CA1057483A - Cable tie and method for making same - Google Patents

Cable tie and method for making same

Info

Publication number
CA1057483A
CA1057483A CA229,175A CA229175A CA1057483A CA 1057483 A CA1057483 A CA 1057483A CA 229175 A CA229175 A CA 229175A CA 1057483 A CA1057483 A CA 1057483A
Authority
CA
Canada
Prior art keywords
strap
tie
strap portion
aperture
free end
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
CA229,175A
Other languages
French (fr)
Inventor
Jack E. Caveney
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panduit Corp
Original Assignee
Panduit Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Panduit Corp filed Critical Panduit Corp
Application granted granted Critical
Publication of CA1057483A publication Critical patent/CA1057483A/en
Expired legal-status Critical Current

Links

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16LPIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L3/00Supports for pipes, cables or protective tubing, e.g. hangers, holders, clamps, cleats, clips, brackets
    • F16L3/22Supports for pipes, cables or protective tubing, e.g. hangers, holders, clamps, cleats, clips, brackets specially adapted for supporting a number of parallel pipes at intervals
    • F16L3/23Supports for pipes, cables or protective tubing, e.g. hangers, holders, clamps, cleats, clips, brackets specially adapted for supporting a number of parallel pipes at intervals for a bundle of pipes or a plurality of pipes placed side by side in contact with each other
    • F16L3/233Supports for pipes, cables or protective tubing, e.g. hangers, holders, clamps, cleats, clips, brackets specially adapted for supporting a number of parallel pipes at intervals for a bundle of pipes or a plurality of pipes placed side by side in contact with each other by means of a flexible band
    • F16L3/2338Supports for pipes, cables or protective tubing, e.g. hangers, holders, clamps, cleats, clips, brackets specially adapted for supporting a number of parallel pipes at intervals for a bundle of pipes or a plurality of pipes placed side by side in contact with each other by means of a flexible band having at least one metal locking barb
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B65CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65DCONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
    • B65D63/00Flexible elongated elements, e.g. straps, for bundling or supporting articles
    • B65D63/10Non-metallic straps, tapes, or bands; Filamentary elements, e.g. strings, threads or wires; Joints between ends thereof
    • B65D63/1018Joints produced by application of integral securing members, e.g. buckles, wedges, tongue and slot, locking head and teeth or the like
    • B65D63/1027Joints produced by application of integral securing members, e.g. buckles, wedges, tongue and slot, locking head and teeth or the like the integral securing member being formed as a female and male locking member, e.g. locking head and locking teeth, or the like
    • B65D63/1036Joints produced by application of integral securing members, e.g. buckles, wedges, tongue and slot, locking head and teeth or the like the integral securing member being formed as a female and male locking member, e.g. locking head and locking teeth, or the like the female locking member being provided with at least one metal barb
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16GBELTS, CABLES, OR ROPES, PREDOMINANTLY USED FOR DRIVING PURPOSES; CHAINS; FITTINGS PREDOMINANTLY USED THEREFOR
    • F16G11/00Means for fastening cables or ropes to one another or to other objects; Caps or sleeves for fixing on cables or ropes
    • F16G11/10Quick-acting fastenings; Clamps holding in one direction only
    • F16G11/101Quick-acting fastenings; Clamps holding in one direction only deforming the cable by moving a part of the fastener

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Package Frames And Binding Bands (AREA)
  • Buckles (AREA)

Abstract

ABSTRACT OF THE DISCLOSURE
The present invention provides a self-locking cable tie for forming a plurality of wires or the like into a bundle, said tie comprising:
a stretched elongate flexible strap portion for posi-tioning about said wires or the like and made of a plastic ma-terial whose molecules can be stretch-oriented;
a head portion extending from one end of said strap portion, having a strap entrance face and a strap exit face, and having a generally transverse aperture extending from said strap entrance face to said strap exit face for receiving the distal end of said strap portion, said aperture having a pre-determined strap path therethrough; and locking means made of non-plstic material and carried by said head portion and having a free end portion extending into said strap path and toward said strap exit face, said free end portion and said strap portion each having an engageable com-ponent for causing such a high localized stress concentration in said strap portion that said strap portion is pierced by said free end portion, one of said engageable components compri-sing at least one protuberance sharply pointed relative to the other engageable component, said protuberance being positioned to engage said other engageable component prior to engagement of other parts of said one engageable component with said other engageable component whereby upon insertion of the distal end of the strap portion into said aperture from said strap entrance face, the strap portion interferes with and deflects said free end portion to permit tightening of said tie around said wires or the like and whereby said engageable components cause the localized stress concentration in said strap portion upon appli-cation of withdrawal forces to enable said free end portion to pierce said strap portion and prevent retrograde movement of said strap portion.

