Abstract:
A fastening clip for attaching a component to a stud of a support part has a base part with an opening for accepting the stud. The opening has an axis and has a fastening region and an unlocking region located next to one another perpendicular to the axis. Resilient retaining means for holding the stud in place are arranged in the fastening region, which means are designed such that the stud can be introduced into the fastening region in the direction of the axis and the stud located in the fastening region can be displaced into the unlocking region by a relative movement of the stud and fastening clip perpendicular to the axis of the opening, wherein in the unlocking region the stud can be removed from the opening.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit and priority of German Application No. DE 10 2009 014 133.2, filed Mar. 24, 2009. The entire disclosure of the above application is incorporated herein by reference. 
     FIELD 
     The present disclosure relates to a fastening clip and an associated fastener for attaching a component to a stud of a support part, in particular a body part of a motor vehicle. 
     BACKGROUND 
     Fastening clips and fasteners are primarily used in automotive manufacture in order to attach mounted parts or trim parts to the body or to body parts such as door or the like. It should be possible to accomplish the attachment as easily as possible and without the aid of tools here, but the attachment should also be releasable in order to be able to carry out maintenance and repairs. On the one hand, the attachment should ensure high retention forces, but, on the other hand, it should permit nondestructive removal force. Moreover, it is frequently necessary to compensate for dimensional deviations in the parts in the region of the fasteners. 
     Various fasteners of the specified type are known, for example from EP 0,020,308 A1, EP 1,895,171 A2, U.S. Pat. No. 6,196,607 B1. The prior art fasteners have in common that a pin-like element is provided as a connecting part, which is connected to the support part in a locking manner by insertion in an opening of the support part. In this context, the support part must have openings at the fastening points with the result that additional means such as an umbrella-like washer, and possibly additional sealing rings, must be provided so that these openings can be tightly sealed during installation of the mounted or trim parts. 
     In addition, a device for fastening a sound insulating panel to the body of a motor vehicle is known from WO 02/072390 A1, in which the body has a stud on which can be placed a one-piece fastening element made of plastic. In this design, the fastening element made of plastic is arranged in an opening in the sound insulating panel, and an annular flange of the fastener engages around the sound insulating panel on the side facing away from the car body. Release of the attachment in this design can only be accomplished by overcoming the retention force, and may result in damage to the fastening element. 
     Furthermore, a plastic clip for fastening a trim strip to the body of a motor vehicle is known from EP 0,489,505 B1, which clip latches together with a T-shaped stud welded to the body panel and has lateral locking fingers that engage in opposing grooves on the inside of the trim strip that is bent in a U-shape. With this clip, too, release must take place in opposition to the retention force. 
     SUMMARY 
     According to the teachings herein, a fastening clip for fastening mounted or trim parts to a stud that permits a high retention force while also permitting a low removal force is provided. The joined parts can be nondestructively separated from one another again. Further, according to the present teachings, a fastener that does not require attachment openings in the parts to be joined together is provided. Moreover, the fastener should be easy to install and should be made of simple parts that are economical to manufacture. It should also make it possible to compensate for manufacturing-related dimensional deviations. 
     The fastening clip according to the present teachings has a base part with an opening for accepting a stud of a support part, wherein the opening has an axis and has a fastening region and an unlocking region located next to one another perpendicular to the axis, and wherein resilient retaining means for holding the stud in place are arranged in the fastening region, which means are designed such that the stud can be introduced into the fastening region in the direction of the axis and the stud located in the fastening region can be displaced into the unlocking region by a relative movement of the stud and fastening clip perpendicular to the axis of the opening, wherein in the unlocking region the stud can be removed from the opening. The fastening clip can be attached to the stud very easily by means of a movement in the axial direction of the opening, and the resilient retaining means for holding the stud in place can be designed such that a high axial retention force can be achieved, since the retention force need not be overcome to release the fastening clip. 
     Moreover, the resilient retaining means can be designed such that no great force is required to move the stud out of the retaining region into the unlocking region. Consequently, the fastening clip can be released easily and without great application of force, so that the danger of damage from the release process is also very small. The fastening clip remains unharmed in the release process, and can subsequently be reused to fasten a component. 
     A return lock can be provided in the opening of the fastening clip; once the stud has been moved into the unlocking region, said return lock opposes a return movement of the stud into the retaining region. This design is helpful when the part to be released is attached by means of fastening clips at two or more points. The release can then take place at one fastening point after the other, without the danger that a released point can return to the fastened state when the component is released at a second point. 
