Abstract:
The prevent invention discloses a boneless wiper blade, which mainly consists of a pivot socket, two end ferrules, spring steel sheet and rubber strip, wherein the spring steel sheet is used to support and fix the rubber strip, and the pivot socket, on which the connecting adaptors are installed to connect with wiper arms, is mounted on the center of the spring steel sheet and the rubber strip, with end ferrules mounted at both ends of them. The upper part of the wind-pressure sheathes featuring specially curved surface is designed to prevent the wiper blade from lifting off from the surface of the windshield at highway speeds. The said spring steel sheet is so parabolically designed that the rubber strip can firmly and closely contact the various windshield glasses. Both connecting structures between the connecting adaptor and the pivot socket, and the pivot socket and the spring steel sheet and rubber strip are removable, it is same with the connecting structure between end ferrule and spring steel sheet and rubber strip. In this way, it is easy to assemble, dismount and replace them, and even facilitate use of them. The wiper blade has strong compatibility in that the pivot socket can be mounted with various kinds of connecting adaptors to be compatible with multiple wiper arm configurations.

Description:
FIELD OF THE INVENTION  
       [0001]    This invention relates to a wiper blade used for the windshield glass, and more particularly, to a boneless wiper blade. 
       DESCRIPTION OF THE RELATED ART  
       [0002]    Windshield wiper blades for cars and vehicles are mounted to remove rainwater or impurity to prevent them from obstructing drivers&#39; sight at the time of driving. Although they are very small relative to a car or vehicle, they play vital role in them. 
         [0003]    Generally, the wiper blade is divided into bone wiper blade and boneless wiper blade. As to bone wiper blade, the wiper blade structure is connected with wiper arms through a framework. However, the wiper blade structure is stressed by the framework at multiple points, the rubber strip for the wiper blade cannot always firmly and closely contact windshield glass, resulting in poorer performance of the wiper blade. As to boneless wiper blade, it connect with the wiper arm through the connecting device, leaving no part but the connecting device at the middle portion of the wiper blade structure stressed, which results in more firm and close contacting of the rubber strip with windshield glass, and better performance of the wiper blade accordingly. 
         [0004]    The present invention relates to a boneless wiper blade. For information about the typical structure for the boneless wiper blade, it is advisable to refer to the Chinese utility model patent CN200992193Y (publication number) along with  FIGS. 1 and 2 . As shown in the figures, the said wiper blade generally consists of Rubber Strip  1 ′, Spring Steel Sheet  2 ′, End Ferrule  3 ′, end buckle  4 ′ and connecting device  5 ′, wherein, the said rubber strip  1 ′ is clamped and fixed by the spring steel sheet  2 ′; and then the groove  31 ′ at the inner side of the end ferrule  3 ′ clamps the both sides of the spring steel sheet  2 ′; middle portion of the rubber strip  1 ′ and the spring steel sheet  2 ′ is fixed by the connecting device  5 ′, and then the rubber strip  1 ′, spring steel sheet  2 ′ and both ends of the end ferrule  3 ′ are fixed by the end buckle  4 ′. 
         [0005]    Drawbacks of present boneless wipe blade structures are as follows, 
         [0006]    Firstly, drawbacks of the end ferrule: 
         [0007]    As shown in the  FIG. 2 , the exterior side of the said end ferrule  3 ′ has a upwardly-elevating crest section  32 ′ whose both sides are formed into a slope. Presently, the crest section  32 ′ of the end ferrule  3 ′ is sometimes set symmetrically, and sometimes set asymmetrically; and the slope at both sides of the crest section  32 ′ features varies shapes. Whatever shape of exterior profile of the present end ferrule is taken, its purpose is to deflect air current to smoothly flow along the slope at both sides of the crest section  32 ′ so as to suppress shaking of the wiper blade while at highway speeds. 
         [0008]    As the structure of the crest section of the exterior side of the present end ferrule and deflecting slope is run through the whole end ferrule and even the exterior profile of the end buckle at both ends of the wiper blade for securing purpose also follows the shape of the end ferrule, therefore, the end ferrule for the present boneless wiper blade only addresses the problem of preventing the wiper blade from pulling by deflecting air current. However, the wiper blade would be lift off from the windshield glass or lift off from its middle portion at the highway speeds. As a result, the rubber strip for the wiper blade would not firmly and closely contact the windshield glass fully or partially, resulting in poorer performance of the wiper blade. 
         [0009]    Secondly, drawbacks of the spring steel sheet: 
         [0010]    The spring steel sheet providing support to the rubber strip in the present boneless wiper blade is shown in  FIG. 2 , which includes two pieces of spring steel sheet  2 ′ clamping, supporting and fixing rubber strip  1 ′. It is also okay to place one piece of spring steel sheet over the rubber strip, and connect the spring steel sheet with the rubber strip by auxiliary parts. Whatever two pieces or one piece of spring steel sheet are (is) taken, their (its) vertical shape are (is) symmetrically arched, which can generate spring force. When the spring force is applied to the middle portion of the spring steel sheet, the latter will be pressed against the windshield glass. Nevertheless, when the whole arc shape is flat, no balanced pressing force will be generated to press against the glass, which will result in poorer performance of the wiper blade. To address the problem, two solutions are delivered for the current product. The one solution is shown in  FIG. 3A  and  FIG. 3B , wherein the said spring steel sheet  2 ′ is designed in such way that the middle portion is thicker or wider than both ends. Through such design and proper proportion of arc line to height, rating pressing force is generated. When the spring force is applied to the middle portion of the spring steel sheet, the sheet will generate more balanced pressing force, resulting in improving wiper blade performance. However, the design has its own drawback: it is difficult to assure consistency of products when mass production in that it is impossible to keep under control the rating pressing force generated by such design and proper proportion of arc line to height. The other solution is design the spring steel sheet into multiple-section arc with various curvatures. In this way, when the spring steel sheet is pressed flat at its middle portion, pressing force will be generated on the whole spring steel sheet, resulting in better performance of the wiper blade. Nevertheless, the design also bears its drawback: as shown in  FIG. 3C , when the whole cambered surface is pressed flat, pressing force is generated on the whole spring steel sheet  2 ′. However, multiple cambered surfaces are tangent to each other, resulting in point of intersection a formed by different arc line contacting the glass, and elevation in other areas. Microscopically, wave shape is formed when the spring steel sheet is pressed flat (as shown in  FIG. 3D ). It is therefore impossible to generate balanced pressing force on the whole spring steel sheet  2 ′, which reduces the performance of the rubber strip. 
