US2972793A - Slider for slide fasteners - Google Patents

Description

. 1961' J. E. BURBANK 2,972,793

SLIDER FOR SLIDE FASTENERS Filed June 19, 1956 2 Sheets- -Sheet 2 FIGS. 4 g

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. a if I l INVENTOR JOHN E. BURBANK BY Mb- SMbA-qL -J-v-m-e u)- Cw H ISATTORNEYS filament.

SLIDER non suns FASTENERS John E. Burbank, Stamford, Conn., assignor, by mesne assignments, to Cue Fasteners, Inc., a corporation of New York Filed June 19, 1956, Ser. No. 592,286

4 Claims. (Cl. 24 -205.14)

This invention relates to improvements in slide fasteners and particularly to improved lock-type sliders for slide fasteners of the type having interlocking coils, spirals or loops.

Spiral, coil or loop types of slide fasteners are made from strips or filaments of flexible or resilient materials such as wire or plastic of oblong cross-section. The flexibility or resiliency of the fastening elements 'hasprevented successful use therewith of conventional sliders having locking means thereon.

Conventional locking sliders are generally of two types. One employs a cam means and requires considerable pressure to place it in locking position. Pressure exerted by the cam tends to deform the fastener loops and in some instances deformation may be so great as to damage the fastener loops, rendering the slide fastener inoperable.

The second general type of locking slider includes one or two pins on the tab of the slider. The pin is arranged 'so that when the slider tab is depressed, the pin will enter between the fastening elements of the stringer and lock the slider relative to the stringer. While this type of locking element does not have all of the disadvantages of the 'cam type when used with coil, spiral or loop types of fasteners, its use is not completely satisfactory for a number of reasons. For example, the pin in its closed position can dig into and damage plastic fastening elements if pressure is applied to the tab when the teeth and fastening elements are not in proper alignment. Further, as the slider is moved along the stringer by means of the tab, the pin on the tab scratches the surfaces of the fastening elements, thereby weakening them and causing rough operation of the slider. Most important, however, is the fact that when the locked stringer is stressed "in either a lateral or longitudinal manner, all of the stress is transmitted by the pin to a very small area of the filament, thereby causing severe deformation and injury to the Moreover, the locking tab has a tendency to open so that the pin type of fastener frequently comes unfastened, allowing unwanted opening of the-fastener.

In addition to the fact that the material employed with coil, spiral or loop-type fasteners is relatively soft and flexible, no given convolution of the fastener is rigidly attached to the stringer tape. Instead, the entire structure is fixed to the tape by passing a loop of thread around each convolution in a coil or spiral or around each loop in a loop type of fastener. The flexibility of this means of attachment makes it impractical for a single convolution or loop to take the stress of a pin of a pin-type locking slider by itself. It must utilize the supportderived ventional slider locking means. do notallow' such'dellec-.

'tion, withconse'quent damage to theifa'stenerelenients.

tooth does the same in the opposite direction. result is a considerable amount of friction, which assists 2,972,793 RC6 Patented Feb. 289 1961 In accordance with the present invention, a new type of fastening or locking slider for a slide fastener which avoids the disadvantages of the prior art devices is provided.

The new locking-type slider isp-articularly useful with a slide fastener having flexible fastener elements. The slider has a positioning tab, pivotally mounted on the top plate thereof. A plurality of teeth, preferably four or five in number, are attached to the tab. Apertures in the top plate are provided, allowing the teeth to pass into the space between the plates and to engage the, fastener elements when the tab is in locked position. The teeth are so arranged that the engaging surfaces of each tooth are inclined at an angle substantially matching the natural inclination of the fastener element. The length of each tooth is' arranged so that about one-third of the coil diameter is engaged when the locking tab is in place inlocked position. Furthermore, each pin is arranged to be received by the meshed fastener elements in the opening between a fastener element and the opposing tape. The arrangement is such that a slight amount of lateral compression of the fastener element in the direction of the tape to which the element is attached is obtained when the locking tab is in locking position.

The improved locking type slider of this invention, has several advantages. The inclined portion of the locking tooth and the adjustment of tooth length allow deflection of the fastener element when an excessive amount of pressure is applied tothe, slider fastener. The deflection allows the fastener element to escape permanent damage while under severe stress. At the same time, the fasteners will remain locked under the stresses of normal usage, the'lateral compression provided by the teeth firmly and positively holding the fastener from moving in either direction.

