Abstract:
The valve, which is intended to regulate the passage of a fluid through an office [(O)] in a wall [(P)], comprises a tubular body [( 10 )] and a flexible rubber cover [( 11 )] which deforms under the action of the pressures [(P 1  and P 2 )] prevailing in the spaces on each side of the valve.

Description:
TECHNICAL FIELD 
     The present invention relates to a universal valve allowing regulation of the flow of a fluid, liquid or gas, e.g. air, water, oil, blood, etc., through an orifice in a rigid, semi-rigid, flexible etc. wall delimiting spaces in which there prevail respectively pressures P 1 , P 2 , the valve having a tubular body intended to be fixed in a sealed manner facing the orifice on one side of the wall, and a deformable flexible member subject to the action of the pressures P 1  and P 2  controlling the flow of the fluid as a function of these pressures. 
     BACKGROUND OF THE INVENTION 
     The document DE 387 190 relates to a valve for a sealed envelope of a ball, comprising a conical tubular body fixed to the internal wall of the envelope, on the inside of which is mounted a seal having a conical concave part, within which there engages a likewise conical central part. The conical concave part has holes which are sealed by the conical tubular body and by the conical central part of the seal when the pressure inside the envelope is greater than the external pressure. 
     The document EP-A-0 253 748 relates to a one-piece valve, the thickness of which matches that of the wall of an enclosed space to be isolated, the said valve having an internal cavity which communicates with the exterior via a first hole and communicates with the interior of the enclosed space via a plurality of holes arranged between the wall of the enclosed space itself and a part of the latter forming a valve element, these holes being closed when the pressure inside the enclosed space is greater than the external pressure. 
     The document DE-A-2 062 116 relates to a nonreturn valve for a pneumatic control valve comprising a body into which there open an inlet for fluid under pressure, an outlet towards a consuming unit and a vent. A valve element is mounted so as to slide in the control valve to allow either the consuming unit to be fed from the pressure source, with the vent being closed, or to vent the consuming unit, with the inlet for fluid under pressure being closed. 
     SUMMARY OF THE INVENTION 
     The valve according to the invention is defined by the characteristic given in claim  1 . 
     Its principal quality is that it has very low inertia while at the same time being highly reliable. 
     It is universal in the sense that it has applications and uses in various sectors, e.g. in pneumatic objects and devices (boats, balls, mattresses, buoys, etc.), in medicine and surgery (artificial hearts), in aeronautics, in sporting equipment (diving etc.). In principle, there are no particular problems in miniaturizing it. 
     Other characteristics of the invention will emerge from the subclaims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The attached drawing illustrates, schematically and by way of nonlimitative example, two embodiments of the subject matter of the invention in the case of its application to a valve integrated into the envelope of a pneumatic device: 
     FIGS. 1 to  3  are three sectional views of the valve and the part of the envelope on which it is mounted, when the internal and external pressures are equal, when the external pressure is greater than the internal pressure and when the internal pressure is greater than the external pressure respectively; 
     FIG. 4 is a view similar to those in FIGS. 1 to  3  illustrating mechanical control of the outflow of air through the valve; 
     FIG. 5 is a sectional view of a variant embodiment of the valve in FIGS. 1 to  4 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The valve illustrated in FIGS. 1 to  4  is described as an integral part of the flexible envelope of a ball used in sport (football, basketball, etc.) or a pneumatic tyre for a vehicle (motor vehicle, aeroplane etc.) with or without an air chamber, the inflation pressure in this equipment being of great importance. 
     This valve is formed by a rigid, semi-rigid or flexible tubular body  10  bonded to the internal surface of an envelope P coaxially to the inflation orifice O, and by a cover  11  made of flexible rubber housed in a frustoconical cavity  12  of the body  10  and bonded to the latter at the level of circular bearing surfaces  13  arranged at the edge of a dished part situated at one end of the core  14  of the cover  11 . The other end of the core is provided with a dished part  15 . 
     In the case shown in FIG. 1, the pressures P 1  and P 2  are equal to atmospheric pressure (P 1 =P 2 =P at .) and the circular edge  16  of the dish  15  is pressed against the circular surface of the fillet connecting the frustoconical wall  17  and the upper surface  18  of the cavity  12 . 
     The body  10  and the cover  11  delimit two zones A and B, zone A communicating directly with the orifice O and zone B being connected by holes  20  to the interior of the envelope P. The air cannot circulate in either direction. 
     When P 1 &gt;P 2  (FIG. 2, inflation of the ball), the air drawn in through the orifice O exerts an effect on the dish  15  which brings about elastic deformation of the cover  11  and opens a circular passage f between the edge  16  and the wall  17 . The air can flow from the outside to the inside of the ball and inflate it. 
     When P 2 &gt;P 1 , (FIG.  3 ), the cover  11  is subject to an upward action which deforms it elastically, pressing the surface  19  of the dish  15  against the surface  18  and closing the passage f. 
     It will be observed that during the deformations of the cover  11  illustrated in FIGS. 1 to  3 , the edge  16  of the dish  15  is displaced in the axial direction. When it proves necessary to reduce the pressure P 2  in the case where P 2 &gt;P 1 , some of the air trapped in the ball can be allowed to escape to the outside by introducing a pin L into the orifice O and exerting a mechanical action on the surface  19 . The balloon continues to deflate for as long as this action is maintained. It will be stopped when the pressure P 2  has reached the desired value. 
     In the variant in FIG. 5, in which the valve is in three pieces, the cover  11  has the shape of a diabolo, having a dish intended to be supported against the base  10 A of the tubular body  10 B and a second dish intended to be supported against the closing wall of the tubular body. This closing wall has, on the one hand, holes  20  for connecting the annular cavity delimited by the frustoconical wall of the tubular body  10 B and the core of the cover  11  to the space at the pressure P 2  and, on the other hand, a hole  21  for connecting the space within the second dish to the space at the pressure P 2 . 
     By appropriate choice of the material and the dimensions of the cover  11 , it is possible to construct a valve which, apart from being extremely reliable, will have a very sensitive response combined with very low inertia. 
     It is possible to inflate pneumatic objects and devices with relatively low-pressure pumps or even by mouth. The invention is obviously not limited by the above text and the attached drawing. 
     In particular, the cover  11  may take forms very different from those shown while remaining within the scope of the claims, the essential element being that it deforms elastically under the action of the pressures P 1  and P 2  in such a way as to open or close a passage f between the spaces  1  and  2  on each side of the valve. 
     Moreover, the valve according to the invention can easily be miniaturized. 
     Finally, provision can be made to give the frustoconical wall  17  a special profile such that, as it is displaced axially towards the inside, the edge  16  of the cover  11  exposes passages of relatively large section so as to rapidly increase the air flow rate. In particular, the wall  17  can have grooves from a certain level onwards.