US3798714A

US3798714A - Flange-lock slider

Info

Publication number: US3798714A
Application number: US00254360A
Authority: US
Inventors: G Mueller
Original assignee: Textron Inc
Current assignee: Talon Inc
Priority date: 1972-05-18
Filing date: 1972-05-18
Publication date: 1974-03-26
Anticipated expiration: 1991-03-26
Also published as: FR2185031A1; LU67619A1; CA977128A; GB1397516A; FR2185031B3

Abstract

A ladder-type filamentary slide fastener has a flange-lock slider in which a single locking projection extends into the slider channel from only one of the two flanges on each side thereof whereby the slider exhibits improved locking characteristics, increased smoothness in slider operation and reduced fastener binding and wear.

Description

ljite States Patent Mueller Mar. 26, 1974 FLANGE-LOCK SLIDER 3,449,803 6/1969 Manning 244205.14 R

Z 2 2 5. 75 Inventor: Gilbert A. Mueller, St. Catharines, 6 788 H1966 Sambe'g 4/ Q R Ontario, Canada P E. B d A. l k [73] Assignee: Textr0n,lnc., Providence, RI. "man mmmer emar Gea [22] Filed: May 18, 1972 57 ABSTRACT [21] Appl No.: 254,360 1 A ladder-type filamentary slide fastener has a flange- U S 24/205 14 lock slider in which a single locking projection extends [51] 'A 19):) into the slider channel from only one of the two [58] i 74/305 14 flanges on each side thereof whereby the slider exhib- 7 h its improved locking characteristics, increased [56] References Cited smoothness in slider operation and reduced fastener binding and wear. UNITED STATES PATENTS 1,890,336 12/1932 Nodine v. 24/205.15 R 1 Claim, 3 Drawing Figures FLANGE-LOCK SLIDEIR BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to slide fasteners and, more particularly, to an improved flange-lock slider for a ladder-type filamentary fastener.

2. Description of the Prior Art In many applications for filamentary slide fasteners, such as in reversible jackets, tents, sleeping bags, and the like, it is desirable to provide the fastener slider with a pull tab on both sides so that the fastener can be opened or closed from either side of the item. This has created the need for a new type of lock for the fastener slider since conventional slider locks are generally spring biased into a locking position and are designed to cooperate with the pull tab for releasing the slider automatically. This type of locking mechanism is not readily adaptable to a double pull-tab slider since the lock must be released by either of the opposed pull tabs in order for the fastener to be effective.

The prior art, as exemplified by U.S. Pat. Nos. 3,226,788 and 3,449,803, is generally cognizant of slider locking mechanisms in which fixed projections engage the filamentary coupling elements or the stitching threads of a slide fastener whenever the fastener carrier tapes are spread apart. U.S. Pat. No. 3,226,788, for example, discloses a slide fastener having coiled filamentary coupling elements which are stitched onto one side of a pair of carrier tapes such that beads formed by the stitching will be engaged by a pair of identical locking tabs when the tapes are separated. This type of device has the obvious disadvantage of increased stitching thread wear. Also, the slider is limited to those uses in which coiled filaments are employed and are attached to one side of the tapes such that a series of protruding stitching thread beads are formed. Likewise, U.S. Pat. No. 3,449,803 discloses a fastener which has not proven to be satisfactory under all conditions of operation. In a fastener which has a locking projection extending from both flanges on each side of the slider body, the entry of one of the projections into the interstices of the filamentary coupling elements on one side of the carrier tape is often blocked by the abutment of a heel member on the other side of the tape with the other locking projection. This design coupled with the fact that the filamentary stringers are preferably constructed with a low-friction synthetic material, such as nylon, often causes the slider to slip open inadvertently. In addition, with a pair of locking projections facing each other on opposite sides of each carrier tape, the tendency exists for the filamentary stringers, and in particular the stitching threads, to become wedged between the locking tabs as the slider is moved along the fastener chain. This disadvantageous operation is further exaggerated by the fact that the fastener is normally under a force which tends to spread the tapes apart and engage the four locking projections. With four points of engagement, the slider is subject to undue binding that both impedes initial slider movement and produces rough operation thereafter.

Thus, while numerous attempts have been made in the recent past to develop an effective flange-lock slider, a simple and improved slider of this type for providing positive locking, reduced wear and increased smoothness of operation for use in a ladder-type filamentary fastener has heretofore been unavailable.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to construct a flange-lock slider for a ladder-type filamentary slide fastener including a main body member having a pair of spaced, parallel wing members, first and second pairs of opposing flanges extending respec-.

tively from opposite lateral edges of the wing members toward each other to define a Y-shaped channel for receiving the filamentary stringers, and one flange only of each pair of flanges having a locking tab projecting therefrom into the channel whereby slider movement along the fastener tapes is facilitated and the locking tabs may be positively lodged in the space between adjacent heel members of the fastener on one side of the tape when the slide fastener is spread apart.

Another object of this invention is to construct a flange-lock slider having fewer elements and improved locking and wear characteristics for use with laddertype fasteners having low-friction synthetic filamentary coupling elements.

