Abstract:
The invention relates to a wiper blade device comprising at least one spring strip ( 10 ) and at least one end sealing unit ( 12 ). According to the invention, in order to fix the spring strip ( 10 ), the end sealing unit ( 12 ) has at least one detent element ( 18 ) which is rendered flexible by means of an inner cavity ( 14 ) in an element ( 16 ) of said end sealing unit ( 12 ).

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The invention starts from a wiper blade device. 
         [0002]    A wiper blade device of a wiper blade for use on a motor vehicle is already known, comprising at least one spring strip and two end termination units. The end termination units are arranged at two ends of the spring strip. 
       SUMMARY OF THE INVENTION 
       [0003]    The invention starts from a wiper blade device having at least one spring strip and at least one end termination unit. 
         [0004]    It is proposed that, in order to fasten the spring strip, the end termination unit has at least one latching element, which is created from an element of the end termination unit by means of an inner aperture. The term “spring strip” is intended, in particular, to mean a component part which has at least one extent that can be changed elastically in a normal operating state by at least 10%, in particular by at least 20%, preferably by at least 30%, and particularly advantageously by at least 50%, and that, in particular, produces a counterforce dependent on a change in the extent, which counterforce counteracts the change. In this context, the term “extent” of an element is intended, in particular, to mean a maximum distance between two points of a perpendicular projection of the element onto a plane. The spring strip is preferably of integral design. The term “integral” is intended, in particular, to mean materially connected, e.g. by means of a welding process and/or an adhesive bonding process etc., and particularly advantageously to mean formed on, as by being produced from a single molding and/or by being produced in a single- or multi-component injection molding process. The spring strip is preferably of elongate design. The spring strip is preferably composed at least partially of spring steel. In an unloaded state, the spring strip preferably has essentially the shape of a bent bar and, as a particularly advantageous possibility, of a flattened bent bar. As a particularly advantageous possibility, a curvature of the spring strip along a longitudinal extent in an unloaded state is greater than a curvature of a vehicle surface of a motor vehicle, in particular of a vehicle window over which the spring strip is guided in at least one operating state. The spring strip preferably has a latching element, in particular an aperture, which is in operative connection with at least one of the latching elements of the end termination unit in an assembled state. Here and below, the term “aperture” is intended, in particular, to mean an aperture in the material of a component extending, in particular, from a first surface of the component to an opposite second surface of the component. 
         [0005]    In this context, the term “end termination unit” is intended, in particular, to mean a unit which is provided for the purpose of being fastened on one end of the spring strip. In particular, the end termination unit is provided for the purpose of providing an end termination for a wiper blade comprising the wiper blade device in an assembled state. The end termination unit is preferably formed at least partially by a plastic. The end termination unit is preferably designed as an end cap, which engages around part of the spring strip, especially in at least one assembled state. The wiper blade device preferably comprises just two end termination units, one for each end of the spring strip. The term “inner aperture” is intended, in particular, to mean an aperture which, during the notional insertion of a bar of infinite length and of any thickness in a direction of introduction, prevents removal of the bar perpendicularly to the direction of introduction. The term “latching element” is intended, in particular, to mean an element which is provided for the purpose of producing a latching connection in interaction with a further latching element. The latching element is preferably embodied as a latching hook which, in particular, has a partial area that is moved in a direction perpendicular to the spring strip during a latching operation and/or changes an extent in a direction perpendicular to the spring strip. In this context, a direction “perpendicular to the spring strip” is intended, in particular, to mean a direction perpendicular to a longitudinal extent of the spring strip. In this context, “latching element created from an element” is intended, in particular, to mean a latching element which is formed from the element by means of an aperture, in particular the inner aperture. An elastically deflectable region is preferably created from the element by means of the inner aperture. 
         [0006]    By means of such an embodiment, it is advantageously possible to provide a stable end termination unit having a latching element in a manner which is simple in terms of design. Moreover, simple and convenient mounting of the end termination unit on the spring strip is made possible. 
         [0007]    In a preferred embodiment of the invention, it is proposed that the end termination unit has a panel that forms the element. In this context, the term “panel” of the end termination unit is intended, in particular, to mean a component part which extends from one side region of the end termination unit to an opposite side region of the end termination unit. In this context, a “side region of the end termination unit” is intended, in particular, to mean a spatial region of the end termination unit which is arranged next to the spring strip in an assembled state. Here, the statement that a spatial region is arranged “next to the spring strip” is intended, in particular, to mean that an infinite extension of the spring strip in the direction of an axis of curvature intersects the spatial region. The term “axis of curvature” of the spring strip is intended, in particular, to mean an axis which is perpendicular to an arbitrary surface normal of a largest smooth surface of the spring strip. The panel is preferably an intermediate panel of the end termination unit. It is thereby possible to increase the stability of the end termination unit. 