         [0011]    Thirdly, drawbacks of the connecting device: 
         [0012]    For a boneless wiper blade, its principal part is connected with the wipe arm mounted on the windshield glass through the connecting device. Generally speaking, structure setting of the connecting device is subject to structure of the wiper arm. Whichever connecting device is taken, it typically consists of a pivot socket which mounted on the middle portion of the principal part of the wiper blade, and connecting adaptors, which are mounted on the pivot socket. They are coupled to connect with the wiper arm. Some wiper blades are provided with a outer cover outside of the connecting adaptors to house the internal structure for appearance purpose. At present, the connecting device is assembled in fixed way, where the pivot socket is welded or riveted on the principal part of the wiper blade, and the connecting adaptors are riveted on the pivot socket. For further information, see also the Chinese utility model patent No. CN201073958Y publicized on Jun. 18, 2008. For some connecting devices with a outer cover, their outer covers are often riveted to the connecting adaptors. 
         [0013]    Given the existing fixed-type connecting device for the wiper blade, the whole wiper blade will have to be rejected when the principal part of the wiper blade or part of the connecting device is damaged, resulting in more waste. Basing on the above reason, this inventor discovers that the connecting adaptors, also the connecting part between the connecting device and wiper arm, are vulnerable to damage through long-term research. Therefore, rejection of whole wiper blade resulting from merely damage of connecting adaptors of the connecting device leads to a greater amount of waste. Similarly, there exists a problem in removing connection between the said pivot socket and principal part of the wiper blade. 
         [0014]    Fourthly, drawback of the structure connecting end buckle and end ferrule and spring steal sheet: 
         [0015]    The end buckle of existing wiper blades are generally connected with end ferrule and spring steel sheet in welded or riveted way. Similarly, the connection cannot be removed as abovementioned, and no damaged but all parts are replaced. 
         [0016]    Fifthly, poor compatibility of existing wiper blade: 
         [0017]    As each brand and model car is compatible with various structures of wiper arms, wiper blade with corresponding connecting device must be equipped with. What&#39;s more, the connecting device is connected in a fixed way, it leads to poorer compatibility of such wiper blade. 
       SUMMARY OF THE INVENTION  
       [0018]    A major technical problem intended to be addressed by this invention is to deliver a boneless wiper blade, whose end ferrule can prevent wiper blade life off from the windshield glass at highway speeds. 
         [0019]    Another technical problem intended to be addressed by this invention is to deliver a boneless wiper blade, whose spring steel sheet can facilitate closer contact between the rubber strip and windshield glass with various curved surface curvature. 
         [0020]    An additional technical problem intended to be addressed by this invention is to deliver a boneless wiper blade, whose connecting adaptors and pivot socket, and pivot socket and spring steel sheet and rubber strip are removably connected, leading to easy assembly, removing and replacement, and easy to use as well as more compatibility of the wiper blade with multiple wiper arm structures. 
         [0021]    An additional technical problem intended to be addressed by this invention is to deliver a boneless wiper blade, whose end ferrule is removably connected with spring steel sheet and rubber strip instead of connecting by end buckle, leading to easy assembly, removing and replacement, and even facilitate its use. 
         [0022]    Intending to address the above-mentioned technical problems, this invention presents solutions as follows, 
         [0023]    A boneless wiper blade comprising of a pivot socket, two end ferrules, spring steel sheet and rubber strip, wherein the spring steel sheet is used to support and fix the rubber strip, and the pivot socket, on which the connecting adaptor is installed to connect with wiper arms, is installed on the center of the spring steel sheet and the rubber strip, with two end ferrules mounted at both ends of the spring steel sheet and rubber strip; the crest section of the said end ferrules is so eccentrically set that longer side of the crest section forms a inwardly curved surface; vertically, the crest section becomes lower outwardly, and the curved surface becomes higher exteriorly, resulting in integrating the crest section and inwardly-curved surface as a smooth curve. 
         [0024]    Externally curved surface, whose cross section is upwardly convex arc-shaped, which vertically becomes higher inwardly, and finally integrates with the crest section and the curved surface, is provided at the outer end of the said end ferrules. 
         [0025]    The said spring steel sheet is parabolic shape with gradual change curvature, and has no arch section joint; with rating elastic force for springs resulting from restricting height and curvature ratio of chord width of parabola, and by flatting the parabola by applying pressure to the middle part of the parabola, the spring elastic force for the whole spring steel sheet would be smooth, balanced and rated pressure value owning to the gradual change curvature, and automatically adjustable gradual change curvature is consistent with radians of various glass curved surface. 
         [0026]    One piece of the said spring steel sheet is placed on the rubber strip which features 1st groove and 2nd groove longitudinally at both ends; two spacers are mounted into the 1st groove, and barbs of several clips are threaded through square holes, and fitted into the 2nd groove to assemble the spring steel sheet, rubber strip and spacers together. 
         [0027]    The said end ferrule has inwardly kinked grooves at its lower part to fit into both ends of the spring steel sheet; the grooves have sticking points at its external end, which fits into the gaps at the both sides of both ends of the spring steel sheet; the end ferrule has downwardly extended higher side at its external end. 
         [0028]    The said pivot socket has two walls, between which inner groove is formed, and has column; the pivot socket has a slot and slot points at its lower part, and the slot fits into the both sides of middle part of the spring steel sheet; the spring steel sheet has a slot at its middle part to fit into the slot point at the lower part of the pivot socket. 
         [0029]    The said pivot socket can be removably connected to the 1st connecting adaptor, wherein a groove with downward opening is provided at its lower part to match the column of the pivot socket; a square hole is provided at the back end within a notch which is formed within the 1st connecting adaptor, and a round hole is provided at the upper wall of the square hole to match the flat-type wiper arm; a gap is provided nearly at the upper part of the 1st connecting adaptor, and a standoff is provided at a connecting adaptor cap which is provided at the front end pivot joint, to match the gap, and also a baffle sheet is provided at the inner side of the cap to fix the hook-type wiper arm; a slope is provided at the front of the square hole in the 1st connecting adaptor, and a wedge is provided at the front of the groove in the 1st connecting adaptor. A cover is provided over the pivot socket, which is, in turn, covered by a square hole provided at the middle of the cover, and both ends of the cover is formed into curved surface similar to that of the inside end of the end ferrule to cover the end of the inside of the end ferrule; the hook section is provided at the lower part of the cover to hook the lower part of the pivot socket and end ferrules. 
