Technical Field

The present invention relates to a coupling and valve assembly for inner tubes. As is known, tires are deformable enclosures, typically made of compound, which cover the rigid rims of bicycles, motorcycles and vehicles in general. Background Art

Tires are kept in the desired conformation, in which they are able to perform their functions, thanks to the air under pressure contained in a tubular compartment, directly or indirectly delimited by the tires themselves, possibly cooperating with the respective rims of the vehicle.

More precisely, while embodiment solutions are known (called "tubeless") in which the compartment is directly delimited by the deformable enclosure and by the rim, in other by now consolidated embodiments, the compartment is inside an inner tube, a tubular element intended specifically to cooperate with the tire. More in detail, and with specific reference to the bicycle sector, tires with inner tube can be divided into two categories, wherein they take on corresponding names: clincher and tubular.

In clinchers, the inner tube is housed in the space delimited by the rim and by the deformable enclosure itself, which in this case has a substantially annular open section. Conversely, in tubulars, the deformable enclosure is a kind of closed circular cross-section torus, which can thus accommodate the inner tube inside it.

It should be noticed, however, that sometimes in the art the term "tire" (of any type) identifies precisely the assembly consisting of the deformable enclosure (which takes the name of tire ply) and the inner tube (plus other accessory elements such as the tread applied externally on the enclosure) and not the deformable enclosure.

In any case, with each tire and the relevant inner tube is associated a respective valve assembly, designed to put the compartment in communication with the outside, making it possible to introduce air into the inner tube (or allow it to come out) and therefore to inflate the tire (or deflate it).

According to well-known procedures, the valve assembly comprises a main axial symmetrical body, crossed by a longitudinal duct and bound to the inner tube. More precisely, a first end of the body is embedded in the thickness of the inner tube, so as, in any case, to leave the corresponding end of the inner duct facing the inner compartment of the inner tube itself. The body extends radially outwardly, thus being able to insert itself into one or more holes (radially aligned) made along the rim, before coming out with a portion protruding outwards.

With the inner duct, the main body then puts in communication the compartment of the inner tube (onto which faces one end of the duct) with the outside (where the protruding portion is located).

Typically, at the protruding portion, the duct is enclosed by a piston supported by an internally hollow pin, which is in turn screwed on the body head, corresponding to the free end of the protruding portion.

The introduction of air into the compartment is obtained by causing the temporary displacement of the piston and by injecting air into the pin by means of a pump, to be engaged to the pin at the aforementioned head.

Such embodiment does however have several drawbacks.

During fitting, it is necessary to determine a stable coupling between the main body and the rim: this objective is obtained by screwing from the outside a threaded nut onto the protruding portion of the body, until this is forced against the outermost surface of the rim. This action simultaneously results in traction on the edge of the inner tube, which on the opposite side is pressed against the innermost surface of the rim and hence, overall, the desired blockage of the body on the rim is achieved.

At the end of the operations described above however, the protruding portion of the main body of the valve assembly has lengths from time to time different, inasmuch as such dimensional parameter depends on the size and on the transverse outline of the components involved, and in particular of the rim, variable according to the needs and/or choices of the manufacturers.

The impossibility of knowing and controlling beforehand the length of the protruding portion of the main body is, however, a very big drawback, especially when, after fitting, such dimensional parameter shows itself to be significant.

It has, in fact, already been seen that to inflate the tire, the user has to attach a pump to a pin located at the head of the main body, at the end of the protruding portion. Therefore, when the main body protrudes significantly from the rim, while the user is using the pump, he/she submits the body to stresses which, due to the raised arm, cause bending and twisting moments of high intensity which can cause breakages or undesired deformations.

Description of the Invention

The main aim of the present invention is to overcome the above-mentioned problems by making a coupling and/or a valve assembly which provides high stress resistance, preventing or at least limiting the risk of breakage or deformations.

Within the scope of this aim, one object of the invention is to make a coupling and a procedure which permit mounting a valve assembly on a tire with inner tube, while at the same time controlling the length of its protruding position, on the outside of the rim.

Another object of the invention is to make a valve assembly wherein the length of its protruding portion, outside the rim, can be predetermined and is not dependent on the size and shape of the rim, as well as on other parameters.

Another object of the invention is to make a structurally simple and versatile coupling and/or valve assembly, easily adaptable to any type of tire with inner tube and pump.

Not the least object of the invention is to make a coupling and a valve assembly which ensure high reliability of operation, low cost, safe application and which are easily obtainable based on elements and materials readily available on the market.

Yet another object of the invention is to provide a coupling and a valve assembly which adopt a technical and structural architecture alternative to those of assemblies of known type.