Description

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CABLE TIB AND METHOD FOR MAKING S~IE
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Background of the Invention This invention relates to cable ties and more particularly to self-locking cable ties molded from a stretch~
oriented plastic material. ;
Heretofore cable ties have been molded to the dimensions of the end product. In order for such ties to ~-meet tensile strength requirements, the strap portions of such ties had a relatively large cross-sectional area. This large area was required because the molecules of the molded thermoplastic material were relatively unoriented and, accordingly, the material lacked the strength of material which was stretch-oriented. Additionally, difficulties were encountered in molding ties having a long strap portion because increased heat and pressure were required to completely fill the mold cavity. The increased heat may tend to cause degradation of the thermoplastic material while the increased ~`
pressure could cause the mold to pump open (flash). Examples of prior art molded cable ties are sho~m in U.S. Patent Nos.
3,~186,047 and 3,660,869. I
Straps of stretched thermoplastic material have been proposed for bundling packages or a plurality of objects and for attaching tags and buttons to clothing. Examples of such ~; ~
straps are shown in U.S. Patent Nos. 3,444,597 and 3,447,207. 1~`
Such prior art straps have usually not been self-locking and required separate crimp connectors for application to an over-lapped portion of the strap. ~ -.: . ~,.
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One self-locking stretched strap has been proposed which includes an elongate strap portion having a plurality of transverse rwlgs and a head portion having an integral locking pawl which is biased to a position between consecutive rungs. Of course, it has only locking positions corresponding to the rungs. As it is not infinitely adjustable, in certain applications it only provides a loose bundle or an overly tight bundle. Such a ladder construction also requires a long head to ensure there is a rung to engage the pawl upon cutof-f of the strap tail flush with the head. A long head is also needed because sufficient space is required between consecutive ~
rungs to allow pawl movement therebetween. Of course, longi- ~ -tudinal stretching of such a strap causes only the sides to increase in tensile strength because the rungs are not stretched significantly. Since the rungs do not contribute to the tensile strength of the material, such a structure results in an inefficient use of material. Also, this type of strap does not provide a uniform pressure on the bundle because of the alternate rungs and apertures and because the~sides are harder than the rungs.~ Nonuniform pressure on the bundle could cause an undesirable stress concentration on the bundled wires.
Reference may be made to U.S. Patent No. 3,766,608.
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Summary of the Invention ", Among the several objects of the present invention ~
may be noted the provision of an improved cable tie; the ;
provision of such a cable tie which has high tensile strength with reduced cross-sectional area and which, accordingly, requires much less material for fabrication; the provision of - ~ .
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"' .' ' ' - ' ' , ., , ` ' ~ LD~9 such a cable tie whic]l is self-locking and infinitely adjustable, the provision of such a tie which provides generally uniform pressure on the bundled wires and provides reduced bundle weight; the provision of such a tie which has a low profile head, and the provision of such a cable tie which is reliable in use, has long service life, and is simple and economical to manufacture. Other objects and features of the invention will be in part pointed out here-inafter, and in part apparent.
Briefly, a self-locking cable tie of the present invention for forming a plurality of wires into a bundle comprises a stretched elongate flexible strap portion for positioning about the wires, an integral head portion extending from one end of the strap portion, and a locking means carried ;~
by the head portion. The strap portion is made of a plastic material comprising stretch-oriented molecules. The head portion includes a generally transverse aperture for receiving ~`
the strap portion and extends between the head portion strap entrance and strap exit faces. The aperture includes a pre- ~ ~;
determined strap path therethrough. The locking means is non-integral with the head portion and has a free end portion extending into the strap path and toward the strap exit face.
The free end portion and the strap portion have engagable components for causing a localized stress concentration in the strap portion. Accordingly, insertion of the distal end of the strap portion into the aperture from the strap entrance face causes the strap portion to interfere with and deflect the free end portion to permit tightening of the tie. Upon application of withdrawal forces, the engagable components cause the localized stress concentration to enable the free .
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end portion to pierce the strap portion and prevent retrograde movement thereof.
A method of making a cable tie from a molded part made of a plastic material comprising stretch-orientable molecules includes several steps. The molded part includes an elongate strap portion and an integral head portion extending from the strap portion having a strap entrance face, a strap exit -face, and a generally transverse aperture extending between the faces. The st~ps of the metho~ include:
a) stretching the strap portion in its longitudinal direction until its molecular structure is oriented; and b) securely inserting locking means which has a free end portion into the head portion to provide an inter-ference fit between the strap portion and the free end portion when ~he cable tie is assembled, the last-mentioned two portions having engagable components for causing a localized stress concentration in the strap portion upon application of with- ~;
drawal forces to the strap portion so that the free end por~ion can pierce the strap portion and prevent retrograde movement ~
thereof. '-Brief Description of the Drawings FIG. 1 is a plan of a molded part before stretching and cutting to -form, in part, a cable tie of the present invention;
FIG. 2 is a -front elevational view of the part of FIG. l;
FIG. 3 is a sectional view generally on line 3-3 of FIG. 2;
FIG. 4 is a sectional view generally on line 4-4 of FIG. 2;