         [0030]    The said pivot socket is removably connected with the 2nd connecting adaptor thereof, which is a hollow body with the lower part open; a groove with downward opening is provided at the inside of the connecting adaptor to match the column of the pivot socket, and round holes are provided at the side wall of the connecting adaptor, and a resilient sheet is provided above the round hole within the connecting adaptor; a hole is provided at the supporting wall of the pivot socket opposite to the round hole of the connecting adaptor; two troughs are provided at the top of the 2nd connecting adaptor to match two supporting walls of the pivot socket; a groove is provided at the top of the 2nd connecting adaptor to match the wiper arm with a hook; a concave is provided at the top of two supporting walls of the pivot socket to match the groove of the 2nd connecting adaptor. A cover is provided over the pivot socket, which is, in turn, covered by a square hole provided at the middle of the cover, and both ends of the cover is formed into curved surface similar to that of the inside end of the end ferrule to cover the end of the inside of the end ferrule; the hook section is provided at the lower part of the cover to hook the lower part of the pivot socket and end ferrules. 
         [0031]    The said pivot socket is removably connected with the 3rd connecting adaptor thereof, which is a hollow body with the lower part open; a groove with downward opening is provided at the inside of the connecting adaptor to match the column of the pivot socket, and a resilient boss is provided at the top wall of the connecting adaptor to match the hole in the wiper arm; two troughs are provided at the top of the 3rd connecting adaptor to match the two supporting walls of the pivot socket. A cover is provided over the pivot socket, which is, in turn, covered by a square hole provided at the middle of the cover, and both ends of the cover is formed into curved surface similar to that of the inside end of the end ferrule to cover the end of the inside of the end ferrule; the hook section is provided at the lower part of the cover to hook the lower part of the pivot socket and end ferrules. 
         [0032]    The said pivot socket is removably connected with the 4th connecting adaptor thereof, which is a hollow body with the lower part open; a groove with downward opening is provided at the inside of the connecting adaptor to match the column of the pivot socket; a slot is provided at the front of the top wall of the 4th connecting adaptor to match the block at the front of the wiper arm, and the front of the slot serves as blocking wall to match the front-end surface of the wiper arm; resilient clamp stands are provided at the both sides of the 4th connecting adaptor to match the clamping surface of the wiper arm; two troughs are provided at the top of the 4th connecting adaptor to match the two supporting walls of the pivot socket. A cover is provided over the pivot socket, which is, in turn, covered by a square hole provided at the middle of the cover, and both ends of the cover is formed into curved surface similar to that of the inside end of the end ferrule to cover the end of the inside of the end ferrule; the hook section is provided at the lower part of the cover to hook the lower part of the pivot socket and end ferrules. 
         [0033]    The said pivot socket is removably connected with the 5th connecting adaptor thereof, which is a hollow body with the lower part open; a groove with downward opening is provided at the inside of the connecting adaptor to match the column of the pivot socket; a slot is provided at the front of the top wall of the 5th connecting adaptor to match the block at the front of the wiper arm, and the front of the slot serves as blocking wall to match the front-end surface of the wiper arm; resilient clamp stands are provided at the both sides of the 5th connecting adaptor to match the clamping surface of the wiper arm; resilient clamp stands are provided at the top wall of the connecting adaptor to match the clamping hole at the top of the wiper arm; two troughs are provided at the top of the connecting adaptor to match the two supporting walls of the pivot socket. A cover is provided over the pivot socket, which is, in turn, covered by a square hole provided at the middle of the cover, and both ends of the cover is formed into curved surface similar to that of the inside end of the end ferrule to cover the end of the inside of the end ferrule; the hook section is provided at the lower part of the cover to hook the lower part of the pivot socket and end ferrules. 
         [0034]    The said pivot socket is removably connected with the 6th connecting adaptor thereof, which is a block body, and a groove with downward opening is provided within the connecting adaptor to match the column of the pivot socket, and slot is formed at the back side of the groove to connect the latter; the slot is to match the clamp block at the front of the wiper arm, and boss is formed at the front of the slot to match the front-end clamp block of the wiper arm; a resilient clamp stands are provided at both sides of the 6th connecting adaptor to match the clamping surface of the wiper arm; additionally, two side surfaces of the foresaid 6th connecting adaptor forms into stepped surfaces, viz, the bigger lower stepped surface matching the internal notch of the pivot socket, and the smaller upper stepped surface matching U-shape wiper arm; also the blocking wall is formed at the front of the 6th connecting adaptor to match the front-end surface of the wiper arm. A cover is provided over the pivot socket, which is, in turn, covered by a square hole provided at the middle of the cover, and both ends of the cover is formed into curved surface similar to that of the inside end of the end ferrule to cover the end of the inside of the end ferrule; the hook section is provided at the lower part of the cover to hook the lower part of the pivot socket and end ferrules. 
         [0035]    With the above-mentioned solutions taken, this invention will at least bring about following benefits: 
         [0036]    1. As the crest section and curved surface of the said end ferrule is specifically designed to become outwardly lower and higher respectively, and couple with externally curved surface with special structure, it leaves wind resistance to be concentrated on the middle portion of the wiper blade structure, and higher outside end of curved surface is also helpful to stop air current from flowing out of the outside end of the end ferrule. In this way, it makes air current hard to flow out of both ends of the wiper blade but to be gathered within the internal end of curved surface, assisting in pressing down the wiper blade, and facilitating close contact between the rubber strip and glass, which as a result, avoids wiper lift off from the windshield glass owning to wind resistance against the windshield at highway speeds. 
         [0037]    2. Inward concave curvature for curved surface of the said end ferrule enables wind resistance to offset blowing wind force, resulting in effect of balanced wiping. 
         [0038]    3. The said spring steel sheet is of symmetrical parabola. As parabola curvature is gradually changed, and there is no joint generated by arch section, when the spring steel sheet is pressed flat at its middle portion, pressing force will be generated on the whole spring steel sheet, resulting in better performance of the wiper blade. After the parabola is pressed flat by applying force to its middle portion, smooth and balanced pressing force is generated on the whole spring steel sheet, enabling the spring steel sheet curvature to be automatically adjusted for consistency with curvature for a variety of glass curved surface, and better performance of wiping. Additionally, rating pressing force can be generated by restricting curvature ratio of height to width of the parabola, and make pressed rubber strip gain the rating pressing value, which, in turn, delivers good performance of wiping. 
