Abstract:
A wiper for a vehicle is provided with: an arm-side connection section; a blade-side connection section; support shafts which protrude from side walls of the blade-side connection section; and shaft support recesses which are provided in the arm-side connection section. When a wiper blade is located in a mounting-dismounting enabled region, the mounting-dismounting openings and the small-diameter sections of the support shafts match with each other, and the support shafts and the shaft support recesses can be mounted to and dismounted from each other. When the wiper blade is located in a mounting-dismounting disabled region, the mounting-dismounting openings and the small-diameter sections do not match with each other, and the support shafts and the shaft support recesses cannot be mounted to and dismounted from each other. A shape retaining section is located between the pair of the shaft support recesses.

Description:
RELATED APPLICATIONS 
       [0001]    The present application is a National Phase entry of PCT Application No. PCT/JP2013/078693, filed Oct. 23, 2013, which application claims priority to Japanese Application No. 2012-234900, filed Oct. 24, 2012, both of said applications being hereby incorporated by reference in their entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to a vehicle wiper that wipes a windshield and a rear window of a vehicle. 
       BACKGROUND OF THE INVENTION 
       [0003]    In a conventional vehicle wiper, a wiper blade is pivotally coupled to a distal end of a wiper arm so that the wiper blade can follow along a curved wiping surface. For example, in the vehicle wiper of patent document 1, a coupling hole, which extends through the distal end of the wiper arm, is pivotally coupled, through elastic engagement, to a support shaft formed on the wiper blade. In such a structure, the elastic engagement, which couples between the support shaft and the coupling hole facilitates the attachment and separation of the wiper arm and the wiper blade. However, the low coupling force between the support shaft and the coupling hole may result in unexpected separation of the coupled components. 
         [0004]    To solve such a problem, patent document 2 describes a known example of a vehicle wiper. In the vehicle wiper of patent document 2, the support shaft of the wiper blade includes a small diameter portion located at a predetermined angular position. The small diameter portion has a smaller radial dimension than the diameter of the shaft. The arm side coupling hole includes an attachment-separation port (opening). The attachment-separation port has a dimension that is smaller than the diameter of the support shaft and larger than the small diameter portion. When the wiper blade is pivoted to a position corresponding to where the small diameter portion of the support shaft corresponds to the attachment-separation port of the coupling hole, the support shaft becomes attachable to and separable from the coupling hole. Attachment and separation of the support shaft from the coupling hole is disabled by pivoting the wiper blade about the support shaft from the attachable-separable position to a wiper usage position where the small diameter portion of the support shaft and the attachment-separation port of the coupling hole are not located in correspondence with each other. In such a structure, attachment and separation of the wiper blade is facilitated. Further, in the normal usage state, the wiper blade is rigidly coupled to and supported by the wiper arm to obviate unexpected separation of the wiper blade from the wiper arm. 
       SUMMARY OF THE INVENTION 
       [0005]    In the vehicle wiper described in patent document 2, to reduce the size of wiper blade in the heightwise direction (direction perpendicular to the wiping surface), the portion coupling the wiper arm and the wiper blade may be reduced in height without changing the diameters of the support shaft and the coupling hole. This would reduce the thickness around the coupling hole at the distal end of the wiper arm. Thus, if the wiper arm were to be formed, in particular, from resin or the like, deformation may result in a tendency of easy opening of the attachment-separation port in the coupling hole, which is used for attachment and separation of the support shaft. The support shaft may thus fall out of the attachment-separation port of the coupling hole even if the wiper blade is located at the normal usage position. Hence, in the coupling structure of the support shaft described in patent document 2, it was difficult to reduce the size of the wiper blade in the heightwise direction. 
         [0006]    Accordingly, it is an object of the present invention to provide a vehicle wiper capable of limiting opening of the attachment-separation port of the coupling hole while reducing the size in the heightwise direction. 
         [0007]    To achieve the above object, one aspect of the present invention is a vehicle wiper including a wiper arm, an arm side coupling portion arranged on a distal end of the wiper arm, a wiper blade, a blade side coupling portion arranged on the wiper blade and pivotally coupled to the arm side coupling portion, and two side walls arranged on one of the arm side coupling portion and the blade side coupling portion. The two side walls face each other. Two support shafts respectively project from inner side surfaces of the two side walls. The two support shafts are coaxial with each other. Two shaft support recesses are arranged on the other one of the arm side coupling portion and the blade side coupling portion. The two support shafts are pivotally fitted to the two shaft support recesses, respectively. Each of the support shafts has a small diameter portion located at a predetermined angular position of the wiper arm relative to the wiper blade, and the small diameter portion has a smaller radial dimension than the diameter of the support shaft. Each of the shaft support recesses includes an attachment-separation port, and the attachment-separation port has a dimension that is smaller than the diameter of the support shaft and larger than the radial dimension of the small diameter portion. An attachable-separable region and a non-attachable-separable region are set as angular regions of the wiper blade relative to the wiper arm. When the wiper blade is in the attachable-separable region, the attachment-separation port and the small diameter portion of the support shaft are in correspondence with each other thereby enabling attachment and separation of the support shafts and the shaft support recesses. When the wiper blade is pivoted about the support shaft from the attachable-separable region to a wiper usage position and the wiper blade is in the non-attachable-separable region, the attachment-separation port and the small diameter portion are not in correspondence with each other thereby disabling attachment and separation of the support shafts and the shaft support recesses. The arm side coupling portion or the blade side coupling portion that includes the shaft support recesses includes a shape sustaining portion that sustains the shape of the attachment-separation port, and the shape sustaining portion is located between the two shaft support recesses. 
