasing engine speeds, the pressure ifi of the line 162 decreases, the spring 118 then moving the cam 100 to the left and an opposite displacement of the pin 68 results, through which the plunger from the plunger 25 fuel amount delivered per stroke is reduced.

The intake manifold pressure acts on the diaphragm 128 of the servomotor 126 via the control opening 157. From this, when the load increases and the intake manifold pressure increases, the cam 100 is moved upward via the rod 129 and the lever 111, the pins 101 and 102 sliding in the grooves 106 and 109 of the guides 103 and 107. The control pin 68 moves along the inclined cam surface 115 and is thereby pivoted in a clockwise direction, so that the amount of fuel supplied by the plunger 25 to the nozzles 51 is increased. If, in the opposite case, the load and thus also the intake pressure supplied to the diaphragm 128 decrease, the cam 100 moves in the opposite direction so that the pin 68 moves counterclockwise under the influence of the spring 118 which acts on the lever 116 moves, which then also the amount of fuel delivered by the plunger 25 per stroke is smaller.

The valve 164 and the control openings 158 and 159 have the task of the speed-dependent pressure in line 162 as a function of the warm-up, d. H. to change during the start-up of the motor at relatively low temperatures. When the engine is cold, the load cell 171, which is responsive to engine temperature, holds the Valve 170 open, which then causes the below or above the throttle valve 144 arranged control openings 158 and 159 for a pressure change in the chamber 163 care for. The opening 159 located above the throttle valve 144 is atmospheric pressure and the control opening 158, which is arranged below the throttle valve 144, corresponds to the intake manifold pressure exposed. This pressure difference results in an air flow from the Opening 159 to opening 158 via the throttle sections 167 and 168, which are approximately the have the same cross-section. The one that occurs between these two throttle sections Pressure is slightly greater than the pressure in bore 149 of throttle valve 144. If this slightly greater pressure from the throttle sections via valve 164 is fed to the chamber 163, it takes the servomotor 121 via the line 1.62 applied pressure to something, as a result of which the cam 100 then acts on the pin 68 in such a way that that the delivery rate of the plunger 25 increases slightly. It's general It is known that an engine needs more fuel when it is cold than when it is warm State. This requirement is therefore satisfied by the valve 164. When the engine has warmed up, the load cell 171 closes the valve 164. Then acts on the motor 121 the pressure generated with the throttle valve assembly 144 without this in any Way changed by the control openings 158 and 159 will.

It is expedient to make the pressure prevailing in the chamber 163 and the line 162 greater than the pressure produced by the throttle arrangement 144 when the accelerator pedal 155 is taken back relatively far. In order to meet this requirement, the valve 165 is provided, which works together with the control openings 160 and 161. The increase in pressure in line 162 acts on servomotor 121 so that it increases the delivery rate of plunger piston 25 in order to take into account the idling operation of the engine, for which a greater amount of fuel per crankshaft revolution is required in a known manner than at higher speeds.

The valve body 174 is adjusted so that the control port 161 is slightly open under all conditions. Since the control opening 160 is above and the control opening 161 is below the throttle valve 144, there is an air flow from the control opening 160 to the control opening 161 in a manner similar to the previously explained air flow between the control openings 159 and 158 165, if this is open, a pressure is transmitted which is slightly greater than the pressure prevailing in the bore 149. As a result, the pressure in the chamber 163 is slightly increased compared to the pressure produced solely by the throttle arrangement 144, and an increased delivery rate is thus also achieved by means of the plunger piston 25. Because of the valve 165, the control openings 160 and 161 only come into effect during idling operation, that is to say, for example, when the throttle valve is not moved more than 6 ° out of its idling position. The cam 1.73 is arranged so that the valve body 172 is moved into the open position when the throttle valve 144 is opened less than 6 °, so that the influence of the control openings 160 and 161 can only change the pressure in the chamber 163 when the Throttle valve 144 is less than 6 = open.

When the engine is idling, a small amount of air flows around the edge of the throttle valve 144 and through the openings 152 and 153.

In addition, air also flows from the opening 160 to the opening 161. The exact size of this air flow can be adjusted with the adjusting screw 175 in order to meter the amount of air supplied to the intake port 143 of the internal combustion engine when idling. The adjusting screw 175 and the valve piston 174 also cause pressure changes in the chamber 163 through the action of the control openings 160 and 161. These pressure changes are the main task of the adjustable valve 166 Specify the specific required idle fuel quantity for the internal combustion engine by turning the adjusting screw 175.

