Technical Field

The present invention relates to a safety device for wheels, particularly for cars or other vehicles.

Background Art

Tire punctures have always been one of the greatest problems linked to this type of product.

In the presence of punctures or similar occurrences, such as cuts or gashes following impacts with blunt instruments, the pressurized air inside the tire comes out and the internal pressure decreases which allows the wheel to support the vehicle.

It is easy to imagine how such an occurrence involves the inability of the vehicle to move, interrupting the journey if the vehicle is already in motion, or preventing it from starting again if the vehicle is not yet in motion.

The user of the vehicle, to be able to continue his/her journey, is forced to call for help or perform laborious punctured tire change operations.

The need is therefore known to cope with punctures or similar occurrences, making it safe and easy for the user of the wheel to operate.

In this regard, a first type of safety devices for wheels provides for the use of rigid elements interposed between the tread and the rim of the wheel.

The rigid elements are resting on the rim of the wheel and surround it at least in part.

In normal tire use conditions, the elements are spaced from the tread by an interspace containing the compressed air which gives pressure to the wheel. In case of a puncture, the air escapes and the interspace thins down until the tread makes contact with the rigid elements.

This way, the wheel does not completely lose its functionality and can continue to run in contact with road surfaces thereby enabling the user, e.g., to reach spare-part garages or other places able to repair the damage.

A drawback of this first type of device is related to the rigidity of the elements which does not ensure a good wheel functionality when the latter is deflated. Furthermore, the rigid elements must be installed on the wheel rim, resulting in complex and expensive assembly operations.

A second type of safety device for wheels is also known which involves the use of a double inner tube, a first outer tube, interposed between the wheel rim and the tread, and a second inner tube, fitted in the first tube.

Under normal use conditions, both tubes contain pressurized air.

In case of the tread becoming punctured, the first tube deflates and adheres to the inner tube so as to ensure wheel functionality.

This second type of devices has some drawbacks.

A first drawback concerns the fact that the inner tube is not exempt from punctures and the risk of a complete wheel puncture therefore continues to exist. Another drawback concerns the fact that the double tube implies a double inflation system, with two respective valves fitted in the wheel through two corresponding holes obtained on the rim.

This characteristic implies the realization of rims which are specially designed and developed industrially, making it in fact impossible to use this second type of safety devices on already existing wheels.

Description of the Invention

The main aim of the present invention is to provide a safety device for wheels which can be used both for tires mounted on newly-produced rims and for tires fitted on already existing rims.

One object of the present invention is to provide a safety device for wheels which allows to cope with punctures in a safe manner, thus allowing to maintain the control of the vehicle.

Another object of the present invention is to provide a safety device for wheels easy to fit and to use.

Another object of the present invention is to provide a safety device for wheels which allows to overcome the mentioned drawbacks of the prior art within the ambit of a simple, rational, easy and effective to use as well as affordable solution.

The above mentioned objects are achieved by the present safety device for wheels having the characteristics of claim 1.

Brief Description of the Drawings Other characteristics and advantages of the present invention will appear better evident from the description of three preferred, but not exclusive, embodiments of a safety device for wheels, illustrated by way of an indicative, but non- limiting, example in the accompanying drawings, wherein:

Figure 1 is an axonometric view of a detail in partial cross-section of the device according to the invention;

Figures 2 and 3 are a sectional view of a first embodiment of the device according to the invention;

Figure 4 is a sectional view of a second embodiment of the device according to the invention;

Figure 5 is a sectional view of a third embodiment of the device according to the invention;

Figure 6 is a sectional view of a fourth embodiment of the device according to the invention;

Figure 7 is a sectional view of a fifth embodiment of the device according to the invention;

Figures 8, 9 and 10 are sectional views of a detail of the device according to the invention;

Figure 11 is an exploded view of a detail of the device according to the invention.

Embodiments of the Invention

With particular reference to such illustrations, a safety device for wheels is globally indicated with reference number 1.

