Twist off cable tie fastener

An improved twist off cable tie fastener having an elongate flexible strap defining a plurality of parallel adjacent transverse teeth. First end portion of elongate strap is tapered to a rounded tip for insertion through a channel defined in a dimensionally larger head portion carried at opposing end of the elongate strap. At least one angulated tooth carried by a flexing arm within the channel irremovably engages with the transverse teeth defined in the elongate strap. The head portion has two opposing and spaced apart wings to facilitate grasping and rotation by a user about a minor transverse axis of the elongate strap. Partial rotation of the wings concentrates strap fracturing forces at a position immediately adjacent to the head portion causing destruction of the cable tie fastener and allowing removal thereof without tools.

RELATED APPLICATIONS

There are no other patent applications related hereto heretofore filed in the United States of America or in any other country.

BACKGROUND OF INVENTION

Field of Invention

This invention relates to clasps and closures and more particularly to single use fasteners having a head portion defining a slot at one end of an elongate strap that loops over and irremovably engages in the slot.

Background and Description of Prior Art

Fasteners of the instant type are commonly referred to as “cable ties” and are well-known for fastening items together such as container latches, bundles of wire and groupings of flexible tubular members, Typically the fastener is threaded through adjacent aligned holes defined in portions of a container that move distally from one another when the container is opened, or the fastener is extended circumferentially around the bundle of wires or groupings of items to secure the wires or groupings of items in proximity to one another.

Generally, cable ties have an elongate strap that is tapered at one end portion. Opposite the tapered end portion is a dimensionally larger head portion defining a slot through which the tapered end portion of the elongate strap may be inserted. A resiliently displaceable pawl is carried within the slot and the pawl engages with one of a plurality of transverse grooves defined in the elongate strap.

Cable tie type fasteners are typically single use items. Once the elongate strap is inserted through the slot and the pawl has engaged with the parallel transverse grooves, the elongate strap cannot be withdrawn from the slot without breaking the pawl, breaking the elongate strap or otherwise physically destroying the cable tie. Once the cable tie has been broken, it cannot be repaired or re-affixed.

The inability to remove a fastened cable tie without physically or functionally destroying the cable tie is both a desirable feature and a drawback.

Because of theft single use nature, cable ties are commonly used in apparatus that require security, such as the transport of money, pharmaceuticals and other valuable commodities. When a container of the commodity is filled, closed and thereafter secured with a cable tie, it can reasonably be assumed that if the container, and in-place cable tie, are undisturbed when the container is later opened, and that the container and contents have not been tampered with, Conversely, if the container or the cable tie have been broken, it can reasonably be assumed that the original contents of the container have been tampered with and are no longer in the same condition and perhaps same quantity, as they were when the cable tie was originally secured to the container.

In the pharmaceutical industry, cable ties are used to securely close pharmaceutical tote boxes. A tote box arriving with the cable tie broken or damaged can be rejected or at a minimum closely inspected. In other instances it is desirable to have a strong and secure fastener that may be quickly engaged/fastened when necessary and also quickly and easily removed, for example in outdoor activities such as camping where securing items together is necessary, such as joining tarps together or securing items to tree branches. Further, in law enforcement activities such fasteners may be used as restraints for persons being detained. In both such examples of use, the strong and secure fastener is required, but being able to quickly and easily remove/destroy the fastener is also necessary.

By the same token, one of the drawbacks of cable ties is that they are difficult to break. Cutting the cable tie with a wire cutter or knife poses a risk of unintentionally damaging the item being secured and requires use of a tool. Breaking the cable tie by inserting an elongate rigid object, such as a screwdriver, through the looped elongate strap and twisting the inserted object to break the cable tie is even more likely to damage the item secured by the cable tie.