         [0008]    In this structure, the support shafts and a coupling hole that pivotally couple the wiper blade and the wiper arm are divided in the axial direction. Thus, the coupling hole that supports the support shaft does not need to be a through hole. Further, the shape sustaining portion located between the divided coupling holes (two shaft support recesses) sustains the shape of the attachment-separation port. Thus, even if the coupling portion of the wiper arm and the wiper blade is reduced in size in the heightwise direction (direction perpendicular to the wiping surface), the attachment-separation port of the shaft support recess does not easily open. Thus, when the wiper blade is at the usage position (i.e., when the pivot position of the wiper blade relative to the wiper arm is in the non-attachable-separable region), the support shafts are rigidly coupled to the shaft support recesses. Further, when attachment and separation is necessary such as for maintenance, the support shafts and the shaft support recesses may be easily attached to and separated from one another by simply pivoting the wiper blade to the attachable-separable region. 
         [0009]    Preferably, in the vehicle wiper, the wiper blade and the wiper arm respectively include a blade side engagement portion and an arm side engagement portion that are elastically engaged with each other to limit pivoting of the wiper blade in the non-attachable-separable region. 
         [0010]    In such a structure, elastic engagement of the blade side engagement portion and the arm side engagement portion limits free pivoting of the wiper blade in the non-attachable-separable. This obviates the wiper blade hitting the vehicle body, the wiping surface, or the like when the wiper arm  11  that would be caused by unexpected pivoting of the wiper blade when the wiper arm is locked back (held upright with respect to the wiping surface) during maintenance or the like. Further, unexpected separation of the wiper blade and the wiper arm may be prevented when the wiper blade is in the attachable-separable region. 
         [0011]    Preferably, in the vehicle wiper the blade side engagement portion and the arm side engagement portion are arranged toward a basal side of the wiper arm from the support shafts and the shaft support recesses. 
         [0012]    In such a structure, the arm side engagement portion is easily formed in the main body of the wiper arm. This simplifies the structures of the blade side engagement portion and the arm side engagement portion. 
         [0013]    Preferably, in the vehicle wiper, the wiper blade includes a blade rubber that wipes a wiping surface, and a rubber holding portion that holds the blade rubber. The rubber holding portion and the blade side coupling portion are integrally formed to configure a holder member. 
         [0014]    In such a structure, the holder member of the wiper blade is coupled to the distal end of the wiper arm (arm side coupling portion) and holds the blade rubber that wipes the wiping surface. That is, the coupling of the blade rubber to the arm side is completed with the same holder member. Thus, the wiper blade may easily be reduced in size in the heightwise direction compared to a structure that holds the blade rubber with a lever assembly including levers coupled in the form of a whippletree. 
         [0015]    Preferably, in the vehicle wiper, the wiper arm includes an upper wall and side walls, which extend toward the wiping surface from two widthwise ends of the upper wall. The widthwise ends are ends of the upper wall arranged in a widthwise direction of the wiper. The upper wall includes a load receiving unit capable of contacting the blade side coupling portion in the widthwise direction of the wiper. 
         [0016]    In such a structure, when load in the wiper widthwise direction is applied to the wiper blade (e.g., when the wiper is driven with the blade rubber frozen onto the wiping surface, load is received by the load receiving unit through the blade side coupling portion. This limits separation of the support shafts from the shaft support recesses that would occur when the distance is increased in the widthwise direction between the side walls of the wiper arm due to load. As a result, separation of the wiper blade may be limited. 
         [0017]    The present invention provides a vehicle wiper capable of limiting opening of the attachment-separation port of the coupling hole while reducing the size in the heightwise direction. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]      FIG. 1  is a perspective view showing one embodiment of a vehicle wiper. 
           [0019]      FIG. 2  is a cross-sectional view of the vehicle wiper shown in  FIG. 1 . 
           [0020]      FIG. 3  is a cross-sectional view of the wiper shown in  FIG. 1  illustrating a wiper arm and a holder member at a wiper usage position. 
           [0021]      FIG. 4  is a cross-sectional view of the wiper shown in  FIG. 1  illustrating the wiper arm and the holder member when an arm side coupling portion and a blade side coupling portion are in engagement. 
           [0022]      FIG. 5  is a cross-sectional view of the wiper shown in  FIG. 1  illustrating attachment and separation of the wiper arm and the holder member. 
           [0023]      FIG. 6  is a cross-sectional view of a further example of a vehicle wiper. 
           [0024]      FIG. 7  is a cross-sectional view of the wiper shown in  FIG. 6  illustrating a wiper arm and a holder member at a wiper usage position. 
           [0025]      FIG. 8  is a cross-sectional view of the wiper shown in  FIG. 6  illustrating the wiper arm and the holder member when an arm side coupling portion and a blade side coupling portion are in engagement. 
           [0026]      FIG. 9  is a cross-sectional view of the wiper shown in  FIG. 6  illustrating attachment and separation of the wiper arm and the holder member. 
           [0027]      FIG. 10  is a cross-sectional view of a further example of a wiper arm and a holder member. 
           [0028]      FIG. 11  is a cross-sectional view of another example of a wiper arm and a holder member. 
           [0029]      FIG. 12  is a bottom view of the wiper shown in  FIG. 11  illustrating a wiper arm and a holder member. 
       
    
    
     DETAILED DESCRIPTION 
       [0030]    One embodiment of a vehicle wiper will now be described. 
         [0031]    As shown in  FIG. 1 , a vehicle wiper  10  according to the present embodiment wipes raindrops or the like from the surface (wiping surface G) of a rear window of a vehicle. The vehicle wiper  10  includes a wiper arm  11 , which is formed from resin, and a wiper blade  12 , which is pivotally coupled to the distal end of the wiper arm  11  and arranged in contact with the wiping surface G. 
         [0032]    The wiper arm  11  includes a basal end coupled to an arm head  11   a , which is fixed to a pivot shaft (not shown). A wiper motor (not shown) drives and pivots the pivot shaft to swing back and forth the wiper arm  11  and the wiper blade  12 . The swinging wiper blade  12  wipes the wiping surface G. A spring (not shown), which generates a pushing force pushing the wiper blade  12  against the wiping surface G, is attached to the wiper arm  11 . 