FIG. S is a side elevational view of a head portion of tlle part of FIG. l;
FIG. 6 is a plan of the cable tie formed from the part of FIG. 1 after stretching and cutting and after a locking means has been inse*ted into the head portion of the tie;
FIG. 7 is a front elevational view of the cable tie of FIG. 6;
FIG. 8 is a sectional view generally on line 8-8 of FIG. 7;
FIG. 9 is a sectional view of an alternate strap portion which has an arcuate cross section;
FIG. 10 is a sectional view generally on line 10-10 of FIG. 7;
FIG. 11 is an end view of the head portion of the cable tie of FIG. 6;
FIG. 12 is a sectional view generally on line 12-12 :
of FIG. 6;
FIG. 13 is similar to FIG. 12 and shows the locking means being deflected upon insertion of a strap portion into .
the head portion;
FIG. 14 is similar to FIG. 12 and shows the locking :
means engaging the strap portion upon attempted strap withdrawal; ~ :
FIG. 15 is a plan of the head portion of the cable tie of FIG. 6 with the strap portion inserted; and ;` .~.
FIG. 16 is a sectional view of the cable tie of :~
FIG. 6 positioned around a bundle of wires. ;~
Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

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Description of the Preferred Embodiment Referring to FIGS. 1-5, an as-molded part is generally indicated at reference numeral 19. As will appear hereinafter, part 19 is stretched, cut, and provided with a locking means 21 to form a self-locking high strength cable tie 23, shown in FIGS. 6-8 and 10-11, of the present invention, for forming a plurality of wires 25, see FIG. 16, into a bundle which, usually has a generally circular cross section. Cable tie 23 comprises an elongate flexible strap portion 27 made of a thermoplastic material, such an nylon, comprising stretch-orien-ted molecules;
and an integral head portion 29 extending from one end of strap portion 27, having a strap entrance face 31 and a strap exit face 33, and having a generally transverse aperture 35 from face 31 to face 33 for receiving the distal end of strap portion 27.
Aperture 35 includes a generally V-shaped strap entry section extending from strap entrance face 31 and a generally flat ~
strap exit section extending from strap exit face 33. The pur- ;
poses of these sections will appear hereinafter. Cable tie 23 also includes an elongate tail 37 extending from strap portion : ~ .
27. Tail 37 is preferably bent out of the longitùdinal direction of strap portion 27 towards strap entrance face 31. Components ~ `
of part 19, see FIG. 1, corresponding to components of cable tie 23 except for stretching and/or cutting are designated by a prime.
As-molded nylon parts have relatively unoriented molecules. Stretching of the part causes orientation of the ~ `
molecular structure in the direction of the stretch. After stretching, although the part is reduced in cross section, it has high tensile strength and breaking strength. That is, . . . .