There are known “tear away” cable ties designed for easy removal. Known tear away cable ties have a planar rectilinear tag adjacent the head portion and define a “scored” or “weakened” area between the tag and the head portion. Pulling on the rectilinear tag portion tears the cable tie at the “scored/weakened” area detaching the head portion from the strap portion without use of a tool or cutting device. Unfortunately, shearing forces such as those used to intentionally break known “tear away” cable ties may be inadvertently applied to the cable tie if the rectilinear tag is inadvertently caught between two surfaces that move relative to one another, such as a top and a bottom or adjacent sides of adjacent containers being transported in a vehicle. Any movement wherein one container moves along and across an adjacent container may provide the necessary shearing motion to break known tear away cable ties. Further, known “tear away” cable ties with rectilinear tags have sharp edges and corners, they are not aesthetically pleasing, they are difficult to package in bundles because the rectilinear tags “catch” on one another and they can be difficult to manufacturer.

What is needed is a durable secure cable tie type fastener that cannot be removed without destroying the cable tie, but can be intentionally removed without resorting to took and without damaging the item being secured. The cable tie must be easy to use, not subject to unintentional breakage, aesthetically pleasing and easy to manufacture and package.

Our improved twist off cable tie fastener addresses various of these drawbacks by providing a product that is strong and secure and is less likely to be inadvertently and unintentionally broken, but can also be broken without use of took when desired. When broken, the fact the cable tie has been broken is un-mistakenly identifiable.

Our invention is an improved twist off cable tie type fastener comprising an elongate strap of flexible yet strong plastic, preferably polypropylene, that defines a plurality of parallel adjacent transverse teeth in the elongate strap. One end portion of the elongate strap is tapered to a rounded tip to ease insertion through a through channel defined in a head portion integrally carried at the end of the elongate strap opposite the tapered tip.

The through channel carries an angled flexing arm having plural angular teeth that cooperatively engage with the transverse teeth defined in the elongate strap. The angulated teeth carried by the flexing arm are configured to prevent the elongate strap from being withdrawn from the through channel once inserted therethrough and a channel frame around the through channel prevents insertion of took that might be used to tamper with the flexing arm.

The head portion defining the through channel is generally rectilinear in peripheral configuration and structurally carries two opposing spaced apart planar wings on its side portions with the two wings oriented parallel to an axis of the through channel and perpendicular to the elongate strap. This orientation causes any excess length of the elongate strap that is drawn through the medial channel when the fastener is in use to extend outwardly between the two spaced apart wings which allows space saving and allows use of the fastener in locations with limited space.

A notch may be formed in the elongate strap immediately adjacent the head portion to ensure fracturing occurs at a predetermined location. The notch does not negatively affect the axial or tensile strength of the cable tie.

The wings carried by the head portion facilitate grasping and twisting of the head portion by a user. The twisting action which is along a minor transverse axis of the elongate strap and perpendicular to a longitudinal axis of the elongate strap concentrates breaking forces on the elongate strap immediately adjacent the head portion. The perpendicular rotation of the wings breaks the cable tie allowing the cable tie's removal without tools and without damaging the item to which the cable tie was fastened. Further, limited rotational movement of the wings, of less than approximately one full 360 degree rotation is sufficient to fracture the cable tie fastener, and more preferably, less than approximately 180 degrees of rotation is sufficient to fracture the cable tie fastener, and still even more preferably, approximately 90 degrees of rotation is sufficient to fracture the cable tie fastener.

SUMMARY

A first aspect of the present invention relates to an improved twist off cable tie fastener having an elongate strap with opposing side portions and tapered to a rounded tip at one end, the elongate strap defining plural parallel adjacent transverse teeth defined in one side portion and further having a head portion integrally interconnected with the elongate strap opposite the rounded tip, the head portion having a channel frame with a first side and an opposing second side and defining a medial channel extending from the first side to the second side, the channel frame further having a first wing at one side portion and a second wing at an opposing side portion and wherein the first wing and the second wing are oriented parallel to an axis of the medial channel and perpendicular to a longitudinal axis of the elongate strap, the medial channel carrying an angled flexing arm therein for engagement with the transverse teeth defined in the elongate strap, and wherein the rounded tip and a portion of the length of the elongate strap is inserted in and passed through the medial channel in only one direction and cannot removed therefrom, and destruction and removal of the cable tie fastener occurs by partial rotational motion of the first and second wings about a non-coaxially aligned axis of the elongate strap.

