Abstract:
A device for the media-tight connection of two high-pressure components includes: a sealing cone having a central channel through which a medium under high pressure may flow, which sealing cone is pressed into a seal seat in order to seal against the medium which is under high pressure, and a high-pressure filter is accommodated in the channel in the sealing cone.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a device for the media-tight connection of two high-pressure components. 
         [0003]    2. Description of the Related Art 
         [0004]    High-pressure components are used, for example, in auto-igniting internal combustion engines in which fuel under high pressure is injected into the individual combustion chambers of the internal combustion engine. For this purpose, the so-called “common rail technology” is used, in which fuel under high pressure is stored at essentially constant pressure in a high pressure store. The individual combustion chambers of the internal combustion engines are supplied with fuel via the high pressure store. 
         [0005]    Testing facilities containing the corresponding high-pressure components are also used to test the individual components. 
         [0006]    Since the individual high-pressure components used are sensitive to contaminants, high-pressure filters are generally installed in adapters in the inlet lines to the high-pressure components. The high-pressure filters remove particles contained in the liquid under high pressure, which flows through the high-pressure components, or contained in the liquid which is present in the high-pressure components. In addition to the use of high-pressure filters in adapters which are inserted into the inlet lines, filters are also sometimes mounted directly in high-pressure components, for example in a pressure control valve. 
         [0007]    To ensure media seal-tightness at pressures of greater than 250 MPa, a grip edge is usually integrated into a high-pressure component which, during assembly of the high-pressure components, cuts into a surface of the mating part to which the high-pressure component is connected. This results in a groove in the surface of the mating part, which is generally a second high-pressure component. In addition, the grip edge also deforms. The surface of the second high-pressure component is damaged due to the cutting by the grip edge. If it is necessary to remove or replace one of the high-pressure components due to wear, soiling, repairs, or the like, each additional time the first high-pressure component is fastened to the second high-pressure component, the groove resulting from the cutting by the grip edge is further deepened, and the second high-pressure component is further damaged. After a limited number of assemblies and disassemblies, it is no longer possible to ensure an adequate seal, and the high-pressure component having the smooth surface, generally the high pressure store, must be replaced. 
         [0008]    In particular when the high pressure store is used for testing purposes in a laboratory, individual components which are tested are regularly exchanged. This quickly results in damage to the high pressure store, thus necessitating replacement. In addition, components such as pressure control valves, which have an integrated filter, must be regularly removed to clean the filter. This also results in damage to the high pressure store. Another disadvantage of the required frequent removal of the pressure control valves is that additional components are required, which increases the costs for the testing. 
         [0009]    The use of high-pressure filters which are inserted into adapters mounted in the inlet lines requires additional sealing points. In particular when the high-pressure components are used for testing, rigid lines, which are necessary for the use of high-pressure filters installed in adapters, are impractical due to the frequent changing of test pieces, in particular the injection pumps. 
       BRIEF SUMMARY OF THE INVENTION 
       [0010]    A device according to the present invention for the media-tight connection of two high-pressure components includes a sealing cone having a central channel through which a medium under high pressure may flow, the sealing cone being pressed into a seal seat in order to seal against the medium which is under high pressure, and a high-pressure filter being accommodated in the channel in the sealing cone. 
         [0011]    The use of a sealing cone which is mounted in the area of the connecting point of two high-pressure components has the advantage that with the aid of the sealing cone, on the one hand a media-tight connection is achieved, and on the other hand, particles contained in the liquid flowing through the sealing cone are directly removed due to the high-pressure filter which is integrated into the sealing cone. Another advantage of using a sealing cone is that it may be easily removed during disassembly of the high-pressure components, for example in order to clean the high-pressure filter, or alternatively, to replace the sealing cone when the high-pressure filter becomes soiled. As the result of using the sealing cone, which is not provided with a grip edge, the surface of the second high-pressure component is not damaged, and the sealing cone may be replaced as often as desired. 
