Abstract:
The invention is based on a wiper blade ( 12 ) with an elongated, spring-elastic carrier element ( 36 ) which is pre-curved concavely with respect to a vehicle window ( 22 ) and has at least one spring rail, and with a wiper strip ( 24 ) which is held by the carrier element ( 36 ), wherein the wiper blade ( 24 ) is secured relative to the carrier element ( 36 ) by an end cap ( 44 ) at least near to one end in the longitudinal direction ( 20 ), which end cap ( 44 ) has, on one longitudinal side, an opening which can be closed off by a flap ( 46 ) which can pivot about a pivoting axis ( 84 ) running in the longitudinal direction ( 20 ) into an open position and into a closed position. It is proposed that securing means ( 56, 58, 66 ) be provided on the end cap ( 44 ) or the flap ( 46 ), which securing means ( 56, 58, 66 ) can be moved by the activation of the flap ( 46 ) with the wiper blade ( 24 ) or with an element ( 120, 124, 128, 132, 136, 142 ) connected thereto into an operative connection or out of an operative connection, wherein the securing means ( 56, 58 ) are supported in the longitudinal direction ( 20 ) on the carrier element ( 36 ) or an element ( 52 ) which is permanently connected thereto, and said securing means ( 56, 58 ) and/or become detached therefrom.

Description:
BACKGROUND OF THE INVENTION 
     The invention is based on a wiper blade. 
     WO 2008/020003 discloses a wiper blade having an elongated, spring-elastic carrier element which is pre-curved concavely with respect to a vehicle window and which has at least one spring rail, and having a wiper strip which is held in a replaceable fashion by the carrier element. The wiper strip is permanently connected at one end to a thickened portion by means of which the wiper strip can be secured relative to the carrier element. This is done by virtue of the fact that the thickened portion can be laid on one end side of the spring rail or on a bridge which connects two spring rails, serving as a carrier element, to one another. In this position, the wiper strip is secured relative to the carrier element by an end cap. The latter can engage over the thickened portion and the bridge and secure them in position by releasable latching means. In the case of disassembly of the wiper strip of the wiper blade the latching means are released, with the result that after the removal of the end cap the wiper strip can be pulled out of the carrier element. 
     The thickened portion can be implemented by means of different configuration elements, for example by means of separate components which are connected to the wiper strip, or integrally formed-on parts which bring about a local increase in the cross-section of the cross-sectional profile of the wiper strip at the end of the wiper strip. The first-mentioned measures include clamps made of metal or plastic or a combination of these materials, for example plastic-coated metal clamps or bracket-shaped plastic parts which are attached to the wiper strip by metal clamps. In the simplest case, staples are sufficient, the limbs of said staples being pressed, while pointing towards the wiper lip, by the upper part of the head strip and being bent over toward the web which runs between the longitudinal grooves for the spring rails. 
     Another possibility is that the staple runs in the longitudinal direction of the wiper strip, while its limbs penetrate the web between the longitudinal grooves transversely with respect to the longitudinal direction and are bent over inward on the opposite side of the web. If the thickened portion is integrally formed onto the wiper strip, it can entirely or partially fill the longitudinal grooves in the end region thereof. In addition, said thickened portion can protrude as a bead or projection beyond the normal cross-sectional profile of the wiper strip. These may be integrally injection-molded-on or extruded-on parts of the wiper strip which are composed of the same material or of similar materials. Basically it is also possible for these parts to be connected as separate parts by bonding, vulcanizing or welding to the wiper strip. 
     According to one configuration of the invention, an opening which can be opened and closed is provided on at least one end cap. A flap which closes off the opening is used for this purpose. The flap is connected to the cap via a film joint whose pivoting axis runs in a longitudinal direction of the wiper blade. In the closed state, the flap latches with a latching edge on a connecting web of the end cap, wherein the end side of the flap, which faces the end of the wiper blade, bears with a fin on the facing end side of the bridge of the carrier element, with the result that the carrier element is secured relative to the wiper strip with the spring rails by means of the end cap. The external contour of the closed flap finishes flush with the face against which there is a flow or the throat of the end cap, with the result that no wind noises are produced at the end cap even in the case of high speed vehicles. 
