EP0009475B1 - Control apparatus for diesel engines - Google Patents

Description

The invention relates to a control device for injection pumps of diesel engines with individual injection pumps or individual injection pump nozzle units, which controls the maximum delivery rate and the start of injection depending on influencing variables via control curves. The injection pumps or injection pump nozzle units can be driven in an advantageous manner by a camshaft via rocker arms.

A device of the type mentioned is known from AT-B-336 345. In this known device, a curved stop element is pivoted as a function of operating variables, which limits the maximum travel of the control rod for the delivery rate of the injection pump.

In order to achieve optimum performance in diesel engines, a number of factors, such as, for example, speed, boost pressure, engine temperature, etc., which occur during operation of the diesel engine should be taken into account. Again, these factors are intended to influence various operating variables which determine the gear of the diesel engine, such as, for example, the maximum injection quantity, the injection time, etc., and these factors are therefore called influencing variables. When the operating parameters are optimally matched to these influencing variables, an optimal gear and an optimal performance of the dieset engine are achieved, however, such an optimal matching of the operating parameters to the influencing variables presents considerable difficulties:

The invention now aims to provide a structurally simple and space-saving design of such a control device, which makes it possible in a simple manner to influence various operating variables as a function of several of the factors mentioned at the beginning. To achieve this object, the design according to the invention essentially consists in that at least one control curve serving to limit the largest optimum delivery quantity of the pump assigned to the respective operating state is arranged coaxially with at least one control curve serving to set the start of injection on a common axis or shaft. The coaxial arrangement of control cams for the limitation of the maximum control rod travel allows a simple limitation of this control rod travel in such a way that the position of the control curve comes into effect that limits the control rod travel to its lowest maximum permissible adjustment position. However, since not only the delivery limit stop, that is, the stop that limits the maximum travel of the control rod, is to be dependent on influencing variables such as the speed, the boost pressure and the engine temperature or the like, but also other operating variables such as the maxima le Injection quantity or the injection timing are influenced by partially identical factors, the coaxial arrangement of the control cams results in the advantage of significantly smaller dimensions, since the adjustment of the control cams, for example for the delivery rate limit stop and the adjustment of the injection timing, insofar as they depend on the same influencing variable, for example the speed , can be adjusted from a common adjustment path derived from the speed controller via a common component, for example a toothed rack. This reduced space requirement of the control device allows the controller according to the invention to be used for special fields of application in which conventional controllers can no longer be used for reasons of space.

In a simple manner, the design can be such that the control cams are arranged on lifting cams rotatable about the common axis, which act at least in part on a common scanning element and in accordance with the control by the influencing variables to which they are assigned, in the attack position on the latter common scanning organ. In this way, the control curve which is controlled by the influencing variable which is decisive in the relevant operating state can be brought to bear on the sensing element. For example, the setting of the limit stop limiting the maximum stroke of the control rod, by means of which, for example, an exceeding of the smoke limit is to be avoided, is not only dependent on the speed of the machine, but also on other influencing variables, such as the boost pressure and the temperature, if provided an optimal gear of the diesel engine is to be achieved. In certain operating states, the speed determines the maximum amount of fuel that can be processed. In other operating states, the maximum amount of fuel that can be processed is again dependent on the air pressure in the intake manifold, which depends on the boost pressure in diesel engines working with "charging fans and on atmospheric pressure in diesel engines without charging fans, and in other operating conditions the amount of fuel that can be processed without exceeding the ₄ smoke limit is dependent on that This maximum amount of fuel that can be processed by the engine should never be exceeded, and according to the invention the influencing variable should determine the position of the stop that limits the maximum travel of the control rod and that determines the largest amount of fuel that can be processed.

The arrangement is expediently such that the lifting cams controlled by various influencing variables and acting on a common scanning member are freely rotatable relative to one another on the common axis and, independently of one another, in accordance with the control by the influencing variables to which they are assigned, in the attack position on the common scanning organ.

According to the invention, a stop that limits the maximum stroke of the control rod can be controlled by a scanning element common to several control cams (lifting cams), onto which a control curve coupled to a speed measuring device and a control curve coupled to a pressure in the intake line of the engine or to atmospheric pressure act upon the pressure sensitive element or a control cam coupled by an operating temperature, such as cooling water temperature, oil temperature and / or temperature of the cylinder head, fuel temperature or by the outside temperature, acts on the control cam, all control cams acting in the sense of a reduction in the maximum amount of fuel that can be injected on the common scanning organ. A separate speed measuring device is preferably provided for controlling the lifting cam coupled to the speed measuring device. The lifting cams can be driven in a simple manner in that toothed segments or gears are connected coaxially to the lifting cams, which mesh with toothed racks which are adjustable by the organs registering the influencing variables.

