Patent Publication Number: US-2016221539-A1

Title: Wiper lip for a windshield wiper device

Description:
BACKGROUND OF THE INVENTION 
     The invention relates to a windshield wiper device for a vehicle, in particular a motor vehicle, furthermore in particular a wiper lip for a windshield wiper device. 
     Windshield wiper devices typically have a wiper arm or wiper lever, wherein a wiper blade to which a wiper lip is secured is moved on the windshield of a motor vehicle. The wiper arm is moved alternately between a first turning position and a second turning position. To this end, the wiper arm is connected to a wiper motor by means of the drive shaft. In particular on windshields with great changes of curvature, the wiper blade with the wiper lip easily loses contact with the windshield. In particular with highly curved windshields, this may lead to unwiped wiping regions or to the formation of haze. 
     In windshield wiper devices known from the prior art, during the reversal of the wiper arm in the turning positions, there is often a noise which, in particular depending on the motor vehicle and/or a driver situation of the motor vehicle, is found to be disruptive. This noise is in particular caused by the wiper lip being raised first when the movement direction of the wiper arm or the wiper blade is reversed, wherein the wiper arm is urged away from the windshield and subsequently folds over in the other direction. During the folding, the wiper arm together with the wiper blade is accelerated in the direction of the windshield. In this instance, the wiper blade moves in the direction of the windshield and is then abruptly braked. As a result of the acceleration and the braking, an impact is produced against the windshield, which causes the noise. There is therefore a requirement to further improve windshield wiper devices, in particular to prevent or at least reduce noises of the windshield wiper device. 
     SUMMARY OF THE INVENTION 
     In the improvement of windshield wiper devices, there are a plurality of peripheral conditions which should be taken into account. These include the complexity in terms of the production or the production costs, the material costs, but also the properties of the windshield wiper device, in particular the function under a variety of conditions and the service-life under a large number of conditions. It should be taken into account for wiper devices for vehicles that the cost pressure constantly increases and that the vehicles can be used in a large number of climatic conditions so that, for example, extreme temperature values occur permanently and/or with large fluctuations. 
     An object of the present invention is to provide a wiper lip by means of which at least one or more of the above-mentioned disadvantages is/are reduced or substantially do/does not occur. 
     According to embodiments of the present invention, there is provided a wiper lip which is adapted to a windshield wiper device comprising a wiper blade with an elongate upper portion and an elongate lower portion, which are constructed so as to be at least partially bendable. Furthermore, the windshield wiper device to which the wiper lip is adapted has a plurality of connection elements which are for connecting the upper portion and the lower portion, and which are spaced apart from each other over a longitudinal extent of the wiper blade. Furthermore, the connection elements are configured to enable a movement of the upper portion and the lower portion relative to each other with a movement component over a longitudinal extent of the wiper blade. The windshield wiper device is adapted to a vehicle, in particular a motor vehicle. The wiper blade is configured so that the rigidity of the wiper lip is higher in the wiping direction than the rigidity of the wiper lip perpendicularly relative to the wiping direction. 
     According to another embodiment of the invention, a windshield wiper device is provided for a vehicle, in particular a motor vehicle. The windshield wiper device comprises an elongate upper portion which is constructed so as to be at least partially bendable, an elongate lower portion which is constructed to be at least partially bendable and a plurality of connection elements for connecting the upper portion and the lower portion. The connection elements are spaced apart from each other over a longitudinal extent of the wiper blade and configured in order to enable a movement of the upper portion and the lower portion relative to each other with a movement component over a longitudinal extent of the wiper blade. Furthermore, the windshield wiper device comprises a wiper lip according to the embodiments described herein. 
     Preferred embodiments and particular aspects of the invention will be appreciated from the dependent claims, the drawings and the present description. 
     According to the embodiments described herein, Fin-Ray windshield wiper devices can be produced for vehicle windshields in a particularly advantageous manner and/or can be produced for a plurality of different fields of application. The present embodiments of the windshield wiper device with the wiper lip according to the embodiments described herein enable a particularly good adaptation to the curvature of a windshield. This ensures particularly good and precise wiping of the windshield. Regions of the windshield which are not wiped and a formation of haze on the windshield can be extensively avoided. The structural configuration of the wiper lip described herein enables an extensively uniform pressing pressure of the wiper lip on the windshield so that a high wiping quality is provided and a noise, in particular with a reversal of the movement direction of the wiper arm or the wiper blade in a turning position is prevented or at least reduced. 
     According to embodiments of the disclosure which can be combined with other embodiments described herein, the wiper lip comprises a base region and a wiper region, wherein the base region is configured, when the wiper lip comes into contact with a windshield and the spacing between the wiper blade and the windshield is reduced, to provide a constant pressing force which acts substantially perpendicularly relative to the wiping direction. Consequently, a folding-over of the wiper lip, as known from the prior art, can be reduced or substantially prevented and a noise, in particular in the event of a reversal of the movement direction of the wiper arm or the wiper blade in a turning position can be reduced. 
