WO2005107369A2

WO2005107369A2 - Supporting tube for flat tubeless tires

Info

Publication number: WO2005107369A2
Application number: PCT/IL2005/000487
Authority: WO
Inventors: Eldad Rubin
Original assignee: Eldad Rubin
Priority date: 2004-05-10
Filing date: 2005-05-09
Publication date: 2005-11-17
Also published as: WO2005107369A3; IL161907A0

Abstract

Wheel (100) for vehicles, which comprises a rim (104) with shaped flanges for gripping a tubeless tire (101). The rim includes a first unidirectional air valve (106) that is inserted through a first orifice, for inflating the tubeless tire; a second orifice through which a second unidirectional air valve (107) can be inserted; a tubeless tire (101), gripped by the rim (104); a backup tube (103) that is connected to the second unidirectional air valve (107) and when deflated, is attached to the rim surface that extends between the flanges. The backup tube (103), when inflated through the second unidirectional air valve, is capable of supporting a tire punctured by a piercing object. The wall of the tube consists of a rigid layer on its perimeter, that faces the inner side of the tread of the tire and is made of a rigid material for protecting the tube from being punctured by the object, when inflated; and a spacing layer that is externally affixed to the perimeter of the rigid layer. The spacing layer is made of less rigid material and is utilized for providing spacing between the inner side and the rigid layer. The less rigid material increases the contact area between the inner side and the spacing layer, in the vicinity the object.

Description

SUPPORTING TUBE FOR FLAT TUBELESS TIRES

Field of the Invention

The present invention relates to the field of wheels for vehicles. More particularly, the invention relates to a conventional wheel that comprises, in addition to its conventional tubeless tire, a backup tube, capable of supporting the conventional tire after it becomes deflated, due to, e.g., a puncture.

Background of the Invention

The wheels of most motor vehicles comprise a tire made of elastic polymeric material, which has, in generally, the shape of a circular open channel, the outside of which is a generally cylindrical tread that is in contact with the roadway, while the inside is a cylindrical opening. Said opening is matched by a mating cylindrical rim and forms with the tire a closed annular chamber that is air-tight and permits to inflate the chamber by pressurized air, which is maintained within the chamber by the seal constituted by the contact of mating cylindrical rim and the edges of said cylindrical opening.

When a tire becomes punctured, the driver has to replace the punctured wheel with another wheel, so as to drive the vehicle directly to a place where the punctured tire can be fixed.

Currently, there are several solutions aimed at sustaining at least some of the functionality of a punctured tire. For example, the driver may inject anti-flattening agent, mostly in the form of foam, into the punctured tire, after which the foam infiltrates through the puncture until it hardens and stops the air leak. Another kind of anti-flattening means consists of rubber-based elements that are installed inside the tire and prevent the tire from totally collapsing. Two examples for such anti-flattening means are described in WO 00/24598 and in EP 0606 511 Al.

WO 00/24598 discloses a vehicle wheel that comprises a tire and an anti- flattening means (50), which functions to sustain the circumferential band of the tire in a flattened condition of the tire. However, due to the relatively large spacing between the tire and the radial projections of the anti-flattening means (171 to 174), the portion of the tire that is in contact with the roadway will be so deformed, when in deflated state, that keeping driving the vehicle under such circumstances will inevitably irreversibly damage the integrity of the tire.

Other prior art technologies involve using foams for avoiding pressurized air from escaping the wheel. Usually, when a tire becomes punctured, a person (usually the driver) connects a container, in which air and foam are kept under high pressure, to the air inlet of the wheel. Upon releasing the pressurized air and foam from the container, foam is pushed by the pressurized air through the puncture in the tire until the foam hardens, after which the remaining pressurized air will inflate the tire. However, such solutions have several drawbacks. One drawback is that the lifespan of the foam injected into the tire is relatively short. Another drawback is that, while the tire is being fixed, there is a need to remove from the tire the remains of the foam, which is inconvenient and time consuming operation.