According to the invention, one or more additional control cams are arranged on the common axis, which act on a, possibly common, separate sensing element, the latter controlling a different operating variable, control cams controlled by the same influencing variable being connected to one another in a rotationally secure manner if they are formed on lifting cams are. The rotationally secure connection of several lifting cams can be carried out by arranging them on the same axis with structurally simple means and by the fact that the lifting cams controlled by the same influencing variable are connected to one another in a rotationally secure manner, the control is simplified since now only one lifting cam of the relevant influencing variable must be controlled. An important operating variable is the timing of the injection and the arrangement can be made according to the invention in such a way that a lifting cam connected to the lifting cam coupled to the speed measuring device and preferably also a lifting cam connected to the lifting cam coupled to the temperature-sensitive element cooperates with a sensing element, which cooperates actuated an injection timing adjustable. However, since the forces acting on the sensing element, which are determined by the influencing forces, are relatively small and a spray adjuster requires greater forces for its adjustment, a hydraulic power amplifier (servo element) in the transmission mechanism is expedient according to the invention between the sensing element and the injection timing adjuster embarked.

At the start of the diesel engine, an increase in the injection quantity is necessary and the arrangement should therefore be made so that the limit stop which limits the maximum control rod travel during operation can be pushed through during the start in the sense of an increase in the maximum control rod travel and thus an increase in the injection quantity. This is made possible according to an advantageous embodiment of the invention in that the stop which limits the maximum stroke of the control rod of an injection pump is controlled by a pivoting lever which is supported against the sensing element, which pivoting lever is pivotally mounted about an eccentric element, the rotation of which causes the setting of an increased injection quantity is made possible when starting.

However, the control cams can not only be arranged on lifting cams within the scope of the invention. in many cases it can prove to be advantageous to provide rotating bodies or segments of rotating bodies, the generatrices of which are shaped in accordance with the control curve. The movement of the organ, which is adjusted by the size of the company, for example by the sleeve of a rev counter, is a reciprocating movement and when reciprocating cams are used, this reciprocating movement must be converted into a rotating movement, which in view of the elements required for this on the one hand involves a construction effort and is also a source of inaccuracies. The scanning member is a reciprocating member when using lifting cams. Such a reciprocating organ again requires a guide which, on the one hand, also requires a constructive effort and, on the other hand, impairs ease of movement. The adjustment movement of this reciprocating organ must also be implemented accordingly. According to the invention, the design is therefore preferably made such that at least some of the control curves are formed by the generatrices of a rotating body or segment of a rotating body, which rotating bodies or segments of these rotating bodies are axially displaceably mounted on the common axis, and the associated scanning element from one point on an axis parallel to the axis of the rotary body is difficult and formed in the direction of its pivot axis se immovably mounted scanning lever The storage of this rotary body on deo common axis in turn provides a structurally particularly simple storage for the Arrangement of a plurality of rotating bodies. Above all, however, an embodiment according to the invention is made possible in which at least one rocker arm has a plurality of scanning lever arms which interact with rotating bodies or segments controlled by different influencing variables. Such a design allows a company size to be regulated in a simple manner as a function of several influencing factors. This makes it possible to take advantage of the control movement of the influencing variables which result in the greatest deflection and thereby to adjust the relevant operating variable in accordance with the requirements.

The reciprocating movement of the organ moved by the influencing variable, for example by a tachometer, can be transmitted directly to the rotating body having the control cam, and the mounting of this rotating body on an axis is structurally simple. Because the generators of a rotating body form the control curve, the control is not distorted by the pivoting of the scanning lever, which comes into contact with different generators of the rotating body as a result of its pivoting, since of course all generators are of the same shape. This makes it possible to choose the length of the scanning lever short, whereby a space-saving design is achieved and it is also made possible by simple construction, since parallel axes can be accommodated and stored more easily in a control housing than crossing axes. The end of the scanning lever that comes into contact with the rotary body is expediently designed with a roller. If the roller is arranged so that its axis intersects the axis on which the scanning lever is mounted, any distortion of the control is also avoided by this roller.

According to the invention, the scanning members are expediently designed as rocker arms, which have at least one scanning lever arm forming the scanning lever and the other arm of which adjusts the organ setting the operating size, whereby a simple transfer of the control movement to the organ to be controlled is achieved.

According to the invention, for example, two interconnected rotating bodies can also be displaceably mounted as a function of the rotational speed, one of which cooperates with a scanning lever that controls the stop that limits the maximum delivery rate and the other interacts with a scanning lever that controls the start of injection. In this way, several operating variables, for example the maximum amount of fuel and the time of injection, can be controlled by the same influencing variable without any particular design effort. It is only necessary for the two rotating bodies to have generatrixes shaped according to the required control curves.

