Stop for a slide fastener, and a method for the manufacture thereof

Abstract

There is provided a stop for a slide fastener. A top plate and a bottom plate are linked with one another at a transversely intermediate position by an integral connecting post. The lower side of the top plate is substantially flat. The bottom plate slopes away from the connecting post to form two leg members provided with a respective end flange pointing towards the top plate, the leg members being adapted to cooperate in use with the top plate to retain fastener tapes therebetween.

Claims

1. A stop for a slide fastener, comprising a top plate and a bottom plate linked with one another at a transversely intermediate position by an integral connecting post, wherein in a condition before the stop is crimped onto the slide fastener, an upper side of the top plate is substantially flat and a lower side of the top plate is flat; and the bottom plate includes a pair of leg members which slope away from the connecting post, wherein the stop is crimped onto fastener tapes of the slide fastener by deforming the pair of leg members of the bottom plate without substantially deforming the top plate, and wherein in a condition after the stop is crimped onto the slide fastener, the pair of leg members are provided with a respective end flange pointing towards the top plate and adapted to cooperate in use with the top plate to retain the fastener tapes therebetween, wherein in the condition after the stop is crimped onto the slide fastener, an upper side of each of the leg members of the bottom plate has a sloping surface extending from the respective flange towards a proximal portion of each of the leg members, and wherein the bottom plate is shaped such that in the condition after the stop is crimped onto the slide fastener an entire lower side of the bottom plate is flat.

2. The stop according to claim 1, wherein in the condition after the stop is crimped onto the slide fastener, the upper side of each of the leg members forms a recess having an essentially trapezoid profile.

3. The stop according to claim 1, wherein in the condition before the stop is crimped onto the slide fastener the upper side of the top plate is stamped or impressed with a logo or a design.

4. The stop according to claim 1, wherein the stop is formed by pressure rolling a wire member.

5. The stop according to claim 1, wherein an uneven member is formed on the lower side of the bottom plate thereof, allowing to distinguish established top and bottom edges of the top plate of the stop.

6. The stop according to claim 5, wherein the uneven member is formed in an edge portion of one end of the stop.

7. The stop according to claim 6, wherein the uneven member is formed centrally in the bottom plate, on the lower side thereof opposed to the connecting post.

8. The stop according to claim 5, wherein the uneven member has a sloping surface inclined with respect to a predetermined direction.

9. A method of detecting whether the stop according to claim 5 is oriented in a predetermined manner, comprising forming the uneven member on a rear side of the stop allowing to establish top and bottom edges of the top plate of the stop, and optically scanning the rear side of the stop to provide signals allowing to determined whether the top and bottom edges are disposed in a predetermined relative position depending on a position of the uneven member.

10. A slide fastener comprising a pair of fastener stringers each comprising the fastener tape provided with a respective row of fastener elements at its edge, a slider for engaging and disengaging the fasteners elements, and the stop according to claim 1, attached to the fastener tapes at one end of the rows of the fastener elements.

11. The slide fastener according to claim 10, wherein the stop has an uneven member formed on a rear side on the stop, allowing to distinguish established top and bottom edges of the top plate of the stop, the uneven member being adjacent the fastener elements.

12. A method for forming a plurality of stops according to claim 1, comprising pressure rolling a wire member into a desired cross-sectional shape, and cutting the wire member to a size of the stops.

13. The stop according to claim 1, wherein the upper side of the top plate has sharp top and bottom edges, and the lower side of the bottom plate has rounded top and bottom edges.

14. The stop according to claim 1, wherein in the condition before the stop is crimped onto the slide fastener, the sloping surface is substantially parallel with respect to the lower side of the top plate.