This aim and these and other objects which will become more evident in the following pages are achieved by a coupling according to claim 1, an assembly according to claim 8, and a method according to claim 10. Brief Description of the Drawings

Further characteristics and advantages of the invention will become more evident from the description of a preferred but non-exclusive embodiment of the coupling and of the assembly according to the invention, illustrated by way of a non-limiting example, in the accompanying drawings, in which:

Figure 1 illustrates the coupling and the assembly according to the invention, in an exploded axonometric view;

Figure 2 illustrates the coupling and the assembly of Figure 1 mounted on a tire, in a front elevation view;

Figure 3 illustrates the coupling and the assembly of Figure 1 sectioned according to a longitudinal plane, in a partially exploded view.

Embodiments of the Invention

With particular reference to the aforementioned figures, globally indicated by reference number 1 is a coupling for valve assemblies 100, which may be normally applied on tires A comprising an enclosure B (deformable) arranged so as to cover a rigid rim C of a vehicle.

It is important to point out forthwith how, in a standard application, the tire A is intended to cover rims C of bicycles, although it can be used for rims C of other vehicles.

More in detail, the coupling 1 (as well as the assembly 100) is used for enclosures B which, according to well-known procedures, cooperate with an inner tube D which delimits internally a substantially tubular compartment E, which can be filled with a pressurized gas (normally air).

It should be noticed that the tire A can identify both the enclosure B alone, and the enclosure B itself and the inner tube D with which it cooperates (and any other accessories).

In the bicycle sector, or in others still, the invention can thus find application for tires A (also known as "clinchers"), wherein the inner tube D is housed in the cavity delimited by the enclosure B, which in this case has an open annular cross section, and the rim C.

Furthermore, the coupling 1 and the assembly 100 can be validly used with tires A (also known as "tubular"), wherein the inner tube D is fully housed in the enclosure B, which in this case has a toroidal conformation and closed circular cross section.

The use cannot however be ruled out of the coupling 1 and/or the assembly 100 for different types of tires A and/or, as has been said, of vehicles without thereby falling outside the scope of protection claimed here.

According to the invention, the coupling 1 comprises a first substantially tubular element 2, which is crossed longitudinally by a first through channel 3, at least partially threaded.

The first element 2 can be anchored, with one of its first ends 2a, to the outer edge of the inner tube D, with radial orientation.

In fact therefore, as is apparent in particular from Figure 3, the first element 2 faces the compartment E inside the inner tube D with its first end 2a, and from there, it extends radially outwards.

Furthermore, the coupling 1 comprises a second substantially tubular element 4, which can be inserted from outside in at least one hole F provided along the rim C (and with which the first element 2 may be aligned).

The second element 4 is suitable for cooperation with a valve 101 (including of known type) which is at least comprised in the assembly 100 and which is able to selectively close a second through channel 5, which is provided longitudinally in the second element 4.

It should be forthwith specified that the protection claimed here re-comprises first of all couplings 1 wherein, as in the attached illustrations, the valve 101 is a separate component, distinct from the second element 4. In this case, therefore, the valve 101 is not part of the coupling 1 according to the invention but, as has been said, it is comprised in the assembly 100, in any case the subject of the present discussion.

Likewise, the scope of protection outlined here must certainly be understood to be extended to couplings 1 comprising the valve 101, in this case integrated in the second element 4, which may be of the kind which will be described in the next pages or even different, but in any case capable of preventing and selectively permitting the passage of air.

When the second element 4 is inserted in the hole F, the second element 4 itself, which is at least partially threaded externally, is screwable hermetically in the first channel 3 up to a predefined level (i.e. leaving a predefined longitudinal level of the second element 4 outside the hole F). Screwing up to the predefined level corresponds to a locking configuration (shown in Figures 2 and 3), in which a stop element 6 automatically prevents any further advancement of the second element 4 in the first channel 3.

It should be noticed how, following the screwing of the second element 4 in the first channel 3, the channels 3, 5 define a communication path (the only one) between the compartment E and the external environment, path which is selectively closed by the valve 101.

Thus, any exchange of air between the inner tube D and the outside environment is normally prevented, while by operating the valve 101 air can be introduced into the compartment E (or made to come out) to inflate the tire A (or deflate it).

Thanks to the decision to insert the second element 4 into the first channel 3 in a sealed way, the danger of air leaks is also avoided: the air contained in the compartment E can escape from the second channel 5 only on the opposite side to the first element 2, if this is allowed by the valve 101.