Still another aspect of the present invention relates to an improved twist off cable tie fastener having an elongate strap with opposing side portions and tapered to a rounded tip at one end, the elongate strap defining plural parallel adjacent transverse teeth defined in one side portion and further having a head portion integrally interconnected with the elongate strap opposite the rounded tip, the head portion having a channel frame with a first side and an opposing second side and defining a medial channel extending from the first side to the second side, the channel frame further having a first wing at one side portion and a second wing at an opposing side portion and wherein the first wing and the second wing are oriented parallel to an axis of the medial channel and perpendicular to a longitudinal axis of the elongate strap, the medial channel carrying an angled flexing arm therein for engagement with the transverse teeth defined in the elongate strap, and wherein the rounded tip and a portion of the length of the elongate strap is inserted in and passed through the medial channel in only one direction and cannot removed therefrom, and destruction and removal of the fastener occurs by partial rotational motion of the first and second wings about a non-longitudinally aligned axis of the elongate strap.

Still another aspect of the present invention relates to an improved twist off cable tie fastener having an elongate strap with opposing side portions and tapered to a rounded tip at one end, the elongate strap defining plural parallel adjacent transverse teeth defined in one side portion and further having a head portion integrally interconnected with the elongate strap opposite the rounded tip, the head portion having a channel frame with a first side and an opposing second side and defining a medial channel extending from the first side to the second side, the channel frame further having a first wing at one side portion and a second wing at an opposing side portion and wherein the first wing and the second wing are oriented parallel to an axis of the medial channel and perpendicular to a longitudinal axis of the elongate strap, the medial channel carrying an angled flexing arm therein for engagement with the transverse teeth defined in the elongate strap and wherein the rounded tip and a portion of the length of the elongate strap, is inserted in and passed through the medial channel in only one direction and cannot removed therefrom, and destruction and removal of the fastener occurs by partial rotational motion of the first and second wings about a minor transverse axis of the elongate strap.

Still another aspect of the present invention relates to an improved twist off cable tie fastener having an elongate strap with a first side portion, a second side portion and tapered to a rounded tip at one end portion, the elongate trap defining plural parallel adjacent transverse teeth defined in the first side portion, and further having a head portion integrally interconnected with the elongate strap opposite the rounded tip, the head portion having a channel frame with a first side and an opposing second side and defining a medial channel extending from the first side to the second side, the channel frame further having a first wing at one side portion and a second wing at an opposing side portion, the medial channel positioned between the first wing and the second wing, and wherein the first wing and the second wing are oriented parallel to an axis of the medial channel and perpendicular to a longitudinal axis of the elongate strap, the medial channel carrying therein an angled flexing arm having plural teeth on an end portion distal from the channel frame for engagement with the transverse teeth defined in the elongate strap, and wherein the rounded tip and a portion of the length of the elongate strap is inserted in and passed through the medial channel in only one direction and cannot removed therefrom, and destruction and removal of the fastener occurs by simultaneous rotation of the first wing and the second wing about a minor transverse axis of the elongate strap which concentrates breaking forces on the elongate strap immediately adjacent to the head portion causing destruction of the fastener and allowing removal thereof without tools.

A still further aspect is to provide an improved twist off cable tie fastener that is of new and novel design, of rugged and durable nature, of simple and economic manufacture and one that is otherwise well suited to the uses and purposes for which it is intended.

Other and further aspects of our invention will appear from the following specification and accompanying drawings which form a part hereof. In carrying out the objects of our invention it is to be understood that its structures and features are susceptible to change in design and arrangement with only one preferred and practical embodiment of the best known mode being illustrated in the accompanying drawings and specified as is required.

DESCRIPTION OF PREFERRED EMBODIMENT

An improved twist off cable tie fastener generally provides an elongate strap10having a head portion11with a channel frame44defining a medial through channel43. The elongate strap10and head portion11are integrally formed as a single unit, such as by injection molding, and is preferably formed of polypropylene, but may also be formed of nylon, polyethylene and other flexible resiliently deformable plastics and/or thermoplastics.

The elongate strap10carries the head portion11at one end and is tapered to a rounded tip15at the opposing end portion to ease insertion into and through the medial channel43. The elongate strap10has a first side19and an opposing second side20defined by a first elongate edge portion17and a second elongate edge portion18.

