A slider pull tab

Abstract: A slider pull tab (18) for slide fasteners has a connecting means (20) formed of a rigid material for connecting a pull tab body (19, 19') of an elastic, flexible material to a slider (10). The connecting means (20) has a chamber (21) and a window (21g) communicating therewith for fitting engagement with an anchoring member (23). A mold material (M) is injection-molded to form the pull tab (19, 19') simultaneously with the formation of an integral joint in the chamber (21) in which the mold material (M) is anchored in place by the anchoring member (23) relative to the connecting means (20).

Description: This invention relates to sliders for slide fasteners, more particularly to a slider pull tab made of an elastic, flexible material such as synthetic rubber, synthetic leather or other elastic synthetic resinous materials, and to a method for making such a pull tab. There are known a variety of slide fastener sliders having different forms and designs of pull tab which are tailored to meet with the particular specifications set up by the garment manufactures who produce all sorts of garment articles ranging from clothing, sports wear, sports equipment to bags, etc. There are known a variety of pull tabs connected to slide fastener sliders for moving the latter reciprocally along a pair of fastener stringers. For ease of manipulation, aesthetic preference and other advantages over conventional metal counterparts, there is a growing demand for slider pull tabs made of a soft rubber, resin or other such flexible material that can render the pull tab flexible or pliable. Different means have been proposed to provide satisfactory connection between the body of the pull tab and the body of the slider. Japanese Laid-Open Utility Model Publication No. 62-102407 proposes the use of a connector pivotally linked at one end to a trunnion on a slider body, in which case the other end of the connector is embedded in a web of elastic, flexible rubber or resin forming a pull tab. Since the connector is joined to a limited area of the elastic web material of the pull tab, its strength of pull relative to the slider is rather weak, leading to damage or separation from the slider over prolonged periods of time in use. Another proposal is made in Japanese Laid-Open Patent Publication No. 2-45006 in which two metallic connectors are used to connect a pull tab body to a slider, the pull tab body being cast-molded together with one of the two connectors having a reinforcing strip. This prior device is complicated in construction and hence difficult to manufacture, added by the presence of such a reinforcing strip which would make the pull tab as a whole less flexible. EP-A-0 369 258 discloses a slider pull tab for a slide fastener comprising a connector means including a first and a second connector made from a rigid material and a grip part formed by injection molding of an elastic, soft resin. The connector means has openings which are filled by the material of the grip part. Since the connector has two connector means the construction is complicated and also difficult to manufacture. With the foregoing drawbacks of the prior art in view, the present invention seeks to provide a slider pull tab for a slide fastener which has a highly mechanically strong joint relative to the slider and yet retains sufficient flexibility to facilitate manipulation of the slider. As claimed a slider pull tab for a slide fastener comprises a pull tab body having a web portion formed by molding an elastic, flexible material; a connecting means made from a rigid material and having a chamber wherein molding material is received forming an integral joint with one end of the pull tab body. According to the invention the connecting means has a window communicating with the chamber and an anchoring member extends through the window into the chamber. The anchoring member is provided with a retainer means for anchoring the web portion of the pull tab body. The invention also relates to a method of making a slider pull tab, as disclosed in claim 7. The above and other features and advantages of the invention will appear more apparent from the following detailed description taken in connection with the accompanying drawings. Like reference numerals refer to like or corresponding parts throughout the several views. Figure 1 is perspective view of a slider having a pull tab embodying the invention; Figure 2 is a longitudinal cross-sectioned plan view of the slider pull tab shown in Figure1; Figure 3 is a longitudinal cross-sectional slide view of the same; Figure 4 is an exploded perspective view of a connecting means for connecting the pull tab body to the slider; Figure 5 is an exploded perspective view of a modified form of connecting means; Figure 6 is a perspective view of a modified component part of the connecting means; Figure 7 is a plan view of a modified form of slider pull tab according to the invention; Figure 8 is a schematic longitudinal cross-sectional view of a moulding device utilized to form the pull tab of Figure 3 and shown separated prior to charging of a molding material; and Figure 9 is a view similar to Figure 8 but showing the mold closed for charging a molding material. Referring now to the drawings and Figure 1 in particular, there is shown a slider 10 connected to a pull tab 18 embodying the invention which is used to open and close a slide fastener. The slider 10 comprises a slider body 11 formed by an upper flange 12 and a lower flange 13 defining therebetween a guide channel 14 for the passage of a slide fastener not shown and connected together at one of its ends by a neck 15 (commonly known as a diamond), and an arch-shaped trunnion 16 having an aperture 17 for pivotally receiving the pull tab 18. The pull tab 18 comprises a pull tab body 19 formed from an elastic, flexible material such as soft synthetic rubber, resin or other moldable materials and having a web portion 19a and a loop portion 19b. The pull tab 18 includes a connecting means or clamper 20 made of a metal or other rigid materials and connected at one of its ends with the web portion 19a and at the opposite end with the slider 10. As better shown in Figure 4, the clamper 20 has a rectangular box 21 formed by an upper wall 21a, a lower wall 21b, a pair of side walls 21c, 21c and a front end wall 21d jointly defining therebetween a rectangular chamber 21e for receiving through an inlet 21f a molding material for purposes hereinafter to be described. Extending from the front end wall 21d is an annular hook 22 for pivotal engagement with the trunnion 16 as shown in Figure 1. Formed centrally in the upper wall 21a of the clamper 20 is a rectangular window 21g communicating with the chamber 21e for receptive engagement with an anchoring member 23 and having a flared marginal edge 21g'. The anchoring member 23 has an upper rectangular plate 23a and a lower rectangular plate 23b joined together in spaced relation by a retaining post 23c to provide on opposite sides thereof a pair of bays 23d, 23d to be filled with a molding material in a manner hereinafter to be described. The upper plate 23a has tapered peripheral edges 23a' dimensioned to snugly fit complementarily with the flared marginal edge 21g' of the window 21g so as to make the upper surface of the upper plate 23a lie substantially flat and flush with the upper surface of the upper wall 21a of the clamper 20, as shown in Figure 3. Turning to Figures 8 and 9, there is schematically shown an injection-molding device 100 which comprises a pair of vertically opposed mold halves 101 and 102 each having first indentical cavity halves 103, 103 for forming the pull tab body 19 and second cavity halves 104, 105 configured to respectively receive the upper and lower half portions of the clamper 20. Assembled with the anchoring member 23, the clamper 20 is placed in the second lower cavity 105 as shown in Figure 8, followed by closure of the upper and lower molds 101 and 102 as shown in Figure 9 whereupon a molding material M is fed through a runner 106 and a gate 107 into the first cavity 103 and progressively further into the second cavity 104, 105 until the material M completely fills up the chamber 21e of the clamper 20 including the bays 23d, 23d. As the molding operation is complete under conditions well known in the art, the molds 101, 102 are opened to produce an integral pull tab structure having a substantial mass of molding material M filled and cured in a relatively large space or chamber 21e of the clamper 20 to form a firm, strong joint between the pull tab body 19 and the clamper 20. Figure 5 illustrates a modified form of clamper 20' which differs from the clamper 20 already described in that the window 21g is formed in one of the side walls 21c, 21c and further in that an anchoring member 23' is provided with fins 23e projecting laterally on opposite sides of the post 23c between the upper plate 23a and the lower plate 23b. Figure 6 shows a modified form of anchoring member 23'' which comprises a rectangular upper plate 23a similar to that shown in Figure 4 and an "I" beam retainer 23c' extending downwardly therefrom. There may be other modifications of the clamper 20 conceivable within the context of the appended claims. Figure 7 shows a modified form of pull tab body 19' which differs from the counterpart 19 only in that it is made up solely from the web portion 19a devoid of the loop portion 19b. 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 specifically described.