stretching causes the tensile strength of the material to increase. Also the stretching causes hardening of the material.
As shown in FIGS. 1 and 2, as-molded part 19 includes a pulling lug 39 extending in opposite directions from tail 37'.
Before stretching, the cross section of strap portion 27' may be significantly larger than the cross section of aperture 35.
Part 19 is stretched between lug 39 and the junction of strap portion 27' and head portion 29 until the molecular structure of the nylon in the strap portion is oriented and, preferably, ~ i until the cross section thereof is substantially identical to that of the strap entry section of aperture 35. The length of the strap portion 27' may be increased three times, for ~, .
example, during the stretching operation. Thus, a long cable tie need not be molded to its final dimensions, but a relatively short tie can be molded and stretched to the desired length . :~
thereby significantly reducing the ~amount of material used, overcoming the problems attendant to~molding a relatively long .,,.:. .
tie, and reducing the weight of the bundle. Tail 37' has an indentation 41' extending longitudinally therealong. The purpose of the indentation will appear hereinafter. ^
Aperture 35 lncludes a predetermlned strap path :~
therethrough. This strap path is that portion of the aperture 35 occupied by strap portion 27 when the cable tie 23 is disposed about a wire bundle as shown in FIG. 16. Of course, for the particular embodiment shown wherein strap portion 27 and the strap entry section of aperture 35 are of substantially identical cross section, the strap path includes substantially the entire strap entry section.

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Locking means 21 is non-integral with head portion 29 and is shown in FIGS. 6 and 11-16 as being constituted by a metallic barb or tongue having one end portion 43 thereof securely embedded in a reinforcing rib portion 45 of head portion 29 adjacent strap entrance face 31. Locking barb 21 extends therefrom toward aperture 35 and strap exit face 33 at an acute angle relative to the longitudinal direction of strap portion 27. Barb 21 includes a free end portion 47 having at least one pointed protuberance 49 extending into the strap path of aperture 35 for engaging strap portion 27.
Of course, a point is defined by the intersection of at least three planes. Each of the pointed protuberances 49 shown in FIG. 11 is defined by the intersection of the three planes in which lie: (a) the beveled surface at the distal end of free end portion 47, ~b) the facing side of the locking means shown in FIG. 11, and ~c) either of the right or left edges, ~ -as viewed in FIG. 11 of the locking means. It will be ~ ~ ~
appreciated that the distal end of free end portion 47 could ---be comprised of more than a single surface.
More particularly, a strap portion 27 is non-flat and is shown as having a generally V-shaped cross section, see FIG. 8, and has a pair of diverging legs lying in more than a single plane. Each of the legs has a longitudinally extending side edge 51. An alternate strap portion 27a, see FIG. 9, has an arcuate cross section and side edges 51a. ~ ;
The strap portion as shown in either of FIGS. 8 and 9, comprises a non-flat cross section whereby an imaginary ; plane as indicated at 56 in FIGS. 8 and 9, disposed parallel to the longitudinal axis of the strap portion and contacting .