     According to embodiments of the disclosure which can be combined with other embodiments described herein, the wiper region has a pointed end and a wide end, wherein a wiper edge is arranged at the pointed end of the wiper region, wherein the base region of the wiper lip is arranged at the wide end of the wiper region, and wherein the base region of the wiper lip is wider than the wide end of the wiper region. It is thereby possible for a wiper lip to be provided which has a higher rigidity in the wiping direction than perpendicularly relative to the wiping direction, whereby a folding-over of the wiper lip, as known from the prior art, can be reduced or can be substantially prevented. 
     According to embodiments of the disclosure which can be combined with other embodiments described herein, the base region of the wiper lip has a recess, wherein the recess is arranged above the wide end of the wiper region. Via the sizing of the recess, a constant pressing pressure can be adjusted between the wiper lip and the windshield. 
     According to embodiments of the disclosure which can be combined with other embodiments described herein, the width of the recess in the base region of the wiper lip is greater than the width of the wide end of the wiper region. Via the relationship of the width B W  of the wide end of the wiper region with respect to the width of the recess in the base region, the pressing pressure between the wiper lip and windshield can be adjusted. 
     According to embodiments of the disclosure which can be combined with other embodiments described herein, the wiper edge of the wiper lip comprises an angle of from 60° to 120°, in particular 90°. Consequently, a wiper lip with a particularly high wiping quality is provided. 
     According to embodiments of the disclosure which can be combined with other embodiments described herein, the recess comprises a depth of from 1 mm to 3 mm. Via the depth of the recess, the pressing pressure between the wiper lip and the windshield can be adjusted. 
     According to embodiments of the disclosure which can be combined with other embodiments described herein, the wiper lip is of a material from the group comprising: TPE (thermoplastic elastomer), in particular TPE-S, TPE-O, TPE-U, TPE-A, TPE-V, TPE-E; ethylene-propylene-diene rubber (EPDM); polychloroprene and natural rubber. The material selection of the wiper lip enables the adjustment of the physical properties of the wiper lip and further enables production with the injection-molding method, in particular with a dual component injection-molding method. 
     According to embodiments of the disclosure which can be combined with other embodiments described herein, the base region is formed from a first material and the wiper region is formed from a second material. Consequently, a wiper lip which is optimized in terms of its functional material properties can be provided. 
     According to embodiments of the disclosure which can be combined with other embodiments described herein, the wiper lip is produced by means of an extrusion method or an injection-molding method, in particular a dual component injection-molding method. A wiper lip which is cost-effective and simple to produce is thereby provided. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the invention are illustrated in the Figures and are described in greater detail below. In the drawings: 
         FIG. 1  is a schematic illustration of a wiper lip according to embodiments of the disclosure, 
         FIG. 2A  is a schematic illustration of a wiper lip according to embodiments of the disclosure, 
         FIG. 2B  is a schematic illustration of a wiper lip according to embodiments of the disclosure, 
         FIG. 3A  is a schematic illustration of a wiper lip according to embodiments of the disclosure, 
         FIG. 3B  is a schematic illustration of a wiper lip according to embodiments of the disclosure, 
         FIG. 4  is a perspective illustration of an end of a windshield wiper device according to embodiments of the disclosure with a wiper lip according to embodiments of the disclosure, 
         FIG. 5  is a schematic pressure line of a wiper lip according to embodiments of the disclosure with a load which is perpendicular relative to the wiping direction, 
         FIG. 6A  is a schematic illustration of a wiper blade of a windshield wiper device according to embodiments of the disclosure in a basic position, 
         FIG. 6B  is a schematic illustration of the wiper blade of a windshield wiper device according to embodiments of the disclosure according to  FIG. 4A  in a position placed on a windshield, 
         FIG. 7A  is a schematic illustration of another embodiment of a windshield wiper device according to the invention in the form of a wiper arm with integrated wiper blade in a basic position, 
         FIG. 7B  is a schematic illustration of the wiper arm with integrated wiper blade according to  FIG. 7A  in a position placed on a windshield, 
         FIG. 8  is a schematic, perspective view of a wiper arm of a windshield wiper device according to embodiments of the disclosure, 
         FIG. 9A  is a schematic illustration of a cut-out of the wiper blade according to  FIG. 7A , 
         FIG. 9B  is a schematic illustration of a cut-out of the wiper blade according to  FIG. 7B . 
     
    
    
     DETAILED DESCRIPTION 
     Unless otherwise indicated, the same reference numerals are used below for elements which are the same and which have the same effect. 
