Textile and device for increasing the grip of a tyre on a slippery terrain
Patent Information
- Application Number
- EP2023794086
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-10-06
- Filing Date
- 2023-10-04
- Publication Date
- 2025-08-20
AI Technical Summary
Existing solutions for improving tire grip on slippery surfaces, such as snow tires, chains, and textile devices, are either cumbersome, damage vehicles or road surfaces, or are not suitable for heavy goods vehicles which face greater constraints.
A textile device with a seamless rectilinear knitting structure using multi-strand continuous yarns of reinforced polyester fibers and ultra-high molecular weight polyethylene fibers, combined with elastic means, provides enhanced grip and resistance for heavy goods vehicles by creating a hydrophobic, abrasion-resistant, and deformation-resistant 'sock' that can be easily mounted on tires.
The device significantly increases tire grip on snowy surfaces while withstanding high mechanical stresses and maintaining durability, allowing for safe driving on both snowy and dry roads without damage, and can be easily mounted on large tires without lifting the wheel.
Smart Images
Figure 1.1
Abstract
Description
Description Title: Textile and device for increasing the grip of a tire on slippery ground
[0001] The present disclosure relates to a textile and a device for increasing the grip of a tire on slippery ground. Technical field
[0002] This disclosure relates to the field of vehicle equipment. It relates more particularly, but not exclusively, to so-called "heavy goods" vehicles, i.e. in particular vehicles whose total laden weight may exceed 3.5 tonnes (i.e. 3500 kg). These may be vehicles for both passenger transport and goods transport. Prior art
[0003] It is well known to use special tires, called snow tires. This solution is effective but requires changing the tires (or corresponding wheels) for winter use and then again in spring. You must then store a set of tires all year round.
[0004] Another solution is to use chains. Installing them can be difficult and must be done on snow. Driving with chains on a snow-free road is not recommended because they can damage certain mechanical parts of the vehicle and impair driving comfort. In addition, chains significantly wear down the road surface when there is no snow.
[0005] There are also textile devices, also called "socks," which are used to cover the tire when it has to roll on snow. These devices are easier to install than chains. Document EP2006127 describes a fabric chain for tires.
[0006] Document FR2987313A1 proposes a device capable of being interposed between a sliding support surface and a mobile in contact with this support surface, with a view to increasing the adhesion between the mobile and the support surface, comprising: - an adhesion knitted structure of which a first face, called the front face, is intended to be in contact with the sliding support surface, and of which the second face, opposite the first and called the rear face, is intended to be in contact with the mobile, - the adhesion knitted structure being made up of at least one yarn forming a plurality of blocked stitches, - elastic holding means bordering the grip knit structure and associated to this, to maintain the device on a part of the mobile intended to come into contact with the sliding support surface.
[0007] Such a device is very well suited to form a "sock" for a relatively light automobile-type vehicle (less than 3.5 tonnes) and gives excellent results. It allows for good grip even on icy ground and, compared to other textile devices, has significantly increased wear resistance.
[0008] The present disclosure therefore aims to provide means which make it possible to obtain similar results also for “heavy” vehicles for which the constraints are greater than for a car-type vehicle. Summary
[0009] This disclosure improves the situation.
[0010] A textile intended to increase the grip of a tire on a slippery surface is proposed, having a knitted structure obtained by seamless rectilinear knitting and comprising a continuous multi-strand yarn and at least one continuous single-strand yarn.
[0011] According to the present disclosure, this textile is such that: the multi-strand continuous yarn comprises at least: - a polyester fiber reinforced with a first linear reinforcement density, - a polyester fiber reinforced with a second linear reinforcement density, and - an ultra-high molecular weight polyethylene fiber, and that the continuous single-strand yarn is a polyester monofilament.
[0012] Such a structure is hydrophobic and is therefore suitable for use in contact with snow or ice. It also has very high abrasion resistance thanks to its original composition as well as good resistance to deformation to prevent the textile from stretching, for example.