The lateral compression creates an additional friction between the side walls of the slider and the fastener elements. The tooth on the right-hand side of the slider pushes a fastener element against the guide bead and flange on the left side of the slider, and the left-hand The net in holding the slider in locked position. Longitudinal stress on the stringer merely deflects the fastener elements'and causes further congestion and pressure by the fastener elements against the beadsand confining slider.

The automatic locking feature of this invention is, of course, optional but may be taken advantage of where desired. A locking tooth is provided by shaping the tooth at the end of the slider tab nearest the fastener elements in the form of a shallow hook, the point of thehook being directed toward the island-of the slider.

Thus, the locking tooth will tend to catch readily in the fastener elements and any downward movement of the tab on the stringer will draw the tab and locking points into locking position.

An additional novel feature of this locking-type slider is the arrangement of the tab on the slider. The'tab is adapted to take any of three positions. The tab may be either fixed in the down or locking positionyfixed in a position at an angle of degrees to the stringer, or placed flat in the direction opposite the lo'ckedposition. The utility of the latter position is evidenced during "ironing of a garment having the slide'fastener attached,

in that any accidental placing of the tab in this position will not damagethe slider. The tab can be fixed many of these three positions'by virtue of the detents onthe punched-out bail on the slider body. Whenthe tabis -'at aposition '90 degrees from the stringer, one pair of detents-is-located -on the bail on'each'side of the tab. The pair of detents between the tab in this posi- .tion -and the-locked position is less difficult-to overcome than the other pair of detents. position at right angles to the stringer, mis-alignment of the slider body in normal service is prevented, and easier operation with less chance of jamming results. This is termed an anti-cocking feature, and is of considerable importance in slide fasteners having fastening elements prepared from resilient or flexible filaments.

For a better understanding of the present invention, reference may be had to the accompanying drawings in which:

Figure 1 is a view in side elevation and in section of a portion of a typical form of slider according to the present invention;

Figure 2 is a view in side elevation of a modification of Figure 1, embodying the automatic locking tooth of the present invention;

Figure 3 is a view in side elevation of the slider shown in Figures 1 and 2;

Figure 4 is a top view of the slider of Figure 3;

Figure 5 is a view, in end elevation, of the slider of Figure 3, looking toward the underside of the tab;

Figure 6 is a view in side elevation of a modification of the slider of the present invention;

Figure 7 is a top view of the slider of Figure 6;

Figure 8 is a view in cross section of a typical form of slider embodying the present invention, with the locking tab in closed or locked position;

Figure 9 is a cross section of the slider of Figure 8 taken above the view lines 9-9 and looking in the direction of the arrows;

Figure 10 is a diagrammatic section of a portion of the slider of this invention, illustrating the relation of the tab and the slider with the fastener elements, guide beads, and tape when the tab is in an open position;

Figure ll is a diagrammatic section of a portion of the slider of this invention, illustrating the relation of the locking teeth of the tab with the fastener elements, beads and tape, when the tab is in closed or locked position;

Figure 12 is a side elevation, in section, of the embodiment of Figure 10; and

Figure 13 is a side elevation in section of the embodiment of Figure 11.

The form of slider chosen for purposes of illustration is best adapted for use with a coil-type fastener, as shown in the Wahl patent, US. 2,300,442 and in the Neitlich application Serial No. 383,286, filed September 30, 1953. The locking coils therein described are formed of generally helical coils of a filament of oblong cross-section, the filament being formed of wire or a plastic such as nylon. Each coil is suitably stitched to a tape. The coils are provided with a backing bead cord on each row for engagement by the slider. Such a fastener is illustrated, for example, in Figure 9. In the coil-type fasteners, the elements 29 and 21 are the coils of the fastener and are attached to fabric tapes 22 by stitching 23 or other suitable means. Guide bead cords 24 and 25 are provided adjacent the junction of the coils 20 and 21 with the tapes.

A slider embodying the invention is best shown in Figures 3 and 6. It includes a top plate 26 and a bottom plate 27, both generally of fan shape connected at their wider ends by an island 28. The island 28 has concavely curved surfaces 29 and 30 on opposite sides thereof, for guiding the coils 20 and 21 of the fastener into and out of meshing relation. The plates 26 and 27 of the slider are provided with flanges 31 and 32 at opposite edges thereof, for engagement with the bead cords 24 and 25 to guide them and the coils 21B and 21 into and out of meshing relation. So much of the slider as has been described above is conventional. Such a slider is, however, modified in accordance with the present invention to provide a locking and mani ulating mechanism of novel type.

