Abstract:
Embodiments relate to a valve arrangement for a fuel injection system, including a valve disc that has a valve opening. A deformable valve sheet that is movable in a movement direction is provided to open and close the valve opening, and a valve shaft of a movement-activation arrangement, provided to activate the movement of the valve sheet, is secured to the valve sheet. The embodiments also relate to a high-pressure pump which includes the valve arrangement.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of PCT International application No. PCT/EP2015/077813, filed Nov. 26, 2015, which claims priority to German patent application No. 10 2014 225 642.9, filed Dec. 12, 2014, each of which is hereby incorporated by reference herein. 
     
    
     FIELD OF INVENTION 
       [0002]    The invention relates to a valve arrangement for a fuel injection system of an internal combustion engine, and to a high-pressure pump for a fuel injection system, which high-pressure pump has such a valve arrangement. 
       BACKGROUND 
       [0003]    In the case of fuel injection systems of internal combustion engines, it is known to use high-pressure pumps which apply a high pressure to the fuel to be injected. The fuel that has had such a high pressure applied to it is then injected by way of injectors into combustion chambers of the internal combustion engine. The high pressure of the fuel has a positive effect on the emissions values of the internal combustion engine, in particular for example CO 2  emissions. It is therefore sought, in internal combustion engines which use gasoline as fuel, to achieve a pressure in the range from 200 bar-300 bar in the fuel, whereas in the case of diesel internal combustion engines, it is even the case that a pressure range of 2000 bar-3000 bar in the fuel is sought. 
         [0004]    For applying the desired pressure to the fuel, the high-pressure pump normally has one piston which increases and decreases the volume of a pressure chamber and, during the decrease in volume, compresses the fuel in order to realize the desired pressure of the fuel. At the pressure chamber there are arranged valves, on the one hand an inlet valve which admits the fuel into the pressure chamber before the fuel is compressed, and on the other hand an outlet valve which discharges the compressed fuel from the pressure chamber into a line which then conducts the fuel, for example via a common rail, to the injectors. 
         [0005]    Owing to the high pressures that can be achieved with the high-pressure pump, the closing elements of the valves are commonly of massive form, for example in the form of a ball valve or valve mushroom head, to name but two possible massive embodiments. 
         [0006]    Such valve elements are duly highly robust with regard to the prevailing pressures in the high-pressure pump, but react relatively slowly to the forces acting on them. 
         [0007]    Since high-pressure pumps commonly operate in the range of several thousand strokes per minute, it is however desirable, in particular, for the admission of the fuel into the pressure chamber to provide relatively fast-switching valves which can open and close quickly. 
         [0008]    It is therefore known, for example, to use not ball valves or massive mushroom head closing elements but filigree valve lamellae which are deformable and which can open and close the respective valve by way of their deformation. Such an arrangement is described, for example, in EP 1 724 467 A1. 
         [0009]    The valve lamella described in EP 1 724 467 A1 opens and closes owing to pressure differences in the fuel in a pressure chamber of the high-pressure pump. If the pressure in the pressure chamber is higher than that in the suction region arranged upstream of the pressure chamber, the valve lamella closes, whereas the valve lamella opens if the pressure in the suction region is higher than that in the pressure chamber. To hold the valve lamella open in targeted fashion, the valve lamella is, by a valve shank, forced into the open position even counter to a higher pressure in the pressure chamber than in the suction region, in order that the pump power of the high-pressure pump can thereby be set. If it is not sought to manually influence the pump power, the valve shank retracts and is not in contact with the valve lamella, such that the valve lamella can close owing to the pressure prevailing in the pressure chamber. 
         [0010]    All known arrangements have the disadvantage that the operation thereof gives rise to a high level of noise generation during switching. 
       SUMMARY 
       [0011]    It is therefore an object of the invention to propose a valve arrangement and a high-pressure pump which overcome the problem. 