According to an advantageous embodiment of the invention, the arrangement can be such that the lever arm forming the stop limiting the maximum delivery quantity has a ramp which extends transversely to the pivot axis of this lever arm and forms the stop. As a result, the maximum limitation of the delivery rate can be achieved in a simple manner and without translating the pivoting movement of the scanning lever arm into a reciprocating movement.

When starting a diesel engine, as already mentioned, an increase in the injection quantity above the normal extent is expedient or necessary. This can now be taken into account in that, according to the invention, the rocker arm which forms or actuates the lever arm which forms the limit or limits the maximum delivery quantity is mounted on an eccentric which can be rotated for the purpose of increasing the starting filling. This rotation path of the eccentric can be limited by a stop controlled by a temperature-sensitive element influenced by the engine temperature, which takes into account the fact that a lower excess fuel is required when the engine is hot than when starting cold.

In the drawing, the invention is explained schematically using exemplary embodiments. 1 shows a simplified schematic representation of the device according to the invention, FIG. 2 shows a cross section through a structurally simple arrangement of signal transmitters and signal receivers, FIGS. 3, 4 and 5 detailed representations for the constructive design of the speed-dependent adjustment and the start quantity release in various 4, a cross-section along the line IV-IV of FIG. 3 and FIG. 4 a cross-section along the line 111-111 of FIG. 5, FIG. 6 a schematic representation of a constructive embodiment of the boost pressure-dependent adjustment, FIG. 7 shows a schematic illustration of the temperature-dependent adjustment, FIG. 8 shows a schematic illustration of the speed-dependent control of the injection adjustment, FIG. 9 shows a cross section through the servo element actuated by the device according to FIG. 8 for adjusting the injection timing, FIG. 10 shows a schematic illustration of a further embodiment the egg according to the invention 11, a section along the line XI-XI of FIG. 10 and FIG. 12 a detail of the delivery rate stop in the view according to arrow XIII of FIG. 11.

In Fig. 1 flyweights 1 are provided for adjusting the delivery quantity adjusting member or the control rod 2, these flyweights 1 being pivoted against the force of the idle spring 3 and the end regulating spring 4. Instead of a conventional regulator sleeve, a regulator sleeve rod 5 is provided here, by means of which the corresponding to the regulator sleeve movement Movement occurring in the axial direction of the axis of rotation of the centrifugal weights is transmitted to the control rod 2 via a drag spring mechanism 6 and a control lever 7. The design here is such that the regulator sleeve rod 5 is passed through a bore in the motor or pump camshaft 8. The camshaft 8 is driven by the gear 9. The regulator sleeve rod 5 engages via a coupling pin 10 on an arm of the centrifugal weights 1 and is thus displaced in the axial direction when the centrifugal weights 1 are pivoted out. The flyweights 1 are pivotally mounted on a carrier 11. In addition, centrifugal weights 12 are pivotally mounted on the carrier 11 and cooperate with a sleeve 13. The flyweights 12 and the sleeve 13 form the speed measuring device, the axial stroke of the sleeve 13 being picked up by a deflection lever 16, which is loaded by the force of a spring 17, with the interposition of a sliding disk 14 on a sliding piece 15. The bell crank 16 acts on a rack 18, the displacement of which represents an analog signal for the speed.

The camshaft 8 has cams 19 and 20 for the control of the valves and cams 21 for the actuation of the injection pump. The position of the control rod 2 can by hand, which is articulated on an axis 23, and via which the pivot axis 37 of the control lever 7 can be adjusted, by hand in the sense of an increase in the delivery rate in the direction of arrow 24 or in the sense of a reduction the delivery rate can be adjusted in the direction of arrow 25. The individual control rods 27 provided for each pump nozzle unit 26 are connected to this control rod 2, such a pump nozzle unit 26 being provided for each cylinder.

The path of the control rod 2 is limited by an adjustable delivery rate stop 28, which is acted upon by a spring 29 in the sense of increasing the permissible delivery rate. A lever 30 is in abutment with the delivery rate stop 28. The lever 30 has a roller tappet 31, the actuation of which adjusts the delivery quantity stop 28.

The rack 18, the displacement of which corresponds to the respective speed, interacts with a toothed segment 32. The toothed segment 32 is non-rotatably connected to a lifting cam 33 which represents or carries a control cam for the roller tappet 31. Furthermore, a lifting cam 34 is connected to this toothed segment 32 in a rotationally secure manner, which interacts with a counter stop 35 for the adjustment of the injection timing. The lifting cam 33 causes an adjustment of the delivery rate or full load stop 28 via the roller tappet 31 and the lever 30 as a function of the speed of the camshaft 8, and the limitation of the path of the control rod 2 in the direction of increasing quantity can thus be adapted to the respective requirements of the injection internal combustion engine which should be optimized in terms of space, torque and consumption.

