Patent Publication Number: US-9849861-B2

Title: Wiper blade

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This is continuation application of U.S. patent application Ser. No. 13/689,140 (allowed), filed Nov. 29, 2012, which claims priority from Korean Patent Application No. 10-2011-0127918 filed on Dec. 1, 2011 and Korean Patent Application No. 10-2012-0073347 filed on Jul. 5, 2012, the entire subject matters of which are incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present invention relates to a wiper blade for wiping a windshield of a motor vehicle. More particularly, the present invention relates to a wiper blade with a spoiler. 
     BACKGROUND 
     Motor vehicles are equipped with a windshield wiper device for cleaning or wiping a surface of a windshield. The windshield wiper device includes a wiper blade, a wiper arm and a wiper motor oscillating the wiper arm. The wiper blade is releasably coupled to the wiper arm. The wiper blade is placed on the surface of the windshield by the wiper arm. The wiper blade wipes the surface of the windshield while sliding thereon through oscillation motions of the wiper arm. 
     The wiper blade has an elongated wiper rubber and a frame structure. The wiper rubber is placed in contact with the windshield surface. The frame structure holds and supports the wiper rubber along its length. The frame structure may include an assembly having a main lever and a plurality of yoke levers linked to the main lever. The main lever is connected to the wiper arm. The yoke lever is linked to the main lever or another yoke lever at its middle. The yoke levers hold the wiper rubber. 
     When a motor vehicle runs, wind or air stream impinging against the windshield applies a force to the wiper blade along the entire length of the wiper blade placed on the windshield. The wiper blade generally stands upright on the surface of the inclined windshield. Thus, the force applied by the wind or air stream acts in a direction of lifting the wiper blade from the surface of the windshield. The faster the motor vehicle runs, the stronger such a lift force would be. This weakens the contact between the wiper rubber and the windshield surface, thus deteriorating wiping performance. 
     To address the deterioration in wiping performance caused by the lift of a wiper blade, it is known in the art to attach a spoiler to the wiper blade. The spoiler interacts with wind or air stream and thereby applies a force in a direction opposite to the lift of the wiper blade. By way of example, Korean Patent Application Publication No. 10-2003-0031158 discloses a wiper blade with a spoiler attached to a main lever. It is also disclosed in the art to attach a cover to a wiper blade so as to cover a main lever and a yoke lever. By way of another example, Korean Patent Application Publication No. 10-2006-0051763 discloses a wiper blade with such a cover. 
     SUMMARY 
     The lower an entire height of the lever assembly holding the wiper blade, the less air resistance the lever assembly could be subjected to. However, the prior art lever assembly of the wiper blade has difficulties in reducing its entire height due to a furcate configuration of its levers. The wiper blade with the spoiler attached to the lever assembly requires that the spoiler be prepared separately from and attached to the lever assembly. This may increase manufacturing cost of the wiper blade and further lead to detachment of the spoiler from the wiper blade. Further, the wiper blade with the cover covering the lever assembly needs parts for joining the cover to the lever assembly. This may increase the number of the parts of the wiper blade and cause increase in manufacturing cost. 
     The present invention is directed to solving the aforementioned problems of the prior art. The present invention provides a wiper blade wherein a lever assembly holding a wiper rubber has a low entire height. Further, the present invention provides a wiper blade wherein a spoiler is integrated in a lever assembly. 
     In one exemplary embodiment of the present invention, the wiper blade includes a wiper rubber and a lever assembly holding the wiper rubber and coupled to a wiper arm. The lever assembly includes a plurality of levers, adjacent levers of which are hinge-jointed to each other. The lever includes a spoiler portion forming a section of a spoiler, which is integrated in the lever. 
     In an embodiment of the present invention, the spoiler portion includes an inclined surface extending in a longitudinal direction of the wiper rubber and defining the section of a spoiler. At least a portion of a lateral surface of the spoiler portion forms the inclined surface. 
     In an embodiment of the present invention, the inclined surface comprises a forward inclined surface facing forward in a running direction of a motor vehicle and a backward inclined surface opposed to the forward inclined surface. The lever has at least one air hole in the backward inclined surface. 
     In an embodiment of the present invention, one of the adjacent levers includes an arm extending from the spoiler portion thereof toward the other of the adjacent levers and holding the wiper rubber at a distal end. The arm is situated in and hinge-jointed to the spoiler portion of the other of the adjacent levers. The arm is hidden in the spoiler portion of the other of the adjacent levers. The arm and the spoiler portion of the one of the adjacent levers extend straight. 
     In an embodiment of the present invention, the other of the adjacent levers includes a joint portion extending from the spoiler portion thereof toward the one of the adjacent levers and hinge-jointed to the arm. The lever assembly further includes a joint cover that is coupled to the joint portion between the one of the adjacent levers and the other of the adjacent levers. The joint cover has a cross-sectional profile corresponding to a cross-sectional profile of the spoiler portion of the one of the adjacent levers and a cross-sectional profile of the spoiler portion of the other of the adjacent levers. 
     In an embodiment of the present invention, the lever assembly further includes a joint nested on and hinge-jointed to the arm. The joint is coupled to the spoiler portion of the other of the adjacent levers. 
     In an embodiment of the present invention, one of the arm and the spoiler portion of the other of the adjacent levers includes a pair of hinge pins, while the other of the arm and the spoiler portion of the other of the adjacent levers includes a pair of fitting holes to which the pair of the hinge pins are fitted respectively. The spoiler portion of the other of the adjacent levers includes a pair of raised portions therein. The raised portions are spaced apart to receive the arm. Opposing end surfaces of the adjacent levers are inclined at an acute angle toward an end of the wiper rubber. An outermost lever of the levers includes: a clamp formed at an end portion of the spoiler portion thereof and holding the wiper rubber; and a pressing portion located opposite to the clamp and bringing the wiper rubber into contact with the clamp. The lever has a plurality of transverse ribs and a longitudinal rib intersecting the transverse ribs. 
     In an embodiment of the present invention, an outermost lever of the levers includes a clamp formed at an end portion of the spoiler portion thereof and holding the wiper rubber; and a clamp insert fitted to the clamp and bringing the wiper rubber into contact with the clamp. 
     In an embodiment of the present invention, the lever assembly includes a covering sheet covering an interior of the lever assembly. 
     In an embodiment of the present invention, the section of a spoiler comprises a central spoiler and an end spoiler adjoining the central spoiler and the plurality of the levers comprises a central lever and a pair of end levers. The central lever includes a pair of central spoiler portions each forming the central spoiler and is coupled to the wiper arm between the central spoiler portions. Each of the end levers includes an end spoiler portion and an end arm. The end spoiler portion forms the end spoiler and adjoins the central spoiler portion. The end spoiler portion holds the wiper rubber. The end arm is hidden in and hinge-jointed to the central spoiler portion. The end arm extends from the end spoiler portion toward the central lever and holds the wiper rubber. 
     In an embodiment of the present invention, the section of a spoiler comprises a central spoiler, an intermediate spoiler adjoining the central spoiler and an end spoiler adjoining the intermediate spoiler. The plurality of the levers comprises a central lever, a pair of intermediate levers and a pair of end levers. The central lever includes a pair of central spoiler portions each forming the central spoiler and is coupled to the wiper arm between the central spoiler portions. Each of the intermediate levers includes an intermediate spoiler portion and intermediate arm. The intermediate spoiler portion forms the intermediate spoiler and adjoins the central spoiler portion. The intermediate arm is hidden in and hinge-jointed to the central spoiler portion. The intermediate arm extends from the intermediate spoiler portion toward the central lever and holds the wiper rubber. Each of the end levers includes an end spoiler portion and an end arm. The end spoiler portion forms the end spoiler and adjoins the intermediate spoiler portion. The end spoiler portion holds the wiper arm. The end arm is hidden in and hinge-jointed to the intermediate spoiler portion. The end arm extends from the end spoiler portion toward the intermediate lever and holds the wiper rubber. The intermediate lever includes a yoke lever that is hinge-jointed to a distal end of the intermediate arm and holds the wiper rubber at both ends. 
     In an embodiment of the present invention, the spoiler has a cross-sectional profile that varies in a longitudinal direction of the wiper rubber or includes one of a triangle with both curved legs, a semicircle and a semiellipse. 
     In the wiper blades according to the embodiments, the lever assembly includes a plurality of levers and the spoiler portion of each lever forms the section of a spoiler of the wiper blade. The lever assembly is configured such that the spoiler portions of the respective levers are straight adjoined one after another and a portion of one lever except for its spoiler portion is hidden in the spoiler portion of another adjacent lever. Thus, the lever assembly has a low entire height and the spoiler portions adjoined one after another in the lever assembly form a spoiler of the wiper blade. Accordingly, due to the lever assembly with the spoiler integrated therein and having straight-adjoined levers, the wiper blade can have a smaller number of parts and effectively prevent its lift. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Arrangements and embodiments may be described in detail with reference to the following drawings in which like reference numerals refer to like elements or components, wherein: 
         FIG. 1  is a perspective view showing a wiper blade in accordance with a first embodiment; 
         FIG. 2  is a top view of the wiper blade shown in  FIG. 1 ; 
         FIG. 3  is a front elevational view of the wiper blade shown in  FIG. 1 ; 
         FIG. 4  is a left side view of the wiper blade shown in  FIG. 1 ; 
         FIG. 5  is a right side view of the wiper blade shown in  FIG. 1 ; 
         FIG. 6  is a sectional view taken along the line  6 - 6  in  FIG. 1 ; 
         FIG. 7  is a sectional view taken along the line  7 - 7  in  FIG. 1 ; 
         FIG. 8  is a perspective view showing a wipe rubber and spring rails of the wiper blade according to the first embodiment; 
         FIG. 9  is a fragmental front view of the wiper rubber shown in  FIG. 8 ; 
         FIG. 10  is a front view of a central lever of the wiper blade according to the first embodiment; 
         FIG. 11  is a top view of the central lever shown in  FIG. 10 ; 
         FIG. 12  is a bottom view of the central lever shown in  FIG. 10 ; 
         FIG. 13  is a left side view of the central lever shown in  FIG. 10 ; 
         FIG. 14  is a front view of an end lever of the wiper blade according to the first embodiment; 
         FIG. 15  is a top view of the end lever shown in  FIG. 14 ; 
         FIG. 16  is a bottom view of the end lever shown in  FIG. 14 ; 
         FIG. 17  is a right side view of the end lever shown in  FIG. 14 ; 
         FIG. 18  is a left side view of the end lever shown in  FIG. 14 ; 
         FIG. 19  is an upper perspective view of a clamp insert; 
         FIG. 20  is a lower perspective view of the clamp insert shown in  FIG. 19 ; 
         FIG. 21  is a right side view of the clamp insert shown in  FIG. 19 ; 
         FIG. 22  is a front view of the clamp insert shown in  FIG. 19 ; 
         FIG. 23  depicts the insertion of the clamp insert to a clamp; 
         FIG. 24  shows the end lever with the clamp insert fitted thereto; 
         FIG. 25  is a front view showing an assembly example of the wiper blade according to the first embodiment; 
         FIG. 26  is a front view of a hinge insert; 
         FIG. 27  is a left side view of the hinge insert shown in  FIG. 26 ; 
         FIG. 28  is a right side view of a joint cover; 
         FIG. 29  is a longitudinally sectional view of the joint cover shown in  FIG. 28 ; 
         FIG. 30  is a perspective view showing a wiper blade in accordance with a second embodiment; 
         FIG. 31  is a top view of the wiper blade shown in  FIG. 30 ; 
         FIG. 32  is a front view of the wiper blade shown in  FIG. 30 ; 
         FIG. 33  is a left side view of the wiper blade shown in  FIG. 30 ; 
         FIG. 34  is a right side view of the wiper blade shown in  FIG. 30 ; 
         FIG. 35  is a front view of an intermediate lever of the wiper blade according to the second embodiment; 
         FIG. 36  is a top view of the intermediate lever shown in  FIG. 35 ; 
         FIG. 37  is a bottom view of the intermediate lever shown in  FIG. 35 ; 
         FIG. 38  is a left side view of the intermediate lever shown in  FIG. 35 ; 
         FIG. 39  is a left side view of an end lever of the wiper blade according to the second embodiment; 
         FIG. 40  is a top view of the end lever shown in  FIG. 39 ; 
         FIG. 41  is a bottom view of the end lever shown in  FIG. 39 ; 
         FIG. 42  is a left side view of the end lever shown in  FIG. 39 ; 
         FIG. 43  is a front view showing an assembly example of the wiper blade according to the second embodiment; 
         FIG. 44  is a perspective view showing a wiper blade in accordance with a third embodiment; 
         FIG. 45  is a top view of the wiper blade shown in  FIG. 44 ; 
         FIG. 46  is a front view of the wiper blade shown in  FIG. 44 ; 
         FIG. 47  is a front view of a central lever of the wiper blade according to the third embodiment; 
         FIG. 48  is a bottom view of the central lever shown in  FIG. 47 ; 
         FIG. 49  is a front view of an intermediate lever of the wiper blade according to the third embodiment; 
         FIG. 50  is a top view of the intermediate lever shown in  FIG. 49 ; 
         FIG. 51  is a left side view of the intermediate lever shown in  FIG. 49 ; 
         FIG. 52  is a front view of a yoke lever of the wiper blade according to the third embodiment; 
         FIG. 53  is a right side view of the yoke lever shown in  FIG. 52 ; 
         FIG. 54  is a front view of a hinge insert of the yoke lever; 
         FIG. 55  is a top view of the hinge insert shown in  FIG. 54 ; 
         FIG. 56  is a front view showing an assembly example of the wiper blade according to the third embodiment; 
         FIG. 57  is a front view of a wiper blade in accordance with a fourth embodiment; 
         FIG. 58  is a top view of the wiper blade shown in  FIG. 57 ; 
         FIG. 59  depicts a coupling example between a joint and an intermediate lever in the wiper blade according to the fourth embodiment; 
         FIG. 60  depicts a coupling example between an intermediate lever and a central lever in the wiper blade according to the fourth embodiment; 
         FIG. 61  is a perspective view showing a wiper blade in accordance with a fifth embodiment; 
         FIG. 62  is a top view of the wiper blade shown in  FIG. 61 ; 
         FIG. 63  is a front view of the wiper blade shown in  FIG. 61 ; 
         FIG. 64  is an exploded perspective view of a lever assembly of the wiper blade according to the fifth embodiment; 
         FIG. 65  is a lower perspective view of the lever assembly shown in  FIG. 64 ; 
         FIG. 66  is a left side view of a central lever of the lever assembly shown in  FIG. 64 ; 
         FIG. 67  is a fragmentary longitudinal sectional view of the central lever of the lever assembly shown in  FIG. 64 ; 
         FIG. 68  is a left side view of an intermediate lever of the lever assembly shown in  FIG. 64 ; 
         FIG. 69  is a longitudinal sectional view of the intermediate lever of the lever assembly shown in  FIG. 64 ; 
         FIG. 70  is a left side view of an end lever of the lever assembly shown in  FIG. 64 ; 
         FIG. 71  is a longitudinal sectional view of the end lever of the lever assembly shown in  FIG. 64 ; 
         FIG. 72  depicts an assembly example of the wiper blade according to the fifth embodiment; 
         FIG. 73  is a rear perspective view of a wiper blade in accordance with a sixth embodiment; 
         FIG. 74  is a top view of the wiper blade shown in  FIG. 73 ; 
         FIG. 75  is a rear view of the wiper blade shown in  FIG. 73 ; 
         FIG. 76  is a schematic sectional view taken along the line  76 - 76  in  FIG. 73 ; 
         FIG. 77  is a rear view of the wiper blade according to the sixth embodiment showing another example of an air hole; 
         FIG. 78  is a schematic sectional view taken along the line  78 - 78  in  FIG. 77 ; 
         FIG. 79  is an exploded perspective view of a wiper blade in accordance with a seventh embodiment; 
         FIG. 80  is a bottom view of the wiper blade shown in  FIG. 79 ; 
         FIG. 81  shows an example of a cross-section of the wiper blade shown in  FIG. 79 ; 
         FIG. 82  is similar to  FIG. 3  and shows another example of a cross-sectional profile of a spoiler; and 
         FIG. 83  is similar to  FIG. 6  and shows yet another example of a cross-sectional profile of a spoiler. 
     
    
    
     DETAILED DESCRIPTION 
     Detailed descriptions are made as to embodiments of a wiper blade with reference to the accompanying drawings. The directional term “upper,” “upward” or the like as used herein is generally based on a position, in which a lever assembly is disposed relative to a wiper rubber in the drawings, while the directional term “lower,” “downward” or the like generally refers to a direction opposite to the upper or upward direction. A wiper blade shown in the accompanying drawings may be otherwise oriented (e.g., rotated 180 degrees or at other orientations) and the aforementioned directional terms may be interpreted accordingly. Further, as used herein, the term “longitudinal inner end” or “longitudinal inner end portion” generally refers to an end that is closer to a center of a wiper blade in a longitudinal direction of an element, while the term “longitudinal outer end” or “longitudinal outer end portion” refers to the other end opposite to the inner end or the inner end portion. 