In the embodiments illustrated in the figures, the device 1 is used on a wheel 2 for cars, but its use for wheels suitable to other types of vehicles cannot be ruled out.

The wheel 2 has a tire 3, with a tread element 3a, and a rim 4 associated with each other to define a first tube 5 containing a first pressurized fluid for the support of loads acting on the tire itself.

The first inflated tube 5, therefore, allows maintaining the deformation of the wheel 2 undergoing the vehicle weight load within acceptable limits without compromising its surface grip and its running on the road surface. Preferably, the first pressurized fluid is compressed air, but the use of other types of fluid, both gaseous, e.g., nitrogen, and liquid cannot be ruled out.

The device 1 comprises at least a support body 6 fitted in the wheel 2, in particular inside the first tube 5.

The support body 6 also has a support portion 7 adapted to come at least partially in contact with the tire 3, in particular with the tread element 3 a, when the first fluid comes out of the first tube 5.

In the case of the first fluid coming out of the first tube 5, e.g., in case of a puncture or other type of rupture of the tire 3, the first tube 5 loses pressure and the tread element 3 a, under the effect of the weight of the vehicle, is brought in contact with the support portion 7.

According to the invention, the support body 6 defines a second tube 8 fitted in the first tube 5 and containing a second pressurized fluid.

In these embodiments, the second tube 8 completely surrounds the rim 4 of the first tube 5.

This way, in the event of pressure losses in the first tube 5, the tread element 3a is brought in contact with the support body 6 and the wheel 2 may continue to adhere to and slide on the surfaces thanks to the pressure given by the second fluid in the second tube 8.

Even in this case, the second fluid is of the compressed air type, but the use of other types of fluid, both gaseous, e.g., nitrogen, and liquid cannot be ruled out. Preferably, the support body 6 is made of vulcanized rubbery polymeric material, but the use of other polymeric materials or other materials compatible with the functionalities of the tire cannot be ruled out.

Usefully, the support body 6 comprises at least a protective element 9 arranged at least at the support portion 7.

The protective element 9 is adapted to coat at least in part the second tube 8 for the protection of the latter from rupture actions such as punctures, cuts, and other similar actions.

In particular, the protective element 9 has a lamellar conformation, so as to provide the element itself with flexibility. As shown in the illustrations, the support body 6 comprises a plurality of protective elements 9, fitted in the layer of polymeric material corresponding to the support portion, but the solution providing a single protective element 9 cannot be ruled out.

The protective elements 9 are arranged so as to form a continuous coating surrounding at least in part the second tube 8.

Such solution allows avoiding unprotected areas, subject to possible punctures or other type of ruptures which would allow the second fluid to come out of the second tube thereby depressurizing it.

Furthermore, the lamellar conformation of the protective elements 9 enables the protective elements 9 to maintain an elastic flexibility such as to allow the arrangement of the support body 6 around the rim 4 and, in general, inside the wheel 2 with simple folding and insertion operations.

Different solutions cannot be ruled out wherein the protective element 9 is made with different shapes, e.g. metal nets with appropriately warped meshes, or other solutions which give strength and flexibility to the protective element itself.

Advantageously, the support body 6 also comprises contact elements 10 arranged on the support portion 7 and adapted to come in contact with the tire 3 when the first fluid comes out of the first tube 5.

The contact elements 10 are protruding with respect to the support portion 7 and, coming in contact with the tread element 3a, generate vibrations perceivable by the user of the vehicle.

This solution allows to alert the user about the puncture of the tire 3 and is particularly advantageous in the case of cars or other vehicles not equipped with special sensors detecting the pressure in tires.

In the embodiments shown, the contact elements 10 are spacers facing towards the tread element 3a and arranged in three rows at the support portion 7.

Different solutions cannot however be ruled out wherein, e.g., the contact elements 10 are in different number or have different shape (irregular, triangular profiles and other shapes), or are arranged in a different way (asymmetric, in alternate rows or the like). Usefully, the support body 6 comprises at least a coating layer 11 with sound- absorbing material and arranged at least in part at the support portion 7.