     DE 10 2004 051 467 A1 discloses a wiper blade. Its carrier element comprises two spring rails which run parallel to one another and which are connected to one another at their ends by a bridge. In order to accommodate a wiper strip, the spring rails form a longitudinal gap, with the result that the wiper strip can be threaded onto the carrier element in the longitudinal direction. The wiper strip is secured in the longitudinal direction relative to the carrier element by end caps. The latter have an element with a mandrel which is pressed into a head strip of the wiper strip at the end of the mounting process. In the mounted state, the mandrel bears against the end side of the bridge which faces away from the end of the wiper strip. In one exemplary embodiment, the mandrel is located on a spring tongue which is pressed against the head strip by a flap with an eccentric. The pivoting axis of the flap runs transversely with respect to the longitudinal direction of the wiper blade. In another embodiment, the mandrel is arranged directly on the flap, wherein the pivoting axis of the flap is provided in the vicinity of the outer end wall of the end cap. 
     DE 100 25 710 A1 discloses a wiper blade of the flat bar design which has a rubber-elastic wiper strip with a wiper lip. Between the wiper lip and a head strip lateral longitudinal grooves are provided into which two spring rails which are pre-curved concavely with respect to the wiper lip are inserted as a carrier element. Said spring rails are held together by bridges at their ends and by a central connecting element. The bridges have as securing means an integrally formed-on projection which has at its free end at least one projection which is directed toward the head strip. During assembly, the projection is bent against the head strip with the result that the projection engages in the head strip and secures the spring rails in the longitudinal direction relative to the wiper strip. The bridges are finally covered with end caps. 
     A similar wiper blade is known from DE 102006059077. In this context, a securing spring which points in the longitudinal direction and which is attached to the bridge presses with a v-shaped profile, which runs transversely in the longitudinal direction, against a head strip of the wiper strip and secures the latter relative to the carrier element. The pressure on the head strip can be amplified by suitable devices in the end cap, on which devices the securing pin is supported. 
     DE 102 45 693 A1 discloses a wiper blade which has, as a carrier element, two spring rails which run parallel and which are connected to one another at each of their ends by a bridge. In addition, securing means are provided which secure the wiper strip relative to the spring rails. In order to dismount the wiper strip, the securing means can easily be released. They are connected at one end to the bridge and at the other end to the wiper strip via a materially joined connection, a frictionally locking connection and/or a positively locking connection. In one exemplary embodiment, a mandrel engages through a guide bore in the bridge into the wiper strip and is secured in the mounting position by an end cap which latches to the bridge by means of a spring element. The spring element can be released by an element which can be operated externally, with the result that the end cap and the mandrel can be released in order to change the wiper strip. In the mounted state, the end cap is supported by a closed end side pointing to the end of the wiper blade on the assigned end side of the bridge. Another exemplary embodiment shows a securing unit which is fabricated from sheet metal and which is pressed into the wiper strip by a mandrel which is bent with respect to the wiper strip. When the spring rails are mounted, the securing unit is pushed under the bridge and latched between the stop faces and a spring tongue on the bridge. The spring tongue can be pressed into a release position after the removal of the end cap, with the result that the spring rails can be dismounted. 
     SUMMARY OF THE INVENTION 
     According to the invention, securing means are provided on the end cap or the flap, which securing means can be moved, through activation of the flap, into or out of an operative connection with the wiper strip or with an element connected thereto, wherein the securing means are supported in the longitudinal direction on the carrier element or on an element which is permanently connected thereto and/or become detached from said carrier element or an element which is permanently connected thereto. The measures according to the invention permit the wiper strip to be reliably secured in a variety of ways at just one end relative to the carrier element with the result that during the operation of the wiper blade the carrier element cannot move out of the wiper strip. This is particularly advantageous if the securement occurs at one end of the wiper blade which describes a large circular arc during operation and is therefore subject to the relatively large centrifugal force. At the same time, the relative movement over the length of the wiper blade between the wiper strip and the carrier element and which is necessary for unforced bending of the wiper strip in order to be able to follow the different curvatures of the window pane is otherwise not impeded. 
     According to one refinement of the invention, a securing means which runs transversely with respect to the head strip of the wiper strip is provided on the inside of the flap, which securing means presses on the head strip in the closed state of the flap and is supported in the longitudinal direction on a bridge which connects to one another two spring rails which run parallel one next to the other and serve as a carrier element. The securing means act as a pressure element by penetrating a certain amount further into the elastic head strip of the wiper strip. Said securing means can also be embodied as a cutting blade which tapers in a wedge shape toward the head strip and which can cut more deeply into the head strip. 
     In addition, further securing means in the form of supports which are arranged on both longitudinal sides of the head strip and are supported on the carrier element when the flap is closed can be provided on the inside of the flap. 