The speed-dependent adjustment of the injection time is carried out in an analogous manner to the adjustment of the delivery quantity stop 28 via the deflection lever 16, the rack 18, the toothed segment 32, the lifting cam 34 and the counter stop 35 to the servo device 36, which will be described in detail later.

1, the membrane is shown in FIG. 1 and the piston of a boost pressure measuring unit, which is loaded by a spring 40, is shown in FIG. The charge pressure-dependent displacement of the membrane 38 is transmitted to a toothed rack 41, which cooperates with a toothed segment 42 mounted coaxially to the toothed segment 32. The toothed segment 42 is connected in a rotationally secure manner to a lifting cam 43, which comes into operative connection with the roller tappet 31 when the line of contact with the roller tappet 31, which is created by rotating the lifting cam 43, is at a greater radial distance from the pivot axis 44 than the greatest radial distance of the lifting cam 33 in the direction of the roller tappet 31. In this case, the limitation of the control rod travel required by the boost pressure takes priority over the limitation of the control rod travel by the speed of the camshaft and is passed on to the delivery rate stop 28 via the lever 30.

45 with the magnet for releasing the starting excess quantity is designated, by its actuation the delivery quantity stop 28 against the force of the torsion spring 46 is released in the sense of an increase in the permissible fuel quantity.

Further details of this schematic representation are shown in FIGS. 2 to 9. In Fig. 2, the reference numerals of Fig. 1 are retained and it can be seen that the toothed segments 32 and 42 are arranged coaxially pivotable about the axis 44 and are non-rotatably connected to lifting cams 33 and 43. The rack 18 causes a rotation of the lifting cam 33, which cooperates with the roller tappet 31 for the adjustment of the delivery rate stop 28 and, on the other hand, causes the adjustment of the likewise coaxially arranged lifting cam 34, which cooperates with the counter-stop 35 for adjusting the injection timing. The rack 41 effects the boost pressure-dependent adjustment of the lifting cam 43, which likewise causes the delivery stop 28 to be adjusted via the roller tappet 31. 2, the rotation of the toothed segment 42 leads to a rotational position of the lifting cam 43, in which the radial distance a of the circumference of the lifting cam 43 in the direction of the roller tappet 31 is greater than the radial one Distance of the circumference of the lifting cam 33 in the same direction, whereby the signal corresponding to the boost pressure is supplied to the delivery quantity adjusting element 28.

FIG. 2 also shows a toothed rack 47 which acts on a toothed wheel or toothed segment 48 to which a lifting cam 49 is connected in a rotationally secure manner. The rack 47 is displaced depending on a temperature measuring mechanism and the lifting cam 49 interacts with the roller tappet 31 when the circumferential curve resulting from the corresponding rotation of this lifting cam extends radially in the direction of the roller tappet over the greatest radial distances of the circumferential curve of the lifting cams 33 and 43 . In this way, the delivery rate stop 28 is adjusted as a function of speed, boost pressure or atmospheric pressure and temperature in such a way that that control cam of the lifting cams 33, 43 and 49 cooperates with the roller tappet 31, which at a specific rotational position of the corresponding lifting cams has the greatest radial distance from the common pivot axis 44, whereby each of the three separate influencing variables influences the flow rate stop which determines the largest quantity of fuel that can be processed. The largest amount of fuel that can be processed represents one of the operating parameters of a diesel engine.

Another operating variable of the diesel engine is, for example, the time of injection. The adjustment of the injection time by the counter-stop 35 is effected as a function of the speed of rotation via the cam 34, which is likewise rotatably mounted on the axis 44 coaxially. The spray adjustment can also be carried out as a function of the temperature, for which purpose a lifting cam 50 is provided which is arranged coaxially with the other lifting cams and is non-rotatably connected to the toothed segment or gear 48 via a shaft 51 and bolts 52 and 53, which in turn is connected is connected to the rack 47, which is shifted depending on the temperature. The control curve of the lifting cams 34 and 50, which results in the greater radial distance from the articulation axis 44 and is thus in operative connection with the counter-stop 35, is also relevant for the adjustment of the injection time. This design achieves a particularly compact structural design.