     Wiper blades according to embodiments have a lever assembly that holds or retains a wiper rubber to be placed on a surface of a windshield. The lever assembly is coupled to a wiper arm and supports the wiper rubber. The lever assembly includes a plurality of levers, which are joined straight one after another in a longitudinal direction of the wiper rubber and are at substantially the same height on the wiper rubber. Two adjacent levers are hinge-jointed to each other. 
     Further, the wiper blades according to embodiments include a spoiler that produces a reaction force preventing the lift of the wiper blade, which wind or air stream may cause. The spoiler is integrated in the lever assembly in the longitudinal direction of the wiper blade. A spoiler section, which becomes a section of the spoiler, is integrated in each lever of the lever assembly. That is, each lever has a spoiler portion defining said spoiler section. Since the levers are arranged in a straight line, the spoiler portions of the respective levers are adjoined one after another, thus forming the portion or the entirety of the spoiler. 
     The spoiler portion has at least one or a pair of inclined surfaces that produce the reaction force preventing the lift caused by wind or air stream. The inclined surface extends in the spoiler portion in the longitudinal direction of the wiper rubber and defines the spoiler section that is located in each lever. Further, the inclined surface forms the portion or the entirety of a lateral surface of the spoiler portion. The inclined surface may include a flat surface, a concave or convex curved surface, etc. The pair of the inclined surfaces may be at least partially symmetrical in a width direction of each lever. Further, one of the pair of the inclined surfaces may have a width larger than that of the other. 
     One or more levers among the levers of the lever assembly have a holding portion configured to hold the wiper rubber. The holding portion comprises an arm that extends from the spoiler portion provided in one of two adjacent levers toward the other of the adjacent levers, which is further inward or outward than the one of the adjacent levers in the lever assembly. Lower edges of the arm and the spoiler portion are approximately straight. That is, the arm and the spoiler extend in a straight line. The adjacent levers are joined to each other in such a manner that the arm of one of the levers is situated in the spoiler portion of the other of the levers and the arm and the spoiler portion of the other lever are hinge-jointed to each other. When the adjacent levers are joined together, the respective spoiler portions are at an approximately equal height on the wiper rubber and the arm of one of the adjacent levers is hidden inside the spoiler portion of the other adjacent levers. 
     In the embodiments, the lever assembly has a central lever to be coupled to a wiper arm. The lever assembly is constructed in such a manner that levers configured to hold the wiper rubber are joined to the central lever. In one embodiment, the lever assembly includes a central lever and a pair of end levers, thus holding the wiper rubber at four pressure points. The central lever is located in the middle of the lever assembly and the end levers are located at an outermost position in the lever assembly. In another embodiment, the lever assembly includes a central lever, a pair of intermediate levers and a pair of end levers, thus holding the wiper rubber at six or eight pressure points. The intermediate lever is interposed between the central lever and the outermost end lever. 
       FIGS. 1 to 29  show a wiper blade according to a first embodiment, generally denoted by  100 , and elements or components constituting the wiper blade  100 . The wiper blade  100  has a wiper strip or wiper rubber  110 , which is placed on a surface of a windshield of a motor vehicle, and a lever assembly  1000  holding the wiper rubber  110 . Further, the wiper blade  100  includes a pair of spoilers  130 L,  130 R that produce a reaction force preventing the lift caused by wind or air stream. The left spoiler  130 L and the right spoiler  130 R are symmetrical relative to a longitudinal center of the wiper rubber  110 . The spoilers  130 L,  130 R are integrally formed in the lever assembly  1000  and extend in the longitudinal direction of the wiper rubber  110 . 
     The wiper rubber  110  may be made from a rubber or plastic material having elasticity. Referring to  FIGS. 8 and 9 , the wiper rubber  110  has an elongated body portion  111  and a wiper lip  112  longitudinally extending beneath the body portion  111  and contacting the windshield surface. Further, the wiper rubber  110 , at either side of the body portion  111 , has two rows of grooves  113 ,  114  that extend in the longitudinal direction of the wiper rubber. A first groove  113  extends along the body portion  111  right below a top side of the body portion  111 . A second groove  114  extends along the body portion  111  below the first groove  113 . Spring rails  120  are inserted to the first grooves  113  respectively. Both ends of a clamp provided in a lever of the lever assembly  1000  are fitted to the second grooves  114  respectively. Further, a portion, to which an outermost clamp of the clamps of the levers is fitted, is formed in the vicinity of one end of the wiper rubber  110 . That is, in the vicinity of the one end of the wiper rubber  110 , stoppers  115  protrude between the top side and the first grooves  113  and recesses  116  are defined in edges of the top side due to the stoppers  115 . Further, insertion holes  117 , to which the ends of the outermost clamp are inserted to, are formed below the recesses  116 . The insertion holes  117  are located in the vicinity of the one end of the second groove  114 . When the lever assembly  1000  and the wiper rubber  110  are assembled together, the ends of the outermost clamp are fitted to the insertion holes  117  and a part to be inserted to the outermost clamp (this will be described below) is placed in the recesses  116 , thus holding the wiper rubber  110  against the outermost clamp. 
     The spring rails  120  (referred to as a “vertebra” in the art) are inserted to the wiper rubber  110  in the longitudinal direction and impart rigidity to the wiper rubber  110 . Further, the spring rails  120  distribute pressure applied by a wiper arm, along the entire length of the wiper rubber  110 . The spring rails  120  are made from a metallic material and have a shape of a thin elongated bar. The spring rails  120  are inserted to the first grooves  113  of the wiper rubber  110  respectively. The spring rail  120  has a concave notch  121  at either end and the first groove  113  has a protrusion  118  engaging the notch. Some embodiments may include the spring rails  120  that are inlaid or embedded to the body portion  111  of the wiper rubber  110 . 
     The lever assembly  1000  connects the wiper rubber  110 , to which the spring rails  120  are fitted to (hereinafter, the wiper rubber with the spring rails fitted thereto is referred to as a “wiper rubber assembly  110 ,  120 ”), to a wiper arm (not shown) of a wiper device. Further, the lever assembly  1000  supports the wiper rubber assembly  110 ,  120  with respect to the wiper arm. The wiper arm is coupled to a rotating shaft of a wiper motor of the wiper device at its base end and is oscillated by the wiper motor. The wiper blade  100  is coupled to the wiper arm in such a manner that the lever assembly  1000  is releasably attached to a distal end of the wiper arm. The wiper blade  100  wipes the surface of the windshield while sliding thereon through oscillation motions of the wiper arm. In this embodiment, the lever assembly  1000  includes a central lever  1100  centrally located with respect to the wiper rubber assembly  110 ,  120  and a pair of end levers  1300 L,  1300 R joined to the central lever respectively. The levers have an elongated hollow shape and may be made by pressing a metallic sheet or injection-molding a plastic material. 
     Referring to  FIGS. 1 to 3 , the pair of the spoilers  130 L,  130 R are formed in an upper surface of the lever assembly  1000  along its longitudinal direction (or along the longitudinal direction of the wiper rubber  110 ). A portion of the upper surface of the lever assembly  1000  (a portion of an upper or lateral surface of each lever constituting the lever assembly) forms the spoiler  130 L,  130 R. Each spoiler  130 L,  130 R reacts to wind or air stream impinging against the wiper blade  100  during running of a motor vehicle and produces a reaction force preventing the wiper blade  100  from being lifted. Such a reaction force is produced by interaction between wind or air stream and a contour of a cross-section (hereinafter referred to as a “cross-sectional profile”) of the spoiler  130 L,  130 R. The cross-sectional profile may be constant or may vary (e.g. diminish or enlarge) in the longitudinal direction of the lever assembly  1000 . That is, the cross-sectional profile may be constant in the longitudinal direction of the lever assembly  1000  or may diminish in width and height dimensions toward a distal end of the wiper blade  100 . Further, the cross-sectional profile may be symmetrical or asymmetrical in a width direction of the lever assembly (in a direction perpendicular to the longitudinal direction of the wiper rubber). In this embodiment, as shown in  FIGS. 6 and 7 , the cross-sectional profile of the spoiler  130 L,  130 R includes a triangle with somewhat concave legs. That is, the cross-sectional profile of the spoiler  130 L,  130 R includes a pair of concave curves that are symmetrical in the width direction of the wiper rubber  110 . 
     Since a pair of the end levers  1300 L,  1300 R are joined to the central lever  1100 , each longitudinal half of the lever assembly  1000  has the same configuration. Each spoiler  130 L,  130 R comprises spoiler sections located in respective levers  1100 ,  1300 L,  1300 R of the lever assembly  1000 . The spoiler sections of the respective levers are straight adjoined one after another, i.e., they are consecutively adjoined with the spoiler sections of adjacent levers adjoining each other, thereby defining the spoiler  130 L,  130 R of the wiper blade  100 . A spoiler portion included in each lever forms each corresponding spoiler section. Further, a portion of the upper surface of the lever, specifically a portion of a lateral surface of the lever, more specifically a portion or the entirety of the lateral surface of the spoiler portion forms the corresponding spoiler section. In the below descriptions on the wiper blade  100  according to the first embodiment, regarding the spoiler  130 L,  130 R integrally formed in the lever assembly  1000 , a spoiler section integrated in the central lever  1100  to become a section of the spoiler  130 L,  130 R is referred to as a central spoiler  131 L,  131 R, while a spoiler section integrated in the end lever  1300 L,  1300 R to become another section of the spoiler  130 L,  130 R is referred to as an end spoiler  133 L,  133 R. 
     The central lever  1100  is releasably coupled to the distal end of the wiper arm. Referring to  FIGS. 10 to 13 , the central lever  1100  includes a bracket portion  1110  at its middle. Further, the central lever  1100  includes a pair of central spoiler portions  1120  that extend from the bracket portion  1110  in opposite longitudinal directions (in the longitudinal direction of the wiper rubber  110 ) and form the central spoiler  131 L,  131 R respectively. 
     The bracket portion  1110  generally has a shape of a vertically-pierced rectangular parallelepiped. Fitting apertures  1111  are formed in widthwise opposing lateral walls of the bracket portion  1110  respectively. A pin or rivet  1112  (see  FIG. 25 ) is fitted to the fitting apertures  1111 . The rivet  1112  participates in connection to the wiper arm. An adaptor (not shown), which is configured to be connected to a corresponding element provided in the distal end of the wiper arm through fitting, snapping, engaging, etc., may be coupled to the rivet  1112 . The rivet  1112  may function as a pivot shaft of the wiper blade  100 . 
     A lower edge of the central lever  1100  (lower edges of the bracket portion  1110  and the central spoiler portion  1120 ) is straight or upwardly curved with slight curvature. The central spoiler portion  1120  has an inverted V-shaped cross-section. The central spoiler portion  1120  has a pair of inclined surfaces  1121 F,  1121 R that are symmetrical in the width direction of the central lever  1100 . The inclined surfaces  1121 F,  1121 R are located in the lateral surfaces of the central spoiler portion  1120 . The inclined surfaces  1121 F,  1121 R extend in the longitudinal direction of the wiper rubber  110  in the central lever  1100  and form the lateral surfaces of the central spoiler portion  1120 . Accordingly, the central spoiler  131 L,  131 R is integrated in the central lever  1100  through the central spoiler portion  1120  having the inclined surfaces  1121 F,  1121 R. An apex portion  1122  interconnects the inclined surfaces  1121 F,  1121 R at their upper edges. 
     The inclined surfaces  1121 F,  1121 R may include a flat, concave or convex surface. In this embodiment, the inclined surfaces  1121 F,  1121 R are concave. A width of the apex portion  1122  becomes sharply narrow from the bracket portion  1110  and is then constant. The inclined surfaces  1121 F,  1121 R are concave in harmony with such a width of the apex portion  1122 . Thus, the cross-sectional profile of the central spoiler  131 L,  131 R, which the inclined surfaces  1121 F,  1121 R of the central spoiler portion  1120  define, is generally a triangle with both concave legs. The central spoiler portion  1120  has a stepped surface  1124  that is further inward than a longitudinal outer end portion  1123 . The stepped surface  1124  is inclined at an acute angle toward the center of the central lever  1100 . The longitudinal outer end portion  1123  has width and height dimensions less than those of the central spoiler portion  1120 . Further, the central lever  1100  has a joint portion  1125  extending from the longitudinal outer end portion  1123  of the central spoiler portion  1120 . The joint portion  1125  has an inverted U-shaped cross-section and has width and height dimensions less than those of the outer end portion  1123 . Further, the central spoiler portion  1120  has an arm receiving portion  1126  that receives a portion of the end lever  1300 L,  1300 R and hides the same therein. The arm receiving portion  1126  is defined by a space between the inclined surfaces  1121 F,  1121 R and an interior space of the joint portion  1125 . The joint portion  1125  has a slit  1127  at its top and indentations  1128  at its lower edge. A positioning protrusion of a joint cover (this will be described below) is inserted to the slit  1127  of the joint portion and the slit  1127  participates in positioning the joint cover. A claw of the joint cover (this will be described below) engages the indentation  1128  of the joint portion, thereby preventing separation of the joint cover. 
     Each end lever  1300 L,  1300 R is joined to the central lever  1100  and holds the wiper rubber assembly  110 ,  120 . Descriptions are made as to the end lever  1300 L with reference to  FIGS. 14 to 18 . The end lever  1300 R and the end lever  1300 L are symmetrical in the longitudinal direction of the lever assembly  1000 . The end lever  1300 L,  1300 R includes an end arm  1310  to be situated in the arm receiving portion  1126  of the central spoiler portion  1120  and an end spoiler portion  1320  oppositely extending from the end arm  1310 . The end arm  1310  has an inverted U-shaped cross-section. The end spoiler portion  1320  has an inverted V-shaped cross-section. The end arm  1310  extends from a longitudinal inner end portion  1323  of the end spoiler portion  1320  toward the central lever  1100 . A lower edge of the end arm  1310  and a lower edge of the end spoiler portion  1320  form an approximately straight line. 
     The end spoiler  133 L,  133 R is integrally formed in the end spoiler portion  1320  of the end lever  1300 L,  1300 R. The end spoiler portion  1320  has a pair of inclined surfaces  1321 F,  1321 R that are symmetrical in the width direction of the end lever  1300 L,  1300 R. The inclined surfaces  1321 F,  1321 R are located in the lateral surfaces of the end spoiler portions  1320 . The inclined surfaces  1321 F,  1321 R extend in the longitudinal direction of the wiper rubber  110  in the end lever  1300 L,  1300 R and form the lateral surfaces of the end spoiler portion  1320 . Accordingly, the end spoiler  133 L,  133 R is integrated in the end lever  1300 L,  1300 R through the end spoiler portion  1320  having the inclined surfaces  1321 F,  1321 R. An apex portion  1322  interconnects the inclined surfaces  1321 F,  1321 R at their upper edges. The inclined surfaces  1321 F,  1321 R may include a flat, concave or convex surface. In this embodiment, the inclined surfaces  1321 F,  1321 R are concave in the width direction of the end lever  1300 L,  1300 R. Further, a height dimension of the inclined surfaces  1321 F,  1321 R decreases gradually toward the distal end of the wiper blade  100 . Further, lower edges of the inclined surfaces  1321 F,  1321 R approach each other at the distal end of the end lever  1300 L,  1300 R, thereby forming a round distal end of the end lever  1300 L,  1300 R along with the apex portion  1322 . The inclined surfaces  1321 F,  1321 R of the end spoiler portion  1320  may be curved with the same curvature as that of the inclined surfaces  1121 F,  1121 R of the central spoiler portion  1120 , or curved with a curvature varying therefrom. In this embodiment, the inclined surfaces  1321 F,  1321 R of the end spoiler portion  1320  is curved with the same curvature as that of the inclined surfaces  1121 F,  1121 R at the stepped surface  1124  of the central spoiler portion  1120 . 
     Each end lever  1300 L,  1300 R has two clamps  1311 ,  1325  for holding the wiper rubber assembly  110 ,  120 . A longitudinal inner clamp  1311  is formed at a distal end of the end arm  1310 . A longitudinal outer clamp  1325  is formed at a lower edge of the end spoiler portion  1320  in the vicinity of a longitudinal outer end thereof. 
     As shown in  FIG. 17 , the clamp  1311  has a generally rectangular cross-section with its bottom side cut away partially and thus both ends thereof extend inwardly. When the end lever  1300 L,  1300 R is coupled to the wiper rubber assembly  110 ,  120 , an upper inner surface of the clamp  1311  is placed on a top side of the wiper rubber  110  and lateral portions of the clamp  1311  sandwich the spring rail  120  and a portion of the wiper rubber  110  adjacent thereto and the both ends of the clamp  1311  are inserted to the second groove  114 . 
