Cable tie

A cable tie with a cellulosic fiber cord and angled metal blade achieves strong locking and tamper evidence, addressing environmental concerns and usability issues.

EP4656548A1Pending Publication Date: 2025-12-03EVLR INT AB
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Patent Information

Application Number
EP2024178620
Authority / Receiving Office
EP · EP
Patent Type
Applications
Current Assignee / Owner
Filing Date
2024-05-28
Publication Date
2025-12-03

AI Technical Summary

Technical Problem

Conventional cable ties pose environmental hazards due to their plastic composition and can entangle or be swallowed by animals, while lacking usability and tamper evidence.

Method used

A cable tie with a cord made of cellulosic fibers, a locking head with a specific diameter-to-gap ratio, and a metal blade angled at 47°-62°, allowing easy insertion and strong locking, using biodegradable materials.

Benefits of technology

The cable tie provides a strong, non-releasable, and tamper-evident solution with reduced environmental impact, improving usability and handling.

✦ Generated by Eureka AI based on patent content.

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Abstract

A cable tie (100) comprising: - a cord (101) having a first end (102), a second end (103), and a diameter (d), the cord comprising cellulosic fibers, and - a locking head (104) fixedly attached to the first end (102), said locking head (104) being adapted to receive the second end (103) and retain the cable tie (100) in a closed loop configuration, wherein the locking head (104) defines a wall (105) that encircles a passage (106) having an inlet (107), an outlet (108) and a central axis (110) extending between the inlet (107) and the outlet (108), and comprises a blade (109) that extends into the passage (106) for engaging the cord (101) and which is arranged to allow displacement of the cord (101) in a first direction towards the outlet (108) while preventing displacement of the cord (101) in a second direction towards the inlet (107), wherein the blade (109) comprises a first end (109a) fixed to a first wall portion (105a) of the wall (105), and a second end (109b) defining a smallest distance (h) between the blade (109) and a second wall portion (105b) of the wall (105), the second wall portion (105b) being disposed at a side of the passage (105) opposite to that of the first wall portion (105a), with respect to the central axis (110), and wherein a ratio (r) of the diameter (d) of the cord to the smallest distance (h) is 1.62-2.05.
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Description

TECHNICAL FIELD

[0001] The present disclosure relates to the field of cable ties, in particular environmentally friendly and tamper evident cable ties.BACKGROUND

[0002] Cable ties (also referred to as zip ties or plastic straps) have long been used to secure cables and other articles together.

[0003] Cable ties are used in large quantities and many of them eventually end up in the environment after use and present a danger for animals that can get entangled or swallow them. Further, the commercially available cable ties are typically formed from plastic materials having large carbon footprint.

[0004] WO2022216202A1 discloses a cable tie comprising a cord comprising cellulosic fibers and a locking head fixedly attached to the cord, said locking head being adapted to receive the second end and retain the cable tie in a closed loop configuration wherein said locking head defines a walls that encircles a passage having an inlet and an outlet and comprises a metal blade that extends into the passage for engaging the cord and which is arranged to allow displacement of the cord in a first direction towards the outlet while preventing displacement of the cord in a second direction towards the inlet.

[0005] To be regarded as an easy-to-use alternative to conventional plastic cable ties, the cable tie should preferably provide a high enough locking force for allowing it to be used in a variety of applications, while at the same time being easy to handle.SUMMARY

[0006] The present inventors have realized that the size and configuration of the cord in relation to the locking head may impact the strength of the cable tie as well as its usability.

[0007] An objective of the present disclosure is to provide a cable tie of reduced environmental impact. Another objective is to provide a cable tie that is strong, non-releasable and tamper evident. A further objective is to provide a cable tie with improved usability.

[0008] To meet the first objective, a cable tie comprising a cord of cellulosic fibers is provided. To meet the second and third objectives, a ratio between the diameter of the cord and a smallest distance between a free end of a locking blade and an inner wall of a passage through the locking head, that is the gap in which the cord is to be locked, is chosen so as to achieve a strong locking force between the cord and the locking head, while requiring a low enough force for inserting the cord. By providing a cord which requires a low enough force for inserting the cord into the locking head, the usability of the cable tie is improved. At the same time, a cable with high enough locking force to be seen as a viable option to conventional cable ties is achieved.