     The resilient retaining means of the fastening region can have at least one resilient locking finger, which extends inward from the edge of the opening in the direction of the axis and whose free end forms a locking tooth. Alternatively, the resilient retaining means can have two opposing, in particular symmetrically arranged, locking fingers. 
     Furthermore, the locking tooth of the locking finger can be straight and can extend parallel to the common center plane of the fastening region and unlocking region which contains the axis of the opening. In this way, the stud can be moved from the retaining region to the unlocking region without deformation of the locking finger. Furthermore, multiple adjacent retaining positions for the stud can be formed by the extension of the straight locking tooth, so that position deviations between the stud and clip can be compensated during the fastening of the parts. 
     The return lock can have a resilient locking finger which extends perpendicular to the axis of the opening at a distance from the resilient retaining means and bears a locking projection that projects into the displacement path of the stud and has a ramp surface facing the retaining region and a locking surface facing the unlocking region. The locking finger of the return lock can additionally be arranged such that it limits the penetration depth of the stud into the opening by contact with the end of the stud. Moreover, it is advantageous for the locking finger of the return lock to be located at the wall of the opening that delimits the retaining region and is opposite the unlocking region. 
     According to another proposal of the invention, the base part of the fastening clip can have an outwardly projecting flange that is meant for attaching the base part to a receptacle part. Moreover, a circumferential groove can be formed in the lateral surface of the base part adjacent to the flange if necessary. 
     The teachings further provide a fastener for attaching a component to a stud using an inventive fastening clip, wherein the component has a receptacle part, designed as a pocket with a lateral opening and with a pilot slot, in which the fastening clip can be inserted through the lateral opening. The receptacle part can be an integral part of the component or a separate structural element that is attached to the component by adhesive, for example. Preferably the receptacle part has a plate with an open pilot slot on one side of the plate, and has a U-shaped wall on one side of the plate that is arranged to project upright therefrom and surrounds the pilot slot at a distance. The upright wall in this design can be attached to a platelike part of the component at a distance from the plate. 
     In order to transmit axial retention forces to the receptacle part, provision is made that the fastening clip engages with the outwardly projecting flange in the pocket of the receptacle part, wherein the section of the fastening clip adjoining the flange extends through the pilot slot. The pilot slot preferably has a pilot section that grows larger toward the outside, and a narrow spot formed by retaining projections, which can be expanded by the fastening clip during installation of the same. Installation of the fastening clip is made easier by the pilot slot. The narrow spot ensures that the fastening clip is held in place after insertion in the receptacle part so that it cannot fall out of the receptacle part when the component is transported to the assembly site. 
     If the fastening clip is provided with a circumferential groove, provision can be made for the plate to engage in the groove with an edge region adjoining the pilot slot, thus determining the position of the fastening clip relative to the component in the axial direction. It is then possible to eliminate a supporting function of the component surface opposite the plate of the receptacle part. 
     Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
    
    
     
       DRAWINGS 
       The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure. 
         FIG. 1  is a perspective view of the back of a fastening clip according to the invention; 
         FIG. 2  is a perspective view of the front of a fastening clip from  FIG. 1 ; 
         FIG. 3  is a side view of the fastening clip from  FIG. 1 ; 
         FIG. 4  is a perspective view of a receptacle part for receiving the fastening clip from  FIG. 1 ; 
         FIG. 5  is a perspective view of the receptacle part from  FIG. 4  with the fastening clip from  FIG. 1  inserted; 
         FIG. 6  is a cross section through a fastener according to the invention joining two components together; 
         FIG. 7  is a longitudinal section through the fastener from  FIG. 6  in the fastened position; and 
         FIG. 8  is a longitudinal section through the fastener from  FIG. 6  in the released position. 
     
    
    
     Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings. 
     DETAILED DESCRIPTION 
     Example embodiments will now be described more fully with reference to the accompanying drawings. 
     Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail. 
     The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed. 
     When an element or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. 
     Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments. 
     Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature&#39;s relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. 
