Description

Connection pipe for pressure transfer from deflated to inflated tyres.

The present patent application relates to a extensible connection pipe used as accessory for cars or motorcycles to transfer pressure from one tyre to another in case of deflation.

As it is known, owners of cars and motorcycles sometimes face the problem of a deflated tyre - for accidental reasons or vandalism acts - during a journey or after a stop, far away from a mechanical shop with suitable tools.

Users who have found themselves in such a situation know very well the discomfort and problems caused by this inconvenience.

If possible, the user must replace the deflated tyre with a spare tyre. If the spare tyre is not available (such in the case of motorcycles or in case of cars with more than one deflated tyres) the user will be forced to call for breakdown service.

It must be said that some attempts have been made in the past to remedy the foregoing inconvenience. Small spray cans with compressed air have been introduced on the market to provide for partial inflation of tyres with reduced pressure.

Nevertheless, the said spray cans are rather expensive and have an expiration date after which perfect functional efficacy is not guaranteed.

Alternatively, small compressors powered by the car battery have been used to restore the correct tyre pressure.

These compressors are impaired by high cost and considerable volume (which prevents them from being installed on motorcycles); moreover, they can be only used in cars and motorcycles provided with 12Volts socket.

The purpose of the present invention is to devise a tool to be used as an alternative to the aforementioned spray cans and compressors, provided with basically the same function and characterised by high practicalness.

The present invention is based on the physical principle of communicating vessels in order to transfer pressure from one or more

perfectly inflated tyres to a deflated tyre.

The said operating logic principle has been implemented by means of an extensible connection pipe, preferably a spiral one (same as the one used for compressed air in mechanical shops), with suitable length to cover the maximum distance between the wheels of the vehicle.

The ends of the said connection pipe are provided with nozzles similar to the ones used by tyre repairers to inflate tyres; each nozzle is inserted into the mouthpiece used to inflate the tyre in order to open the traditional oneway needle valve. In case of a deflated tyre, the user must remove the plug of the deflated tyre and the plug of a second inflated tyre.

Now, he must insert the first end of the connection pipe of the invention into the mouthpiece of the deflated tyre and then insert the second end of the connection pipe into the mouthpiece of the inflated tyre. This creates direct communication between the internal inflatable cavity of the deflated tyre and the internal inflatable cavity of the inflated tyre; the principle of communicating vessels favours the spontaneous transfer of compressed air from the inflated tyre to the deflated tyre, which ends when the two tyres have reached the same inflation pressure. After such an operation, the two tyres have a lower pressure than the recommended value; however, the important thing is that the vehicle is now able to resume the journey, keeping in mind that the inflation pressure is not at the recommended value.

Once transfer is completed, the user must remove the connection pipe of the invention and replace the plugs on the mouthpieces of the two tyres.

The said operation must be carried out carefully in order to prevent the first end from disengaging from the tyre, thus causing the uncontrolled emission of air from the tyre where the second end is engaged.

To that end, the connection pipe of the invention is provided with a cock to interrupt the air flow between the two ends.

The cock must be closed as soon as the transfer of compressed air between the two tyres is completed, before disengaging the nozzle from the

mouthpiece of the tyre.

Preferably, the said cock must be installed immediately upstream the nozzle of the connection pipe of the invention, it being provided that in this case the nozzle is removed from the tyre after removing the opposite nozzle, after closing the said cock.

According to a simplified embodiment, the connection pipe of the invention is not provided with the said cock used to intercept the air flow.

In this case, the user can avoid the uncontrolled emission of air from the tyre from which the connection pipe is disengaged by simply bending a section of the said pipe, thus choking the pipe to obstruct the free passage of compressed air and act as a stop valve.

The connection pipe of the invention is provided with another technical feature to optimise the operation mode.

The said features prevents a risk that may occur in case of negligent use of the pipe of the invention.

In fact, the pressure drop in the tyre may not be caused by a puncture, being the result of tyre unbeading or chapping in hidden parts that are not visible for the user.

In this case the use of the connection pipe of the invention would be counter-productive, since it would prevent inflating the tyre with reduced pressure, and cause the complete deflation of the tyre with normal pressure.

Such a lamentable phenomenon would be produced because the air introduced inside the unbeaded or chapped tyre is immediately dispersed in the atmosphere through the large passage sections created in the tyre by the structural damage.

In such a case, because of the communicating vessels, the transfer of pressurised air from the inflated to the deflated tyre would end only when the inflated tyre has lost pressure completely.

Because of the aforementioned technical feature, the connection pipe of the invention is able to prevent such an inconvenience.

To that end, the nozzle of the pipe designed to be inserted in the inflated tyre is provided with a special needle valve subjected to the action of

a precompressed spring that constantly tends to push the needle in the closed position.

