Abstract:
In order to provide a seal for sealing a sealing gap between a first component and a second component, comprising a seal body with at least one sealing portion and at least one spring element for biasing the sealing portion against at least one of the components to be sealed, the spring element being at least partially arranged in a receiving space of the seal body, which seal is simply constructed and easily producible and nevertheless ensures a secure retention of the spring element in the receiving space, it is proposed that the spring element has at least one claw element, by means of which the spring element is interlocked with the seal body.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    The present disclosure relates to the subject matter of, and claims priority to, German Application No. 10 2011 080 970.8, filed on Aug. 15, 2011, the entire specification of which is incorporated herein by reference. 
       FIELD OF THE INVENTION 
       [0002]    The present invention relates to a seal for sealing a sealing gap between a first component and a second component, the seal comprising a seal body with at least one sealing portion and at least one spring element for biasing the sealing portion against one of the components to be sealed, the spring element being at least partially, preferably substantially completely, arranged in a receiving space of the seal body. 
       BACKGROUND OF THE INVENTION 
       [0003]    Seals of this type are known from the prior art. In particular, seals of this type are marketed by the company ElringKlinger Kunststofftechnik GmbH, 74321 Bietigheim-Bissingen, Germany, under the name “spring-assisted lip seal”. 
         [0004]    In order to secure the spring element against it moving out of the receiving space unintentionally, provided on the seal body of these known seals is a so-called retaining lug, past which the spring element is moved when the spring element is introduced into the receiving space and which forms an undercut, behind which the spring element latches in, so that the spring element is retained by the retaining lug in the receiving space. 
         [0005]    However, to produce the retaining lug, an additional turning work step is necessary, for which a separate turning tool is required. As this turning tool is relatively delicate, it wears very rapidly, in particular owing to fillers contained in the material of the seal body. The wear of the turning tool leads to the retaining lug no longer being perfectly turned. As a result, undesired pieces of fluff may occur, which can detach from the seal body during use of the seal and lead to problems in the tightness of the seal and to problems in the assembly containing the seal (for example to a clogging of nozzles or filters). 
         [0006]    The turning tool therefore has to be changed relatively often. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention is based on the object of providing a seal of the type mentioned at the outset, which is simply constructed and easily producible and nevertheless ensures a secure retention of the spring element in the receiving space. 
         [0008]    This object is achieved according to the invention with a seal having the features of the preamble of claim  1  in that the spring element has at least one claw element, by means of which the spring element is interlocked with the seal body. 
         [0009]    The present invention is therefore based on the idea of configuring the spring element itself in such a way that it positively and/or non-positively interlocks with the seal body in such a way that the spring element can no longer be unintentionally detached from the receiving space of the seal body. 
         [0010]    It is therefore no longer necessary in the seal according to the invention to provide the seal body with a retaining nose. 
         [0011]    As a result the otherwise necessary laborious CNC machining of the seal body including the high tool wear and the high cost outlay are dispensed with for the production of the retaining lug. Furthermore, the risk of the formation of undesired pieces of fluff on the retaining lug is dispensed with. 
         [0012]    The spring element of the seal according to the invention secures itself on the seal body. 
         [0013]    Basically, any suitable material, which is stable under the use conditions of the seal, is a possibility for the production of the seal body. 
         [0014]    In particular, the seal body may comprise a plastics material and may preferably be substantially completely produced from a plastic material. 
         [0015]    Possible plastic materials are, in particular, fluoropolymer materials. 
         [0016]    It is particularly favorable, in particular for use of the seal element in an aggressive environment, if the seal body comprises a polytetrafluoroethylene material and/or a polytetrafluoroethylene compound, and is preferably substantially completely formed from one of the materials mentioned. 
         [0017]    A polytetrafluoroethylene compound is to be taken to mean here a mixture of a polytetrafluoroethylene material and one or more fillers. 
         [0018]    The term polytetrafluoro ethylene (PTFE) also designates in this description and the accompanying claims, modified polytetrafluoroethylene materials, in which some of the fluorine atoms of the polytetrafluoroethylene are replaced by substituents. 
         [0019]    Since the requirement for delicate turning tools to produce a retaining lug has been dispensed with, PTFE compounds, which are, in particular, highly filled (in other words having a high proportion of fillers) and which are difficult to machine, can be used for the seal body of the seal according to the invention, without drastically increasing the CNC tool costs required to produce the seal body. 
         [0020]    Alternatively or in addition to this, it may also be provided that the seal body comprises a melt-processable TFE (tetrafluoroethylene) copolymer or a compound of a melt-processable TFE copolymer, and is preferably substantially completely formed from a melt-processable TFE copolymer of this type or from a compound of a melt-processable TFE copolymer of this type. 
         [0021]    Suitable melt-processable TFE copolymers are, in particular, described in EP 1 263 877 B1. 
         [0022]    A melt-processable TFE copolymer made of TFE and a fluorinated comonomer is preferably used in a proportion of less than 1 mol-%. 
         [0023]    The comonomer is preferably selected from
       hexafluoropropylene;   perfluoroalkyl vinyl ethers (in particular perfluoroethyl vinyl ether and perfluoropropyl vinyl ether);   perfluoro-(2,2-dimethyl-1,3-dioxole).       
 
         [0027]    In a special configuration of the seal, the seal body is configured as an injection-molded part, preferably from a melt-processable TFE copolymer or a compound of a melt-processable TFE copolymer. 
         [0028]    If the seal body has no retaining projection, in particular no retaining lug, to retain the spring element in the receiving space, the seal body is particularly easily producible as an injection-molded part, as the injection-molded seal body is then configured to be easily removed from the injection-molding tool. 
         [0029]    The spring element preferably has one or more claw elements, which are arranged on spread out web members of the spring element. 
         [0030]    Owing to the claw elements, the spring, which is interlocked with the seal body, automatically centers in the receiving space. The spring element therefore no longer moves relative to the boundary walls of the receiving space after its assembly on the seal body and is preferably positioned within the receiving space such that it exerts substantially the same biasing forces on mutually opposing sealing portions of the seal body, which abut different components to be sealed. As result, particularly uniform contact pressures of sealing lips of the sealing portions can be achieved on the respective sealed components, thus achieving a particularly good fluid-tightness of the seal according to the invention. 
