Abstract:
The invention relates to a clamping apparatus comprising a base body and two clamping straps which are arranged opposite one another on one side of the base body, are made flexible at least sectionally, extend convexly to one another in a non-clamping state of the clamping apparatus and can be brought into engagement by being pressed together in order thereby to fasten an object located between the clamping straps and the base body to the clamping apparatus by means of a clamping fit.

Description:
TECHNICAL FIELD  
       [0001]     The invention relates to a clamping apparatus comprising a base body and a clamping means by which the base body can be fastened to an object, for example to a flat conductor.  
       BACKGROUND OF THE INVENTION  
       [0002]     Such a clamping apparatus is generally known. In one kind of clamping apparatus, a clamping arm is supported on a side of the base body by means of a complex hinge. The object to be fastened is placed on the base body, the clamping arm is folded over it and the free end of the clamping arm is latched to the base body to achieve a clamping connection of the object between the clamping arm and the base body. In another kind of clamping apparatus, it is a question of a two-part system that includes a base body and a separate clamping part which can be plugged together or placed onto one another and latched to one another, whereby an object arranged between the base body and the clamping part is held in a clamping manner.  
         [0003]     It has proven to be a problem with both types of clamping apparatus that in each case two components which are separate at least originally, namely the base body and the clamping means, have to be joined together to form a complex article. Moreover, the assembly of the hinge described above and the folding over of the clamping means in an automated process is particularly problematic.  
       SUMMARY OF THE INVENTION  
       [0004]     It is the underlying object of the invention to provide a simplified clamping apparatus which can be manufactured at a favorable cost, is easy to handle and can be integrated particularly easily into an automated assembly process.  
         [0005]     A clamping apparatus having the features of claim  1  is provided to satisfy this object.  
         [0006]     The clamping apparatus in accordance with the invention includes a base body and two clamping straps which are arranged opposite one another on one side of the base body, are made flexible at least sectionally, extend convexly to one another in a non-clamping state of the clamping apparatus and can be brought into engagement by being pressed together in order thereby to fasten an object located between the clamping straps and the base body to the clamping apparatus by means of a clamping fit.  
         [0007]     Since the clamping straps extend convexly to one another in the non-clamping state of the clamping apparatus, i.e. have a larger spacing from one another in a middle region of the clamping straps than in the end regions of the clamping straps, an object to be clamped, for example a flat conductor, can easily be inserted into the clamping apparatus between the clamping straps.  
         [0008]     A clamping of the object is achieved by a simple pressing together of the clamping straps. The clamping apparatus can, vice versa, be opened again by pulling the clamping straps apart.  
         [0009]     When the clamping straps are pressed together, they spring out of their convex position into a concave position. In this position, the spacing between the clamping straps is smaller in the region of the clamping strap center than in the region of the clamping strap ends. Due to the concave extent of the clamping straps, they extend over the object inserted into the clamping apparatus and exert a clamping force on said object. The object is thereby secured in the clamping apparatus.  
         [0010]     The pressing together of the clamping straps is a simple translatory movement which can easily be automated. The clamping apparatus in accordance with the invention is therefore particularly well suited for an automated assembly on objects to be clamped, in particular flat conductors such as flexible printed circuits (FPCs), flexible flat cables (FFCs) or extruded flexible circuits (EFCs).  
         [0011]     The clamping apparatus in accordance with the invention can be fastened to all flat conductors available on the market thanks to a corresponding dimensioning of the base body and of the clamping straps, without the flat conductors having to be adapted, i.e. especially designed, for this purpose.  
         [0012]     The clamping apparatus in accordance with the invention can furthermore be provided for different applications such as for the protection of electronic components, e.g. as light emitting diode holders or light emitting diode housings, as plug connectors, or as fastening means, e.g. clip holders, for the fastening of a flat conductor to a carrier or to a chassis.  
         [0013]     Advantageous embodiments of the invention can be seen from the dependent claims, from the description and from the drawing.  
         [0014]     In accordance with an advantageous embodiment of the clamping apparatus in accordance with the invention, the clamping straps can be fixed to one another in the pressed-together state. It is thereby prevented that the pressed-together clamping straps can spring open again on their own. A permanently reliable holding of the object in the clamping apparatus is thus ensured.  