         [0012]    The high-pressure filter is fastened in the sealing cone by force-fitting, for example. Alternatively, it is possible to weld the high-pressure filter into the sealing cone, in particular when a high-pressure filter made of metal is used. In addition, the high-pressure filter may be screwed in or fastened in the sealing cone in any other desired manner. 
         [0013]    In a first specific embodiment, the sealing cone is designed as a taper, and has an opening angle that is 0.5° to 5°, preferably 1° to 3°, for example 2°, smaller than the opening angle of the seal seat. In one particularly preferred specific embodiment, the sealing cone has a taper of 58°, and the seal seat correspondingly has an angle of 60°. Alternatively, for example, an angle of 43° for the sealing cone and an angle of 45° for the seal seat are also preferred. 
         [0014]    In one alternative, particularly preferred specific embodiment, the sealing cone has a convex shape. To achieve a tight fit, it is preferred that the radius of the convex surface be larger than the height of the sealing cone. In general, only a slight convex curvature is sufficient. As a result of the convex shape of the sealing cone, a more uniform stress on the seal seat is achieved, since a uniform contact against the seal seat is ensured due to the convex shape. On account of the convex shape, larger tolerances may be compensated for than with a conical sealing cone. 
         [0015]    To connect the two high-pressure components to one another it is possible, for example, to form a thread on each of the high-pressure components and to screw the components together, in this case the sealing cone being inserted into a recess between the high-pressure components. Alternatively, it is possible, for example, to provide an external thread on the first high-pressure component, and to provide an enlargement on the second high-pressure component, the second component being enclosed by a union nut, and for the connection, the union nut resting on the enlargement of the second high-pressure component and being screwed onto the first high-pressure component via the thread in such a way that a contact force necessary for the sealing is applied to the sealing cone, which is positioned at the connecting point of the first high-pressure component and the second high-pressure component. For the assembly, it is also possible that the enlargement is not provided directly on the second high-pressure component, but instead is an end face of a pressure ring which is screwed onto the first high-pressure component. 
         [0016]    If the sealing cone having the integrated high-pressure filter is used as a wear and tear part, it is possible, for example, for the sealing cone to have a side with a conical shape, as well as a flat surface. The conical side of the sealing cone is placed into a seal seat. For example, a grip edge of the first or the second high-pressure component acts on the smooth surface of the sealing cone. Replacement of the sealing cone does not further deepen the groove which results from the action by the grip edge, so that a tight connection between the first high-pressure component and the second high-pressure component is always achieved by using a new sealing cone in each case. 
         [0017]    In an alternative specific embodiment, the sealing cone is designed as a double cone. In this case, a conical seal seat is provided in the first high-pressure component as well as in the second high-pressure component, and the sealing cone is inserted into the seal seat in each case. The media-tight connection is achieved by force-fitting the sealing cone into the particular seal seat. 
         [0018]    To connect the first high-pressure component and the second high-pressure component, a first taper of the double cone is force-fitted into a first seal seat on the first high-pressure component, and a second taper of the double cone is force-fitted into a second seal seat on the second high-pressure component. The first high-pressure component and the second high-pressure component may once again be connected, for example, by screwing the two components together, either directly or with the aid of a union nut. 
         [0019]    Metallic materials are particularly suited as a material for producing the sealing cone. Alternatively, however, it is also possible to form the seal seat from a ceramic material, for example. The material used must be stable against the pressure which acts on the sealing cone, and must also withstand a compressive force resulting from pressing the sealing cone against the particular seal seat. 
         [0020]    In one particularly preferred specific embodiment, the first high-pressure component is a high pressure store, and the second high-pressure component is a supply line to the high pressure store or an inlet to a pressure control valve that is connected to the high pressure store. The high pressure store may be a high pressure store in an auto-igniting internal combustion engine in a vehicle, or may be a high pressure store for a testing device for injection nozzles or other high-pressure components. 
     
    
     
       DETAILED DESCRIPTION OF THE DRAWINGS 
         [0021]      FIG. 1  shows a device for testing high-pressure components. 
           [0022]      FIG. 2  shows a sealing cone according to the present invention in a first specific embodiment. 