         [0012]    A valve arrangement for a fuel injection system of an internal combustion engine has at least one valve opening arranged in a valve disk, wherein the valve opening fluidly connects to or is in fluid communication with one another a first valve disk side and a second valve disk side situated opposite the first valve disk side, which valve disk sides are separated from one another by the valve disk. Furthermore, the valve arrangement has a deformable valve lamella which is movable along a movement direction and which serves for opening and closing the valve opening, which valve lamella may, in order to close the valve opening, be brought into contact with a valve disk surface on the first valve disk side. Furthermore, a movement activation arrangement for activating a movement of the valve lamella along the movement direction is provided, which movement activation arrangement has a valve shank which is fixed to the valve lamella. 
         [0013]    This has the advantage that the length of the movement of the valve shank is delimited by the valve lamella when the latter comes into contact with the valve disk surface. A situation is thus prevented in which, during operation, the valve shank strikes for example a region of the valve arrangement, causing an activation of the movement of the valve shank. This leads to reduced noise generation by the valve arrangement during operation. Furthermore, it is also possible in this way for protective coatings or cumbersome machining of surfaces of elements of the valve arrangement that otherwise strike one another to be avoided. 
         [0014]    Furthermore, the valve arrangement has the advantage that there is no longer a need for additional holding measures for holding the valve lamella in position, such as for example a stopper for preventing the valve lamella from being drawn into the center of the pressure chamber, or a fastening of the valve lamella directly to the valve disk. 
         [0015]    It is particularly advantageously the case that the valve shank extends through the valve opening in order that the shank may be connected particularly easily to the valve lamella. It is furthermore advantageous if the valve shank is fixed in the central region of the valve lamella in order to thereby permit a symmetrical introduction of force from the valve shank into the valve lamella. 
         [0016]    The valve disk has multiple openings, wherein the valve lamella is designed such that, in the closed position, the valve lamella may close all of the valve openings simultaneously. The valve lamella may in this case be of circular or angular form, wherein it is advantageous for the valve lamella to close all of the valve openings when the lamella bears against the valve disk surface. It is also possible for the valve lamella to be formed with recesses in order to make the lamella even more deformable, wherein then, for the valve openings, there should be provided corresponding valve lamella regions which may then close the valve openings. 
         [0017]    The valve shank is fixed to the valve lamella in one embodiment by a screw connection, wherein a screw element bears against the valve lamella, in particular on a first valve lamella side facing away from the second valve disk side, and extends through the valve lamella. Screw connections of elements may, with a sufficient resistance, oppose the high load that acts on the connection owing to the high pressure in the pressure chamber. It is additionally advantageous if the screw element bears against the valve lamella, for example has a screw head which bears against the valve lamella, and thus supports the valve lamella during the movement thereof. In this way, the filigree valve lamella may altogether likewise be made advantageously more robust. 
         [0018]    It is additionally or alternatively also possible, in an embodiment, for the valve shank to be fixed by a welded connection to the valve lamella. Welded connections also offer a high level of stability and may therefore advantageously contribute to the durability of the connection. It is particularly advantageous for a welded connection of this type to be arranged such that it may preload the valve lamella counter to a force acting on the valve lamella from the direction of the pressure chamber, that is to say may exert a pressure on the valve lamella in the direction of the pressure chamber. In this way, the open position of the valve lamella during the delivery stroke of the high-pressure pump is additionally assisted. 
         [0019]    In addition or alternatively, on the valve lamella, there is arranged a sleeve-shaped receiving element which is in engagement with the valve shank. In this way, an advantageous form fit is provided between the valve lamella and the valve shank, which form fit may likewise contribute to durability of the connection. 
         [0020]    For example, in one embodiment the receiving element may in this case be crimped to the valve shank in order to realize the form fit. The bead formed here ensures a particularly advantageous sealing action of the connection. 
         [0021]    In another embodiment, the receiving element is a circlip which is in engagement with the valve shank. 
         [0022]    As a further alternative, in another embodiment the receiving element is formed by a clip element which engages behind the valve lamella and thus ensures a secure connection between valve lamella and the valve shank. 
         [0023]    In another embodiment, the receiving element is formed by a valve lamella opening which is arranged in the valve lamella and which has opening walls which are in engagement with the valve shank. This embodiment is particularly easy to produce. 
