The present invention relates to a valve for swimming and diving respirator, like, as an example, a snorkel, to be attached at the terminal opening of the same respirator. This valve is used to limit or prevent the entrance of water by closing said terminal opening when the same valve is submerged under the water.

In the field of swimming or diving equipment, respirators or snorkels are widely used. These devices usually consist of a soft and anatomically shaped interface device, for connecting the respirator to the user breathing tract, attached to a rigid tube, 35/40 cm long, having the function to keep its breathing opening above the water surface while swimming and to avoid, in normal conditions, the water entrance into the same tube. This solution is nevertheless ineffective in case of waves or diving of the user head .

In order to solve this problem the available devices are usually provided with valves closing the breathing opening which are placed outside the air duct of the respirator, thus requiring the use of floating elements provided with closure seals and acting against the breathing opening, said breathing opening being therefore placed downward an toward the water surface. Some available devices are also provided with floating closure elements which are attached to the respirator by means of articulated joints formed by arms, levers, hinges to facilitate the floating element displacement towards its closing position, independently from the user head position in the water.

Even if in some way efficient, these solutions still present several problems. The need of an efficient floating closure and of a breathing opening oriented downward and towards the water surface makes these devices bulky with consequent ergonomic problems. The use of a floating element held by articulated and hinged joints creates an effective risk of frictions and malfunctions and in particular of jamming or cracking in case of contact with sand or salt sediments, which are very common within the sea water environment. Furthermore, these devices are complex and made with a great number of component parts, which makes their manufacture difficult and expensive.

An object of the present invention is to provide a valve for swimming and diving respirator that does not reproduce the above mentioned problems.

An object of the present invention is thus to provide a valve for swimming and diving respirator that is reliable in its use and eliminates the risks of malfunctions due to friction caused by the contact with sand or salt sediments.

Another object of the present invention is to provide a valve for swimming and diving respirator that is simple and inexpensive to manufacture and to assemble .

To these ends, the present invention provides a valve for swimming and diving respirator comprising a chamber , connected by means of a duct to an interface device with the user's breathing tract, provided with a breathing opening, in contact with the outside environment, oriented, during use, upward and in a direction opposite to the water surface, and with a movable sealed wall , opposite to said breathing opening, responsive to the hydrostatic pressure differential between the opened side of the breathing opening and the external side of the same wall of said chamber .

Advantageously said movable wall of said chamber, is provided with a closure surface adapted to close the chamber breathing opening.

Advantageously said movable wall of said chamber is provided with a flexible portion and together with its closure surface is movable between an opening and a closing position of said breathing opening.

Advantageously said movable wall is a membrane made in rubber or elastomer.

The present invention further provides a swimming or diving respirator characterized in that its breathing duct is connected to said valve for swimming or diving respirator.

The present invention further provides a swimming or diving respirator comprising a snorkel, with a mouthpiece, connected to said valve for swimming or diving respirator.

The present invention further provides a swimming or diving respirator comprising a full-face, an oro- nasal or a nasal mask, as interface device with the user's breathing tract, connected to said valve for swimming or diving respirator.

Other characteristics and advantages of the present invention will appear more clearly on reading the following detailed description, with reference to the accompanying drawings, which are given by way of non-limiting example, and in which:

FIG. 1 is a diagrammatic view of an embodiment of a swimming or diving respirator in the form of a snorkel, with a mouthpiece, complete with the valve object of the present invention; FIG. 2 is a diagrammatic exploded view of the valve for swimming and diving respirator e object of the present invention;

FIG. 3 is a diagrammatic perspective sectioned view of said valve for swimming and diving respirator in the open position;

FIG. 4 is a diagrammatic perspective sectioned view of said valve for swimming and diving respirator in the closed position.

Fig. 1 shows the valve 1 for swimming and diving respirator which has its breathing opening 6 oriented, during use, upwards and in a direction opposite to the water surface

The valve 1 is connected to the terminal opening of a tube/duct 5 attached to a mouthpiece of a snorkel 2, mouth-piece which is the interface device for connecting the respirator to the user ^' s breathing tract .

In the same way the valve 1 for swimming and diving respirator may be connected to other type or respirators (not represented) provided with full-face, oro-nasal or nasal masks as user' s breathing tract interface devices.

Figs. 2 and 3 show in a more detailed way the valve 1 for swimming and diving respirator object of the present invention. Said Valve 1 advantageously comprises an upper body 3 inside which it is formed a chamber 4 connected to a duct, or snorkel tube, 5 attached to an interface device with the user' s breathing tract. Said chamber 4 is advantageously provided with a breathing opening 6, in contact with the outside environment, oriented, during use, upward and in a direction opposite to the water surface, and with a movable sealed wall 7, opposite to said breathing opening 6, responsive to the hydrostatic pressure differential between the opened side of the breathing opening and the external side of the same wall 7 of said chamber 4. Advantageously said movable sealed wall 7 is formed as a membrane made in elastomer provided with a central closure surface 9 adapted to close said breathing opening 6 and with a perimetral flexible portion 10 allowing the movable surface 7 to move from a rest position to a position in which the surface 9 closes the breathing opening 6. The movable wall/membrane 7 is further provided with a seat 11 adapted to receive a raised edge 12, of the upper body 3, surrounding the base of the chamber 4. The sealed assembly of the flexible wall/membrane 7 is completed by the rim 15 formed in the lower body 13 of the valve 1. The lower body 13 is further provided with an opening 14 allowing the water and the hydrostatic pressure to act against the external side of the movable wall/membrane 7.

In the operational condition shown in Fig. 3 the valve 1 is totally above the water surface. The movable wall/membrane 7 is in its rest position and the breathing opening 6 is opened thus allowing the user to breathe without restrictions.

Fig. 4 shows the operational condition in which, due to a wave or the user's head diving, the valve is submerged under water which, through the opening 14 of the lower body 13, acts against the external side of the movable wall/membrane 7. In this situation the air contained in the camber 4 exits through the breathing opening 6 thanks to the action of the hydrostatic pressure, action which creates a differential pressure between the two sides of the movable wall/membrane 7. This causes the membrane 7 to move towards and reach the position in which its surface 9 closes the breathing opening 6 thus preventing the water entrance into the breathing duct 5. It is to be noted that, in this situation, any attempt to inhale made by the user increases the pressure differential inside the chamber 4 and therefore maintain the closure of the breathing opening 6.

Naturally, the various elements described above can be modified by the person skilled in the art, without going beyond the ambit of the present invention. As an example the elastomer used for the membrane 7 might be chosen with a hardness suitable to properly allow both the flexion of its perimetral portion 10 and the closure of the breathing opening 6. In the same way the movable wall/membrane 7 and in particular different portion of the same might be manufactured with differentiated materials to change their weight or density and to change their hydrostatic behavior in order accelerate or delay the closure of the breathing opening 6 in relation to the overall dimensions chosen for the valve object of the present invention and in particular of the distance at rest between the surface 9 of the membrane 7 and the breathing opening 6.

Other variants and modifications can also be envisaged, without going beyond the ambit of the present invention, as defined by the accompanying claims .