     Referring to  FIGS. 14 and 18 , the clamp  1325  extends from the lower edge of the end spoiler portion  1320  in a V shape. Both ends of the clamp  1325  are inserted to the second groove  114  of the wiper rubber  110 . A longitudinal outer surface  1325   a  of the clamp  1325  is inclined longitudinally outwardly, while a longitudinal inner surface  1325   b  is inclined longitudinally inwardly. A portion of the end lever  1300 L,  1300 R, at which the clamp  1325  is located, is hollow. To ensure fixation between the clamp  1325  and the wiper rubber  110 , a clamp insert  1330  is fitted to the clamp  1325 . The clamp insert  1330  is intervened between the wiper rubber  110  and the portion of the end lever  1300 L,  1300 R where the clamp  1325  is located. That is, as shown in  FIG. 14 , the lever assembly  1000  has the clamp insert  1330  that is fitted to the clamp  1325  of the end lever  1300 L,  1300 R to fix the wiper rubber assembly  110 ,  120  to the clamp  1325 .  FIGS. 16 to 18  do not show the clamp insert  1330  to clearly depict the interior of the end lever. 
     Reference is made to  FIGS. 19 to 24  and descriptions are made as to the clamp insert  1330 . The clamp insert  1330  is shaped to mate with a cross section formed by the inclined surfaces  1321 F,  1321 R, the apex portion  1322  and the clamp  1325  in the end lever  1300 L,  1300 R. Further, the clamp insert  1330  is configured to snap-engage the clamp  1325  and sandwich or pinch the wiper rubber  110 . The clamp insert  1330  has a body portion  1331 , a pair of sandwiching portions  1332  located beside the body portion  1331  and coupled to the clamp  1325 , and a pressing portion  1333  formed in the body portion  1331  to abut or press the top side of the wiper rubber  110 . The body portion  1331  extends in the longitudinal direction of the end lever  1300 L,  1300 R. On a top side of the body portion  1331  is formed a longitudinally-extending head portion  1334 , which contacts the inner surface of the apex portion  1322  of the end lever or is positioned with a slight gap therebetween. A sandwiching space  1338 , in which an upper portion of the wiper rubber  110  is received, is defined between the body portion  1331  and the sandwiching portion  1332 . 
     The sandwiching portion  1332  is formed in a rib portion  1335  extending the top side of the body portion  1331 . Thus, the sandwiching portion  1332  can snap-engage the clamp  1325  through the rib portion  1335  elastically bending inwardly and outwardly of the body portion  1331 . The sandwiching portion  1332  extends in the longitudinal direction of the body portion  1331 . Claws  1336 ,  1337  are formed at longitudinal inner and outer ends of the sandwiching portion  1332  respectively. The longitudinal outer claw  1336  engages the longitudinal outer surface  1325   a  of the clamp  1325 . A longitudinally leading end of the outer claw  1336  is inwardly inclined for easy insertion of the clamp insert  1330  to the clamp  1325 . The longitudinal inner claw  1337  engages the longitudinal inner surface  1325   b  of the clamp  1325 . Further, a longitudinal inner surface of the outer claw  1336  and a longitudinal outer surface of the inner claw  1337  are inclined to correspond to the longitudinal outer surface  1325   a  and the longitudinal inner surface  1325   b  of the clamp  1325  respectively. 
     At least a portion of the body portion  1331  protrudes downwardly to thus form the pressing portion  1333 . The pressing portion  1333  is formed to be located above the both ends of the clamp  1325  when the clamp insert  1330  is fitted to the clamp  1325 . An underside of the pressing portion  1333  is placed on or abuts the top side of the wiper rubber  110 , thereby fixing the wiper rubber  110  to the clamp  1325  or pressing the wiper rubber against the both ends of the clamp  1325 . 
       FIGS. 23 and 24  depict an example coupling between the end lever  1300 L,  1300 R and the clamp insert  1330 . As shown in  FIG. 23 , the clamp insert  1330  snap-engages the clamp  1325  through insertion. The clamp insert  1330  is situated inside the end lever  1330 L,  1300 R and then is pushed toward the clamp  1325 . Then, the outer claw  1326  is brought into abutment with the inner surface  1325   b  of the clamp  1325 . Since the sandwiching portion  1332  may be pushed toward the body portion  1331  via the rib portion  1335 , the outer claw  1336  of the clamp insert  1330  can pass the clamp  1325 . If the clamp insert  1330  is fitted to the clamp  1325 , then the longitudinal outer and inner surfaces  1325   a ,  1325   b  of the clamp  1325  are between the outer claw  1336  and the inner claw  1337  of the clamp insert  1330 . As shown in  FIG. 24 , when the lever assembly  1000  and the wiper rubber assembly  110 ,  120  are coupled to each other, the pressing portion  1333  of the clamp insert  1330  presses the top side of the wiper rubber  110  downwardly (toward the both ends of the clamp  1325 ). Alternatively, the pressing portion  1333  of the clamp insert  1330  is placed on the top side of the wiper rubber  110  with little gap. Thus, the wiper rubber  110  is firmly fixed to the clamp  1325  via the clamp insert  1330 . 
     The central lever  1100  and the end lever  1300 L,  1300 L are joined to each other via hinge-joint. When the central lever  1100  and the end lever  1300 L,  1300 R are joined to each other, the end arm  1310  of the end lever is situated in the arm receiving portion  1126  of the central spoiler portion  1120  and is thus hidden within the central spoiler portion  1120  when viewed from outside. In other words, in the lever assembly  1000 , a portion (e.g., the end arm  1310 ) of one of the adjacent levers (e.g., the end lever  1300 L,  1300 R) is inside the spoiler portion of the other of the adjacent levers (e.g., the central lever  1100 ), which is further inward than said one of the adjacent levers. The central lever  1100  and the end lever  1300 L,  1300 R are joined to each other through a hinge-joint portion  1400 L,  1400 R penetrating through both the joint portion  1125  of the central lever and the end arm  1310  of the end lever. The hinge-joint portion  1400 L,  1400 R may include, but is not limited to, a rivet joint or pin joint. In this embodiment, the hinge-joint portion  1400 L,  1400 R includes a rivet joint. 
     Referring to  FIG. 25 , the hinge-joint portion  1400 L,  1400 R includes a rivet  1410  serving as a hinge shaft and a hinge insert  1420  coupled to the rivet  1410 . Through apertures  1126  for hinge-joint are formed in the joint portion  1125  of the central lever  1100  in a width direction thereof. Also, through apertures  1312  are formed in a portion of the end arm  1310  corresponding to the joint portion  1125  in a width direction thereof. Referring to  FIGS. 26 and 27 , the hinge insert  1420  has an inverted U-shaped cross-section. The hinge insert  1420  has through apertures  1421  in its opposing lateral portions. Further, the hinge insert  1420  has a widthwise-oriented slit  1422  in its top and indentations  1423  at its lower edge. The slit  1422  and the indentation  1423  correspond to the slit  1127  and the indentation  1128  of the joint portion  1125  of the central lever respectively. 
     The hinge insert  1420  is nested on the end arm  1310  such that the through apertures  1421  and the through apertures  1312  are in alignment with each other. Thereafter, the joint portion  1125  of the central lever  1100  is nested on the hinge insert  1420  such that its through apertures  1126  are aligned with the through apertures  1421 . The rivet  1410  is pierced through the through apertures  1126 ,  1421 ,  1312  and then riveted thereto, thus forming the hinge-joint portion  1400 L,  1400 R. 
     Referring to  FIG. 25 , when the central lever  1100  and the end lever  1300 L,  1300 R are joined to each other, the joint portion  1125  of the central lever  1100  is nested on the end arm  1310  of the end lever  1300 L,  1300 R with the hinge insert  1420  therebetween and the hinge-joint portion  1400 L,  1400 R is formed between the central lever  1100  and the end lever  1300 L,  1300 R. The lever assembly  1000  includes a joint cover  1430 , which is disposed between the central lever  1100  and the end lever  1300 L,  1300 R to cover the hinge-joint portion  1400 L,  1400 R. 
     Referring to  FIGS. 28 and 29 , the joint cover  1430  has an inverted V-shaped cross-section. The joint cover  1430  has a pair of inclined surfaces  1431 F,  1431 R symmetrical in a width direction thereof. An apex portion  1432  interconnects the inclined surfaces  1431 F,  1431 R. The inclined surface  1431 F,  1431 R is concave. A curvature of the inclined surface  1431 F,  1431 R is equal to those of the inclined surface  1121 F,  1121 R of the central spoiler portion and the inclined surfaces  1321 F,  1321 R of the end spoiler portion. A height dimension of the inclined surface  1431 F,  1431 R decreases gradually from a longitudinal inner end  1435  toward a longitudinal outer end  1436 . A cross-sectional profile of the joint cover  1430  corresponds to both the cross-sectional profile of the central spoiler portion  1120  and the cross-sectional profile of the end spoiler portion  1320 . That is, the cross-sectional profile of the joint cover  1430  decreases gradually in its height dimension toward the distal end of the lever assembly  1000 . The joint cover  1430  has the cross-section profile achieving such decrease. In this embodiment, the cross-sectional profile of the joint cover  1430  includes a triangle having concave legs. 
     The longitudinal inner end  1435  is inclined at the same angle as the stepped surface  1124  of the central spoiler portion  1120  and is capable of contacting the stepped surface  1124  of the central spoiler portion  1120 . The longitudinal outer end portion  1123  of the central spoiler portion  1120  is situated within the inclined surfaces  1431 F,  1431 R of the joint cover. Further, the longitudinal outer end  1436  is inclined at the same angle as a stepped surface  1324  of the end spoiler portion  1430  and is capable of contacting the stepped surface  1324  of the end spoiler portion  1320 . The joint cover  1430  snap-engages the joint portion  1125  of the central lever. The joint cover  1430  has a protrusion or claw  1433  protruding from a lower inner surface of the inclined surface  1431 F,  1431 R. The claw  1433  snap-engages the indentation  1128  of the joint portion  1125 . Further, the joint cover  1430  has a pair of positioning protrusions  1434  protruding from a lower surface of the apex portion  1432 . The positioning protrusions  1434  are inserted to the slit  1127  of the joint portion  1125 . 
     The stepped surface  1124  of the central lever  1100  is inclined at an acute angle inwardly of the wiper blade  100 , while the stepped surface  1324  of the end lever  1300 L,  1300 R is inclined at an acute angle toward the distal end of the wiper blade  100 . Further, the longitudinal inner end  1435  and outer end  1436  of the joint cover  1430  are inclined in harmony with such inclination of the stepped surfaces. Thus, when no load acts on the wiper blade  100 , the central spoiler portion  1120 , the joint cover  1430  and the end spoiler portion  1320  can become open with some gap therebetween. On the contrary, when a downward load acts on the wiper blade  100  (e.g., when the wiper arm applies a force to the wiper blade toward the windshield), the central spoiler portion  1120 , the joint cover  1430  and the end spoiler portion  1320  are brought into close abutment with one another in the longitudinal direction of the lever assembly  1000 . That is, with the stepped surfaces  1124 ,  1423  inclined as described above and the shape of the joint cover  1430  corresponding thereto, the end lever  1300 L,  1300 R cannot pivot upwardly relative to the central lever  1100 . Accordingly, when a downward load acts on the wiper blade  100 , the lever assembly  1000  can bring the wiper rubber  110  into strong contact with the windshield along its entire length. 
     Descriptions are made as to an example assembly of the wiper blade  100  according to the first embodiment with reference to  FIG. 25 . 
     In an assembly wherein the central lever  1100  and the end levers  1300 L,  1300 R are hinge-jointed to each other, the joint cover  1430  is snap-engaged to the joint portion  1125  of the central lever. By pressing the joint cover  1430  against the joint portion  1125 , the claws  1433  of the joint cover  1430  snap-engage the indentations  1128  of the joint portion  1125  and the positioning protrusions  1434  of the joint cover  1430  are inserted to the slit  1127  of the joint portion  1125 , thus coupling the joint cover  1430  to the joint portion  1125  and thereby completing the lever assembly  1000 . 
     By fitting the clamps  1325 ,  1311  of the end levers  1300 L,  1300 R to the second groove  114  of the wiper rubber  110 , the lever assembly  1000  and the wiper rubber assembly  110 ,  120  are coupled to each other. First, the both ends of the clamp  1325  of the end lever  1300 L with the clamp insert  1330  fitted thereto are positioned in the second groove  114  of the wiper rubber  110  and then the wiper rubber assembly  110 ,  120  is slid along the lever assembly  1000 . Subsequently, the both ends of the clamps  1311  of the end lever  1300 L are positioned in the second groove  114  and then the wiper rubber assembly  110 ,  120  is slid along the lever assembly  1000 . Thereafter, the clamps  1311 ,  1325  of the end lever  1300 R is positioned in the second groove  114  one after the other, and the wiper rubber assembly  110 ,  120  is slid along the lever assembly  1000 . If the both ends of the clamp  1325  of the end lever  1300 L are fitted to the insertion holes  117  and the sandwiching portions  1332  of the clamp insert  1330  are placed in the recess  116 , then the wiper rubber assembly  110 ,  120  is fixed to the lever assembly  1000 . 
     Referring again to  FIGS. 1 to 5  showing the assembled wiper blade  100 , the lever assembly  1000  holds and supports the wiper rubber assembly  110 ,  120  at four positions (i.e., at four pressure points) via the clamps  1325 ,  1311  of the end lever  1300 L,  1300 R. Further, the central lever  1100  and the end levers  1300 L,  1300 R are straight arranged along the length of the wiper rubber  110  and are at the same height on the wiper rubber  110 . Further, in the assembled wiper blade  100 , the inclined surfaces  1121 F,  1121 R of the central spoiler portion  1120 , the inclined surfaces  1431 F,  1431 R of the joint cover  1430  and the inclined surfaces  1321 F,  1321 R of the end spoiler portion  1320  are straight adjoined one after another, thereby defining the spoiler  130 L,  130 R with the cross-sectional profile varying in the longitudinal direction. 
       FIGS. 30 to 43  show a wiper blade according to a second embodiment, generally denoted by  200 , and elements or components constituting the wiper blade  200 . The wiper blade  200  according to this embodiment is configured to hold the wiper rubber at six pressure points. The wiper blade  200  has a longer length when compared to the wiper blade  100  according to the first embodiment and its lever assembly has a configuration for the longer length. In  FIGS. 30 to 43 , the same elements or components as those of the wiper blade  100  of the first embodiment are denoted by the same reference numerals. 
     Referring to  FIGS. 30 to 43 , the wiper blade  200  according to the second embodiment has a wiper rubber  210 , which contacts the windshield surface, and a lever assembly  2000  holding and supporting the wiper rubber  210 . Further, the wiper blade  200  includes a pair of spoilers  230 L,  230 R that produce a reaction force preventing the lift caused by wind or air stream. The left spoiler  230 L and the right spoiler  230 R are symmetrical relative to a longitudinal center of the wiper rubber  210 . The spoilers  230 L,  230 R are integrated in the lever assembly  2000  and extend in the longitudinal direction of the wiper rubber  210 . 
     The wiper rubber  210  has the same configuration as that of the wiper rubber  110  of the first embodiment and has a length longer than the wiper rubber  110 . Spring rails  220  are inserted to the first grooves  113  to thus impart rigidity to the wiper rubber  210  (see  FIG. 43 ). Hereinafter, the wiper rubber  210  with the spring rails  220  fitted thereto is referred to as a wiper rubber assembly  210 ,  220 . 
     The lever assembly  2000  connects the wiper rubber assembly  210 ,  220  to the wiper arm and supports the wiper rubber assembly  210 ,  220  with respect to the wiper arm. The wiper blade  200  is coupled to the wiper arm in such a manner that the lever assembly  2000  is releasably joined to the distal end of the wiper arm. In this embodiment, the lever assembly  2000  includes a central lever  1100  centrally located in the wiper rubber assembly  210 ,  220 , a pair of intermediate levers  2200 L,  2200 R joined to the central lever  1100  respectively and a pair of end levers  2300 L,  2300 R joined to the intermediate lever  2200 L,  2200 R respectively. The levers  1100 ,  2200 L,  2200 R,  2300 L,  2300 R constituting the lever assembly  2000  are straight arranged along a longitudinal direction of the wiper rubber  210 . The adjacent levers are hinge-jointed to each other. The levers  1100 ,  2200 L,  2200 R,  2300 L,  2300 R have an elongated hollow shape and may be made by pressing a metallic sheet or injection molding a plastic material. 