         [0031]    Furthermore, the self-centering of the spring element in the receiving space of the seal body also means that the biasing force of the spring element on the sealing portions along the peripheral direction of the spring element is substantially constant. This also contributes to an evening out of the sealing lip contact pressures along the peripheral direction of the seal, which increases the fluid-tightness of the seal according to the invention and reduces the risk of leaks. 
         [0032]    In contrast to this, in the case of spring-assisted lip seals, in which the spring element is only retained in the receiving space by a retaining lug, the back of the spring element can move in the groove base because of tolerance stack-up of the groove geometry in the seal body and the spring geometry, so the spring element rests more on an inner sealing portion or more on an outer sealing portion. This results in the fact that the spring element exerts different biasing forces on the mutually opposing sealing portions of the seal body, which results in different sealing forces on the components to be sealed. 
         [0033]    Moreover, a spring element only retained in the receiving space of the seal body by a retaining lug is not automatically centered in the groove forming the receiving space, so different sealing lip contact pressures occur on the sealing portions of the seal body, which makes leaks possible. 
         [0034]    These drawbacks are avoided or at least reduced by the seal according to the invention, in which the spring element is interlocked with the seal body. 
         [0035]    Since the retaining lug on the seal body has been dispensed with, the danger no longer exists either of a retaining lug of this type being damaged during the assembly of the spring element on the seal body. Thus, no additional formation of pieces of fluff can occur either because of damage to a retaining lug. Furthermore, the danger also no longer exists of the spring element being displaced from the receiving space because of a defect on a retaining lug and thereby bringing about a failure of the seal. 
         [0036]    In a preferred configuration of the invention, it is provided that the spring element comprises a base body which is meandering in shape. 
         [0037]    At least one claw element may comprise at least one projection arranged on a base body of the spring element. 
         [0038]    If the seal body is annular, at least one claw element is preferably arranged on a peripheral direction portion of a base body of the spring element, which extends substantially along the peripheral direction of the seal body. 
         [0039]    The receiving space of the seal body may open at a mouth opening into an external space of the seal body. Owing to a mouth opening of this type, the spring element can be introduced at least partially into the receiving space of the seal body during the assembly of the seal. 
         [0040]    Furthermore, the receiving space of the seal body may be closed by an end wall or a groove base at a side opposing the mouth opening. 
         [0041]    The spring element preferably has at least two claw elements, which are arranged substantially at the same spacing from the mouth opening of the receiving space. As a result, a particularly precise self-centering of the spring element is achieved in relation to the receiving space. 
         [0042]    As an alternative or in addition to this, it may be provided that the spring element has at least two claw elements, which are arranged at different spacings from the mouth opening of the receiving space. This achieves a particularly uniform distribution of the resilient biasing force exerted by the spring element on the seal body along a longitudinal direction or axial direction of the spring element, the seal body and/or the seal. 
         [0043]    In a preferred configuration of the invention it is provided that the seal body comprises a first sealing portion, for example a radially outer sealing portion, for applying against the first component and a second sealing portion, for example a radially inner sealing portion, for applying against the second component, the spring element biasing the first sealing portion against the first component and the second sealing portion against the second component when the seal is in the assembled state. 
         [0044]    In this case, it is advantageous if the spring element has at least one claw element, which is interlocked with the first sealing portion, and has at least one claw element, which is interlocked with the second sealing portion. 
         [0045]    This achieves a particularly reliable securing of the spring element on the two sealing portions. 
         [0046]    As an alternative or in addition to this, it may be provided that the spring element has at least two claw elements, which are interlocked with the same one of the two sealing portions. 
         [0047]    The spring element preferably has at least one claw element, which is interlocked with the seal body on a boundary wall of the receiving space. This achieves a securing of the spring element on the seal body within the receiving space. 
         [0048]    As an alternative or in addition to this, it may also be provided that the spring element has at least one claw element, which is interlocked with the seal body outside the receiving space. In this manner, a securing of the spring element to the seal body is achieved outside the receiving space. 
         [0049]    A securing of the spring element to the seal body outside the receiving space may be achieved, in particular, in that the seal body has an end face arranged next to the receiving space, at least one claw element of the spring element being interlocked with the seal body at this end face. 
         [0050]    In a preferred configuration of the seal according to the invention, it is provided that the seal body has no retaining projection, in particular no retaining lug, to retain the spring element in the receiving space. 
         [0051]    The present invention furthermore relates to a method for producing a seal for sealing a sealing gap between a first component and a second component. 
         [0052]    The present invention is based on the further object of providing a method of this type, which is easily implementable and produces a seal with a spring element, which is securely retained (at least partially) in a receiving space of a seal body of the seal. 
         [0053]    This object is achieved according to the invention by a method for producing a seal for sealing a sealing gap between a first component and a second component, which comprises the following method steps:
       producing a seal body with at least one sealing portion and a receiving space;   producing a spring element with at least one claw element;   at least partially introducing the spring element into the receiving space of the seal body, the spring element being interlocked with the seal body by at least one claw element.       
 
         [0057]    Particular configurations of the method according to the invention have already been described above in conjunction with the seal according to the invention. 
         [0058]    The spring element of the seal according to the invention may have special, spread out interlocking web members. 
         [0059]    The spring element can be simply pressed into a receiving space of a seal body, that preferably does not have a retaining lug, and interlocks by means of spreading out web members with the seal body, in particular within the receiving space of the seal body in such a way that the spring element can no longer detach from the seal body. 
         [0060]    The receiving space of the seal body is preferably configured to be annular, in particular as an annular groove. 
         [0061]    The spring element may be interlocked with the seal body on one side or on both sides. 
         [0062]    The seal according to the invention is suitable, in particular, as a dynamic seal for sealing a sealing gap between two components, which are moveable relative to one another. 
         [0063]    The relative movement between the first component and the second component may, in this case, comprise a linear movement and/or a rotary movement. 
         [0064]    The seal according to the invention may, in particular, be used as a rod seal or piston seal or as a radial shaft sealing ring. 
         [0065]    The spring element preferably comprises a resilient metallic material, preferably a spring steel material, and is, in particular, substantially completely formed from a resilient metallic material of this type. 