         [0024]    In another embodiment, however, alternatively the valve lamella is formed integrally with an end of the valve shank, facing toward the first valve disk, which has the advantage that, in this way, it is possible to eliminate potential breaking points of a connection. 
         [0025]    In another embodiment, however, the valve lamella has an engagement shank which engages through the valve opening into a recess of the valve shank and may thus produce a robust connection by a form fit with the end of the valve shank. It is particularly advantageous if the engagement shank also engages through the valve lamella and is additionally advantageously fastened by welded connections to the valve lamella. Here, it is particularly advantageous for not just one welded connection to the valve lamella be provided but for in each case one welded connection on two valve lamella surfaces to connect the valve lamella to the engagement shank. This ensures a particularly reliable and firm connection of engagement shank, valve lamella and thus also valve shank. 
         [0026]    The valve lamella is in the form of a spring element whose spring force is directed counter to a force which acts on the valve lamella from a first valve lamella side. For example, here, the valve lamella may be in the form of a disk spring or leaf spring. It is also possible for the valve lamella to be a coil spring or conical spring which has closing elements which may close the at least one valve opening. 
         [0027]    Here, it is advantageously the case that the spring force of the valve lamella is greater than a predetermined force which corresponds to a maximum hydraulic force on the first valve lamella side during the operation of the valve arrangement. This means that, when the high-pressure pump pumps fuel, the valve lamella opposes a force generated by the pressurized fuel with enough resistance to remain in the open position. Here, the predetermined force may correspond to a force which is imparted by the fuel when the fuel has been compressed to the maximum extent by the pump piston. In this way, it is advantageously possible, in the event of a breakage of the valve shank, to prevent the valve lamella from closing the valve opening, which would result in the high-pressure pump no longer being capable of imparting a full delivery action. In this embodiment, it is particularly advantageous if the valve shank is provided for moving the valve lamella into the closed position; that is to say if, without activation of the valve lamella, the valve arrangement is open. 
         [0028]    The valve lamella is fixed at least in sections to the valve disk. In this way, a valve lamella in the form of a spring element is supported particularly easily on the valve disk. The fixing of the valve lamella to the valve disk may be realized, for example, by welding and/or vulcanizing and/or adhesive bonding or similar connecting methods which may withstand the high pressures in the region of the valve lamella. 
         [0029]    In an advantageous refinement, the movement activation arrangement has a magnetic actuator with a static pole piece and an armature which is connected to the valve shank and serves as a positioning element. Here, the valve shank is connected to the armature, in particular formed integrally with the armature. When energized, the magnetic actuator adjusts the armature and the valve shank fastened thereto along the movement direction of the valve lamella, whereby at the same time the valve lamella is moved from the open position into the closed position and vice versa. Here, the arrangement may be such that the valve lamella is closed when energized, or may be such that the valve lamella is opened when energized. The movement activation arrangement is configured such that, in all operating positions of the valve arrangement, the armature and the pole piece are arranged so as to be spaced apart from one another, which has the advantage that, during switching of the valve arrangement, contact between the armature and pole piece no longer occurs, and thus the noise emissions of the valve arrangement is be considerably reduced. 
         [0030]    Here, a spring element is provided which holds the armature and the pole piece so as to be spaced apart from one another. The spring element is particularly advantageously formed by the valve lamella. In a refinement, specifically in a refinement of the valve arrangement in which the latter is open when de-energized, the valve lamella, by its spring force, holds the armature in the rest position, so as to be spaced apart to a maximum extent from the pole piece. 