       FIG. 1  is a schematic illustration of a wiper lip  50  according to embodiments of the disclosure. The wiper lip  50  is adapted to a windshield wiper device  100  which is described herein. According to embodiments of the disclosure, the wiper lip  50  is configured so that the rigidity of the wiper lip  50  in the wiping direction  1  is higher than the rigidity of the wiper lip  50  perpendicularly relative to the wiping direction  1 . There is thereby produced a wiper lip which has a high level of wiping quality and by means of which a noise is reduced, in particular when the movement direction of the wiper arm or the wiper blade is reversed in a turning position. 
     According to typical embodiments of the wiper lip  50 , as illustrated by way of example in  FIG. 1 , the wiper lip  50  comprises a base region  21  and a wiping region  22 . Typically, the base region  21  is configured to provide a constant pressing force which acts perpendicularly relative to the wiping direction  1  in the event of contact of the wiper lip  50  with a windshield. There is thereby produced a wiper lip which has a high level of wiping quality and by means of which a noise is reduced, in particular when the movement direction of the wiper arm or the wiper blade is reversed in a turning position. 
     As illustrated by way of example in  FIG. 1 , the wiping region  22  of the wiper lip  50  according to embodiments of the disclosure has a pointed end  25  and a wide end  26 . At the pointed end  25  of the wiper region  22 , there is typically arranged a wiping edge  23  which is typically in contact with the windshield to be wiped. According to embodiments of the disclosure, the wiper edge  23  is configured to provide a friction coefficient between the wiper lip and the windshield of a motor vehicle, in particular in a wet state of the windshield, of a maximum of 0.2, in particular a maximum of 0.1, in particular a maximum of 0.05. 
     According to embodiments described herein, the base region  21  of the wiper lip  50  is typically arranged at the wide end  26  of the wiping region  22 . As illustrated by way of example in  FIG. 1 , the base region  21  of the wiper lip  50  is wider than the wide end  26  of the wiper region  22 . A wiper lip is thereby provided in which the rigidity of the wiper lip is higher in the wiping direction than the rigidity of the wiper lip perpendicularly relative to the wiping direction. Consequently, a folding-over of the wiper lip, as known from the prior art, can be reduced or substantially prevented and a noise, in particular when the movement direction of the wiper arm or the wiper blade is reversed in a turning position can be reduced. 
     According to typical embodiments of the wiper lip, which can be combined with other embodiments, the wiper edge  23  comprises an angle α of from 60° to 120°, in particular 90°. A wiper lip with a good sealing action between the wiper lip and the windshield and a high wiping quality is thereby provided. 
     As shown by way of example in  FIG. 1 , the base region  21  of the wiper lip  20  according to embodiments described herein has a recess  24 . Typically, the recess  24  is arranged above the wide end  26  of the wiping region  22 . Typically, the wiping region  22  is arranged centrally relative to the recess  24  of the base region  21 . 
     According to embodiments of the wiper lip which can be combined with other embodiments, the recess  24  has a width B A  of at least 6 mm, in particular of at least 7 mm, in particular of at least 8 mm. Typically, the width B W  of the wide end  26  of the wiping region  22  is smaller than the width B A  of the recess  24 . According to typical embodiments of the wiper lip, the width B A  of the recess  24  and the width B W  of the wide end  26  of the wiping region  22  is selected in such a manner that a ratio of B W /B A  is a maximum of 0.8, in particular a maximum of 0.7, in particular a maximum of 0.6. 
     According to embodiments of the wiper lip which can be combined with other embodiments, the base region  21  has a width B B  of at least 10 mm, in particular at least 12 mm, in particular at least 15 mm. 
     According to embodiments of the wiper lip which can be combined with other embodiments, the recess  24  has a depth T A  of at least 1 mm, in particular at least 2 mm, in particular at least 3 mm. As explained in greater detail with reference to  FIG. 5 , as a result of the sizing of the depth T A  of the recess  24  in the base region  21  of the wiper lip, the spacing region between the wiper blade and windshield, in which a substantially constant pressing pressure is present between the wiper lip and windshield can be adjusted. In this instance, with an increase of the depth T A  of the recess  24 , the spacing region between the wiper blade and the windshield at which a substantially constant pressing pressure acts between the wiper blade and the windshield can be increased. 
     According to typical embodiments of the wiper lip, the height H B  of the base region  21  and the depth T A  of the recess  24  is selected in such a manner that a ratio of T A /H B  is a maximum of 0.8, in particular a maximum of 0.7, in particular a maximum of 0.6. 
     According to typical embodiments of the wiper lip which can be combined with other embodiments, the wiper lip may be produced from one or more materials from the group comprising: TPE (thermoplastic elastomer), for example, TPE-S, TPE-O, TPE-U, TPE-A, TPE-V, TPE-E; ethylene-propylene-diene rubber (EPDM); polychloroprene and natural rubber. 