         [0033]    The wiper blade  12  includes a resin holder member  13 , which is coupled to the wiper arm  11 , a backing  14  and a blade rubber  15 , which are held by the holder member  13 , and two cases  16 , which are attached to the backing  14  and the blade rubber  15 . A cap  17 , which prevents the cases  16  and the blade rubber  15  from falling out of the wiper blade  12 , is attached to each of the two longitudinal ends of the wiper blade  12 . 
         [0034]    As shown in  FIG. 2 , the blade rubber  15  is elongated and formed from an elastic rubber material or an elastomer. The blade rubber  15  is formed to be symmetric to a center line in the widthwise direction (lateral direction in  FIG. 2 ) and have a uniform cross-sectional shape in the longitudinal direction. The blade rubber  15  includes an upper portion defining a head portion  21 , which is held by the case  16 , and extending over the entire longitudinal direction of the blade rubber  15 . 
         [0035]    The head portion  21  is flat and thin in the heightwise direction (direction perpendicular to the wiping surface G). A coupling portion  22  extends downward from the middle of the head portion  21  in the widthwise direction. A portion below the head portion  21  defines an extending portion  23 , which is thinner than the head portion  21  in the heightwise direction and coupled to the head portion  21  by the coupling portion  22 . The extending portion  23  extends from the lower end of the coupling portion  22  to two sides in the widthwise direction of the blade rubber  15 . The coupling portion  22 , which is thinner in the widthwise direction than the head portion  21  and the extending portion  23 , form a constricted portion  24  (holding groove), which is depressed toward the inner side from two widthwise side surfaces. 
         [0036]    A neck portion  25  extends from the lower surface of the extending portion  23 . A portion below the blade rubber  15  defines a wiping portion  26  connected to the extending portion  23  by the neck portion  25 . The neck portion  25  is defined at the middle of the blade rubber  15  in the widthwise direction and formed to be narrower than the coupling portion  22 . The wiping portion  26  is tapered to narrow from the upper part (end at the side of the neck portion  25 ) toward the lower part and has substantially the same width as the neck portion  25  at the lower end. Deformation of the neck portion  25  allows the wiping portion  26  to tilt in the widthwise direction relative to the head portion  21 . The extending portion  23  is entirely wider than the head portion  21  to contact the shoulder of the wiping portion  26  when the wiping portion  26  is tilted. The contact restricts the tilt position of the wiping portion  26 . 
         [0037]    The backing  14 , which is formed from a metal plate spring material, is arranged above the head portion  21  of the blade rubber  15  (non-wiping surface side). The backing  14  is elongated in the longitudinal direction of the blade rubber  15  and set to have the same length as the blade rubber  15 . The backing  14  is arranged such that its plate surface extends in a direction orthogonal to the heightwise direction of the blade rubber  15 . The backing  14  contacts the upper surface of the head portion  21  (end surface at the non-wiping surface side) in the heightwise direction of the blade rubber  15 . The backing  14  is set to be wider than the head portion  21 . The two widthwise ends of the backing  14  each project toward the outer side in the widthwise direction from the head portion  21 . 
         [0038]    The coupling of the holder member  13 , which is arranged at the middle of the wiper arm  11  in the longitudinal direction, with the wiper arm  11  will now be described. 
         [0039]    As shown in  FIGS. 1 and 2 , the distal end of the wiper arm  11  defines an arm side coupling portion  31  and the holder member  13  includes a blade side coupling portion  41 . The coupling portions  31  and  41  are pivotally coupled to each other. 
         [0040]    The arm side coupling portion  31  is formed to be narrower than a main body  11   b  of the wiper arm  11  (see  FIG. 1 ). A shaft support recess  32  depressed toward the inner side in the widthwise direction is formed in each of the two widthwise side surfaces of the arm side coupling portion  31 . A shape sustaining wall  33  is formed between the shaft support recesses  32 . The arm side coupling portion  31  is symmetric in shape in the widthwise direction with the shape sustaining wall  33  located in the center. The shaft support recesses  32  at the widthwise sides of the shape sustaining wall  33  are identical in shape and are concentric with each other. 
         [0041]    As shown in  FIG. 3 , the shaft support recesses  32 , which are formed to be arcuate, are coaxial and have the same diameter. The blade side coupling portion  41  includes a support shaft  43 , which will be described later and is pivotally supported by the shaft support recesses  32 . The axis of each shaft support recess  32  is set to be parallel with the widthwise direction of the wiper blade  12 . A portion peripheral to each shaft support recess defines an attachment-separation port  34  used to attach and separate the support shaft  43  to and from the shaft support recess  32 . Each shaft support recess  32  opens toward the distal side in the longitudinal direction of the wiper blade  12  (side distant from the basal end of the wiper arm  11 ) through the attachment-separation port  34 . The attachment-separation port  34  is formed so that the opening widens toward the distal end of the arm side coupling portion  31 . 
         [0042]    A shape sustaining wall  33  is formed between the two shaft support recesses  32  and the attachment-separation port  34  in the widthwise direction to integrally connect an upper wall  35  and a lower wall  36  forming each of the shaft support recesses  32  and the attachment-separation port  34  in the heightwise direction of the wiper blade  12  (direction perpendicular to the wiping surface G). The shape sustaining wall  33  prevents the upper wall  35  and the lower wall  36  from moving away from each other. That is, the shape sustaining wall  33  functions to couple the upper wall  35  and the lower wall  36  to each other and hold the shape of the attachment-separation port  34  in the shaft support recesses  32  so that the attachment-separation port  34  does not open. 