     The fastening clip  10  shown in  FIGS. 1 through 3  has a base part  11 , which is divided into two block-shaped sections  12 ,  13  of different size. In its center, the base part  11  has a rectangular opening  14 , which extends through both sections  12 ,  13  along an axis A and is shown open at both ends. It can also be closed at one end. The smaller section  12  has a smaller footprint and forms, together with its surface surrounding the opening  14 , the front  15 . The larger section  13  with the opposing surface forms the back  16 , of the base part  11 . The side walls of the two sections  12 ,  13 , which surround the opening  14 , are double-walled in design, and delimit the opening  14  with an inside wall  17 . The section  12  has an outer wall  18  a defined distance from the inner wall  17 , and the section  13  has an outer wall  19 . The outer walls  18 ,  19  are connected with the applicable adjacent segment of the inner wall  17  by crosspieces  20  or  21 . At their adjoining ends, the sections  12 ,  13  are delimited by flat, center walls  22 ,  23 , which connect the outer walls  18 ,  19  with the inner wall  17 , and are additionally connected to one another by ribs at the inner wall  17 . A groove  24  is formed by a separation between the center walls  22 ,  23 . 
     The larger section  13  projects beyond the smaller section  12  on all sides, thereby forming a bearing flange  25 , on which the fastening clip  10  can be braced in the direction of the axis A. Located on the outside of the section  12 , parallel to the flange  25 , is a rib  26 , which serves to define the installation position of the fastening clip  10  and to prevent incorrect installation. The rib  26  extends to a plane generally co-planar to outer wall  19 . 
     The opening  14  contains a retaining region  28  and an unlocking region  29 . Located opposite one another in the retaining region  28  are two opposed locking fingers  30 , which are attached by one end to the forward end of the inner wall  17  in an elastically resilient way. The locking fingers  30  project inward into the opening  14 , and are inclined toward the axis A in such a way that their spacing decreases from the outside to the inside. The inner ends of the locking fingers  30  form locking teeth  31 , which extend parallel to one another in the longitudinal direction of the opening  14 . The locking fingers  30  and locking teeth  31  terminate approximately in the center of the opening  14  so that the adjoining unlocking region  29  is free of locking teeth. 
     Arranged in the retaining region  29  in the vicinity of the rearward end of the opening  14  is an elastic finger  32 , which is attached to the section of the inner wall  17  that runs in the transverse direction, and which extends into the unlocking region  29 . A sawtooth-shaped locking projection  33  is attached to the finger  32  on the side facing the front  15 ; said locking projection has a ramp surface  34  facing the retaining region  28  and has a locking surface  35  facing the unlocking region  29 . The locking surface  35  delimits the unlocking region  29  with respect to the retaining region  28  and lies in a plane at which the locking fingers  30  and locking teeth  31  also terminate. 
       FIG. 4  shows a component  40  that is meant to be attached using the described fastening clip  10 . In order to join the fastening clip  10  to the component  40 , said component has a receptacle part or doghouse  41  in which the fastening clip  10  can be inserted. The receptacle part  41  consists of a flat plate  42  with a pilot slot  43  that forms a pilot region  44  expanding in a wedge shape toward the pilot opening, a narrow spot formed by retaining projections  45 , and an end region  46  that has a greater width than the narrow spot. A U-shaped wall  47  extends along the outer edge of the plate  42 . The wall  47  is perpendicular to the plate  42  and has a uniform height, so that the plate  42  is located at a constant distance from the component  40 . The wall  47  has two side sections  48 , which are located on two sides of the pilot slot  43  and are oriented parallel to one another. Additionally, a guide rib  49  is arranged parallel to one of the side sections  48  on the top of the plate  42  facing away from the component  40 . 
     In order to connect the fastening clip  10  to the component  40 , said clip is pushed through the lateral opening into the pocket formed by the receptacle part  41 , as shown in  FIG. 5 . The correct position of the fastening clip  10  in the receptacle part  41  is ensured here firstly by the guide rib  49  and the height of the wall  47  of the receptacle part  41 , and secondly by the rib  26  and the thickness of section  12  of the fastening clip  10 . Thus, the collision of the rib  26  with the guide rib  49  prevents installation of the fastening clip  10  in a position that has been rotated by 180°. Moreover, the greater thickness of the section  12  as compared to the height of the wall  47  prevents the section  12  from being inserted in the pocket between the component  40  and the plate  42 . Installation of the fastening clip  10  in a position rotated by 90° from the position in  FIG. 5  is prevented by the fact that the width of the flange  25  is smaller than the width of an end region  36  of the pilot slot  43 , so that the fastening clip  10  cannot find proper support in the receptacle part  41 . Moreover, the fastening clip  10  would not find support at the narrow spot formed by the retaining projections  45 , and would fall out of the receptacle part  41  again. Thus, incorrect installation of the fastening clip  10  is efficaciously prevented. 