[0009] Accordingly, the present disclosure provides a cable tie comprising: a cord having a first end, a second end, and a diameter, the cord comprising cellulosic fibers, and a locking head fixedly attached to the first end, said locking head being adapted to receive the second end and retain the cable tie in a closed loop configuration, wherein the locking head defines a wall that encircles a passage having an inlet, an outlet and a central axis extending between the inlet and the outlet, and comprises a blade that extends into the passage for engaging the cord and which is arranged to allow displacement of the cord in a first direction towards the outlet while preventing displacement of the cord in a second direction towards the inlet, wherein the blade comprises a first end fixed to a first wall portion of the wall, and a second end defining a smallest distance between the blade and a second wall portion of the wall, the second wall portion being disposed at a side of the passage opposite to that of the first wall portion, with respect to the central axis, and wherein a ratio of the diameter of the cord to the smallest distance is 1.62-2.05.

[0010] A ratio of the diameter of the cord to the smallest distance of 1.62-2.05 has been found to be small enough to allow the cord to be pushed and pulled through the gap without too much effort, while also providing a tamper-evident cable tie.

[0011] One reason that the cord may be pushed and pulled through the passage even when the diameter d of the cord is larger than the distance h, is that the cord comprising cellulosic fibers has a certain flexibility in the radial direction, allowing it to deform under the force exerted onto the cord by the blade, as the cord is pulled through the passage.

[0012] Furthermore, the blade may be arranged to have a certain resilience, allowing it to flex or move in the direction of the outlet during pushing / pulling of the cord through the passage as the cord is pushed / pulled through the locking head. Thus, the force required for tying and tightening the cable tie may be reduced.

[0013] Since the wall(s) encircles the passage, lateral movements of the cord in the passage are prevented, which facilitates the non-releasable tie.

[0014] In an embodiment, the ratio of the diameter to the smallest distance is 1.67-2.00, such as 1.71-1.95, such as 1.77-1.91.

[0015] In an embodiment, an angle between the direction of the extension of the blade and the central axis is 47°-62°, such as 50°-59°, such as 52°-57°.

[0016] By arranging the blade at an angle, insertion of the cord into the locking head may be facilitated, while at the same time increasing the locking force. The blade may be allowed to move and / or flex to a certain degree when being subjected to a force in a direction from the outlet and towards the inlet of the passage. Such an angle has thus been found to facilitate a strong tie and still allow insertion of the second end into the passage.

[0017] In an embodiment, the diameter of the cord is 1.0-8.0 mm, such as 1.5-5.0 mm, such as 1.75-2.10 mm, such as 1.80-2.00 mm.

[0018] This diameter of the cord has been shown to provide a versatile cable tie which is strong enough for the most common applications, while not being over-dimensioned. For example, the cable tie may be used in applications where space is limited, whereby a larger diameter would be unsuitable. However, in some applications, a larger or smaller diameter of the cord may be preferred.

[0019] In an embodiment, the smallest distance is 0.60-1.20 mm.

[0020] In an embodiment, the smallest distance is 0.90-1.15 mm, such as 0.95-1.15 mm, such as 0.75-0.95 mm. This embodiment is of particularly suitable when the diameter of the cord is 1.75-2.10 mm, such as 1.80-2.00 mm.

[0021] In an embodiment, the diameter is defined as the mean value of at least 10 diameter values measured at different points distributed along the length of the cord. As discussed below, the cord may be flattened at the second end. If so, the flattened part is excluded from the diameter measurement(s). A vernier caliper may be used for the diameter measurement(s).

[0022] When the at least 10 diameter values have been measured, a coefficient of variation can be calculated. In an embodiment, the coefficient of variation is less than 5%.

[0023] In an embodiment, the cord is formed from hemp or paper.

[0024] In contrast to conventional plastic straps, there is no need form "slots" or "pockets" in such a cord to facilitate locking.

[0025] In an embodiment, the cord comprises a paper strip twisted along its length. Thereby, a cord with high strength and few surface deviations may be provided, thus improving the usability of the cable tie.

[0026] The paper strip may for example be made of a Kraft paper. Thereby, a strong and durable cord may be provided from a commonly available, and environmentally friendly, material.

[0027] In an embodiment, the blade is a metal blade.