           [0023]      FIG. 3  shows a sealing cone according to the present invention in a second specific embodiment. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0024]      FIG. 1  illustrates a device for testing high-pressure components. A device for testing high-pressure components includes a housing  1  in which a high pressure store is accommodated. The high pressure store accommodated in housing  1  is connected to an inlet rail  5  via a first connection  3 . The high pressure store is supplied with a liquid which is under pressure via inlet rail  5 . 
         [0025]    Inlet rail  5  has a first inlet  7  and a second inlet  9  for the liquid which is under pressure. 
         [0026]    A sealing cone  11  according to the present invention is accommodated in the connection between inlet rail  5  and the high pressure store. Sealing cone  11  is designed as a double cone. A high-pressure filter  13  is integrated into sealing cone  11 . 
         [0027]    For indicating clogging of high-pressure filter  13 , a first pressure sensor  15  is positioned on inlet rail  5 , and a second pressure sensor  17  is positioned on the high pressure store. The pressure of the liquid in inlet rail  5  is measured by first pressure sensor  15 . Second pressure sensor  17  measures the pressure in the high pressure store. If there is a pressure difference between inlet rail  5  and the high pressure store, it must be assumed that high-pressure filter  13  is clogged. 
         [0028]    In the specific embodiment illustrated here, three pressure control valves  19  are connected to the high pressure store. A second sealing cone  21  is present at the connection between pressure control valve  19  and the high pressure store. In contrast to sealing cone  11  between inlet rail  5  and the high pressure store, second sealing cone  21  between pressure control valve  19  and the high pressure store has a simple tapered design having a flat surface  23  on its top side facing pressure control valve  19 . For the sealing, a grip edge is provided on pressure control valve  19  and is pressed against flat surface  23 . In the process, the grip edge cuts into flat surface  23 , thus forming a media-tight connection. 
         [0029]    The outlet of each of pressure control valves  19  opens into a collector  25  in which the exiting liquid under a lower pressure is collected. 
         [0030]    In the specific embodiment illustrated here, the device has a connection  27  via which the high pressure store may be connected to another high pressure store having further devices. Liquid under high pressure may be removed from the high pressure store via connection  27 . 
         [0031]    Since the device heats up due to the high pressure, a cooling system is also provided. For this purpose, a cooling medium is supplied via an inlet  29 , flows around the high pressure store inside housing  1 , and is removed via an outlet  31 . In addition, a uniform temperature of the high pressure store may be achieved by the cooling. 
         [0032]    Sealing cone  11 , which in the specific embodiment illustrated here is positioned between inlet rail  5  and the high pressure store, is illustrated in detail in  FIG. 2 . 
         [0033]    Inlet rail  5  has a connecting piece  33  which is connected to the high pressure store via an inlet  35 . 
         [0034]    For the connection, connecting piece  33  is screwed to housing  1  with the aid of a union nut  37 . 
         [0035]    To be able to mount union nut  37  on connecting piece  33 , a thread  39  is formed on connecting piece  33 . After union nut  37  is mounted, a pressure ring  41  is screwed onto thread  39 . Pressure ring  41  has a top end face  43  on which union nut  37  abuts. 
         [0036]    To achieve a media-tight connection, a first seal seat  45  is provided in housing  1  in the area of inlet  35 . First seal seat  45  has a conical design. A second, likewise conical seal seat  47  is provided on connecting piece  33 . In the specific embodiment illustrated in  FIG. 2 , sealing cone  11  is designed as a double cone. A first taper  49  of sealing cone  11  abuts first seal seat  45 . A second taper  51  of sealing cone  11  abuts second seal seat  47 . 
         [0037]    To achieve a media-tight connection, first taper  49  of the sealing cone is pressed against first seal seat  45 , and second taper  51  of the sealing cone is pressed against second seal seat  47  with the aid of union nut  37 . 
         [0038]    A media-tight connection is achieved in that the opening angle of first taper  49  and of second taper  51  is 0.5° to 5°, preferably 1° to 3°, in particular 2°, smaller than the opening angle of first seal seat  45  and of second seal seat  47 . 