     In addition, the wiper strip can advantageously have, in the end region of its head strip, a transverse groove into which at least one blocking element which is integrally formed onto the flap engages when the flap closes. The blocking element can also be embodied as a separate component in the form of a bolt which is inserted into the transverse groove during mounting and is then permanently connected to the carrier element. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further advantages will emerge from the following description of the drawing. In the drawing, exemplary embodiments of the invention are illustrated. 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 place them together to form further appropriate combinations. 
       In the drawing: 
         FIG. 1  shows a perspective illustration of a wiper blade, 
         FIG. 2  shows a perspective illustration of a wiper blade end having an end cap with a flap on an enlarged scale, 
         FIG. 3  shows a perspective illustration of a wiper blade end without a spoiler part and without a base part of the end cap, 
         FIG. 4  shows a variant of  FIG. 3 , 
         FIG. 5  and  FIG. 6  show a further variant of  FIG. 3 , 
         FIG. 7  shows a further variant of  FIG. 3 , 
         FIG. 8  shows a variant with a transverse groove in the head strip of the wiper strip, 
         FIG. 9  shows a wiper strip according to  FIG. 7  or  FIG. 8 , 
         FIG. 10  shows a variant of  FIG. 8 , 
         FIG. 11  shows a variant with a spring tongue with a projection, 
         FIG. 12  shows variants of arrangements of the spring tongue according to  FIG. 11 , 
         FIG. 13  shows a variant with securing arms on the inside of an end wall of the end cap, 
         FIG. 14  shows a perspective illustration of an end cap according to  FIG. 13  from below, 
         FIG. 15  shows a cross section through a wiper blade in the region of an end cap, 
         FIG. 16  shows a detail from  FIG. 15  on an enlarged scale in a perspective view, 
         FIG. 17  to  FIG. 19  show a variant with a locking hook on its intermediate floor of the end cap, and 
         FIG. 20  to  FIG. 27  show variants of elements which are attached to the head strip of the wiper strip. 
     
    
    
     DETAILED DESCRIPTION 
     A wiper blade  12  has a spring-elastic carrier element  36  which is elongated in the form of a belt and is in the form of two spring rails running parallel to one another at a distance from one another ( FIG. 1  and  FIG. 3 ). Said spring rails are inserted by their inner edge strips, facing one another, into longitudinal grooves  32  in a head strip  30  of a wiper strip  24 , while their outer edge strips protrude laterally a certain amount from the longitudinal grooves  32 . Between the longitudinal grooves  32  there is a web  34 . Toward a vehicle window  22 , a wiper lip  26  adjoins the head strip  30  via a tilting web  28 , said wiper lip  26  sliding over the vehicle window  22  during a wiping movement in the direction of a double arrow  18 . For this purpose, a wiper arm  10  pushes the wiper blade  12  via a connecting device whose wiper-blade-side part  14  can be connected in an articulated and releasable fashion to the wiper arm  10  while said wiper arm  10  is securely seated in the central region of the wiper blade  12  on the carrier element  36  thereof. At the same time, the wiper arm  10  loads the wiper blade  12  in the direction of the vehicle window  22  with a pressing force  16 . The wiper arm  10  and the vehicle window  22  are indicated by dot-dash lines. During operation, the ends  40 ,  42  of the wiper blade  12  describe circular arcs during a pivoting movement about a wiper shaft (not illustrated) in the direction of the double arrow  18 , wherein the inner end  40  describes an inner circular arc and the outer end  42  describes an outer circular arc. 
     The greatest degree of curvature of the vehicle window  22  is less than the curvature of the still unloaded wiper blade  12  which bears with its two ends  40 ,  42  against the window pane  22  ( FIG. 1 ). Under the pressing force  16 , the wiper blade  12  bears with its wiper lip  26  over its entire length against the window pane  22 . In this context, a tension builds up in the spring-elastic carrier element  36  which is fabricated from metal or plastic, said tension ensuring that the wiper strip  24  or the wiper lip  26  bears satisfactorily over its entire length against the window pane  22 , as well as ensuring that the pressing force is distributed uniformly. 
     On both sides of the wiper-blade-side connecting element  14  there are spoiler parts  38  which adjoin in the longitudinal direction  20  and are guided on the carrier element  36 . End caps  44  are provided at the ends  40 ,  42  of the wiper blade  12 , said end caps  44  likewise being guided on the carrier element  36 , latching thereon and covering the ends of the spoiler parts  38 . The spoiler parts  38  have a flow profile  48 , while the flow profiles of the end caps  44  are characterized by  50 . 