     Similar to the first embodiment, a cross-sectional profile of the spoiler  230 L,  230 R for producing the reaction force includes a triangle having concave legs. The cross-sectional profile of the spoiler  230 L,  230 R decreases gradually in a height dimension toward a distal end of the wiper blade  200 . Each spoiler  230 L,  230 R comprises spoiler sections located in the respective levers  1100 ,  2200 L,  2200 R,  2300 L,  2300 R. The spoiler sections of the respective levers are straight adjoined one after another, i.e. they are consecutively adjoined with the spoiler sections of adjacent levers adjoining each other, thereby defining the spoiler  230 L,  230 R. As described below regarding the spoiler  230 L,  230 R integrated in the lever assembly  2000 , a spoiler section integrated in the central lever  1100  is referred to as a central spoiler  131 L,  131 R, and another spoiler section integrated in the intermediate lever  2200 L,  2200 R is referred to as an intermediate spoiler  232 L,  232 R, and yet another spoiler section integrated in the end lever  2300 L,  2300 R is referred to as an end spoiler  233 L,  233 R. 
     Each intermediate lever  2200 L,  2200 R is joined to the central lever  1100  and holds the wiper rubber assembly  210 ,  220 . Descriptions are made as to the intermediate lever  2200 L with reference to  FIGS. 35 to 38 . The intermediate lever  2200 L and the intermediate lever  2200 R are symmetrical in the longitudinal direction of the lever assembly  2000 . The intermediate lever  2200 L,  2200 R includes an intermediate arm  2210  to be situated in the arm receiving portion  1126  of the central spoiler portion  1120  and an intermediate spoiler portion  2220  oppositely extending from the intermediate arm  2210 . The intermediate arm  2210  has an inverted U-shaped cross-section. The intermediate spoiler portion  2220  has an inverted V-shaped cross-section. The intermediate arm  2210  extends from a longitudinal inner end portion  2223  of the intermediate spoiler portion  2220  toward the central lever  1100 . A lower edge of the intermediate arm  2210  and a lower edge of the intermediate spoiler portion  2220  form an approximately straight line. 
     Each intermediate lever  2200 L,  2200 R has a clamp  2211  for fixing the wiper rubber assembly  210 ,  220 . The clamp  2211  is formed at a distal end of the intermediate arm  2210 . The clamp  2211  has the same shape as the clamp  1311  of the first embodiment. When the intermediate lever  2200 L,  2200 R and the wiper rubber assembly  210 ,  220  are coupled to each other, both ends of the clamp  2211  is inserted to the second groove  114  of the wiper rubber  210 . 
     The intermediate spoiler  232 L,  232 R is integrally formed in the intermediate spoiler portion  2220 . The intermediate spoiler portion  2220  has a pair of inclined surfaces  2221 F,  2221 R that are symmetrical in the width direction of the intermediate lever  2200 L,  2200 R. The inclined surfaces  2221 F,  2221 R are located in the lateral surfaces of the intermediate spoiler portion  2220 . The inclined surfaces  2221 F,  2221 R extend in the longitudinal direction of the wiper rubber  210  in the intermediate lever  2200 L,  2200 R and form the lateral surfaces of the intermediate spoiler portion  2220 . Accordingly, the intermediate spoiler  232 L,  232 R is integrated in the intermediate lever  2200 L,  2200 R through the intermediate spoiler portion  2220  having the inclined surfaces  2221 F,  2221 R. An apex portion  2222  interconnects the inclined surfaces  2221 F,  2221 R at their upper edges. The inclined surfaces  2221 F,  2221 R are concave in the width direction of the intermediate lever  2200 L  2200 R. Further, a height dimension of the inclined surfaces  2221 F,  2221 R decrease gradually toward the longitudinal outer end of the intermediate lever  2200 L,  2200 R. The inclined surfaces  2221 F,  2221 R of the intermediate spoiler portion  2220  may be curved with the same curvature as that of the inclined surfaces  1121 F,  1121 R of the central spoiler portion  1120 , or curved with a curvature varying therefrom. In this embodiment, the inclined surfaces  2221 F,  2221 R of the intermediate spoiler portion  2220  is curved with the same curvature as that of the inclined surfaces  1121 F,  1121 R at the stepped surface  1124  of the central spoiler portion  1120 . The curvature of the inclined surface  2221 F,  2221 R is constant in the longitudinal direction of the intermediate spoiler portion  2220 . 
     The central lever  1100  and the intermediate lever  2200 L,  2200 R are joined to each other via a hinge-joint portion  2400 L,  2400 R penetrating through the joint portion  1125  and the intermediate arm  2210 . When the central lever  1100  and the intermediate lever  2200 L,  2200 R are joined to each other, the intermediate arm  2210  of the intermediate lever is situated in the arm receiving portion  1126  of the central spoiler portion  1120  and is thus hidden within the central spoiler portion  1120  when viewed from outside. In other words, a portion (e.g., the intermediate arm  2210 ) of one of the adjacent levers (e.g., the intermediate lever  2200 L,  2200 R) is inside the spoiler portion of the other of the adjacent levers (e.g., the central lever  1100 ), which is further inward than said one of the adjacent levers. 
     The hinge-joint portion  2400 L,  2400 R between the central lever  1100  and the intermediate lever  2200 L,  2200 R has the same configuration as the hinge-joint portion  1400 L,  1400 R of the first embodiment. Referring to  FIG. 43 , the hinge-joint portion  2400 L,  2400 R includes the rivet  1410  serving as a hinge shaft and the hinge insert  1420  coupled to the rivet  1410 . Through apertures  2212   a  for hinge-joint are formed in a portion of the intermediate arm  2210 , which corresponds to the joint portion  1125  of the central lever  1100 , in a width direction thereof. The hinge insert  1420  is nested on the intermediate arm  2210  such that the through apertures  1421  and the through apertures  2212   a  are in alignment with each other. Thereafter, the joint portion  1125  of the central lever  1100  is nested on the hinge insert  1420  such that the through apertures  1126  are aligned with the through apertures  1421 . The rivet  1410  is pierced through the through apertures  1126 ,  1421 ,  2212   a  and then riveted thereto, thus forming the hinge-joint portions  2400 L,  2400 R. 
     The intermediate lever  2200 L,  2200 R includes a joint portion  2227 , which extends from a longitudinal outer end portion  2225  of the intermediate spoiler portion  2220  toward the distal end of the wiper blade  200  and has an inverted U-shaped cross section. The joint portion  2227  has width and height dimensions less than the longitudinal outer end portion  2225  of the intermediate spoiler portion  2220 . The intermediate spoiler portion  2220  has an arm receiving portion  2226  receiving a portion of the end lever  2300 L,  2300 R. The arm receiving portion  2226  is defined by a space between the inclined surfaces  2221 F,  2221 R and an interior space of the joint portion  2227 . The joint portion  2227  participates in hinge-joint to the end lever  2300 L,  2300 R. The joint portion  2227  has a slit  2228  at its top and indentations  2229  at its lower edge. The slit  2228  and the indentations  2229  participate in engagement with the joint cover  1430 ′. 
     The end levers  2300 L,  2300 R are joined to the intermediate levers  2200 L,  2200 R respectively and hold the wiper rubber assembly  210 ,  220 . The end lever  2300 L,  2300 R according to this embodiment has the same configuration as the end lever  1300 L, l 300 R of the first embodiment. Further, the end lever  2300 L,  2300 R has a length shorter than the end lever  1300 L,  1300 R of the first embodiment. 
     Descriptions are made as to the end lever  2300 L with reference to  FIGS. 39 to 42 . The end lever  2300 L and the end lever  2300 R are symmetrical in the longitudinal direction of the lever assembly  2000 . The end lever  2300 L,  2300 R includes an end arm  2310  to be situated in the arm receiving portion  2226  of the intermediate spoiler portion  2220  and an end spoiler portion  2320  oppositely extending from the end arm  2310 . The end arm  2310  has an inverted U-shaped cross-section. The end spoiler portion  2320  has an inverted V-shaped cross-section. The end arm  2310  extends from a longitudinal inner end portion  2323  of the end spoiler portion  2320  toward the intermediate lever  2200 L,  2200 R. A lower edge of the end arm  2310  and a lower edge of the end spoiler portion  2320  form an approximately straight line. The inner end portion  2323  has width and height dimensions less than the longitudinally inner stepped surface  2324  of the end spoiler portion  2320 . Two clamps  2325 ,  2311  of each end lever  2300 L,  2300 R fix the wiper rubber assembly  210 ,  220 . The clamp  2325  is formed at a lower edge of the end spoiler portion  2320  in the vicinity of its longitudinal outer end. The clamp  2311  is formed at a distal end of the end arm  2310 . The clamps  2311 ,  2325  have the same shape as the clamps  1311 ,  1325  of the end lever  1300 L,  1300 R of the first embodiment. As shown in  FIG. 39 , the clamp insert  1330  of the first embodiment is fitted to the clamp  2325  to fix the wiper rubber  210  to the clamp  2325 . 
     The end spoiler portion  2320  has a pair of inclined surfaces  2321 F,  2321 R that are symmetrical in the width direction of the end lever  2300 L,  2300 R. The inclined surfaces  2321 F,  2321 R are located in the lateral surfaces of the end spoiler portions  2320 . The inclined surfaces  2321 F,  2321 R extend in the longitudinal direction of the wiper rubber  210  in the end lever  2300 L,  2300 R and form the lateral surfaces of the end spoiler portion  2320 . Accordingly, the end spoiler  233 L,  233 R is integrated in the end lever  2300 L,  2300 R through the end spoiler portion  2320  having the inclined surfaces  2321 F,  2321 R. An apex portion  2322  interconnects the inclined surfaces  2321 F,  2321 R at their upper edges. The inclined surfaces  2321 F,  2321 R are concave in the width direction of the end lever  2300 L,  2300 R. Further, a height dimension of the inclined surfaces  2321 F,  2321 R decreases gradually toward the longitudinal outer end of the end lever  2300 L,  2300 R. Further, lower edges of the inclined surfaces  2321 F,  2321 R approach each other at the distal end of the end lever  2300 L,  2300 R, thereby forming a round distal end of the end lever  2300 L,  2300 R along with the apex portion  2322 . The inclined surfaces  2321 F,  2321 R may be curved with the same curvature as that of the inclined surfaces  2221 F,  2221 R of the intermediate spoiler portion  2220 , or curved with a curvature varying therefrom. In this embodiment, the inclined surfaces  2321 F,  2321 R of the end spoiler portion  2320  is curved with a curvature greater than that of the inclined surfaces  2221 F,  2221 R of the intermediate spoiler portion. 
     The intermediate lever  2200 L,  2200 R and the end lever  2300 L,  2300 R are joined to each other via a hinge-joint portion  2400 ′L,  2400 ′R penetrating through the joint portion  2227  of the intermediate lever and the end arm  2310  of the end lever. When the intermediate lever  2200 L,  2200 R and the end lever  2300 L,  2300 R are joined to each other, the end arm  2310  is situated in the arm receiving portion  2226  of the intermediate spoiler portion  2220  and is thus hidden within the intermediate spoiler portion  2220  when viewed from outside. 
     Referring to  FIG. 43 , when the central lever  1100  and the intermediate lever  2200 L,  2200 R are joined to each other, the joint portion  1125  of the central lever  1100  is nested on the intermediate arm  2210  of the intermediate lever  2200 L,  2200 R with the hinge insert  1420  intervened therebetween and the hinge-joint portion  2400 L,  2400 R is formed therebetween. Further, when the intermediate lever  2200 L,  2200 R and the end lever  2300 L,  2300 R are joined to each other, the joint portion  2227  of the intermediate lever  2200 L,  2200 R is nested on the end arm  2310  of the end lever  2300 L,  2300 R with the hinge insert  1420  intervened therebetween and the hinge-joint portion  2400 ′L,  2400 ′R is formed therebetween. The lever assembly  2000  includes the joint covers  1430 ,  1430 ′ disposed between the levers to cover the hinge-joint portions  2400 L,  2400 R,  2400 ′L,  2400 ′R. The joint cover  1430  snap-engages the joint portion  1125  of the central lever between the central lever  1100  and the intermediate lever  2200 L,  2200 R. The joint cover  1430 ′ snap-engages the joint portion  2227  of the intermediate lever between the intermediate lever  2200 L,  2200 R and the end lever  2300 L,  2300 R. The joint cover  1430 ′ has a configuration similar to the configuration of the joint cover  1430 . A cross-sectional profile of the joint cover  1430 ′ decreases in height dimension toward the end lever  2300 L,  2300 R. Further, a curvature of the inclined surface  1431 F,  1431 R of the joint cover  1430 ′ increases toward the end lever  2300 L,  2300 R. 
     The stepped surface  1124  of the central spoiler portion  1120  and a stepped surface  2224   b  of the intermediate spoiler portion  2220  are inclined at an acute angle inwardly of the wiper blade  200 , while a stepped surface  2224   a  of the intermediate spoiler portion  2220  and a stepped surface  2324  of the end spoiler portion  2320  are inclined at an acute angle toward the distal end of the wiper rubber  210 . Further, the longitudinal both ends of the joint covers  1430 ,  1430 ′ are inclined in harmony with such inclination of the stepped surfaces. Thus, when no load acts on the wiper blade  200 , the central spoiler portion  1120 , the joint cover  1430 , the intermediate spoiler portion  2220 , the joint cover  1430 ′ and the end spoiler portion  2320  can become open with a slight gap therebetween. With the stepped surfaces  1124 ,  2224   a ,  2224   b ,  2324  inclined as described above and the shapes of the joint covers  1430 ,  1430 ′ corresponding thereto, the intermediate lever  2200 L,  2200 R and the end lever  2300 L,  2300 R cannot pivot upwardly relative to the central lever  1100 . Accordingly, when a downward load acts on the wiper blade  200 , the central spoiler portion  1120 , the joint cover  1430 , the intermediate spoiler portion  2220 , the joint cover  1430 ′ and the end spoiler portion  2320  is brought into close abutment with one another in the longitudinal direction, thereby bringing the wiper rubber  210  into strong contact with the windshield. 
     Descriptions are made as to an example assembly of the wiper blade  200  according to the second embodiment with reference to  FIG. 43 . 
     In an assembly wherein the central lever  1100 , the intermediate lever  2200 L,  2200 R and the end lever  2300 L,  2300 R are hinge-jointed to one another, the joint covers  1430 ,  1430 ′ are snap-engaged to the hinge-joint portions  2400 L,  2400 R,  2400 ′L,  2400 ′R respectively by pressing the joint cover  1430  and the joint cover  1430 ′ against the joint portion  1125  of the central lever and the joint portion  2227  of the intermediate lever respectively. The claws  1433  of the joint covers  1430 ,  1430 ′ snap-engage the indentations  1128 ,  2229  of the joint portions  1125 ,  2227  and the positioning protrusions  1434  of the joint covers  1430 ,  1430 ′ are inserted to the slits  1127 ,  2228  of the joint portions  1125 ,  2227 , thus coupling the joint covers  1430 ,  1430 ′ to the hinge-joint portions  2400 L,  2400 R,  2400 ′L,  2400 ′R. 
     By fitting the clamps  2325 ,  2311  of the end levers  2300 L,  2300 R and the clamps  2211  of the intermediate levers  2200 L,  2200 R to the second groove  114  of the wiper rubber  210 , the lever assembly  2000  and the wiper rubber assembly  210 ,  220  are coupled to each other. For example, the wiper rubber assembly  210 ,  220  is slid along the lever assembly  2000  while sequentially inserting the following: the clamp  2325  of the end lever  2300 L with the clamp insert  1330  fitted thereto, the clamp  2311  of the end lever  2300 L, the clamp  2211  of the intermediate lever  2200 L, the clamp  2211  of the intermediate lever  2200 R, the clamp  2311  of the end lever  2300 R and the clamp  2325  of the end lever  2300 R with the clamp insert  1330  fitted thereto. If the both ends of the clamp  2325  of the end lever  2300 L is fitted to the insertion holes  117  and the sandwiching portions  1332  of the clamp insert  1330  are placed in the recess  116 , the wiper rubber assembly  210 ,  220  is fixed to the lever assembly  2000 . 
     Referring again to  FIGS. 30 to 34  showing the assembled wiper blade  200 , the lever assembly  2000  holds the wiper rubber assembly  210 ,  220  at six pressure points via the clamps  2325 ,  2311  of the end levers  2300 L,  2300 R and the clamps  2211  of the intermediate levers  2200 L,  2200 R. Further, the central lever  1100 , the intermediate levers  2200 L,  2200 R and the end levers  2300 L,  2300 R are straight arranged along the length of the wiper rubber  210  and are at the same height on the wiper rubber  210 . Further, in the assembled wiper blade  200 , the inclined surfaces  1121 F,  1121 R of the central spoiler portion  1120 , the inclined surfaces  1431 F,  1431 R of the joint cover  1430 , the inclined surfaces  2221 F,  2221 R of the intermediate spoiler portion  2220 , the inclined surfaces  1431 F,  1431 R of the joint cover  1430 ′ and the inclined surfaces  2321 F,  2321 R of the end spoiler portion  2320  are straight adjoined one after another, thereby defining the spoiler  230 L,  230 R having the cross-sectional profile with its height dimension decreasing toward the distal end of the wiper blade  200 . 