[0013] The features set out in the following paragraphs may, optionally, be implemented, independently of each other or in combination with each other:
[0014] - the first linear reinforcement density is between 400 and 1000 dtex;
[0015] - the second linear reinforcement density is between 2000 and 3000 dtex;
[0016] - ultra-high molecular weight polyethylene fiber has a linear density between 250 and 1000 dtex;
[0017] - the single-strand continuous yarn has a diameter between 0.1 and 0.5 mm. For this characteristic, the single-strand continuous yarn can have a diameter between 0.15 and 0.25 mm and a count between 300 and 600 dtex;
[0018] - the said textile is made using a double pique jersey knitting process.
[0019] According to another aspect, the present disclosure also relates to a device intended to increase the grip of a tire on a slippery surface comprising a central annular grip knitted structure, as well as elastic means, also with a knitted structure, arranged on either side of the central annular structure.
[0020] In a novel and advantageous manner, the annular central adhesion knitting structure is made with a textile as described above.
[0021] The features set out in the following paragraphs may, optionally, be implemented, independently of each other or in combination with each other:
[0022] - a continuous seamless knitted intermediate strip is placed between the annular central grip knitted structure and elastic means; in this case, the intermediate strip may be a knitted strip with a double jersey structure;
[0023] - the knitted intermediate strip is made with at least one continuous multi-strand yarn comprising at least: - a polyester fiber reinforced with a first linear reinforcement density, - a polyester fiber reinforced with a second linear reinforcement density, and - an ultra-high molecular weight polyethylene fiber;
[0024] - elastic means are made from elastane. Brief description of the drawings
[0025] Other features, details and advantages will become apparent upon reading the detailed description below, and upon analyzing the attached drawings, in which: Fig. 1
[0026] [Fig. 1] shows a schematic of stitches for a knitted fabric according to the present disclosure. Fig. 2
[0027] [Fig. 2] shows a tire equipped with a device according to the present disclosure. Fig. 3
[0028] [Fig. 3] shows a half cross-section of a tire equipped with a device according to the present disclosure. Description of the embodiments
[0029] A person skilled in the textile field, and more particularly in the field of knitting, will recognize in Figure 1 a diagram of the stitches of a knitted device. In this diagram, five knitting cycles appear. These cycles are numbered C1 to C5. For each cycle, a single pattern is represented.
[0030] For cycles C1, C2, C4 and C5, Figure 1 illustrates a knitting cycle corresponding to a 1 x 1 locknit knitting pattern, also known as double jersey. Cycle C3, in the center, corresponds to a double piqué knitting pattern. The circles on the diagram illustrate the start of the stitch pattern and show that the cycles are knitted in a staggered pattern. The cycles give relief to the textile (formation of a mini chenille) allowing the creation of a grippy texture, particularly useful for cycle C3.
[0031] This mesh schematization is intended for the production of a device commonly called a "sock" and which is used to increase the grip of a tire on a slippery road, in particular a snowy one. In such a device, the part of the device for increasing grip intended to be located between the tire and the (snowy) road is subject to significant constraints and is at the heart of the present disclosure. This part corresponds to cycle C3 of Figure 1. It is located in a central position in the device. The parts of the device for increasing grip corresponding to cycle C2, respectively to cycle C1 are arranged symmetrically to the part corresponding to cycle C3 with respect to cycle C4, respectively cycle C5.
[0032] The part of the device for increasing the adhesion corresponding to cycle C3 corresponds to an improvement of the section 9 of the structure 4 disclosed by the document FR2987313 to which reference is made here. Figures 2 and 3 of the present disclosure correspond to Figures 1 and 3 of this prior art document and the references of this prior art document are repeated here.
[0033] Thus, a device 1 as shown in Figures 2 and 3 is capable of being interposed between a sliding support surface 2 (Figure 3) and a tire 3 in contact with the sliding support surface 2, in order to increase the grip between the tire 3 and the sliding support surface 2. The device 1 comprises: - an adhesion knitted structure 4 of which a first face 5, called the front face, is intended to be in contact with the sliding support surface 2, and of which the second face 6, opposite the first face 5 and called the rear face, is intended to be in contact with the tire 3, the grip knit structure 4 being made up of at least one thread forming a plurality of blocked stitches, - elastic holding means 7 for holding the device 1 on the tire 3.