~ ~. ''' ,' ' ~ ' but not intersecting the surface of that part of the cross section adjacent the strap portion edges 41, 41a, is spaced from a substantial portion o-f the sur~ace between the edges and nearest the plane 56. It will be appreciated that stipules or bumps could be utilized with the present invention `
to prevent the tie from slipping on the bundle. Accordingly, the relationship between the plane 56 and the cross sections of FIGS. 8 and 9 ignores the nonuniform effect on the cross sections due to any such stipules. The strap portion has an inner surface that IS adapted to be disposed towards the bundle ;~
after the assembly of the cable tie around the bundle~and an ;;~
outer surface adapted to be disposed away from the bundle after the assembly of the cable tie around the bundle. The inner and outer surfaces are joined by the edge surfaces 51, 51a, and as shown in FIGS. 8 and 9, each of the inner and outer surfaces is substantially non-flat. When cable tie 23 is positioned around a wire bundle as shown in FIG. 16, side edges 51 ; ;~
initially engage wires 25 to restrain sliding of the tie along ~
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the bundle. As tie 23 is tightened, strap portion 27 tends to -flatten so that the tie exerts generally uniform pressure on the bundled wires. The cross-sectional non-flat shape of strap portions 27, 27a, provide the strap portion with greater column strength than a flat strap portion thus facilitating threading around a bundle, insertion of the strap through the aperture and pushing of the strap into locking engagement with the barb. It will be appreciated that the strap is normally inserted into the aperture such that it is bent in a direction opposite to the direction that it is bent in threading around the bundle. With a V-shaped cross section, for example, the g ,......... . . . . . . ..
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~ 3 column strength of the strap portion is greater when the strap is bent with the apex of the "V" on the inside of the bend than when the strap is bent with tlle apex on the outside of the bend. Accorrlingly, maximum threading force can be applied without collapsing the pushed strap if the legs of the "V" are oriented so that they extend toward the bundle when the strap is installed. It will be appreciated that the non-flat cross section of the cable tie of the present invention could be utilized with unstretched cable ties that are either used in the as-molded condition or used after increasing the tensile strength and hardness by an alternative method, e.g. irradiation.
The strap entry section of aperture 35 is also shown as being V-shaped and has a pair of legs generally ~ ;
symmetrical about a plane through the longitudinal axis of -strap portion 27. The legs of the strap entry section extend toward strap portion 27. Locking barb 21 is generally rectangular and generally symmetrical about the plane through ~`~
the longitudinal axis of strap portion 27 with its free end 47 beveled, having a pair of pointed protuberances or pro-jections 49 extending into the strap projection path of aperture 35. Pointed protuberances 49 are constituted by corners of the free end portion 47 of barb 21. One pro-tuberance extends foremost into each leg of aperture 35.
The generally flat strap exit section of aperture 35 allows the strap portion to flatten as when the leading part of the strap portion is cut off flush with head portion 29.
The free end portion 47 of barb 21 and strap portion ~
27 can be considered to each have an engagable component for -' .
. .