3, 4 and 5, the speed-dependent approximation of the limitation of the path of the delivery quantity adjusting element or the control rod 2 is shown in detail on the basis of a preferred design. In Fig. 3, the reference numerals from the previous figures are retained and the rack 18, which transmits the speed-dependent signal to the gear 32, is shown. The gear 32 sits on a speed signal shaft 54 and is non-rotatably connected to the cam 33 by a dowel pin 55. The boost pressure signal shaft 56 is arranged coaxially with the speed signal shaft 54 and carries the ring gear 42, which in turn meshes with the rack 41 of the boost pressure sensor. The lifting cam 43 is connected to the boost pressure signal shaft 56 in a rotationally secure manner by means of a dowel pin 57. A sleeve 58, which carries the lifting cam 34, is connected coaxially and in a rotationally secure manner to the speed signal shaft 54, the rotationally secure connection being secured via a pin 59. The lifting cam 34 interacts with the stop 35, which is pivotably mounted about an axis 60 and, when it is pivoted, acts on the device for adjusting the injection timing by means of a deflection shaft 61. 46 again shows the torsion spring which, after actuation of the lifting magnet 45, releases the stop plate 62, which enables start overfilling. The lifting magnet 45 has an armature 63 which is pulled downward by the magnet against the force of the spring 64. The armature 63 slides within the sleeve 65, which also receives the spring 64.

In Fig. 4, the rack 18 of the speed sensor can be seen, which is shifted via the bell crank 16 under the action of the movement of the flyweights 12 against the force of the spring 17. The bell crank 16 strikes against an adjustable bolt 66, the precise adjustment of which can be adjusted by the lock nut 67. The rack 18 meshes with the ring gear 32 of the speed signal shaft 54. Deriving the displacement path of the rack 18 from a separate speed measuring device (flyweights 12) has the advantage that the displacement path of this rod by suitable adjustment of the springs 17 or the additional spring 68, can be set separately and can be selected independently of the centrifugal weight regulator acting directly on the control rod.

In Fig. 5 it can be seen that the delivery rate stop 28 is engaged with the lever 30 which is pivotally mounted on the eccentric 69. The lever 30 has the roller tappet 31, which interacts with the lifting cams 33 and 43 and engages the delivery quantity stop 28 via a stop piece 70. The delivery quantity stop 28 is designed as a threaded rod and has a holding piece 71, on which the compression spring 29 acts. The relative position of the full load stop 28 to the stop piece 70 can be adjusted by turning the full load stop 28 after loosening the lock nut 72. When the starting quantity is released by the lifting magnet 45, the stop plate 62 is released and the lever 30 is pivoted about the eccentric 69, so that the delivery quantity stop 28 can be overpressed against the force of the spring 46 and the spring 29 until the lock nut 72 strikes the cover 73 , being a limit tion of this stroke can be made by spacers 74. After the first curtailment, i.e. when the force of the centrifugal weights 1 acting on the spring plate is greater than the counterforce of the idle spring 3 and the end regulating spring 4 due to the speed of the pump or motor camshaft 8 and thus via the gear chain - coupling pin 10, regulator sleeve rod 5 and Regulator lever 7, the delivery quantity adjustment member 2 is pulled in the direction of decreasing quantity, the eccentric shaft 69 is turned back by the torsion spring 46 and the armature 63 of the electromagnet 45, which is no longer energized, is pressed by the spring 64 in the “OFF” direction and blocks the path of the stop plate 62 again The path of the stop plate 62 in the direction of the normal operating state is limited by a screw 75. The eccentric shaft 69 is also turned back when, after the starting process, the delivery quantity adjusting member 2 is no longer pressed against the full load stop 28 because the pivotable adjusting lever 22 is no longer in the "full" position.

In Fig. 6 the detail showing the rack for the boost pressure-dependent adjustment is shown enlarged. As already described in FIG. 1, the boost pressure sensor is formed by a membrane 38 and a piston 39 loaded by the spring 40, the boost pressure or, in a corresponding embodiment, the atmospheric pressure acting on the membrane 39 via the opening 76. The rack 41 meshes with a gear 42, which sits on the boost pressure signal shaft 56, and the displacement of the rack 41 thus results in a rotation of the lifting cam 43, which in turn cooperates with the roller tappet.

FIG. 7 shows schematically the temperature-dependent adjustment of the delivery rate stop, which is not shown in FIGS. 3-6 for better clarity. Any characteristic temperature can be used as the operating variable for this adjustment, for which oil, cooling water, cylinder head or fuel temperature of the injection internal combustion engine can be mentioned. An expansion element 77 acts here as a signal transmitter, which causes the displacement of a toothed rack 47, which is already shown in FIG. 2. With this rack 47 meshes a gear 48, which is non-rotatably connected to a control cam 49. The gear 48 is in turn arranged coaxially to the speed signal or the boost pressure signal wave and the lifting cam 49 acts like the stop curves of the lifting cams 33 and 43 on the roller tappet 31, which causes the displacement of the delivery rate stop 28 via the lever 30. Due to the fact that the control cams of the lifting cams 33, 43 and 49 each act on the same roller tappet 31, if all three alignment functions are to be used, i. H. an adjustment to the speed, the boost pressure and the temperature should always take effect effectively the control curve that specifies the lowest delivery rate.