         [0008]    In a particularly preferred embodiment of the invention, it is proposed that a partial area of the element is provided for the purpose of being twisted as the spring strip is mounted on the end termination unit. Any twisting of the partial area is preferably reversible. It is thereby possible to produce an advantageously large restoring force for the latching element. 
         [0009]    If the element is formed integrally on the end termination unit, advantageously simple production of the end termination unit with the element is made possible. The end termination unit is preferably produced together with the element as a single molding. The latching element is preferably cut out of the element. 
         [0010]    It is furthermore proposed that the spring strip has at least one latching aperture for fastening the end termination unit. The term “latching aperture” is intended, in particular, to mean an aperture which interacts with a latching element, preferably a latching hook, to form a latching connection. The latching aperture is preferably designed as an inner aperture. It is thereby possible to enable an advantageously simple and low-cost design of the spring strip. 
         [0011]    In another embodiment of the invention, it is proposed that the wiper blade device comprises a wiper strip support, which has a receiving region for holding a wiper strip. A “wiper strip” is intended, in particular, to mean a unit which has a wiper lip and a holding region for holding the wiper lip on a wiper strip support. In this context, the term “wiper lip” is intended to mean an element of the wiper blade device which is moved over the vehicle surface, in particular the vehicle window, during operation of the wiper blade device, preferably touching the surface during a complete movement and, as a particularly advantageous possibility, being pressed as uniformly as possible against the vehicle surface, in particular by the spring strip. The wiper lip is preferably of integral design and is preferably composed of a natural rubber and, as a particularly advantageous possibility, of a synthetic rubber. The term “wiper strip support” is intended, in particular, to mean a unit which is provided for the purpose of fastening the wiper strip on the spring strip. The wiper strip support is preferably distinct from a spring strip and is designed as a separate component. The wiper strip support is preferably composed at least partially of rubber and/or of an at least partially flexible plastic. The receiving region is preferably provided for the purpose of receiving and fastening the holding region of the wiper strip. It is thereby possible to provide secure retention of the wiper strip on the spring strip. If the wiper strip support additionally has a receiving region for the purpose of retaining a spoiler unit, it is furthermore also possible to achieve secure retention of the spoiler unit on the spring strip. In this context, the term “spoiler unit” is intended, in particular, to mean a unit which is provided for the purpose of deflecting a relative wind acting on the wiper blade device and/or of using said wind to press the wiper lip onto the vehicle surface. The spoiler unit is preferably composed at least partially of rubber and/or of an at least partially flexible plastic. 
         [0012]    It is furthermore proposed that the end termination unit has a receiving region for the wiper strip, continuing the receiving region of the wiper strip support in an assembled state. It is thereby advantageously possible to achieve secure retention of the wiper strip, especially in an end region of the wiper blade. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    Further advantages will become apparent from the following description of the drawing. The drawing shows an illustrative embodiment of the invention. The drawing, the description and the claims contain numerous features in combination. A person skilled in the art will expediently also consider the features individually and combine them into worthwhile further combinations. 
           [0014]    In the drawing: 
           [0015]      FIG. 1  shows a wiper blade having a wiper blade device in a schematic illustration, 
           [0016]      FIG. 2  shows the wiper blade device in a section along a line II-II in  FIG. 1 , 
           [0017]      FIG. 3  shows the end termination unit of the wiper blade device in a sectional view, 
           [0018]      FIG. 4  shows the end termination unit and a spring strip of the wiper blade device in an isometric sectional view obliquely from below, 
           [0019]      FIG. 5  shows the spring strip in a plan view, 
           [0020]      FIG. 6  shows the end termination unit and the spring strip in another sectional view, 
           [0021]      FIG. 7  shows the end termination unit, the spring strip and a wiper strip support in an isometric sectional view obliquely from below, and 
           [0022]      FIG. 8  shows the wiper blade device in a sectional view along a line VIII-VIII in  FIG. 2 . 
       
    
    
     DETAILED DESCRIPTION 
       [0023]      FIG. 1  shows schematically a wiper blade  34  having a wiper blade device according to the invention. The wiper blade  34  has an adapter  36 , which is provided for mounting the wiper blade  34  on a wiper arm  38 , depicted in dashed lines, of a window wiper system of a motor vehicle. 