The first side19is generally planar and smooth to ease movement of the elongate strap10through the channel43. A plurality of parallel adjacent teeth25are defined in the second side20of the elongate strap10and extend transversely partially across the second side20from a position spaced apart from the first elongate edge portion17to a position spaced apart from the second elongate edge portion18, leaving a toothless border26adjacent the first elongate edge17and a toothless border26adjacent the second elongate edge18. The teeth25are defined in the second side20from a position spaced apart from the rounded tip15to a position spaced apart from the head portion11.

As shown inFIG. 1, each transverse tooth25defined in the elongate strap10has a crest25a, a trough25b, a ramp portion25cand a relief25dand collectively form a plurality of transverse teeth25along the elongate strap10that may easily pass, only in one direction, through the channel43while frictionally engaging with an angulated flexing arm46carried within the channel43. Each of the plurality of transverse teeth25defined in the elongate strap10are dimensionally similar to a distal end portion of the flexing arm46which carries strap engaging teeth47,48.

The head portion11is somewhat “wingnut” in shape having a first wing35at one lateral edge and a second wing36at an opposing lateral edge. Each wing35,36is integrally formed with the head portion11to extend laterally outwardly from the channel frame44which defines the medial channel43extending transversely through the head11portion from a first side27to a second side28. The first and second wings35,36respectively, are each aligned with an axis51of the channel43so that the two wings35,36are each oriented generally perpendicularly to the first and second elongate sides17,18respectively of the elongate strap10and extend in a direction toward the first side27of the head portion11. This orientation of the first and second wings35,36respectively, causes any forces generated by rotational movement (FIG. 7) of the wings35,36to be along a minor transverse axis51of the elongate strap10. This orientation, which causes the rounded tip portion15of the elongate strap10to extend outwardly between the two wings35,36when the improved fastener is in use, also allows the improved fastener to be used in locations having limited space because all portions that extend outwardly (away from the item being secured) are oriented along the same plane. As noted previously, the elongate strap10is integrally formed with and is connected to the head portion11channel frame44at a peripheral edge portion37generally medially between the first wing35and second wing36. A notch23may be defined in the elongate strap10immediately adjacent the head portion11creating a localized area having reduced resistance to applied rotational motion along with the minor transverse axis.

As shown inFIGS. 1, 2, 3, 5, 6, 7 and 8the axis51which is defined by the medial channel43passes through the medial channel43extending between the first side27and the second side28of the channel frame44. The axis51is oriented perpendicular to the length of the elongate strap10and is aligned parallel to the opposing planar surfaces of the two opposing wings35,36carried on each opposing lateral side of the channel frame44as is shown inFIGS. 1 and 3. The orientation of the medial channel44and the two opposing wings35,36as shown inFIGS. 6 and 7causes the rounded tip15of the elongate strap10opposite the channel frame44to extend outwardly from the channel frame44between the two opposing wings35,36and coaxially with the axis51of the medial channel43when the instant improved twist-off cable tie fastener is in use. (FIG. 6) Further still, this alignment and orientation positions the two opposing wings35,36so that twisting/torqueing forces exerted on the wings35,36by the user focuses shearing forces on the elongate strap10immediately adjacent the connection of the elongate strap10to the channel frame44which allows destruction/fracture of the elongate strap10immediately adjacent the channel frame44and allowing tool-less removal of the instant improved twist-off cable tie fastener.

The channel frame44is generally rectilinear and defines the through channel43into which the rounded tip portion15of the elongate strap10is inserted. The side-to-side dimension of the channel43is only slightly greater than the distance between the first elongate edge17and the second elongate edge18along a major transverse axis53of the elongate strap10, and the channel43is sized and configured to allow passage of the elongate strap10therethrough with limited friction while maintaining positional rigidity therebetween to prevent tampering with a flexing arm46.