         [0039]    By using sealing cone  11  designed as a double cone, it is possible to easily remove high-pressure filter  13  when it becomes soiled. For this purpose, union nut  37  is loosened and inlet rail  5  is taken off. After inlet rail  5  has been taken off, sealing cone  11  is freely accessible and may be removed. High-pressure filter  13  may be cleaned after sealing cone  11  has been removed. After the high-pressure filter is cleaned, sealing cone  11  may be reinserted and screwed in place in a media-tight manner with the aid of union nut  37 . 
         [0040]    Alternatively, if sealing cone  11  is damaged or if soiling of high-pressure filter  13  is not removable, it is also possible to replace sealing cone  11  with a new sealing cone. 
         [0041]    Due to the design of sealing cone  11  having the double cone, the high-pressure components are not damaged by the screwing and the pressure which is thus exerted on tapers  49 ,  51  of the sealing cone, i.e., the pressure acting on seal seats  45 ,  47 . Regular replacement or regular cleaning of high-pressure filter  13  is thus possible. 
         [0042]    In the specific embodiment illustrated in  FIG. 2 , high-pressure filter  13  is force-fitted into sealing cone  11 . Besides a force-fit for introducing pressure filter  13 , it is alternatively possible to screw high-pressure filter  13  into sealing cone  11 , for example, or to join high-pressure filter  13  to sealing cone  11  using a welding process. 
         [0043]    In particular for a high-pressure filter  13  screwed in place, it is possible to remove only high-pressure filter  13  when the filter is soiled or damaged, and replace it with a new high-pressure filter  13 . In this case, sealing cone  11  may be reused. 
         [0044]    A sealing cone in a second specific embodiment is illustrated in  FIG. 3 . 
         [0045]    In contrast to the sealing cone illustrated in  FIG. 2 , second sealing cone  21  illustrated in detail in  FIG. 3  has a taper  53  having a convex surface. In addition, second sealing cone  21  is not designed as a double cone, but instead has a flat surface  23  which acts as a second sealing surface. 
         [0046]    To achieve a media-tight connection, taper  53  having a convex shape is placed against a conical seal seat  55 . Due to the convex shape of taper  53 , a uniform force acts on seal seat  55  over the periphery of taper  53 . It is thus possible to compensate for fairly large tolerances. 
         [0047]    To connect pressure control valve  19  in a media-tight manner, grip edges  57  are provided on pressure control valve  19 . Grip edge  57  of pressure control valve  19  is pressed against flat surface  23  of sealing cone  11 . Grip edge  57  cuts into flat surface  23  of sealing cone  11 , thus forming a media-tight connection. However, due to the grip edge it is not possible to use second sealing cone  21  indefinitely. The cutting of grip edge  57  into flat surface  23  results in damage to second sealing cone  21 . Second sealing cone  21  is thus used as a wear and tear part which may be replaced. 
         [0048]    As an alternative to the specific embodiments illustrated in  FIGS. 2 and 3 , in the specific embodiment illustrated in  FIG. 2 , for example, it is possible to use a sealing cone having a conical sealing surface and a flat sealing surface, similar to the illustration in  FIG. 3 . In this case, a grip edge which cuts into the flat surface of the sealing cone would be provided on connecting piece  33 , for example. 
         [0049]    Furthermore, as an alternative to first taper  49  and second taper  51 , which are designed as cones, it is possible to use a taper having a convex shape, as illustrated in  FIG. 3 . Alternatively, it is also possible for only first taper  49  or only second taper  51 , for example, to have a convex shape. 
         [0050]    As an alternative to the specific embodiment illustrated in  FIG. 3 , it would be possible here to use a sealing cone that is designed as a double cone. In this case, a grip edge would not be provided on pressure control valve  19 , and instead, pressure control valve  19  would have to have a conical seal seat. 
         [0051]    Instead of the tapers having a convex shape as illustrated in  FIG. 3 , it is also possible to use a conical taper, as illustrated in  FIG. 2 .