         [0066]    Further features and advantages of the invention are the subject of the following description and the graphical view of embodiments. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0067]      FIG. 1  shows a schematic section through an assembly with a first component, a second component and a seal for sealing a sealing gap between the first component and the second component; 
           [0068]      FIG. 2  shows a schematic radial section through the seal of the assembly from  FIG. 1 ; 
           [0069]      FIG. 3  shows a schematic plan view of a spring element preform of a spring element of the seal from  FIGS. 1 and 2 ; 
           [0070]      FIG. 4  shows a schematic perspective partial view of a spring element of the seal from  FIGS. 1 and 2 ; 
           [0071]      FIG. 5  shows a schematic radial section through a second embodiment of the seal, in which the spring element has at least two claw elements interlocked with a first sealing portion of a seal body of the seal in different axial positions and at least one claw element interlocked with a second sealing portion opposing the first sealing portion; 
           [0072]      FIG. 6  shows a plan view of a spring element preform of the spring element of the seal from  FIG. 5 ; 
           [0073]      FIG. 7  shows a schematic perspective partial view of the spring element of the seal from  FIG. 5 ; 
           [0074]      FIG. 8  shows a schematic section through an assembly with a first component, a second component and a third embodiment of the seal for sealing the sealing gap between the first component and the second component, the spring element of the seal being interlocked with a first sealing portion by means of at least one claw element and with a second sealing portion of a seal body of the seal opposing the first sealing portion by means of at least one claw element; 
           [0075]      FIG. 9  shows a schematic radial cross-section through a fourth embodiment of the seal, the spring element of the seal being interlocked with the first sealing portion by means of at least one claw element and with the second sealing portion by means of at least one claw element; 
           [0076]      FIG. 10  shows a schematic radial cross-section through a fifth embodiment of the seal, the spring element being interlocked with the first sealing portion by means of at least one claw element and with the second sealing portion by means of at least one claw element; 
           [0077]      FIG. 11  shows a schematic radial cross-section through a sixth embodiment of the seal, the spring element being interlocked with the first sealing portion by means of at least one claw element, but not being interlocked with the opposing second sealing portion; 
           [0078]      FIG. 12  shows a schematic radial cross-section through a seventh embodiment of the seal, the spring element being interlocked with the first sealing portion by means of at least one claw element and with the second sealing portion by means of at least one claw element; 
           [0079]      FIG. 13  shows a schematic radial cross-section through an eighth embodiment of the seal, the spring element being interlocked with the first sealing portion by means of at least one claw element, which is arranged on an end of the spring element facing a mouth opening of a receiving space, in which the spring element is arranged, and being interlocked with the second sealing portion by means of at least one claw element, which is also arranged on an end of the spring element facing the mouth opening of the receiving space; 
           [0080]      FIG. 14  shows a schematic radial cross-section through a ninth embodiment of the seal, the spring element being interlocked with the first sealing portion by means of at least two claw elements, which are arranged in different axial positions, and with the second sealing portion by means of at least one claw element; 
           [0081]      FIG. 15  shows a schematic radial cross-section through a tenth embodiment of the seal, the spring element being interlocked with an end face of the first sealing portion by means of at least one claw element and with an end face of the second sealing portion by means of at least one claw element; 
           [0082]      FIG. 16  shows a schematic radial cross-section through the spring element of the seal from  FIG. 15 ; and 
           [0083]      FIG. 17  shows a schematic radial cross-section through an eleventh embodiment of the seal, the seal being configured as a double seal with two first sealing portions, two second sealing portions and two spring elements interlocked with the seal body. 
       
    
    
       [0084]    The same or functionally equivalent elements are designated by the same reference numerals in all the figures. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0085]    An assembly  100  shown partially in  FIG. 1  comprises an assembled first component  102 , which comprises a base part  104  and a seal holder  106 , a second component  108 , which is, for example, annularly surrounded by the first component  102 , and a seal  110  for sealing a sealing gap  112  between the first component  102  and the second component  108 . 
         [0086]    The seal holder  106  may also be configured in one piece with the base part  104  in this embodiment. 
         [0087]    The second component  108  is substantially cylindrical, at least in portions, with a longitudinal axis  114  and an external radius r (see  FIG. 1 ). 
         [0088]    The base part  104  of the first component  102 , annularly surrounding the second component  108 , has a stepped through-channel  116 , which has a narrower portion  118  with a radius R i  and a further portion  120  with a radius R a . 
         [0089]    The narrower portion  118  and the further portion  120  meet one another at a step  122  with an annular end face  124  running in a radial direction  126  of the assembly  100 . 
         [0090]    The seal  110  is arranged in the further portion  120  of the through-channel  116 . 
         [0091]    It comprises an annular seal body  128  with a substantially U-shaped radial cross-section. 
         [0092]    The seal body  128  comprises a first sealing portion  130 , which forms a radially outer leg of the seal body  128  and, when the seal  110  is in the assembled state, abuts with a first sealing lip  132  in a sealing manner on the first component  102 , in particular on the seal holder  106 ; a second sealing portion  134 , which forms a radially inner leg of the seal body  128  and, when the seal  110  is in the assembled state, abuts with a second sealing lip  136  on the second component  108 ; and an annular web  138 , which connects one end of the first sealing portion  130  to one end of the second sealing portion  134 . 
         [0093]    The two sealing portions  130  and  134  of the seal body  128  are separated from one another by a receiving space  140 , in particular in the form of an annular groove  142 , which extends proceeding from a mouth opening  145  on an open end face  144  of the seal body  128  along an axial direction  146  of the assembly  100  and the seal  110  into the seal body  128  and ends at a groove base  148 , which extends substantially in the radial direction  126  and is spaced apart in the axial direction  146  from a closed end face  150  of the seal body  128  also extending substantially in the radial direction  126 . 
         [0094]    The seal body  128  is preferably produced in one piece from a suitable plastics material. 
         [0095]    A fluoropolymer material, for example PTFE or a PTFE compound, in particular also modified PTFE or a modified PTFE compound is possible, in particular, as a suitable plastics material. 
         [0096]    The substantially rotationally symmetrical seal body  128  may, in particular, be produced from a substantially cylindrical base body by machining on a turning machine. 