Thus, as shown in Figure 1, the top plate 25 of the slider has a bail 33 punched out of it so that the ends of When the tab is in a the bail 3 3 are joined with the top plate 26 but the mid portion of the bail 33 is spaced from the top plate 26 to leave an opening 34. Also, at the same time that the bail 33 is punched from the top plate as, apertures 35 and 36 are punched at either side of the bail 33 in the top plate 26 as shown in Figure 4, to provide openings in the top plate 26 communicating directly with the coils 2i) and 21 when in meshed condition within the slider.

The bail 33 and the opening 34 receive and support a tab 37 which is used to manipulate or move the slider along the coils 2t) and 21 and also to lock the coils 20 and 21 against separation. .As shown in Figure 5, the tab 37 may consist essentially of a U-shaped strip of metal or plastic material which has sides or arms 38 and 39 joined at their outer ends by means of a cross-bar 40 or the like. The opposite ends of the arms 38 and 39 have inwardly directed extensions 41 and 42 which are adapted to be rotatably received in the opening 34 of the bail 33. The arms 38 and 39 are each fitted with one or more locking teeth 43, as shown in Figures 5 and 6, and spaced apart laterally and lengthwise of the tab 37. The teeth 43 are arranged in offset fashion so that when the tab 37 is in locking position, the teeth 43 are received in the spaces 44in the meshed coils 2t? and 21. The locking teeth 43 are tapered and of such a length that when the tab 37 is depressed into locking position, the locking teeth 43 extend through opening 34 and into engagement with the coils 20 and 21 to the extent of only one-third the diameter of the coils 2t) and 21. As shown in Figures 8 and 13, the outer engaging surface 45 of each locking tooth 43 is tapered at an angle roughly corresponding to the angle at which coils 20 and 21 are disposed when the tab 37 is in locking position. In this Way, the locking teeth 43 can intercept and engage the convolutions of the coils 20 and 21 in the manner shown in Figures 8 and 13. Damage to the meshed coils by excessive pressure is avoided and at the same time a firm, positive lock is obtained due to the compression caused by the engagement of locking teeth 43 with the coils 283 and 21. Where the tab 37 is depressed onto the coils 20 and 21 directly, the coils 'will yield and allow the locking teeth to slide into the spaces 44.

As shown in Figure 2, an automatic locking slider mechanism may be provided by providing a slightly hookshaped locking tooth 46 which is the first tooth to be engaged on depression of the tab 37. When the tab 37 is in a partially unlocked position, through inadvertence or otherwise, any movement of the fastener will draw the locking point 46 and the remainder of the teeth 43 into locking position.

A preferred embodiment of this invention provides for four to five locking teeth 43 disposed on the arms 38 and 39, the teeth 43 being spaced apart laterally and lengthwise of the tab 37. Positioning of the locking teeth 43 in this manner enables easy registry of the teeth 43 with the spaces 44 in the meshed coils 2G and 21 and at the same time provides the desirable lateral compression illustrated in Figure 11. On engagement of the tab 37 in locked position, the parallel rows of locking teeth 43 cause lateral compression of the coils 2d and 21 against the beads 24 and 25 which are retained within the confining lateral flanges 31 and 32. Although the degree of compression is not sufiicient to cause damage to the meshed coils 20 and 21 or to the beads 24 and 25, the compression is suflicient to form a positive and efficient lock. The imposition of a longitudinal stress causes the coils 20 and 21 to try to escape the locking teeth 43. This merely deflects the coils 2i and 21 to cause still greater congestion and pressure and an improved lock.

The novel slider of this invention also provides a novel relation between the tab 37 and the slider body. The tab 37, as shown in Figures 6 and 7, cooperates with the shape of the bail 33 to hold itself in one of three positions. The hall ,33 has detents 47 and 48 disposed on the lock side of the bail 33 and detents 49 and 50 disposed on the opposite side of tab 37. When the tab 37 is in the locked position (Figure 8), the detents 47 and 48 tend to retain the tab 37 in its locked position. In unlocking the tab 37, the detents 47 and 48 are overcome and the tab takes a position at an angle of 90 degrees to V the top plate 26 and is maintained in this position between the detents 47 and 48 and the detents 49 and 50. 'If the user wishes, the tab 37 may be folded over into a third position without damage to the slider by overriding the detents 49 and 50. Detents 49 and 50, however, are preferably larger than detents 47 and 48, as the flat, unlocked tab position should be avoided in normal use.