The task of the tube 132 and the piston 133 is to briefly increase the delivery capacity of the plunger piston 25 when the accelerator pedal 155 is depressed to accelerate the vehicle. With the opening of the throttle valve 144 caused by such a movement of the accelerator pedal 155, the intake manifold pressure supplied to the servomotor 126 increases instantaneously, as a result of which the lever 111 and the cam 100 (FIG. 8) are moved upwards and the beveled edge 115 of the cam 100 adjusts the control pin 68 clockwise to the right. However, this movement of the cam 100 is not large enough when the vehicle is accelerating, and the piston 133 therefore also acts on the closed tube 132 and via the bracket 137 on the guide 103 in order to close the latter around the pin 105 pivot. During this movement of the guide 103, the cam 100 is given a movement to the right by the pin 102. Under these conditions, the arm 110 contacts the guide 107 and causes the latter to rotate about its pin 108 in a clockwise direction. This movement of the guide 107 results in an additional movement of the cam 100 to the right via the pin 101. These movements of the guides 103 and 107 thus additionally ensure the necessary movement of the control pin 68 in the direction of a setting in which a richer mixture is supplied. The arm 110 is arranged so that the cam 100 is moved substantially to the right when accelerating, regardless of whether the cam 100 is in the lowest position shown in FIG is in an upper position, although otherwise, depending on the relative position of the cam, the influence of one of the pins 101 and 102 is greater than that of the other.

As already mentioned before, the piston 133 is freely movable in the Tube 132 fitted. The arrangement is such that the air on the piston can flow past and there is the possibility that the piston 133 at slow Acceleration processes have no particular influence on guides 103 and 107 exercises.

The influence of the approach 119 on the lever 11.6 consists in the To move control pin 68 in a position in which the plunger 25 has a lower Amount of fuel supplies when the vehicle is driving the engine. Usually goes down never lower the pressure in servomotor 126 when the engine is driving the vehicle than down to 205 mm Hg. However, if in overrun, z. B. Descent, the vehicle drives the motor, the pressure at the servomotor 126 can be reduced to a lower value for example 155 to 180 mm Hg. This pressure reduction in the servomotor 126 has the consequence that the lever 111 is moved about its pin 112 downwards and the lever 116 by means of the projection 119 counterclockwise twisted. By this pivoting of the lever 116, the control pin 68 is in a Moved position in which there is a reduced fuel supply. The cam 100 moves against the yielding spring 125 to the left to this movement of the Control pin 68 to enable. This measure will prevent excessive consumption of fuel and the harmful ones derived from unburned hydrocarbons Prevents gases from the engine exhaust.

Load cell 176 moves control pin 68 to a greater fuel delivery position as atmospheric pressure increases and ambient temperature decreases. As previously mentioned, the load cell 176 is responsive to the ambient temperature of the vehicle and also to the atmospheric pressure (and thus changes in altitude). The liquid in load cell 176 expands with increasing temperatures to move plunger 178 to the left. An expansion of the load cell 176 also takes place when the atmospheric pressure (at higher altitudes) decreases, whereby the plunger 178 is then moved in the same direction. The plunger 178 acts on the guide 107. If the plunger 178 moves to the left, the guide piece 107 pivots counterclockwise to allow the cam 100 and the metering pin 68 to move to the left under the action of the lever 116 loaded with the spring 118 . In this way, the fuel quantities supplied to the nozzles 51 with the plunger piston 25 are reduced at greater altitudes or at elevated temperatures. In the opposite case, ie at lower heights or lower temperatures, the load cell 176 increases the delivery rate of the plunger 25 to the nozzles.

The length of the plunger 178 can be adjusted by rotating the sleeve Set 178 b opposite the screw bolt 178a. The plunger 178 is thus adjustable around the position of the control pin 68 according to a desired maximum delivery rate of the plunger 25 to the nozzles 51 to set.

The pressure control valve91 has the task of keeping the fuel in the chamber 76 under the desired low pressure. As soon as the pressure in the chamber 76 rises above this desired low pressure, the piston 92 lifts off its seat 93 against the influence of the spring 94 to remove the fuel from the chamber 76 via the valve seat 93, the connection openings 95 and the line 90 to the fuel tank 79 to drain. The task of the check valve 84 is to provide a undesirable backflow from chamber 76 via filter 82 and pump 80 impede. The kickback effect is achieved in that the disc 85 with the help the spring 86 is pressed onto the valve seat.

Although above the movement of the cam 100 with reference to FIG has been described using the terms "upwards" and "downwards", it goes without saying that this was done only for the purpose of facilitating the explanation on the basis of the drawing. The surface 104 is preferably oriented approximately horizontally, as is the case for this area is also shown in the other figures.

To the claims it is noted that for the subjects of Dependent claims 5 to 14 are detached from the main idea of the invention (claim 1) Protection is not desired; in the subject matter of subclaims 2 to 4 these are exemplary embodiments of the new fuel injection device with both sides throttle valve fitted with tap holes.