         [0039]    4. The connecting structures between the pivot socket and spring steel sheet, and pivot socket and a variety of connecting adaptors can be removably connected without being welded or riveted, which not only facilitates use, but also avoid waste in that only damaged parts need replacing. 
         [0040]    5. This invention needs only one pivot socket structure, which facilitates assembly with multiple connecting adaptor structures for compatibility with multiple wiper arm models or structures. For users, it is possible to normalize products only by selecting a corresponding connecting adaptor to facilitate compatibility of one wiper blaze structure with multiple models or types of wiper arms. 
         [0041]    6. Actually, the sticking point within the groove outside the said end ferrule and high edge at the outside end, which corresponds to the end buckle of existing products, enable to simplify structure as well as fix the both ends of the spring steel sheet without welding or riveting them in a bid to prevent the rubber strip and spacers for the rubber strip from falling off. As a result, it is convenient to assemble, remove and replace. The curved surface outside of the end ferrule also plays roles to enhance the appearance. 
         [0042]    7. The curved surface set for both ends of the cover for the said pivot socket, which is same with that of the end ferrule, can cover inner end face of the end ferrule, enabling to protect the end ferrule as well as to prevent impurity from entering into the end ferrule. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0043]      FIG. 1  is a perspective view of one typically existing boneless wiper blaze; 
           [0044]      FIG. 2  is a sectional view of the end ferrule part in  FIG. 1 ; 
           [0045]      FIG. 3A  is a side view of one spring steel sheet structure of one boneless wiper blaze; 
           [0046]      FIG. 3B  is a top view of  FIG. 3A ; 
           [0047]      FIG. 3C  is a schematic drawing showing another flatten spring steel sheet structure of one boneless wiper blaze; 
           [0048]      FIG. 3D  is a schematic drawing showing Micro magnified position A in  FIG. 3C ; 
           [0049]      FIG. 4  is a perspective exploded view of this invention without being provided with the connecting adaptors; 
           [0050]      FIG. 5  is a perspective bottom-to-top exploded view of this invention without being provided with the connecting adaptors; 
           [0051]      FIG. 6  is a perspective combination view of this invention without being provided with the connecting adaptors; 
           [0052]      FIG. 7  is a perspective view of the said end ferrule hereof; 
           [0053]      FIG. 7A  is a sectional view A-A of  FIG. 7 ; 
           [0054]      FIG. 7B  is a sectional view B-B of  FIG. 7 ; 
           [0055]      FIG. 7C  is a sectional view C-C of  FIG. 7 ; 
           [0056]      FIG. 7D  is a sectional view D-D of  FIG. 7 ; 
           [0057]      FIG. 7E  is a sectional view E-E of  FIG. 7 ; 
           [0058]      FIG. 8  is a perspective view of the said end ferrule of the present invention as seen from underneath; 
           [0059]      FIG. 8A  is a partial enlargement view of  FIG. 8 ; 
           [0060]      FIG. 9A  is a schematic drawing showing the natural state of the spring steel sheet of the present invention; 
           [0061]      FIG. 9B  is a schematic drawing showing the state of the spring steel sheet of the present invention at its midpoint under press; 
           [0062]      FIG. 9C  is a schematic drawing showing the state of the spring steel sheet of the present invention in use; 
           [0063]      FIG. 10  is a perspective view of the clutch of the present invention; 
           [0064]      FIG. 11  is a partial perspective view of the rubber strip of the present invention; 
           [0065]      FIG. 12  is a perspective view showing combination of the 1st connecting adaptor and other parts of the wiper blade of the present invention; 
           [0066]      FIG. 13  is a perspective schematic drawing showing the 1st connecting adaptor of the present invention; 
           [0067]      FIG. 14  is a perspective schematic drawing showing the cover for the 1st connecting adaptor of the present invention; 
           [0068]      FIG. 15  is a perspective exploded view showing connection of the 1st connecting adaptor with other parts of the wiper blade and hook-type wiper arm of the present invention; 
           [0069]      FIG. 16  is a combination sectional view of  FIG. 15  of the present invention; 
           [0070]      FIG. 17  is a perspective exploded view showing connection of the 1st connecting adaptor with other parts of the wiper blade and flat-type wiper arm of the present invention; 
           [0071]      FIG. 18  is a combination sectional view of  FIG. 17  of the present invention; 
           [0072]      FIG. 19  is a perspective schematic drawing of the 2nd connecting adaptor of the present invention; 
           [0073]      FIG. 20  is a sectional view of the 2nd connecting adaptor of the present invention; 
           [0074]      FIG. 21  is a perspective exploded view of connection of the 2nd connecting adaptor with other parts of the wiper blade and one side bolt-type wiper arm of the present invention; 
           [0075]      FIG. 22  is a perspective combination view of  FIG. 21 ; 
           [0076]      FIG. 22A  is a sectional view A-A of  FIG. 22 ; 
           [0077]      FIG. 23  is a perspective exploded view of connection of the 2nd connecting adaptor with other parts of the wiper blade and another side bolt-type wiper arm of the present invention; 
           [0078]      FIG. 24  is a perspective combination view of  FIG. 23 ; 
           [0079]      FIG. 24A  is a sectional view B-B of  FIG. 24 ; 
           [0080]      FIG. 24B  is a sectional view C-C of  FIG. 24 ; 
           [0081]      FIG. 25  is a perspective schematic drawing of the 3rd connecting adaptor of the present invention; 
           [0082]      FIG. 26  is a sectional view of the 3rd connecting adaptor of the present invention; 
           [0083]      FIG. 27  is a perspective exploded view of connection of the 3rd connecting adaptor with other parts of the wiper blade and one wiper arm of the present invention; 
           [0084]      FIG. 28  is a perspective combination view of  FIG. 27 ; 
           [0085]      FIG. 28A  is a sectional view A-A of  FIG. 28 ; 
           [0086]      FIG. 28B  is a sectional view B-B of  FIG. 28 ; 
           [0087]      FIG. 29  is a perspective schematic drawing of the 4th connecting adaptor of the present invention; 
           [0088]      FIG. 30  is a sectional view of the 4th connecting adaptor of the present invention; 
           [0089]      FIG. 31  is a perspective exploded view of connection of the 4th connecting adaptor with other parts of the wiper blade and one wiper arm of the present invention; 
           [0090]      FIG. 32  is a perspective combination view of  FIG. 31 ; 
           [0091]      FIG. 32A  is a sectional view A-A of  FIG. 32 ; 
           [0092]      FIG. 32B  is a sectional view B-B of  FIG. 32 ; 
           [0093]      FIG. 33  is a perspective schematic drawing of the 5th connecting adaptor of the present invention; 
           [0094]      FIG. 34  is a sectional view of the 5th connecting adaptor of the present invention; 
           [0095]      FIG. 35   a  is a perspective exploded view of connection of the 5th connecting adaptor with other parts of the wiper blade and one wiper arm of the present invention; 
           [0096]      FIG. 36  is a perspective schematic drawing of the 6th connecting adaptor of the present invention; 
           [0097]      FIG. 37  is a perspective exploded view of connection of the 6th connecting adaptor with other parts of the wiper blade and one wiper arm of the present invention; 
           [0098]      FIG. 38  is a perspective combination view of  FIG. 37 ; 
           [0099]      FIG. 38A  is a sectional view C-C of  FIG. 38 ; 
           [0100]      FIG. 38B  is a sectional view D-D of  FIG. 38 . 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0101]    In the following, the present invention will be further amplified by means of drawings and specific embodiment. 