         [0097]    As an alternative to this, the seal body  128  may also be produced, in particular, by injection-molding, from a melt-processable TFE copolymer or from a compound of a melt-processable TFE copolymer. 
         [0098]    In order to be able to produce the contact pressing force required for a fluid-tight seal relative to the first component  102  and relative to the second component  108  on the sealing lips  132  or  136 , the seal  110  furthermore comprises a spring element  152 , which is arranged in the receiving space  140 . 
         [0099]    As can best be seen from  FIGS. 1 ,  2  and  4 , the spring element  152  comprises a base body  154 , which is, for example, meandering in shape, with outer peripheral direction portions  156 , which extend, when the seal  110  is in the assembled state, substantially along a peripheral direction  158  of the seal body  128  and abut an outer boundary wall  160  of the receiving space  140  on the (radially inner) inside of the first sealing portion  130 , and with inner peripheral direction portions  162 , which, when the seal  110  is in the assembled state, extend substantially along the peripheral direction  158  of the seal body  128  and abut an inner boundary wall  164  of the receiving space  140  on the (radially outer) outside of the second sealing portion  134 . 
         [0100]    Outer peripheral direction portions  156 , which follow one another, in each case, in the peripheral direction  158 , on the one hand, and inner peripheral direction portions  162  of the spring element  152 , on the other hand, are connected to one another by connecting web members  166 , which are bent substantially in a U-shape in a radial cross-section, as can best be seen from  FIGS. 1 ,  2  and  4 . 
         [0101]    The spring element  152  has a multiplicity of outer peripheral direction portions  156  and inner peripheral direction portions  162 , in particular, in each case, at least ten outer peripheral direction portions  156  and inner peripheral direction portions  162 , preferably, in each case, at least twenty outer peripheral direction portions  156  and inner peripheral direction portions  162 , and a corresponding number of connecting web members  166 . 
         [0102]    In order to retain the spring element  152  in a simple and reliable manner in the receiving space  140  of the seal body  128 , the spring element  152  is provided with a plurality of, for example with two or more, preferably with four or more, claw elements  168 , which during the assembly of the spring element  152  on the seal body  128  interlock with the seal body  128  in such a way that the spring element  152  is interlocked with the seal body  128  by the digging of the claw elements  168  into the seal body  128  and is therefore fastened to the seal body  128 . 
         [0103]    As can best be seen from  FIGS. 1 ,  2  and  4 , each of the, for example, four claw elements  168  of the spring element  152  is arranged on a respective one of the rear outer peripheral direction portions  156   a  of the base body  154  of the spring element  152 . 
         [0104]    In connection therewith, the rear outer peripheral direction portions  156   a , on which the claw elements  168  are provided, are arranged closer to the crest line  170  of the spring element  152 , about which the connecting web members  166  of the spring element  152  are bent and along which the radius of curvature of the spring element  152  is smallest, than the front outer peripheral direction portions  156   b , which, when the seal  110  is in the assembled state, are arranged closer to the mouth opening  145  of the receiving space  140 . 
         [0105]    This is achieved in that the connecting web members  166   a , which connect the rear outer peripheral direction portions  156   a  to the inner peripheral direction portions  162  that are adjacent along the peripheral direction  158 , are shorter than in the other front outer peripheral direction portions  156   b  of the spring element  152 , which are further away from the crest line  170 . 
         [0106]    As can be seen, for example, from  FIG. 4 , the claw element  168  may comprise two projections  172 , which project from an outer peripheral direction portion  156   a  and between which an intermediate space  174  is arranged. 
         [0107]    Basically, the projections  172  could, however, also be arranged directly next to one another without an intermediate space. 
         [0108]    Furthermore, the number of projections  172  per claw element  168  may basically vary as desired; thus, each claw element  168  may, in particular, also comprise only one single projection  172  or more than two projections  172 , for example three projections  172 . 
         [0109]    In order to bias the claw element  168  against the boundary wall  160  of the receiving space  140 , in which the claw element  168  is to interlock, and to facilitate the claw element  168  entering the relevant boundary wall  160 , the claw element  168 , the rear outer peripheral direction portion  156   a  of the spring element  152 , on which the claw element  168  is arranged, and the radially outer portions  176 , which face the outer boundary wall  160  of the receiving space  140  when the seal  110  is in assembled state, of the connecting web members  166  of the spring element  152  connected to the rear outer peripheral direction portion  156   a  are inclined at an acute angle α relative to the axial direction  146  of the spring element  152 , which, when the seal  110  is in the assembled state, coincides with the axial direction  146  of the seal  110  and of the assembly  100  (see  FIG. 4 ). 
         [0110]    The axial direction  146  is oriented from the groove base  148  of the receiving space  140  toward the mouth opening  145 . 
         [0111]    The spring element  152  is preferably formed from a resilient metallic material, in particular from a spring steel material. 
         [0112]    Furthermore, the material of the spring element  152  is preferably a high-grade steel material, as a material of this type is suitable, in particular for use in aggressive media. 
         [0113]    The spring element  152  is produced by shaping a spring element preform  178  shown in plan view in  FIG. 3 . 
         [0114]    The spring element preform  178  is obtained by separating the spring element preform  178  with the contour shown, from a blank of the starting material, in particular a steel sheet. 
         [0115]    In the spring element preform  178 , which is firstly substantially flat, the connecting web members  166  are oriented substantially radially to a centre  180  of the spring element preform  178 , while the outer peripheral direction portions  156   a ,  156   b  and the inner peripheral direction portions  162  of the spring element  152  in the spring element preform  178  are oriented along the peripheral direction  158 . 
         [0116]    The crest line  170  of the spring element  152  in the spring element preform  178  runs in a circular manner around the centre  180  and substantially centrally between the outer peripheral direction portions  156  and the inner peripheral direction portions  162 . 
         [0117]    The spring element  152  of the seal  110  is produced from the spring element preform  178  shown in  FIG. 3 , in that the connecting web members  166  are bent about the crest line  170  such that the outer peripheral direction portions  156  and the inner peripheral direction portions  162  are oriented substantially parallel to the axial direction  146  or inclined at a small acute angle relative to the axial direction  146 , the rear outer peripheral direction portions  156   a , on which the claw elements  168  are arranged, being inclined at an angle α (for example in the range of about 20° to about 40°) relative to the axial direction  146  (see  FIG. 4 ). 