     One of the end caps  44 , preferably that at the outer end  42 , serves to secure the wiper strip  24  relative to the carrier element  36 . Said end cap  44  has a base part  45  whose outwardly pointing end is connected via bars  78  to a part pointing to the spoiler part  38 . In the region of the bars  78 , a flap  46  is mounted so as to be pivotable about a pivoting axis  84  running in the longitudinal direction  20 . The pivoting axis  84  is formed by bearing elements  105  on the flap  46  and by bearing elements  106  on the base part  45 . The bearing elements  105  and  106  are spigots which fit into corresponding bearing bores in the respective other part. 
     The flap  46  closes an opening in the base part  45 . It has a latch  90  on an edge which runs parallel to the pivoting axis  84  at a distance therefrom. In the closed state of the flap  46 , the latch  90  latches in a corresponding cutout  92  in the associated bar  78 . The flap  46  also has, for the purpose of stiffening, and in the region of the latch  90 , a centering fin  88  which in the closed state engages in a groove  80  in the associated bar  78 . On the inside of the flap  46  there are transverse struts  86 , at least one of which is embodied as a securing means in the form of a cutting blade  58 . The latter presses, in the closed state of the flap  46 , on the top side of the head strip  30 , as a result of which the latter is secured in the longitudinal direction  20  with respect to the flap  46 , which is in turn secured relative to the carrier element  36  by the base part  45 . 
     The carrier element  36 , which can basically also be composed of a spring rail which is accommodated in a central longitudinal duct of the head strip  30 , is composed in the illustrated exemplary embodiments of two spring rails which run parallel to one another and are connected to one another at their ends by a bridge  52  by feet  54  of the bridge  52  being attached to the carrier element  36  by suitable means, for example by welding, bonding, riveting or the like. In the closed state of the flap  46 , the securing means  58  bear against the end side of the bridge  52  which faces the spoiler part  38 . The wiper strip  24  is therefore secured in a first direction relative to the carrier element  36  by the securing means  58  of the flap  46 . 
     In addition or alone, securing means  56  may be provided in the form of supports which are supported on both sides of the head strip  30  on the carrier element  36 , and can bear on the feet  54  of the bridge  52  on the same side as the securing means  58 . On the side lying opposite the support, the carrier element  36  is led through guide strips  60 . According to a further embodiment, the supports  56  can have lateral cutting blades  62  which face the head strip  30  and cut into the edge regions of the head strip  30  when the flap  46  closes ( FIGS. 5 and 6 ). 
     In the second direction which is opposed to the first direction, the carrier element  36  is secured to the wiper strip  24  by a further transverse strut  86  of the flap  46  or of the base part  45 , wherein the transverse strut  86  bears on the side of the bridge  52  or the feet thereof  54  lying opposite the securing means  56 ,  58  or bears against the end sides of the carrier element  36 . 
     In a further embodiment, the place of the securing means  58  is taken by securing means  66  in the form of blocking elements which are integrally formed onto the inside of the flap  46  and engage in a transverse groove  64  in the head strip  30 . The latter is therefore secured with respect to the end cap  44 , which for its part latches with the carrier element  36 , for example by means of suitable latching means, on the bridge  52  or in lateral cutouts  140 . 
     In the embodiment according to  FIG. 8 , a fitting bolt  68 , which is attached to the carrier element  36  at attachment points  70  by means of notched pins, rivets, welding points or the like, is located in the transverse groove  64 . The wiper strip  24  is therefore secured directly to the carrier element  36  via the bolt  68 . Said wiper strip  24  can, however, as shown by the embodiment according to  FIG. 10 , also be indirectly secured by a locking block  74  by virtue of the fact that the locking block  74  engages in the transverse groove  64  in the head strip  30 . The locking block  74  is arranged by means of a spring tongue  72  which is integrally formed onto an end wall  82 . A stop  76  which protrudes over the locking block  74  bears against the back of the head strip  30  as soon as the locking block is latched in to the transverse groove  64 . The wiper strip  24  is secured with respect to the carrier element  36  by means of the base part  45  of the end cap  46  which is latched in a conventional fashion to the carrier element  36 . 
