Cable tie having improved holding feature

Abstract: A bundling tie (10) for looping about plural articles includes a head (12), tail (16), and elongate strap body (14) therebetween. The head (12) and the strap body (14) include cooperative locking means (24, 26) for securing the strap in the head (12) of the bundling tie. The tail (16) of the bundling tie includes outwardly projecting tactile elements (32, 34) for enhancing the gripability of the tail (16) to facilitate pulling the strap body (14) through the head (12) of the bundling tie. The head (12) and the tail (16) also permit the removable holding of the tail (16) in the head (12) of the bundling tie prior to locking engagement of the strap body (14) with the head (12).

Description: FIELD OF INVENTION: The present invention relates generally to bundling ties for securing a group of articles. More particularly, the present invention relates to a cable tie having an improved tail design which permits the tail to be more easily gripped and permits temporary retention of the tail in the head of the cable tie. BACKGROUND OF THE INVENTION: Cable ties have long been used to bundle a variety of objects such as electrical wires or cable. Examples of such cable ties are shown in U.S. patent numbers 3,186,047, 3,486,201, 5,154,376 and 4,272,870. Each of these cable ties includes an elongate member having a head at one end, a tail at the other and a longitudinal strap body therebeween. The cable tie is used by wrapping the tie around a bundle of articles and inserting the tail through the head. The head and the body include cooperative locking elements so that when the tail is pulled tightly through the head, the locking elements secure the strap body in the head. Gripping elements are provided on one side of the tail in US-A-3 186 047 and US-A-4 272 870. Cable ties come in various shapes and sizes. Often, multiple small cable ties are employed at spaced locations longitudinally along the bundle of wires. Use in this manner presents two distinct problems. First, given the small size of the cable tie, it is difficult to grasp the tail and to securely pull it through the head. There is a tendency for the tail to slip out from between the fingers of the installer making securement around the bundle difficult. Also, when multiple small cable ties are employed, it is often necessary to loosely wrap the tie around the bundle at the spaced locations and then, in sequence, tighten each cable tie around the bundle. When using small cable ties, there is a tendency for the tail to "pop out" of the head prior to locking engagement therewith. When this occurs, it is necessary to rethread the tail through the head and possibly realign the cable ties which may have shifted prior to securement. US-A-3965538 discloses a bundling tie for wrapping around an article comprising an elongate member having a head at one end, a tail at the other end and a central strap body therebetween. The central strap body includes teeth therealong. The head includes a passage therethrough for receipt of the tail and a locking barb extending into the passage for locking engagement with the teeth of the strap body. The tail has an extending projection on one side thereof for engagement with a profile change of the head on the side of the passage opposite the barb, the tail including outwardly projecting tactile elements on the other side thereof from the projection for enhancing manual gripping of the tail, the tactile elements are on the other side of the tail from the projection and of a configuration and disposition on the tail not to engage the locking barb during receipt of the tail into the passage. The configuration in US-A-3965538 requires a change in head profile opposite the barb to provide something with which the projection can engage; there is a potential problem also that when the tail is withdrawn, the projection will tend to urge the tail towards the barb and risk jamming the tail in the head; there is no disclosure of the tail being removable from the head after engagement of the projection with the head. SUMMARY OF THE INVENTION The approach of the present invention is to locate the projection on the side of the tail facing the barb to provide releasable engagement between the projection and the barb, rather than altering the passage profile and having the projection engage the passage profile discontinuity. This aims to provide a simpler and improved solution to the problem of temporary retention of the tail. According to the invention, there is provided a bundling tie for wrapping around an article comprising an elongate member having a head at one end, a tail at the other end and a central strap body therebetween, the strap and tail each having first and second opposed planar surfaces, said central strap body including teeth therealong on said first planar surface, said head including a passage therethrough for receipt of said tail and a locking barb extending into said passage for locking engagement with said teeth of said strap body, said tail having an extending projection for releasably holding said tail in said head passage, said tail including outwardly projecting tactile elements for enhancing manual gripping of the tail, said tactile elements being separate and distinct from said extending projection and of configuration and disposition on said tail to not