Claims (1)

PATENT CLAIMS: 1. Fuel injection device intended for internal combustion engines, in particular for intake manifold injection, with a throttle valve arranged in the intake port of the machine, in which a control device is provided for changing the delivery rate of the fuel injection pump as a function of the operating conditions of the machine, including primarily as a function of its speed , and at which the negative pressure prevailing in the intake manifold is used as a measured variable for the actuation of the control device, characterized in that the throttle valve (144) is equipped in a manner known per se with a cavity (148) communicating with the intake pipe interior (141) and that this cavity communicates through an opening (152) with the upstream and through a second opening (153) with the interior of the intake pipe located downstream of the throttle valve in communication, in such a way that in the cavity (148) - at least at completely or r largely closed throttle valve - sets an intermediate pressure value between the above-mentioned upstream and downstream spaces, which serves as a speed-indicating measured variable for the control device (121). z. Fuel injection device according to Claim 1, characterized in that one control opening (152) is provided on the edge of the throttle valve (144) in order, together with the other (153), to generate a pressure in a control line (162) which is increased when the throttle valve is opened (144) and increasing the air flow through the intake duct (141). 3. Fuel injection device according to claim 2, characterized in that the control opening (152) located on the edge of the throttle valve (144) is arranged so that it is moved in the downstream direction when the throttle valve (144) is opened. 4. Fuel injection device according to claim 2 or 3, characterized in that the control opening (152) located at the edge of the throttle valve (144) is arranged on an inclined surface (151) which, when the throttle valve (144) is in the closed position, forms a small angle (y) opposite the wall of the intake duct (141). 5. Fuel injection device according to claim 1 to 4, characterized in that further control openings (158, 159), one above and one below the throttle valve (144), are provided in the air intake duct (141), which are connected to one another by a duct and via a temperature-controlled valve (170) are connected to the line (162) carrying the speed-dependent pressure, the valve (170) closing when the machine temperatures rise. 6. Fuel injection device according to claim 1 to 5, characterized in that additional control openings (160, 161), one above and one below the throttle valve (144), are provided in the air intake duct, which are connected to one another by a duct and via a dependent valve (172) controlled by the throttle valve adjustment are connected to the line (162) carrying the speed-dependent pressure, the valve (172) opening and increasing the control pressure and the delivery rate of the pump when the throttle valve is closed by more than a predetermined opening amount . 7. Fuel injection device according to claim 1 to 6, characterized in that the intake port pressure (157), which changes as a function of the load, is used as an additional control factor for the injection pump control, in order to increase the delivery rate of the pump with increasing loads. B. Fuel injection device according to claim 1 to 7, characterized in that its control is operated with two pressure medium-operated servomotors (126, 121), one of which (126) with the load-dependent intake pressure and the other (121) with the speed-dependent, to the Throttle valve openings (152, 153) tapped air pressure is applied. 9. Fuel injection device according to claim 1 to 8, characterized in that a longitudinally movable cam (100) is provided to adjust the delivery rate of the fuel pump, on which the two pressure medium servomotors (121, 126) via a first and a second guide piece ( 103, 111) , each of which is pivotably mounted at one end and engages in the cam (100) with a pin-slot connection (102/106; 113/114). 10. Fuel injection device according to claim 1 to 9, characterized in that an auxiliary device (176) responding to the ambient temperature is provided which acts on a further guide piece (107) in order to adjust the cam (100) in the sense of increasing the pump delivery rate, when the outside temperature drops. 11. Fuel injection device according to claim 10, characterized in that for actuating the further cam guide (107) a responsive to the atmospheric pressure Mlfsvorrichtung (177) is provided, which causes an adjustment of the cam (100) in the sense of a reduction in the pump delivery rate when the atmospheric pressure falls. 12. Fuel injection device according to claim 9 to 11- characterized in that between the servomotor (126) and the first cam guide (103) a resilient connection (132 to 134) is provided to the cam guide (103) initially by a greater amount in the direction an increase in the pump delivery rate when the pressure supplied to the servomotor (126) via the intake port (143) increases when the internal combustion engine (36) accelerates. 13. Fuel injection device according to claim 12, characterized in that the resilient connection consists of a closed tube (132) and a piston (133) which is freely movably mounted therein. 14. Fuel injection device according to claim 9 to 13, characterized in that an actuating arm ( 110) is arranged between the two cam guides (103, 107), the other (107) in a movement of the one (103) beyond a certain amount moved in the same direction of action. Considered publications: - German Patent No. 257 088; U.S. Patent Nos. 2,522,196, 2136,959.