         [0031]    A high-pressure pump for a fuel injection system of an internal combustion engine has a pressure chamber for applying high pressure to fuel, and has an inlet valve for the admission of the fuel into the pressure chamber, wherein the inlet valve is formed by a valve arrangement as described above. Here, the pressure chamber is formed on the first valve disk side. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0032]    Refinements of the invention will be discussed in more detail below on the basis of the appended drawings, in which: 
           [0033]      FIG. 1  is a schematic illustration of a fuel injection system of an internal combustion engine having a high-pressure pump and having valve arrangements arranged thereon; 
           [0034]      FIG. 2  shows a longitudinal section of the high-pressure pump and the valve arrangements arranged thereon from  FIG. 1 ; 
           [0035]      FIG. 3  is a first schematic illustration, in longitudinal sectional view, of the high-pressure pump from  FIG. 2  with a valve arrangement fully open; 
           [0036]      FIG. 4  is a second schematic illustration, in longitudinal sectional view, of the high-pressure pump from  FIG. 2  with a valve arrangement fully open; 
           [0037]      FIG. 5  is a third schematic illustration, in longitudinal sectional view, of the high-pressure pump from  FIG. 2  with a valve arrangement fully closed; 
           [0038]      FIG. 6  is a first detailed longitudinal sectional illustration of the valve arrangement from  FIGS. 3-5 ; 
           [0039]      FIG. 7  is a second detailed longitudinal sectional illustration of the valve arrangement from  FIGS. 3-5 ; 
           [0040]      FIG. 8  is a schematic illustration of the connection of a valve lamella of the valve arrangement from  FIG. 6  and  FIG. 7  to a valve shank of the valve arrangement, according to a first example embodiment; 
           [0041]      FIG. 9  is a schematic illustration of the connection of the valve lamella of the valve arrangement from  FIG. 6  and  FIG. 7  to the valve shank of the valve arrangement, according to a second example embodiment; 
           [0042]      FIG. 10  is a schematic illustration of the connection of the valve lamella of the valve arrangement from  FIG. 6  and  FIG. 7  to the valve shank of the valve arrangement according to a third example embodiment; 
           [0043]      FIG. 11  is a schematic illustration of the connection of the valve lamella of the valve arrangement from  FIG. 6  and  FIG. 7  to the valve shank of the valve arrangement according to a fourth example embodiment; 
           [0044]      FIG. 12  is a schematic illustration of the connection of the valve lamella of the valve arrangement from  FIG. 6  and  FIG. 7  to the valve shank of the valve arrangement according to a fifth example embodiment; 
           [0045]      FIG. 13  is a schematic illustration of the connection of the valve lamella of the valve arrangement from  FIG. 6  and  FIG. 7  to the valve shank of the valve arrangement according to a sixth example embodiment; 
           [0046]      FIG. 14  is a schematic illustration of the connection of the valve lamella of the valve arrangement from  FIG. 6  and  FIG. 7  to the valve shank of the valve arrangement according to a seventh example embodiment; 
           [0047]      FIG. 15  is a schematic illustration of the connection of the valve lamella of the valve arrangement from  FIG. 6  and  FIG. 7  to the valve shank of the valve arrangement according to an eighth example embodiment; 
           [0048]      FIG. 16  is a schematic illustration of the connection of the valve lamella of the valve arrangement from  FIG. 6  and  FIG. 7  to the valve shank of the valve arrangement according to a ninth example embodiment; 
           [0049]      FIG. 17  is a schematic illustration of the connection of the valve lamella of the valve arrangement from  FIG. 6  and  FIG. 7  to the valve shank of the valve arrangement according to a tenth example embodiment; 
           [0050]      FIG. 18  is a schematic illustration of the connection of the valve lamella of the valve arrangement from  FIG. 6  and  FIG. 7  to the valve shank of the valve arrangement according to an eleventh example embodiment; and 
           [0051]      FIG. 19  is a schematic illustration of the connection of the valve lamella of the valve arrangement from  FIG. 6  and  FIG. 7  to the valve shank of the valve arrangement according to a twelfth example embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0052]      FIG. 1  is a schematic illustration of a fuel injection system  10  of an internal combustion engine, which fuel injection system delivers a fuel  12  from a tank  14  via a predelivery pump  16 , a high-pressure pump  18  and a fuel high-pressure accumulator  20  to injectors  22  which then inject the fuel  12  into combustion chambers of the internal combustion engine. 