       FIGS. 44 to 56  show a wiper blade according to a third embodiment, generally denoted by  300 , and elements or components constituting the wiper blade  300 . The wiper blade  300  according to this embodiment is configured to hold the wiper rubber at eight pressure points. The wiper blade  300  according to the third embodiment has a longer length when compared to the wiper blades  100 ,  200  according to the first and second embodiments and its lever assembly has a configuration for such a longer length. In  FIGS. 44 to 56 , the same elements or components as those of the wiper blades  100 ,  200  of the first and second embodiments are denoted by the same reference numerals. 
     Referring to  FIGS. 44 to 46 , the wiper blade  300  according to the third embodiment has a wiper rubber  310 , which contacts the windshield surface, and a lever assembly  3000  holding and supporting the wiper rubber  310 . Further, the wiper blade  300  includes a pair of spoilers  330 L,  330 R, which produce a reaction force preventing the lift caused by wind or air stream and are symmetrical relative to a longitudinal center of the wiper rubber  310 . The spoilers  330 L,  330 R are integrated in the lever assembly  3000  and extend in the longitudinal direction of the wiper rubber  310 . 
     The wiper rubber  310  has the same configuration as those of the wiper rubbers  110 ,  210  of the first and second embodiments and has a length longer than the wiper rubbers  110 ,  210 . Spring rails  320  (see  FIG. 56 ) are inserted to the first grooves  113  of the wiper rubber  310  to thus impart rigidity to the wiper rubber  310 . The spring rail  320  has the same configuration as and a length longer than the spring rail  120  of the first embodiment. Hereinafter, the wiper rubber  310  with the spring rails  320  fitted thereto is referred to as a wiper rubber assembly  310 ,  320 . 
     In this embodiment, the lever assembly  3000 , which connects the wiper rubber assembly  310 ,  320  to the wiper arm, includes a central lever  3100 , a pair of intermediate levers  3200 L,  3200 R joined to the central lever  3100  respectively and a pair of the end levers  2300 L,  2300 R joined to the intermediate lever  2200 L,  2200 R respectively. The levers  3100 ,  3200 L,  3200 R,  2300 L,  2300 R constituting the lever assembly  3000  are straight arranged along a longitudinal direction of the wiper rubber  310 . The adjacent levers are hinge-jointed to each other. The levers  3100 ,  3200 L,  3200 R,  2300 L,  2300 R have an elongated hollow shape and may be made by pressing a metallic sheet or injection molding a plastic material 
     The spoiler  330 L,  330 R is integrated in an upper surface of the lever assembly  3000  (an upper or lateral surface of each lever constituting the lever assembly) along a longitudinal direction thereof (along a longitudinal direction of the wiper rubber  310 ). Similar to the first and second embodiments, a cross-sectional profile of the spoiler  330 L,  330 R for producing the reaction force includes a triangle having concave legs. The cross-sectional profile of the spoiler  330 L,  330 R decreases in a height dimension toward a distal end of the wiper blade  300 . Each spoiler  330 L,  330 R comprises spoiler sections located in respective levers  3100 ,  3200 L,  3200 R,  3300 L,  3300 R. The spoiler sections of the respective levers are straight adjoined one after another, i.e. they are consecutively adjoined with the spoiler sections of adjacent levers adjoining each other, thereby defining the spoiler  330 L,  330 R. A spoiler portion of each lever forms the spoiler section. Specifically, a portion or an entirety of a lateral surface of each spoiler portion forms the spoiler section. In the below descriptions, regarding the spoiler  330 L,  330 R formed in the lever assembly  3000 , a spoiler section integrated in the central lever  3100  is referred to as a central spoiler  331 L,  331 R, and another spoiler section integrated in the intermediate lever  3200 L,  3200 R is referred to as an intermediate spoiler  332 L,  332 R, and yet another spoiler section integrated in the end lever  2300 L,  2300 R is referred to as an end spoiler  233 L,  233 R. 
     The central lever  3100  is located in the middle of the wiper rubber assembly  310 ,  320 . The central lever  3100  is releasably coupled to the distal end of the wiper arm. The central lever  3100  has the same configuration as the central lever  1100  of the first embodiment. The central spoiler  331 L,  331 R integrally formed in the central lever  3100  is longer than the central spoiler  131 L,  131 R of the central lever  1100 . 
     Referring to  FIGS. 47 and 48 , the central lever  3100  includes a pair of central spoiler portions  3120 , which extend from the centrally-located bracket portion  1110  in opposite directions in the longitudinal direction of the wiper rubber  310  and define the central spoiler  331 L,  331 R. The central spoiler portion  3120  has an inverted V-shaped cross-section. A lower edge of the central lever  3100  is straight or upwardly curved with a slight curvature. 
     The central spoiler portion  3120  includes a pair of inclined surfaces  3121 F,  3121 R that are symmetrical in the width direction of the central lever  3100 . The inclined surfaces  3121 F,  3121 R are located in the lateral surfaces of the central spoiler portion  3120 . The inclined surfaces  3121 F,  3121 R extend in the longitudinal direction of the wiper rubber  310  in the central lever  3100  and form the lateral surfaces of the central spoiler portion  3120 . Accordingly, the central spoiler  331 L,  331 R is integrated in the central lever  3100  through the central spoiler portion  3120  having the inclined surfaces  3121 F,  3121 R. An apex portion  3122  interconnects the inclined surfaces  3121 F,  3121 R at their upper edges. 
     The inclined surfaces  3121 F,  3121 R includes a concave surface. A width of the apex portion  3122  becomes sharply narrow from the bracket portion  1110  and then is constant. The inclined surfaces  3121 F,  3121 R are concave in harmony with such width variance of the apex portion  3122 . Thus, the cross-sectional profile of the central spoiler  331 L,  331 R, which the inclined surfaces  3121 F,  3121 R of the central spoiler portion  3120  define, is generally a triangle having both concave legs. The central spoiler portion  3120  has an arm receiving portion  3126  that receives a portion of the intermediate lever  3200 L,  3200 R. The arm receiving portion  3126  is defined by a space between the inclined surfaces  3121 F,  3121 R and an interior space of the joint portion  1125 . 
     Each intermediate lever  3200 L,  3200 R is joined to the central lever  3100  and holds the wiper rubber assembly  310 ,  320 . Descriptions are made as to the intermediate lever  3200 L with reference to  FIGS. 49 to 51 . The intermediate lever  3200 L and the intermediate lever  3200 R are symmetrical in the longitudinal direction of the lever assembly  3000 . The intermediate lever  3200 L,  3200 R includes an intermediate arm  3210  to be situated in the arm receiving portion  3126  of the central lever  3100  and an intermediate spoiler portion  3220  oppositely extending from the intermediate arm  3210 . The intermediate arm  3210  has an inverted U-shaped cross-section. The intermediate spoiler portion  3220  has an inverted V-shaped cross-section. The intermediate spoiler portion  3220  has a stepped surface  3224   a  at a longitudinal inner end portion  3223 . The longitudinal inner end portion  3223  has width and height dimension less than the stepped surface  3224   a . The intermediate arm  3210  extends from the longitudinal inner end portion  3223  toward the central lever  3100 . A lower edge of the intermediate arm  3210  and a lower edge of the intermediate spoiler portion  3220  form an approximately straight line. 
     The intermediate spoiler portion  3220  has a pair of inclined surfaces  3221 F,  3221 R, which are symmetrical in the width direction of the intermediate lever  3200 L,  3200 R and are located in the lateral surfaces of the intermediate spoiler portion  3220 . The inclined surfaces  3221 F,  3221 R extend in the longitudinal direction of the wiper rubber  310  in the intermediate lever  3200 L,  3200 R and form the lateral surfaces of the intermediate spoiler portion  3220 . Accordingly, the intermediate spoiler  332 L,  332 R is integrated in the intermediate lever  3200 L,  3200 R through the intermediate spoiler portion  3220  having the inclined surfaces  3221 F,  3221 R. An apex portion  3222  interconnects the inclined surfaces  3221 F,  3221 R at their upper edges. The inclined surfaces  3221 F,  3221 R are concave in the width direction of the intermediate lever  3200 L  3200 R. The inclined surfaces  3221 F,  3221 R is curved with the same curvature as that of the inclined surfaces  3121 F,  3121 R at the stepped surface  1124  of the central spoiler portion  3120 . Further, a height dimension of the inclined surfaces  3221 F,  3221 R decreases gradually toward a longitudinal outer end of the intermediate lever  3200 L,  3200 R. 
     The central lever  3100  and the intermediate lever  3200 L,  3200 R are joined to each other via a hinge-joint portion  3400 L,  3400 R penetrating through the joint portion  1125  of the central lever and the intermediate arm  3210  of the intermediate lever. When the central lever  3100  and the intermediate lever  3200 L,  3200 R are joined to each other, the intermediate arm  3210  is situated in the arm receiving portion  3126  of the central spoiler portion  3120  and is thus hidden within the central spoiler portion  3120  when viewed from outside. The hinge-joint portion  3400 L,  3400 R has the same configuration as the hinge-joint portion  1400 L,  1400 R of the first embodiment. Through apertures  3212   a  for hinge-joint are formed in a portion of the intermediate arm  3210 , which corresponds to the joint portion  1125  of the central lever  3100 , in a width direction thereof. The hinge insert  1420  is nested on the intermediate arm  3210  such that the through apertures  1421  and the through apertures  3212   a  in alignment with each other. Thereafter, the joint portion  1125  of the central lever  3100  is nested on the hinge insert  1420  such that the through apertures  1126  are aligned with the through apertures  1421 . The rivet  1410  is pierced through the through apertures  1126 ,  1421 ,  3212   a  and then riveted thereto, thus forming the hinge-joint portions  3400 L,  3400 R. 
     The intermediate lever  3200 L,  3200 R includes a joint portion  3227 , which extends from a longitudinal outer end portion  3225  of the intermediate spoiler portion  3220  toward the distal end of the wiper blade  300  and has an inverted U-shaped cross section. The joint portion  3227  has width and height dimensions less than the longitudinal outer end portion  3225  of the intermediate spoiler portion  3220 . The intermediate spoiler portion  3220  has an arm receiving portion  3226  receiving the end arm  2310  of the end lever. The arm receiving portion  3226  is defined by a space between the inclined surfaces  3221 F,  3221 R and an interior space of the joint portion  3227 . The joint portion  3227  participates in hinge-joint to the end lever  2300 L,  2300 R. The joint portion  3227  has a slit  3228  at its top and indentations  3229  at its lower edge. The slit  3228  and the indentations  3229  participate in engagement with the joint cover  1430 ′. 
     In this embodiment, each intermediate lever  3200 L,  3200 R holds the wiper rubber assembly  310 ,  320  at two pressure points. For connection to the wiper rubber assembly  310 ,  320 , each intermediate lever  3200 L,  3200 R has a yoke lever  3230  hinge-jointed to a distal end of the intermediate arm  3210 . Referring to  FIGS. 52 and 53 , the yoke lever  3230  has an inverted U-shaped cross-section and includes yoke arms  3231  extending from a central through aperture  3232  in opposite directions. Clamps  3233  for holding the wiper rubber assembly  310 ,  320  are formed at both ends of the yoke arms  3231  of the yoke lever  3230  respectively. The clamps  3233  have the same shape as the clamp  1311  of the first embodiment. 
     A joint portion  3211  for hinge connection to the yoke lever  3230  is formed at the distal end of the intermediate arm  3210 . Through apertures  3213  are formed in both lateral walls of the joint portion  3211 . A distal end surface  3214  of the intermediate arm  3210  is inclined at an acute angle toward the center of the wiper rubber assembly  310 ,  320 . A hinge insert  3240  shown in  FIGS. 54 and 55  connects the yoke lever  3230  to the intermediate arm  3210 . The hinge insert  3240  has a body  3241  of an inverted U-shaped cross-section such that a portion of the yoke lever  3230  with the through apertures  3232  formed therein is fitted to the body  3241 . Through apertures  3242  are formed in both lateral walls of the body  3241  respectively. A stepped portion  3243  is formed in the vicinity of a longitudinal inner end of the body  3241 . The stepped portion  3243  is formed with a stopper surface  3344  that abuts the distal end surface  3214  of the intermediate arm  3210  to thus restrict rotation of the hinge insert  3340  or the yoke lever  3230 . The intermediate arm  3210  and the yoke lever  3230  are hinge-jointed to each other in the following manner: the hinge insert  3240  is nested on a midway portion of the yoke lever  3230 ; the hinge insert  3240  is inserted to the joint portion  3211  formed at the distal end of the intermediate arm  3210 ; and a rivet or pin is fitted to the through apertures  3232  of the yoke lever  3230 , the through apertures  3242  of the hinge insert  3240  and the through apertures  3213  of the intermediate arm  3210  and is then riveted thereto. 
     Each end lever  2300 L,  2300 R is hinge-jointed to the intermediate lever  3200 L,  3200 R and holds the wiper rubber assembly  310 ,  320 . When the intermediate lever  3200 L,  3200 R and the end lever  2300 L,  2300 R are hinge-joined to each other, the end arm  2310  is situated in the arm receiving portion  3226  of the intermediate spoiler portion  3220  and is thus hidden within the intermediate spoiler portion  3220  when viewed from outside. The intermediate lever  3200 L,  3200 R and the end lever  2300 L,  2300 R are joined to each other through a hinge-joint portion  3400 ′L,  3400 ′R penetrating through both the joint portion  3227  and the end arm  2310 . Through apertures  3212   b  for hinge-joint are formed in the joint portion  3227  of the intermediate lever  3200 L,  3200 R in a width direction. The hinge insert  1420  is nested on the end arm  2310  of the end lever such that the through apertures  1421  and the through apertures  2312  are aligned with each other. Thereafter, the joint portion  3227  of the intermediate lever  3200 L,  3200 R is nested on the hinge insert  1420  such that the through apertures  3212   b  are aligned with the through apertures  1421 . The rivet  1410  is pierced through the through apertures  3212   b ,  1421 ,  2312  and is riveted thereto, thereby forming the hinge-joint portion  3400 ′L,  3400 ′R. 
     Referring to  FIG. 56 , the lever assembly  3000  includes the joint cover  1430 , which is disposed between the central lever  3100  and the intermediate lever  3200 L,  3200 R to cover the hinge-joint portion  3400 L,  3400 R, and the joint cover  1430 ′, which is disposed between the intermediate lever  3200 L,  3200 R and the end lever  2300 L,  2300 R to cover the hinge-joint portion  3400 ′L,  3400 ′R. The joint cover  1430  snap-engages the joint portion  1125  of the central lever. The joint cover  1430 ′ snap-engages the joint portion  3227  of the intermediate lever. 
     The wiper rubber assembly  310 ,  320  and the lever assembly  3000  are coupled to each other by fitting the clamps  3233  of the yoke lever  3230  and the clamps  2311 ,  2325  of the end levers  2300 L,  2300 R to the second groove  114  of the wiper rubber  310 . If the both ends of the clamp  2325  of the end lever  2300 L are inserted to the insertion holes  117  and the sandwiching portion  1332  of the clamp insert  1330  is placed in the recesses  116 , then the wiper rubber assembly  310 ,  320  are fixed to the lever assembly  3000 . 
     In the assembled wiper blade  300 , when no load acts on the wiper blade  300 , the central spoiler portion  3120 , the joint cover  1430 , the intermediate spoiler portion  3220 , the joint cover  1430 ′ and the end spoiler portion  2320  can become open with a slight gap therebetween. With the inclined stepped surfaces  1124 ,  3224   a ,  3224   b ,  2324  and the shapes of the joint covers  1430 ,  1430 ′ corresponding thereto, the intermediate lever  3200 L,  3200 R and the end lever  2300 L,  2300 R cannot pivot upwardly relative to the central lever  3100 . Accordingly, when the wiper arm applies a force to the wiper blade  200  toward the windshield, the central spoiler portion  3120 , the joint cover  1430 , the intermediate spoiler portion  3220 , the joint cover  1430 ′ and the end spoiler portion  2320  are brought into close abutment with one another in the longitudinal direction, thereby bringing the wiper rubber  310  into strong contact with the windshield. 