Some of the advantages of the present invention reside in its smoothness of operation, effectiveness in locking the slider of a ladder-type fastener in place, and ability to provide positive locking action without damaging the slide fastener chain or its stitching threads.

Other objects and advantages of the present invention will become apparent from the following description of a preferred embodiment when taken in conjunction with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary plan view ofa ladder-type filamentary slide fastener having a flange-lock slider according to the present invention;

FIG. 2 is an enlarged fragmentary side elevational view of the slider of FIG. 1; and

FIG. 3 is an enlarged sectional view taken along line 3-3 of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT The present invention is embodied in a ladder-type slide fastener indicated generally at 10 in FIG. 1 including a pair of interengagable continuous filamentary stringers l2 and 112, each having a plurality of generally U-shaped

upper heel members

14, 114 and, as shown in FIGS. 2 and 3 a plurality of generally U- shaped

lower heel members

16, 116 interconnected by a plurality of

head elements

18, 118. The slide fastener 10 additionally includes a pair of

carrier tapes

20 and 120 upon which the stringers l2 and 112, respectively, are attached.

The filamentary stringers are each disposed along a longitudinal edge of one of the carrier tapes with the upper and lower heel members overlying opposite sides of the tapes. In this manner, the heel members are alternately disposed on opposite sides of each tape such that the adjacent upper heel members 14, 1 14 are separated by a space in superposition with one of the

lower heel members

16, 116 and vice versa. Filamentary stringers l2 and 112 are held in place by any suitable means such as

stitching threads

22 and 122, respectively.

A slider, indicated generally at 24, is disposed on

tapes

20 and 120 to facilitate selective opening and closing of the fastener as is well known. Slider 24 has a pair of parallel superposed

wing members

26 and 28 which are joined at their upper ends (as visualized in FIG. 1) by a generally rectangular spacing member 30 having its longer dimension aligned longitudinally of the carrier tapes and 120. Spacing member has an exterior end 32 which is formed flush with the upper edges of

wings

26 and 28 and an interior end 34 which is tapered in the plane of

tapes

20 and 120 to form an apex 36. End 34 of spacing member 30 is also tapered in a plane normal to the plane of

tapes

20 and 120 to form a V-shaped edge 38 as shown in FIG. 2. Edge 38 and apex 36 are joined by a smooth, continuous surface which acts to separate the interengaged

head elements

18 and 118 of

stringers

12 and 112 as the slider is moved downwardly along the fastener chain.

Pivotally mounted on the upper and lower surfaces of

wings

26 and 28, respectively, are two

pull tabs

40 and 42 which facilitate movement of the slider 24 along the fastener tapes from either side of the fastener 10.

Flanges

44 and 46, forming a first pair of opposing flanges, extend from one lateral edge of each

wing

26 and 28, respectively, toward each other; similarly,

flanges

48 and 50, forming a second pair of opposing flanges, extend from an opposite lateral edge of each

wing

26 and 28, respectively, toward each other.

Flanges

44, 46, 48 and 50,

wings

26 and 28 and tapered spacing member 30 cooperate to define a generally Y- shaped channel, as shown in FIG. 3, for receiving the

filamentary stringers

12 and 112 of slide fastener 10.

Formed on the upper end of each of diagonally opposed flanges 44 and is a respective one of a pair of locking tabs or

projections

52 and 54 which extend into the Y-shaped channel. It is important to note that as shown in the drawing,

flanges

46 and 48 do not carry any projecting surfaces and present a smooth surface to the filamentary stringer portions in the channel. The

locking projections

52 and 54 have a constant width which is substantially equal to the width of

flanges

44 and 50; that is, the tab dimension in the direction normal to the plane of the

carrier tapes

20 and 120 is approximately constant throughout its length and the locking projections do not curve or taper away from the tapes. The

locking projections

52 and 54 also have respective inner surface portions 53 and 55 which are relatively square and flat for engaging the filamentary heel members without distorting the same.

In operation, fastener 10 is especially well suited for use in heavy-duty applications or wherever it may be desired to have the slider operable from both sides of an item. For example, fastener 10 may be installed in a tent, reversible jacket or sleeping bag to name but a few. When installed in the desired item, slider 24 will automatically lock itself in place by the cooperative action of

locking tabs

52 and 54 and the heel members of the fastener chain. As shown, in FIG.. 3, any opening or spreading force placed on the fastener 10

causes tapes

20 and 120 to spread apart such that the filamentary stringers R2 and 112 are drawn outwardly until all of the heel members engage the walls of

flanges

44, 46, 48 and 50. Since each

upper heel member

14, 114 is superposed over a space between adjacent

lower heel members

16, 116 in the ladder-type chain and in view of the presence of only one locking projection for each lateral flange pair, it can be appreciated that the filamentary stringers are permitted to move to their extreme outermost position under any spreading force to cause the locking projections to become positively locked in the interstices of the fastener elements. It can be easily recognized from FIG. 3, that had there been a locking projection extending from flange 46 as well as from flange 44, such projection would have abutted lower heel member 16 so as to prevent the filamentary stringer 12 from moving completely out to a satisfactory position for establishing the locking engagement of projection 52 with upper heel member 14. As a result, the present construction assures complete and positive locking of the slider with both carrier tapes of the fastener l0 and, accordingly, is extremely well adapted for use with fasteners having filamentary stringers constructed of a low-friction material, such as nylon. it is also noted that because of the surface constant width surface portion 53 or 55, respectively, of each of the diagonally opposed