         [0053]    The fuel  12  is introduced into the high-pressure pump  18  via a valve arrangement  24 , and is discharged from the high-pressure pump  18  under pressure via a further valve  26 . 
         [0054]      FIG. 2  shows a longitudinal section through the high-pressure pump  18  with the valve arrangement  24  as inlet valve  28  and with the valve  26  as outlet valve  30 , which valve arrangement and valve are arranged at a pressure chamber  32  of the high-pressure pump  18 . During the operation of the high-pressure pump  18 , a piston  34 , which performs a translational movement, periodically varies the volume of the pressure chamber  32 . Here, the piston  34  is driven by a camshaft  36  which, in the present example embodiment, is in operative contact with the piston  34  via a tappet  38 . 
         [0055]      FIG. 3  to  FIG. 5  schematically show different operating states of the piston  34  and of the inlet valve  28  in longitudinal sectional view through the high-pressure pump  18  during the operation of the high-pressure pump  18 . 
         [0056]    Here, in the present embodiment, the outlet valve  30  is a simple check valve  40  which opens passively owing to a pressure prevailing in the pressure chamber  32  and which automatically closes again in the absence of the pressure. 
         [0057]    In the present embodiment, the inlet valve  28  is an active magnetic valve  42  which has a magnetic actuator  44  with a static pole piece  46  and with a movable armature  48  as a positioning element  50 . To the armature  48  there is fastened a valve shank  52  which engages through a valve opening  54  in a valve disk  55  and to which there is fastened a valve lamella  56  which, when moved in the direction of the pole piece  46 , may be placed in contact with a valve disk surface  58  on a first valve disk side  60  of the valve disk  55 , in order to thereby close the valve opening  54 . In the present embodiment, the inlet valve  28  is an inlet valve  28  which is open when de-energized, that is to say, when the magnetic valve  42  is not energized, the pole piece  46  and the armature  48  are, owing to a spring  62 , arranged with a maximum spacing  64  to one another, such that the valve lamella  56  is situated in an open position. At the same time, the piston  34  is on the path toward the bottom dead center of the piston, as indicated by the arrow P 1 . Owing to the movement of the piston  34  and the open position of the valve lamella  56 , fuel  12  flows, as indicated by the arrows P 2 , into the pressure chamber  32  of the high-pressure pump  18 . The outlet valve  30  is in its closed position. 
         [0058]      FIG. 4  schematically illustrates, in longitudinal sectional view, how the piston  34  moves toward the top dead center thereof. The valve lamella  56  remains in the open position owing to the spring force of the compression spring  62 , because the pressure built up in the pressure chamber  32  by the piston  34  is not yet sufficient to overcome the spring force of the compression spring  62  and close the valve lamella  56 . The outlet valve  30 , too, is still situated in the closed position thereof. Owing to the valve lamella  56  being in the open position, fuel  12  flows out of the pressure chamber  32  again through the inlet valve  28 . 
         [0059]    In  FIG. 5 , the piston  34  is situated a short distance before the top dead center thereof, and the pressure that has been built up in the pressure chamber  32  by the movement of the piston  34  is sufficient to close the valve lamella  56 . At the same time, the pressure is also sufficient to open the outlet valve  30 . 
         [0060]    The spring force of the compression spring  62  prevents the high-pressure pump  18  from operating with full delivery action, that is to say all of the fuel  12  that has flowed into the pressure chamber  32  is, as a result of immediate closure of the valve lamella  56 , charged with pressure, and thus all of the elements situated downstream of the pressure chamber  32  are subjected to load. 
         [0061]    The valve lamella  56  is designed to be so thin that the lamella is deformable. Furthermore, for the closure of the valve opening  54 , the valve lamella moves along a movement direction  57  which is oriented along a longitudinal axis of the valve shank  52 . 
         [0062]      FIG. 6  and  FIG. 7  show a longitudinal section through the valve arrangement  24 , in the form of an inlet valve  28 , in two different embodiments. 
         [0063]    Here,  FIG. 6  shows an arrangement which has the compression spring  62 , whereas, in  FIG. 7 , the compression spring  62  has been omitted, because the valve lamella  56  itself forms a spring element  70 . 