In such an operating position, the needle is moved forward towards the inlet hole of the adjacent nozzle, thus obstructing the passage section of the connection pipe of the invention and preventing the air transfer from one end to the other end of the pipe.

The needle valve is designed to lose its closed position as soon as the adjacent nozzle is inserted into the mouthpiece of the inflated tyre.

In such a way, an energetic flow of compressed air is introduced into the said nozzle, moving the needle backwards to win the resistance of the spring, freeing the passage section of the pipe and allowing for air transfer from the inflated to the deflated tyre.

Evidently, the pressure of the air flow that penetrates the pipe of the invention tends to decrease with the gradual deflation of the inflated tyre. The adjustment of the spring associated with the needle valve avoids the risk of uncontrolled complete deflation of the inflated tyre in case of unbeading or chapping of the other tyre.

To that end, the spring of the valve is adjusted in such a way as to automatically bring the needle back to the closed position as soon as the pressure of the air flow from the inflated tyre decreases to a value of approximately 1 bar (at least when the pipe of the invention is used on tyres of ordinary cars).

In this way, the air contained in the inflated tyre is not dispersed completely in the presence of total seal loss in the other tyre due to unbeading or chapping not detected by the user.

In this situation, the user will have to replace the unbeaded or chapped tyre, but will be able to use the other tyre, although partially deflated, to carefully drive the vehicle to the nearest service centre.

To ensure the easier and safer use of the pipe of the invention, the nozzle that cooperates with the needle valve has a different colour from the nozzle provided at the opposite end.

In this way, the user can identify the nozzle to be inserted on the

inflated tyre and the nozzle to be inserted on the tyre with reduced pressure.

It must be noted that the aforementioned technical feature is efficacious also when the needle valve is situated along the pipe near the nozzle to be inserted in the inflated tyre, rather than at one of the nozzles. Finally, in order to additionally improve the practicalness of the connection pipe of the invention, the nozzles are provided with a lever (of the type used in the nozzles of traditional compressed air pipes used to inflate tyres) designed to maintain the stable connection with the mouthpiece of the tyre during the entire air transfer operation. For purposes of clarity, the description of the invention continues with reference to the enclosed drawing, which is intended for purposes of illustration only and not in a limiting sense, whereby:

- fig. 1 is a view of the connection pipe of the invention in operating position, when air is transferred from a inflated rear tyre to a deflated front tyre; - fig. 2 is a diagrammatic sectional view of the structure of the needle valve designed to be installed in the proximity of a nozzle of the pipe.

With reference to the said figures, the present invention consists in a connection pipe (1 ), preferably provided with elastically extensible structure, which is provided at the two ends with nozzles (2a, 2b) of known type, designed to be inserted into the mouthpieces of the tyres to open the corresponding one-way valves.

Each nozzle (2a, 2b) is provided with a lever designed to ensure the stable connection of the nozzle with the mouthpiece of the tyre.

With reference to fig. 2, the first nozzle (2a) - that is to say the one designed to be inserted into the inflated tyre - cooperates with a special oneway valve (20).

In particular, the said valve (20) is provided with a needle (21 ) subjected to the action of a precompressed spring (22) designed to constantly push the needle (21) forward to a position in which the needle (21 ) ensures the complete obstruction of the passage section (10) of the pipe (1 ).

The needle (21 ) is designed to be moved backwards, thus losing its closed position, when the air flow that penetrates from the inflated tyre inside

the pipe (1 ) has a suitable pressure value to overcome the force of the spring (22).

Preferably, the valve (20) is provided with means (not shown in fig. 2) that allow for adjusting the spring (22). These means allow to adjust the operation of the spring (20) according to the different conditions of use of the connection pipe of the invention (1) for car tyres or lorry tyres (that is to say tyres with different operating pressure).

In any case, as soon the pressure of the air flow decreases below a predefined threshold value, which corresponds to the adjustment of the force of the spring (22), the spring (22) pushes the needle (21 ) forward and prohibits the passage of the air from one end to the other end of the pipe (1 ). Another feature of the pipe of the invention (1) consists in a manually actuated clock (3) designed to intercept the flow of compressed air in the pipe (1 ) installed in intermediate position between the two nozzles (2a, 2b). Preferably, the cock (3) is installed immediately upstream the second nozzle (2b), that is to say the one designed to be inserted into the tyre with reduced pressure.

The cock (3) is brought in closed position by the user before removing the connection pipe of the invention (1) after completing the transfer of compressed air from the inflated to the deflated tyre.

The nozzles (2a, 2b) have different colours for immediate identification, being designed to be inserted in the inflated tyre and in the tyre with reduced pressure, respectively.