In Fig. A constructive embodiment of the adjustment of the injection timing is shown enlarged depending on the speed. The lifting cam 34, which cooperates with the counter-stop 35 for the adjustment of the injection timing, is connected in a rotationally secure manner to the speed signal shaft 54. The counter-stop 35 is pivotally connected to a spring-loaded shaft 78 arranged concentrically to this axis, the stop 35 being arranged eccentrically to the axis 60 and being connected to the shaft 78 by means of a deflection shaft 61. The shaft 78 is rotated by a torsion spring 79 in the sense that the counter stop 35 bears against the lifting cam 34. A stop piece 80 is connected in a rotationally fixed manner to the shaft 78 and carries an adjustable threaded pin 81 at its end. The set screw 81 cooperates, as shown in FIG. 9, with the control piston 82 of the servo device 36 for the adjustment of the injection timing. 8 only provides the speed-dependent influencing of the control piston 82. However, as shown in FIG. 2, a further cam with a corresponding control curve for the temperature-dependent adjustment of the injection timing can also be provided on the counter-stop 35.

9 shows the servo device for the injection timing adjustment in detail. The working piston 84 of the injection adjuster, which is designed as a follower piston, is brought into the position specified by the control piston 82 by the pressure of the engine lubricating oil of the internal combustion engine or a suitable oil pressure of an auxiliary oil circuit. For this purpose, the chamber 85 is constantly pressurized with the lubricating oil pressure. Depending on the direction of movement of the control piston 82, the chamber 86, which has a larger front end area, is either connected to the chamber 85, which causes an oil flow to the chamber 86, or by pushing the other (bottom) control edge to the non-pressurized housing space, which leads to an oil inflow Chamber 85 results.

The working piston 84 is connected via the tab 87 to a known device for adjusting the injection timing. When the engine is not running, pressure oil is generally not available. The working piston 84 is therefore held in a defined starting position by a spring 88.

In Fig. 10, the governor is designated 89. The flyweights 90 are pivotably arranged on a carrier 91 and are rotated at the camshaft speed. During rotation, the flyweights 90 compress the springs 92, 93 and 94, and a coupling pin 95 becomes one Regulator sleeve rod 96 moved when these swing out centrifugal weights. This reciprocating movement of the regulator sleeve rod 96 is transmitted, with the interposition of a trailing spring 97, to a regulator sleeve 98, to which a regulator lever 99 engages, which transmits the reciprocating movement of the regulator sleeve to a delivery quantity adjusting element 100. The control lever 99 is mounted on an eccentric 101, which can be adjusted via a hand lever 102, so that when the hand lever 102 is adjusted, the delivery quantity adjustment member 100 can be adjusted independently of the setting tapped by the control sleeve 98. The trailing spring 97 interposed between the control sleeve 98 and a spring plate 103 serves to reduce and limit the forces acting fully on the full load stop 104 or on the control rod or the delivery quantity adjusting member 100 and the lever 102 in the position.

In addition to the controller 89, which effects the adjustment of the delivery quantity adjusting member 100, a speed measuring device 105 is now provided, which has centrifugal weights 106. The centrifugal weights 106 are again pivotally mounted on the centrifugal weight carrier 91 and when these centrifugal weights 106 are pivoted, a spring 107 is compressed. The centrifugal weights 106 are here connected to a sleeve rod 109 via a coupling bolt 108 and the reciprocating movement of this sleeve rod 109 is transmitted via a bolt 110 to a lever 112 mounted in a pivot point 111. While the back and forth movement of the centrifugal force regulator 89 acting directly on the delivery quantity adjusting element is not linearly related to the rotational speed due to the various springs acting in succession, since the centrifugal force regulator 89 is also supposed to effect a final limitation, among other things, the pivoting path of the centrifugal weights 106 of the speed measuring device 105 only loaded by the force of the spring 107, so that here the displacement of the sleeve rod 109 is linearly related to the speed.