This characteristic permits muffling, if not eliminating, the noise generated by the contact between the parts of the device 1 and the parts of the wheel 2 when this is in motion.

The coating layer 11 also allows the punctured wheel 2, and therefore with the tire 3 supported by the support body 6, to continue to rotate on the surfaces without emitting excessive noise.

The same characteristic, in fact, permits muffling the noises coming from any scraping of the parts in contact.

According to the invention, furthermore, the device 1 comprises inflating means 12, 19 variable between a first configuration (Figure 8), wherein the inflating means are associated with the first tube 5 for the introduction/extraction of the first pressurized fluid, and a second configuration (Figure 9), wherein they are associated with the second tube 8 for the introduction/extraction of the second pressurized fluid.

In particular, the inflating means 12, 19 comprise a valve 12, adapted to adjust the first fluid or the second fluid arising from compressor means, not illustrated for sake of simplicity.

The valve 12 comprises a valve body 13 and is partially fitted inside the first tube 5 through a hole 14 obtained in the rim 4.

More particularly, the valve 12 has a main channel 15 adapted to convey the first fluid and/or the second fluid coming from the compressor means.

In the present embodiments, the main channel 15 is obtained in the valve body 13 and has a substantially cylindrical conformation.

The valve 12 also comprises a first outlet duct 16 associated with the first tube 5.

In the first configuration, the first outlet duct 16 communicates with the main channel 15 to convey the first fluid into the first tube.

The first outlet duct 16 is obtained directly in the valve body 13 along a direction transversal to the direction of the main channel 15, but different placements cannot be ruled out. Conveniently, the valve 12 comprises a second outlet duct 17 associated with the second tube 8.

In the second configuration, the second outlet duct 17 communicates with the main channel 15 to convey the second fluid into the second tube 8.

In the present embodiments, the valve 12 comprises an extremal portion 18 screwed onto the valve body 13 and wherein the second outlet duct 17 is obtained.

In this case too, the second outlet duct 17 extends along a direction transversal to the direction of the main channel 15, but alternative solutions cannot be ruled out, e.g., wherein the second outlet duct 17 has the same direction as the main channel 15.

Conveniently, the inflating means 12, 19 comprise a connection tube 19 associated with the second outlet duct 17 and adapted to connect the second tube 8 to the valve 12.

Different solutions wherein, e.g., the valve 12 is directly connected to the second tube 8 cannot be ruled out.

As shown in Figures from 6 to 8, the valve 12 comprises a conveying element 20 inserted in the main channel 15 and having a conveying channel 21 adapted to receive the first fluid and/or the second fluid.

The conveying channel 21 communicates with the main channel 15 to convey the aforementioned fluids.

The conveying element 20 is movable along the main channel 15 for the switch from the first configuration to the second configuration.

More particularly, in the first configuration the conveying channel 21 communicates with the first outlet duct 16 to convey the first fluid into the first tube 5.

Similarly, in the second configuration the conveying channel 21 communicates with the second outlet duct 17 to convey the second fluid into the second tube 8. In the present embodiments, the conveying element 20 is the type of a tubular body fitted to measure inside the main channel 15.

Conveniently, the tubular body 20 is enveloped by O-ring elements 22 adapted to improve the adhesion of the tubular body 20 to the main channel 15. The tubular body 20 has a first extremity 23, facing towards the extremal portion 18, and a second extremity 24 opposite to the first.

The second extremity 24 comprises a thread 25 associated with the main channel 15 to form a screw-nut screw coupling with it.

In addition, the second extremity 24 comprises an adjustment seat 26 adapted to receive means for adjusting the position of the conveying element 20.

With reference to the embodiments shown, the adjustment seat 26 is shaped so that it can be associated with an Allen wrench, the function of which is to screw up the tubular body 20 in one direction or the other to move it along the main channel 15.

Conveniently, the tubular body 20 comprises a first outlet 27 and a second outlet 28 communicating with the main channel 15.