         [0064]    The elements of the magnetic valve  42 , specifically the pole piece  46  and the armature  48 , and the valve shank  52  together form a movement activation arrangement  72  which may actively move the valve lamella  56 . If the valve arrangement  24  is an open valve, the movement activation arrangement  72  moves the valve lamella  56  into the closed position when energized. However, if the valve arrangement  24  is designed to be closed when de-energized, the movement activation arrangement  72 , when energized, moves the valve lamella  56  into the open position. For the separation of the pressure chamber  32  from a suction line  74 , the valve disk  55  is provided, which valve disk separates the first valve disk side  60  on the side of the pressure chamber  32  from a second valve disk side  76  on the side of the suction line  74 . The two valve disk sides  60 ,  76  are fluidly connected to or in fluid communication with one another by the valve opening  54 . To shut off the fluidic connection, the valve lamella  56  is provided, which is deformable such that the lamella may bear closely against the valve disk surface on the first valve disk side  60  in order to thereby sealingly close off the valve opening  54 . 
         [0065]    By virtue of the fact that the valve shank  52  and the valve lamella  56  are firmly fastened to one another, it may be achieved that the pole piece  56  and the armature  48 , which is connected to the valve shank  52 , are spaced apart from one another in all operating positions of the valve arrangement  24 . Specifically, if the valve shank  52  is so short that the armature  48  fastened thereto does not strike the pole piece  46  when the valve opening  54  is fully closed by the valve lamella  56 , a permanent spacing  64  between the pole piece  46  and the armature  48  is realized. In this way, a loud impacting noise during the operation of the valve arrangement  24  may be prevented. 
         [0066]      FIG. 6  and  FIG. 7  show embodiments in which the valve arrangement is designed as a valve which is open when de-energized. Here, in  FIG. 6 , when the valve arrangement  24  is in the rest position, the compression spring  62  holds the armature  48  with a maximum spacing  64  to the pole piece  46 , and thus holds the valve lamella  56  in the open position. 
         [0067]    By contrast, no compression spring  62  is provided in  FIG. 7 , it rather being the case that the valve lamella  56  itself is in the form of a spring element  70 , the spring force of which acts counter to a force acting on the valve lamella  56  from the pressure chamber  32 , and the valve lamella thus holds itself open. In this way, the compression spring  62  between armature  48  and pole piece  46  is omitted. 
         [0068]    If the valve lamella  56  was not connected to the valve shank  52 , and the valve lamella  56  was not in the form of a spring element  70 , this relieving of the downstream elements of load would function only until the valve shank  52  experiences a malfunction, for example a breakage. As a result of a breakage, the valve shank  52 , because the valve shank is not connected to the valve lamella  56 , would no longer be able to hold the valve lamella in the open position, and the valve lamella  56  would immediately close as soon as only a low pressure is built up in the pressure chamber  32 . As a result, the high-pressure pump  18  would impart a full delivery action. This normally makes it necessary to provide a safety valve which relieves the downstream elements of load in the event of the high-pressure pump  18  imparting a full delivery action. 
         [0069]    Provision is, however, now made for the valve shank  52  to be connected to the valve lamella  56 , and for the valve lamella  56  to be formed as a spring element  70 . Now, if the valve shank  52  breaks, the valve arrangement  24  remains permanently in the open state, such that it is not possible for an excessive pressure to act on the following elements downstream of the pressure chamber  32 . This is because the high-pressure pump  18  no longer imparts a full delivery action, it rather being the case that the valve lamella  56  remains permanently in the open position, such that pressurized fuel  12  may flow back again to the suction line  74  and does not exert load on those elements of the fuel injection system  10  which are situated downstream of the high-pressure pump  18 . 
         [0070]    It is thus possible to dispense with an additional safety valve which relieves the system of load when the high-pressure pump  18  imparts a full delivery action. 
         [0071]    An additional advantage is that, when the energization of the valve arrangement  24  has ended, the spring force of the spring element  70  has the effect that the valve shank  52  no longer strikes the valve disk  55  at such a high speed, because the impacting speed and thus the energy is lower. This also contributes to a reduction of the generation of noise by the valve arrangement  24 . 