The displacement path specified by the speed measuring mechanism 105 is now intended to be effective, for example, for limiting the path of the delivery quantity adjusting member 100, and therefore a rotating body 113 is mounted on an axis 114 which is displaceable in its axial direction, the lever 112 transmitting the displacement path of the sleeve rod 109 with its bearing 111 turned away end 115 is engaged with the rotating body 113. With increasing speed, the rotating body 113 is thus displaced in the direction of arrow 116. The rotary body 113 has on its periphery control cams 117 and 118 which cooperate with the scanning members 119 designed as rocker arms for the adjustment of the delivery limit stop 104 and 120 for the adjustment of the injection timing. The rocker arms 119 and 120 are hereby pivotable on a shaft 121 parallel to the mounting of the rotating body 113 and are mounted immovably in the axial direction of this shaft 121. When the rotary body 113 is displaced in the direction of the arrow 116 along the bearing 114, the scanning rollers 122 of the swivel lever 119 and 123 of the swivel lever 120 come into contact with different positions of the control cams 118 and 117 and the delivery rate limit stop 104 or the injection timing adjustment device is influenced thereby , wherein the rocker arms 119 and 120 pivot about the shaft 121. In Fig. 10 also a boost pressure cell 124 is shown, in which the boost pressure acts through openings 125 on a membrane 126 and transmits the resulting displacement of this membrane against the force of a spring 127 to a transmission rod 128 which, with the interposition of a plate 129 on the Membrane 126 is supported. The to-and-fro displacement path of this transmission rod 128 is passed on to a rotating body 130 which again cooperates with rollers 131, a displacement of the transmission rod 128 in its axial direction causing the lever connected to the roller 131 to pivot. The roller 131 is non-rotatably connected to the pivot lever 119 via a hub 132 mounted on the shaft 121, so that a reciprocating movement of the rotary body 130 leads to a pivoting movement of the delivery quantity limit stop 104. Due to the rotationally secure coupling of the scanning elements 119 and 131, that pivoting of the delivery quantity limit stop 104 will occur which results in the larger pivoting path, one of the two rollers 122 and 131 then lifting off from the control surfaces assigned to them.

These relationships are shown more clearly in FIG. 11, the reference numerals of FIG. 10 being retained. The scanning rollers 122 and 123 are engaged with the rotating body 113 and, depending on the position of the rotating body 113, effect a corresponding adjustment of the pivoting levers 120 for the spray adjuster and the delivery rate limit stop 104. The storage of the delivery rate limit stop is dependent on a device which can be actuated at the start for release the path of the control rod is eccentrically adjustable and for this purpose an eccentric lever 133 is provided, which is pulled via an electromagnet 134 into a position 133 'corresponding to the start. In this position, the lever 133 rests on an expansion element 135, the core 136 of which is shifted as a function of the temperature, so that the adjustment path of the delivery limit stop for releasing the excess starting quantity can still be set as a function of the measured temperature. Due to the eccentric mounting of the shaft 121 the fulcrum of the angle lever 119 is shifted such that the roller 122 on the rotary body pivots the delivery limit stop 104 into a position which allows a greater delivery rate and thus a greater free path for the delivery rate adjustment member 100. After completion of the starting process, the electromagnet 134 is de-energized again, with 137 being an electronic delay element which keeps the electromagnet energized even after the switch 138 is opened until a predetermined delay time has expired. The pivot lever 133 then returns to its operating position due to the force of the spring 139 and the delivery quantity limiting element 104 is pivoted into the operating position, the position of the eccentric being adjustable in the operating position by a stop 140. The delivery quantity limiting element 104 is connected to a spring 141 which holds the rocker arm 119 and thus the roller 122 in contact with the rotating body 113. The rocker arm 120, which is connected to a spring 142, which holds the roller 123 of this rocker arm 120 in contact with the rotating body 113, is provided for the adjustment of the injection time as a function of the rotational speed. At the free end of this rocker arm 120, an adjustable stop 143 is provided, which interacts with a pressure oil-controlled servo element 144. By means of the pressure oil-controlled servo element 144, the displacement path of the rocker arm 120 is translated accordingly and the increased displacement path at the output of this servo element 144 is transmitted via a rack 145 to an eccentric 146, on which an actuating lever of the injection pump acts. The eccentric mounting of this actuating lever leads to an earlier or later start of the injection, depending on the displacement of the rack 145.

In FIG. 12, the delivery rate limit stop 104 is shown in the stop position on the delivery rate adjustment member 100. The delivery limit stop 104 has a stop ramp 147. By pivoting the delivery rate limit stop 104, the free path of the delivery rate adjustment member 100 is increased or decreased depending on the inclined surface of the ramp 147.

Claims (18)

1. Control apparatus for fuel injection pumps (26) of Diesel engines having individual injection pumps or individual unit-injectors (26), which controls the maximum quantity and timing of injection by means of cam surfaces (33, 43, 49; 118, 130) in accordance with operation parameters, characterized in that at least one cam surface (33, 43, 49; 118, 130) which limits the capacity of the pump at the highest optimum value assigned to the respective operating condition, is coaxially arranged on a common axle or shaft (114) at least together with one cam surface (34, 50; 117) setting the timing of injection.

2. Control apparatus according to claim 1, characterized in that the cam surfaces (33,43,49; 34, 50) are arranged on cam disks rotatable around the common axle and at least partially act on a common cam follower (31, 35) and, according to the control by the operation parameters to which they are assigned, engage this common cam follower.

3. Control apparatus according to claim 2, characterized in that the cam disks (33,43,49; 34, 50) controlled by various operation parameters and acting upon a common cam follower (31; 35) are pivoted on the common axle independently rotatable with respect to each other and come into engagement with the common cam follower (31; 35) independently of each other, only according to the control by the operation parameters to which they are assigned.