     Referring again to  FIGS. 44 to 46  showing the assembled wiper blade  300 , the lever assembly  3000  holds the wiper rubber assembly  310 ,  320  at eight pressure points via the clamps  2325 ,  2311  of the end levers  2300 L,  2300 R and the clamps  3233  of the yoke levers  3230 . Further, the central lever  3100 , the intermediate levers  3200 L,  3200 R and the end levers  2300 L,  2300 R are straight arranged along the length of the wiper rubber  310  and are at the approximately same height on the wiper rubber  310 . Further, in the assembled wiper blade  300 , the inclined surfaces  3121 F,  3121 R of the central spoiler portion  3120 , the inclined surfaces  1431   f ,  1431 R of the joint cover  1430 , the inclined surfaces  3221 F,  3221 R of the intermediate spoiler portion  3220 , the inclined surfaces  1431 F,  1431 R of the joint cover  1430 ′ and the inclined surfaces  2321 F,  2321 R of the end spoiler portion  2320  are straight adjoined one after another, thereby defining the spoiler  330 L,  330 R having the cross-sectional profile with its height dimension decreasing gradually toward the distal end of the wiper blade  300 . 
     In another embodiment similar to this embodiment, the wiper rubber assembly  310 ,  320  can be held at eight pressure points without the yoke lever  3230 . In such an example, the lever assembly may be constructed such that two intermediate levers each having the clamp at its distal end of the intermediate arm (e.g., the intermediate lever  2200 L,  2200 R in the second embodiment) are juxtaposed. That is, the lever assembly of such an example may be configured such that the central lever, the first and second intermediate levers (e.g., intermediate levers similar to the intermediate lever  2200 L,  2200 R) and the end levers may be straight arranged and hinge-jointed one another. 
       FIGS. 57 to 60  show a wiper blade  400  according to a fourth embodiment and elements or components constituting the wiper blade  400 . In a lever assembly  4000  of the wiper blade  400  according to this embodiment, opposing end surfaces of adjacent levers directly face to each other with little gap therebetween. To this end, the lever assembly  4000  includes a hinge-joint portion of a joint, which is hinge-jointed to the arm of one of the adjacent levers, and which is hidden in and coupled to the spoiler portion of the other of the adjacent levers. Via said joint, the arm of the one of the adjacent levers and the spoiler portion of the other of the adjacent levers, which is further inward than said one of the levers, are hinge-jointed to each other. Accordingly, the wiper blade  400  according to this embodiment does not include the joint cover  1430 ,  1430 ′ in the foregoing embodiments. In  FIGS. 57 to 60 , the same elements or components as those of the wiper blade  200  of the second embodiment are denoted by the same reference numerals. 
     Referring to  FIGS. 57 and 58 , the lever assembly  4000  of the wiper blade  400  holds the wiper rubber assembly  210 ,  220 . The spoiler  430 L,  430 R is integrated in an upper surface of the lever assembly  4000  (an upper or lateral surface of each lever constituting the lever assembly) along a longitudinal direction of the wiper rubber  210 . Each spoiler  430 L,  430 R produces a reaction force preventing the lift of the wiper blade  400 . Similar to the second embodiment, a cross-sectional profile of the spoiler  430 L,  430 R for producing the reaction force includes a triangle having concave legs. The cross-sectional profile of the spoiler  430 L,  430 R decreases in a height dimension toward a distal end of the wiper blade  400 . The lever assembly  4000  includes a central lever  4100  centrally located in the wiper rubber assembly  210 ,  220 , a pair of intermediate levers  4200 L,  4200 R hinge-jointed to both longitudinal ends of the central lever  4100  respectively and a pair of the end levers  2300 L,  2300 R hinge-joined to both longitudinal ends of the intermediate levers  4200 L,  4200 R respectively. Each spoiler  430 L,  430 R comprises a central spoiler  431 L,  431 R, which is integrated in the central lever  4100  to become a section of the spoiler  430 L,  430 R, an intermediate spoiler  432 L,  432 R, which is integrated in the intermediate lever  4200 L,  4200 R to become another section of the spoiler  430 L,  430 R, and an end spoiler  233 L,  233 R, which is integrated in the end lever  2300 L,  2300 R to become yet another section of the spoiler  430 L,  430 R. Each lever has a spoiler portion forming the spoiler section. 
     Referring to  FIGS. 58 and 59 , the central lever  4100  includes a pair of central spoiler portions  4120 , which extend from the bracket portion  1110  in opposite directions in the longitudinal direction of the wiper rubber  210  and define the central spoiler  431 L,  431 R respectively. 
     The central spoiler portion  4120  has a pair of inclined surfaces  4121 F,  4121 R that are symmetrical in the width direction of the central lever  4100 . The inclined surfaces  4121 F,  4121 R are located in the lateral surfaces of the central spoiler portion  4120 . The inclined surfaces  4121 F,  4121 R extend in the longitudinal direction of the wiper rubber  210  in the central lever  4100  and form the lateral surfaces of the central spoiler portion  4120 . Accordingly, the central spoiler  431 L,  431 R is integrated in the central lever  4100  through the central spoiler portion  4120  having the inclined surfaces  4121 F,  4121 R. A longitudinal outer end surface  4123  of the central spoiler portion  4120  is inclined at an acute angle toward the distal end of the wiper rubber  210 . The intermediate lever  4200 L,  4200 R includes the intermediate arm  2210  to be situated inside the central spoiler portion  4120  and an intermediate spoiler portion  4220  oppositely extending from the intermediate arm  2210 . A lower edge of the intermediate arm  2210  and a lower edge of the central spoiler portion  4220  form an approximately straight line. The intermediate spoiler portion  4220  has a pair of inclined surfaces  4221 F,  4221 R, which are symmetrical in the width direction of the intermediate lever  4200 L,  4200 R. The inclined surfaces  4221 F,  4221 R extend in the longitudinal direction of the wiper rubber  210  in the intermediate lever  4200 L,  4200 R and form the lateral surfaces of the intermediate spoiler portion  4220 . Accordingly, the intermediate spoiler  432 L,  432 R is integrated in the intermediate lever  4200 L,  4200 R through the intermediate spoiler portion  4220 . 
     When the central lever  4100  and the intermediate lever  4200 L,  4200 R are joined to each other, the intermediate arm  2210  is situated inside the central spoiler portion  4120  and is thus hidden within the central spoiler portion  4120  when viewed from outside. The intermediate arm  2210  is hinge-jointed to the central spoiler portion  4120  via the joint  4400 . 
     The joint  4400  has a generally triangular cross-section so as to fit inside the central spoiler portion  4120 . Height and width dimensions of the joint  4400  are determined such that a longitudinal outer end portion  4410  of the joint is nested on a portion (e.g., the intermediate arm  2210 ) of one of the adjacent levers (e.g., the intermediate lever  4200 L,  4200 R) and a longitudinal inner end portion  4420  of the joint is fitted to the spoiler portion of the other of the adjacent levers (e.g., the central lever  4100 ), which is further inward than said one of the adjacent levers. The joint  4400  and the intermediate lever  4200 L,  4200 R are joined to each other by means of hinge-joint between inner surfaces of the joint  4400  and through apertures  2212   a  formed in the intermediate arm  2210 . When hinge-jointed, the longitudinal end portion  4410  of the joint  4400  is nested on the longitudinal inner end portion  2223  of the intermediate spoiler portion  4220 . 
     The joint  4400  has an element snap-engaging the spoiler portion of the other of the adjacent levers (e.g., the central lever  4100 ). Specifically, the joint  4400  has snap protrusions  4430  at its longitudinal inner lower edge. A longitudinal outer end surface of the snap protrusion  4430  is inclined toward the distal end of the wiper rubber  210 . Further, the joint  4400  has an element to be fitted to the end surface of the spoiler portion of the other of the adjacent levers (e.g., the central lever  4100 ). Specifically, the joint  4400  has two mating protrusions  4440  at either longitudinal outer end surface. The spoiler portion of the other of the adjacent levers (e.g. the central spoiler portion  4120  of the central lever  4100 ) has an element for snap-engagement with the joint  4400 . A snap notch  4124 , to which the snap protrusion  4430  is fitted, is formed at a lower edge of the central spoiler portion  4120 . Further, the spoiler portion of the other of the adjacent levers (e.g. the central spoiler portion  4120  of the central lever  4100 ) has an element for engagement with the joint  4400 . Mating notches  4125  mating the mating protrusions  4440  are formed in an outer end surface  4123  of the central spoiler portion  4120 . 
     Referring to  FIGS. 59 and 60 , the intermediate arm  2210  with the joint  4400  hinge-jointed thereto is inserted to the inside of the central spoiler portion  4120  and the joint  4400  attached to the intermediate lever  4200 L,  4200 R is pushed into the central spoiler portion  4120 . Then, the inner surface of the central spoiler portion  4120  is moved along or slid on the outer surface of the joint  4400  and then the outer end surface  4123  of the central spoiler portion  4120  abuts the longitudinal inner stepped surface  2224   a  of the intermediate spoiler portion  4220  or faces the same with little gap therebetween. Further, the mating protrusions  4440  of the joint  4400  are fitted to the mating notches  4125  of the central spoiler portion  4120  and the snap protrusion  4430  of the joint  4400  snap-engages the snap notch  4124  of the central spoiler portion  4120 , thereby coupling the joint  4400  to the central lever  4100 . 
     The intermediate lever  4200 L,  4200 R and the end lever  2300 L,  2300 R are also joined to each other by means of the above-described joint. In this case, the joint between the intermediate lever  4200 L,  4200 R and the end lever  2300 L,  2300 R has width and height dimensions less than those of the above-described joint  4400 . Further, a longitudinal outer end surface of the intermediate spoiler portion  4220  of the intermediate lever  4200 L,  4200 R is inclined toward the distal end of the wiper rubber  210 . Mating notches are formed in the longitudinal outer end surface of the intermediate spoiler portion  4220  and a snap notch is formed at the lower edge of the intermediate spoiler portion  4220 . The joint between the intermediate lever  4200 L,  4200 R and the end lever  2300 L,  2300 R is joined to the end arm  2310  of the end lever  2300 L,  2300 R by means of hinge-joint and has mating protrusions and snap protrusions corresponding to the mating notches and the snap notches respectively. 
     The above-described joint and the connection configuration using the same may be employed to a lever assembly configured to hold the wiper rubber at four pressure points (e.g., the lever assembly  1000  of the first embodiment) or a lever assembly configured to hold the wiper rubber at eight pressure points (e.g., the lever assembly  3000  of the third embodiment). 
       FIGS. 61 to 72  show a wiper blade according to a fifth embodiment, generally denoted by  500 , and elements or components constituting the wiper blade  500 . In a lever assembly  5000  of the wiper blade  500  according to this embodiment, opposing end surfaces of adjacent levers face to each other with little gap therebetween. Further, in this embodiment, a hinge-joint portion between adjacent levers of the lever assembly  5000  directly hinge-joints an arm, which is provided in one of the adjacent levers of the lever assembly  5000  to hold the wiper rubber, to an inside of a spoiler portion of the other of the adjacent levers. Such a hinge-joint configuration may be employed to any one of the wiper blades  100 ,  200 ,  300  of the foregoing embodiment. In  FIGS. 61 to 72 , the same elements or components as those of the wiper blade  200  of the second embodiment are denoted by the same reference numerals. 
     Referring to  FIGS. 61 to 63 , the wiper blade  500  according to the fifth embodiment has a lever assembly  5000  holding and supporting the wiper rubber assembly  210 ,  220 . Further, the wiper blade  500  includes a pair of spoilers  530 L,  530 R. The left spoiler  530 L and the right spoiler  530 R are symmetrical relative to a longitudinal center of the wiper rubber  210 . The spoilers  530 L,  530 R are integrated in the lever assembly  5000  and extend in the longitudinal direction of the wiper rubber  210 . 
     The lever assembly  5000  connects the wiper rubber assembly  210 ,  220  to the wiper arm and supports the wiper rubber assembly  210 ,  220  with respect to the wiper arm. In this embodiment, the lever assembly  5000  includes a central lever  5100  centrally located in the wiper rubber assembly  210 ,  220 , a pair of intermediate levers  5200 L,  5200 R joined to the central lever  5100  respectively and a pair of end levers  5300 L,  5300 R joined to the intermediate levers  5200 L,  5200 R respectively. The central lever, the intermediate lever and the end lever have an appearance similar to the central lever, the intermediate lever and the end lever of the foregoing embodiments respectively. The levers are straight arranged along the length of the wiper rubber  210  to thus constitute the lever assembly  5000 . Adjacent levers are hinge-jointed to each other. The levers  5100 ,  5200 L,  5200 R,  5300 L,  5300 R have an elongated hollow shape and may be made by injection molding a plastic material. 
     The pair of the spoilers  530 L,  530 R are integrated in an upper surface of the lever assembly  5000  along the longitudinal direction of the wiper rubber  210 . A portion of the upper surface of the lever assembly  5000  (a portion of an upper or lateral surface of each lever constituting the lever assembly) defines the spoiler  530 L,  530 R. 
     Each spoiler  530 L,  530 R reacts to wind or air stream impinging against the wiper blade  500  during running of a motor vehicle and produces a reaction force preventing the wiper blade  500  from being lifted. Such a reaction force is produced by interaction between wind or air stream and a cross-sectional profile of the spoiler  530 L,  530 R. The cross-sectional profile of the spoiler  530 L,  530 R may be constant along the length of the lever assembly  5000  or vary in width and height dimensions toward a distal end of the wiper blade  500 . Further, the cross-sectional profile may be symmetrical or asymmetrical in a width direction of the wiper rubber assembly (in a direction perpendicular to the longitudinal direction of the wiper rubber). In this embodiment, similar to the foregoing embodiments, the cross-sectional profile of the spoiler  530 L,  530 R includes a triangle having somewhat concave legs. 
     Each spoiler  530 L,  530 R comprises spoiler sections located in the respective levers  5100 ,  5200 L,  5200 R,  5300 L,  5300 R of the lever assembly  5000 . The spoiler sections of the respective levers are straight adjoined one after another, i.e. the spoiler sections of the respective levers are straight adjoined one after another with the spoiler sections of adjacent levers adjoining each other, thereby defining the spoiler  530 L,  530 R. A portion of the upper surface of the lever, specifically a portion or the entirety of the lateral surface of the spoiler portion forms the spoiler section. Further, a spoiler portion included in each lever forms each spoiler section. In the below descriptions of the wiper blade  500  according to the fifth embodiment, regarding the spoiler  530 L,  530 R formed in the lever assembly  1000 , a spoiler section integrated in the central lever  5100  to become a section of the spoiler  530 L,  530 R is referred to as a central spoiler  531 L,  531 R, and a spoiler section integrated in the intermediate lever  5200 L,  5200 R to become another section of the spoiler  530 L,  530 R is referred to as an intermediate spoiler  532 L,  532 R, and a spoiler section integrated in the end lever  5300 L,  5300 R to become yet another section of the spoiler  530 L,  530 R is referred to as an end spoiler  533 L,  533 R. 
     The central lever  5100  centrally located in the lever rubber assembly  210 ,  220  is releasably coupled to the distal end of the wiper arm. Referring to  FIGS. 64 to 67 , the central lever  5100  includes a bracket portion  5110  at its middle. The bracket portion  5110  has a shape of a vertically-pierced rectangular parallelepiped. A pin is formed in the middle of the bracket portion  5110  in a direction perpendicular to the longitudinal direction of the central lever  5100 . The pin  5111  participates in connection to the wiper arm. An adaptor (not shown), which is configured to be connected to a corresponding element provided in the distal end of the wiper arm through fitting, snapping, engaging, etc., may be coupled to the pin  5111 . The pin  5111  may function as a pivot shaft of the wiper blade  500 . 
     Further, the central lever  5100  includes a pair of central spoiler portions  5120 , which extend in opposite directions from the bracket portion  5110  in the longitudinal direction of the wiper rubber  210  and form the central spoiler  531 L,  531 R. The central spoiler portion  5120  has an inverted V-shaped cross-section. A lower edge of the central lever  5100  (lower edges of the bracket portion  5110  and the central spoiler portion  5120 ) is straight or curved with a slight curvature. The central spoiler portion  5120  includes a pair of inclined surfaces  5121 F,  5121 R that are symmetrical in a width direction of the central lever  5100 . The inclined surfaces  5121 F,  5121 R are located in the lateral surfaces of the central spoiler portion  5120 . The inclined surfaces  5121 F,  5121 R extend in the longitudinal direction of the wiper rubber  510  in the central lever  5100  and form the lateral surfaces of the central spoiler portion  5120 . Accordingly, the central spoiler  531 L,  531 R is integrated in the central lever  5100  through the central spoiler portion  5120  having the inclined surfaces  5121 F,  5121 R. An apex portion  5122  interconnects the inclined surfaces  5121 F,  5121 R at their upper edges. 