     According to typical embodiments of the wiper lip which can be combined with other embodiments, the same material can be selected for the base region  21  of the wiper lip as for the wiping region  22  of the wiper lip. According to embodiments which are described herein, different materials can be selected for the base region  21  of the wiper lip and the wiper region  22  of the wiper lip. The base region  21  of the wiper lip may be produced from a first material from a group comprising: thermoplastic elastomer, for example, TPE-S, TPE-O, TPE-U, TPE-A, TPE-V, TPE-E; ethylene-propylene-diene rubber (EPDM); polychloroprene and natural rubber. The wiping region  22  of the wiper lip may be produced from a second material from a group comprising: thermoplastic elastomer, for example, TPE-S, TPE-O, TPE-U, TPE-A, TPE-V, TPE-E; ethylene-propylene-diene rubber (EPDM); polychloroprene and natural rubber. As a result of a material selection for the base region and for the wiping region, as a result of the respective material properties, the mechanical properties of the base region and the wiper region of the wiper lip can be adjusted. 
     Typically, the wiper lip according to embodiments of the present disclosure is produced by means of an extrusion method or an injection-molding method, in particular a dual component injection-molding method. The wiper lip can thereby be produced in a simple and cost-effective manner. The production of the wiper lip which is described herein by means of an extrusion method is particularly advantageous when ethylene-propylene-diene rubber (EPDM), polychloroprene or natural rubber is used. 
     According to embodiments of the wiper lip which can be combined with other embodiments, the wiper lip  50  has a hollow space  51 , as illustrated by way of example in  FIG. 2A . Typically, the hollow space  51  is configured in a tubular manner and extends in the longitudinal direction of the wiper lip. The ends of the tubular hollow space may be open, in particular air-permeable, or closed, in particular air-tight. The tubular hollow space may have a circular, an oval, a triangular, a rectangular or other suitable cross-sections. According to embodiments, the tubular hollow space is arranged in the base region  21  of the wiper lip. Via the sizing of the hollow space and the selection of the cross-section of the hollow space, the rigidity of the wiper lip can be adjusted. In particular the rigidity of the wiper lip can be adjusted in such a manner that a folding-over of the wiper lip, as known from the prior art, can be reduced or substantially avoided. Consequently, a wiper lip is provided by means of which a noise, in particular when the movement direction of the wiper arm or the wiper blade is reversed in a turning position, can be reduced. 
     According to embodiments of the wiper lip which can be combined with other embodiments, the hollow space  51  has an inner coating  52 , as illustrated by way of example in  FIG. 2B . According to embodiments of the wiper lip, the hollow space  51  is completely filled with the coating  52 . The coating  52  may be of a different material from that of the wiper lip. In particular it is possible to select for the coating  52  of the hollow space  51  a material which has a different rigidity from the material of the wiper lip. For example, in comparison with the material of the wiper lip for the coating, a material with a higher or lower rigidity can be selected. Consequently, a wiper lip is provided in which, on the one hand, via the material selection of the coating and via the thickness of the coating, the rigidity of the wiper lip can be adjusted. 
     According to embodiments of the wiper lip which can be combined with other embodiments, the base region  21  of the wiper lip  50  is configured in such a manner that the base region  21  can be lowered into a recess of a lower portion  12  of a windshield wiper device. According to embodiments, the base region  21  may have at least one indentation which is arranged in such a manner that, via the sizing of the at least one indentation, the rigidity of the wiper lip, in particular the rigidity of the wiper lip perpendicularly relative to the wiping direction, can be adjusted. 
     According to embodiments, the at least one indentation is arranged at an end of the base region  21  which is opposite the wiping region  22 , in particular the wiper edge  23 , as illustrated by way of example in  FIG. 3B . Furthermore, the wiper lip according to embodiments may be configured in such a manner that, after assembly of the wiper lip on a lower portion of a wiper blade by means of introduction of the base region  21  of the wiper lip  50  in a recess of the lower portion  12 , the wiper lip is only partially in contact with the wall of the recess of the lower portion. In particular, the wiper lip  50  may be configured in such a manner that a play is present after assembly of the wiper lip on a lower portion of a wiper blade, between the lateral regions of the base region  21  of the wiper lip at the end of the wiping region and the recess of the lower portion. Consequently, a wiper lip is provided which has a higher rigidity in the wiping direction than perpendicularly to the wiping direction. Consequently, there can be provided a wiper lip by means of which a noise, in particular when the movement direction of the wiper arm or the wiper blade is reversed in a turning position, can be reduced. 
     According to embodiments which can be combined with other embodiments, the at least one indentation is arranged laterally on the base region  21  of the wiper lip. As illustrated by way of example in  FIG. 3A , according to embodiments at least two lateral recesses are arranged on the base region in such a manner that they face each other, in particular face each other in an offset manner. Via the sizing, the number and arrangement of the lateral indentations in the base region of the wiper lip, the rigidity of the wiper lip, in particular the rigidity of the wiper lip perpendicularly relative to the wiping direction, can be adjusted. It is thereby possible to provide a wiper lip by means of which a noise, in particular when the movement direction of the wiper arm or the wiper blade is reversed in a turning position, can be reduced. Also in  FIG. 3A , the wiper lip is introduced into a recess of the lower portion. For these embodiments, as shown by way of example in  FIGS. 3A and 3B , the wiper lip can be adhesively bonded or axially fixed in another manner. This may be provided, for example, by an undercut portion or another shaping of the recess and a corresponding shaping of the wiper lip. 