15. A stop for a slide fastener, comprising a top plate and a bottom plate linked with one another at a transversely intermediate position by an integral connecting post, wherein a condition before the stop is crimped onto the slide fastener, an upper side and a lower side of the top plate are substantially flat; and the bottom plate includes a pair of leg members which slope away from the connecting post, wherein the stop is crimped onto fastener tapes of the slide fastener by deforming the pair of leg members of the bottom plate without substantially deforming the top plate, wherein in a condition after the stop is crimped onto the slide fastener, the pair of leg members are provided with a respective end flange pointing towards the top plate and adapted to cooperate in use with the top plate to retain fastener tapes therebetween, and wherein in the condition before the stop is crimped onto the slide fastener, a proximal portion of each of the leg members of the bottom plate forms a convex protrusion adjacent the connecting post.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further objects, features, aspects and advantages of the present invention will become apparent from the following description, provided purely by way of a non-limiting example, with reference to the accompanying drawings, wherein

(2) FIG. 1 is a partial top-plan view of a slide fastener provided with a stop according to the present invention,

(3) FIG. 2 is a partial perspective view, showing a stop according to the present invention applied to the tapes of a slide fastener;

(4) FIG. 3 is a transverse sectional view of a stop according to the present invention, shown before being crimped onto the tapes of a slide fastener;

(5) FIG. 4 is a transverse sectional view showing the stop of FIG. 3 after being crimped onto the tapes of a slide fastener;

(6) FIG. 5 shows a diagrammatical representation of apparatus for pressure rolling a wire member, for the manufacture of stops according to the present invention;

(7) FIG. 6 is a perspective view illustrating a cutting operation of a pressure-rolled wire member to form a plurality of stops in a method according to the invention;

(8) FIG. 7 is a perspective bottom view of an alternative embodiment of stop according to the present invention;

(9) FIG. 8 is a diagrammatical representation of apparatus for the manufacture of stops according to the embodiment of FIG. 7;

(10) FIG. 9 is a longitudinal sectional view of a stop according to FIG. 7 manufactured with the apparatus of FIG. 8;

(11) FIG. 10 is a diagrammatical representation of apparatus for detecting incorrectly oriented stops of the kind according to FIGS. 7 and 9; and

(12) FIG. 11 is a partial top-plan view of a slide fastener provided with a bottom stop according to FIGS. 7 and 9.

DESCRIPTION OF PREFERRED EMBODIMENTS

(13) The present invention relates to an end stop. Though in the drawings only a bottom stop can be seen, stops according to the invention could be used in a closed slide fastener which has stops at both ends, if desired.

(14) In FIGS. 1 and 2 there is shown a slide fastener 1, of a per se known kind, comprising a pair of fastener stringers, a slider 3, and a bottom end stop 4.

(15) The fastener stringers comprise respective tapes 2 having a plurality of fastener elements or teeth 5 attached on one side edge in the length direction.

(16) The slider 3 allows the fastener elements 5 to pass therethrough, whereby the slider slides on said elements 5 to engage/disengage them.

(17) The bottom end stop 4 is located on the bottom end side of the slide fastener 1 and is attached adjacent to the lowermost fastener elements 5. Said bottom end stop 4 prevents the slider 3 from slipping away downwards from the fastener elements 5.

(18) The fastener elements 5 are constituted of individual elements fixed at predetermined pitches in the length direction of the slide fastener 1. As a preferable example, the fastener elements 5 may be of single unit type, or continuous linear zigzag type, and the material thereof may be metal or resin.

(19) The bottom end stop 4 is made of metal, and is attached by crimping to a core portion 6 formed on one side edge of the fastener tapes 2.

(20) Referring to FIGS. 2 to 4, a stop 4 according to the present invention comprises a top plate 10 and a bottom plate 11, linked with one another at a transversely intermediate position by a connecting post or stem 12.

(21) Preferably, the upper side surface 10a of the top plate 10 is substantially flat.

(22) Conveniently, the upper surface 10a of the stop 4 can be provided with a decoration, such as letters, marks, logos and designs. Such a decoration can be stamped or otherwise impressed onto the stop 4 during the manufacturing process.

(23) Laser engraving can also be used as a technique for providing said decoration on the top plate 10 of the stop 4.

(24) As can be seen in particular in FIGS. 3 and 5, the bottom plate 11 slopes downwards away from the connecting post 12 to form two leg members 11a provided with respective flanges 13 pointing upwards towards the top plate 10.

(25) The leg members 11a are deformable from their edges in the direction of the top plate 10, to crimp the cores 6 of the fastener tapes 2 therebetween as shown in FIGS. 2 and 4.