         [0118]    After this shaping process, the spring element  152  is introduced into the receiving space  140  of the seal body  128 , in particular pressed in, the spring element  152  automatically being centered in the annular receiving space  140  by the outwardly pointing outer portions  176  of the connecting web members  166   a , which form spread apart web members  182  of the spring element  152 . 
         [0119]    The claw elements  168  arranged on the spread apart web members  182  dig with their projections  172  into the outer boundary wall  160  of the receiving space  140 , so the spring element  152  is interlocked with the seal body  128  by means of the claw elements  168  in such a way that the spring element  152  can no longer detach from the seal body  128  and can no longer move out of the receiving space  140 . 
         [0120]    In order to promote the self-centering of the spring element  152  in the receiving space  140  and the interlocking of the spring element  152  with the seal body  128 , the spring element  152  has a plurality of claw elements  168 , in particular three claw elements  168  or more, preferably four claw elements  168  or more, the claw elements  168  preferably being distributed substantially equidistantly along the peripheral direction  158  of the spring element  152  (see in particular  FIG. 3 ). 
         [0121]    As the spring element  152  is held in the receiving space  140  of the seal body  128  owing to the interlocking by means of the claw elements  168 , it is not necessary to provide a retaining lug or other undercut to retain the spring element  152  in the receiving space  140  on the seal body  128  in the region of the receiving space  140 . 
         [0122]    The danger of a retaining lug of this type being damaged during the assembly of the spring element  152  in the receiving space  140  of the seal body  128  and thus pieces of fluff and/or burrs being able to be produced, which can impair the functionality of the assembly  100 , is avoided by the omission of the retaining lug on the seal body  128 . 
         [0123]    Furthermore, the necessity of carrying out a separate turning process with a delicate turning tool during the production of the seal body  128  is furthermore also dispensed with by the omission of the retaining lug on the seal body  128 . 
         [0124]    The seal body  128  may, therefore, in particular be formed from a highly filled PTFE compound which is difficult to machine. 
         [0125]    Owing to the omission of the retaining lug on the seal body  128 , the seal body  128  can also be produced in a simple manner by an injection-molding method, as the finished seal body  128  can easily be removed from the injection-molding tool without the retaining lug. 
         [0126]    In particular, the seal body  128  can therefore be produced by injection molding from a melt-processable TFE copolymer or from a compound of a melt-processable TFE copolymer. 
         [0127]    Furthermore, since the spring element  152  is also securely held on the seal body  128  without a retaining lug by means of the claw elements  168 , the danger is dispensed with of the spring element  152 , during operation of the seal  110 , displacing relative to the seal body  128  or even moving out of the receiving space  140 . 
         [0128]    The exact and permanent position of the spring element  152  in the receiving space  140  of the seal body  128  by means of the claw elements  168  also means that the spring element  152  exerts a particularly constant resilient biasing force along the peripheral direction on the first sealing portion  130  with the first sealing lip  132  and on the second sealing portion  134  with the second sealing lip  136 , so that particularly constant sealing lip pressures and therefore a particularly high fluid-tightness of the seal  110  are achieved. 
         [0129]    When the assembly  100  is assembled, the seal  110  is arranged with the spring element  152  inserted in the receiving space  140  of the seal body  128  between the first component  102  and the second component  108 . 
         [0130]    In connection therewith, the seal body  128  of the seal  110  abuts with deformation of the first sealing portion  130  with the first sealing lip  132  on a sealing face  184  of the first component  102 , in particular on a radially inner peripheral face of the seal holder  106 , and with deformation of the second sealing portion  134  with the second sealing lip  136  on a sealing face  186  of the second component  108 , in particular on the peripheral face of the cylindrical second component  108  (this deformation of the first sealing portion  130  and the second sealing portion  134  is therefore not taken into account in the schematic view of  FIG. 1 , which is why, in this schematic view, the first sealing lip  132  and the first component  102  and the second sealing lip  136  and the second component  108  overlap). 
         [0131]    When the assembly  100  is in the assembled state, the first sealing portion  130  substantially has the external radius R and the second sealing portion  134  has the internal radius r. 
         [0132]    Furthermore, the seal body  128 , when in the assembled state, preferably abuts with its closed end face  150  on the end face  124  of the base part  104  of the first component  102 . 
         [0133]    Owing to the seal at the first sealing lip  132  and the second sealing lip  136 , when the assembly  100  is in the assembled state, the seal  110  separates a first media space  188  and a second media space  190  from one another in a substantially fluid-tight manner. 
         [0134]    The media spaces  188  and  190  can therefore be filled with different fluid media, for example with air, fuel or oil, during operation of the assembly  100 . 
         [0135]    The second component  108  is preferably moveable relative to the first component  102  during operation of the assembly  100 . 
         [0136]    In connection therewith, the second component  108  may be rotatable relative to the first component  102  about the longitudinal axis  114  and/or may be displaceable along the longitudinal axis  114 , in other words in the axial direction  146  or counter to the axial direction  146 . 
         [0137]    In this case, the seal  110  preferably remains stationary with respect to the first component  102 . 
         [0138]    However, it may basically also be provided that the seal  110  is connected to the second component  108  in such a way that it moves together with the second component  108  relative to the first component  102 . 
         [0139]    When the seal  110  is stationarily arranged with respect to the first component  102 , the first sealing portion  130  of the seal  110  abutting the first component  102  is a static sealing portion, while the second portion  134  of the seal  110  abutting the second component  108  is a dynamic sealing portion. 
         [0140]    For example, the first media space  188  may be filled with an engine oil and the second media space  190  with another liquid, for example a fuel, in particular petrol. 
         [0141]    The assembly  100  may form a component of a high-pressure pump, in particular a high-pressure pump for injecting a fuel into an internal combustion engine. 
         [0142]    A second embodiment of a seal  110  shown in  FIGS. 5 to 7  differs from the first embodiment shown in  FIGS. 1 to 4  in that claw elements  168  are not only provided on individual outer peripheral direction portions  156  of the spring element  152 , but also on inner peripheral direction portions  162  of the spring element  152 . 