Co-pending Israeli application No. IL 157204 discloses a wheel that is resilient to punctures. The wheel of IL 157204 comprises a multi-chamber tire, the chambers of which are obtained by utilization of separating walls. That is, each two chambers are separated from one another by a corresponding wall. Every chamber is inflated independently of the other chambers, and when a chamber is punctured, the wheel can still function using the other inflated chamber(s). However, the greater the number of the punctured chambers in a wheel, the less weight can be supported by the wheel. In some cases, one or more separating walls may be damaged as well.

It is therefore an object of the present invention to provide a wheel, which will preserve most of the functionality of the tire in a case of a puncture.

Other objects and advantages of the invention will become apparent as the description proceeds.

Summary of the invention

By 'rigid' is meant hereinafter, with respect to the wall of the tube, rigid enough for making it essentially puncture-proof.

By 'less rigid' is meant that sharp objects may pierce through the wall of the tube to some extent, but objects that are less sharp will only cause the area of the tube, opposite to the punctured area of the tire, to bend inwardly.

The present invention is directed to a wheel for vehicles that comprises: a) a rim, having shaped flanges, for gripping a tubeless tire. The rim includes: a.l) a first unidirectional air valve inserted through a first orifice, for inflating the tubeless tire; a.2) a second orifice through which a second unidirectional air valve cab be inserted; b) a tubeless tire gripped by the rim; c) a backup tube that is connected to the second unidirectional air valve and when deflated, is attached to the rim surface that extends between the flanges. When the backup tube is inflated through the second unidirectional air valve, it can support a tire that is punctured by a piercing object. The wall of the tube consists of: c.l) a rigid layer on its perimeter that faces the inner side of the tread of the tire and is made of a rigid material for protecting the tube, when inflated, from being punctured by the object; and c.2) a spacing layer, externally affixed to the perimeter of the rigid layer. The spacing layer is made of less rigid material and is utilized for providing spacing between the inner side and the rigid layer. The less rigid material increases the contact area between the inner side and the spacing layer, in the vicinity the object.

Preferably, the spacing layer uniformly and externally encircles the perimeter of the rigid layer. The rigidity of the wall of the tube may gradually decrease from its inner side to its outer side, in a direction perpendicular to the wall. The spacing layer may comprise protrusions that are made of a material which is less rigid and being capable of essentially absorbing the object. They are radially and externally affixed to the perimeter of the rigid layer, and equidistantly spaced along the perimeter.

The present invention is also directed to a car wheel rim, which comprises: a) a first orifice for receiving a first unidirectional air valve that inserted through it, for inflating a tubeless tire gripped by the rim; b) a second orifice through which a second unidirectional air valve cab be inserted. The second unidirectional air valve is connected to a backup tube that when deflated, is attached to the rim surface, and when inflated, is capable of supporting a tire punctured by a piercing object. The wall of the tube consists of: b.l) a rigid layer on its perimeter that faces the inner side of the tread of the tire and is made of a rigid material for protecting the tube, when inflated, from being punctured by the object; and b.2) a spacing layer, externally affixed to the perimeter of the rigid layer and made of less rigid material. It is utilized for providing spacing between the inner side and the rigid layer and increases the contact area between the inner side and the spacing layer, in the vicinity the object.

The present invention is further directed to a backup tube that when inflated, is capable of supporting a tire of a car wheel, punctured by a piercing object. The wall of the backup tube consists of: a) a rigid layer on its perimeter that faces the inner side of the tread of the tire and is made of a rigid material for protecting the tube, when inflated, from being punctured by the object; and b) a spacing layer, externally affixed to the perimeter of the rigid layer and made of less rigid material. It is utilized for providing spacing between the inner side and the rigid layer and increases the contact area between the inner side and the spacing layer, in the vicinity the object.