     In the embodiment according to  FIG. 11 , the place of the spring tongue  72  with a locking block  74  is taken by a spring tongue  72  with a projection  96 . The spring tongue projects as far as the region of the flap  46  and is pressed against the head strip  30  by its projection  96  when the flap  46  closes, with the result that the projection  96  penetrates a certain amount into the head strip  30  or cuts into it. In  FIG. 11 , the spring tongue  72  is arranged on an edge of the base part  45  which is located on the opening for the flap  46  on the side toward the spoiler part  38 .  FIG. 12  shows variants in which the spring tongue  72  is integrally formed onto one of the longitudinal sides of the base part  45  and is activated by an element of the flap  46  through an opening  97  in an intermediate wall  94 . In the third arrangement the spring tongue  72  is integrally formed onto the end wall  82  of the base part  45  and projects from there into the region of the flap  46 . 
     The configuration according to  FIGS. 13 and 14  shows two securing arms  100  which are integrally formed onto the inside of the end wall  82  of the base part  45  in the longitudinal direction  20 . 
     Said securing arms  100  engage, in the mounted state, a certain amount into the longitudinal groove  32  of the head strip  30  and hook with teeth  102  lying opposite one another at their ends into the web  34  formed between the longitudinal grooves  32 . In addition, a short spigot  104 , which is also directed in the longitudinal direction  20 , penetrates the wiper strip  24  and supports it in a region in which the carrier element  36  is no longer effective. On the inside of the cover wall of the base part  45  there are guide ribs  98  which run approximately parallel to the securing arms  100  and form a lateral guide relative to the bridge  52 , said cover wall forming the flow profile  50 . 
     In the embodiment according to  FIGS. 15 and 16 , the end cap  44  has a longitudinal duct  108  which has a U-shaped cross section and is open towards the carrier element  36 . The longitudinal duct  108  accommodates the head strip  30  which is pushed to the outer end  42  when it is mounted in the longitudinal duct  108  in the longitudinal direction  20 . At the end of the longitudinal duct  108  or in the region of the flap  46 , wedge-shaped pressure elements  110  are integrally formed onto the edges of the longitudinal duct  108 . If the flap  46  is then closed or the wiper strip  24  is then pushed into the longitudinal duct  108  in the longitudinal direction  20 , the head strip  30  is pressed against the carrier element  36  by the wedge-shaped pressure elements  110  and secured in this way. In this context, the wedge-shaped pressure elements  110  generate pressing forces which are directed in the direction of the web  34 . 
     In the embodiment according to  FIG. 17  to  FIG. 19 , the wiper strip is secured relative to the end cap  44  by a hook  114  made of sheet metal. Said hook  114  runs in the longitudinal direction  20  and is cast in an intermediate floor  112  of the end cap  44 . During the mounting of the end cap  44 , it bears against a lateral cutout  140  in the carrier element  36 , while at the same time the end side of the carrier element  36  bears against the inside of the end wall  82  of the end cap  44 . In this position, a bent end  116  of the sheet metal hook  114  is pressed into the head strip  30  through an opening  118  in the flow profile  50 . The wiper strip  24  is therefore secured relative to the carrier element  36  by means of the sheet metal hook  114  of the end cap  44 . The embodiments according to  FIG. 20  to  FIG. 27  are defined by separate elements which are permanently connected to the wiper strip  24  in the region of one end of the head strip  30 . According to  FIG. 20 , such an element is a clamp  120  which embraces the head strip  30  from the back and engages with its limbs in the longitudinal grooves  32 . In the process, teeth  122  penetrate the assigned longitudinal sides of the web  34 . 
     The embodiment according to  FIG. 22  differs from the previously described embodiment in that a clamp  124  embraces the web  34  from the end side and engages with teeth  122  in the web  34 . The embodiment according to  FIG. 23  and  FIG. 24  has filler elements  128  which are inserted into the ends of the longitudinal grooves  32 . Two filler elements  128  which lie opposite one another are connected to one another by an opening  126  in the web  34  with at least one connecting element  130  in the form of a rivet pin, a clip or the like. The embodiment according to  FIG. 25  similar to the embodiment according to  FIG. 22 , but the teeth  122  are missing, with the result that the U-shaped filler element  132  is connected in a materially joined fashion by its limbs  134 , projecting into the longitudinal grooves  32 , to the head strip  30  by means of ultrasonic welding, bonding or the like. 
     The embodiment according to  FIG. 26  shows a sheet metal clamp  136  which embraces the head strip  30  from above. On its longitudinal sides, the clamp  136  has projections  138  which can be pressed laterally into the head strip  30 . In a similar way, in the embodiment according to  FIG. 27  a clamp  142  made of sheet metal embraces the head strip  30  from the back. Said clamp  142  has in its cover wall a window  144  into which a locking hook  146  projects in the longitudinal direction  20 , the bent end  148  of which locking hook  146  is pressed into the head strip  30  during mounting.