       FIG. 4  is a perspective illustration of an exemplary wiper blade end of a windshield wiper device according to the embodiments described herein. As illustrated by way of example in  FIG. 4 , the wiper lip  50  is typically provided on the lower portion  12  of the wiper blade  2 . According to embodiments, the wiper lip may comprise the same material as the wiper blade. Alternatively, the lip may comprise a different material from the wiper blade. 
     According to embodiments of the disclosure, the wiper lip may be constructed integrally with the lower portion  12  of the wiper blade  2 . In this instance, the wiper lip and the lower portion of the wiper blade may at least partially comprise the same material. Alternatively, according to embodiments described herein, a receiving member may be provided on the lower portion  12  of the wiper blade so that the wiper lip  50  can be introduced. This affords the advantage that the wiper lip can be replaced separately and consequently, in contrast to replacing the entire wiper blade, a material saving is possible. According to another alternative, the wiper lip may be cold-welded to the lower portion of the wiper blade. 
       FIG. 5  illustrates by way of example a schematic pressure line for a wiper lip according to embodiments of the disclosure with a load which is perpendicular relative to the wiping direction. In this instance, the pressing pressure P between the wiper lip and windshield is applied when the spacing is reduced between the wiper blade and windshield. In  FIG. 5 , an increase of the x value means a reduction of the spacing between the wiper blade and windshield. As illustrated in  FIG. 5 , a pressing pressure line of the wiper lip according to the embodiments has a first region  31 , a second region  32  and a third region  33 . The first region  31  of the pressing pressure line describes the initial pressure increase, which occurs when the wiper lip comes into contact with the windshield. The second region  32  of the pressing pressure line describes the pressure path of the wiper lip during another reduction of the spacing between the wiper blade and windshield. As illustrated by way of example in  FIG. 5 , the pressing pressure in the second region  32  of the pressure line of the wiper lip is substantially constant or increases only slightly so that, for a specific spacing region between the wiper blade and windshield, that is to say, the length of the second region  32  of the pressure line, a substantially constant pressing pressure is present between the wiper lip and windshield. The third region  33  of the pressure line describes the pressing pressure of the wiper lip when the base of the recess  24  of the base region  21  comes into contact with the lower portion  12  of the wiper blade  2 . 
     As already explained, via the sizing of the depth of the recess  24  in the base region  21  of the wiper lip, the spacing region between the lower portion  12  of the wiper blade  2  and the windshield, in which a substantially constant pressing force is present between the wiper lip and the windshield, can be adjusted. This means that the second region  32  of the pressing pressure line which is illustrated in  FIG. 5  is extended as the depth of the recess  24 , in which a substantially constant pressing pressure is present, increases. 
     There is described below an exemplary windshield wiper device, for which the wiper lip described herein can be used. In principle, however, the wiper lip described herein can also be used for other windshield wiper devices. 
       FIGS. 6A and 6B  are schematic illustrations of a wiper blade  2  in a basic position ( FIG. 6A ) and in a position placed on a windshield ( FIG. 6B ) according to embodiments of the windshield wiper device of the disclosure. The wiper blade  2  serves to wipe a windshield  4  of a vehicle, which is, for example, a motor vehicle, in particular a car. Generally, the wiper blade  2  is fitted to a windshield wiper arm which is driven for wiping by means of a motor. To this end, the wiper blade  2  has a retention member  6 , with which it can be secured to the windshield wiper arm. The wiper blade  2  is located in  FIG. 6A  in a basic position in which it is at least partially raised from the windshield  4 . The wiper blade  2  has a longitudinal extent  8  and has an elongate upper portion  10  and a similarly elongate lower portion  12 . The longitudinal extent of the upper portion  10  and the lower portion  12  substantially correspond to the longitudinal extent  8  of the wiper blade  2 . 
     Both the upper portion  10  and the lower portion  12  are bendable bars or may be constructed as bendable bars which are constructed in  FIGS. 6A and 6B  by way of example in one piece in each case. This enables a particularly stable construction. It is also possible for only a portion of the upper portion  10  and/or the lower portion  12  to be constructed so as to be bendable. Furthermore, it is alternatively possible for the upper portion  10  to be constructed in two parts, wherein a respective end of the two portions of the two-part upper portion  10  are then secured to the retention member  6 . 
