Abstract:
A clip connection for coupling at least two components together, e.g., for fastening a first component to a second component in a joining direction, may include a plug-in pin arranged on the first component and having a longitudinal center axis extending parallel to the joining direction. The pin may include a conical longitudinal section that tapers in the joining direction. A radially resilient engagement hook may be provided engageable with an engagement contour. A sleeve may be arranged on the second component and have a longitudinal center axis extending parallel to the joining direction. The sleeve may include a plurality of radially resilient spring elements having a free end that supports the plurality of spring elements on the conical longitudinal section of the pin under radial preload when the sleeve and the pin are plugged together. The pin may be pluggable into the sleeve in the joining direction.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to German Patent Application No. 10 2014 206 255.1, filed Apr. 2, 2014, and International Patent Application No. PCT/EP2015/056903, filed Mar. 30, 2015, both of which are hereby incorporated by reference in their entirety. 
     TECHNICAL FIELD 
     The present invention relates to a clip connection for fastening without tools a first component to a second component in a joining connection. The invention additionally relates to an assembly, in particular of a vehicle, in which at least two components are fastened to one another by means of at least one such clip connection. 
     BACKGROUND 
     Clip connections are widely distributed and are mainly used in particular when as part of as simple and economical as possible an assembly two components have to be fastened to one another. Particularly practical clip connections are usable without tools which extremely simplifies their handling. 
     A clip connection comprises at least one plug-in pin with the help of which a first component can be fixed to a second component. To this end, the plug-in pin passes through an opening in the first component and an opening in the second component aligned with the former, wherein the plug-in pin with a head supports itself on the first component and engages on the second component with engagement elements. It is likewise possible to fasten the plug-in pin fixed on the first component so that during the joining the plug-in pin merely has to be plugged into the opening of the second component. In addition to such simple, one-piece clip connections there also exist multi-piece clip connections, which in addition to the plug-in pin comprise a sleeve into which the plug-in pin can be plugged in the joining direction. With such multi-piece clip connections, one-sided clip connections and two-sided clip connections can be distinguished. Examples for one-sided clip connections are known from U.S. Pat. No. 4,276,806, U.S. Pat. No. 4,927,287 and U.S. Pat. No. 6,364,586 B1. With these known multi-piece, one-sided clip connections, the sleeve is initially plugged through an opening in the first component and an opening in the second component that is aligned with the former, until engagement elements of the sleeve engage on the second component. At the same time, a collar of the sleeve lies against the first component. With the help of the plug-in pin, this engagement connection can now be locked in that the plug-in pin is plugged into the sleeve in the joining direction. Because of this, the plug-in pin locks the radially resilient engagement element of the sleeve. The plug-in pin in turn can comprise engagement elements which then engage with a corresponding engagement contour of the sleeve. Such multi-piece plug connections are one-sided, since both originate from the first component and bring about a locked engagement with the second component. 
     In contrast with this, the plug-in pin and the sleeve, in the case of a multi-piece, two-sided clip connection, are arranged on different components. Such two-sided clip connections require more effort on the component side but facilitate the assembly. 
     Independently of the one-piece or multi-piece as well as independently of the one-sided or two-sided configuration of the respective clip connection there is the basic problem with each clip connection that the radially resilient engagement elements have to be moved in the joining direction slightly beyond the associated engagement contour so that they can engage with the engagement contour. Because of this, conventional clip connections of necessity have axial play. Such axial play however cannot be tolerated in a plurality of assemblies so that no clip connections are used there. 
     SUMMARY 
     The present invention deals with the problem of stating an improved embodiment for a clip connection which is characterized in particular by reduced axial play and preferentially by eliminated axial play. 
     According to the invention, this problem is solved through the subjects of the independent claims. Advantageous embodiments are subject of the dependent claims. 
     The invention is based on the general idea with a two-sided multi-piece clip connection, to equip the plug-in pin with a conical longitudinal section which tapers towards the engagement hooks in the joining direction. The associated sleeve is equipped with radially resilient spring elements which in the connected state of the clip connection axially support themselves on the aforementioned conical longitudinal section of the plug-in pin. The clip connection additionally comprises multiple engagement hooks which are radially resilient with respect to the joining direction and at least one engagement contour configured corresponding to the engagement hooks for engaging the engagement hooks. Here, the engagement hooks engage with the respective engagement contour when the plug-in pin is plugged into the sleeve deep enough. The engagement hooks can be arranged on the plug-in pin so that the respective engagement contour can then be provided on the sleeve or on the second component comprising the sleeve. A converse design is also conceivable, in the case of which the engagement hooks are arranged on the sleeve while the respective engagement contour is provided on the plug-in pin or on the first component comprising the plug-in pin. 