         [0143]    Furthermore, claw elements  168  are provided on outer peripheral direction portions  156   a  and  156   b , which are connected to connecting web members  166  of different lengths, so these various outer peripheral direction portions  156  are located at different axial positions of the spring element  152  (in other words at different positions with respect to the axial direction  146  of the spring element  152 ). 
         [0144]    The claw elements, which are arranged on the rear outer peripheral direction portions  156   a  will be called claw elements  168   a  below, the claw elements arranged on the front outer peripheral direction portions  156   b  will be called claw elements  168   b  and the claw elements arranged on the front inner peripheral direction portions  162   b  will be called claw elements  168   c.    
         [0145]    As can best be seen from  FIG. 6 , it may in particular be provided that all the rear outer peripheral direction portions  156   a  and all the front outer peripheral direction portions  156   b  and all the inner peripheral direction portions  162  are provided with a claw element  168  in each case. 
         [0146]    As can best be seen from  FIG. 7 , the claw elements  168   a  on the rear outer peripheral direction portions  156   a  are configured exactly as in the first embodiment shown in  FIGS. 1 to 4 . 
         [0147]    The claw elements  168   b  on the front outer peripheral direction portions  156   b  are in each case configured as a portion  194 , which is outwardly bent about a bend line  192 , of the respective front outer peripheral direction portion  156   b , the respective outwardly bent portion  194  being inclined relative to the axial direction  146  of the spring element  152  about an acute angle β, for example in the range of about 20° to about 40°. 
         [0148]    Each of these claw elements  168   b  may comprise a plurality of, for example two, projections  172  projecting from the outwardly bent portion  194  and, in each case, comprise an intermediate space  174  arranged in between. 
         [0149]    The claw elements  168   c  arranged on the inner peripheral direction portions  162  are configured, in this embodiment, as portions  198  bent inwardly about a bend line in each case, in other words bent toward the longitudinal axis  114  of the spring element  152 . 
         [0150]    These inwardly bent portions  198  are inclined relative to the axial direction  146  of the spring element  152  about an acute angle γ, for example in the range of about 20° to about 40°. 
         [0151]    The claw elements  168   c  on the inner peripheral direction portions  162  may, as shown in  FIG. 7 , only comprise the inwardly bent portions  198  of the inner peripheral direction portions  162 , just as the claw elements  168   a  and  168   b  on the outer peripheral direction portions  156   a  or  156   b  comprise one or more projections  172  projecting from the respective portion  198  bent inwardly. 
         [0152]    The spring element  152  of the second embodiment of the seal  110  is produced from the spring element preform  178  shown in  FIG. 6  by shaping the connecting web members  166  and by bending the outwardly bent portions  194  of the front outer peripheral direction portions  156  around the bend lines  192  and by bending the inwardly bent portions  198  of the inner peripheral direction portions  162  around the bend lines  196 . 
         [0153]    After these shaping processes, the spring element  152  is introduced into the receiving space  140  of the seal body  128 , where the spring element  152  interlocks by means of the claw elements  168   a  and  168   b  on the outer peripheral direction portions  156   a  and  156   b  with the outer boundary wall  160  of the receiving space  140  and interlocks by means of the claw elements  168   c  on the inner peripheral direction portions  162  with the inner boundary wall  164  of the receiving space  140 . 
         [0154]    Owing to the interlocking of the spring element  152  by means of claw elements  168  on the two mutually opposing boundary walls  160  and  164  of the receiving space  140  and owing to the interlocking of the spring element  152  by means of claw elements  168 , which are arranged at different axial positions of the spring element  152  and therefore at different spacings from the mouth opening  145  of the receiving space  140  and at different spacings from the groove base  148  of the receiving space  140 , a particularly secure hold of the spring element  152  on the seal body  128  and a particularly reliable centering of the spring element  152  on the seal body  128  are achieved. 
         [0155]    In connection therewith, the proportion of rear outer peripheral direction portions  156   a  on the total number of the outer peripheral direction portions  156  is basically selectable as desired. 
         [0156]    In the embodiment shown in  FIG. 6 , the number of rear outer peripheral direction portions  156   a  is, for example, four and the number of rear outer peripheral direction portions  156   a  is smaller than the number of front outer peripheral direction portions  156   b.    
         [0157]    However, the number of rear outer peripheral direction portions  156   a  may also basically be greater than the number of front outer peripheral direction portions  156   b.    
         [0158]    Otherwise, the second embodiment of a seal  110  shown in  FIGS. 5 to 7  coincides with respect to structure, mode of functioning and mode of production with the first embodiment shown in  FIGS. 1 to 4 , to the description of which reference is to this extent made. 
         [0159]    An alternative embodiment of an assembly  100 , shown in  FIG. 8 , with a third embodiment of the seal  110  differs from the first embodiment shown in  FIGS. 1 to 4  in that the seal body  128  in the third embodiment, in addition to the first sealing portion  130 , the second sealing portion  134  and the web  138 , comprises a holding portion  200  arranged radially outside the first sealing portion  130 , said holding portion comprising a projection  202  projecting in the axial direction  146 . When the seal  110  is in the assembled state, this projection is arranged in an intermediate space between the seal holder  106  and the end face  124  of the base part  104  and is squeezed axially against the seal holder  106 , so that an increased sealing pressing is obtained (this squeezing is not shown in the schematic view of  FIG. 8 ). As a result, the seal body  128  as a whole is secured against a displacement relative to the first component  102  in the radial direction  126 . 
         [0160]    Furthermore, in this embodiment of the seal  110 , the seal body  128  is provided with an additional wiper lip  206 , which, when the seal  110  is in the assembled state, abuts the sealing face  186  of the second component  108 , in other words, in particular on the peripheral face of a cylindrical second component  108 . 
         [0161]    Dirt particles from the first media space  188  are kept away from the second sealing portion  134  by this additional wiper lip  206 . 
         [0162]    The wiper lip  206  may, in particular, be configured as a memory wiper lip, in other words as a wiper lip, which is biased against the associated sealing face  186  by a memory effect of the fluoropolymer material used, in particular a PTFE or PTFE compound material, a melt-processable TFE copolymer or a compound of a melt-processable TFE copolymer. 