     According to some embodiments, which can be combined with the other embodiments described herein, for the upper portion  10  and/or the lower portion  12  there is used a material which has an elasticity modulus which is in a range between 0.005 kN/mm 2  and 0.5 kN/mm 2 , in particular 0.01 kN/mm 2  and 0.1 kN/mm 2 . This enables a suitable flexibility of the upper portion  10  and the lower portion  12 . Together with a suitably constructed cross-section face of the upper portion  10  and the lower portion  12 , an optimum flexural strength is thus produced. The upper portion  10  and the lower portion  12  are thus arranged in such a manner that they face each other. Both ends of the upper portion  10  are securely connected at outer connection positions  14  and  16  to an end of the lower portion  12 , respectively. Otherwise, the upper portion  10  and the lower portion  12  are spaced apart from each other. 
     The upper portion  10  and the lower portion  12  are connected to each other by means of connection elements  18 . In particular in the basic position of the wiper blade  2 , they extend substantially transversely relative to the longitudinal extent  8  of the wiper blade  2 . The connection elements  18  are secured at mutually facing inner longitudinal sides of the upper portion  10  and the lower portion  12  by means of pivot joints  20 . The pivot joints  20  are in this instance hinges. In particular, the pivot joints  20  may be constructed as film hinges. This is particularly advantageous when the upper portion  10 , lower portion  12  and/or connection elements  18  are produced from a plastics material or are covered with a suitable plastics material. 
     According to typical embodiments which are described herein and which can be combined with other embodiments described herein, a pivot joint is selected from the following group which comprises: a hinge, a film hinge, a tapering of the material for producing lower rigidity in accordance with a torsion axis, a joint with a rotation axis, a means for connecting the upper portion to the connection element or for connecting the lower portion to the connection element which permits the displacement of the lower portion with respect to the upper portion over the longitudinal extent, etcetera. 
     Embodiments in which the joint is provided by means of a film hinge consequently provide a very simple manner of providing the joints for a Fin-Ray wiper. The wiper blade  2  can be provided in one piece, in particular in an off-tool manner. According to typical embodiments, the film hinges have a high expandability. This may, for example, be provided by a material selected from the group PP, PE, POM and PA. Alternatively, the film hinges may be produced from one or more materials from a group comprising: TPE (thermoplastic elastomer), for example, TPE-S, TPE-O, TPE-U, TPE-A, TPE-V and TPE-E. 
     The connection elements  18  are spaced apart from each other over the longitudinal extent of the wiper blade  2 . The spacings between two adjacent connection elements  18  are the same. However, they may also be selected to be different. The spacings are advantageously smaller than 50 mm, in particular smaller than 30 mm. It is thereby possible to ensure particularly high flexibility of the windshield wiper device, in particular the lower portion thereof, and good adaptation to the curvature and curvature changes of the windshield to be wiped. In  FIG. 6A  in place of the spacings between two connection elements  18  in each case, a spacing  22  is illustrated. The connection elements  18  are, in particular in the basic position of the wiper blade  2 , secured to the lower portion  12  in such a manner that the longitudinal axes thereof extend at angles  26  with respect to the lower portion  12  which are between 65° and 115°, in particular between 75° and 105°. In a particularly advantageous manner, the angles are between 80° and 100°. This advantageously ensures a particularly good transmission of a force acting on the lower portion to the upper portion. It is further possible in this manner to achieve a particularly stable windshield wiper device. The same applies to the fixing means of the connection elements  18  to the upper portion  10 . 
     The same applies in the present embodiment to the fixing means of the connection elements  18  to the upper portion  10 . 
       FIG. 6A  illustrates by way of example of the longitudinal axes of the connection elements  18  a longitudinal axis  24  and by way of example of the angles between the connection elements  18  and the lower portion  12  an angle  26 . The spacings between the upper portion  10  and the lower portion  12  are determined above all by the lengths of the connection elements  18 . The lengths of the connection elements  18  increase starting from the two outer connection positions  14 ,  16  as far as approximately those locations at which the retention member  6  which is fitted to the upper portion  10  begins. The upper portion  10  and lower portion  12  thereby form in the side view of the wiper blade  2  according to  FIG. 6A  a double-wedge, wherein the tips of the two wedges face in opposing directions. The connection elements  18  are constructed in a buckle-resistant manner. 
       FIG. 6B  is a schematic illustration of the wiper blade  2  according to  FIG. 6A  in a position placed on the windshield  4 . Since the windshield  4  has a curvature, when the wiper blade  2  is placed on the windshield  4 , contact pressure forces act on the lower portion  12 . Since the upper portion  10  and the lower portion  12  are bendable bars and the connection elements  12  are rotatably supported on the upper portion  10  and lower portion  12 , the upper portion  10  and the lower portion  12  can be displaced relative to each other. As a result of the pressure forces acting from below on the lower portion  12 , the wiper blade  2  bends in the direction from which the pressure forces originate and is applied precisely with respect to the curvature of the windshield  4 . 