     The inclined surfaces  5121 F,  5121 R includes a concave surface. A width of the apex portion  5122  becomes sharply narrow from the bracket portion  5110  and is then constant. The inclined surfaces  5121 F,  5121 R are concave in harmony with such a width of the apex portion  5122 . Thus, the cross-sectional profile of the central spoiler  531 L,  531 R is generally a triangle having both concave legs. The central spoiler portion  5120  has an arm receiving portion  5126  that receives a portion of the intermediate lever  5200 L,  5200 R and hides the same therein. The arm receiving portion  5126  is defined by a space between the inclined surfaces  5121 F,  5121 R. A longitudinal outer end surface  5123  of the central spoiler portion  5120  is inclined at an acute angle toward the distal end of the wiper rubber  210 . The central lever  5100  has a plurality of transverse ribs  5127 , which are oriented in the width direction, and a longitudinal rib  5128 , which is oriented in the longitudinal direction and intersects the transverse ribs  5127 . The transverse ribs  5127  and the longitudinal rib  5128  protrude such that they do not interfere with a top side of a portion of the intermediate lever  5200 L,  5200 R to be situated in the central spoiler portion  5120 . 
     Each intermediate lever  5200 L,  5200 R is joined to the central lever  5100  and holds the wiper rubber assembly  210 ,  220 . Descriptions are made as to the intermediate lever  5200 L with reference to  FIGS. 64, 65, 68 and 69 . The intermediate lever  5200 L and the intermediate lever  5200 R are symmetrical in the longitudinal direction of the lever assembly  5000 . The intermediate lever  5200 L,  5200 R includes an intermediate arm  5210  to be situated in the arm receiving portion  5126  of the central spoiler portion  5120  and an intermediate spoiler portion  5220  oppositely extending from the intermediate arm  5210 . The intermediate arm  5210  has an inverted U-shaped cross-section. The intermediate spoiler portion  5220  has an inverted V-shaped cross-section. The intermediate arm  5210  extends from a longitudinal inner end surface  5223  of the intermediate spoiler portion  5220  toward the central lever  5100 . A lower edge of the intermediate arm  5210  and a lower edge of the intermediate spoiler portion  5220  form an approximately straight line. 
     Each intermediate lever  5200 L,  5200 R has a clamp  5211  for fixing the wiper rubber assembly  210 ,  220 . The clamp  5211  is formed at a distal end of the intermediate arm  5210 . The clamp  5211  has a generally rectangular cross-section with its bottom side cut away partially and thus both ends thereof extend inwardly. When the intermediate lever  5200 L,  5200 R and the wiper rubber assembly  210 ,  220  are coupled to each other, an upper inner surface of the clamp  5211  is placed on a top side of the wiper rubber  210  and lateral portions of the clamp  5211  sandwich the spring rail  220  and a portion of the wiper rubber  210  adjacent thereto and the both ends of the clamp  5211  are inserted to the second groove  114  of the wiper rubber (see  FIG. 72 ). 
     The intermediate spoiler  532 L,  532 R is integrally formed in the intermediate lever  5200 L,  5200 R. The intermediate spoiler portion  5220  has a pair of inclined surfaces  5221 F,  5221 R that are symmetrical in the width direction of the intermediate lever  5200 L,  5200 R. The inclined surfaces  5221 F,  5221 R are located in the lateral surfaces of the intermediate spoiler portion  5220 . The inclined surfaces  5221 F,  5221 R extend in the longitudinal direction of the wiper rubber  210  in the intermediate lever  2200 L,  2200 R and form the lateral surfaces of the intermediate spoiler portion  5220 . Accordingly, the intermediate spoiler  532 L,  532 R is integrated in the intermediate lever  5200 L,  5200 R through the intermediate spoiler portion  5220  having the inclined surfaces  5221 F,  5221 R. An apex portion  5222  interconnects the inclined surfaces  5221 F,  5221 R at their upper edges. The inclined surfaces  5221 F,  5221 R includes a concave surface. Further, a height dimension of the inclined surfaces  5221 F,  5221 R decreases gradually toward a longitudinal outer end of the intermediate lever  5200 L,  5200 R The inclined surfaces  5221 F,  5221 R may be curved with the same curvature as that of the inclined surfaces  5121 F,  5121 R of the central spoiler portion  5120 , or curved with a curvature varying therefrom. In this embodiment, the inclined surfaces  5221 F,  5221 R of the intermediate spoiler portion  5220  is curved with the same curvature as that of the inclined surfaces  5121 F,  5121 R at the outer end surface  5123  of the central spoiler portion  5120 . 
     The intermediate spoiler portion  5220  has an arm receiving portion  5226 , which receives a portion of the end lever  5300 L,  5300 R and hides the same therein. The arm receiving portion  5226  is defined by a space between the inclined surfaces  5221 F,  5221 R. The intermediate lever  5200 L,  5200 R has a plurality of transverse ribs  5227  and a longitudinal rib  5228  therein. The transverse ribs  5227  are oriented in the width direction. The longitudinal rib  5228  is oriented in the longitudinal direction and intersects the transverse ribs  5227 . The transverse ribs  5227  and the longitudinal rib  5228  are located in the intermediate arm  5210  as well as the intermediate spoiler portion  5220 . Further, the transverse ribs  5227  and the longitudinal rib  5228  in the intermediate spoiler portion  5220  protrude such that they do not interfere with a portion of the end lever  5300 L,  5300 R to be situated in the intermediate spoiler portion  5220 . 
     The central lever  5100  and the intermediate lever  5200 L,  5200 R are joined to each other via a hinge-joint portion hinge-jointing the interior of the central spoiler portion  5120  and the intermediate arm  5210 . When the central lever  5100  and the intermediate lever  5200 L,  5200 R are joined to each other, the intermediate arm  5210  of the intermediate lever is situated in the arm receiving portion  5126  of the central spoiler portion  5120  and is thus hidden within the central spoiler portion  5120  when viewed from outside. In other words, a portion (e.g., the intermediate arm  5210 ) of one of the adjacent levers (e.g., the intermediate lever  5200 L,  5200 R) is situated in and hinge-jointed to the spoiler portion of the other of the adjacent levers (e.g., the central lever  5100 ), which is further inward than said one of the adjacent levers. 
     The hinge-joint portion of this embodiment comprises a pair of hinge pins  5411  and a pair of fitting holes  5421  to which the hinge pins  5411  are fitted respectively. Hinge engagement between the hinge pins  5411  and the fitting holes  5421  makes the hinge-joint portion. In this embodiment, the hinge pins  5411  are disposed in the arm receiving portion  5126  of the central spoiler portion  5120 , while the fitting holes  5421  are disposed in the intermediate arm  5210  of the intermediate lever  5200 L,  5200 R. 
     The central lever  5100  has an element for restricting the intermediate arm  5210  from moving in the width direction of the central lever  5100  so that the intermediate lever  5200 L,  5200 R joined to the central lever can be retained relative to the central lever  5100  without shake. Said element is configured such that the intermediate arm  5210  is inserted to the element and the movement in its width direction is restricted. The element comprises a pair of opposing surface portions or protrusion portions, which are located in the arm receiving portion  5126  of the central spoiler portion  5120 , and to which the intermediate arm  5210  can be inserted or fitted. In this embodiment, the element comprises two pairs of raised surfaces  5131 ,  5132  formed in a lower inner surface of the central spoiler portion  5120 . The raised surfaces  5131 ,  5132  of each pair are opposed to each other inside the central spoiler portion  5120  and protrude inwardly of the central spoiler portion  5120 . The hinge pins  5411  protrude from the raised surfaces  5131  inwardly of the central spoiler portion  5120 . The hinge pin  5411  has a beveled surface  5411   a  at its lower portion to facilitate fitting to the fitting holes  5421 . When the central lever  5100  and the intermediate lever  5200 L,  5200 R are joined to each other, the intermediate arm  5210  is inserted or fitted in between the raised surfaces  5131 ,  5132 . Spacing between the raised surfaces  5131 ,  5132  of each pair is almost equal to or somewhat greater than the width of the intermediate arm  5210 . 
     The fitting holes  5421  may pierce through the lateral portions of the intermediate arm  5210  or be formed at a predetermined depth. The fitting holes  5421  are spaced from the longitudinal inner end surface  5223  of the intermediate spoiler portion  5220  by the spacing between the longitudinal outer end surface  5123  of the central spoiler portion  5120  and the hinge pin  5411 . 
     The end levers  5300 L,  5300 R are joined to the intermediate levers  5200 L,  5200 R respectively and hold the wiper rubber assembly  210 ,  220 . Descriptions are made as to the end lever  5300 L with reference to  FIGS. 64, 65, 70 and 71 . The end lever  5300 L and the end lever  5300 R are symmetrical in the longitudinal direction of the lever assembly  5000 . The end lever  5300 L,  5300 R includes an end arm  5310  to be situated in the arm receiving portion  5226  of the intermediate spoiler portion  5220  and an end spoiler portion  5320  oppositely extending from the end arm  5310 . The end arm  5310  has an inverted U-shaped cross-section. The end spoiler portion  5320  has an inverted V-shaped cross-section. The end arm  5310  extends from a longitudinal inner end surface  5323  of the end spoiler portion  5320  toward the central lever  5100 . A lower edge of the end arm  5310  and a lower edge of the end spoiler portion  5320  form an approximately straight line. 
     The end spoiler  533 L,  533 R is integrally formed in the end lever  5300 L,  5300 R. The end spoiler portion  5320  has a pair of inclined surfaces  5321 F,  5321 R that are symmetrical in the width direction of the end lever  5300 L,  5300 R. The inclined surfaces  5321 F,  5321 R are located in the lateral surfaces of the end spoiler portion  5320 . The inclined surfaces  5321 F,  5321 R extend in the longitudinal direction of the wiper rubber  210  in the end lever  5300 L,  5300 R and form the lateral surfaces of the end spoiler portion  5320 . Accordingly, the end spoiler  533 L,  533 R is integrated in the end lever  5300 L,  5300 R through the end spoiler portion  5320  having the inclined surfaces  5321 F,  5321 R. An apex portion  5322  interconnects the inclined surfaces  5321 F,  5321 R at their upper edges. The inclined surfaces  5321 F,  5321 R includes a concave surface. Further, a height dimension of the inclined surfaces  5321 F,  5231 R decreases gradually toward the distal end of the wiper blade  500 . Further, lower edges of the inclined surfaces  5321 F,  5321 R approach each other at a distal end of the end lever  5300 L,  5300 R, thereby forming a round distal end of the end lever  5300 L,  5300 R along with the apex portion  5322 . The inclined surfaces  5321 F,  5321 R may be curved with the same curvature as that of the inclined surfaces  5221 F,  5221 R of the intermediate spoiler portion  5220 , or curved with a curvature varying therefrom. In this embodiment, the inclined surfaces  5321 F,  5321 R of the end spoiler portion is curved with the curvature greater than that of the inclined surfaces  5221 F,  5221 R at the outer end surface  5224  of the intermediate spoiler portion  5220 . 
     The end lever  5300 L,  5300 R has a plurality of transverse ribs  5327  and a longitudinal rib  5328  therein. The transverse ribs  5327  are oriented in the width direction. The longitudinal rib  5328  is oriented in the longitudinal direction and intersects the transverse ribs  5327 . The transverse ribs  5327  and the longitudinal rib  5328  are located in the end arm  5310  as well as the end spoiler portion  5320 . 
     Each end lever  5300 L,  5300 R has two clamps  5325 ,  5311  for fixing the wiper rubber assembly  210 ,  220 . A longitudinal inner clamp  5311  is formed at a distal end of the end arm  5310 . The clamp  5311  has the same configuration as the clamp  5211  of the intermediate lever. A longitudinal outer clamp  5325  is formed at a lower edge of the end spoiler portion  5320  in the vicinity of a longitudinal outer end thereof. The clamp  5325  extends from the lower edge of the end spoiler portion  5320  in a V shape. Both ends of each clamp  5311 ,  5325  are inserted to the second groove  114  of the wiper rubber  210 . A pair of longitudinally extending ribs  5329  are formed inside the end spoiler portion  5320  opposite the clamp  5325 . A portion of the rib  5329  above the both ends of the clamp  5325  protrude downwardly to form a pressing portion  5333 . When the lever assembly  5000  and the wiper rubber assembly  210 ,  220  are coupled to each other, the pressing portion  5333  presses the top side of the wiper rubber  210  downwardly (toward the both ends of the clamp  5325 ) or is placed on the top side of the wiper rubber  210  with little gap. Thus, the wiper rubber  210  is firmly fixed to the clamp  5325  by the pressing portion  5333 . 
     The intermediate lever  5200 L,  5200 R and the end lever  5300 L,  5300 R are joined to each other via a hinge-joint portion hinge-jointing the interior of the intermediate spoiler portion  5220  and the end arm  5310  to each other. When the intermediate lever  5200 L,  5200 R and the end lever  5300 L,  5300 R are joined to each other, the end arm  5310  is situated in the arm receiving portion  5226  of the intermediate spoiler portion  5220  and is thus hidden within the intermediate spoiler portion  5220  when viewed from outside. 
     The hinge-joint portion between the intermediate lever  5200 L,  5200 R and the end lever  5300 L,  5300 R comprises a pair of hinge pins  5412  and a pair of fitting holes  5422  to which the hinge pins  5412  are fitted respectively. The hinge pins  5412  are disposed in the arm receiving portion  5226  of the intermediate spoiler portion  5220 . The fitting holes are disposed in the end arm  5310 . 
     The intermediate lever  5200 L,  5200 R has an element for restricting the end arm  5310  from moving in the width direction of the intermediate lever  5200 L,  5200 R so that the end lever  5300 L,  5300 R joined to the intermediate lever can be retained relative to the intermediate lever  5200 L,  5200 R without shake. Said element in the intermediate lever  5200 L,  5200 R has the same configuration as the element described above in connection with the central lever  5100 . As said element, two pairs of raised surfaces  5231 ,  5232  are formed in a lower inner surface of the intermediate lever  5200 L,  5200 R. The raised surfaces  5231 ,  5232  of each pair are opposed to each other inside the intermediate spoiler portion  5220  and protrude inwardly of the arm receiving portion  5226 . The hinge pins  5412  protrude from the raised surfaces  5231  inwardly of the arm receiving portion  5226 . The hinge pin  5412  has a beveled surface  5412   a  at its lower portion to facilitate fitting to the fitting holes  5422 . When the intermediate lever  5200 L,  5200 R and the end lever  5300 L,  5300 R are joined to each other, the end arm  5310  is inserted or fitted in between the raised surfaces  5231 ,  5232 . Spacing between the raised surfaces  5231 ,  5232  of each pair is almost equal to or somewhat greater than the width of the end arm  5310 . 
     The fitting holes  5422  may pierce through the lateral portions of the end arm  5310  or be formed at a predetermined depth. The fitting holes  5422  are spaced from the longitudinal inner end surface  5323  of the end spoiler portion  5320  by the spacing between the longitudinal outer end surface  5224  of the intermediate spoiler portion  5220  and the hinge pin  5412 . A guide groove  5423  for guiding the insertion of the hinge pin  5412  is formed from a top side of the end arm  5310  to the fitting hole  5422 . 
     Descriptions are made as to an example assembly of the wiper blade  500  according to the fifth embodiment with reference to  FIG. 72 . 
     The longitudinal outer end surface  5123  of the central spoiler portion  5120  and the longitudinal inner end surface  5223  of the central spoiler portion  5220  are approximated and one of them is pressed or pushed down against the other of them. Then, the hinge pins  5411  of the central spoiler portion  5120  enter the fitting holes  5421  while pressing or pinching an upper portion of the intermediate arm  5210 . Subsequently, the hinge pins  5411  snap-engage the fitting holes  5421 , thereby hinge-jointing the central lever  5100  and the intermediate lever  5200 L to each other via the hinge pins  5411  and the fitting holes  5421 . When the central lever  5100  and the intermediate lever  5200 L are joined to each other, a portion of the intermediate arm  5210  adjacent to the fitting hole  5421  and another portion further inward than the portion are sandwiched between the raised surfaces  5131  as well as between the raised surfaces  5132 . The intermediate lever  5200 L and the end lever  5300 L are joined to each other in the above-described manner. That is, the longitudinal outer end surface  5224  of the intermediate spoiler portion  5220  and the longitudinal inner end surface  5323  of the end lever  5300 L are approximated and one of them is pressed against the other of them. Then, the hinge pins  5412  of the intermediate spoiler portion  5220  snap-engage the fitting holes  5422  of the end arm  5210 , thereby hinge-jointing the intermediate lever  5200 L and the end lever  5300 L to each other. Hinge-joint between the central lever  5100  and the intermediate lever  5200 R and hinge-joint between the intermediate lever  5200 R and the end lever  5300 L are made in the above-described manner. 
