Abstract:
A buckle comprising a male member and a female member releasably engageable therewith, the female member including a pair of resilient arms serving as a release lever and a pair of inwardly directed flanges. The resilient arms each have a stop finger normally spaced apart from but abuttingly engageable with the flange when lateral pull is exerted upon the release lever.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a buckle for releasably connecting loose ends of a belt, strap and other elongate fastening devices applied to trousers, skirts, bags and like garment articles. 
     2. Prior Art 
     There have been proposed numerous buckles of the character mentioned. Some were easy to use but structurally vulnerable. Design considerations have therefore been directed toward strengthening the buckle body, particularly a release lever portion thereof, which is susceptible to damage by the influence of external stresses. 
     Japanese Utility Model Laid-Open Publication No. 59-31908 discloses a buckle (FIG. 5) comprising a male member 100 and a female member 101 releasably engageable therewith in a manner well known in the art, the female member 101 having a pair of release levers 102 to be manipulated to resiliently couple and uncouple the male and female members 100 and 101, each of which release lever has a prong 103 projecting longitudinally of the buckle body, and the female member 101 further having on opposite sides thereof a pair of shielding lugs 104 projecting longitudinally toward the release levers 102 and abuttingly engageable with the prongs 103 to restrict excessive outward displacement of the release levers 102 when lateral stresses are applied. This prior art device advantageously protects the release lever 102 against possible damage resulting from lateral stresses tending to pull the levers 102 laterally outwardly. However, since the release levers 102 are exposed outwardly beyond the female member 101, they are vulnerable against external forces exerted in a direction substantially perpendicular to the general plane of the buckle, or from either surface of the buckle. 
     Another prior buckle device (FIGS. 6 and 7) is disclosed in Japanese Utility Model Laid-Open Publication No. 61-202212 in which a female member 200 has embraced therein a substantial portion of each of a pair of release levers 201, each of which has a downwardly projecting lug 202 lockable in a slot 203 formed in the bottom wall of the female member 200 This arrangement appears to overcome the problem of the release lever associated with external stresses applied in a direction both perpendicular to and parallel with the general plane of the buckle. However, the lugs 202 would be susceptible to deformation in contact with the peripheral walls of the slots 203 or liable to spin out of the slot 203 when the buckle was subjected to increased stresses, eventually leading to failure or damage of the release levers 201. This would be more likely with relatively thin, small-sized buckles. 
     SUMMARY OF THE INVENTION 
     With foregoing drawbacks of the prior art in view, the present invention seeks to provide an improved buckle which incorporates such structural features which will effectively hold its release levers harmless against external forces exerted in a direction both perpendicular to and parallel with the general place of the buckle. 
     This and other objects and features of the invention will become apparent from reading the following detailed description with reference to the accompanying drawings which illustrate by way of example a preferred embodiment. 
     According to the invention, there is provided a buckle comprising a male member having a pair of resilient legs and a female member having a pair of sub-chambers for receiving the respective resilient legs, the female member including a casing formed by an upper plate and a lower plate disposed in spaced parallel relationship and defining therebetween the sub-chambers, the upper and lower plates respectively having inwardly directed flanges, and a pair of resilient arms respectively having inwardly directed neck portions movable between the flanges, and a stop finger normally spaced apart from but engageable with one of the flanges when lateral stresses are exerted upon the resilient arms. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a plan, partly sectional, view of a female or socket member constituting one part of a buckle provided in accordance with the invention; 
     FIG. 2 is a side elevational view of the female member shown in FIG. 1; 
     FIG. 3 is a transverse cross-sectional view taken on the line III--III of FIG. 1; 
     FIG. 4 is a longitudinal cross-sectional view of the female member of FIG. 1 shown coupled with a male or plug member constituting another part of the buckle; 
     FIG. 5 is a plan view of one prior art buckle; 
     FIG. 6 is a plan view of another prior art; and 
     FIG. 7 is a transverse cross-sectional view taken on the line VII--VII of FIG. 6. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings and FIG. 1 in particular, there is shown a female or socket member 11 constituting one part of a buckle 10 embodying the invention which is molded into a polygonal structure from a suitable synthetic resin such as polyacetal, nylon and polypropylene. The female member 10 comprises a body 11&#39; including a casing 12 generally rectangular in shape which is formed by a pair of upper plate and lower plates 13, 14 disposed in spaced parallel relationship and defining therebetween a chamber 15 for receiving a male or plug member 16 (FIG. 4). The upper and lower plates 13, 14 are centrally joined together by a vertical partition wall 17 which divides the chamber 15 into two identical sub-chambers 15a and 15b. The casing 12 has an opening 18 in opposite sides thereof disposed remote from the partition wall 17 in communication with each of the subchambers 15a, 15b and defined by inwardly directed upper and lower flanges 19, 20 which extend from the upper and lower plates 13, 14, respectively and which have respective end surfaces 19a, 20a in confronting relation to each other. 