     In order to attach the fastening clip  10  to the component  40 , the fastening clip  10 , with its longitudinal side forward, is pushed into the receptacle part  41  as shown in  FIG. 5 . In the process, the pocket of the receptacle part  41  receives the flange  25 , and the edge of the plate  42  delimiting the pilot slot  43  engages in the groove  24 . The outside diameter of the fastening clip  10  measured in the longitudinal direction is somewhat greater in the region of the groove  24  than the narrow spot formed by the retaining projection  45  so that the fastening clip  10  must be forced into the end region  46  of the pilot slot  43  with a certain amount of force and elastic deformation thereof. In the final position shown in  FIG. 5 , the core cross section of the fastening clip  10  in the region of the groove  24  is located entirely within the end region  46 , so that the retaining projections  45  that were forced somewhat apart during installation now spring back to their original position and hold the retaining clip  10  in place in the receptacle part  41 . 
     Once the fastening clip  10  has been joined to the component  40 , the two pieces can be attached to the stud  50  of a support part  51 , as shown in  FIGS. 6 and 7 . The stud  50  is designed as a so-called T-stud head, and the end of its shank is welded to the support part  51  for attachment. The free end of the stud  50  projecting from the support part  51  is provided with a head  52  of larger diameter; the locking teeth  31  of the locking fingers  30  of the fastening clip  10  can brace against the underside of said head. In place of a T-stud, it is also possible to connect another stud, such as a threaded stud, to the fastening clip  10 . 
     During installation, the component  40 , together with the fastening clip  10 , is arranged in front of the stud  50  in such a way that the head  52  of the stud can enter the retaining region  28 . By pressing the component  40  onto the support part  51 , the locking fingers  30  are elastically forced apart by the head  52 , to then spring back to their initial position after the head  52  has slid past the locking teeth  31 . 
     In the final position shown in  FIGS. 6 and 7 , the locking teeth  31  brace against the underside of the head  52  and the shank of the stud  50 , thus holding the fastening clip  10 , and with it the component  40 , firmly on the support part  51 . In this fastening position, the head  52  is located between the locking projection  33  and the inner wall  17 , with the diameter of the head  52  being smaller than the distance between the locking projection  33  and inner wall  17 . The clearance in the longitudinal direction that is thus provided between the fastening clip  10  and the head  52  permits for compensation of dimensional deviations in the installation position between the support part  51  and the component  40 . Dimensional deviations in the transverse direction of the fastening clip  10  can be compensated by a slidability of the fastening clip  10  relative to the receptacle part  41 . 
     In order to release the attachment of the component  40 , this is elastically deformable such that the region with the receptacle part  41  can be pushed in the longitudinal direction of the fastening clip  10  relative to the stud  50  such that the stud  50  reaches the unlocking region  29 , as shown in  FIG. 8 . During this process, the head  52  of the stud  50  slides along the locking teeth  31 , so that they are not damaged. As a result of contact of the head  55  with the ramp surface  34  of the locking projection  33 , moreover, the finger  32  is bent towards the component  40 , so that the head  52  can slide past the locking projection  33 . As soon as the stud  50  and its head  52  are located in the unlocking region  29 , the finger  32  springs back to its original position, so that the locking surface  35  of the locking projection  34  is now opposite the cylindrical lateral surface of the head  52 . As a result of this, the stud  50  cannot be forced back into the retaining region  28 . The stud  50  can be pulled out of the unlocking region  29  unhindered, and thus the component  40  can easily be removed from the support part  51 . Even when the stud  50  is being pulled out, it cannot get back into the retaining region  28 , since the head  52  is prevented herefrom by contact with the end faces of the locking fingers  30 . 
     As the described removal process shows, the retention force of the locking fingers  30  need not be overcome during release, and there is no danger of damage to the locking teeth  31 . The fastening clip  10  can thus be used again, with the same level of retention forces being achieved as before. The use of the fastening clip according to the invention is not restricted to the fastener described. The fastening clip can be used in all fastening arrangements in which movability is provided for displacement of the stud out of the retaining region into the unlocking region. 
     The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the invention, and all such modifications are intended to be included within the scope of the invention.