     As a result of the structure of the embodiments described herein, when a force acts on the lower portion (as a result of the windshield  4 ), there is a bending of the lower portion in the direction from which the force acts. This is produced by means of the connection of the upper portion  10  and the lower portion at a connection position  14  and/or  16 , the shape and pivot joints at the connection between the connection elements and the upper or lower portion. 
     In the illustration according to  FIG. 6B , there is provided between the wiper blade  2  and the windshield  4  a small spacing which serves in this instance only to explain the windshield  4  and the wiper blade  2  and which in reality is substantially not present in this manner when the wiper blade  2  is placed on the windshield  4 . Furthermore, there is typically at the lower side of the lower portion  12  facing away from the upper portion  10  a wiper lip  50  according to the embodiments described herein, as illustrated by way of example in  FIG. 1 , which is placed for wiping on the windshield  4 . For reasons of clarity, the wiper lip is not illustrated in  FIGS. 6A and 6B . 
     A windshield wiper device according to embodiments described herein uses the effect of tail fins of specific fish, which in the event of lateral pressure do not deviate in the pressure direction, but instead curve in the opposite direction, that is to say, in the direction from which the pressure originates. This principle is also referred to as the “fin ray” principle. A windshield wiper device according to the embodiments described herein thereby has the advantage of improved adaptation to a windshield of a motor vehicle. With a conventional windshield wiper blade, the upper portion thereof is generally rigid, that is to say, it is constructed so as not to be bendable. 
       FIGS. 6A and 6B  show a wiper blade  2  with a longitudinal extent  8  which extends substantially between the connection positions  14  and  16 . Such an arrangement is often used for front windshield wipers. Alternatively, however, a windshield wiper device may also have only one connection position which, by analogy with  FIGS. 6A and 6B  corresponds to a halving of the windshield wiper device, and wherein, for example, at a position of the retention member  6  a rotation axis is provided. Such an arrangement is often used for rear windshield wipers. This is illustrated by way of example inter alia in 
       FIGS. 7A and 7B . Optional embodiments and details, as described in the individual embodiments, can generally be used for both variants of an arrangement of a windshield wiper device. 
       FIG. 7A  is a schematic illustration of another embodiment of the windshield wiper device according to the invention in the basic position. The windshield wiper device is in this instance a wiper arm with an integrated wiper blade  2 , which is fitted to a securing portion  30 . The securing portion  30  is connected to a wiper motor  32  which drives the securing portion  30  for wiping the windshield  4 . The wiper blade  2  is constructed in a wedge-shaped manner, wherein an end of the upper portion  10  at an outer connection position  34  is securely connected to an end of the lower portion  12 . The other end of the upper portion  10  and the lower portion  12  is secured to the securing portion  30 , respectively. With regard to the basic structure and in particular the securing means of the connection elements  18 , the windshield wiper device according to  FIG. 7A  in principle corresponds to the one according to  FIG. 6A . 
       FIG. 7B  is a schematic illustration of the wiper blade  2  with integrated wiper arm  30  according to  FIG. 7B  in a position placed on the windshield  4 . Also in this instance, pressure forces act from below from the direction of the windshield  4  on the lower portion  12  of the wiper blade  2  so that the lower portion  12  and the upper portion  10  bend in the direction of the windshield  4 . 
     Both in  FIG. 6A  and in  FIG. 7A , the wiper blade is illustrated in the position thereof not placed on the windshield in such a manner that the lower portion  12  is constructed in a substantially straight manner. According to other embodiments which can be combined with other embodiments, the lower portion is constructed in a convex manner in the unloaded state, that is to say, with a curvature which protrudes away from the upper portion in a central region. The windshield wiper device according to the embodiments described herein can typically, in the event of contact with a windshield, starting from the convex shape of the lower portion, then assume the corresponding concave shape of the lower portion, which is adapted to the windshield. 
       FIG. 8  is a schematic, perspective illustration of a wiper blade  2  of a windshield wiper device according to embodiments of the disclosure. As illustrated in  FIG. 8 , the wiper blade  2  has at the outer connection positions, at which the ends of the elongate upper portion  10  and the lower portion  12  are connected to each other, an outer width W E . According to typical embodiments, the outer width W E  is at least 15 mm, in particular at least 20 mm, in particular at least 25 mm. 
     According to embodiments of the disclosure which can be combined with other embodiments, the width of the wiper blade  2  increases from the outer connection positions in the direction of the securing portion  30  or the retention member  6  to which the wiper blade on the windshield wiper arm can be secured. In  FIG. 8 , an inner width is designated W M  by way of example. According to typical embodiments, the inner width W M  is at least 20 mm, in particular at least 25 mm, in particular at least 30 mm. 