         [0102]    The present invention discloses a boneless wiper blade (as shown in  FIGS. 4 ,  5  and  6 ), which is one preferred embodiment of the present invention. The said wiper blade consists of a pivot socket  10 , two end ferrules  20 , a pivot socket cover  30 , a piece of spring steel sheet  40 , several clutches  50 , a rubber strip  60  and two spacers  70 , along with a connecting device mounted on the pivot socket  10  (provided blow for details), wherein: 
         [0103]    The said pivot socket  10  is provided with two support walls  14 ; inner notch  11  is formed between two support walls  14 ; inner notch  11  is provided with a column  12 ; a hole  13  is provided at the support wall  14 ; a concave  17  is provided at the top, and a slot  15  and slot point  16  are provide at the lower part of the pivot socket  1 . 
         [0104]    As shown in  FIG. 7 , and  FIG. 7A-7E , a inwardly kinked groove  21  is provided at the said end ferrule  20  to firmly match both sides of the undermentioned spring steel sheet  40 ; the end ferrule  20  features a upward elevated and eccentrically-set crest section  22  at its upper part, and the longer side of the crest section forms a inwardly curved surface  23 ; vertically, the said crest section  22  becomes lower outwardly, and the curved surface  23  becomes higher exteriorly, resulting in integrating the crest section  22  and inwardly-curved surface  23  as a smooth curve; 
         [0105]    Externally curved surface  24 , whose cross section is upwardly convex arc-shaped, which vertically becomes higher inwardly, and finally integrates with the crest section  22  and the curved surface  23 , is provided at the outer end of the said end ferrules  20 . 
         [0106]    As shown in  FIG. 8  and  FIG. 8A , the grooves  21  of the end ferrule  20  have sticking points  25  at its external end to facilitate connection of the said end ferrule  20  with the spring steel sheet  40 ; the end ferrule  20  has downwardly extended higher side  26  at its external end. 
         [0107]    Inward concave curvature for curved surface  23  of the said end ferrule  20  enables wind resistance to offset blowing wind force, resulting in effect of balanced wiping. As the crest section  22  and curved surface  23  of the said end ferrule is specifically designed to become outwardly lower and higher respectively, and couple with externally curved surface  24  with special structure, it leaves wind resistance to be concentrated on the middle portion of the wiper blade structure, as indicated by the arrow in  FIG. 6 , higher outside end of curved surface  23  is also helpful to stop air current from flowing out of the outside end of the end ferrule  20 . In this way, it makes air current hard to flow out of both ends of the wiper blade but to be gathered within the internal end of curved surface  23 , assisting in pressing down the wiper blade, and facilitating close contact between the rubber strip and glass, which as a result, avoids wiper lift off from the windshield glass owning to wind resistance against the windshield at highway speeds. 
         [0108]    The said pivot socket cover  30  is provided with a square hole  31  at its middle, its both ends form into a curved surface  32  with same shape with the inner end of the end ferrule  20 , and a hook section  33  is provided at its lower part. 
         [0109]    As shown in  FIG. 9A , the said spring steel sheet  40 , a resilient strip, is in parabolic shape under free state. The spring steel sheet  40  is provided with a slot  41  at its both sides to match the slot point at the lower part of the pivot socket  10 ; the both sides of both ends of the sheet is provided with gap  42  to match the slot point  25  at lower part of the end ferrule  20 ; the spring steel sheet  40  is provided with several square holes  43  at its steel surface. 
         [0110]    Balanced pressing force can be generated as the spring steel sheet  40  of the present invention is designed to be in symmetrical parabolic curve shape (as shown in  FIG. 9A ). The reason is that curvature of the parabolic curve is gradually changed, and there is no arch section joint; with rating elastic force for springs resulting from restricting height and curvature ratio of chord width of parabola, and by flatting the parabola (as shown in  FIG. 9C ) by applying pressure to the middle part of the parabola (as shown in  FIG. 9B ), the spring elastic force for the whole spring steel sheet would be smooth, balanced and rated pressure value owning to the gradual change curvature, and automatically adjustable gradual change curvature is consistent with radians of various glass curved surface, realizing better effect of wiping. 
         [0111]    The said clutch  50  (as shown in  FIG. 10 ) is provided with a barb  51  at its lower part. 
         [0112]    The said rubber strip  60  is a long strip body, with 1st groove  61  and 2nd groove  62  provided at its both vertical sides (as shown in  FIG. 11 ). 
         [0113]    The said spacer  70  is mounted in the 1st groove  61  of the rubber strip  60 . Assembly of this invention may take steps as follows, 
         [0114]    Firstly, two spacers  70  is mounted in the 1st groove  61  at both sides of the rubber strip  60 , and the spring steel sheet  40  is placed on the rubber strip  60 , and barb  51  of the clutch  50  is threaded through the square hole  43  on the spring steel sheet  40 , and then the barb  51  is firmly matched with the 2nd groove. In this way, spring steel sheet  40 , clutch  50 , rubber strip  60  and spacer  70  are so integrated that the rubber strip  60  and spacer  70  would not fall off. 
         [0115]    Secondly, groove  15  of the pivot socket  10  is matched with both sides of the middle portion of the spring steel sheet  40 , and the slot point  16  is aligned with the slot  41  at the middle of the spring steel sheet  40 . In this way, the pivot socket  10  is removably connected at the middle of the spring steel sheet  40 . As there is no need for riveting or welding in the structure, it is convenient to remove or replace damaged parts. 