When the tab 37 is in an upright position, it provides a stable handle with which to move the slider and the pinching action of the arms 38 and 39 is suflicient to maintain this position until the user intentionally changes it. This feature prevents the slider from becoming misaligned in normal service and is quite important, because the slider will operate more easily and with less chance of being jammed with foreign matter if the user can direct the slider by means of such a handle.

From the preceding description of a typical form of the invention, it will be understood that a locking-type slider which is particularly useful with coil-type fasteners and which avoids damage to the fastener by contact of the locking teeth with the coil thereof has been described. The structure of the slider is such that it serves as a safety device, permitting release of the coils when subjected to stresses which might damage them.

It will be understood that the tab 3-7 may be of different contour or configuration, and that additional locking teeth may be employed without departing from the invention. Accordingly, it will be understood that the form of the invention described herein is illustrative only and should not be considered as limiting the scope of the following claims.

I claim:

1. In a lock-type slider for slide fasteners, said slider having spaced parallel plates, an island connecting said plates adjacent one end and guide flanges at the lateral edges of said plates, the improvement comprising a bail extending lengthwise of and mounted on one plate, the bail having a transverse opening therein above the surface of the plate, a substantially U-shaped pull tab having a pair of arms joined at one end, the arms at the open end having inwardly-directed extended portions adapted to be rotatably received within the transverse opening of the bail, detent means arranged on the bail intermediate the locked and vertical positions of the tab and detent means arranged intermediate the vertical position and fully opened position of the tab, both of said detent means being adapted to be overcome by the application of pressure to the tab and to maintain the tab in a position substantially vertical to the fastener elements when said tab is placed in said vertical position.

2. A slide fastener comprising a pair of interlocking flexible filament-type fastening elements, each comprising a plurality of interconnected convolutions having spaces between at least portions of adjacent convolutions, a slider having spaced parallel plates, an island connecting said plates adjacent one end, and guide flanges at the lateral edges of said plates forming a pair of divergent channels merging into a main channel, a pull tab having one arm being laterally spaced from and in staggered I relation lengthwise of said arm to the pinvon the other arm, the pin on one arm. being engageable between the' convolutions on one of said fastener elements and the pin on the other arm being engageable between the convolutions of the other fastener element, each of said pins being adapted to engage the fastener elements while in the main channel to the extent of about one-third of the diameter of the fastener element, each of said pins having relatively inclined surfaces substantially matching the inclination of the convolutions engaged by said pins and each of said pins having a cross-sectional area at the engaged portion such that when received in the spaces between engaged convolutions in the fastener element the pins contact and urge opposing convolutions laterally toward the opposite guide flange of the slider thereby creating an area of friction and compression within the slider.

3. A slide fastener comprising a pair of interlocking flexible filament-type fastening elements, each comprising a plurality of interconnected convolutions having spaces between at least portions of adjacent convolutions, a slider having spaced parallel plates, an island connecting said plates adjacent one end, and guide flanges at the lateral edges of said plates forming a pair of divergent channels merging into a main channel, a backing bead cord on each fastening element for engagement by the slider, a pull tab having spaced-apart arms pivotally mounted on one plate, at least one pin on the end of each arm, said pin on one arm being laterally spaced from and in staggered relation lengthwise of said arm to the pin on the other arm, the pin on one am being engageable between the convolutions on one of said fastener elements and the pin on the other arm being engageable between the convolutions of the other fastener element, each of said pins being adapted to engage the fastener elements While in the main channel to the extentof about one-third of the diameter of the fastener element, each of said pins having relatively inclined surfaces substantially matching the inclination of the convolutions engaged by said pins and each of said pins having a cross-sectional area at the engaged portion such that when received in the spaces between engaged convolutions in the fastener element the pins contact and urge opposing convolutions laterally toward the opposite backing bead cord and guide flange ofthe slider thereby creating an area of friction and compression within the slider.

-4. The lock-type slider of claim 2 wherein one of said plates is provided with a bail for rotatably mounting the pull tab and wherein the bail is provided with two detent means, one of said detent means being arranged on the bail intermediate the locked and vertical positions of the tab, and the other detent means being arranged on the bail intermediate the vertical position and the fully opened position of the tab.

References Cited in the file of this patent UNITED STATES PATENTS Great Britain".. June 23, 1949

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