In the first configuration, the tubular body 20 is moved along the main channel with the first outlet 27 which is placed in communication with the first outlet duct 16 thus allowing the conveyance of the first fluid.

In the second configuration, the tubular body 20 is moved along the main channel with the second outlet 28 which is placed in communication with the second outlet duct 17 thus allowing the conveyance of the second fluid.

Alternative solutions cannot however be ruled out wherein, e.g., the conveying element 20 has a single outlet alternately positionable in communication with the first outlet duct 16 or the second outlet duct 17.

Furthermore, the use is not ruled out of elements alternative to the conveying element 20 such as, e.g., movable partitions interposed between the main channel 15 and the outlet ducts 16, 17 and adapted to open/close depending on the tube that has to be inflated.

Advantageously, the valve 12 comprises first sealing means 29, 30 adapted to prevent the coming out of said first fluid and said second fluid through the main channel 15, i.e., adapted to prevent the fluids from escaping from the tubes 5, 8. In particular, the first sealing means 29, 30 comprise a closing element 29 communicating with the main channel 15 and having a coupling extremity 31 variable between a closed configuration, wherein it is hermetically sealed, and an open configuration, wherein it is open to allow the outflow of the first fluid and/or of the second fluid through the main channel 15.

The coupling extremity 31 is closable with a traditional small valve, not shown for simplicity in the illustrations, used to tighten the valve elements known in the prior art, but the use of different small valves or other similar elements cannot be ruled out.

By unscrewing the traditional small valve, the main channel 15 is put into communication with the outside and, therefore, is available to allow the pressurized fluids in the tubes 5, 8 to come out or to be introduced.

In particular, by unscrewing the small valve, the adjustment seat 26 is made accessible so as to enable the screwing or unscrewing of the conveying element 20.

The first sealing means 29, 30 also comprise a sealing element 30 adapted to secure the valve 12 to the rim 4, and associated with the closing element 29 and the valve body 13 for connecting the coupling extremity 31 to the main channel 15.

In the present embodiments, the sealing element 30 is the type of a ring nut which can be screwed to the valve body 13.

In particular, the ring nut 30 is screwed to the portion of the valve body 13 which, through the hole 14, remains external to the rim 4, and is screwed in abutment with the rim itself.

The ring nut 30 is also associated with the closing element 29 to form a screw- nut screw coupling and to allow the connection between the coupling extremity 31 and the main channel 15.

The valve 12 also comprises second sealing means 32, 34 adapted to prevent the second fluid from coming out of the second tube 8.

In particular, the second sealing means 32, 34 comprise a compartment 32 interposed between the main channel 15 and the second outlet duct 17, communicating with them and having a constricting extremity 33 in the proximity of the main channel itself.

Furthermore, the second sealing means 32, 34 comprise a closing body 34 movable between a closed position (Figure 9) and an open position (Figure 10).

In the closed position, the closing body 34 is engaged with the constricting extremity 33 so as to aeraulically disconnect the main channel 15 and the second outlet duct 17, so as to prevent the conveyance of the pressurized fluid returning from the second tube 8.

In the open position, the closing body 34 is moved away from the constricting extremity 33 so as to aeraulically connect the main channel 15 and the second outlet duct 17, so as to allow the flow of the pressurized fluid.

More particularly, the closing body 34 is facing to the conveying element 20. The conveying element 20, in the open position, is pushed against the closing body 34 and is adapted to support the latter away from the constricting extremity 33.

In the present embodiments, the closing body 34 is the type of a sphere and is associated with a spring 35 arranged on the opposite side of the constricting extremity 33 with respect to the sphere itself.

The spring 35 is adapted to push the sphere itself against the constricting extremity 33 for the closure of the latter.

Alternative solutions cannot be ruled out wherein no spring 35 is present or wherein in place of the sphere 34 there are other closing bodies 34.

In a first embodiment, shown in Figures 2 and 3, the second tube 8 is only filled with the second pressurized fluid.

In a second embodiment, shown in figure 4, the second tube 8 is partially filled with structural material 36 of the type of honeycomb material.