     Furthermore, these spring elements are matched to the conical longitudinal section so that they lie against the same under radial preload while the engagement hooks axially lie against the respective engagement contour. The radial preload of the spring element results in an axial preload of the entire sleeve in the joining direction or in an axial preload of the plug-in pin against the joining direction. Thus, the engagement hooks are axially preloaded or pressed against the engagement contour. Through the interaction of the spring elements and the conical longitudinal section, any axial play between the engagement hooks and the respective engagement contour is thus eliminated so that the clip connection introduced here is axially free of play. Accordingly, the clip connection introduced here can also be employed with assemblies in the case of which components have to be fastened to one another without play. 
     Preferred is an embodiment in which the engagement hooks are integrally moulded on the plug-in pin distally from the first component while the respective engagement contour is integrally moulded on the sleeve or on the second component. Because of this, the clip connection has a structure that can be produced in a particularly simple manner. 
     According to an advantageous embodiment, the plug-in pin can have a cylindrical longitudinal section from the free face end of which the engagement hooks originate and which adjoins the conical longitudinal section. Because of this, the plug-in pin has a structure that can be produced in a particularly simple manner. Preferred in this case is an embodiment in the case of which exactly two engagement hooks are provided, which with respect to the longitudinal centre axis of the plug-in pin are located diametrically opposite one another. However, three or more engagement hooks can also be provided in principle. 
     According to an advantageous further development, the sleeve in its interior can comprise at least one axial stop which axially interacts with the aforementioned face end of the cylindrical longitudinal section of the plug-in pin in order to delimit to a predetermined value a plug-in depth for the plug-in pin with which the plug-in pin can be plugged into the sleeve. Here, the respective axial stop and the face end are matched to one another so that between the respective axial stop and the face end an axial distance is present when the engagement hooks axially lie against the respective engagement contour. Through this measure, plugging the plug-in pin too deeply into the sleeve is prevented as a result of which for example the risk of damaging the spring elements can be reduced. 
     With another embodiment, the spring elements can be arranged distributed on the sleeve in the circumferential direction, wherein the spring elements axially project from the sleeve and are separated from one another in the circumferential direction by way of axial slots. Because of this, the spring elements can radially move independently of one another in order to create the radial preload with respect to the conical longitudinal section. 
     In the case of another advantageous embodiment, the free ends of the spring element can form a chamfered insertion region of the sleeve. During the assembly, the plug-in pin is plugged into the sleeve in the region of the free ends of the spring elements. Through the insertion region provided there, the inserting of the plug-in pin into the sleeve is simplified. 
     According to another embodiment, a common engagement contour for all engagement hooks can be provided on the sleeve which is formed by a face end of the sleeve. Because of this, the sleeve has a structure that can be produced in a particularly simple manner. 
     According to another embodiment, the sleeve in its interior can comprise guide grooves for axially guiding the engagement hooks during the plug-in pin operation. With the help of such guide grooves it can be ensured that the plug-in pin can be properly inserted into the sleeve only in a predetermined rotational position relative to the sleeve. Because of this, the assembly can be simplified. 
     According to another embodiment, the engagement hooks can be arranged on the sleeve while the respective engagement contour is arranged on the plug-in pin or on the first component. Practically, the engagement hooks are also moulded integrally on the sleeve. Likewise, the respective engagement contour can be integrally moulded on the plug-in pin or on the first component. This design is less compact but can be designed for greater forces of misuse, which are orientated opposite to the joining direction. 
     According to a further development, the engagement hooks can be arranged on the sleeve radially outside and extend parallel to the joining direction. In particular, the free ends of the engagement hooks and the free ends of the spring elements are orientated in the joining direction and face the first component because of this. 
     In another embodiment, a locking element can be provided in the sleeve which impedes or prevents radial disconnecting of the engagement hooks from the respective engagement contour. Such a locking element can be provided as a separate that is additional third component of the clip connection. Such a locking element can be plugged into the interior of the sleeve against the joining direction for example in the region of the engagement contour. Likewise it is possible, in principle, to configure the plug-in pin hollow so that the locking element, passing through the plug-in pin for example, is adjustable in the joining direction as far as into the region of the engagement contour. The locking element can also be adjustably mounted on the plug-in pin parallel to the joining direction. During the plug-in pin operation, the locking element is adjusted into an unlocking position, in which it does not interfere with the radial movability of the engagement hooks. Following the plug-in pin operation, i.e. following the engaging of the engagement hooks on the respective engagement contour, the locking element can be adjusted into a locking position in which it then prevents or at least impedes the radial adjustability of the engagement hooks. 