[0028] A metal blade has been shown to efficiently prevent the cord from being pulled back out from the passage. The use of such a blade may be especially beneficial for a cord in accordance with the present disclosure, as the cord comprising cellulosic fibers is resilient enough in a radial direction to allow for the cord to be gripped by the blade, while still being durable enough to prevent tearing, even when the blade is a flat metal blade.

[0029] In an embodiment, the stretch at break of the cord is 2.0%-6.0% such as 2.5%-4.0%, when measured according to ISO 2062:1993.

[0030] In an embodiment, the cord is flattened at the second end.

[0031] The flattened second end may facilitate manual insertion into and through the passage. Such a flattened second end may further be provided with grooves. Such grooves improve the grip when pulling the cord through the passage. The direction of the extension of the grooves is preferably substantially perpendicular to the longitudinal direction of the cord. The thickness of the flattened second end may for example be 0.7-1.3 mm, such as 0.9-1.0 mm.

[0032] The thickness of the flattened second end typically varies depending on the diameter of the cord. Furthermore, a ratio of the thickness of the flattened second end to the diameter of the cord maybe 0.37-0.54.

[0033] The diameter d may be defined as the mean value of at least 10 diameter values measured at different points distributed along the length of the cord 101. Alternatively and / or additionally the diameter d may be defined as the mean value of a larger number of diameter values, such as at least 100 diameter values, measured on a plurality of different cable ties 100 from the same batch.

[0034] In an embodiment, the locking head comprises a body of a biodegradable material, such as a bio composite of a biodegradable and / or renewable polymer and an organic fiber material.

[0035] Thus, a more environmentally friendly cable tie may be achieved as compared to conventional locking heads being produced from fossil-based plastic materials.

[0036] In an embodiment, the inlet of the passage is funnel-shaped. Thereby, insertion of the second end into the inlet of the passage may be facilitated, thus increasing the usability of the cable tie.BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 is a cross-sectional side view of an embodiment of a cable tie according to the present disclosure. Figure 2 is a front view from the of a cable tie according to the present disclosure, as seen from the inlet of the passage. DETAILED DESCRIPTION

[0038] With reference to figure 1, an embodiment of a cable tie 100 of the present disclosure is described.

[0039] The cable tie 100 comprises a cord 101 having a first 102 and a second 103 end. The cord 101 comprises cellulosic fibers, e.g. in the form of a paper. Preferably, the cord is formed by twisting a paper strip along its length. The paper and the forming technique are preferably selected such that high tensile strength and a certain stretchability is obtained (e.g. a stretch at break value of 2%-5%). The diameter d of the cord 101 may be from 1.75 to 2.10 cm. A cord of such a diameter formed by a twisted paper strip may have a tensile strength (ISO 2062:1993) above 15 kg. It should be understood that the cord 101 may also have a smaller or larger diameter d. For example the diameter of the cord 101 maybe from 1.0 mm and up to 8.0 mm, depending on the intended use of the cable tie 100.

[0040] The cable ties 100 further comprises a locking head 104 fixedly attached to the first end 102 of the cord 101. The fixation is preferably achieved by over-molding the first end 102 with a thermoplastic material that forms a body portion of the locking head 104.

[0041] The locking head 104 is adapted to receive the second end 103 and retain the cable tie 100 in a closed loop configuration.

[0042] The locking head 104 defines a wall 105 that encircles a passage 106. Alternatively, the locking head defines a plurality of walls that jointly encircles a passage 106. In either case, the wall(s) prevent(s) substantial lateral movement of the cord 101 when received in the passage 106.

[0043] The passage 106 has an inlet 107 and an outlet 108. A central axis 110 extends between the inlet 107 and the outlet 108. The cord 101 is arranged to be inserted into the passage 105 in a direction parallel to the central axis 110.

[0044] The inlet 107 may be funnel-shaped, such as trumpet-shaped, to facilitate manual insertion of the second end 103 into the passage 106. To further facilitate the manual insertion, the second end 103 may be flattened.

[0045] In one embodiment, the material of the cord 101 is waxed paper, which protects the machines used for producing the cable tie by preventing abrasion. Furthermore, the waxed paper may facilitate flattening of the second end 103, sincewhen the cord is formed from waxed paper, no heating is necessary in a pressing operation used to form the flattened second end. The tool used for such a pressing operation may have (a) contact surface(s) provided with ridges to form the above-mentioned grooves in the flattened second end 103.