In a third embodiment, shown in figure 5, the second tube is partially filled with structural material 36 of the type of foam material.

Both in the second embodiment, and in the third embodiment, the structural material 36 provides the support body 6 with shape memory, useful for withstanding the deforming loads it has to undergo when the tire 3 is punctured.

At the same time, the inherent characteristics of the above-mentioned materials provide flexibility to the support body 6 useful for mounting the latter around the rim 4 and in the wheel 2.

The operation of the present invention is as follows.

The conveying element 20 is positioned inside the main channel 15 by screwing the adjustment seat 26 up to put the main channel 15 in communication with the first outlet duct 16 (first configuration, Figure 8) so as to inflate the first tube 5. Similarly, to inflate the second tube 8, the adjustment seat 26 is screwed up to bring the conveying element 20 to such a position as to place the main channel in communication with the second outlet duct 17 (second configuration, Figure 9).

By further tightening the adjustment seat 26, the conveying element 20 is brought in contact with the closing body 34 (Figure 10) so as to push it away from the constricting extremity 33 to allow the second fluid to come out of the second tube 8, deflating it.

With the tubes 5, 8 inflated, the wheel 2 can be used normally to run a vehicle gripping on sliding surfaces.

In the event of puncture or rupture of the tire 3, the coming out of the first pressurized fluid brings the tread element 3a in contact with the support portion 7 (Figure 3).

The support body 6, at this point, provides the tire 3 with the pressure required to cope with the acting loads, allowing the wheel to maintain a grip and a sliding capacity such as to enable the vehicle to be driven.

The protective elements 9 prevent the cause of the puncture, e.g., a nail or other sharp material, from also affecting the support body 6, preserving the second tube 8.

The contact elements 10, when the tread element 3a is approaching, are in contact with the latter generating vibrations perceivable by the driver, making him/her aware of the puncture which has occurred.

In a first embodiment (Figures 2 and 3), the support body 6 supports the tire 3 thanks only to the pressure of the second pressurized fluid present in the second tube 8.

In a second embodiment (Figure 4) and in a third embodiment (Figure 5), the support body 6 supports the tire 3 thanks to both the second pressurized fluid present in the second tube 8, and the bearing action of the structural material 36. In a fourth embodiment (Figure 6), the support body 6 has a positioning element 37 placed in contact with the tread element 3a and adapted to balance the position of the support body itself within the first tube 5. In a fifth embodiment (Figure 7), the support body 6 defines a second double tube, i.e. having two compartments 8a and 8b.

Such characteristic allows to balance and center the support body 6 inside the first tube 5.

Embodiments comprising one or more combinations of the aforementioned embodiments cannot be ruled out.

It has in practice been found that the described invention achieves the intended objects and in particular the fact is stressed that the safety device for wheels can be used both for tires fitted on newly-produced rims, and for tires installed on already existing rims.

The inflating means variable between a first configuration and a second configuration, in particular the use of a conveying element that permits placing the main channel in communication with the first tube and with the second tube alternately, allows using a single valve inserted in a single hole obtained on the rim of the vehicle.

This way, the rims of already existing wheels can be used without further intervention, thus making possible the installation of the device on already existing vehicles.

This characteristic also allows using newly-produced rims identical to traditional ones, so the putting into production of the device is made easier because it is no longer necessary to plan again the start of production of the car rims.

Thanks to the characteristics of the support body, furthermore, the device allows coping with punctures in a safe way, and permits maintaining the control of the vehicle.

The support action of the second tube, in fact, allows the driver to continue to drive the vehicle without losing control, at least until he/she reaches a safe place or a workshop where the damage can be repaired.

The contact elements, moreover, warn the driver of the puncture which has occurred.

Finally, the provided safety device for wheels is easy to install and easy to use. The support body, in fact, being sufficiently flexible, can be easily mounted around the rim and inside the tire.

The valve too is particularly easy to install and prepare for use, its being sufficient to use commonly available elements such as an Allen wrench or a ring-nut that can be tightened.