         [0015]     The clamping straps preferably have closing means, in particular latching means, which are made in a respectively complementary manner, for a fixing of the clamping straps in the pressed-together state. This permits a particularly simple latching of the clamping straps in the pressed-together state.  
         [0016]     It is particularly advantageous for the closing means to be made such that, in the fixed state of the clamping straps, they effect a rotation of at least one clamping strap through which an intermediate space between the clamping strap and the base body is reduced and a clamping force is exerted in the direction of the base body. Since the closing means do not only serve for the latching of the clamping straps, but also effect a rotation of the clamping straps in the latched state which is responsible for the clamping force, the closing means satisfy a dual function. This simplifies the design of the clamping apparatus and permits an establishment of the clamping apparatus with a lower economic effort.  
         [0017]     The closing means can extend transversely to the longitudinal extent of the clamping straps and substantially over the total width of the clamping straps. The reliability of the latch connection of the clamping straps is thereby increased in the pressed-together state.  
         [0018]     The closing means of at least one clamping strap preferably has a lower height with respect to the clamping strap in a region remote from the base body than in a region facing the base body. A rotation of at least one clamping strap is thereby achieved in a simple manner such that the edge of the clamping strap facing the base body is deflected in the direction of the base body. This results in a reduction of the gap width of an intermediate space provided between the clamping strap and the base body and thus in the exertion of a clamping force onto an object arranged in this intermediate space.  
         [0019]     In accordance with a further embodiment, each clamping strap is formed by a plurality of respectively planar strap sections which are oriented, at least in the clamping state of the clamping apparatus, substantially at right angles to a surface of the base body. The design of planar strap sections simplifies the manufacture of the clamping apparatus and simultaneously increases its stability. The substantially right-angled orientation of the strap sections to the surface of the base body simplifies the pressing-together and pulling apart of the clamping straps and the springing of the clamping straps from their convex position into their concave position or, vice versa, from their concave position into their convex position. It is generally also possible to make the clamping straps in a round arc shape.  
         [0020]     Each end of the clamping straps is preferably fastened to a support post which is in particular respectively arranged in a corner region of the base body and preferably forms a guide for the object to be fastened to the clamping apparatus. The support posts can thus also satisfy a dual function, namely serving for the support of the clamping straps, on the one hand, and providing a correct alignment of the object to be clamped in the clamping apparatus, on the other hand.  
         [0021]     Strap sections of the clamping straps adjacent to one another and/or the clamping straps and the support posts are advantageously connected to one another in the manner of a film hinge. A flexibility of the clamping straps is achieved in a simple manner by the film hinge-like connection of the individual strap sections to one another or of the clamping straps and the support posts which permits the pressing together of the clamping straps and the exertion of a clamping force onto an object arranged between the clamping straps and the base body. The respective film hinges are preferably formed by a tapering of the clamping strap material transversely to the longitudinal extent of the clamping straps. At the same time, the stability of the clamping apparatus can be increased by a correspondingly strengthened design of the strap sections and/or of the support posts.  
         [0022]     In accordance with a further embodiment, fastening means, in particular clip/spring elements or latching lugs, are provided on the side of the base body remote from the clamping straps for the fastening of the clamping apparatus to a support. The object to be clamped, e.g. a flat conductor, can thereby be fastened in a simple manner, and in particular releasably, to a support or chassis with the aid of the clamping apparatus.  
         [0023]     The base body can have at least one cut-out for an electronic component which is connected to an electrical lead to be fastened to the clamping apparatus. The clamping apparatus can thus form a protective housing for the electronic component which is simple to assemble.  
         [0024]     The clamping straps are advantageously made in one piece with the base body. The clamping apparatus can thus not only be manufactured in a particularly favorable manner, e.g. as an injection molded plastic part, but is also particularly simple to handle. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0025]     The present invention will be described in the following purely by way of example with reference to advantageous embodiments and to the enclosed drawings. There are shown:  
         [0026]      FIG. 1  is an embodiment of the clamping apparatus in accordance with the invention in the non-clamping state;  
         [0027]      FIG. 2  is the clamping apparatus of  FIG. 1  with pressed-together clamping straps;  
         [0028]     FIGS.  3 A-C are a sequence of assembly steps for the fastening of a flat conductor in the clamping apparatus of  FIG. 1 ;  
         [0029]      FIG. 4  is a rear side view of the clamping apparatus of  FIG. 1 ; and  
         [0030]      FIG. 5  is a perspective view of a further embodiment of the clamping apparatus in accordance with the invention. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0031]      FIG. 1  shows a first embodiment of the clamping apparatus  10  in accordance with the invention which is made in one piece and has a plastic material. The clamping apparatus  10  can, for example, be an injection-molded part.  