Brief Description of the Drawings

The above and other characteristics and advantages of the invention will be better understood through the following illustrative and non-limitative detailed description of preferred embodiments thereof, with reference to the appended drawings, wherein: Fig. lA schematically illustrates a partial cross-sectional view of a wheel, where the backup tube is shown in deflated (i.e., in standby) state, according to the preferred embodiment of the present invention; Fig. IB schematically illustrates a partial cross-sectional view cut about plane "A- A" of Fig. lA;

- Fig. 2A schematically illustrates a partial cross-sectional view of a wheel, where the backup tube is shown in inflated (i.e., in operation) state, according to the preferred embodiment of the present invention; Fig. 2B schematically illustrates, in partial view, a cross-sectional view cut about plane "B-B" of Fig. 2A;

- Fig. 3 schematically illustrates a partial cross-sectional view of an ideal situation where the backup tube shown in Figs. 1 and 2 is inflated;

- Fig. 4 schematically illustrates in partial cross-sectional view a problem that may arise when inflating the backup tube shown in Figs. 1 and 2;

- Figs. 5A and 5B schematically illustrate, in partial cross-sectional view, a solution to the problem illustrated in Fig. 4, according to one preferred embodiment of the present invention; and Fig. 6 schematically illustrates, in cross-sectional view, a solution to the problem illustrated in Fig. 4, according to another preferred embodiment of the present invention.

Detailed Description of Preferred Embodiments

With respect to the figures, like reference numerals mean like elements and components.

Figs. lA and IB schematically illustrate partial cross-sectional views of a wheel, where the backup tube is shown in standby state, according to the present invention. Wheel 100 comprises a conventional tire 101 and additional, backup, tube 103, which is air-tight and equipped with a unidirectional air inlet for inflating it. Backup tube 103 is supported by the wheel rim 104 and is contained within a circular channel that is formed by the tire 101 and the rim 104. Backup tube 103 is a closed, air-tight, annular channel, the outside wall of which is generally cylindrically-shaped that is intended to be in contact with, and to support, the inner side of the tread 108 of tire 101 when backup tube 103 is inflated.

Wheel 100 has essentially cylindrically shaped rim 104, which supports both the tire 101 and the backup tube 103 and provides, together with tire 101, an air-tight compartment 109.

Rim 104 includes a main unidirectional air inlet 106 for inflating the tire 101, and an additional opening through which backup tube 103 can be inflated, by use of its unidirectional air inlet 107, for supporting tire 101 when it is punctured. Unidirectional air inlets 106 and 107 are preferably located at different places in rim 104. With respect to the opening in rim 104 and to rim 104 itself, rim 104 can be manufactured using any known manufacturing process, except that in order to allow inflation of tube 103, an opening is to be drilled in rim 104.

The tire 101 is shown in Figs. lA and IB in its inflated state whereas backup tube 103 is shown in its deflated state.

Figs. 2A and 2B schematically illustrate cross-sectional views of the wheel, where the backup tube is inflated, according to the present invention.

After being aware of a punctured wheel, the driver (not shown) inflates backup tube 103, via its air inlet 107, and continues driving his vehicle. Backup tube 103 is shown in Figs. 2A and 2B in inflated state and supporting tread 108 of tire 101 from the inside of tire 101.

Fig. 3 schematically illustrates, in partial cross-sectional view, a situation where the backup tube shown in Figs. 1 and 2 is inflated. Tire 301 is shown punctured by sharp object 302, and tube 304 (only part of it is shown) is shown inflated to support tire 301. In the situation shown in Fig. 3, the external surface wall 303 of tube 304 (see also 405 in Fig. 4) and the inner surface of tire 301 almost fully touch each other, except for the area where the sharp object has pierced into tire 301. In the 'piercing area', wall 303 essentially matches the shape of the sharp object 304 such that there are almost no cavities between wall 303, tire 301 and object 302.

In this situation, a relatively small force will be exerted by the air pressure inside tube 304 on the inner side area 305, and the sharp object 302 will not puncture tube 303. Such a situation can be obtained only if the material, from which tube 303 is made of, is sufficiently soft, thin and elastic. In order to avoid puncture in tube 304, the material of tube 304, in particular wall 303, must be sufficiently rigid to considerably minimize the risk of being punctured.