         [0043]    As shown in  FIGS. 2 and 3 , the blade side coupling portion  41  includes two side walls  42 , which face each other in the widthwise direction (pivot shaft direction), and two support shafts  43 , which project from the inner surfaces of the side walls  42  and are coaxial with each other. The side walls  42  are arranged at the two widthwise sides of the arm side coupling portion  31  and are formed so that the outer surfaces of the side walls  42  are flush with the widthwise side surfaces of the main body  11   b  of the wiper arm  11  (see  FIG. 1 ). The space between the side walls  42  opens toward the upper side (non-wiping surface side) to allow the arm side coupling portion  31  to be coupled. 
         [0044]    The two support shafts  43 , which are formed integrally with the side walls  42 , are identical in shape. Each support shaft  43  includes an arcuate portion  43   a , which has a diameter corresponding to the inner diameter of the shaft support recess  32 , and a (D-shaped) small diameter portion  43   b , which has a smaller diameter than the arcuate portion  43   a . The arcuate portion  43   a  is defined by the circumferential surface of the support shaft  43  extending over one half or greater of the circumference. The remaining circumferential surface forms the small diameter portion  43   b . The attachment-separation port  34  of the shaft support recess  32  is smaller in diameter than the support shaft  43  (diameter of the arcuate portion  43   a ) and larger in the radial direction than the small diameter portion  43   b.    
         [0045]    This allows the support shafts  43  and the shaft support recesses  32  to be attached to and separated from one another by relatively pivoting the wiper blade  12  and the wiper arm  11  to a position where the small diameter portion  43   b  of the support shaft  43  corresponds to the attachment-separation port  34  (see  FIG. 5 ). The attachment and separation of the support shafts  43  and the shaft support recesses  32  are disabled by relatively pivoting the wiper blade  12  about the support shaft  43  from a attachable-separable region, where the attachment-separation port  34  corresponds to the small diameter portion  43   b  of the support shaft  43 , to the wiper usage position shown in  FIG. 3  so that the wiper blade  12  is located in a non-attachable-separable region where the attachment-separation port  34  does not correspond to the small diameter portion  43   b . When the wiper blade  12  is located in the non-attachable-separable region, the arcuate portion  43   a  contacts the wall surface of the shaft support recess  32 . 
         [0046]    As shown in  FIGS. 2 and 3 , the blade side coupling portion  41  includes a rubber holding portion  44  extending toward the lower side (side of wiping surface G) of the blade side coupling portion  41 . The rubber holding portion  44  is substantially tubular and extends in the longitudinal direction of the blade rubber  15  and hold the head portion  21  of the blade rubber  15  and the longitudinal central part of the backing  14 . 
         [0047]    In detail, the rubber holding portion  44  includes an upper cover  45 , which covers the upper surface (surface on the anti-blade rubber side) of the backing  14 , and a holding piece  46 , which extends from each of the two widthwise ends of the upper cover  45  to that hold the backing  14  and the head portion  21 . The distal end of each holding piece  46  is fitted to the corresponding constricted portion  24  below the head portion  21 . In other words, the coupling portion  22  of the blade rubber  15  is fitted to a groove between the distal ends of the holding pieces  46 . Thus, the head portion  21  is engaged with the distal end of each holding piece  46  in the heightwise direction of the blade rubber  15 . The backing  14  is accommodated in an accommodation space formed between the upper cover  45 , the holding pieces  46 , and the head portion  21 . 
         [0048]    Thus, the rubber holding portion  44  surrounds and holds the backing  14  and the head portion  21  with the backing  14  in contact with the upper surface of the head portion  21 . The extending portion  23 , the neck portion  25 , and the wiping portion  26  of the blade rubber  15  are exposed from the lower side (wiping surface G side) of the rubber holding portion  44 . A stopper (not shown) is engaged with the longitudinally central portion of the backing  14  to restrict movement of the backing  14  in the longitudinal direction. 
         [0049]    The side walls  42  of the blade side coupling portion  41  are formed to extend to the upper side (non-wiping surface side) from the upper cover  45  of the rubber holding portion  44 . In a direction orthogonal to the longitudinal direction, the blade side coupling portion  41  has a substantially U-shaped cross-section formed by the side walls  42 , the upper cover  45 , and an open upper side. 
         [0050]    As shown in  FIG. 3 , the rubber holding portion  44  includes a blade side engagement portion  47  extending toward the upper side (non-wiping surface side) from the upper cover  45 . The blade side engagement portion  47  is located at the blade basal side (basal side in the longitudinal direction of the wiper blade  12 ) of the side walls  42  of the rubber holding portion  44 . The “blade basal side” refers to locations of the wiper blade  12  proximal to the pivot shaft at the basal end of the wiper arm  11 . An elastic piece  47   a  projects toward the basal side of the blade from the distal end of the blade side engagement portion  47 . 
         [0051]    The main body  11   b  of the wiper arm  11  has a reverse-U-shaped cross-section that opens toward the side of the wiping surface G. An arm side engagement portion  37  extending toward the lower side (side of wiping surface G) is formed in the upper wall  11   c  of the main body  11   b . An elastic piece  37   a  projects toward the distal side of the blade (side opposite to the basal end of the blade) is formed at the distal end of the blade side engagement portion  47 . The elastic piece  37   a  may be elastically engaged with the elastic piece  47   a  of the blade side engagement portion  47 . 
         [0052]    Referring to  FIG. 1 , the two cases  16  are formed from a soft (flexible) resin material. The two cases  16  are elongated in the longitudinal direction of the blade rubber  15  and are respectively arranged at the two longitudinal sides in the direction of the holder member  13 . Each case  16 , which has a structure similar to the rubber holding portion  44  of the holder member  13 , surrounds and holds the backing  14  and the head portion  21  with the backing  14  in contact with the upper surface of the head portion  21 . Hence, the longitudinally central part of the backing  14  and the head portion  21  of the blade rubber  15  is held by the rubber holding portion  44  of the holder member  13 . The two longitudinal sides of the backing  14  and the head portion  21  are held by the cases  16 . The cases  16  are formed to be in communication with each other through the rubber holding portion  44  of the holder member  13 . 