[0046] The locking head 104 further comprises a blade 109 that extends into the passage 106 for engaging the cord 101 after receival thereof. The arrangement of the blade 109 is such that displacement of the received cord 101 in a first direction towards the outlet 108 is allowed (meaning that the loop formed when the second end 103 is received can be tightened) while displacement of the cord 101 in the opposite direction, i.e. a second direction towards the inlet 107, is prevented (meaning that the tie cannot be released without excessive force or destruction). The blade 109 is preferably arranged at an angle α to the central axis 110, the angle α between the direction of the extension of the blade 109 and a central axis 110 preferably being 47°-62°, more preferably 50°-59°, most preferably 52°-57°.

[0047] The blade 109 may be a metal blade. For example, the blade 109 may be form from stainless steel, e.g. EN 1.4310.

[0048] The blade 109 has a longitudinal extension between a first end 109a and a second end 109b. The blade 109 is typically rectangular, the first and second ends 109a, 109b forming the short ends of the rectangle.

[0049] The first end 109a of the blade 109 is fixed to a first wall portion 105a the body portion of the locking head 104. The first end 109b typically become fixed to the first wall portion 105a by over-molding with a thermoplastic material forming the body portion of the locking head 104. Hence, the first end 102 of the cord 101 and the first end 109a of the metal blade 109 may, during production, become embedded in the same over-molding step. However, in other embodiments, the blade 109 may be arranged at a side opposite to the second end 102 of the cord, with respect to the central axis 110.

[0050] The second end 109b is a free end arranged within the passage 106, and is configured to engage the cord 110 when inserted into the passage 106. The second end 109b is arranged at a distance from a second wall portion 105b arranged at a side opposite to the side of the first wall portion 105a, with respect to the central axis 110. The second end 109b thus defines a smallest distance h from the blade 109 to the second wall portion 105b. As seen in Fig. 1, the smallest distance h is typically the distance between the second end 109b and the second wall portion 105b as measured in a direction perpendicular to the extension of the central axis 110 and, as more apparent from fig. 2, in a direction perpendicular to an axis extending along a width w of the blade.

[0051] The smallest distance h may for example be from 0.9-1.5 mm. However, other distances may also be used, depending on the intended use of the cable tie 100.

[0052] Figure 2 is a front view of the cable tie 100 as seen from the side of the inlet 107 of the passage 106. The cross-section of the passage 106 has the shape of a discorectangle, that is, a rectangle with semicircles at a pair of opposite sides. The blade 109 extends into the passage 106 from the first wall portion 105a being arranged at a long end of the discorectangle, such that the second end 109b of the blade 109 defines the smallest distance h to the second wall portion 105b, being arranged at the opposite long end of the discorectangle. In other embodiments, the cross-section may have other shapes such an oval shape, a rectangular shape with rounded corners, or a circular shape.

[0053] The circumference of the cord 101, before being inserted into the passage 105, is schematically illustrated by a dashed circle. In fig. 2 it can be seen that the diameter d of the cord is larger than the smallest distance h. For example, a ratio r of the diameter d to the smallest distance h may be 1.62-2.05 . This ratio r has been found to be small enough to allow the cord 101 to be pushed / pulled through the gap defined by the smallest distance h without too much effort, while still providing enough locking force once the cord 101 has been pulled through.

[0054] One reason that the cord 101 can be pushed and pulled through the passage even when the diameter d cord is larger than the distance h, is that the cord 101 comprising cellulosic fibers has a certain flexibility in a radial direction, allowing it to deform under the force exerted onto it by the blade 109, as the cord 101 is pulled through the passage 106.

[0055] Furthermore, the blade 109 is preferably mounted and configured to have resilient properties, allowing it to temporarily flex and / or move in the direction of the outlet 108 as the cord is pulled through the passage 106. The resilient properties may also contribute to withstanding forces by the cord in the direction towards the inlet 107, due to the angle a.

[0056] The blade 109 has a width w extending in a direction perpendicular to both the axis 110 and to the smallest distance h. The width w is typically 60%-80% (preferably 67%-73%, more preferably 73%-77%) of the diameter d of the cord 101. Further, the thickness of the metal blade 109 is typically 7-20% (preferably 10-15%) of the diameter d of the cord 101.

[0057] By the design consideration described above, suitable resilient properties that facilitate the locking action of the blade 109 are obtained.