         [0032]     The clamping apparatus  10  includes a base body  12  which has the shape of a rectangular plate in the embodiment shown. Both sides of the plate are made substantially planar. In a central region of the plate, a substantially rectangular cut-out  13  of the base body  12  is provided whose purpose will be described in more detail in connection with  FIG. 4 .  
         [0033]     On the one side of the base body  12 , which will be called the front side  14  in the following, guide projections  15  are arranged along the longitudinal edges of the base body  12  whose purpose will be described in more detail in connection with  FIG. 3A .  
         [0034]     Furthermore, four support posts  16  are provided at the front side  14 , with each support post  16  being arranged in a corner region of the base body  12  and being oriented substantially at right angles to the front side  14  of the base body  12 .  
         [0035]     Each support body  16  has a projection  17  which extends toward the longitudinal central plane of the base body  12  and which includes a first side  17 ′, which is oriented at right angles to the longitudinal cross-sectional plane of the base body  12  and faces toward the edge of the base body  12 , and a second side  17 ″ which is oriented obliquely to the first side  17 ′ and faces toward the respective support post  16  lying diagonally opposite. The purpose of the projections  17  will be explained in connection with  FIG. 3 A .  
         [0036]     The support posts  16  serve for the support of two clamping straps  18 ,  19  which respectively extend between the corresponding support posts  16  arranged successively in the longitudinal direction at opposite longitudinal sides of the base body  12 . The lower edges of the clamping straps  18 ,  19  have such a spacing to the front side  14  of the base body  12  that the clamping straps  18 ,  19 —as will be explained in connection with  FIG. 3 —can move over an object, e.g. a flat conductor, to be fastened in the clamping apparatus  14 .  
         [0037]     Each clamping strap  18 ,  19  is formed by three strap sections, namely by a central section  20  and two end sections  22 , which adjoin the center section  20  at opposite sides thereof. The end sections  22  are connected to the respective support posts  16  at their ends respectively facing away from the central section  20 .  
         [0038]     Both the central section  20  and the end sections  22  of the clamping straps  18 ,  19  have such a material thickness that they are substantially rigid. The clamping straps  18 ,  19  only have a comparatively low material thickness in the transition regions  24  between the end sections  22  and the central section  20  or the end sections  22  and the respective support posts  16  in order to give the clamping straps  18 ,  19  a certain flexibility. Each transition region  24  thus forms a film hinge.  
         [0039]     The length of the clamping straps  18 ,  19  is larger than the spacing between the support posts  16  at which the clamping straps  18 ,  19  are respectively supported. The clamping straps  18 ,  19  therefore do not extend in a straight line between their respective support posts  16 , but have a curved extent. The clamping straps  18 ,  19  of the embodiment shown in the plan view of the front side  14  do not describe an arc-shaped curvature, but a sequence of straight segments angled with respect to one another which are caused by a multiple angling of the clamping straps  18 ,  19  in the respective film hinge-like transition regions  24 .  
         [0040]      FIG. 1  shows the clamping apparatus in the non-clamping state, i.e. in an open state of the clamping apparatus  10 . In this state, the clamping straps  18 ,  19  are curved convexly outwardly with respect to the center of the base body  12 , i.e. the central sections  20  of the clamping straps  18 ,  19  have a larger spacing from one another than the ends of the clamping straps  18 ,  19  connected to the support posts  16 .  
         [0041]     By pressing the clamping straps  18 ,  19  together, they can be moved out of their convex position into a concave position, i.e. into a closed state of the clamping apparatus  19 , in which the clamping straps  18 ,  19  have a smaller spacing in the region of their central sections  20  than in the region of their ends supported at the support posts  16 , as is shown in  FIG. 2 .  