         [0163]    This memory effect comes about in that the memory wiper lip is firstly produced by machining with an internal diameter that is smaller than the external diameter of the second component  108 , and the memory wiper lip is then deformed, at room temperature or at an elevated temperature, in such a way that the second component  108  can be guided through the wiper lip  206 . During a heating of the assembly  100  during operation thereof, the PTFE-containing material of the memory wiper lip is deformed back in the direction of its original shape. Owing to this so-called “plastic memory effect”, the wiper lip  206  is therefore biased against the sealing face  186  and is continuously readjusted against the second component  108  in the course of the wear of the wiper lip  206  during operation of the assembly  100  so that an adequate wiper effect of the wiper lip  206  is always ensured. 
         [0164]    Furthermore, in the embodiment of the seal  110  shown in  FIG. 8 , the second sealing portion  134  does not only have a single sealing lip, but a plurality of, for example two or three, second sealing lips  136   a  and  136   b  following one another in the axial direction  146  as well as a substantially cylindrical contact face  208  resting on the sealing face  186  of the second component  108  when the assembly  100  is in the assembled state. 
         [0165]    A first leakage storage space  210  is formed between the front second sealing lip  136   a  and the rear second sealing lip  136   b , and a second leakage storage space  212  is formed between the rear second sealing lip  136  and the contact face  208  of the second sealing portion  134 . 
         [0166]    When the seal  110  is in the assembled state, the front second sealing lip  136   a , the rear second sealing lip  136   b  and the contact face  208  of the second sealing portion  134  abut the sealing face  186  of the second component  108 . The leakage of the medium out of the second media space  190  into the first media space  188  is significantly reduced by this triple or (when three second sealing lips are used) quadruple seal. 
         [0167]    When the second component  108  moves relative to the seal  110  counter to the axial direction  146  during operation of the assembly  100 , leakage liquid from the second media space  190  is stored in the leakage storage spaces  210  and  212  of the second sealing portion  134  and is urged back into the second media space  190  during the return movement of the second component  108  in the axial direction  146 , in particular during the return stroke of a piston arranged on the second component  108 . 
         [0168]    The spring element  152  of the seal  110  has, in this embodiment, just as in the embodiments shown in  FIGS. 1 to 7 , rear outer claw elements  168   a , which are arranged on rear outer peripheral direction portions  156   a  and by means of which the spring element  152  is interlocked with the outer boundary wall  160  of the receiving space  140  of the seal body  128 . 
         [0169]    In addition to this, the spring element  152 , in this third embodiment, has rear inner claw elements  168   d , which are arranged on rear inner peripheral direction portions  162   a  of the spring element  152  and are interlocked with the inner boundary wall  164  of the receiving space  140 . 
         [0170]    As can be seen from  FIG. 8 , the rear outer claw elements  168   a  and the rear inner claw elements  168   d  are substantially arranged at the same axial position of the spring element  152 , in other words at the same position along the axial direction  146 . 
         [0171]    The groove base  148  of the receiving space  140  may be curved in this embodiment and, in particular, be adapted to the curvature of the spring element  152  in the region of the crest line  170 . 
         [0172]    Otherwise, the third embodiment of the seal  110  shown in  FIG. 8 , coincides with respect to structure, mode of functioning and mode of production with the embodiments shown in  FIGS. 1 to 7 , to the above description of which reference is to this extent made. 
         [0173]    A fourth embodiment of the seal  110  shown in  FIG. 9 , differs from the first embodiment shown in  FIGS. 1 to 4  in that the spring element  152  of the seal  110  not only has at least one rear outer claw element  168   a , which is arranged on a rear outer peripheral direction portion  156   a  of the spring element  152  and is interlocked with the outer boundary wall  160  of the receiving space  140  of the seal body  128 , but, in addition, also has at least one rear inner claw element  168   d , which is arranged on a rear inner peripheral direction portion  162   a  and is interlocked with the inner boundary wall  164  of the receiving space  140  of the seal body  158 . 
         [0174]    Otherwise, the fourth embodiment of the seal  110  shown in  FIG. 9  coincides with respect to structure, mode of functioning and mode of production with the first embodiment shown in  FIGS. 1 to 4 , to the above description of which reference is to this extent made. 
         [0175]    A fifth embodiment of the seal  110  shown in  FIG. 10 , differs from the fourth embodiment shown in  FIG. 9  in that the claw elements  168   a  and  168   d  in this embodiment are bent back to such an extent relative to the axial direction  146  of the spring element  152  that the claw elements  168   a  and  168   d  with the axial direction  146  do not enclose an acute angle α, but a right angle or an obtuse angle α′ (see  FIG. 10 ). 
         [0176]    As a result, a particularly secure hold of the spring element  152  in the receiving space  140  of the seal body  128  is achieved. 
         [0177]    Otherwise, the fifth embodiment of the seal  110  shown in  FIG. 10  coincides with respect to structure, mode of functioning and mode of production with the fourth embodiment shown in  FIG. 9 , to the above description of which reference is to this extent made. 
         [0178]    A sixth embodiment of the seal  110  shown in  FIG. 11  differs from the first embodiment shown in  FIGS. 1 to 4  substantially only in that the rear outer claw elements  168   a  are arranged closer to the front edges of the front outer peripheral direction portions  156   b  of the spring element  152 . 
         [0179]    Furthermore, the groove base  148  of the seal body  128  in this embodiment (as also in the embodiments according to  FIGS. 9 and 10 ) may be curved and, in particular, be adapted to the curvature of the spring element  152  in the region of the crest line  170  of the spring element  152 . 
         [0180]    Otherwise, the sixth embodiment of the seal  110  shown in  FIG. 11  coincides with respect to structure, mode of functioning and mode of production with the first embodiment shown in  FIGS. 1 to 4 , to the above description of which reference is to this extent made. 
         [0181]    A seventh embodiment of the seal  110  shown in  FIG. 12  differs from the fifth embodiment shown in  FIG. 10  in that the rear outer claw elements  168   a  and the rear inner claw elements  168   d  on the spring element  152  are arranged so far to the rear that the ends of these claw elements  168   a ,  168   d  lie behind the crest line  170  of the spring element  152  in the axial direction  146 . As a result, it is particularly easy for the claw elements  168   a ,  168   d  to dig into the outer boundary wall  160  or into the inner boundary wall  164  of the receiving space  140  of the seal body  128  and to firmly lock there. 