         [0053]    The operation of the present embodiment will now be described. 
         [0054]    As shown  FIG. 3 , at the wiper usage position where the wiper arm  11  is substantially parallel to the wiper blade  12 , the small diameter portion  43   b  of the support shaft  43  and the attachment-separation port  34  of the shaft support recess  32  are not in correspondence with each other. This disables attachment and separation of the support shaft  43  and the shaft support recess  32 . In such a state, the elastic piece  37   a  of the arm side engagement portion  37  is located toward the side of the wiping surface G (lower side in  FIG. 3 ) from the elastic piece  47   a  of the blade side engagement portion  47 . The wiper arm  11  and the wiper blade  12  are relatively pivotal about the support shaft  43  in a direction in which the elastic pieces  37   a  and  47   a  move toward each other. The pivoting of the wiper blade  12  in the non-attachable-separable region is enabled in a range in which the elastic pieces  37   a  and  47   a  do not come into contact. More specifically, as shown in  FIG. 4 , engagement of the arm side engagement portion  37  and the blade side engagement portion  47  limits the pivoting of the wiper blade  12  in the non-attachable-separable region. This obviates the wiper blade  12  hitting the vehicle body, the wiping surface G, or the like when the wiper arm  11  that would be caused by unexpected pivoting of the wiper blade  12  when the wiper arm  11  is locked back (held upright with respect to the wiping surface G) during maintenance or the like. Further, unexpected separation of the wiper blade  12  and the wiper arm  11  may be prevented when the wiper blade  12  is in the attachable-separable region. 
         [0055]    When the wiper blade  12  is relatively pivoted about the support shaft  43  from the position shown in  FIG. 4  by excessive force in a direction (counterclockwise direction in  FIG. 4 ) in which the main body  11   b  moves away from the rubber holding portion  44 , the arm side engagement portion  37  and the blade side engagement portion  47  are elastically deformed. Thus, the arm side engagement portion  37  moves over the blade side engagement portion  47  and is disengaged from the blade side engagement portion  47 . This cancels the pivoting limitation of the wiper arm  11  and the wiper blade  12  thereby allowing the wiper blade  12  to be relatively pivoted to the attachable-separable region where the attachment-separation port  34  corresponds to the small diameter portion  43   b  of the support shaft  43 . 
         [0056]    As shown in  FIG. 5 , in the attachable-separable region, the attachment-separation port  34  corresponds to the small diameter portion  43   b  of the support shaft  43 . This allows for attachment and separation of the support shaft  43  and the shaft support recess  32 . Thus, when the wiper blade  12  needs to be separated and attached such as during maintenance, the support shaft  43  and the shaft support recess  32  may be easily separated and attached by simply disengaging the arm side engagement portion  37  and the blade side engagement portion  47  and pivoting the wiper blade  12  to the attachable-separable region. 
         [0057]    Thus, the pivotal coupling of the support shaft  43 , which is D-shaped, and the shaft support recess  32 , allows for the coupling of the support shaft  43  and the shaft support recess  32  when the wiper blade  12  is in the usage position. When attachment and separation need to be performed for such as during maintenance, the support shaft  43  and the shaft support recess  32  may be easily attached and separated just by pivoting the wiper blade  12  to the attachable-separable region. 
         [0058]    The arm side coupling portion  31  of the present embodiment includes the two shaft support recess  32 , to which the two support shafts  43  of the blade side coupling portion  41  are pivotally fitted, and the shape sustaining wall  33  between the shaft support recesses  32 . That is, the support shaft  43  and the coupling hole that pivotally couple the wiper blade  12  and the wiper arm  11  are divided in the axial direction. Thus, there is no need for the coupling hole that supports the support shaft  43  to be a through hole. The shape sustaining wall  33 , which is located between the divided coupling hole (two shaft support recesses  32 ), integrally connects the upper wall  35  and the lower wall  36  to form the attachment-separation port  34  and sustains the shape of the attachment-separation port  34  is held. Thus, even if each of the coupling portions  31  and  41  is reduced in size in the heightwise direction (direction perpendicular to the wiping surface G), the attachment-separation port  34  of the shaft support recess  32  does not easily open. This further rigidly couples the support shaft  43  and the shaft support recess  32  when the wiper blade  12  is at the usage position. 
         [0059]    The characteristic effects (advantages) of the present embodiment will now be described. 
         [0060]    (1) The blade side coupling portion  41  includes the two side walls  42 , which face each other in the wiper widthwise direction (direction of pivot axis), and two support shafts  43 , which project from the inner surfaces of the side walls  42  and are coaxial with each other. The arm side coupling portion  31  includes the two shaft support recesses  32 , to which the two support shafts  43  are pivotally fitted. The arm side coupling portion  31  includes the shape sustaining wall  33  (shape sustaining portion) located between the two shaft support recesses  32  to sustain the shape of the attachment-separation port  34 . In such a structure, the support shafts  43  and the coupling hole that pivotally couple the wiper blade  12  and the wiper arm  11  are divided in the axial direction. Thus, the coupling hole that supports the support shaft  43  does not need to be a through hole. The shape of the attachment-separation port  34  is sustained by the shape sustaining wall  33  located between the divided coupling holes (two shaft support recesses  32 ). Thus, even if the coupling portion of the wiper arm  11  and the wiper blade  12  is reduced in size in the heightwise direction (direction perpendicular to the wiping surface G), the attachment-separation port  34  of the shaft support recess  32  does not easily open. 