         [0042]     To press the clamping straps  18 ,  19  together, it is not necessary to exert a force onto the clamping straps  18 ,  19  during the whole deformation of the clamping straps  18 ,  19 . It is rather sufficient to overcome a specific pressure point which approximately marks the border between the convex curvature and the concave curvature of the clamping straps  18 ,  19 . After this pressure point has been overcome, the clamping straps  18 ,  19  automatically spring to the other side of an imaginary plane which extends through the support posts  16  of the respective clamping strap  18 ,  19 .  
         [0043]     The clamping straps  18 ,  19  have closing means for the latching of the clamping straps  18 ,  19  in the pressed-together state for protection against an unintended springing back of a clamping strap or of both clamping straps  18 ,  19 . These closing means are formed by latching means  26 ,  28  which are each provided in the region of the central sections  20  of the clamping straps  18 ,  19 .  
         [0044]     The latching means  26  of the first clamping strap  18  includes a web  30  which extends transversely to the longitudinal extent of the clamping strap  18  and substantially over the whole width of the clamping strap  18 . The web  30  projects from the central section  20  of the clamping strap  18  and extends in the direction of the second clamping strap  19 . At its end facing away from the central section  20 , the web  30  is provided with a wider section  34  such that the latching means  26  of the first clamping section  18  has a mushroom-like or T shape in section, i.e. in the plan view of the front side  14  of the base body.  
         [0045]     The latching means  28  of the first clamping strap  19  likewise extends transversely to the longitudinal extent of the clamping strap  19  and substantially over the whole width of the clamping strap  19 . Starting from the central section  20  of the clamping strap  19 , it furthermore extends in the direction of the first clamping strap  18 . The latching means  28  has a cup-shaped or U-shaped section, with latch hooks  35  being provided at the free ends of the section which each face inwardly, i.e. toward one another.  
         [0046]     As shown in  FIG. 2 , the latching means  26 ,  28  are made complementary to one another such that the latching means  26  of the first clamping strap  18  snaps into the latching means  28  of the second clamping strap  19  in the pressed-together state of the clamping straps  18 ,  19 , such that the latch hooks  35  of the second latching means  28  engage behind the wider section  34  of the first latching means  26 , whereby a latch connection is created between the latching means  26 ,  28  and thus between the clamping straps  18 ,  19 .  
         [0047]     In the lower edge region of the central section  20  of the first clamping strap  18 , a rectangular clamping plate  36  is molded which is oriented at right angles to the central section  20 . In the non-pressed-together state, i.e. in the convex position of the clamping straps  18 ,  19 , the clamping plate  36  thus extends approximately parallel to the front side  14  of the base body  12 . The extent of the clamping plate  36  along the clamping strap  18  approximately corresponds to the length of the central section  20 , whereas its extent in the direction perpendicular to the clamping strap  18  approximately corresponds to the height of the latching means  26  with respect to the central section  20  at its end facing the base body  12 .  
         [0048]     Furthermore, a clamping lug  37  is provided at each end section  22  of the clamping straps  18 ,  19  and extends from a lower edge region of the end sections  22 —starting at right angles from these—in the direction toward the respectively other clamping strap  18 ,  19 . The clamping lugs  37  have a triangular shape such that one edge  37 ′ each of the clamping lugs  37  extends parallel to the longitudinal central axis of the base body  12  in the concave position of the clamping straps  18 ,  19 , i.e. in the non-pressed-together state of the clamping straps  18 ,  19 , with the edges  37 ′ of the end sections  22  of a respective clamping strap  18 ,  19  being aligned with one another. In addition, the edge  36 ′ of the clamping plate  36  facing away from the first clamping strap  18  is also aligned with the edges  37 ′ of the clamping lugs  37  of the first clamping strap.  
         [0049]     In the open state of the clamping apparatus  10 , the clamping plate  36  and the clamping lugs  37  thereby create space for the insertion of an object to be clamped into the clamping apparatus  10 .  
         [0050]     The assembly of the clamping apparatus  10  to a flat conductor  38  will now be explained with reference to  FIG. 3 .  
         [0051]     As can be seen from  FIG. 3A , the flat conductor  38  is initially provided with four lateral cut-outs  40 . The positioning and contour of the cut-outs  40  are matched to the projections  17  of the support posts  16 .  