     By fitting the clamps  5325 ,  5311  of the end levers  5300 L,  5300 R and the clamps  5211  of the intermediate levers  5200 L,  5200 R to the second groove  114  of the wiper rubber  210 , the wiper rubber assembly  210 ,  220  and the lever assembly  5000  are coupled to each other. For example, the clamps  5325 ,  5311  of the end lever  5300 L, the clamp  5211  of the intermediate lever  5200 L, the clamp  5211  of the intermediate lever  5200 R and the clamps  5311 ,  5325  of the end lever  5300 R are inserted to the second groove  114  of the wiper rubber one after another while sliding the wiper rubber assembly  210 ,  220  along the lever assembly  5000 . If the both ends of the clamp  5325  of the end lever  5300 L is fitted to the insertion holes  117 , then the wiper rubber assembly  210 ,  220  is fixed to the lever assembly  5000 . 
     Referring again to  FIGS. 61 to 63  showing the assembled wiper blade  500 , the lever assembly  5000  holds the wiper rubber assembly  210 ,  220  at six pressure points via the clamps  5325 ,  5311  of the end levers  5300 L,  5300 R and the clamps  5211  of the intermediate levers  5200 L,  5200 R. Further, the central lever  5100 , the intermediate levers  5200 L,  5200 R and the end levers  5300 L,  5300 R are straight arranged along the length of the wiper rubber  210  and are at the same height on the wiper rubber  210 . Further, in the assembled wiper blade  500 , the inclined surfaces  5121 F,  5121 R of the central spoiler portion  5120 , the inclined surfaces  5221 F,  5221 R of the intermediate spoiler portion  5220  and the inclined surfaces  5321 F,  5321 R of the end spoiler portion  5320  are straight adjoined one after another, thereby defining the spoiler  530 L,  530 R having the cross-sectional profile varying in the longitudinal direction and having a decreasing height dimension. The longitudinal end surface  5123  of the central lever  5100 , the longitudinal end surfaces  5223 ,  5224  of the intermediate lever  5200 L,  5200 R and the longitudinal end surface  5323  of the end lever  5300 L,  5300 R are inclined at an acute angle toward the distal end of the wiper blade  500 . Thus, the intermediate lever  5200 L,  5200 R and the end lever  5300 L,  5300 R cannot pivot upwardly relative to the central lever  5100 . Accordingly, when a downward load acts on the wiper blade  500 , the lever assembly  5000  brings the wiper rubber  210  into strong contact with the windshield. 
     In this embodiment, the hinge pins  5411 ,  5412  are located in the central spoiler portion  5120  and the intermediate spoiler portion  5220 , while the fitting holes  5421 ,  5422  are located in the intermediate arm  5210  and the end arm  5310 . In another embodiment, the hinge pins may be disposed in the intermediate arm  5210  and the end arm  5310 , while the fitting holes corresponding to the hinge pins may be in the arm receiving portion  5126  of the central spoiler portion  5120  and the arm receiving portion  5226  of the intermediate spoiler portion  5220 . Further, wiper blades according to other embodiments may be configured to hold the wiper rubber at four or eight pressure points by means of the above-described hinge-joint portion. That is, opposing end surfaces of two adjacent levers in the lever assembly  1000  of the first embodiment or the lever assembly  3000  of the third embodiment may be inclined toward the distal end of the wiper rubber and hinge joint between the adjacent levers may comprise the hinge pins  5411 ,  5412  and the fitting holes  5421 ,  5422 . 
       FIGS. 73 to 78  show a wiper blade  600  according to a sixth embodiment. The wiper blade  600  includes a lever assembly having an additional element that prevents the lift of the wiper blade or minimizes an eddy flow phenomenon occurring inside the lever assembly. 
     In the foregoing embodiments, since the spoiler portion of each lever of the lever assembly has an inverted V-shaped cross-section, the spoiler portion is hollow. The wiper rubber extends below each lever and has a width narrower than each lever. Thus, during running of a motor vehicle, wind or air stream can enter the interior of each lever through between the lower edge of the spoiler portion of the each lever and the wiper rubber. For example, wind or air stream can enter the interior of each lever through between the wiper rubber and a lower edge of the inclined surface, which faces forward when a motor vehicle runs. The entering wind or air stream impinges against the inclined surface facing backward and then eddies inside the lever. As a result, during running of the motor vehicle, an eddy flow may occur inside each lever. Such an eddy flow may lift the wiper blade from a surface of a windshield. 
     The lever assembly of the wiper blade  600  has an air hole at each lever. The air hole allows the wind or air stream within each lever to flow out of the lever. The air hole is formed in the inclined surface of each lever, which faces backward during running of a motor vehicle. Such an air hole may be employed to all the wiper blades  100 ,  200 ,  300 ,  400 ,  500  according to the first to fifth embodiments. In  FIGS. 73 to 76 , the same elements or components as those of the wiper blade  200  of the second embodiment are denoted by the same reference numerals. 
     Referring to  FIGS. 73 to 75 , a lever assembly  6000  of the wiper blade holds and supports the wiper rubber assembly  210 ,  220 . The spoiler  230 L,  230 R that extends in the longitudinal direction of the wiper rubber is integrally formed in the lever assembly  6000 . The lever assembly  6000  includes the central lever  1100  centrally located in the wiper rubber assembly  210 ,  220 , the intermediate levers  2200 L,  2200 R hinge-jointed to the both longitudinal ends of the central lever  1100  respectively and the end levers  2300 L,  2300 R hinge-jointed to the longitudinal ends of the intermediate levers  2200 L,  2200 R respectively. The spoiler  230 L,  230 R comprises spoiler sections integrated in the respective levers. That is, the central spoiler  131 L,  131 R is integrated in the central lever  1100 , and the intermediate spoiler  232 L,  232 R is integrated in the intermediate lever  2200 L,  2200 R, and the end spoiler  233 L,  233 R is integrated in the end lever  2300 L,  2300 R. The central spoiler  131 L,  131 R is defined by a pair of the inclined surfaces  1121 F,  1121 R of the central spoiler portion  1120 . The intermediate spoiler  232 L,  232 R is defined by a pair of the inclined surfaces  2221 F,  2221 R of the intermediate spoiler portion  2220 . The end spoiler  233 L,  233 R is defined by a pair of the inclined surfaces  2321 F,  2321 R of the end spoiler portion  2320 . The inclined surfaces  1121 F,  2221 F,  2321 F among said inclined surfaces are a forward inclined surface that faces forward in a running direction of a motor vehicle, while the inclined surfaces  1121 R,  2221 R,  2321 R are a backward inclined surface, which is opposite to the forward inclined surface and faces backward in the running direction of a motor vehicle. 
     The above-described air hole is provided in the backward inclined surface. Specifically, two air holes  6511 ,  6512  are provided in the inclined surface  1121 R of the central lever  1100  and the inclined surface  2221 R of the intermediate lever  2200 L,  2200 R, respectively. The air hole  6511 ,  6512  is a through hole perforated in the lateral surfaces of the spoiler portion  1120 ,  2220 , at which the inclined surface  1121 R,  2221 R is located. The air hole  6511  is located in the inclined surface  1121 R of the central lever between its upper edge and its lower edge. The air hole  6512  is located in the inclined surface  2221 R of the intermediate lever between its upper edge and its lower edge. In  FIGS. 73 to 75 , the air hole  6511 ,  6512  generally has a parallelogram shape. In other embodiment, the air hole  6511 ,  6512  may have a shape of a rectangle, a circle, an ellipse, etc. Further, in other embodiment, the above-described air hole may be formed in the inclined surface  2321 R of the end lever  2300 L,  2300 R. 
     The air hole  6511 ,  6512  allows the wind or air stream, which enters the interior of each lever, to flow out of each lever. For example, referring to  FIG. 76  and assuming that a motor vehicle runs with the wiper blade  600  placed on the windshield surface, the flow of air or wind around the wiper blade  600  may be divided into the following two flows: a flow F 1  crossing over the spoiler portion (in  FIG. 76 , the inclined surface  2221 F defining the intermediate spoiler  232 R); and a flow F 2  flowing to the interior of the lever (in  FIG. 76 , the intermediate lever  2200 R) through between the lower edge of the spoiler portion (the lower edge of the inclined surface  2221 F) and the wiper rubber  210 . The flow F 2  flows to the interior of the intermediate lever  2200 R and then flows out of the inclined surface  2221 R of the intermediate lever  2200 R through the air hole  6512 . A portion of the flow F 2  may impinge against the inner surface of the intermediate lever  2200 R above the air hole  6512  to thus form an eddy flow and then form a flow F 3  that flows out of the intermediate lever  2200 R through between the lower edge of the inclined surface  2221 R and the wiper rubber  210 . As described above, most of the flow F 2 , which enters the interior of the lever through the lower edge of the spoiler portion, flows out of the lever through the air hole  6511 ,  6512 , thus minimizing the occurrence of the eddy flow inside the lever. 
       FIGS. 77 and 78  show another example of the air hole. Referring to  FIG. 77 , the air holes  6521 ,  6522 ,  6523  are formed in the central lever  1100 , the intermediate lever  2200 L,  2200 R and the end lever  2300 L,  2300 R respectively. In this example, the air hole  6521 ,  6522 ,  6523  is an opening that is cut away in a semi-elliptical shape from the lower edge of the spoiler portion  1120 ,  2220 ,  2320  with the backward inclined surface  1121 R,  2221 R,  2321 R. Referring to  FIG. 78 , most of the flow F 2 , which flows into the interior of the intermediate lever  2200 R through between the lower edge of the inclined surface  2221 F of the intermediate lever  2200 R and the wiper rubber  210 , flows out of the inclined surface  2221 R of the intermediate lever  2200 R through the air hole  6522 . Only the partial flow F 3  of the flow F 2 , which impinges against the inner surface of the intermediate lever  2200 R above the air hole  6522 , makes the eddy flow and then flows out of the inclined surface  2221 R of the intermediate lever  2200 R through the air hole  6522 . As described above, most of the flow F 2 , which enters the interior of the lever through the lower edge of the spoiler portion, flows out of the lever through the air hole  6521 ,  6522 ,  6523 , thus minimizing the occurrence of the eddy flow inside the lever. 
       FIGS. 79 to 81  show a wiper blade  700  according to a seventh embodiment. A lever assembly of the wiper blade  700  according to this embodiment is configured to prevent wind or air stream from entering the interior of the lever assembly during running of a motor vehicle. 
     The lever assembly of the wiper blade  700  includes a covering member at its underside. The covering member covers the interior of the lever assembly or its lever, thus preventing wind or air stream from entering the interior of the lever of the lever assembly during running of a motor vehicle. Such a covering member may be employed to all the wiper blades  100 ,  200 ,  300 ,  400 ,  500  according to the foregoing first to fifth embodiments. Descriptions are made below as to the wiper blade of this embodiment by way of example wherein said covering member is employed to the lever assembly  5000  of the wiper blade  500  according to the fifth embodiment. 
     Referring to  FIGS. 79 and 80 , the lever assembly  5000  of the wiper blade  700  includes the covering member  750  that is coupled to the underside of the lever assembly  5000  in the longitudinal direction. The covering member  750  is elongated to correspond to a plane shape of the underside of the lever assembly  5000  and comprises a sheet body made from a plastic or metallic material. The covering member  750  may comprise a single one elongated piece extending along the length of the lever assembly  5000  or a plurality of single pieces as many as levers constituting the lever assembly  5000 . In this embodiment, the covering member  750  comprises a plurality of covering sheets corresponding to each lever of the lever assembly  5000  respectively. 
     The covering member  750  comprises a central covering sheet  7510  coupled to the underside of the central lever  5100 , an intermediate covering sheet  7520  coupled to the underside of the intermediate lever  5200 L,  5200 R, and an end covering sheet  7530  coupled to the underside of the end lever  5300 L,  5300 R. Each covering sheet may be coupled to the associated lever in various manners and such coupling between the covering sheet and the lever is not limited to the particular manner. For example, the covering sheet may be coupled to the lever through snap-engagement, fitting, attachment, etc. As to snap-engagement, opposing edges of the underside of each lever may be provided with hook-shaped elements capable of hooking the edges of the corresponding covering sheet therein. As to fitting, the opposing edges of the underside of each lever may be provided with a pair of rails or grooves and the covering sheet may be fitted to those rails or grooves. As to attachment, the covering sheet may be adhered to the associated lever by means of adhesive. 
     Each covering sheet is configured to substantially cover the interior of the associated lever at the underside of the associated lever. Further, each covering sheet is configured not to interfere with the arm and the clamp of the lever. The central covering sheet  7510  has, at its longitudinal sides, slits  7511  for avoiding interference with the intermediate arm  5210  and the clamp  5211  of the intermediate lever  5200 L,  5200 R. The slit  7511  extends inwardly from an end of the central covering sheet  7510  and is configured to accommodate the intermediate arm  5210  and the clamp  5211 . When the central covering sheet  7510  is coupled to the central lever  5100  in the lever assembly  5000  with its levers adjoined one after another, the intermediate arm  5210  and the clamp  5211  of the intermediate lever  5200 L,  5200 R are situated in the slit  7511 . The intermediate covering sheet  7520  includes a pair of sheets. Opposing edges of the sheets are formed with a notch  7521  for avoiding interference with the clamp  5311  of the end lever  5300 L,  5300 R. When the intermediate covering sheet  7520  is coupled to the intermediate lever  5200 L,  5200 R in the lever assembly  5000  with its levers adjoined one after another, the clamp  5311  of the end lever  5300 L,  5300 R is situated between a pair of the notches  7521 . The end covering sheet  7530  has a portion  7531 , which is located in the underside of the end lever  5300 L,  5300 R, and an extension portion  7532  extending from the portion  7531  toward the intermediate covering sheet  7520 . The extension portion  7532  extends up to the notch  7521  between the sheets of the intermediate covering sheet  7520 . When the end covering sheet  7530  is coupled to the end lever  5300 L,  5300 R in the lever assembly  5000  with its levers adjoined one after another, the portion  7531  is coupled to the underside of the end lever  5300 L,  5300 R and the extension portion  7532  is placed below a portion of the end lever  5310 . 
     If the central covering sheet  7510 , the intermediate covering sheet  7520  and the end covering sheet  7530  are coupled to the respective associated levers, then the interior of the lever assembly  5000  is substantially covered by the covering sheets. Thus, those covering sheets prevent wind or air stream from entering each lever of the lever assembly  5000 . For example, referring to  FIG. 81  and assuming that a motor vehicle runs with the wiper blade  700  placed on the windshield surface, the flow of air or wind around the wiper blade  700  may be divided into the following two flows: a flow F 1  crossing over the upper surface of the lever (in  FIG. 81 , the end lever  5300 L); and a flow F 2  passing by the underside of the lever (in  FIG. 81 , the end lever  5300 L). The flow F 2  cannot enter the interior of the lever or the lever assembly due to the covering sheet located at the underside of the lever (in  FIG. 81 , the end covering sheet). Accordingly, since wind or air stream does not enter the interior of the lever assembly  5000  during running of a motor vehicle, the wiper blade  700  can be brought into strong contact with windshield surface under the reaction force produced by the spoiler  530 L,  530 R. 
     In the foregoing embodiments, the spoiler  130 L,  130 R,  230 L,  230 R,  330 L,  330 R,  430 L,  430 R,  530 L,  530 R integrated in the lever assembly has the cross-section profile of a triangle with both concave legs. The wiper blade of the present invention may have a cross-sectional profile other than the above-described cross-section profile. For example, as shown in  FIG. 82 , a spoiler  830 L,  830 R integrated in the lever assembly may have a cross-sectional profile, a height dimension of which is constant from the center of the wiper blade to its distal end. Further, as shown in  FIG. 83 , a cross-sectional profile of a spoiler  930  integrated in the lever assembly may include a triangle with both convex legs, a semicircle, or a semi-oval. That is, the cross-sectional profile of the spoiler  930  may include a pair of convex curves that are symmetrical in the width direction of the lever assembly. 
     In the foregoing first to third embodiments, the hinge-joint portion  1400 L,  1400 R,  2400 L,  2400 R,  2400 ′L,  2400 ′R,  3400 L,  3400 R,  3400 ′L,  3400 ′R comprises a rivet joint. By way of another example of the hinge-joint portion, the hinge-joint portion comprises a pin joint using a pin instead of a rivet. In such an example, the joint cover  1430 ,  1430 ′ may have an element for fixing the pin therein. 
     Further, in other embodiment, a portion of one of two adjacent levers may be situated within a spoiler portion of the other of the two adjacent levers, which is further outward than said one of the two adjacent levers. That is, the central lever may include an arm extending toward the distal end of the wiper blade. Further, the intermediate lever or the end lever, which adjoins the central lever, may include a spoiler portion, which forms the spoiler section and hides the arm of the central lever, and an arm, which extends from the spoiler portion toward the distal end of the wiper blade and has a clamp at its distal end. 
     Although embodiments have been described with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the principles of this disclosure. More particularly, numerous variations and modifications are possible in the component parts and/or arrangements of the subject combination arrangement within the scope of the disclosure, the drawings and the appended claims. In addition to variations and modifications in the component parts and/or arrangements, alternative uses will also be apparent to those skilled in the art.