Examples

Embodiment Construction

[0038]With reference to figure 1, an embodiment of a cable tie 100 of the present disclosure is described.

[0039]The cable tie 100 comprises a cord 101 having a first 102 and a second 103 end. The cord 101 comprises cellulosic fibers, e.g. in the form of a paper. Preferably, the cord is formed by twisting a paper strip along its length. The paper and the forming technique are preferably selected such that high tensile strength and a certain stretchability is obtained (e.g. a stretch at break value of 2%-5%). The diameter d of the cord 101 may be from 1.75 to 2.10 cm. A cord of such a diameter formed by a twisted paper strip may have a tensile strength (ISO 2062:1993) above 15 kg. It should be understood that the cord 101 may also have a smaller or larger diameter d. For example the diameter of the cord 101 maybe from 1.0 mm and up to 8.0 mm, depending on the intended use of the cable tie 100.

[0040]The cable ties 100 further comprises a locking head 104 fixedly attached to the first e...

Claims

1. A cable tie (100) comprising: - a cord (101) having a first end (102), a second end (103), and a diameter (d), the cord comprising cellulosic fibers, and - a locking head (104) fixedly attached to the first end (102), said locking head (104) being adapted to receive the second end (103) and retain the cable tie (100) in a closed loop configuration, wherein the locking head (104) defines a wall (105) that encircles a passage (106) having an inlet (107), an outlet (108) and a central axis (110) extending between the inlet (107) and the outlet (108), and comprises a blade (109) that extends into the passage (106) for engaging the cord (101) and which is arranged to allow displacement of the cord (101) in a first direction towards the outlet (108) while preventing displacement of the cord (101) in a second direction towards the inlet (107), wherein the blade (109) comprises a first end (109a) fixed to a first wall portion (105a) of the wall (105), and a second end (109b) defining a smallest distance (h) between the blade (109) and a second wall portion (105b) of the wall (105), the second wall portion (105b) being disposed at a side of the passage (105) opposite to that of the first wall portion (105a), with respect to the central axis (110), and wherein a ratio (r) of the diameter (d) of the cord to the smallest distance (h) is 1.62-2.05 .

2. The cable tie (100) according to claim 1, wherein the ratio (r) of the diameter (d) to the smallest distance (h) is 1.67-2.00, such as 1.71-1.95, such as 1.77-1.91.

3. The cable tie (100) according to any of the preceding claims, wherein an angle (a) between the direction of the extension of the blade (109) and the central axis (110) is 47°-62°, such as 50°-59°, such as 52°-57.

4. The cable tie (100) according to any of the preceding claims, wherein the diameter (d) of the cord (101) is 1.0-8.0 mm, such as 1.5-5.0 mm, such as 1.75-2.10 mm, such as 1.80-2.00 mm.

5. The cable tie (100) according to any of the preceding claims, wherein the smallest distance (h) is 0.60-1.20 mm, such as 0.90-1.15 mm, such as 0.95-1.15 mm, such as 1.00-1.10 mm.

6. The cable tie (100) according to any of the preceding claims, wherein the diameter (d) is defined as the mean value of at least 10 diameter values measured at different points distributed along the length of the cord (101).

7. The cable tie (100) according to any one of the preceding claims, wherein the cord (101) is formed from hemp or paper.

8. The cable tie (100) according to claim 7, wherein the cord (101) comprises a paper strip (10) twisted along its length.

9. The cable tie (100) according to any of the preceding claims, wherein the blade (109) is a metal blade.

10. The cable tie (100) according to any one of the preceding claims, wherein the stretch at break of the cord (101) is 2.0%-6.0%, such as 2.5%-4%, when measured according to ISO 2062:1993.

11. The cable tie (100) according to any of the preceding claims, wherein the cord (101) is flattened at the second end (103).

12. The cable tie (100) of any one of the preceding claims, wherein the locking head (104) comprises a body of a biodegradable material, such as a bio composite of a biodegradable and / or renewable polymer and an organic fiber material.

13. The cable (100) tie of any one of the preceding claims, wherein the inlet (107) of the passage (106) is funnel-shaped, such as trumpet-shaped.

Citation Information

Patent Citations

  • Low-treading force electric cable bundling strap with locking device

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    US20120210541A1

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    WO2022216202A1