     Particularly advantageous is an embodiment, in which the plug-in pin is integrally moulded on the first component. Additionally or alternatively, the sleeve can be integrally moulded on the second component. By integrally moulding the plug-in pin on the first component or the sleeve material-uniformly on the second component, the plug-in pin is material-uniformly produced from one piece with the first component or the sleeve with the second component. For example, the plug-in pin and the first component are injection moulded from plastic. Likewise, the sleeve and the second component can also be injection moulded from plastic. 
     With an assembly according to the invention, which can be employed in particular with a vehicle, a first component and a second component are fastened to one another by means of at least one clip connection of the type described above. Provided that multiple clip connections of this type are employed simultaneously in order to fasten the first component to the second component it is practical to arrange all plug-in pins on the first component while all sleeves are arranged on the second component. In principle, however, a mixed design is also conceivable so that each component comprises at least one plug-in pin and at least one sleeve. 
     The one in particular first component can for example be a suction module for a fresh air system of an internal combustion engine, wherein in a suction module housing a flap arrangement for controlling fresh air ducts is arranged. The plug-in pins are integrally moulded for example on the module housing. The other, in particular second component can then for example be an actuating drive for actuating the flap arrangement. The sleeves in this case can be integrally moulded on a drive housing of the actuating drive. Thus, the actuating drive can be particularly easily fastened to the suction module without play with the help of the clip connections. 
     Further important features and advantages of the invention are obtained from the subclaims, from the drawings and from the associated figure description by way of the drawings. 
     It is to be understood that the features mentioned above and still to be explained in the following cannot only be used in the respective combination stated but also in other combinations or by themselves without leaving the scope of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Preferred exemplary embodiments of the invention are shown in the drawings and are explained in more detail in the following description, wherein same reference characters relate to same or similar or functionally same components. 
       The drawings shows, in each case schematically, 
         FIG. 1  a highly simplified lateral view of a clip connection in a plugged-in state, 
         FIG. 2  a lateral view of a plug-in pin of the clip connection, 
         FIG. 3  a lateral view of a sleeve of the clip connection, 
         FIG. 4  an isometric view of an assembly, in which a first component and a second component are fastened to one another by means of multiple clip connections, 
         FIG. 5  an isometric view as in  FIG. 4 , however with another embodiment of the clip connections, 
         FIG. 6  an isometric view as in  FIG. 5 , however with absent second component. 
     
    
    
     DETAILED DESCRIPTION 
     According to  FIG. 1 , a clip connection  1 , with the help of which a first component  2  can be fastened without tools to a second component  3  in a joining direction  4  indicated by an arrow, comprises a plug-in pin  5  that is arranged fixed on the first component  2  and a sleeve  6  that is arranged fixed on the second component  3 . According to the  FIGS. 1 and 2 , a longitudinal centre axis  7  of the plug-in pin  5  runs parallel to the joining direction  4 . The plug-in pin  5  comprises a conical longitudinal section  8  proximally with respect to the first component  2 , which tapers with increasing distance from the first component  2  or in the joining direction  4 . 
     According to the  FIGS. 1 and 3 , a longitudinal centre axis  9  of the sleeve  6  runs parallel to the joining direction  4 . Furthermore, the sleeve  6  comprises multiple radially resilient spring elements  10 , which axially project from the sleeve  6 . In the plugged state of  FIG. 1 , the spring elements  10  support themselves with their free ends  11 , which are arranged distally from the sleeve  6 , on the conical longitudinal section  8  of the plug-in pin  5  in such a manner that they lie against the same under radial preload. Through the conicity of the conical longitudinal section  8 , the sleeve  6  is thereby driven in the joining direction  4  relative to the plug-in pin  5 . As reaction thereto, the plug-in pin  5  is driven against the joining direction  4  relative to the sleeve  6 . 