locking tabs

52 and 54, abutment of the tabs with the heel portions in the locking position is head-on such that substantially all of the locking or movement-resisting forces are directed longitudinally along the fastener chain. Consequently, the locking tabs do not tend to distort the heel members of the filamentary stringers out of their normal plane and thus do not produce pinching, abrasion or binding of the slider during operation as well as upon locking.

When it is desired to open the fastener 10, either pull

tab

40 or 42 may be used and a force applied in a direction to move the slider downwardly, as visualized in FIG. 1. Since each pair of opposing lateral flanges 44-46 and 48-50 contains only one locking projection, the number of locking points or points of filament engagement of slider 24 is minimized, in accordance with the present invention, while still enabling the locking of both carrier tapes. Since a minimum number oflocking points exist in slider 24, undue or excessive force need not be applied to produce initial movement ofthe slider 24 when opening the fastener. Also, the absence of opposing locking projections for each lateral flange pair minimizes the possibility of filament or stitching thread binding and wear as the slider is moved thus increasing the useful life of the fastener as well as the item to which it is attached.

Thus, the present invention provides a slide fastener having improved locking characteristics, smoother operation due to a reduction in the number of locking points, reduced abrasion and wear, and reduced binding upon initial movement of the slider to open the fastener. The present invention is therefore considered to represent a material advance in the art and has provided a practical and effective solution to a number of serious problems in this field.

Inasmuch as the present invention is subject to many variations, modifications and changes in detail, it is intended that all matter contained in the foregoing description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

l. A ladder-type filamentary slide fastener comprising a pair of carrier tapes each carrying along a longitudinal edge a filamentary stringer having a plurality of head elements interconnecting adjacent ones of a plurality of generally U-shaped heel members which are alternately disposed on opposite sides of the tape such that adjacent heel members on the same side of the tape are separated by a space in superposition with a heel member on the opposite side of the tape,

a slider having first and second spaced parallel wing members,

a first pair of opposing flanges, each flange of said first pair of opposing flanges extending respectively from a lateral edge of each of said first and second wing members toward each other on a first side of said slider,

a second pair of opposing flanges, each flange of said second pair of opposing flanges extending respectively from a lateral edge on each of said first and second wing members toward each other on a second side of said slider,

said first and second pairs of opposing flanges forming a Y-shaped channel for receiving the filamentary stringers with the heel members slidingly engaging the respective first and second pairs of flanges one flange only of each of said first and second pairs of opposing flanges having a locking tab projecting therefrom into said channel for being received into a space separating adjacent heel members when a spreading force is applied to said tapes, the other flange of each of said first and second pairs of opposing flanges having a smooth surface allowing free movement of the respective heel member on the opposite side of the tape from the space receiving said locking tab, each of said locking tabs having an inner surface portion with a constant width throughout its length substantially equal to the width of the inner surface portions of the respective flanges for engaging said heel members without distorting the filamentary stringers, and one of said locking tabs extending from a flange on the first wing member and the other of said locking tabs extending from a flange on the second wing member such that said locking tabs are disposed in a diagonally opposing relationship across said channel.

Claims

1. A ladder-type filamentary slide fastener comprising a pair of carrier tapes each carrying along a longitudinal edge a filamentary stringer having a plurality of head elements interconnecting adjacent ones of a plurality of generally Ushaped heel members which are alternately disposed on opposite sides of the tape such that adjacent heel members on the same side of the tape are separated by a space in superposition with a heel member on the opposite side of the tape, a slider having first and second spaced parallel wing members, a first pair of opposing flanges, each flange of said first pair of opposing flanges extending respectively from a lateral edge of each of said first and second wing members toward each other on a first side of said slider, a second pair of opposing flanges, each flange of said second pair of opposing flanges extending respectively from a lateral edge on each of said first and second wing members toward each other on a second side of said slider, said first and second pairs of opposing flanges forming a Yshaped channel for receiving the filamentary stringers with the heel members slidingly engaging the respective first and second pairs of flanges one flange only of each of said first and second pairs of opposing flanges having a locking tab projecting therefrom into said channel for being received into a space separating adjacent heel members when a spreading force is applied to said tapes, the other flange of each of said first and second pairs of opposing flanges having a smooth surface allowing free movement of the respective heel member on the opposite side of the tape from the space receiving said locking tab, each of said locking tabs having an inner surface portion with a constant width throughout its length substantially equal to the width of the inner surface portions of the respective flanges for engaging said heel members without distorting the filamentary stringers, and one of said locking tabs extending from a flange on the first wing member and The other of said locking tabs extending from a flange on the second wing member such that said locking tabs are disposed in a diagonally opposing relationship across said channel.