As already said, in the particular embodiment shown in the illustrations, the first channel 3 is threaded internally and the second element 4 is threaded externally and can be screwed in the channel 3; within the scope of this treatise, such characteristic is to be deemed as a technical equivalent of any embodiment wherein it is the second channel 5 which is at least partially threaded internally and it is the first element 2 which has an externally threaded portion, wherein therefore an inverted male/female coupling is achieved with respect to that shown in the illustrations and the second element 4 is screwed around the first element 2 and not inside it.

Because the screwing of the second element 4 can only take place up to a predefined level, chosen beforehand, at the same time the second element 4 protrudes outside the rim C by a fixed longitudinal level also determined beforehand, thereby forthwith achieving the intended object.

It should also be noticed that the rim C has an external lamina on which the hole F is made and an inner lamina on which an orifice G is made, aligned with the hole F.

In this case, normally, the first element 2 is chosen with such a length that it can be inserted in the orifice G (as in the example of the attached figures), although making it with a shorter length cannot be ruled out, without thereby falling outside the scope of protection claimed here.

In particular, in an embodiment of considerable practical interest, shown on the attached illustrations for illustrative and non-limiting purposes of the application of the invention, the stop element 6 is substantially constituted by an intermediate flap 4a, which has an enlarged transverse cross-section, of the second element 4.

As a consequence of the screwing of the second element 4 in the first channel 3, with the second element 4 itself inserted in the hole F, the flap 4a moves progressively closer to the rim C until it rests against an external surface of the rim C (along which the hole F is made) at the predefined level, wherein the enlarged transverse cross-section (chosen greater than the width of the hole F) prevents further advancements (screwing) for the definition of the aforementioned locking configuration.

In fact, therefore, the position taken in the locking configuration by the second element 4 with respect to the rim C and, above all, the length of its protruding portion, depend only on a geometric parameter easy to determine beforehand (regardless of the type of tire A), i.e. the distance between the intermediate flap 4a and the external head 4b of the second element 4, opposite the screwed part in the first channel 3.

It is worth pointing out how any conformation taken by the intermediate flap 4a with enlarged transverse cross-section is to be deemed included within the scope of protection claimed here.

Conveniently, in a choice of embodiment of considerable practical interest, also proposed in the attached illustrations, the intermediate flap 4a forms a sort of knurled ring, which can be easily tightened by a respective tool for the facilitated movement of the second element 4.

It should be noticed that, in order to obtain the desired seal between the second element 4 and the first channel 3, it may be enough to have the former complete a short screwing stroke, so as to engage some volutes of its threads with the respective volutes of the threads of the first channel 3.

In order to ensure an optimal seal, several additional solutions may be envisaged, in any case falling within the scope of protection claimed here.

For example, in a first embodiment illustrated by way of example and without being limiting, particularly in the attached Figure 3, the first element 2 comprises a sealing member 7 of the type of an O-ring (as shown on the attached illustrations that is), or the like. The sealing member 7 is accommodated in a circumferential groove 8 provided along the first channel 3, preferably (but not exclusively) at the second end 2b of the first element 2, opposite the first end 2a.

This way, at least in the locking configuration, and following the screwing of the second element 4 in the first channel 3, the desired hermetic coupling is achieved between the latter and an intermediate portion 4c of the second element 4, which is not threaded and is adjacent to a threaded end portion 4d (to allow screwing that is) of the second element 4.

In a different embodiment (or as an additional option for the previous embodiment), to ensure the optimum sealing of the coupling achieved with the screwing of the second element 4 in the first channel 3, at least one of the latter and the second element 4 is spread with a sealing substance, of the Teflon type (which is a registered trademark) and the like.

Following screwing, the sealing substance (whether Teflon, which is a registered trademark, or otherwise) completely fills even the smallest cavities that could eventually form between the threads of the second element 4 (of the end portion 4d) and of the first channel 3, also hindering the minimum passage of air and thus ensuring an optimum seal.

With further reference to the embodiment shown in the combined figures for illustrative and non-limiting purposes of the application of the invention, the first element 2 is substantially composed of a cylindrical sleeve, which can be embedded in the thickness of the outer edge of the inner tube D at the aforementioned first end 2a. The first end 2a is, however, kept facing the compartment E of the inner tube D (so as to allow the passage of air to inflate or deflate the tire A); furthermore, the first end 2a has an enlarged transverse cross-section, so that it can be more firmly retained by the edge of the inner tube D.

Usefully, the protruding portion of the second element 4, in the locking configuration, has an external circumferential groove 9, which is positioned preferably (but not exclusively) in the proximity of the intermediate flap 4a (obviously on the opposite side to the end portion 4d).