engage said locking barb during receipt of said tail into said passage, said projection being located on said first planar surface of the tail for engagement with the locking barb and configured to enable disengagement from said locking barb and withdrawal from said head upon application of a force to said tail in a direction opposite its insertion into said passage. Specifically shown by way of the preferred embodiment herein, the tail of the bundling tie further includes improved outwardly projecting tactile elements which enhance the gripability of the tail to facilitate pulling the tail through the head. BRIEF DESCRIPTION OF THE DRAWINGS By way of example, one embodiment of a cable tie according to the invention will now be described with reference to the accompanying drawings, in which: Figure 1 is a side plan view of an improved cable tie of the present invention. Figure 2 is an enlarged showing of a tail portion of the cable tie of Figure 1. Figure 3 is a rear plan showing of the tail of the cable tie shown in Figure 2. Figure 4 is a cross-section of the tail of the cable tie taken through the lines 3-3 of Figure 3. Figure 5 shows in section, the head of the cable tie of Figure 1 receiving the tail. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to Figure 1, a cable tie 10 of the present invention is shown. Cable tie 10 is typically an elongate molded plastic member which is used in a manner which is well known in the art, to wrap around articles or bundles of articles such as electrical wire or cable (not shown). Cable tie 10 has a head 12 at one end and a depending strap body 14 extending therefrom. The opposite end of strap body 14 includes a tail 16. Strap body 14 is typically planar shaped having first and second opposed surfaces 18 and 20. Head 12 of cable tie 10 includes a central passage 22 therethrough, which as will be more fully described hereinbelow, accommodates tail 16 and strap body 14 therein. The cable tie 10 shown in Figure 1 is of the type having an integrally molded barb 24 formed in the head portion which extends into passage 22. Cable tie 10 also includes a longitudinally extending plurality of teeth 26 along surface 20 of strap body 14. Barb 24 includes one or more barb teeth 28 which engage strap teeth 26 to lock the strap body 14 into head 12 after it is coiled around a bundle of articles. The locking operation of strap body 14 with head 12 is well known in the cable tie art. Additionally, while a cable tie having an integrally molded barb 24 and a strap body 14 with strap teeth 26 is shown, the present invention may also be employed with a cable tie having a embedded metallic barb in head 12 and a smooth strap body 14. In conventional operation, tail 16 is wrapped around a bundle of articles and inserted through the passage 22 of head 12. As the strap is pulled through the passage, strap teeth 26 engage barb teeth 28 and in a ratchet-like action, secure the strap body 14 in head 12. Tail 16 may be continually pulled to "snug-up" cable tie 10 around the bundle of articles. Interaction of the strap teeth 26 and barb teeth 26 is such that withdrawal of the strap body through head 12 is prevented. Referring additionally to Figures 2 and 3, tail 16 of cable tie 10 is shown in more detail. The tail 16 includes a tapered, pointed end extent 30 which facilitates insertion of the tail 16 through the passage 22 of head 12. Tail 16 further includes a plurality of first tactile gripping elements 32 extending from surface 20 thereof. Gripping elements 32 are extended, rounded elements which are positioned at spaced apart locations along either longitudinal edge of surface 20. As shown in Figure 3, first gripping elements 32 are provided in transversely spaced pairs along the length of tail 16. A central portion 21 of tail 16, between each pair of first gripping elements 32, remains flat to permit the tail to be inserted through passage 22 and over barb teeth 28. First gripping elements 32 therefore are not in interference with the barb teeth 28 as the tail 16 is being inserted through passage 22. The raised nature of gripping elements 32 permit the tail 16 to be firmly grasped so that a superior grip is provided when the tail is being pulled through passage 22 of head 12. The non-smooth surface presented by gripping elements 32 helps to prevent slippage of tail 16 from between the fingers of the installer. This is a especially beneficial when employing small cable ties. Additionally, surface 18 of tail 16 also includes second gripping elements 34 spaced longitudinally therealong. Second gripping element 34 are in the shape of sharp lances which extend fully transversely across surface 18 of tail 16. As surface 18 is positioned opposite barb teeth 28 during insertion, there is no interference between second gripping elements 34 and barb teeth 28. Therefore, second gripping elements 34 may extend fully across tail 16. As shown in Figures 2 and 3, first gripping elements 32 are slightly rounded and extend outwardly greater a distance than second gripping elements 34. In order to permit tail 16 to easily pass through passage 22, second gripping elements 34 are designed not to extend outwardly as far as first gripping elements 32. Thus, a sharper ridge is provided on second gripping element 34 to facilitate secure grasping. As first gripping elements 32 extend further outwardly, they