Fig. 4 schematically illustrates, in partial cross -sectional view, a problem that may arise when inflating the backup tube shown in Figs. 1 and 2. Wall 403 of tube 405 is made of a material that is more rigid than the material of wall 303 (Fig. 3). However, being rigid, and unlike wall 303, wall 403 cannot 'wrap' sharp object 402. As a result, when the tube is fully inflated, relatively large cavities (404) will be formed between wall 403 and tire 401 and, consequently, portion 407 of wall 403 will not be supported by the corresponding portion of tire 401. Therefore, a relatively large pressure (represented by the arrows) will be exerted on portion 407 of wall 403, which will be counteracted by the tip of object 402 in a relatively small area 406. For example, assuming that the air pressure in tube 405 is 2 bars, and that the average contact area 406 between the object's tip of object 402 and the wall 403 is 1 square millimeter, the tip of object 402 will exert a force of 200 kg., which will probably puncture backup tube 405.

Therefore, a combination must be made, between the soft tube of Fig. 3 and the rigid tube of Fig. 4. Two preferred solutions are illustrated in Figs. 5 and 6.

Figs. 5A and 5B schematically illustrate, in partial cross-sectional view, a solution to the problem illustrated in Fig. 4, according to a preferred embodiment of the present invention. According to this embodiment, the wall 503 of the tube comprises two layers, a rigid layer 504 and a spacing layer 505. The rigid layer (504) is made of rigid material, whereas the spacing layer (505) is made of less rigid material. Two situations may occur with respect to the spacing layer 505: (1) sharp objects may pierce through it to some extent, as illustrated in Fig. 5A, and (2) objects that are less sharp will only cause the area of the tube opposite to the punctured area of the tire to bend inwardly, towards the center (not shown) of the rim, as illustrated in Fig. 5B. The spacing layer 505 is a spacing layer between rigid layer 504 and the inner side 509 of tire 501 and is capable of adapting itself to the shape of the piercing object and to 'absorb' most of the piercing object 502.

In one embodiment, wall 503 of the tube comprises two distinct layers, as shown in Figs. 5A and 5B; i.e., a rigid layer 504 and a spacing layer 505, which his less rigid. In another embodiment, the wall of the tube comprises one layer, with gradually decreasing rigidity from a maximum value, similar to the degree of rigidity of the rigid layer shown in Fig. 5, to a minimum value, from the inner side of the wall to the outer side thereof, in a direction that is perpendicular to the wall.

In another embodiment, the wall of the tube comprises two distinct layers; i.e., a rigid layer and a spacing layer, which has a lower degree of rigidity, where the spacing layer is formed by teeth like element, substantially as described in connection with Fig. 6.

Fig. 6 schematically illustrates, in partial cross-sectional view, a solution to the problem illustrated in Fig. 4, according to another preferred embodiment of the present invention. According to this embodiment, the wall 607 of tube 604 comprises a rigid layer 601 and a spacing layer 614 in the form of protrusions, such as protrusion 602, which are radially, externally and equidistantly affixed to the outer surface 605 of layer 601. Protrusions 602 are made of less rigid material. When tube 604 is fully inflated, the distal ends 610 of protrusion 602 fully extend to support the inner side 611 of tire 608.

As a result of the spaces (e.g., space 609) between the protrusions and of the fact that a puncture may occur anywhere, with respect to the tread of a tire, it may often occur that an object that punctures tire 608 will enter one of these spaces. Object 603 is shown protruding into such a space, as an example to such an occurrence. In such cases, the wall 607 of tube 604 will remain intact. In other cases, a piercing object may pierce, in addition to tire 608, through one of the protrusions. For example, piercing object 606 is shown piercing protrusion 612. Because the teeth elements 602 are made of less rigid materials, a pierced protrusion will become wider. The spaces between adjacent protrusions allow such expansion.