The groove 9 makes the invention more practical to use, as it allows coupling with a protective hood, which can be arranged so as to cover the second element 4.

It should be noticed that by simply changing the groove 9 (and hence with minimal modifications to the second element 4 and keeping the same first element 2) it is possible to adapt the coupling 1 to different types of caps or in any case prepare it for coupling with different structures, providing the invention with a high degree of versatility.

The subject of the present treatise (and of the scope of protection claimed here) is therefore also a valve assembly 100, intended for tires A which, as has already been seen, comprises an enclosure B arranged so as to cover a rigid rim C of a vehicle. The enclosure B cooperates with an inner tube D which internally delimits a substantially tubular compartment E, which can in turn be filled with a pressurized gas.

As regards the extension of the scope of application, and of protection, the same considerations are naturally valid expressed in the previous pages regarding the coupling 1.

According to the invention, besides a coupling 1 having one or more of the various peculiarities expressed in the preceding pages, the assembly 100 comprises a valve 101 for the selective closure of the second channel 5.

More precisely, such valve 101 is normally arranged so as to hinder the free passage of gas in the second channel 5 (and hence also into the first channel 3) so as to maintain the desired pressure value in the compartment E.

The valve 101 can also be selectively (and temporarily) deactivated in order to allow the introduction of gas in the compartment E (normally by means of a pump) and/or the exit of gas from the compartment E (simply by leaving the passage open and exploiting the difference in pressure with the outside environment).

It is best to specify that the assembly 100 according to the invention can first of all comprise (be marketed with) three distinct components, consisting that is of the first element 2, the second element 4 and the valve 101. In the same way, the assembly 100 may also provide (be marketed with) simply a first element 2 and a second component, wherein are integrated the second element 4 and a valve apparatus (of the type of valve 101), of which an example of embodiment, or also different, will be provided herein below.

In an embodiment of considerable practical interest, mentioned for illustrative and non-limiting purposes of the application of the invention, the valve 101 comprises a cylinder 102 which is crossed axially by a through duct. Thanks to an outer thread 103, the cylinder 102 can be screwed partially into the second element 4 (in the second channel 5, in turn partially internally threaded), on the opposite side with respect to the portion of the second element 4 designed for screwing into the first channel 3 (hence on the opposite side to the end portion 4d).

Within the cylinder 102 is therefore sliding a piston 104, which can be arranged so as to close the second channel 5 in at least one useful position. In the embodiment of the attached figures, this is made possible by the shape given to the terminal part of the piston 104, which replicates that of at least one piece of the second channel 5.

In the convenient position, the piston 104 is arranged in such a way that its terminal part is located in such a piece, thus totally obstructing the second channel 5.

The piston 104 is therefore selectively movable from the useful position in order to allow the introduction of gas in the compartment E and/or the exit of gas from the compartment E itself.

More in detail, as can be seen from the attached illustrations, the movement of the piston 104, which allows it to be extracted at least partially from the second channel 5, preferably takes place by means of a tang 105 of the piston 104 itself, which protrudes from the opposite side to the cylinder 102 and which is therefore kept easily accessible during use.

Besides the coupling 1 and the assembly 100, one subject of the present treatise (and of the protection claimed here) is also a method for fitting a coupling 1 for valve assemblies 100 (and also, as an obvious consequence, a method for fitting assemblies 100) on tires A. As has already been repeated several times, such tires A comprise an enclosure B arranged so as to cover a rigid rim C of a vehicle and cooperating with an inner tube D that in turn delimits internally a substantially tubular compartment E, which can be filled with a pressurized gas. As regards the extension of the scope of application and of the protection, the same considerations are once more valid expressed in the previous pages in relation to the coupling 1 and the assembly 100.

The method consists, in a phase a, of providing a first substantially tubular element 2, which is comprised within the coupling 1 and crossed longitudinally by a first through channel 3, which is at least partially threaded.

Subsequently, in a phase b, the method consists in providing a second substantially tubular element 4. The second element 4 is comprised within the coupling 1, is crossed longitudinally by a second through channel 5 and is suitable for cooperation with a valve 101, comprised within the assembly 100, for the selective closure of the second through channel 5.

The method also consists in a phase c, radially anchoring a first end 2a of the first element 2 to the outer edge of the inner tube D and, in a phase d, introducing from outside the second element 4 into at least one hole F provided along the rim C.

The method then consists in screwing hermetically the second element 4, which is at least partially threaded externally, in the first channel 3, to a predefined level, which corresponds to a locking configuration in which a stop element 6 automatically prevents a further advancement of the second element 4 in the first channel 3.

