Ball valve device and method for forming a ball retainer in a check valve

Abstract

The ball valve device comprises a tubular body in metal material, having a cylindrical wall conformed with spherical cup-shaped internal protrusions to retain a ball shaped valving member, preventing the same valving member from being entrained by a fluid flowing through the valve device. The internal spherical protrusions are formed by radially pressing and crimping the cylindrical wall of the tubular body at one or more angularly spaced apart deformable areas of an annular strip. The tubular body provided with the ball retaining protrusions is suitable for any valve device, such as ball check valves, pumping units, and/or ducts.

1 . A method for forming a ball retainer in a valve device, in which the valve device comprises a tubular body having a cylindrical wall and an inner surface; and in which the cylindrical wall is provided with at least one internal protrusion to stop a movable ball-shaped valving members, the method comprising the steps of:
 defining at least one deformable area for the formation of the internal protrusion on an annular strip of said cylindrical wall;   shaping the internal protrusion by radially deforming and crimping the cylindrical wall at said deformable area of the tubular body;   conforming the cylindrical wall with at least one cup-shaped internal protrusion having an inner spherical surface; and   merging the inner spherical surface of the cup-shaped protrusion to the inner surface of the cylindrical wall, by a concave annular surface.   
     
     
         2 . The method according to  claim 1 , comprising the step of positioning a removable internal plug member, into at least one end of the tubular body, to prevent the deformation of said one end during crimping of said at least one internal cup-shaped spherical protrusion at a deformable area of the cylindrical wall. 
     
     
         3 . The method according to  claim 2 , wherein the internal plug member extends up to an end edge of said annular strip. 
     
     
         4 . A ball valve device comprising a tubular body, having a cylindrical wall axially extending between inlet and outlet ends, the cylindrical wall being conformed with at least one internal cup-shaped projection having an inner spherical surface, the cylindrical wall of the tubular body being provided with an annular flange member at inlet and outlet ends;
 a valve connecting member at each of said inlet and outlet ends, provided with a corresponding annular flange member;   and clamping means for clamping the annular flange members of the tubular body, to the annular flange members of the valve connecting members.   
     
     
         5 . The valve device according to  claim 4 , in which the inner spherical surface of the cup-shaped spherical protrusions is merging with an internal surface of the tubular body, by a concave annular surface having a curvature radius equivalent to the curvature radius of said cup-shaped protrusions of the body of the valve device, or up ±10% of the curvature radius of the same cup-shaped spherical protrusions. 
     
     
         6 . A pumping unit comprising at least one pumping chamber having inlet and outlet sides for a fluid, wherein at each of said inlet and outlet sides the pumping unit comprises a check valve conformed according to  claim 4 . 
     
     
         7 . The pumping unit according to  claim 6 , comprising in a double acting diaphragm pump.