[0034] In the example shown, the sliding support surface 2 may be any covering intended to be in contact with the tire, for example a snowy or icy road. The device 1 takes the form of a textile “sock” of annular shape capable of matching the external shape of a tire, namely its tread and at least part of its lateral sidewalls.
[0035] The grip knit structure substantially adopts the shape of a section 9 of seamless tubular knit comprising a tread shape 8. This section 9 of tubular knit has a longitudinal axis 12 which corresponds to the axis of rotation of a wheel fitted with the tire 3. It should be noted that the section 9 constituting the grip knit structure 4 is not shown in Figures 2 and 3 exactly in the shape of a tube, because this section 9 is deformed by the elastic holding means 7 to at least partially cover the sidewalls of the tire 3.
[0036] In a manner not disclosed in the aforementioned document FR2987313, an intermediate strip 17 is placed each time between the section 9 of tubular knit and elastic holding means 7. As can be seen from Figures 2 and 3, the elastic means 7 are in the form of two elastic rings, an inner elastic ring 13 and an outer elastic ring 14, distinct from each other. The section 9 has an outer end 10 and an inner end 11 and an intermediate strip 17 is placed in each case between, on the one hand, the outer end 10 and the outer elastic ring 14 and, on the other hand, the inner end 11 and the inner elastic ring 13. The elastic rings exert a resulting centripetal elastic force towards the longitudinal axis 12 via an intermediate strip 17 in each case so that the grip knit structure 4 fits the outer surface of the tire as closely as possible.Thus, the elastic rings tend by elastic return to reduce the diameter of the inner end 11 and the outer end 10 of the section 9.
[0037] In this device 1, the section 9 is produced in accordance with cycle C3 of figure 1, each intermediate strip 17 is produced in accordance with cycles C2 and C4 which are similar and the elastic holding means 7, that is to say the inner elastic ring 13 and the outer elastic ring 14, are produced in accordance with cycles C1 and C5 of figure 1, these two cycles (C1 and C5) being similar.
[0038] The composition of section 9 (cycle C3 corresponding to the tread) has been adapted for use on heavy goods vehicles, i.e. vehicles with a total laden weight exceeding 3.5 tonnes and up to 39 tonnes. The stresses experienced by the "sock" are much higher than for a motor vehicle (less than 3.5 tonnes).
[0039] Section 9 is a cylindrical type knit or a soft round knit, obtained by flat knitting in shape and has no seams. As shown, this section 9 corresponds to cycle C3 of Figure 1 and is knitted in double piqué. It is made with a multi-strand continuous yarn and at least one single-strand continuous yarn.
[0040] Preferably, the structure of the section 9 is vanished, so that the continuous single-strand yarn appears on the second face 6, or rear face (tire side), and does not appear on the first face 5, or front face. The single-strand yarn is of a small diameter (between 0.1 mm and 0.5 mm, preferably between 0.15 and 0.25 mm, for example 0.2 mm) compared to that of the continuous multi-strand yarn which is the main constituent yarn of the structure of the tread, i.e. the section 9. The two continuous yarns, multi-strand and single-strand, follow the same path of blocked stitches, and are preferably knitted together according to the known technique of vanishing.
[0041] The multi-strand continuous yarn is advantageously made of high-tenacity hydrophobic polymer textile fibers, and comprises a number of strands advantageously greater than 200, preferably of the order of 500 strands. The multi-strand continuous yarn comprises three types of fibers (and is preferably made up of only these three types of fibers): - a polyester fiber reinforced with a first linear reinforcement density, - a polyester fiber reinforced with a second linear reinforcement density, and - an ultra-high molecular weight polyethylene fiber.
[0042] The polyester fiber reinforced with a first linear reinforcement density has, for example, a linear reinforcement density of between 400 and 1000 dtex (one kilometer of yarn then weighs between 40 and 100 g). According to a particular non-limiting embodiment, this fiber is made of a high-tenacity polyester, count 600 dtex (+ / -25) and is formed of approximately 100 filaments. It has a tensile strength of 3000 N (+ / -150) and a nominal elongation of 24% (+ / -3).