     According to  FIGS. 1 to 3 , the clip connection  1  additionally comprises multiple radially resilient engagement hooks  12 , which in the plugged-in state are engaged with at least one engagement contour  13  that is complementary to the former. Here, the engagement lugs  14  of the engagement hooks  12  radially engage behind said engagement contour  13  in such a manner that the engagement hooks  12  via their engagement lugs  14  support themselves opposite to the joining direction  4  on the engagement contour  13 . Through the axial preload between sleeve  6  and plug-in pin  5 , the engagement hooks  12  are axially preloaded for lying against the engagement contour  13 . Accordingly, the clip connection  1  in the plugged state is axially free of play. In the embodiment shown in the  FIGS. 1 to 4 , the engagement hooks  12  are arranged on the plug-in pin  5  distally from the first component  2 . 
     In particular, the engagement hooks  12  are integrally moulded on the plug-in pin  5 . The respective engagement contour  13  in this case is integrally moulded on the sleeve  6 . In principle, an embodiment is also conceivable in which the engagement contour  13  is formed on the second component  3 . The plug-in pin  5  can thus be plugged into the sleeve  6  in the joining direction  4  with the engagement hooks  12  up front. In the process, the engagement hooks  12  penetrate an interior enclosed by the sleeve  6 . 
     In the shown example of the  FIGS. 1 to 4 , the plug-in pin  5  comprises a cylindrical longitudinal section  15 , from the free face end  16  of which the engagement hooks  12  project, and which axially adjoins the conical longitudinal section  8 . The free face end  16  of the cylindrical longitudinal section  15  faces away from the conical longitudinal section  8 . According to  FIG. 1 , the sleeve  6  can now comprise in its interior at least one axial stop  17  which is indicated by an interrupted line. The axial stop  17  in this case radially projects towards the inside between two engagement hooks  12  which are adjacent in the circumferential direction. Preferentially, exactly two engagement hooks  12  are provided which are arranged diametrically opposite one another. The respective axial stop  17  now radially projects into the gap between the two engagement hooks  12 . Because of this, the axial stop  17  can axially interact with the face end  16  in order to limit a plug-in depth for the plug-in pin  5  to a predetermined value. Here, the respective axial stop  17  and the face end  16  are matched to one another so that in the plugged state shown in  FIG. 1 , in which the engagement hooks  12  with their engagement lugs  14  axially lie against the respective engagement contour  13 , an axial distance  18  between the respective axial stop  17  and the face end  16  is present. In this way, a tolerable over-plugging of the plug-in pin  5  into the sleeve  6  is made possible. 
     In the embodiment shown in the  FIGS. 1 to 4 , a common engagement contour  13  is provided for all engagement hooks  12 , which is formed by an axial face end  19  of the sleeve  6  facing away from the spring elements  10 . Furthermore, the sleeve  6 , with this embodiment, can comprise in its interior guide grooves which are not noticeable here for axially guiding the engagement hooks  12  during the plug-in operation. The guide grooves in this case are orientated parallel to the longitudinal centre axis  9  of the sleeve  6 . The engagement hooks  12  radially engage in the guide grooves, as a result of which a slot and key guide is formed. 
     In the embodiment shown in the  FIGS. 5 and 6 , the engagement hooks  12  are arranged on the sleeve  6 , in particular integrally moulded thereon. The respective engagement contour  13  in this case is arranged on the plug-in pin  5  or on the first component  2 . Here, too, exactly two engagement hooks  12  are provided which are located diametrically opposite one another. The associated engagement contour  13  in the example is formed on a support  20  in each case, from which the plug-in pin  5  originates and which in this case forms an integral part of the first component  2 . In this embodiment, the engagement hooks  12  are arranged on the sleeve  6  radially outside, while extending parallel to the joining direction  4 . 
     In the embodiment shown in the  FIGS. 5 and 6 , the free ends  11  of the spring elements  10  and the free ends of the engagement hooks  12  carrying the engagement lugs  14  are orientated in the same direction, namely in each case in the joining direction  4 . In contrast with this, it is provided in the embodiment shown in the  FIGS. 1 to 4  that the free ends of the engagement hooks  12  are orientated opposite to the free ends  11  of the spring elements  10 . While the free ends of the engagement hooks  12  extend in the joining direction  4 , the free ends  11  of the spring elements  10  extend opposite to the joining direction  4 . 
     With the embodiment shown in the  FIGS. 5 and 6 , the interaction of the spring elements  10  with the conical longitudinal section  8  also results in an elimination of the axial play between the plug-in pin  5  and sleeve  6 , so that this clip connection  1  is also axially free of play. 