         [0024]      FIG. 2  shows the wiper blade device in a sectional view along a line II-II in  FIG. 1 . The wiper blade device comprises a spring strip  10  of spring steel extended lengthwise in the form of a strip and curved. The wiper blade device furthermore has a wiper strip support  26  composed of a flexible plastic, a wiper strip  30  composed of a synthetic rubber, and a spoiler unit  40  composed of a partially flexible plastic. As can be seen from  FIG. 1 , the wiper strip support  26 , the wiper strip  30  and the spoiler unit  40  are of elongate design and are arranged parallel to the spring strip  10  in an assembled state. The spring strip  10  is provided for the purpose of pressing a wiper lip  42  of the wiper strip  30  in a largely uniform manner against a surface to be wiped during operation of the window wiper system. For this purpose, a curvature of the spring strip  10  is designed in such a way that, in an unloaded state, it is greater than a maximum curvature occurring on the surface to be wiped. The wiper strip support  26  is provided for the purpose of connecting the wiper strip  30  securely to the spring strip  10  and transmitting any side forces which occur during wiping from the wiper strip  30  to the spring strip  10 . The spoiler unit  40  ensures an increased contact pressure of the wiper blade  34  on the surface and prevents the wiper blade  34  from lifting off from the surface owing to the relative wind when the motor vehicle is moving quickly. The wiper blade  34  is closed off at both ends by an end termination unit  12  of the wiper blade device. In this arrangement, the end termination unit  12 , which is designed as an end cap, in each case receives end regions of the spring strip  10 , of the wiper strip support  26  and of the spoiler unit  40  (cf.  FIG. 8 ). 
         [0025]    According to  FIG. 2 , the wiper strip support  26  has an at least substantially H-shaped form when viewed in cross section. When viewed in cross section, ends of the wiper strip support  26  are bent around to form receiving regions  28 ,  44  and holding strips  46 . Receiving region  28  is provided to receive a holding element  48  of the wiper strip  30 . Receiving region  44  is provided to receive the spring strip  10 . The holding strips  46  are provided for holding the spoiler unit  40 . Receiving region  28  is formed on a part of the H-shaped cross section of the wiper strip support  26  which faces the wiper strip  30 . When viewed in cross section, lower H legs  50  of the wiper strip support  26  which face the wiper strip  30  are bent around toward one another. In an end region, the lower H legs  50  of the wiper strip support  26  are aligned parallel to one another and parallel to an H beam  52 . A cavity open in the direction of the wiper strip  30  is thereby formed, into which cavity the holding element  48  of the wiper strip  30  fits positively. Receiving region  44  and the holding strips  46  are formed on a part of the H-shaped cross section of the wiper strip support  26  which faces the spoiler unit  40 . From the H beam  52 , the upper H legs  54 , which face the spoiler unit  40 , initially extend outward on both sides parallel to the H beam  52  and are then bent over at right angles in a direction toward the spoiler unit  40 . After covering a distance corresponding to the thickness of the spring strip  10 , the upper H legs  54  are once again bent over at right angles, more specifically toward one another. After covering a further distance, the upper H legs  54  are once again redirected through 90° in a direction away from the H beam  52 . After covering a further distance, the upper H legs  54  are bent over outward at right angles in a direction away from a center of gravity of the area of the cross section of the wiper strip support  26 . A cavity open toward the spoiler unit  40  is formed directly above the H beam  52 , into which cavity the spring strip  10  fits positively. The folded-over ends of the upper H legs  54  form the holding strips  46 , which engage in corresponding holding grooves  56  of the spoiler unit  40 . 
         [0026]    When viewed in cross section, the spoiler unit  40  has at least substantially the form of an isosceles triangle (cf.  FIG. 2 ). Triangle sides  58  of the triangle are extended beyond a base side  60  of the triangle and there have the holding grooves  56 . In a region of the holding grooves  56 , the spoiler unit  40  is composed of a harder plastic in comparison with the remaining regions of the spoiler unit  40 . It is thereby possible to ensure secure retention of the holding grooves  56  on the holding strips  46  of the wiper strip support  26 . There is furthermore the possibility of simplifying the pushing of the spoiler unit  40  onto the wiper strip support  26  during assembly of the wiper blade  34 . To improve the wind guiding properties of the triangle sides  58 , they have a slightly concave curvature when viewed from the outside. 
