RELIEF VALVE

Abstract: Relief valve (6) including a valve body (5) where the covering disk (1) holding the seal membrane (2) is completely built in. The axial dimensions of the valve coincide with the thickness of the valve body (5) and the upper surface of the relief valve is flat. The application of the valve does not modify the external appearance of the container as the faying surface is also flat.

Description: RELIEF VALVE FIELD OF TECHNOLOGY This invention refers to the packaging technology generally included in the international classifications B 65 b / B 65 d. STATE OF TECHNOLOGY Different solutions related to relief valves are now technically known, especially those described in the German patents: 2360126 3125496 3147321 111935 1195830. The solutions described in these patents do not completely face physical and functional problems of relief valves; they just make a compromise as they do not solve all the following problems: - too high thicknesses causing deformations on the packaged product - too high diameters causing difficulties when handling flexible material where the valve has been applied - during thermo-welding, the application of the valve may come up against further difficulties if not carried out with sufficiently soft material - the insertion of valves into an already punched bore may present centering difficulties. Other problems concern external appearance, tampering and stacking difficulties of packages; others refer to external valves or to interaally- t , applied valves which protude because of their shape and can all jeopardize * the good operation of the valve, thus endangering the quality of the packaged product. The overall solution to all these difficulties is the carrying out of a flat valve of reduced dimensions and designed so that it can be made by soft material. This new valve does not require the previous punching of the insertion bore on the flexible belt and it eliminates the related centering operations. Indeed the valve is directly placed on the non-punched belt and during its application it acts as a counter-plate for the simultaneous relief bore. DESCRIPTION The invention is now presented with reference to the enclosed drawing as a non-limiting example. Figure 1 represents schematically the valve applied inside a container in relief position. Figure 2 represents the same valve in seal position against air penetration from outside. Figure 3 illustrates the valve in details as follows: 1 covering disk 2 seal membrane disk inclined edge disk groove valve body axial thickness of relief valve upper surface of covering disk upper surface of valve body 9 flexible container 10 disk central bore 11 disk ribs 12 membrane seal seat 13 valve body bores 14 seal viscous layer 15 relief bore drilled in the container From Figure 1 we can see that the relief action is due to the lifting of the membrane (2) from the related seal seat (12) and to the presence of ribs (11) of the disk (1). Under particular conditions of inner overpressure, gases to be eliminated pass through bores (13), lift the membrane (2), flow through ribs (11) and go outside through bores (10 and 15). From Figure 2 we can see that the seal action is due to the adhesion of the membrane (2) to the seat (12) of the valve body. This action is optimized by the presence of the viscous layer (14) which ensures the hermetic seal of the container after relieving. The invention is obviously susceptible of different forms of carrying out and choices of manufacturing technologies. All the relief valves carried out with the described, illustrated and later claimed characteristics are thus part of this protected industrial patent right.

Claims: CLAIMS: 1) Relief valve characterized by the fact to be made by a circular disk (1) covering the membrane (2) fitted by means of its inclined edge (3) in the corresponding groove (4) on the valve body (5) on whose seal seat (12) the membrane (2) rests and whose seal is ensured by the viscous layer (14). 2) Relief valve, as in the previous claim, characterized by the fact that its axial dimensions (6), with the covering disk (1) completely built in the valve body (5), coincide with the thickness of the valve body and the upper surface (7) of the covering disk (1) is at the same level as the upper surface (8) of the valve body (5). 3) Relief valve, as in the previous claims, characterized by the fact that, if applied inside a flexible container (9), does not modify the external appearance as the faying surface is flat. 4) Relief valve, as in the previous claims, characterized by the fact that the covering disk (1) has a central bore (10) for gas passage and acts as a counter-plate during the drilling of the relief bore (15) on the wall of the flexible container (9). 5) Relief valve, as in the previous claims, characterized by the fact that the covering disk (1) presents protruding ribs (11) to allow the flow of relief gases from the upper surface of the membrane (2) to the lower surface of the disk (1).

Inventors: RAPPARINI GINO, RAPPARINI, GINO
Applicants: ICA SPA, ICA S.P.A.
Application year: 1992
Main classification: B65D77
IPC codes: B65D77, F16K17