Spacer layer 612 provides some isolation between the rigid layer 601 of tube 604 to sharp objects, as exemplified hereinbefore with respect to exemplary objects 603 and 606. However, if a sharp object, the length of which is longer than the sum of the spacing 612 and width 613 of tire 608, pierces tire 608, rigid layer 601 will protect tube 604 from being punctured, in which case, rigid layer 601 may bend inwards in a way shown in Figs. 5A and 5B.

It is noted that, a sharp object pierces a tire because of a pressure that is exerted by the vehicle weight, via the tires of its wheels, on the sharp object. Therefore, if a sharp object fully penetrates the wall of a tire, there is no force that can push it further inward, into the tire. Therefore, penetration is ended when the sharp object's distal end coincides with the tire's outer surface.

While some embodiments of the invention have been described by way of illustration, it will be apparent that the invention can be carried into practice with many modifications, variations and adaptations, and with the use of numerous equivalents or alternative solutions that are within the scope of persons skilled in the art, without departing from the spirit of the invention or exceeding the scope of the claims.

Claims

1. Wheel for vehicles which comprises: a) a rim, having shaped flanges, for gripping a tubeless tire, said rim includes: a.l) a first unidirectional air valve inserted through a first orifice, for inflating said tubeless tire; a.2) a second orifice through which a second unidirectional air valve cab be inserted; b) a tubeless tire gripped by said rim; c) a backup tube connected to said second unidirectional air valve and when deflated, attached to the rim surface extending between said flanges, said backup tube, when inflated through said second unidirectional air valve, being capable of supporting a tire punctured by a piercing object, wherein the wall of said tube consists of: c.l) a rigid layer on its perimeter, said rigid layer facing the inner side of the tread of said tire and is made of a rigid material for protecting said tube, when inflated, from being punctured by said object; and c.2) a spacing layer, externally affixed to the perimeter of said rigid layer, said spacing layer is made of less rigid material and is utilized for providing spacing between said inner side and said rigid layer, said less rigid material increasing the contact area between said inner side and said spacing layer, in the vicinity said object.

2. Wheel according to claim 1, in which the spacing layer uniformly and externally encircles the perimeter of the rigid layer.

3. Wheel according to claim 1, in which the rigidity of the wall of the tube gradually decreases from its inner side to its outer side, in a direction perpendicular to said wall.

4. Wheel according to claim 1, in which the spacing layer comprises protrusions, which are radially and externally affixed to the perimeter of the rigid layer, and equidistantly spaced along said perimeter, said protrusions are made of a material that is less rigid and being capable of essentially absorbing the object.

5. A car wheel rim, which comprises: a) a first orifice for receiving a first unidirectional air valve inserted through it, for inflating a tubeless tire gripped by said rim; b) a second orifice through which a second unidirectional air valve cab be inserted, said second unidirectional air valve being connected to a backup tube that when deflated, is attached to the rim surface, and when inflated, being capable of supporting a tire punctured by a piercing object, wherein the wall of said tube consists of: b.l) a rigid layer on its perimeter, said rigid layer facing the inner side of the tread of said tire and is made of a rigid material for protecting said tube, when inflated, from being punctured by said object; and b.2) a spacing layer, externally affixed to the perimeter of said rigid layer, said spacing layer is made of less rigid material and is utilized for providing spacing between said inner side and said rigid layer, said less rigid material increasing the contact area between said inner side and said spacing layer, in the vicinity said object.

6. A backup tube that when inflated, being capable of supporting a tire of a car wheel, punctured by a piercing object, the wall of said backup tube consists of: a) a rigid layer on its perimeter, said rigid layer facing the inner side of the tread of said tire and is made of a rigid material for protecting said tube, when inflated, from being punctured by said object; and b) a spacing layer, externally affixed to the perimeter of said rigid layer, said spacing layer is made of less rigid material and is utilized for providing spacing between said inner side and said rigid layer, said less rigid material increasing the contact area between said inner side and said spacing layer, in the vicinity said object.