causing a localized stress concentration in the strap portion ~
so that upon application of withdrawal forces, the free end ~;
portion 47 can pierce strap portion 27 and prevent retrograde movement thereof. The engagable components for causing a localized stress concentration include pointed protuberances 49 and that part of strap portion 27 engaged by the protuberances 49. As best shown in FIG. 15, the free end portion of barb 21 terminates in a line edge having its end points define the protuberances 49. The end points project into the strap path farther than the line edge between the end points whereby ~ ;
point contact between the barb and the strap portion to be ,~
engaged is ensured. Providing such engagable components is highly desirable to ensure positive locking of the stretched cable tie. As indicated above, stretching of the strap portion causes it to harden as well as to increase in tensile and ~ ;
breaking strength. If a flat hardened strap portion were engaged by a barb line edge, application of withdrawal forces -to the strap portion could cause it to slide along the barb line edge due to lower localized stress concentration.
However, if the strap portion is engaged by a pointed protuberance of the barb, application of withdrawal forces, as will appear hereinafter, causes the pointed protuberance to gouge or pierce the hardened strap portion due to the higher localized stress concentration thereby to securely hold it from retrograde movement relative to the head portion.
A rect~ngular barb having a line edge is relatively easy to manufacture. Accordingly, it will be appreciated that with the desire to utilize such a barb, the preferred embodiment -~
of the present invention provides a dual function in increasing ,.. -.... .. ~ , ,::
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the column strength of the strap and ensuring point contact with a rectangular barb. Although a strap portion having a `
V-slaped cross section is shown used in conjunction with a rectangular barb because a cable tie having these features is relatively easy to manufacture, many locking means - strap portion variations are envisioned as having engagable com- -ponents for causing such a high localized stress concentration in the strap portion that it is pierced by the locking means.
These include a generally flat strap portion for engagement by a barb in the shape of one or more spikes and a generally flat strap portion having appendages such as stipules or one or more longitudinally extending ribs for engagement by a barb line edge, in addition to other non-flat strap con-figurations.
As best shown in FIGS. 11 and 12, head portlon 2g has a trio of slots adjoining aperture 35. A first slot 52 `~
extends from adjacent barb end portion 43 towards strap exit face 33 to permit deflection of barb end portion ~7 toward the strap exit face upon insertion of strap portion 27 into aperture 35. A second slot 53 is generally aligned with a ,~;
slot 52 and extends oppositely of strap portion 27 along strap exit face 33. It will be appreciated that both slots 52 and 53 facilitate insertion of barb 21 into head portion 29. A final slot 55 is generally V-shaped and extends away from strap portion 27 along strap entrance face 31 to facilitate threading of tail 37 and to provide a nest for that section of strap portion 27 adjacent aperture 35 when cable tie 23 is disposed around a wire bundle.
Tapered tail 37 facilitates threading of strap portion 27 into aperture 35. As indicated above, tail 37 has ' ...... . . . .
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a longitudinally extending indentation or slot 41. Slot 41 receives pointed protuberances 49 so that tail 37 can be inserted into aperture 35 without interference of barb 21.
That portion of tail 37 extending from strap exit ~ace 33 can conveniently be used as a grip for completion of tightening the tie around a wire bundle.
Operation of cable tie 23 is as follows: Strap ~
portion 27 is positioned about the wires 25 to be bundled, ;
and tapered tail 37 is inserted into aperture 35. When tie 23 is tightened around the bundle, strap portion 27 interferes with and deflects pointed protuberances 49 and barb end portion 47 toward strap exit face 33 as is shown in FIG. 13. It will be appreciated that during tightening, the protuberances 49 will tend to scratch the surface of strap portion 27. After the tie has been tightened around the bundle, if withdrawal ; forces are applied to strap portion 27, pointed protuberances ~ ;
49 deflect toward strap entrance face 31 until they securely engage strap portion 27 by further piercing or gouging, see ~
FIGS. 14 and 15, thereby to positively prevent retrograde ~;
movement of the hardened strap portion 27.
A method of making a high strength cable tie 23 from a molded part 19 of thermoplastic material comprising stretch-orientable molecules includes several steps. The molded part has an elongate flexible strap portion 27' and ;~
an integral head portion 29 extending from one end of the strap portion. Head portion 29 includes a strap entrance face 31, a strap exit face 33, and a generally transverse ~
aperture 35 extending between the faces. Aperture 35 includes ~`
a predetermined strap projection path therethrough, and part '~
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19 also includes a tail 37' extending from strap portion 27'.
The method includes the following non-sequential steps:
stretching the strap portion in its longitudinal direction until its molecular structure is oriented; and securely inserting locking means 21 which has a free end portion 47 into head portion 29 to provide an inter-ference fit between the strap portion and the free end portion, the last-mentioned two portions each having an engagable com-ponent for causing a localized stress concentration in the strap portion upon application of withdrawal forces to the strap portion to enable the free end portion 47 to pierce the strap portion and prevent retrograde movement thereof.
This method also includes~ the further step of ;
removing the distal end of tail 37, preferably by taper -cutting to facilitate threading of strap portion 27 into aperture 35. This last-mentioned step is to be performed after stretching the strap portion.
Of course, many sizes of cable ties can be made using the method described above. For example,i strap portion 27 of part 19 could be an exemplary 2 inches long and the length of strap portion 27 o~ cable tie 23 could be, for example, 5 inches. The stretching step of the method could be performed, for example, with the strap portion at a temper- ~ ;
ature of approximately 125 degrees centigrade and at a stretching rate of one inch per second.
In view of the above, it will be seen that the several objects of the invention are achieved and other ;;
advantageous results attained.