Claims: A slider pull tab (18) for a slide fastener which comprises a pull tab body (19, 19') having a web portion (19a) formed by molding an elastic, flexible material; a connecting means (20, 20') made from a rigid material and having a chamber (21e) wherein molding material (M) is received forming an integral joint with one end of the pull tab body (19, 19'), characterized in that the connecting means (20, 20') has a window (21g) communicating with the chamber (21e) and an anchoring member (23, 23', 23'') extends through the window (21g) into the chamber (21e) and the anchoring member (23, 23', 23'') is provided with a retainer means (23c, 23e, 23c') for anchoring the web portion of the pull tab body (19, 19'). A slider pull tab (18) for a slide fastener according to claim 1 characterized in that said window (21g) has a flared marginal edge (21g') and said anchoring member (23) has a tapered peripheral edge (23a') dimensioned to fit complementarily with said flared edge (21g'). A slider pull tab (18) for a slide fastener according to claim 1 characterized in that said pull tab body (19, 19') is formed by injection-molding. A slide pull tab (18) for a slide fastener according to claim 1 characterized in that said window (21g) is formed in the upper portion of said connecting means (20). A slide pull tab (18) for a slide fastener according to claim 1 characterized in that said window (21g) is formed in either side of said connecting means (20). A slide pull tab (18) for a slide fastener according to claim 1 characterized in that said pull tab body (19) has a loop portion (19b). A method of making a slider pull tab (18) which comprises mounting a connecting means (20, 20') made from rigid material in a cavity (105) of a lower mold (102), said connecting means (20, 20') having a chamber (21e) for receiving a molding material (M) and a window (21g) communicating with said chamber (21e), inserting an anchoring member (23, 23', 23'') through said window (21g) into said connecting means (20,20'), closing an upper mold (101) over said lower mold (102) and injecting the molding material (M) thereby forming a pull tab body (19, 19') integrally with said connecting means (20, 20').

Inventors: EBATA HIROKAZU, EBATA, HIROKAZU
Applicants: YKK CORP, YKK CORPORATION
Application year: 1993
Main classification: A44B19
IPC codes: A44B19, B29C45