4. Control apparatus according to any of the claims 1, 2 or 3, characterized in that a stop (28), which limits the maximum stroke of the control rod (2) adjusting the capacity of the injection pump, is controlled by a cam follower (31) common to several cam surfaces (33, 43, 49), which is acted upon by a cam surface (33) connected with a governor (12, 13) and a cam surface (43) connected with a pressure sensing means (38) responsive to the pressure in the suction duct of the engine or to the atmospheric pressure, or a cam surface (49) connected with a temperature sensing means (77), responsive to an operating temperature such as the cooling water temperature, oil temperature and/or the temperature of the cylinder head, fuel temperature, or the ambient temperaturen, wherein all cam surfaces (33,43,49) act on the common cam follower (31) in a sense of reducing the maximum amount of fuel that can be injected.

5. Control apparatus according to any of the claims 2 to 4, characterized in that the cam disks (33, 34; 49, 50) controlled by the same operation parameter are rigidly connected with each other for rotation.

6. Control apparatus according to any of the claims 2 to 5, characterized in that toothed segments or pinions (32, 42, 48) are coaxially connected with the cam disks (33, 34, 43, 49, 50) and mesh with racks (18, 41, 47), which are adjustable by means responsive to the operation parameters.

7. Control apparatus according to any of the claims 4 to 6, characterized in that a cam disk (34) rigidly connected with the cam disk (33) that is coupled with the governor (12, 13) and a cam disk (50) rigidly connected with the cam disk (49) that is coupled with the temperature sensing means (77) cooperate with a cam follower (35), which controls the timing of injection.

8. Control apparatus according to claim 7, characterized in that a hydraulic amplifier (servo 36) is inserted into the mechanism of transmission between the cam follower (35) and the injection timing means.

9. Control apparatus according to any of the claims 4 to 8, characterized in that a separate governor (12, 13) is provided for controlling the cam surface (33, 34) coupled with the governor.

10. Control apparatus according to any of the claims 4 to 9, characterized in that the stop (28) limiting the maximum stroke of the control rod (2) is controlled by a pivoted lever (30), which is supported against the cam follower (31) and which is pivoted around an eccentric (69) whose rotation allows the amount of injected fuel to be increased at the start.

11. Control apparatus according to claim 1, characterized in that part of the cam surfaces (117, 118), at least, is formed by the generatrices of a solid of revolution (113) or segments of a solid of revolution, said solids of revolution or segments of solids of revolution being pivoted axially shiftable on the common axle (114), and in that the respective cam follower (122, 123) is designed as a cam follower lever which is pivoted on an exle (121) parallel to the axle of the solid of revolution and which cannot be displaced in the direction of its swivel axis.

12. Control apparatus according to claim 11, characterized in that the cam followers (122,123) are designed as rocking arm levers (119, 120) which have at least one arm forming the cam follower lever and whose other arm displaces the mechanism adjusting the operation parameter, and that at least one rocking arm lever (119) has several cam follower arms (122, 131), which coact with solids of revolution (113, 130) or segments controlled by various operation parameters.

13. Control apparatus according to claim 11 or 12, characterized in that two solids of revolution (117, 118) connected with each other are pivoted as to be displaced according to the number of revolutions, one (118) of which cooperates with a cam follower lever (122) controlling the stop (104) of the maximum capacity and the other (117) cooperates with a cam follower lever (120) controlling the timing of injection.

14. Control apparatus according to any of the claims 1, 11, 12 or 13, characterized in that a solid of revolution (118) that can be displaced according to the number of revolutions and a solid of revolution (130) that can be displaced by a pressure sensing means (124) are fixed on a common ax!e and that each solid of revolution cooperates with one cam follower arm (122, 131) of a rocking arm lever (119), whose other arm forms the stop (104) limiting the maximum capacity or actuates said stop.

15. Control apparatus according to any of the claims 1 or 11 to 14, characterized in that the rocking arm lever (119) having the arm which forms or actuates the stop (104) of the maximum capacity, is journalled on an eccentric, which may be rotated for increasing the starting quantity.

16. Control apparatus according to claim 15, characterized in that the extent of rotation of the eccentric is limited by a stop controlled by a temperature-sensitive means (135), which is responsive to the engine temperature.

17. Control apparatus according to any of the claims 11 to 16, characterized in that the lever arm forming the stop (104) of the maximum capacity has a ramp (147) which extends transversely to the swivel axis (121) of this lever arm and which forms the stop.

18. Control apparatus according to any of the claims 11 to 17, characterized in that the tip of the cam follower lever (119, 120) engaging the solid of revolution (113) is designed with a roller (122, 123) whose axle intersects the axle (121) on which the cam follower lever (119, 120) is journalled.

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