         [0116]    Thirdly, two end ferrules  20  are mounted at both ends of the pivot socket  10  respectively by matching groove  21  with the both sides of the spring steel sheet  40 , and gap  42  at both ends of the spring steel sheet with slot point  24  of the end ferrule  20  so as to prevent the end ferrule from falling off. The high edge  26  outside of the end ferrule  20  can cover exterior ends of the spring steel sheet  40  and the rubber strip  60 , providing protection for the spring steel sheet  40  and rubber strip  60 . The exterior-end slot point  25  and high edge  26  of the end ferrule  20  play roles corresponding with end buckle of existing products. Unlike end buckle, which is fixed by means of welding or riveting, they are aligned and matched together, so it is convenient to assemble and disassemble. 
         [0117]    Fourthly, the pivot socket  10  is fit into the square hole  31  of the pivot socket cover  30 , and inner end of the end ferrule  20  is covered by curved surface at both ends of the pivot socket cover  30 . The pivot socket  10 , and end ferrule  20  are hooked by the hook section  33  at the lower part of the pivot socket cover  30  at the latter&#39;s lower part. In this way, the pivot socket  10 , end ferrule  20  and pivot socket cover  30  are integrated. Coverage of cover inner end of the end ferrule  20  by the pivot socket cover can not only protect end ferrule  20 , but also prevent impurity from entering into the end ferrule  20 . 
         [0118]    Benefit of the above-mentioned wiper blade structure lies in that the pivot socket  10  can be mounted with multiple connecting adaptor structures for compatibility with various wiper arms. This invention relates to several connecting adaptor structures, which are to be described in the following. The 1st connecting adaptor  80   a  of the present invention is shown in  FIG. 12-14 . 
         [0119]    Notch  84   a  is formed into the said 1st connecting adaptor  804  as shown in  FIG. 13 ). A slot  81   a  with downward opening is provided at the lower part of the 1st connecting adaptor  80   a,  and a hole  82   a  is provided at the front end of the adaptor. Limit arc notch  821   a  is provided at the edge of the hole  82   a.  A gap  83   a  is provided at the front of the upper part of the 1st connecting adaptor, and a wedge  85   a  is provided at the front of the slot  81   a;  a square hole  86   a  is provided at the back end within the groove  84   a;  a circular hole  87   a  is provided at the upper wall of the square hole  86   a;  and a slope  89   a  (as shown in Nomograph  12  or  FIGS. 16 and 18 ) is also provided at the front of the square hole  86   a.  Additionally, a connecting adaptor cover  88   a  (as shown in  FIG. 14 ), which is provided with a jack post  881   a,  bump  882   a,  clamp column  883   a  and block piece  884   a,  is pin jointed with the front end of the 1st connecting adaptor  80   a.  The said jack post  881   a  is pin-jointed with the hole  82   a  on the 1st connecting adaptor  80   a;  the bumps  882   a  are provided at the both ends of the jack post  881   a,  and match up with the above-mentioned limit arc notch  821   a  to limit place of rotation of the connecting adaptor cover  88   a;  the said clamp column  883   a  can be locked in the gap  83   a  on the 1st connecting adaptor  80   a  with a view to cover the front end of the 1st connecting adaptor with the connecting adaptor cover  88   a;  the said block piece  884   a  is provided at the inner side of the connecting adaptor cover  88   a,  and can be elastic enough to fix the aftermentioned hook-type wiper arm  9 A. 
         [0120]    When the said 1st connecting adaptor  80   a  is assembled with the pivot socket  10 , it is fit into the inner groove  11  of the pivot socket  10 , and is fixed by locking the column  12  of the pivot socket  10  into its slot  81   a.  The said 1st connecting adaptor  80   a  may be firmly assembled with the hook-type wiper arm and flat-type wiper arm. 
         [0121]      FIGS. 15 and 16  are schematic drawings showing assembly of the above-mentioned 1st connecting adaptor of the present invention with the hook-type wiper arm  9 A. The said hook-type wiper arm  9 A is an existing structure, with its front end being formed into a hook  91 A. 
         [0122]    When the said 1st connecting adaptor  80   a  is assembled with the wiper arm  9 A, firstly, turn up the cover  88   a  for the 1st connecting adaptor  80   a,  and then mount the hook at the front of the wiper arm  9 A in the slot  84   a  of the 1st connecting adaptor, and then turn down the cover  88   a  after positioning by the wedge  85   a  so as to lock the clamp column  883   a  into the gap  83   a  on the 1st connecting adaptor  80   a.  So the block piece  884   a  will lean against the front end of the wiper arm  9 A to reinforce the latter. 
         [0123]      FIGS. 17 and 18  are structure schematic drawings showing assembly of the above-mentioned 1st connecting adaptor of the present invention with the flat-type wiper arm  9 B, which is provided with a bump  92 B. When the flat-type wiper arm  9 B, which is also an existing structure, is assembled with the 1st connecting adaptor  80   a,  insert the wiper arm  9 B into the square hole  86   a  of the 1st connecting adaptor  80   a  to lock the bump  92 B into the circular hole  87   a  of the 1st connecting adaptor. Along with the circular hole  87   a,  the slope  89   a  within the slot  84   a  of the 1st connecting adaptor which reduces to slightly lift up the front end of the wiper arm  9 B fix the bump  92 B, making the wiper arm  9 B securely connected. 
         [0124]    The 2nd connecting adaptor  80   b  structure of the present invention is shown in  FIGS. 19 and 20 . 
         [0125]    The said 2nd connecting adaptor  80   b,  which is a hollow body with its lower part open, is provided with slot  81   b  with downward opening, and circular hole  82   b  on its side wall, and a resilient sheet  83   b  is provided above the round hole within the connecting adaptor, with its exterior end extending beyond the 2nd connecting adaptor  80   b.  Additionally, two troughs  84   b,  along with a groove  85   b,  is provided at the top surface of the 2nd connecting adaptor, 
         [0126]    As shown in  FIG. 21 , the 2nd connecting adaptor  80   b  is fit into the pivot socket, and positioned by locking the column  12  of the pivot socket  10  into its slot  81   b,  and inserting the trough  84   b  of the 2nd connecting adaptor into the support wall  14  of the pivot socket  10  when the 2nd connecting adaptor is assembled with the pivot socket  10 . Following the assembly, the circular hole  82   b  on the 2nd connecting adaptor is opposite to the through-hole on the pivot socket  10 . The 2nd connecting adaptor  80   b  can be compatible with existing two types of side bolt-type wiper arms. 