[0043] The polyester fiber reinforced with a second linear reinforcement density has, for example, a linear reinforcement density of between 2000 and 3000 dtex (one kilometer of yarn then weighs between 200 and 300 g). According to a particular non-limiting embodiment, this fiber is made from a high-tenacity polyester, count 2400 dtex (+ / -100) and is made up of approximately 400 filaments. It has a tensile strength of 12700 N (+ / -600) and a nominal elongation of 25% (+ / -4).
[0044] The ultra-high molecular weight polyethylene fiber has a count of, for example, between 300 and 600 dtex. In a particular (and non-limiting) embodiment, this multi-filament fiber has a count of 440 dtex. It has a tensile strength of between 1000 and 1800 N with a nominal elongation at break of 3 to 4%. This is, for example, a UHMWPE type polyethylene fiber marketed under the Dyneema brand, with a reference SK60 or SK62 or SK63 or SK75.
[0045] Continuous monofilament yarn is a polyester monofilament. It is preferably a monofilament made of polyester polymer with a density of 1.38 g / cm 3and a melting temperature of 255°C. This monofilament preferably has good UV resistance, good dimensional stability and good abrasion resistance.
[0046] It is possible to provide two single-strand yarns knitted with the main multi-strand yarn of the knitting. According to another variant, it is possible to provide a single-strand yarn only in every other row, for example.
[0047] The single-strand yarn limits the deformation of the knit, limits its elasticity, and fixes the relief defined by the stitches, while the continuous multi-strand yarn creates this relief and improves adhesion.
[0048] The materials used here are hydrophobic materials with high toughness.
[0049] In section 9, the polyester fiber reinforced with a second linear density is for example the majority by weight, for example from 50 to 65% by weight. The proportion of ultra-high molecular weight polyethylene fiber by weight is advantageously between 15 and 20%, while the single-strand yarn represents between 5 and 10% of the mass of the textile forming section 9, the remainder being made up of the polyester fiber reinforced with the first linear density (from 5 to 30%).
[0050] Concerning the knitting of section 9, reference is made here to figures 4 to 7 of document FR2987313A1 (from the same inventor as the present disclosure) and to the corresponding passage page 10 line 5 to page 11, line 3.
[0051] As mentioned above, in an original manner, on each side of the section 9 there is an intermediate strip 17, the two intermediate strips being arranged symmetrically with respect to the section 9. These two strips are flexible and are adapted to a large device to facilitate mounting on the tire 3. For a heavy goods vehicle, the size of the rims easily exceeds 20” (i.e. 50 cm) and the width of the tire is typically between 300 and 400 mm. These intermediate strips 17 correspond to cycles C2 and C4 of figure 1. These strips Intermediate 17s are also particularly suited to the dimensions of heavy goods vehicle tires and high mechanical constraints.
[0052] It is proposed to adapt the composition of these intermediate bands to that of section 9 but as a variant, it is possible to use other fibers to produce the intermediate bands 17.
[0053] According to a preferred embodiment, the composition of the intermediate strips corresponds to that of the tread (section 9) but without single-strand yarn (monofilament). The relative proportions between the two remaining polyester fibers and the ultra-high molecular weight polyethylene can remain unchanged. The presence of ultra-high molecular weight polyethylene is advantageous because it promotes the plating and centering of the sock on the tire. It also prevents abrasion and tearing of the sock.
[0054] According to another variant, the intermediate strips 17 may comprise only the two polyester fibers, that is to say a polyester fiber reinforced with a first reinforcement density and another polyester fiber reinforced with a second reinforcement density. It is possible here to have, for example, as in the embodiment described above for the section 9, the polyester fiber measuring 600 dtex and the polyester fiber measuring 2400 dtex. The proportions may here also correspond to the relative proportions of these two fibers in the tread (section 9).