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constructions without departing from the scope of the invention, it is intended that all matter contained in the `~
above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

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Claims (13)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A self-locking cable tie for forming a plurality of wires or the like into a bundle, said tie comprising:
a stretched elongate flexible strap portion for positioning about said wires or the like and made of a plastic material whose molecules can be stretch-oriented;
a head portion extending from one end of said strap portion, having a strap entrance face and a strap exit face, and having a generally transverse aperture extending from said strap entrance face to said strap exit face for receiving the distal end of said strap portion, said aperture having a predetermined strap path therethrough; and locking means made of non-plastic material and carried by said head portion and having a free end portion extending into said strap path and toward said strap exit face, said free end portion and said strap portion each having an engageable component for causing such a high localized stress concentration in said strap portion that said strap portion is pierced by said free end portion, one of said engageable components comprising at least one protuberance sharply pointed relative to the other engageable component, said protuberance being positioned to engage said other engageable component prior to engagement of other parts of said one engageable component with said other engageable component whereby upon insertion of the distal end of the strap portion into said aperture from said strap entrance face, the strap portion interferes with and deflects said free end portion to permit tightening of said tie around said wires or the like and whereby said engageable components cause the localized stress concentration in said strap portion upon application of withdrawal forces to enable said free end portion to pierce said strap portion and prevent retrograde movement of said strap portion.
2. A tie as set forth in Claim 1, wherein said head portion and said strap portion are integral.
3. A tie as set forth in Claim 2, wherein said engageable components for causing a localized stress concentration include at least one pointed protuberance on said free end portion and that part of the strap portion engaged by said pointed protuberance when the strap portion is disposed in said aperture.
4. A tie as set forth in Claim 2, wherein said free end portion includes a pointed protuberance which extends foremost into said strap path.
5. A cable tie as set forth in Claim 3, wherein said locking means comprises a second end portion securely embedded in said head portion and wherein said head portion has a slot adjoining said aperture and extending from adjacent said second end portion towards said strap exit face to permit deflection of said pointed protuberance out of said strap path.
6. A tie as set forth in Claim 2, wherein said strap portion has a V-shaped cross section.
7. A tie as set forth in Claim 5, wherein said aperture is generally symmetrical about a plane through the longitudinal axis of the strap portion and wherein said aperture includes a strap entry section extending from said strap entrance face, said strap entry section including a V-shaped portion with the legs thereof extending toward said strap portion and wherein said free end portion of the locking means has a pair of pointed protuberances extending into said strap path.
8. A tie as set forth in Claim 7, wherein said locking means is a generally rectangular metallic barb which is generally symmetrical about said plane through the longitudinal axis and wherein each of said protuberances extends into one leg of said strap entry section with each pointed protuberance being constituted by a corner of said barb.
9. A tie as set forth in Claim 8, wherein the V-shaped portion of said strap entry section and said strap portion having substantially identical cross sections.
10. A tie as set forth in Claim 1, wherein said aperture includes a generally flat strap exit portion extending from said strap exit face.
11. A tie as set forth in Claim 3, wherein said tie further comprises an elongate tail extending from said strap portion, said tail having a tapered end to facilitate insertion of said tail into said aperture.
12. A tie as set forth in Claim 11, wherein said tail has a longitudinally extending indentation for reception of said pointed protuberance so that said tail can be inserted into said aperture without substantial interference with said barb.
13. A tie as set forth in Claim 2, wherein said strap portion has an arcuate cross section.
CA229,175A 1974-08-05 1975-06-12 Cable tie and method for making same Expired CA1057483A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US49501274A 1974-08-05 1974-08-05

Publications (1)

Publication Number Publication Date
CA1057483A true CA1057483A (en) 1979-07-03

Family

ID=23966886

Family Applications (1)

Application Number Title Priority Date Filing Date
CA229,175A Expired CA1057483A (en) 1974-08-05 1975-06-12 Cable tie and method for making same

Country Status (7)

Country Link
JP (1) JPS5119694A (en)
CA (1) CA1057483A (en)
DE (1) DE2534778A1 (en)
FR (1) FR2281523A1 (en)
GB (1) GB1519301A (en)
IT (1) IT1040422B (en)
SE (1) SE7508753L (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL7608350A (en) * 1976-07-28 1978-01-31 Philips Nv DRIVEWORK.
DE4004044A1 (en) * 1990-02-10 1991-08-14 Daimler Benz Ag DEVICE FOR VENTILATING OR DRAINING VEHICLE PARTS
DE19758329A1 (en) 1997-12-31 1999-07-01 Gamaggio Schaefer Michael cable ties
US11268635B2 (en) * 2018-12-28 2022-03-08 Commscope Technologies Llc Devices and methods for holding cables

Also Published As

Publication number Publication date
GB1519301A (en) 1978-07-26
JPS5119694A (en) 1976-02-17
SE7508753L (en) 1976-02-06
DE2534778A1 (en) 1976-02-19
FR2281523B1 (en) 1980-11-07
FR2281523A1 (en) 1976-03-05
IT1040422B (en) 1979-12-20

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