         [0052]     The flat conductor  38  is inserted into the clamping apparatus  10  between the clamping straps  18 ,  19  located in the convex position and is arranged on the front side  14  of the base body  12  such that the projections  17  of the support posts  16  engage into the cut-outs  40  of the flat conductor  38 . The flat conductor  38  is secured against a movement in the longitudinal direction relative to the clamping apparatus  10  by the projections  17  engaging into the cut-outs  40 . The flat conductor  38  is moreover guided laterally by the guide projections  15  arranged between the support posts  16  along the longitudinal sides of the base body  12 . The guide projections  15  therefore ensure, together with the support posts  16 , a precise alignment of the flat conductor  38  with respect to the clamping apparatus  10 .  
         [0053]     The clamping straps  18 ,  19  are pressed together ( FIG. 3B ) and fixed to one another by the latching means  26 ,  28  ( FIG. 3C ) for the clamping of the flat conductor  38  in the clamping apparatus  10 .  
         [0054]     As indicated by the arrows  44  in  FIG. 3C , the latching of the clamping straps  18 ,  19  effects a rotation of the clamping straps  18 ,  19  such that they exert a clamping force onto the flat conductor  38  by which the flat conductor  38  is fixed by means of a clamping seat in the clamping apparatus  10 . The rotation of the clamping straps  18 ,  19  is achieved by a special design of the latching means  26 ,  28 .  
         [0055]     As can be recognized in  FIG. 3B , the latching means  26 ,  28  have a lower height with respect to the respective clamping strap  18 ,  19  in their region remote from the base body  12  than in their region facing the base body  12 . This increasing height of the latching means  26 ,  28  in the direction of the base body effects a tilting of the central sections  20  of the clamping straps  18 ,  19  on the latching of the latching means  26 ,  28  such that the edges of the central sections  20  facing away from the housing  12  are pulled together and the edges of the central sections  20  of the clamping straps  18 ,  19  facing the base body  12  are pressed apart.  
         [0056]     This tilting of the central sections  20  has the result that the edges of the clamping straps  18 ,  19  facing the base body  12  are deflected in the direction of the base body  12 . At the same time, the tilting of the central sections  20  effects a tilting of the clamping plate  36  provided at the central section  20  of the first clamping strap  18  and of the clamping lugs  37  provided at the end sections  22  of the clamping straps  18 ,  19 .  
         [0057]     The result is that the regions of the clamping plate  36  and the clamping lugs  37  facing away from their respective clamping straps  18 ,  19  are pressed onto the flat conductors  38  to be clamped by the tilting of the central sections  20  and the rotation caused by this of the clamping straps  18 ,  19  in the direction of the base body  12 . The flat conductor  38  is thereby securely held in the clamping apparatus  10 .  
         [0058]      FIG. 4  shows the rear side  46  of the clamping apparatus  10  now fastened to the flat conductor  38 . A light emitting diode  48  connected to the flat conductor  38  is arranged in the cut-out  13  of the base body  12 . Four latching lugs  50  are furthermore provided on the rear side  46  of the base body  12 , are arranged in the corner regions of the base body  12  and extend substantially at right angles to the rear side  46  of the base body  12 . The latching lugs  50  serve for the fastening of a cover (not shown) to the base body  12  by which the light emitting diode  48  can be protected against external influences.  
         [0059]     In  FIG. 5 , a further embodiment of the clamping apparatus  10  in accordance with the invention is shown which only differs from the first embodiments shown in FIGS.  1  to  4  in that the base body  12  does not have any cut-out  13  and in that, instead of latching lugs  50 , a centrally arranged clip/spring element  52  and two additional support spring elements  54  are provided at the rear side  46  of the base body  12  through which the clamping apparatus  10  can be fastened to a correspondingly formed support or chassis. The clamping apparatus  10  shown in  FIG. 5  thus permits a fast and simple assembly of a flat conductor to the support or chassis.  
         [0060]     In both the first and second embodiments of the clamping apparatus  10 , the fastening of the flat conductor  38  to the clamping apparatus  10  is easily releasable: the clamping straps  18 ,  19  only have to be pulled apart and the flat conductor  38  removed from the clamping apparatus  10 .