         [0127]    FIGS.  21 , 22  and  22 A is a schematic drawing showing assembly of the above-mentioned 2nd connecting adaptor  80   b  with one side bolt-type wiper arm  9 C structure. Pin  91 C, which is provided with inwardly recessed step  92 C, is provided at the front end of the said wiper arm. When assembled, pin  91 C of the wiper arm  9 C is inserted into the circular hole  82   b  of the 2nd connecting adaptor  80   b,  and hole  13  of the pivot socket  10 . Following it, the resilient sheet  83   b  within the 2nd connecting adaptor will be locked within the step  92 C of the pin  91 C, which enable the wiper arm  9 C to connect with the wiper blade. When the wiper arm  9 C is to be disassembled, lift the resilient sheet  83   b  of the 2nd connecting adaptor upward to disconnect it from the step  92 C on the pin  91 C of the wiper arm  9 C. In this way, the pin  91 C of the wiper arm  9 C can be pulled out to separate the wiper arm  9 C from the wiper blade. 
         [0128]      FIGS. 23 ,  24  and  FIGS. 24A and 24B  are schematic drawings showing assembly of the 2nd connecting adaptor  80   b  with another side bolt-type wiper arm  9 D structure. A pin  91 D and hook  92 D are provided at the front end of the said wiper arm  9 D. When assembled, the pin  91 D of the wiper arm  9 D is inserted into the circular hole  82   b  of the 2nd connecting adaptor and the hole  13  on the pivot socket  10 , and the resilient sheet  83   b  within the 2nd connecting adaptor will press against the pin  91 D, assisting in securing the wiper arm  9 D, and the hook  92 D of the wiper arm  9 D is used to hook the another side of the upper part of the 2nd connecting adaptor, and locked into the groove  85   b  of the 2nd connecting adaptor so as to connect the wiper arm  9 D with the wiper blade. When the said wiper arm  9 D is to be disassembled, rotate the wiper arm  9 D around its pin  91 D to lift the wiper blade upward relatively, and separate its upper hook  92 D from the groove  85   b  at the top surface of the 2nd connecting adaptor. In this way, the pin  91 D of the wiper arm can be pulled out to separate the wiper blade from the wiper arm  9 D. 
         [0129]    The 3rd connecting adaptor  80   c  structure of the present invention is shown in  FIGS. 25 and 26 . 
         [0130]    The said 3rd connecting adaptor  80   c  which is a hollow body with its lower part open is provided with slot  81   c  with downward opening, and with resilient boss  82   c  at its top wall. Apart from its own elastic force, the resilient boss  82   c  gains additional elastic force in traditional way where only one side of the boss is connected with the main body. Two troughs  84   c  are provided at the top surface of the 3rd connecting adaptor. 
         [0131]    As shown in  FIG. 27 , the 3rd connecting adaptor  80   c  is fit into the pivot socket  10 , and positioned by locking the column  12  of the pivot socket  10  into its slot  81   c,  and inserting the trough  84   c  of the 3rd connecting adaptor into the support wall of the pivot socket  10  when the 3rd connecting adaptor is assembled with the pivot socket  10 . 
         [0132]    As shown in  FIG. 27 ,  28 , and  FIGS. 28A and 28B , this invention can be compatible with one existing wiper arm via the said 3rd connecting adaptor  80   c.  The said wiper arm  9 E, whose front end cross section is in U shape with its opening downward, is provided with a clamp hole  91 E at its top surface, and barbs  92 E at the bottom of its both side wall. When assembled, the wiper arm  9 E is fit into the 3rd connecting adaptor  80   c  from the one side of the 3rd connecting adaptor where the resilient boss  82   c  is provided, enabling the barb  92 E at the bottom of the wiper arm  9 E to reach the bottom of the 3rd connecting adaptor to prevent the wiper arm  9 E from separating upwardly. When the wiper arm  9 E is fit in place, the resilient boss  82   c  on the 3rd connecting adaptor will be locked into the clamp hole  91 E of the wiper arm  9 E so as to prevent the wiper arm  9 E from separating in forward, backward, left and right directions. In this way, the wiper arm  9 E can be connected with the wiper blade. When the wiper arm  9 E is to be disassembled, the resilient boss  82   c  of the 3rd connecting adaptor is pressed downward to separate it from the clamp hole  91 E of the wiper arm  9 E. At that moment, the wiper arm  9 E can be pulled out to separate it from the wiper blade. 
         [0133]    The 4th connecting adaptor  80   d  structure of this invention is shown in  FIGS. 29 and 30 . 
         [0134]    The said 4rd connecting adaptor  80   d  which is a hollow body with its lower part open is provided with slot  81   d  with downward opening, and with slot  82   d  at the front end of the top wall. And a blocking wall is provided at the front of the slot  82   d.  The resilient clamp stand  83   d  is provided at both sides of the 4th connecting adaptor  80   d,  and resilient boss  84   d  at the top wall. Apart from their own elastic force deriving from materials, the resilient clamp stand  83   d  and resilient boss  84   d  gains additional elastic force in traditional way where only one side of the boss is connected with the main body. Two troughs  85   d  are provided at the top surface of the 4rd connecting adaptor  80   d.    
         [0135]    Based on  FIGS. 31 and 32B , the 4th connecting adaptor is fit into the pivot socket  10 , and positioned by locking the column  12  of the pivot socket  10  into the slot  81   d  of the connecting adaptor, and inserting the trough  85   d  of the connecting adaptor  80   d  into the support wall  14  of the pivot socket  10  when the 4th connecting adaptor is assembled with the pivot socket  10 . 