         [0182]    Otherwise, the seventh embodiment of the seal  110  shown in  FIG. 12  coincides with respect to the structure, mode of functioning and mode of production with the fifth embodiment shown in  FIG. 10 , to the above description of which reference is to this extent made. 
         [0183]    An eighth embodiment of the seal  110  shown in  FIG. 13  differs from the fifth embodiment shown in  FIG. 10  in that the spring element  152 , instead of the rear outer claw elements  168   a  and the rear inner claw elements  168   d , has front outer claw elements  168   b , which are arranged on front outer peripheral direction portions  156   b  of the spring element and are interlocked with the outer boundary wall  160  of the receiving space  140  of the seal body  128 , and has front inner claw elements  168   c , which are arranged on front inner peripheral direction portions  162   b  of the spring element  152  and are interlocked with the inner boundary wall  164  of the receiving space  140  of the seal body  128 . 
         [0184]    Otherwise, the eighth embodiment of the seal  110  shown in  FIG. 13  coincides with respect to structure, mode of functioning and mode of production with the fifth embodiment shown in  FIG. 10 , to the above description of which reference is to this extent made. 
         [0185]    A ninth embodiment of the seal  110  shown in  FIG. 14  differs from the second embodiment shown in  FIGS. 5 to 7  only in that the claw elements  168   a ,  168   b  and  168   c  in the ninth embodiment enclose a larger angle α with the axial direction  146  of the spring element  152  than in the second embodiment. 
         [0186]    Furthermore, the base groove  148  of the receiving space  140  in the ninth embodiment, just as in the seventh embodiment shown in  FIG. 12  and in the eighth embodiment shown in  FIG. 13 , may be curved and, in particular, be adapted to the curvature of the spring element  152  in the region of the crest line  170 . 
         [0187]    Otherwise, the ninth embodiment of the seal  110  shown in  FIG. 14  coincides with respect to structure, mode of functioning and mode of production with the second embodiment shown in  FIGS. 5 to 7 , to the above description of which reference is to this extent made. 
         [0188]    A tenth embodiment of the seal  110  shown in  FIGS. 15 and 16  differs from the eighth embodiment shown in  FIG. 13  in that the front outer claw elements  168   b  and the front inner claw elements  168   c  are not interlocked with the boundary walls  160  or  164  of the receiving space  140  of the seal body  128 , but, instead, are interlocked with the open end face  144  of the seal body  128 . In this embodiment, the spring element  152  therefore partially extends out of the receiving space  140  of the seal body  128  through the mouth opening  145  of the receiving space  140 , 
         [0189]    Otherwise, the tenth embodiment of the seal  110  shown in  FIGS. 15 and 16  coincides with respect to structure, mode of functioning and mode of production with the eighth embodiment shown in  FIG. 13 , to the above description of which reference is to this extent made. 
         [0190]    An eleventh embodiment of the seal  110  shown in  FIG. 17  differs from the third embodiment shown in  FIG. 8  in that in this eleventh embodiment of the seal  110 , the seal  110  is configured as a double seal, which comprises not only one, but two second sealing portions  134   a  and  134   b  spaced apart from one another in the axial direction  146  with two respective second sealing lips  136   a ,  136   b  for sealing relative to the second component  108  and not only one, but two first sealing portions  130   a ,  130   b  with a first respective sealing lip  132  for sealing relative to the first component  102 . 
         [0191]    The seal  110  configured as a double seal may, in particular, be substantially mirror-symmetrical with respect to a transverse centre plane  214  of the seal  110  oriented perpendicular to the axial direction  146  and running through the cylindrical contact face  208 . 
         [0192]    The seal body  128  in this embodiment has two receiving spaces  140   a ,  140   b , which are in each case arranged between a first sealing portion  130   a ,  130   b  and an opposing second sealing portion  134   a  or  134   b , a respective spring element  152   a ,  152   b  being at least partially received in each of the receiving spaces  140   a ,  140   b.    
         [0193]    Each of the spring elements  152   a ,  152   b  of the seal  110 , in this embodiment, just as in the embodiment shown in  FIG. 8 , has rear outer claw elements  168   a  arranged on rear outer peripheral direction portions  156   a , by means of which the respective spring element  152   a ,  152   b  is interlocked with the outer boundary wall  160  of the respective receiving space  140   a  or  140   b  of the seal body  128 . 
         [0194]    In addition to this, each of the spring elements  152   a ,  152   b , just as in the embodiment shown in  FIG. 8 , has rear inner claw elements  168   d , which are arranged on rear inner peripheral direction portions  162   a  of the respective spring element  152   a ,  152   b  and are interlocked with the inner boundary wall  164  of the respective receiving space  140   a ,  140   b.    
         [0195]    As can be seen from  FIG. 17 , the rear outer claw elements  168   a  and the rear inner claw elements  168   d  are substantially arranged at the same axial position of the respective spring element  152   a ,  152   b , in other words at the same position along the axial direction  146 . 
         [0196]    The groove bases  148  of the receiving spaces  140   a ,  140   b  may be curved in this embodiment, and in particular adapted to the curvature of the respective spring element  152   a ,  152   b  in the region of the crest line  170 . 
         [0197]    In the assembly  100  shown in  FIG. 17 , the first component  102  may be formed in one piece and the holding portion  200  of the seal body  128  from  FIG. 8  may be dispensed with in this embodiment. 
         [0198]    Furthermore, it may be provided that the assembly  100  comprises a, preferably resilient, holding ring  216 , which is arranged on a side of the seal  110  remote from the end face  124  of the first component  102 , so the seal body  128  is held between the holding ring  216  and the end face  124  of the first component  102  and held by a positive-locking fit and secured against displacement along the axial direction  146 . 
         [0199]    The wiper lip  206  of the embodiment from  FIG. 8  may be dispensed with in the eleventh embodiment from  FIG. 17 ; it would also be possible to additionally arrange a wiper lip  206  of this type on a free end of one of the two second sealing portions  134   a ,  134   b.    
         [0200]    Otherwise, the eleventh embodiment of the seal  110  shown in  FIG. 17  coincides with respect to structure, mode of functioning and mode of production with the third embodiment shown in  FIG. 8 , to the above description of which reference is to this extent made.