The method may further provide for a phase of coupling of the valve 101 to the second element 4 so as to complete the fitting of not only the coupling 1 but also of the assembly 100, on the tire A.

The fitting and operation of the coupling and valve assembly according to the invention have therefore already been substantially anticipated in the previous pages, and are in any case the following.

During the fitting phase, the coupling is prepared between the first element 2 and the inner tube D, being careful to embed the first end 2a of the first element 2 in the outer edge of the inner tube D, while at the same time maintaining the first end 2a facing the compartment E (so the latter can be in connection with the first channel 3).

Likewise, the second element 4 can be inserted from outside in the hole F.

It is pointed out that, depending on the shape of the rim C and its cross section in particular, the second element 4 is inserted not only in a single hole F but also in other orifices G aligned with it, in any case made along the rim C (as on the attached illustrations, which provide for an orifice G as well as a hole F).

Following the insertion of the second element 4 into the hole F, it is possible to proceed to screw the second element 4 in the first channel 3, previously aligned in turn with the hole F.

The screwing can thus continue as long as the stop element 6 does not prevent further advancements: as has been seen, this occurs when the intermediate flap 4a rests (abuts) against the external surface of the hole F.

It should be noticed that reference has always been made to rim C, but it is intended as included in the scope of protection claimed here the possibility that the intermediate flap 4a and the other components involved refer to other surfaces associated with the rim C.

With the aforementioned resting, the locking configuration is obtained, wherein the compartment E communicates with the outside (only) thanks to the second channel 5 aligned with the first channel 3.

Notice how, in such locking configuration, the constraint between the first element 2 and the second element 4 is stable (taking care to tighten the second element 4 by causing the intermediate flap 4a to press against the external surface of the rim C). Thus, the intermediate flap 4a and the threaded coupling between the elements 2, 4 prevent any reciprocal movement between the latter. It is once more reiterated that, in any conformation of the rim C and/or of the type of tire A, once fitting is finished, the second element 4 protrudes externally by the same length, univocally determined by the distance between the intermediate flap 4a (resting on the external surface of the rim C) and the head 4b.

It should also be noticed how on the opposite side the end portion 4d can be chosen of the desired length, no particular geometrical or constructive constraints existing in this regard. It is in fact sufficient that the end portion 4d be able to fit in the first element 2 (to ensure the seal). It should be observed how the building is envisaged of an inner shoulder 3 a along the first channel 3, to delimit the threaded part of the latter, as shown on the attached illustrations. In this case, for any possible size and shape provided for the rim C, the only care that will have to be taken will be to arrange the shoulder 3a so as to in any case allow screwing the end portion 4d in the first channel 3 in such a way that the intermediate flap 4b can properly perform its function (preventing further advancements once the predefined level has been reached) before, that is, the shoulder 3a can in turn interfere with screwing.

As has already been seen, the passage of air is regulated by the valve 101, which couples with the coupling 1 at the head 4b of the second element 4, protruding externally, where a pump must also be fastened (according to procedures known in themselves) whenever the tire A is to be inflated.

While therefore the single body present in the known valve assemblies (replaced in the assembly 100 by the coupling 1) protrudes externally with one of its segments different from time to time, depending on the shape of the rim C and on its dimensions, this is not the case using the coupling 1 according to the invention.

For large rims C, suffice it to increase the distance between the intermediate flap 4a and the head 4b appropriately, without further modifications. It is therefore possible to size the second element 4 so that it protrudes by the desired length, enough to allow practical coupling with the pump (or other devices) but not so high as to determine a significant lever arm and therefore dangerous bending or torque moments, when the user, that is, couples the pump to the valve 101 and/or to the second element 4.

The intended object is thus achieved, inasmuch as it is possible to size the second element 4 in such a way as to avoid the risk of subjecting the coupling 1 and the assembly 100 (and the second protruding element 4 in particular) to excessive stresses, breakages or undesired deformations.

It has also been shown that the coupling 1 and the assembly 100 are undoubtedly versatile, and can be used or most easily adapted to any type of tire A with inner tube D, and of pump. Moreover, the solution presented here is undoubtedly structurally simple, since the coupling 1 is made up only of the elements 2, 4 (to which must be added a valve 101 to complete the assembly 100).

The invention so conceived is susceptible to numerous modifications and variants all falling within the scope of the inventive concept; moreover, all details can be replaced with other technically equivalent solutions.

In the examples of embodiment shown, the individual characteristics, shown in relation to specific examples, may in fact be replaced with other different characteristics, existing in other examples of embodiment.

In practice, the materials used, as well as the dimensions, can be any according to requirements and the state of the art.