     In the case of the embodiment shown in the  FIGS. 1 to 6 , the spring elements  10  are arranged on the spring  6  distributed in the circumferential direction, wherein they axially project from the sleeve  6  in each case and are separated from one another in the circumferential direction by axial slots  21 . Furthermore, the free ends  11  of the spring elements  11  are radially chamfered on the inside in order to form a chamfered insertion region  22  of the sleeve  6 . This insertion region  22  simplifies inserting the plug-in pin  5  into the sleeve  6  during the plug-in operation. 
     According to the  FIGS. 1 and 2 , a locking element  23  can be provided which prevents or at least impedes a radial disconnecting of the engagement hook  12  from the respective engagement contour  13 . In the example indicated in  FIG. 1 , the locking element  23  is a separate element subsequently inserted into the sleeve  6 , which impedes the radial movability of the engagement hooks  12 . This locking element  23  in this case is inserted into the sleeve  6  on the face end  19  facing away from the spring elements  10 . 
     In contrast with this, another embodiment is indicated in  FIG. 2 , in the case of which such a locking element  23  is adjustably arranged on the plug-in pin  5 . Here, an unlocking state and a locking state of the locking element  23  are indicated by a continuous line and an interrupted line respectively. In the unlocking state, a detent  24  of the locking element  23  lies for example against the face end  16  of the cylindrical section  15 . In the locking state, the detent  24  by contrast is adjusted as far as into the region of the engagement lugs  14 . Adjusting the detent  24  can be effected for example by means of a rod  25 , which extends through a central opening  26  of the plug-in pin  5 , so that the locking element  23  following the insertion of the plug-in pin  5  into the sleeve  6  and following the engagement of the engagement hooks  12  with the respective engagement contour in the joining direction  4  can be transferred into a locked position. 
     As is indicated in the  FIGS. 4 to 6 , the respective plug-in pin  5  is practically moulded integrally on the first component  2 . In particular, the first component  2  is a one-piece injection moulded part produced from plastic. Similar applies also to the respective sleeve  6  which is preferably integrally moulded on the second component  3 . The second component  3  is preferably also an injection moulded part produced in one piece, preferentially from plastic. 
     The  FIGS. 4 to 6  show an assembly  27 , which comprises at least the first component  2  and the second component  3 . Here, the first component  2  and the second component  3  are connected to one another with the help of at least one clip connection  1  of the type mentioned above. In the examples of  FIGS. 4 to 6 , three clip connections  1  are provided in each case in order to fasten the two components  2 ,  3  to one another. 
     The one component is purely exemplarily a suction module  28 , which in a suction module housing  29  comprises a flap arrangement, of which a flap shaft  30  is noticeable only in  FIG. 6 . By turning the flap shaft  30 , multiple flaps for controlling fresh air ducts are adjusted within the module housing  29 . In the example shown in  FIG. 4 , the suction module  28  forms the second component  3  which comprises the sleeves  6 . In contrast with this,  FIGS. 5 and 6  show an example in the case of which the suction module  28  forms the first component  2 , which comprises the plug-in pins  5 . 
     On the module housing  29 , a support  20  is formed for each clip connection  1 , which in the region of  FIGS. 5 and 6  in each case comprises a plug-in pin  5  with conical longitudinal section  8 . In the example of  FIG. 4 , by contrast, the sleeve  6  is arranged on the support  20 , while the spring elements  10  are located distally from the support  20 . The other component in the present example is an actuating device  33 , which comprises for example a pressure capsule  31 . On an actuating device housing  32 , the plug-in pins  5  ( FIG. 4 ) or the sleeves  6  ( FIGS. 5 and 6 ) are arranged in each case depending on embodiment. In the example of  FIG. 4 , the actuating device thus forms the first component  2  while in the example of  FIGS. 5 and 6  it forms the first component  3 . 
     Accordingly, in the embodiment shown in  FIG. 4 , seemingly kinematically reversed with respect to the embodiment shown in the  FIGS. 5 and 6 , the sleeves  6  are arranged on the suction module housing  29  and the plug-in pins  5  on the actuating device housing  32 . Accordingly, the actuating device  33  in the example of  FIG. 4  forms the first component  2 , while the second component  3  is formed by the suction module  28 . 
     With the help of the clip connections  1 , the two components  2 ,  3 , i.e. actuating device  33  and suction module  28 , can be fastened to one another without tools, wherein in addition any play in the joining direction  4  can be additionally eliminated.