         [0072]    To ensure the above-described functionality of the valve arrangement  24  even in the event of malfunctions of the valve shank  52 , it is advantageous if, here, the spring force of the valve lamella  56  is configured so as to be greater than the maximum hydraulic force exerted on the valve lamella  56  by the pressurized fuel  12 . As a result, when not moved by the movement activation arrangement  72 , the valve lamella  56  remains permanently in the open position, such that it is not possible for the high-pressure pump  18  to impart a full delivery action. In this way, it is, for example, also possible to dispense with a further safety valve, because even in the event of a breakage of the valve shank  52 , the valve lamella  56  remains in the open position. 
         [0073]    The valve lamella  56  may, for stabilization, also be advantageously connected at least in sections at a circumferential edge  78  to the valve disk  55 . 
         [0074]      FIG. 8  to  FIG. 18  schematically show different embodiments for fixing the valve shank  52  to the valve lamella  56 . In all embodiments, the valve shank  52  is advantageously connected to the valve lamella  56  such that an end  79 , facing toward the first valve disk side  60  of the valve shank  52 , is arranged in a central region  81  of the valve lamella  56 . 
         [0075]    Here,  FIG. 8  shows a screw connection  80 , in which a screw element  82  engages through the valve lamella  56  proceeding from a first valve lamella side  84 , facing away from the second valve disk side  76 , and bears against the valve lamella  56 . The screw element  82  is then screwed into the valve shank  52 . 
         [0076]      FIG. 9  shows an embodiment in which the valve shank  52  is connected to the valve lamella  56  by a welded connection  86 . Here, a weld seam  88  of the welded connection  86  is arranged so as to be situated on a second valve lamella side  90  situated opposite the first valve lamella side  84 , so as to exert a pressure on the valve lamella  56  such that the valve openings  54 , which would be closed off by the valve lamella  56 , remain open. By virtue of the fact that the end  79  of the valve shank  52  is arranged in the central region  81  of the valve lamella  56 , and by virtue of the fact that the weld seam  88  exerts a pressure on the valve lamella  56 , the valve lamella  56  is preloaded and acts as a spring element  70  counter to a force acting on the valve lamella  56  from the first valve lamella side  84 . 
         [0077]      FIG. 10  to  FIG. 16  schematically show embodiments with sleeve-shaped receiving elements  92  which are used to connect the valve shank  52  to the valve lamella  56 . 
         [0078]    Here, in  FIG. 10 , the sleeve-shaped receiving element  92  is formed by a sleeve  94  which is fastened to the first valve lamella side  84 . Here,  FIG. 11  shows a bead  96  which is arranged as a sleeve-shaped receiving element  92  on the valve lamella  56  and at which the valve shank  52  is crimped, and thus connected by a form fit, to the receiving element  92 . As shown in  FIG. 12 , a valve lamella opening  98  is provided in the valve lamella  56  in the central region  81 , wherein the valve shank  52  is then in engagement with the opening walls  100  of the valve lamella opening  98 .  FIG. 13  shows an embodiment in which a punched-out or otherwise outwardly bent portion  102  is formed as the sleeve-shaped receiving element  92  on the valve lamella  56 . In  FIG. 14 , as the sleeve-shaped receiving element  92 , a circlip  104  is in engagement with the valve shank  52 .  FIG. 15  shows an arrangement in which an additional clip element  106  is the sleeve-shaped receiving element  92 , which clip element is clipped into a valve lamella opening  98  of the valve lamella  56  in the central region  81 , and into which clip element the valve shank  52  is inserted.  FIG. 16  also shows a sleeve-shaped receiving element  92  which is welded to the valve lamella  56 , wherein here, however, the valve disk  55  is of angled form, such that a spring force of the deformable valve lamella  56  is automatically realized without the valve lamella  56  having to be preloaded.  FIG. 17  and  FIG. 18  show valve lamellae  56  which are formed integrally with the valve shank  52 . In  FIG. 19 , the valve lamella  56  has an engagement shank  108  which is welded to the valve lamella  56  and which engages through the valve opening  54  into a recess  110  of the valve shank  52 . It is advantageous for the engagement shank  108  to also engage through the valve lamella  56  and to be fastened to the valve lamella  56  both at a first valve lamella surface  112  and at a second valve lamella surface  114 . 