The flexing arm46is carried within the channel43proximate the elongate strap10. As shown inFIG. 1, the flexing arm46is angulated into the channel43extending away from the second side28of the channel frame44and toward the first side27of the channel frame44at an angle50which is established in the manufacturing process. Angle50pre-loads the flexing arm46to enhance frictional engagement with the teeth25defined in the elongate strap10when the flexing arm46is deflected by the elongate strap10being inserted through the channel43. The angle50and resiliency of the flexing arm46positionally bias the elongate strap10into continuous direct frictional engagement with an opposing surface of the channel43opposite the flexing are46. Angle50is preferably between approximately 21 degrees and 35 degrees relative to an adjacent inner surface of the channel frame44(SeeFIG. 1), and more preferably the angle50is between approximately 24 degrees and 32 degrees relative to the adjacent inner surface of the channel frame44, and optimally the angle50is 28.04 degrees relative to the adjacent inner surface of the channel frame44.

End portion of the flexing arm4$, opposite the connection to the channel frame44defines a first arm tooth47, and in the preferred embodiment, an adjacent parallel second arm tooth48. The flexing arm teeth47,48are sized and configured to securely engage with the transverse teeth25defined in the second side20of the elongate strap10. The toothless borders26of the elongate strap10slide through the channel43in laterally outer areas of the channel43that are laterally outward of the flexing arm46to further increase positional engagement of the elongate strap10within the channel43and to further reduce the likelihood of successful tampering with the flexing arm46.

The “wingnut” configuration of the head portion11including the opposing spaced apart wings35,36facilitate grasping and rotation of the head portion11by a user. The rotational motion of the wings35,36concentrates the rotational movement about the minor transverse axis51of the elongate strap10which concentrates breaking forces on the elongate strap10immediately adjacent the head portion11. The rotational motion of the head portion11fractures the improved twist off cable tie fastener facilitating destruction of and removal of the improved cable tie fastener without use of tools and without damaging any item the improved twist off cable tie fastener might be securing.

Having described the structure of our improved twist off cable tie fastener, its operation may be understood.

The improved twist off cable tie fastener is positioned about items (not shown) to be secured, or items (not shown) to be secured together such as a grouping of wires (not shown), or a portion of a toy displayed within a “display box”. The elongate strap10is extended about the items (not shown) and the rounded tip portion15is looped there-about and then inserted into the channel43entering the channel43from the second side28of the head portion11and exiting the first side27of the head portion11immediately between the first wing35and the second wing36.

The rounded tip portion15is grasped by the user, and drawn at least partially through the channel43so that some portion of the elongate strap10defining teeth25passes through the channel43. As the elongate strap10passes through the channel43the teeth47,48, respectively carried by the flexing arm46engage with the teeth25defined in the second side20of the elongate strap10. The angulation50of the flexing arm46relative to the elongate strap10, and the resiliency of the material forming the improved cable tie fastener allows the flexing arm46to bend toward the first side of the head27effectively allowing the crests25aof the teeth25to pass over the flexing arm teeth47,48until the elongate strap10is snug about the item(s) (not shown) being secured.

The retentive memory of the flexing arm46causes the teeth47,48to engage with the teeth25defined in the second side20of the elongate strap10when the elongate strap10is no longer being drawn through the channel43. If the user attempts to withdraw the elongate strap10from the channel43in the reverse direction, the configuration and angulation of the flexing arm46and the flexing arm teeth47,48which are engaged with the elongate strap teeth25prevent the withdrawal of the elongate strap10from the channel43.

To remove the fastener, the user grasps the head portion11and applies a rotational force to the head portion11by means of rotating the two wings35,36simultaneously in a clockwise direction, or simultaneously in a counterclockwise direction about the axis51of the through channel43. The twisting of the head portion11concentrates fracturing forces at the interconnection of the elongate strap10and head portion11. The preferred polypropylene material of the improved cable tie fastener is resistant to tensive forces and to shearing forces but is less resistant to rotational forces. The rotational force applied by the twisting of the head portion11causes the improved twist off cable tie fastener to break allowing the cable tie's destruction and subsequent removal without tools. Once the cable tie fastener has been destroyed, it cannot be reaffixed.

The foregoing description of our invention is necessarily of a detailed nature so that a specific embodiment of a best mode may be set forth as is required, but it is to be understood that various modifications of details, and rearrangement, substitution and multiplication of parts may be resorted to without departing from its spirit, essence or scope.

Having thusly described our invention, what we desire to protect by Letters Patent, and