         [0027]      FIG. 3  shows the end termination unit  12  in an unassembled state in a sectional view from the side. The end termination unit  12  is composed of an at least partially flexible plastic. For fastening the spring strip  10 , the end termination unit  12  has a latching element  18  created from an element  16  by means of an inner aperture  14 . In this case, the element  16  is formed by a panel  20 , more specifically by an intermediate panel of the end termination unit  12 . The element  16  is formed integrally on the end termination unit  12 . When viewed perpendicularly to a principal plane of extent of the element  16 , the inner aperture  14  is at least substantially U-shaped (cf.  FIG. 4 ). In an assembled state, ends of the U-shaped inner aperture  14  point in the direction of a center of gravity of the spring strip  10 . The element  16  comprises a partial area  22  which is provided for the purpose of being twisted as the spring strip  10  is mounted on the end termination unit  12 . The partial area  22  is arranged on two ends of the U-shaped inner aperture  14 . Twisting the partial area  22  produces a restoring force on the latching element  18 . In a direction away from the partial area  22 , on a side provided for mounting the wiper strip  30 , the latching element  18  is thickened, giving rise to a latching surface  62  which faces one end of the spring strip  10  in an assembled state. A surface normal of the latching surface  62  is substantially parallel to a principal plane of extent of the spring strip  10  in an end region. On a side facing away from the latching surface  62 , the latching element  18  has a run-on bevel  63 . In an assembled state, the run-on bevel  63  has a shallower angle to the principal plane of extent of the spring strip  10  in a first and a third partial area in the end region than in a second partial area situated between the first and the third partial area. On a side which faces away from the wiper strip  30  in an assembled state, the element  16  is of flat design. 
         [0028]      FIG. 4  shows the end termination unit  12  with the spring strip  10  mounted in an isometric sectional view obliquely from below, wherein the wiper strip support  26 , the wiper strip  30  and the spoiler unit  40  are not shown in  FIG. 4  for the sake of greater clarity. Once the latching connection has been established, the latching element  18  engages in a latching aperture  24  in the spring strip  10  (cf.  FIG. 5 ). As the spring strip  10  is introduced into the end termination unit  12 , partial area  22  of the element  16  is twisted. Once the spring strip  10  has been pushed in far enough, the latching element  18  latches into the latching aperture  24 . The spring strip  10  is prevented from being pulled out since the latching surface  62  of the latching element  18  interacts with a corresponding surface bounding the latching aperture  24  and forms a stop once the latching connection has been established. In this way, it is possible to achieve reliable latching of the end termination unit  12  with the wiper strip  10 . 
         [0029]      FIG. 6  shows the end termination unit  12  with the spring strip  10  mounted in another sectional view, wherein the wiper strip support  26 , the wiper strip  30  and the spoiler unit  40  are not shown in  FIG. 6  for the sake of greater clarity. A position of the spring strip  10  relative to the end termination unit  12  perpendicular to the principal plane of extent of the element  16  is defined by holding webs  64 . The holding webs  64  are formed integrally on the end termination unit  12 . To facilitate mounting the spring strip  10  on the end termination unit  12 , the holding webs  64  each have a run-on bevel  66  on a side facing the center of gravity of the spring strip  10 . 
         [0030]      FIG. 7  shows the end termination unit  12  with the spring strip  10  mounted and the wiper strip support  26  mounted in an isometric sectional view obliquely from below, wherein the wiper strip  30  and the spoiler unit  40  are not shown in  FIG. 7  for the sake of greater clarity. The end termination unit  12  has a receiving region  32  for the wiper strip  30 , which region continues the receiving region  28  of the wiper strip support  26 , once the latching connection has been established. It is thereby possible to ensure secure retention of the wiper strip  30  in an end region of the wiper blade  34  too. 
         [0031]      FIG. 8  shows the wiper blade device in a sectional view along a line VIII-VIII in  FIG. 2 . A position of the spoiler unit  40  parallel to the spring strip  10  is defined by abutment of the spoiler unit  40  against an end face  68  of the element  16 , which face faces the spoiler unit  40 . In an inner region, the end termination unit  12  is shaped in such a way that the wiper strip support  26  with the spoiler unit  40  mounted thereon fits positively into the end termination unit  12  (cf.  FIG. 2 ). Use can be made here, in particular, of additional spacer webs of the kind indicated in  FIGS. 2 and 8 , in particular, by spacings shown between the end termination unit  12  and the wiper strip support  26  and between the end termination unit  12  and the spoiler unit  40 . The spacer webs can be provided, in particular, to compensate for manufacturing and/or assembly tolerances.