need not have as sharp a projection as the increased extension provides sufficient gripping surface. While tail 16 of the present invention may include either shaped gripping elements on either side of tail 16, it has been found that superior results and better tactile gripping is achieved by providing first rounded type gripping elements 32 on surface 20 of tail 16 and providing sharper shorter gripping elements 34 on opposed surface 18. Referring specifically now to Figures 3 and 4, tail 16 further includes a centrally disposed projection 40 extending from surface 20. Projection 40 is positioned between longitudinally extending transversely spaced first gripping elements 32 midway along central portion 21. Projection 40 is positioned so as to engage barb teeth 28 upon insertion of tail 16 into passage 22. As shown in Figure 4, projection 40 is wedge shaped having a inclined surface 42 and an adjacent abutment surface 44. Projection 40 is designed to engage barb teeth 28 upon insertion of tail 16 through passage 22 to prevent tail 16 from inadvertently dislodging from head 12 prior to the locking engagement of strap teeth 26 with barb teeth 28. Referring to Figure 5, it can be seen that as strap 16 is inserted into passage 22 in the direction of arrow A, incline surface 42 of projection 40 will permit the continued insertion of tail 16 therethrough. The barb teeth 28 will easily ride over inclined surface 42. A raised barb tooth 28a is designed to engage abutment surface 44 (Figure 4) after projection 40 has passed over barb teeth 28. Tail 16 will be prevented from inadvertently backing out of passage 22 by the engagement of raised tooth 28a with abutment surface 44 of projection 40. Engagement of raised tooth 28a with abutment surface 40 is a relatively light securement which, if necessary, can be overcome by pulling tail 16 through aperture 22 in the direction opposite that of arrow A. This is advantageous in situations where it becomes necessary to unwrap cable tie 10 prior to locking engagement. However, the engagement of raised tooth 28a with abutment surface 44 is sufficient to prevent inadvertent backing out of tail 16 from passage 22. Various changes to the foregoing described and shown Structures would now be evident to those skilled in the art. Accordingly, the particularly disclosed scope of the invention is set forth in the following claims.

Claims: A bundling tie (10) for wrapping around an article comprising: an elongate member having a head (12) at one end, a tail (16) at the other end and a central strap body (14) therebetween, the strap and tail each having first and second opposed planar surfaces (20, 18); said central strap body including teeth (26) therealong on said first planar surface (20); said head (12) including a passage (22) therethrough for receipt of said tail (16) and a locking barb (24) extending into said passage for locking engagement with said teeth (26) of said strap body; said tail (16) having an extending projection (40) for releasably holding said tail (16) in said head passage (22), said tail including outwardly projecting tactile elements (32) for enhancing manual gripping of the tail, said tactile elements (32) being separate and distinct from said extending projection (40) and of configuration and disposition on said tail to not engage said locking barb (24) during receipt of said tail (16) into passage (22), said projection (40) being located on said first planar surface (20) of the tail (16) for engagement with the locking barb (24) and configured to enable disengagement from said locking barb (24) and withdrawal from said head (12) upon application of a force to said tail (16) in a direction opposite its insertion into said passage (22). A bundling tie of claim 1 wherein said tactile elements (32) extend from said first planar surface (20) of said tail (16). A bundling tie of claim 1 or claim 2 wherein said tactile elements (32) extend longitudinally in spaced apart pairs along said tail (16) and wherein said extending projection (40) is positioned between said spaced apart pairs. A bundling tie of any one of claims 1 to 3, wherein said projection (40) is located on said first planar surface (20) at a position longitudinally spaced from said teeth (26). A bundling tie of any one of claims 1 to 4, wherein said projection (40) and said locking barb (24) are complementarily configured to be in relatively light securement which is overcome upon application of said force. A bundling tie of any one of claims 1 to 5, wherein said projection (40) is of configuration different from the configuration of said strap body teeth (26). A bundling tie of any one of claims 1 to 6, wherein each of said tactile elements (32) comprises a rounded surface. A bundling tie of any one of claims 1 to 7, wherein said tail includes a plurality of spaced tactile elements (34) extending outwardly from said second planar surface (20). A bundling tie of any one of claims 1 to 9 wherein the projection (40) has ramp surfaces for engagement with the barb (24) on entry and exit of the tail, the ramp surface on exit being steeper in slope than the ramp surface on entry.

Inventors: FORTSCH WILLIAM A, FORTSCH, WILLIAM A.
Applicants: THOMAS & BETTS CORP, THOMAS & BETTS CORPORATION (A TENNESSEE CORPORATION)
Application year: 1993
Main classification: B65D63
IPC codes: F16B2, B65D63