(26) Prior to the application to the fastener tapes the bottom plate 11 of the stop 4 is shaped such that after being deformed or “closed”, i.e. in the condition of use, the lower side surface 11b thereof is also substantially flat as shown in FIGS. 2 and 4.

(27) The stop 4 can be attached to the fastener tapes 2 without deforming the top plate 10 thereof which possibly bears a decoration, and by applying pressure solely to the shaped leg members 11a.

(28) Thanks to the fact that in the condition of use both the upper surface 10a and the lower surface 11b of the stop 4 are substantially flat, the stop 4 as a whole is pleasantly perceived as relatively smoother than the stops according to the prior art. Such a smooth feel is particularly of interest in connection with the lower side surface 11b of the bottom plate 11, which in use in a garment or the like will be on the inside thereof.

(29) As anticipated above, the lower surface of the top plate 10 is essentially flat, said lower surface having no flanges protruding towards the bottom plate 11. This feature requires less material and makes the manufacture of the stop more straightforward.

(30) Since the top plate 10 is not bent during the attaching process of the stop, the decoration possibly provided on the upper surface thereof is protected and consistent.

(31) Referring once again to FIGS. 3 and 4, the proximal portion of each leg member 11a forms a convex protrusion 11c adjacent the connecting post 12. Said protrusion 11c is formed on the upper side of each leg member 11a, at the place where the leg member starts to sprout from the connecting post 12.

(32) As can be seen in particular in FIG. 4, when the stop 4 is attached to the cores 6 of the tapes 2, said cores 6 are moved downwards, somewhat out of the plane of the fastener.

(33) Since the cores 6 of the tapes 2 are substantially circular in shape, in the absence of the protrusions 11c gaps could be formed between the connecting post 12 and said cores 6. The protrusions 11c substantially “fill” such possible gaps, holding the cores 6 in position better, and supporting the rest of the leg members 11a when attempts are made to pull the tapes 2 out of the stop 4.

(34) As already mentioned above, on the extremity of the leg members 11a there is provided a respective flange 13 which points upwards towards the upper plate 10, to hold the corresponding core 6 and tape 2 in place. The top of each flange 13 joins with the relevant protrusion 11c through two adjacent, essentially flat surfaces 11d and 11e.

(35) Surface 11e is the lowest or bottom surface, substantially parallel with the lower surface 11b of the relevant leg member 11a.

(36) In the deformed condition of use of the stop 4 shown in FIG. 4, the surface 11d stretches from the flange 13 in a flat sloping surface which joins with surface 11e in a continuous manner, the latter being essentially parallel with the top plate 10 and the bottom plate 11 of the stop 4.

(37) The protrusion 11c is at the intersection of the base of the connecting post 12 and surface 11e.

(38) As a whole, the surface of the protrusion 11c and the essentially flat surfaces 11d and 11e define a sort of groove having a substantially trapezoid transverse profile. This trapezium-like profile encircles the deformed core 6 of the corresponding tape 2, cooperating to ensure that no free gaps are left around it, reducing movement and ensuring a stronger grip.

(39) A distinguishing feature of the stop according to the present invention is that its transverse profile allows the manufacture thereof by properly shaping, in a pressure rolling process, a blank wire. This technique allows easier control of the quality of the metal, avoiding any local weaknesses in the product which, with conventional techniques like die casting, may be occasioned by cracking due to the need to heat and cool the metal.

(40) With reference to FIG. 5, by means of per se known pressure rolling apparatus a blank metal wire can be continuously shaped so as to assume a final cross-sectional profile corresponding to that of a stop according to the present invention prior to its crimping onto the fastener tapes.

(41) Such a plastic deformation can be carried out using properly shaped rollers, such as the upper and lower rollers 100, 101 and the side rollers 102, partially and diagrammatically shown in FIG. 5.

(42) The result of such a pressure rolling process is a continuous bar 200 (FIG. 6) having the transverse cross section of the desired stop prior to application to the fastener tapes.

(43) Such a rolled wire member or bar 200 can thereafter be cut to the size of the stops, so as to obtain therefrom a plurality of stops 4.