     A pair of resilient arms 21, 22 extend integrally from opposite sides of the body 11&#39; of the female member 11 and are elastically deformable to serve as a release lever to releasably hold the male member 16 in place within the chamber 15 in a manner hereinafter to be described. The resilient arms 21 and 22 each have an outwardly bulged portion 21a, (22a) to be gripped by hand in manipulating the release lever and an inwardly directed neck portion 21b, (22b) having adjacent to a distal free end 23 a pair of upper and lower stop fingers 24 and 25 respectively projecting upwardly and downwardly within the chamber 15 beyond the respective end surfaces 19a, 20a of the flanges 19, 20 as better shown in FIG. 3. The neck portion 21b, (22b) is reduced in thickness to be able to move through the opening 18 between the upper and lower flanges 19, 20 and merge at the opposite end (remote from the distal end 23) with upper and lower shoulder portions 26, 27 which normally (when the buckle is not in use) define, with an outer lateral side wall 19b, (20b) of the flange 19, (20), a gap g of a predetermined width governing the inward flexing movement of the release lever (resilient arms 21, 22). In such normal position of the resilient arms 21, 22, the stop fingers 24, 25 are held apart from respective inner side wall 19c, 20c of the flanges 19, 20. However, when lateral stresses are applied to pull the resilient arms 21, 22 (release lever) laterally outwardly, the stop fingers 24, 25 come into abutting engagement with the respective inner side walls 19c, 20c of the flanges 19, 20 to absorb thereat the lateral stresses so as to prevent detachment of the resilient arms 21, 22 from the body 11&#39;. 
     An aperture 28 is formed in the lower plate 14 of the casing 12 for receiving therein the lower stop finger 25 when the resilient arms 21, 22 are held in the normal position, for which purpose the lower stop finger 25 may conveniently be slightly longer than the upper stop finger 24. 
     Designated at 29 and 30 are a pair of guide rails spaced apart from each other across the partition wall 17 and respectively defining with the partition wall 17 the sub-chambers 15a and 15b for the passage and reception therethrough of a pair of resilient legs 31 and 32 of the male member 16 constituting another part of the buckle 10. The male member 16 is conventional with apertures 33 for the insertion of a loose end of a belt or the like. 
     When coupling the male member 16 with the female member 11, this is done by inserting the legs 31, 32 through the sub-chambers 15a, 15b respectively until the legs 31, 32 are brought into hooked engagement with the respective guide rails 29, 30 in a well known manner as shown in FIG. 4. When separating the male member 16 from the female member 11, this is done by depressing the resilient arms 21, 22 at the bulged portions 21a, 22a inwardly toward each other so as to release the legs 31, 32 by elastic deformation from the guide rails 29, 30 also in a well known manner. 
     Obviously, various modifications and variations of the present invention are possible in the light of the above teaching. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.