         [0079]    By way of the valve arrangement  24  described above, the component costs in some embodiments may be lowered because the compression spring  62  is omitted and, for example, it is also possible for a holder for the valve lamella  56  to be omitted. It is thus the case, in general, that the risk of failure of the high-pressure pump  18  is lowered. Furthermore, it is also possible for the machining costs to be lowered because, for example, owing to the permanent spacing  64  of the pole piece  46  and armature  48 , the two elements no longer require a chromium coating and ground portions. The generation of noise by the valve arrangement  24  during operation may also be considerably reduced overall. Since it is possible to realize lower power consumption during operation, it is also possible for the switching time to be optimized, and also to realize an optimization of the calibration on the vehicle. Altogether, the robustness of the valve arrangement  24  and thus also of the high-pressure pump  18  are increased. It is also possible for hydraulic pulsations in the low-pressure region to be reduced, and a safety valve that is normally provided may be omitted. It is also achieved that the power consumption is reduced, because the valve arrangement  24  no longer has to be switched to the full extent because, through the use of the valve lamella  56  in the embodiment as a spring element  70 , the stroke is greatly reduced. In this way, it may be achieved that the vehicle calibration no longer has to be calibrated to that point in the current profile at which the armature  48  strikes the pole piece  46 , but rather merely has to be calibrated to the point at which the valve lamella  56  is situated fully in the closed position thereof. Since the chromium layer on the pole piece  46  and armature  48  may be omitted, it is also the case that wear no longer occurs here. Furthermore, failures at the compression spring  62 , or at a holding element that has acted as a stopper for the previously loose valve lamella  56 , may no longer occur. The safety valve may be omitted entirely, or no longer has to be designed for robustness, because the safety valve only has to be designed for special cases such as, for example, the “hot soak” of the high-pressure pump  18 . The pulsations in the low-pressure region are significantly reduced because the pole piece  46  and the armature  48  now no longer strike one another during switching, and thus the medium situated in between no longer has to be displaced to zero. 
         [0080]    During the manufacturing process, it is possible for the valve shank  52  to be installed into a complete valve arrangement element in advance, wherein then, the valve lamella  56  together with the installed valve shank  52  is pushed through the valve disk  55 . The arrangement may then be inserted as an entire element into the pump housing of the high-pressure pump  18 . 
         [0081]    It is furthermore also possible for the valve disk  55  to be fixedly incorporated as a constituent part of the housing, which is more robust with respect to high combustion chamber pressures. Here, it is then the case that the valve lamella  56  with the valve shank  52  installed thereon is inserted from the high-pressure side, that is to say from the direction of the pressure chamber  32 , and the other elements of the valve arrangement  24  are inserted from the other side, specifically from the direction of the suction line  74 . 
         [0082]    As a third possibility, it is also possible for the valve disk  55  to be inserted, with a preassembled assembly composed of valve shank  52  and valve lamella  56 , into the structural space, for a supporting ring to then be pushed in, and for such supporting ring to be fixed by a weld seam. 
         [0083]    It is particularly advantageous if, in the de-energized state, the valve lamella  56  is no longer planar but has a concave internal stress, that is to say a spring force. The internal stress is advantageously of such a magnitude that the backflowing medium in the pressure phase cannot push the valve lamella  56  back. The preload makes it possible, in a partial delivery situation, for a flow cross section for backflowing medium to be kept free. 
         [0084]    Embodiments have been described herein in an illustrative manner, and it is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than of limitation. Obviously, many modifications and variations of the invention are possible in light of the above teachings. The description above is merely exemplary in nature and, thus, variations may be made thereto without departing from the spirit and scope of the invention as defined in the appended claims.