(44) With a view to facilitating and improving the pressure rolling process, care is taken that there are only smooth surfaces in the stop 4, ensuring that the rolled wire member comes freely out of the pressure roller assembly. With reference to FIG. 5, it can be appreciated that the upper and lower surfaces of the top plate 10 are substantially flat, with no flanges or other protrusions. Furthermore, the sloping surface is essentially parallel or at a small angle with respect to the plane of the lower surface of the top plate 10.

(45) If the stops 4 obtained by the above-described method are to be provided with a decoration on the top plate 10 thereof, such a decoration can be engraved or otherwise provided on the top surface of the bar 200, before cutting it into a plurality of individual stops.

(46) As an alternative, the individual stops 4 could be provided with the respective decoration after being cut from the bar 200.

(47) Another embodiment of a bottom stop according to the present invention will be now described with reference to FIGS. 7 and 11.

(48) In FIGS. 7 and 11 parts which have already been described in connection with FIGS. 1-6 have been attributed again the same reference numerals previously utilized.

(49) The bottom stop 4 shown in particular in FIG. 7 represents a further improvement allowing the automatical detection of an established “top” and “bottom” for the stop.

(50) When a stop 4 is (or is to be) provided with a logo and/or design on its top surface or front face 10a, if the logo and/or design is symmetrical about the horizontal axis, distinguishing the top and bottom edges of the front face of the stop may be not particularly important.

(51) However, when this is not the case, it becomes necessary to establish the direction in which the stop 4 should face before it is attached to the fastener tapes.

(52) The embodiment which will be now described with reference to FIG. 7-11 aims to solving that problem.

(53) The bottom stop 4 shown in FIG. 7 is provided in a rear side portion thereof with a formation 20, shaped and positioned such as to allow the differentiation of the top edge 10t of the front face 10a of the top plate 10 from the bottom edge 10b of the same.

(54) With reference for instance to FIG. 11, by the top edge 10t of the front face 10a it is meant herein the edge of said face 10a which is adjacent the fastener elements or teeth 5, and by the bottom edge 10b is meant the edge of said surface 10a facing the opposite direction.

(55) As shown in FIG. 7, the formation 20 is in general an uneven member or surface portion, and a recess in particular.

(56) In alternative embodiments said uneven member 20 may be a protrusion.

(57) The uneven member 20 can be conveniently provided in an edge portion of the stop, in particular centrally in an edge portion 11t of the lower plate 11, as shown in FIG. 7, on the side thereof opposed to the connecting post 12.

(58) In the embodiment shown in the drawings the recessed uneven member 20 is essentially channel-shaped, and includes a sloping surface portion 20a extending between two more or less parallel side surfaces 20b.

(59) In the embodiment shown in the drawings the sloping surface 20a is inclined with respect to a direction orthogonal to the front face or upper side surface 10a of the stop 4.

(60) Preferably, the uneven member 20 is provided in the end of the stop 4 which, when the latter has been affixed to the fastener tapes 2, is the top end of the stop, adjacent the elements or teeth 5, as shown in FIG. 11. This solution is beneficial because the top end portion of the stop 4 is generally harder to see and it reduces the possibility that the edges or points of the uneven member 20 may scrape that with which it may come into contact.

(61) FIG. 8 shows an exemplary apparatus for the manufacture of stops according to FIG. 7, comprising a first press member 300 provided with a shaping surface 300a adapted to create a logo and/or a design 40 engraved into the front face 10a of the top plate of each stop 4 as shown in FIG. 9.

(62) The apparatus of FIG. 8 comprises further an upper stamping cutting press member 301 and a cooperating lower cutting press member or die 302 provided with a hole 302a having a length L equal to the desired longitudinal (top to bottom) size of the stops 4.

(63) The die 302 has an upper surface 302b which is generally flat, but for a protrusion 302c which has a shape essentially complementary to that of the uneven member 20 to be provided in the stops 4.

(64) The protrusion 302c is immediately adjacent the hole 302a of the die 302, whereby said hole has a first sharp cutting edge 302d and a second sharp cutting edge 302e at slightly different heights or levels. Said cutting edges are longitudinally separated by the distance L.

(65) The upper press member 301 has a generally flat lower surface 301a, with longitudinally opposed stamping/cutting edges 301d and 301e, longitudinally separated essentially by the distance L.