         [0061]    Each support shaft  43  includes the small diameter portion  43   b  located at a predetermined angular position of the wiper arm  11  relative to the wiper blade  12 . The small diameter portion  43   b  has a smaller radial dimension than the diameter of the support shaft  43 . Each of the shaft support recesses  32  includes the attachment-separation port  34 , which has a smaller dimension than the diameter of the support shaft  43  and a larger dimension than the radial dimension of the small diameter portion  43   b . The attachable-separable region and the non-attachable-separable region are set as at angular regions of the wiper blade  12  relative to the wiper arm  11 . When the wiper blade  12  is in the attachable-separable region, the attachment-separation port  34  and the small diameter portion  43   b  of the support shaft  43  are in correspondence, and the support shaft  43  and the shaft support recess  32  are attachable and separable to and from each other. When the wiper blade  12  is pivoted about the support shaft  43  from the attachable-separable region to the wiper usage position and the wiper blade  12  is in the non-attachable-separable region, the attachment-separation port  34  and the small diameter portion  43   b  are not in correspondence and the support shaft  43  and the shaft support recess  32  are not attachable and separable to and from each other. 
         [0062]    (2) The wiper blade  12  and the wiper arm  11  respectively include the blade side engagement portion  47  and the arm side engagement portion  37  that limit pivoting of the wiper blade  12  in the non-attachable-separable region through elastic engagement with each other. In such a structure, free pivoting of the wiper blade  12  in the non-attachable-separable region is limited by the elastic engagement of the blade side engagement portion  47  and the arm side engagement portion  37 . Thus, when the wiper arm  11  is locked back (held upright with respect to the wiping surface G), the wiper blade  12  is prevented from hitting the wiping surface G and the like that would be caused by unexpected pivoting. In addition, when the wiper blade  12  reaches the attachable-separable region, unexpected separation of the coupled wiper blade  12  and wiper arm  11  is obviated. 
         [0063]    (3) The blade side engagement portion  47  and the arm side engagement portion  37  are arranged toward the basal side of the wiper arm  11  from the support shaft  43  and the shaft support recess  32 . In such a structure, the arm side engagement portion  37  is formed with further ease in the main body  11   b  of the wiper arm  11 . This simplifies the structures of the blade side engagement portion  47  and the arm side engagement portion  37  are compared to when the engagement portion is arranged in each of the support shaft  43  and the shaft support recess  32 . Further, the engagement portion is spaced apart from the pivot axis of the wiper blade  12  and the wiper arm  11  (axis of the support shaft  43  and the shaft support recess  32 ). This limits free pivoting of the wiper blade  12  relative to the wiper arm  11  that would be caused by a small force. 
         [0064]    (4) The wiper blade  12  includes the blade rubber  15 , which wipes the wiping surface G, and the rubber holding portion  44 , which holds the blade rubber  15 . The rubber holding portion  44  and the blade side coupling portion  41  are formed integrally to form the holder member  13 . Thus, the coupling of the blade rubber  15  to the arm side is achieved with the same holder member  13 . This allows the wiper blade  12  to be easily reduced in size in the heightwise direction compared to the conventional structure that holds the blade rubber  15  with a lever assembly in which levers are coupled in the form of a whippletree. 
         [0065]    (5) The arm side coupling portion  31  is symmetric in shape in the widthwise direction with the shape sustaining wall  33  located in the center. That is, the shape sustaining wall  33  is arranged at the middle of the arm side coupling portion  31  in the widthwise direction. The shaft support recesses  32  (support shafts  43 ) thus have the same axial length, and the length of each support shaft  43  is easily obtained. This limits separation of the support shafts  43  in the axial direction from the shaft support recesses  32 . 
         [0066]    (6) The shape sustaining wall  33  is formed to extend to the distal end of the arm side coupling portion  31 . This further increases the strength of the shape sustaining wall  33 . As a result, the rigidity is further increased to limit opening of the attachment-separation port  34 . 
         [0067]    The embodiment described above may be modified in the following manner. 
         [0068]    In the embodiment described above, the arm side coupling portion  31  includes the shaft support recesses  32 , and the blade side coupling portion  41  includes the support shafts  43 . Instead, the arm side coupling portion  31  may include the support shafts, and the blade side coupling portion  41  may include the shaft support recesses. 
         [0069]    For example, in the structure shown in  FIGS. 6 and 7 , the blade side coupling portion  41  is thinner than the rubber holding portion  44  in the widthwise direction and projects toward the upper side (non-wiping surface side) from the upper cover  45  of the rubber holding portion  44 . Shaft support recesses  51  depressed toward the inner side in the widthwise direction are formed in the two widthwise side surfaces of the blade side coupling portion  41 . A shape sustaining wall  52  is formed between the shaft support recesses  51 . The blade side coupling portion  41  is symmetric in shape in the widthwise direction with the shape sustaining wall  52  located in the center. The shaft support recesses  51  in the two widthwise sides of the shape sustaining wall  52  are identical in shape. 
         [0070]    As shown in  FIG. 7 , the shaft support recesses  51 , which are formed to be arcuate, are coaxial and have the same diameter. The shaft support recesses  51  pivotally support the support shaft  62  of the blade side coupling portion  41 . The axis of each shaft support recess  51  is set to be parallel to the widthwise direction of the wiper blade  12 . A portion peripheral to each shaft support recess  51  defines an attachment-separation port  53 , which opens toward the blade basal side and is used to attach and separate the support shafts  62  to and from the shaft support recesses  51 . 
         [0071]    The shape sustaining wall  52 , which is formed between the two shaft support recesses  51  and the attachment-separation port  53  in the widthwise direction, extends along the heightwise direction (direction perpendicular to the wiping surface G) of the wiper blade  12  to integrally connect an upper wall  54  and a lower wall  55  forming the shaft support recesses  51  and the attachment-separation port  53 . The shape sustaining wall  52  prevents the upper wall  54  and the lower wall  55  from moving away from each other. That is, the shape sustaining wall  52  functions to couple the upper wall  54  and the lower wall  55  to each other and sustain the shape of the attachment-separation port  53  in the shaft support recesses  51  so that the attachment-separation port  53  does not open. 