         [0136]    As shown in  FIG. 31 ,  32 , and  FIGS. 32A and 32B , this invention can be compatible with one existing wiper arm  9 F structure via the said 4th connecting adaptor  80   d.  The said wiper arm  9 E, whose cross section is in U shape with its opening downward, is provided with a bump  92 F at its front end to match up with the slot  82   d  of the 4th connecting adaptor, and clamping surface  93 F at its both side wall to match up with the resilient clamp stand of the 4th connecting adaptor, and clamp hole  94 F, which is provided with barb  941 F to match up with the resilient boss  84   d  of the 4th connecting adaptor, is provided at the top surface of the wiper arm  9 F. When assembled, the wiper arm  9 F is fit into the 4th connecting adaptor  80   d  from the top, enabling the bump  92 F at the front end surface of the wiper arm  9 F to insert into the slot  82   d  of the 4th connecting adaptor and press the back end of the wiper arm  9 F to lock the resilient clamp stand  83   d  into the clamp surface  93 F of the wiper arm  9 F, and the resilient boss  84   d  into the clamp hole  94 F of the wiper arm  9 F at the barb  941 F. In this way, the wiper arm  9 F can be connected with the wiper blade. The said bump  92 F matches up to the 4th connecting adaptor to prevent the wiper arm  9 F from breaking loose upward; front-end surface of the said wiper arm matches up to the blocking wall  86   d  of the 4th connecting adaptor  80   d,  and the resilient boss  83   d  to the clamp surface  93 F, and the resilient boss  84   d  to the barb  941 F to prevent the wiper arm  9 F from breaking loose in forward and backward direction; The said wiper arm is enabled to be positioned in the left or right direction by matching up its U-shape wall with the both sides of the 4th connecting adaptor. 
         [0137]    When the wiper arm  9 F is to be disassembled, the resilient clamp stand  83   d  at both sides of the 4th connecting adaptor is pressed against towards the middle to separate it from the clamp surface  93 F of the wiper arm  9 F. At that moment, the wiper arm  9 F can be turned up to separate the clamp hole  94 F of the wiper arm  9 F from the resilient boss  84   d  of the 4th connecting adaptor, and to pull its bump  92 F out of the slot  82   d.  In this way, the wiper arm  9 F can be separated from the wiper blade. 
         [0138]    The 5th connecting adaptor  80   e  structure of this invention is shown in  FIGS. 33 and 34 . 
         [0139]    The 5th connecting adaptor  80   e,  which is also a hollow body with its lower part open, is provided with a slot  81   e  with downward opening, and with groove  82   e  at the front end of its top wall. The blocking wall  86   e  is formed into the front of the groove  82   e.  The resilient clamp stands  83   e  are also provided at the both sides of the 5th connecting adaptor  80   e.  Additionally, two troughs  85   e  are provided at the top surface of the 5th connecting adaptor  80   e.  Comparing with the above-mentioned 4th connecting adaptor  80   d,  there is no presence of the resilient boss in this preferred embodiment. 
         [0140]    As the said 5th connecting adaptor  80   e  is similar to the 4th connecting adaptor  80   e  in terms of structure, it is assembled with the pivot socket  10  in the same way as that in the above. There is, therefore, no need to go into details. 
         [0141]    As shown in  FIG. 35 , this invention can be compatible with one existing wiper arm  9 G structure via the said 5th connecting adaptor  80   e.  The said wiper arm  9 G, whose front-end cross section is in U shape with its opening downward, is provided with a bump  92 G at its front end surface to match up to the groove  82   e  of the 5th connecting adaptor  80   e,  and with clamp surface  93 G to match up to the resilient clamp stand  83   e  of the 5th connecting adaptor at both side walls. To further their matching well, the matching surface where the said resilient clamp stand  83   e  meets the clamp surface  93 G is a slope. As the said wiper arm  9 G is assembled with the 5th connecting adaptor  80   e  in the way similar to that of assembly of the 5th connecting adaptor  80  with the wiper arm  9 F, there is, therefore, no need to go into details. 
         [0142]    The 6th connecting adaptor  80   f  structure of this invention is shown in  FIG. 36 . 
         [0143]    The said 6th connecting adaptor  80   f,  which is a block body, is provided with a slot  81   f  with downward opening; a groove  82   f  is formed into the back side of the slot  81   f  to access to the latter; and a resilient boss  87   f  is formed into the front of the groove  82   f.  The said 6th connecting adaptor  80   f  is provided with the resilient clamp stand  83   f  at its both sides. Additionally, stepped surfaces are formed into the both side surfaces of the said 6th connecting adaptor, viz, the bigger lower stepped surface  88   f  and smaller upper stepped surface  89   f.  Also, there is a blocking wall  86   f  formed in the front. 
         [0144]    Based on  FIGS. 37 and 38B , the 6th connecting adaptor  80   f  is fit into the inner notch  11  of the pivot socket  10 , and positioned by locking the column  12  of the pivot socket into the slot  81   f  on the adaptor and matching the lower stepped surface of the 6th connecting adaptor with the inner notch  11  of the pivot socket  10 . 
         [0145]    As shown in  FIGS. 37 ,  38 ,  38 A and  38 B, the said the 6th connecting adaptor  80   f  can be compatible with one existing wiper arm  9 H structure. The cross section of the said wiper arm  9 H is in U shape with downward opening, and a bump  92 H is provided at the lower part of both sides of the cross section to match up with the groove  82   f  of the 6th connecting adaptor, and the clamp surface  93 H at the lower part of both side walls to match up with the resilient clamp stand  83   f  of the 6th connecting adaptor. When assembled, the wiper arm  9 H is fit into the 6th connecting adaptor from the top, enabling the bump  92 H of the wiper arm  9 H to insert into the groove  82   f  of the 6th connecting adaptor, and then the back of the wiper arm  9 H is pressed against to lock the resilient clamp stand  83   f  on the 6th connecting adaptor into the clamp surface  93 H of the wiper arm  9 H as well as make the blocking wall  86   f  at the front end of the 6th connecting adaptor lean against the front-end surface of the wiper arm  9 H, which enables the wiper arm  9 H to connect with the wiper blade. However, the said bump  92 H fits into the boss  87   f  of the 6th connecting adaptor  80   f  to prevent the wiper arm  9 H from breaking loose upward; front-end surface of the said wiper arm  9 H matches up to the blocking wall  86   f  of the 6th connecting adaptor  80   f,  and the resilient clamp stand  83   f  to the clamp surface  93 H to prevent the wiper arm  9 F from breaking loose in forward and backward direction; The said wiper arm is enabled to be positioned in the left or right direction by matching up its U-shape wall with the upper stepped surface of both sides of the 6th connecting adaptor  80   f.  When the wiper arm  9 H is to be disassembled, the resilient clamp stand  83   f  at both sides of the 6th connecting adaptor  80   f  is pressed against towards the middle to separate it from the clamp surface  93 H of the wiper arm  9 H. At that moment, the wiper arm  9 H can be pulled out toward the diagonal direction to separate it from the wiper blade.