[0055] Other compositions may be envisaged. For better positioning of the device on the tire 3 while the corresponding vehicle is moving, it is provided that the intermediate strips 17 are lighter (for example mass per unit area) than the tread (section 9) so as to promote the centering of the tread on the tire 3.
[0056] The elastic holding means 7 are arranged symmetrically with respect to the structure comprising the section 9 and the intermediate strips 17. These elastic holding means 7 correspond to the cycles C1 and C5 of figure 1. These elastic means may be of the same type as the elastic holding means 7 described in the aforementioned document (FR2987313A1) page 11, line 4 to page 12, line 15.
[0057] In an alternative embodiment, the elastic holding means 7 (inner elastic ring 13 and outer elastic ring 14) can be made by knitting, preferably double jersey, only with elastane.
[0058] The entire device 1 is preferably knitted seamlessly, as described above. This allows for a seamless device. The parts corresponding to the five cycles C1 to C5 are knitted in a chained manner. Industrial application
[0059] These technical solutions can be applied in particular to "anti-slip" devices for vehicle tires, and more particularly for heavy goods vehicles with a total laden weight of several tons or tens of tons. With the use of hydrophobic fibers, the device obtained is perfectly suited to use on a snow-covered road surface.
[0060] The proposed tread textile has been tested and allows for driving over 30 kilometers without snow, on dry roads, without tearing. This demonstrates the high abrasion resistance of the proposed textile.
[0061] The proposed structure, with a total of five structures assembled together, allows manual mounting even on large tires (e.g. tires on 22.5-inch rims and 385 mm wide). Mounting can be carried out on a tire without having to lift the corresponding wheel. The proposed structure automatically centers itself on the tire as soon as the vehicle travels a few hundred meters.
[0062] This disclosure is not limited to the examples of embodiment described above, only by way of example, and to the variants mentioned, but it encompasses all the variants that a person skilled in the art may envisage within the framework of the protection sought.
Claims
Claims
1. Textile (C3) for increasing the grip of a tire on a slippery surface having a knitted structure obtained by seamless rectilinear knitting and comprising a continuous multi-strand yarn and at least one continuous single-strand yarn, characterized in that the continuous multi-strand yarn comprises at least: - a polyester fiber reinforced with a first linear reinforcement density, - a polyester fiber reinforced with a second linear reinforcement density, and - an ultra-high molecular weight polyethylene fiber, in that the single-strand continuous yarn is a polyester monofilament, and in that the multi-strand continuous yarn and the at least one single-strand continuous yarn are knitted together by vanishing.
2. Textile according to claim 1, characterized in that the first linear reinforcement density is between 400 and 1000 dtex.
3. Textile according to one of claims 1 or 2, characterized in that the second linear reinforcement density is between 2000 and 3000 dtex.
4. Textile according to one of claims 1 to 3, characterized in that the ultra-high molecular weight polyethylene fiber has a linear density of between 250 and 1000 dtex.
5. Textile according to one of claims 1 to 4, characterized in that the single-strand continuous yarn has a diameter of between 0.1 and 0.5 mm.
6. Textile according to claim 5, characterized in that the single-strand continuous yarn has a diameter of between 0.15 and 0.25 mm and a count of between 300 and 600 dtex.
7. Device for increasing the grip of a tire on a slippery surface comprising an annular central grip knitted structure (9), as well as elastic means (7), also with a knitted structure, arranged on either side of the annular central structure (9), characterized in that the annular central grip knitted structure (9) is made with a textile according to one of claims 1 to 6.
8. Device according to claim 7, characterized in that a continuous seamless knitted intermediate strip (17) is placed each time between the annular central adhesion knitted structure (9) and elastic means (7).
9. Device according to claim 8, characterized in that the intermediate strip (17) is a knitted strip with a double jersey structure.
10. Device according to one of claims 8 or 9, characterized in that the knitted intermediate strip is made with at least one continuous multi-strand yarn comprising at least: - a polyester fiber reinforced with a first linear reinforcement density, - a polyester fiber reinforced with a second linear reinforcement density, and - an ultra-high molecular weight polyethylene fiber.
11. Device according to one of claims 8 to 10, characterized in that the elastic means are made from elastane.