(66) The apparatus of FIG. 8 operates essentially in accordance with the method already disclosed with reference to FIG. 6: a wire member 200 is sequentially stamped/cut to the side of the stops, so as to obtain therefrom a plurality of stops 4.

(67) In particular, for cutting a stop 4 the wire member 200 is disposed relative to the stamping/cutting press member 301 and the cooperating die 302 in a position like that shows in FIG. 8, such that its leading end 200a extends above the upper surface 302b of said die, beyond the cutting edge 302d thereof by a small amount indicated ε in FIG. 8.

(68) The press member 301 is then moved toward the die 302, and a stop 4 is stamped or cut away from the wire 200. In this process, a thin waste “slice” is cut away from the leading portion of the wire 200, and an uneven member 20 is created in the “new” leading portion of said wire 200 which will be subsequently stamped or cut to form the next stop 4.

(69) Thus, at each stamping/cutting step a new stop 4 is formed, wherein the respective uneven member 20 had been provided in the immediately preceding stamping/cutting step.

(70) Before each stamping/cutting operation, the leading end of the wire 200 is disposed, relative to the press member 301 and the die 302, in the same position described above, i.e. longitudinally beyond the cutting edge 302d of the hole 302 by an amount c.

(71) Thus at each stamping/cutting step a thin waste “slice” of excess material is cut away from the leading end of the wire 200.

(72) Such a cutting process guarantees that the thus obtained stops 4 are provided with sharp upper top and bottom edges 10t, 10b (FIG. 9).

(73) The above-described process is moreover such that the top edge portion 11t and the lower bottom edge portion of the thus obtained stops 4 are instead rounded.

(74) However, by reversing the position of the wire 200 between the press member 301 and the die 302, a rounded cut would be obtained at the top and bottom edges 10t, 10b of the front face 10a of the stops, and sharp cuts would be obtained at the top edge portion 11t and the lower bottom edge portion.

(75) With the above stamping/cutting process, the provision of the logo and/or design 40 on the front face of the stops 4 can be carried out before or after the stops 4 have been severed out from the wire member 200. The press member 301 might also be provided with a shaping surface adapted to engrave the logo and/or design 40 into each stop 4 while this is being stamped/cut away from the wire member 200.

(76) Finally, FIG. 10 shows a simple diagram of a process for identifying whether each bottom stop 4 in a row is oriented in the correct position or not, before the attachment thereof to the stringers of a fastener.

(77) In FIG. 10 a row of stops 4 are imagined to flow from the right to the left from a feeder (not shown, but known per se) to a mechanism for attaching them to corresponding slide fasteners. A sensor 400 of a known type, such as a CCD camera, is used to scan the row of flowing stops 4, to determine whether they are oriented correctly or not. In FIG. 10 the rightmost bottom stop 4 is oriented wrongly, and this may be detected from the signals provided by the sensor 400. To that end, the sensor 400 can be a relatively cheap light sensor: a light beam impinging on the sloping surface 20a of the uneven member 20 of a wrongly oriented stop 4 will not reflect back into a collection/sensing point on the sensor because of the deflection of the light beam by the slope.

(78) Naturally, the principle of the invention remaining the same, various details may be varied with the respect to what has been described above and illustrated in the drawings, without departing thereby from the scope of the invention as defined in the annexed claims.

(79) Thus, for instance, an additional and different material can be attached to the upper side of the top plate 10.

(80) Different designs can be created by plating effects on the metal, either by addition or removal of a coating or a colouring.

(81) The upper surface 10a of the top plate 10 does not have to be entirely flat.

(82) As to the metal used for the manufacture of the stop, aluminum and aluminum alloys, copper and copper alloys, zinc and zinc alloys can be advantageously taken into consideration. Aluminum (or alloys thereof) and copper (or alloys thereof) are most convenient for use in the claimed method.

(83) The shape of the stop below the design-carrying upper surface can be a profile.

(84) A better quality of a logo or design stamped onto the stop can be achieved when the logo or design is impressed prior to cutting the rolled blank wire member in the claimed method, as the “plastic flow” of the metal will prevent any unwanted deformation of the leg members of the stop.