         [0072]    The arm side coupling portion  31  includes two side walls  61 , which face each other in the widthwise direction (direction of pivot axis), and two support shafts  62 , which are coaxial and project from the inner surfaces of the side walls  61 . The side walls  61  are arranged on the two widthwise sides of the blade side coupling portion  41 , and are formed so that the outer surfaces of the side walls  61  are flush with the widthwise side surfaces of the holder member  13 . The space between the side walls  61  opens toward the upper side (non-wiping surface side) to allow the blade side coupling portion  41  to be coupled. 
         [0073]    In the same manner as the support shaft  43  in the embodiment described above, the support shafts  62  are D-shaped and symmetric to each other. Further, each support shaft  62  includes an arcuate portion  62   a , which has a diameter corresponding to the inner diameter of the shaft support recess  51 , and a small diameter portion  62   b , which has a smaller diameter than the arcuate portion  62   a . In the same manner as the embodiment described above, the wiper blade  12  and the wiper arm  11  are relatively pivoted to a position where the small diameter portion  62   b  of the support shaft  62  corresponds to the attachment-separation port  53  to allow for attachment and separation of the support shafts  62  to and from the shaft support recesses  51  (see  FIG. 9 ). The attachment and separation of the support shaft  62  to and from the shaft support recess  51  are disabled by relatively pivoting the wiper blade  12  about the support shaft  62  from the attachable-separable region, where the attachment-separation port  53  corresponds to the small diameter portion  62   b  of the support shaft  62 , to the wiper usage position shown in  FIG. 7 , and positioning the wiper blade  12  in the non-attachable-separable region, where the attachment-separation port  53  does not correspond to the small diameter portion  62   b.    
         [0074]    Such a structure has substantially the same operations and effects (advantages) as the embodiment described above. 
         [0075]    More specifically, as shown in  FIG. 7 , at the wiper usage position where the wiper arm  11  and the wiper blade  12  are substantially parallel to each other, the small diameter portions  62   b  of the support shafts  62  are not in correspondence with the attachment-separation port  53  of the shaft support recesses  51 . This disables the attachment and separation of the support shafts  62  and the shaft support recesses  51 . Referring to  FIG. 8 , engagement of the arm side engagement portion  37  and the blade side engagement portion  47  limits pivoting of the wiper blade  12  in the non-attachable-separable region. Referring to  FIG. 9 , relative pivoting of the wiper blade  12  to the attachable-separable region, where the attachment-separation port  53  corresponds to the small diameter portion  62   b  of the support shaft  62 , disengages the arm side engagement portion  37  from the blade side engagement portion  47 , which have been in elastic engagement, and enables attachment and separation of the support shafts  62  and the shaft support recesses  51 . 
         [0076]    Further, in the same manner as the embodiment described above, in a structure such as that shown in  FIGS. 6 and 7 , the support shafts  62  and the coupling hole that pivotally couple the wiper blade  12  and the wiper arm  11  are axially divided. Thus, the coupling hole that supports the support shaft  62  does not need to be a through hole. The shape sustaining wall  52  located between the divided coupling holes (two shaft support recesses  51 ) couple the upper wall  54  and the lower wall  55  to each other so that the attachment-separation port  53  of the shaft support recesses  51  does not open and to sustain the shape of the attachment-separation port  53 . Thus, even when the coupling portions  31  and  41  are reduced in size in the heightwise direction (direction perpendicular to the wiping surface G), the attachment-separation port  53  of the shaft support recess  51  does not easily open. 
         [0077]    The structures of the arm side engagement portion  37  and the blade side engagement portion  47  are not limited to the structures of the embodiment described above. For example, as shown in  FIG. 10 , the arm side engagement portion may be an engagement recess  71  in the lower surface of the arm side coupling portion  31  (lower surface of the lower wall  36 ), and the blade side engagement portion may be an engagement projection  72  that projects toward the upper side from the upper cover  45  of the rubber holding portion  44  and is engageable with the engagement recess  71 . 
         [0078]    In the embodiment described above, the shape sustaining wall  33  is formed to completely separate the shaft support recesses  32 . Instead, for example, the shaft support recesses  32  may be in partial communication through a through-hole or a slit that extends through the shape sustaining wall  33  in the direction of the pivot axis. 
         [0079]    In the embodiment described above, the blade side engagement portion  47  and the arm side engagement portion  37  are arranged toward the basal side of the wiper arm  11  from the support shafts  43  and the shaft support recesses  32 , but may be arranged toward the distal side of the wiper arm  11  from the support shafts  43  and the shaft support recesses  32 . The blade side engagement portion  47  and the arm side engagement portion  37  may be omitted from the embodiment described above. 
         [0080]    In the embodiment described above, the shape sustaining wall  33  is arranged at the middle of the arm side coupling portion  31  in the widthwise direction. Instead, for example, the shape sustaining wall  33  may be formed at a position deviated from the middle in the widthwise direction of the arm side coupling portion  31 . 
         [0081]    In the embodiment described above, the attachment-separation port  34  of the shaft support recess  32  is formed to open toward the distal side of the wiper arm  11 . Instead, for example, the attachment-separation port  34  may be formed to open toward the wiping surface side (lower side) of the wiper arm  11 . 
         [0082]    The shape of the support shafts  43  is not limited to the shape of the embodiment described above. The small diameter portion  43   b  does not need to be planar as long as the attachable-separable region and the non-attachable-separable region of the wiper blade  12  may be formed. 
         [0083]    In the embodiment described above, the rubber holding portion  44  of the holder member  13  surrounds and holds the backing  14  and the head portion  21  of the blade rubber  15 . Instead, for example, the rubber holding portion  44  may directly hold only the backing  14  and indirectly hold the blade rubber  15  through the backing  14 . 
