Patent Publication Number: US-6704977-B1

Title: Strap buckle

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a buckle for joining straps and, more particularly, to such a buckle that can smoothly and stably be set into the locking position and, does not hook clothes or any other external bodies accidentally. 
     2. Description of the Related Art 
     A variety of buckles are known for use to fasten two straps together. FIGS. 7 and 8 show a buckle for this purpose according to the prior art. According to this design, the buckle B is comprised of a male buckle member B 1  and a female buckle member B 2 . The female buckle member B 2  has a front receiving open side B 21 , two retaining side holes B 22 , and a longitudinal guide track B 211  inside the front receiving open side B 21 . The male buckle member B 1  has a forwardly extended middle guide rod B 12 , two springy arms B 11  bilaterally arranged in parallel at two sides of the middle guide rod B 12 , two retaining blocks B 13  respectively formed integral with the remote end of each of the springy arms B 11 , and two stop edges B 14  respectively formed in between the springy arms B 11  and the retaining blocks B 13  at an outer side. When fastening the buckle B, insert the middle guide rod B 12  of the male buckle member B 1  into the longitudinal guide track B 211  of the female buckle member B 2  to force the retaining blocks B 13  and the springy arms B 11  into the front receiving open side B 21  of the female buckle member B 2 . When set into position, the retaining blocks B 13  are respectively bilaterally forced outwards by the springy power of the springy arms B 11  into the retaining side holes B 22 , keeping the stop edges B 14  of the male buckle member B 1  respectively stopped at the respective front side edges B 221  of the retaining side holes B 22 , and therefore the male buckle member B 1  is prohibited from backward movement relative to the female buckle member B 2 . This design of buckle is still not satisfactory in function for the drawbacks below: 
     1. This design of buckle is not suitable for use in a small article (shoe, wrist watch, body belt, etc.). Because the user must squeeze the retaining blocks B 13  inwards with the fingers to disengage the stop edges B 14  from the front side edges B 221  of the retaining side holes B 22  when unfastening the buckle B, the buckle members B 1  and B 2  must have certain dimensions convenient for operation with the fingers. 
     2. Because the middle guide rod B 12  protrudes from the front side of the male buckle member B 1  at a distance, it may hook or damage the clothes or other external bodies accidentally. 
     3. Because the male buckle member B 1  and the female buckle member B 2  must match each other precisely, the precision requirement is critical, resulting in high manufacturing cost. 
     4. When fastening the buckle B, the middle guide rod B 12  of the male buckle member B 1  must be carefully aimed at the longitudinal guide track B 211  of the female buckle member B 2  before inserting the male buckle member B 1  into the female buckle member B 2 . The user may set the male buckle member B 1  into the female buckle member B 2  in position after several attempts. 
     Therefore, it is desirable to provide a buckle for joining two straps that eliminates the aforesaid drawbacks. 
     SUMMARY OF THE INVENTION 
     The present invention has been accomplished under the circumstances in view. It is therefore the main object of the present invention to provide a buckle, which is easy to operate. It is another object of the present invention to provide a buckle, which does not hook the clothes or external bodies when unlocked. It is still another object of the present invention to provide a buckle, which can be closely attached to the surface of the article in which it is installed when locked. According to one aspect of the present invention, the male buckle member has a hook block at the front bottom side, and the female buckle member has an opening adapted to receive the hook block of the male buckle member and a springy support suspending in the opening and adapted to push the hook block forwards into engagement with a part of the female buckle member when the user released the female buckle member from the hand after the hook block had been inserted into the opening by force to push the springy support backwards. According to another aspect of the present invention, the female buckle member has a retaining groove provided in a front side within the opening, and the hook block of the male buckle member has a backwardly extended hooked portion adapted to engage the retaining groove of the female buckle member to positively secure the male buckle member to the female buckle member. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an elevational assembly view of a buckle according to the present invention. 
     FIG. 2 is a perspective exploded view of the buckle according to the present invention. 
     FIG. 3 is a schematic side view in section of the present invention before the connection of the male buckle member to the female buckle member. 
     FIG. 4 is similar to FIG. 3 but showing the male buckle member attached to the female buckle member but not set into position. 
     FIG. 5 is similar to FIG. 4 but showing the hook block of the male buckle member set into the opening of the female buckle member. 
     FIG. 6 is similar to FIG. 5 but showing the hooked portion of the hook block of the male buckle member hooked in the retaining groove inside the opening of the female buckle member. 
     FIG. 7 is an exploded view of a buckle according to the prior art. 
     FIG. 8 is a top view in section of the prior art buckle, showing the male buckle member set into the female buckle member. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIGS.  1 ˜ 3 , a buckle for joining two straps (or the ends of a strap) in accordance with the present invention is shown comprised of a male buckle member  1  and a female buckle member  2 . 
     The male buckle member  1  comprises a mounting base  11 , a flat front coupling portion  12  forwardly extended from the mounting base  11  in flush with the top surface of the mounting base  11 , an insertion hole  111  cut through the mounting base  11 , and a hook block  121  downwardly extended from the front sidewall of the front coupling portion  12 . The hook block  121  has a backwardly protruded bottom hooked portion  1211 . 
     The female buckle member  2  comprises a mounting base  21 , a flat front coupling portion  22  forwardly extended from the mounting base  21  in flush with the bottom surface of the mounting base  21 , an insertion hole  211  cut through the mounting base  21 , an opening  221  cut through the flat front coupling portion  22  and a part of the mounting base  21 , a retaining groove  2211  formed in a front side inside the opening  221  remote from the mounting base  21 , and a springy support  222  formed integral with the mounting base  21  and suspending in the opening  221  opposite to the retaining groove  2211 . The springy support  222  comprises a springy arm  2221  downwardly extended from the top of the mounting base  21  and suspended in the opening  221 , and a cylindrical stop block  2222  transversely located on the free end of the springy arm  2221 . After strap members  3  have been respectively fastened to the insertion holes  111  and  211  of the buckle members  1  and  2 , the buckle members  1  and  2  can be fastened together to join the strap members  3 . 
     The buckle fastening procedure is outlined hereinafter with reference to FIGS.  3 ˜ 6 , the male buckle member  1  is held with one hand, keeping the flat front coupling portion  12  of the male buckle member  1  spaced above the flat front coupling portion  22  of the female buckle member  2  and the hooked block  121  aimed at the opening  221  (see FIG.  3 ), and then lower the male buckle  1  to force the hook block  121  against the cylindrical stop block  2222  (see FIG. 4) and to push the springy arm  2221  backwards for enabling the hook block  121  to be set into the opening  221  (see FIG.  5 ), and then release the hand from the female buckle member  1  for enabling the hook block  121  to be pushed backwards by the spring power of the spring arm  2221  to force the hooked portion  1211  into engagement with the retaining groove  2211  (see FIG.  6 ). When fastened up, a gap A is left between the front sidewall of the flat front coupling portion  12  of the male buckle member  1  and the mounting base  21  of the female buckle member  2  for enabling the user to push the male buckle member  1  forwards against the cylindrical stop block  2222  of the springy arm  2221  to disengage the hooked portion  1211  from the retaining groove  2211 , and to further disconnect the male buckle member  1  from the female buckle member. 
     A prototype of buckle has been constructed with the features of the annexed drawings of FIGS.  1 ˜ 6 . The buckle functions smoothly to provide all of the features discussed earlier. 
     Although a particular embodiment of the invention has been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.