       FIG. 9A  is a schematic illustration of a cut-out of the wiper blade  2  according to the embodiment according to  FIG. 7A  in which the wiper blade  2  is located in the basic position. The left end region of the wiper blade  2  in which an end of the upper portion  10  and an end of the lower portion  12  are secured to the securing portion  30  is illustrated.  FIG. 9A  shows starting from the transition from the securing portion  30  to the wiper blade  2  the first two connection elements  18  which delimit two wiper blade elements  36  and  38 . The connection elements  18  are secured to the upper portion  10  and the lower portion  12  by means of pivot joints  20 . 
       FIG. 9B  is a schematic illustration of a cut-out of the wiper blade  2  according to the embodiment according to  FIG. 7B , in which the wiper blade  2  is placed on the windshield  4 . Pressure forces act on the lower portion  12  from below from the direction of the windshield. In place of the pressure forces, a pressure force  40  is illustrated in  FIG. 9B . The pressure force  40  brings about a curvature and bending of the lower portion  12  of the wiper blade element  36 . The pivot joint  20  of the first connection element  18  is thereby displaced by a distance s to the left. The second wiper blade element  38  bends downward in the direction from which the pressure force  40  originates and fits closely against the windshield. An angle  42  is produced in this case between the first wiper blade element  36  and the second wiper blade element  38 . There is further formed an additional pressure force which then acts on the lower portion  12  of the second wiper blade element  38  and prevents further bending of the second wiper blade element  38  in a downward direction. A chain reaction is produced with respect to the right-hand adjacent wiper blade element as far as the end of the wiper blade  2 . 
     According to embodiments of the disclosure, on the lower portion  12  of the wiper blade  2 , for example, on wiper blades as illustrated by way of example in  FIGS. 6A, 6B, 7A and 7B , a wiper lip  50  according to the embodiments described herein is provided. The wiper lip  50  wipes over the windshield of the vehicle in order to clean it. With off-tool wiper blades, this may be provided integrally in a preferred embodiment. 
     According to another embodiment, in order to produce a wiper lip and a wiper blade in a cost-effective and economical manner, the lower portion  12 , or, for the entire wiper blade  2 , also the upper portion  10 , and the connection elements  18 , is produced from a first material. Typically, this may be the same material or different materials can also be selected for the individual components. These materials may be selected from a group comprising: TPE (thermoplastic elastomer), TPE-S, TPE-O, TPE-U, TPE-A, TPE-V and TPE-E, wherein materials which are cost-effective to obtain or which can be produced in a cost-effective manner can be used. 
     The wiper lip  50  and the joint  20  on the lower portion  12  may be produced from a different material which complies with the increased requirements with respect to flexural rigidity, creep resistance or other requirements. Since, with such an embodiment of a joint for a wiper blade or a wiper lip for a wiper blade, only a limited material requirement for the joint and the wiper lip exists, higher quality (and more costly) materials can be used, without excessively increasing the overall costs of the wiper blade. 
     It is possible to construct a rigid or relatively rigid rib or a rigid connection element, the lower portion and the upper portion from a plastics material. This may, for example, be a fiber-reinforced plastics material. The joint  20  and the rubber profile of the wiper lip  50  are produced from a rubber-like material. The two different materials may, for example, be provided in a 2-component injection-molding method. According to typical embodiments, it is possible to use as a rubber-like material a thermoplastic elastomer (TPE), for example, TPE-S, TPE-O, TPE-U, TPE-A, TPE-V and TPE-E; ethylene-propylene-diene rubber (EPDM); polychloroprene or natural rubber. 
     Optionally, the TPE joint can be provided independently of the wiper rubber profile, that is to say, the wiper lip. However, in the same injection-molding tool, the rubber profile of the wiper lip and/or, for example, also a styling of the surface can also be produced. By means of such a reduction of the injection-molding tools, the production costs can be reduced. 
     According to the embodiments described herein, materials can be selected so as to enable, even with high temperature fluctuations and/or with consistently high ambient temperatures, a reliable or durable windshield wiper device. The material selection of the film hinges, in particular together with the thickness of the hinges, enables flexural rigidity at a predetermined value or below and further enables production using the injection-molding method, with corresponding properties of the wiper blade, for example, an adequate creep resistance of the pivot joints. 
     According to the embodiments described herein, Fin-Ray windshield wiper devices for vehicle windshields can be produced in a particularly cost-effective manner and/or for a plurality of different fields of application. The present embodiments of the windshield wiper device with the wiper lip according to the embodiments described herein enable a particularly good adaptation to the curvature of a windshield. This ensures particularly good and precise wiping of the windshield. Regions of the windshield which are not wiped and a formation of haze on the windshield can be substantially prevented. The structural configuration of the wiper lip described herein enables a substantially uniform pressing pressure of the wiper lip on the windshield so that a high wiping quality is provided and a noise, in particular when the movement direction of the wiper arm or the wiper blade is reversed in a turning position, is prevented or at least reduced.