         [0084]    In the embodiment described above, the blade rubber  15  and the arm are coupled with the same holder member  13 . Instead, the blade side coupling portion and the rubber holding portion may be arranged in a lever assembly in which levers are coupled in the form of a whippletree. 
         [0085]    In the embodiment described above, the present invention is embodied in the vehicle wiper  10  that wipes the surface of the rear window of the vehicle. Instead, for example, the present invention may be embodied in a vehicle wiper that wipes the surface of the windshield of the vehicle. 
         [0086]    Referring to  FIGS. 11 and 12 , a lateral vibration suppressing structure that suppresses lateral vibration (vibration in the widthwise direction of the wiper) of the wiper blade  12  may be arranged in the wiper of the embodiment.  FIGS. 11 and 12  show an example of a structure (same type of structure as the example of  FIGS. 6 and 7 ) in which the blade side coupling portion  41  includes the shaft support recesses  51 . Same reference numerals are given to components that are similar to those in the example shown in  FIGS. 6 and 7 . 
         [0087]    As shown in  FIGS. 11 and 12 , the blade side coupling portion  41  includes an extending portion  41   a  that extends toward the blade basal side. An engagement groove  81  is formed in the two widthwise side surfaces of the extending portion  41   a . Each engagement groove  81  opens at the lower surface (end face on the wiping surface side) of the extending portion  41   a . The attachment-separation port  53  of the shaft support recess  51  extends diagonally upward from the shaft support recess  51  toward the blade basal side and opens in the upper surface (end face on the non-wiping surface side) of the blade side coupling portion  41 . 
         [0088]    The inner side surface of each side wall  61  of the arm side coupling portion  31  (wiper arm  11 ) includes an engagement protrusion  63  that projects in the widthwise direction of the wiper. The engagement protrusion  63  is movable in the pivot direction about the shaft support recesses  51  in the engagement groove  81  of the blade side coupling portion  41 . 
         [0089]    When the wiper blade  12  is located in the non-attachable-separable region where the attachment and separation of the shaft support recesses  51  and the support shafts  62  is disabled, the engagement protrusion  63  engages the upper end  81   a  (end on the non-wiping surface side) of the engagement groove  81  in the pivot direction. The engagement of the engagement protrusion  63  and the upper end  81   a  of the engagement groove  81  limits the pivoting of the wiper blade  12  in the non-attachable-separable region. Disengagement of the engagement protrusion  63  and the upper end  81   a  of the engagement groove  81  and relative pivoting of the wiper blade  12  to the attachable-separable region where the attachment-separation port  53  corresponds to the small diameter portion  62   b  of the support shaft  62  enable the attachment and separation of the support shaft  62  and the shaft support recess  51   
         [0090]    The wiper arm  11  includes a load receiving unit  64  that extends from the upper wall  11   c  toward the wiping surface (lower side in  FIG. 11 ). The load receiving unit  64  is formed at the middle of the wiper arm  11  in the widthwise direction. The load receiving unit  64  is tetragonal in shape and elongated in the longitudinal direction of the wiper as viewed from the rear side (wiping surface side) of the wiper arm  11 . 
         [0091]    The load receiving unit  64  is inserted into an insertion hole  82 , which extends through the extending portion  41   a  of the blade side coupling portion  41 . The insertion hole  82  is located toward the basal side of the wiper arm (basal side in the longitudinal direction of the wiper arm  11 ) from the shaft support recesses  51 . The insertion hole  82  is formed to be slightly longer than the load receiving unit  64  in the longitudinal direction of the wiper. Thus, a gap is formed with the insertion hole  82  in the two longitudinal sides of the load receiving unit  64  with the load receiving unit  64  inserted in the insertion hole  82 . In the widthwise direction of the wiper, the load receiving unit  64  and the peripheral wall of the insertion hole  82  are in contact with each other or arranged facing each other with an extremely small gap formed in between (gap narrower than the gap in the longitudinal direction of the wiper). The load receiving unit  64  and the insertion hole  82  are formed so as not to inhibit the relative pivoting of the wiper arm  11  and the holder member  13  about the support shafts  62 . 
         [0092]    In such a structure, when load in the widthwise direction of the wiper is applied to the wiper blade  12  (e.g., when the wiper is driven with the blade rubber  15  frozen onto the wiping surface G), the load is received by the load receiving unit  64  through the blade side coupling portion  41 . This limits separation of the support shafts  62  from the shaft support recesses  51  that would occur when the distance is increased in the widthwise direction between the side walls  61  of the wiper arm  11 . As a result, separation of the wiper blade  12  from the wiper arm  11  may be limited. 
         [0093]    In the example described above, the load receiving unit  64  of the arm side coupling portion  31  is inserted into the insertion hole  82  of the blade side coupling portion  41 . However, the recess-projection relationship is not limited in such a manner. For example, the projection of a blade side coupling portion may be inserted into the recess of an arm side coupling portion. 
         [0094]    In the example described above, the lateral vibration suppressing structure (the load receiving unit  64  and the insertion hole  82 ) is arranged on the wiper in which the blade side coupling portion  41  includes the shaft support recess  51 . Instead, the lateral vibration suppressing structure may be arranged on the wiper in which the arm side coupling portion  31  includes the shaft support recess like in the embodiment described above. 
         [0095]    In the embodiment described above, pivoting of the wiper blade  12  relative to the wiper arm  11  corresponds to relative rotation of the wiper blade  12  and the wiper arm  11 . However, relative rotation is not limited in such a manner. More specifically, the wiper arm  11  may rotate relative to the wiper blade  12 . In this case, an attachable-separable region and a non-attachable-separable region are set as angular regions of the wiper arm  11  relative to the wiper blade  12 . When the wiper arm  11  is pivoted and the wiper arm  11  is in the non-attachable-separable region, the attachment and separation of the support shaft and the shaft support recess are disabled.