Safety valve for a container intended to contain a chemical or alimentary fluid

摘要

Pressure/vacuum relief valve for a vat containing chemical fluids or foodstuffs where the vacuum valve consists of a seat (20) with a central hole (36) on which there rests by gravity, a mobile plate valve (32) guided by a rod (82) which lifts under a vacuum in the vat. The design leaves no pockets in the valve housing which could cause a build up of contaminating products when being cleaned out. The valve (10) consists of a valve body (16) containing a lateral wall (18) which is closed at its top where it is fitted with a pressure relief valve and at its bottom is fitted a horizontal annular plate (20) holed in the centre (36) and whose upper face (24) defines an annular valve seat with which co-operates the mobile body (32) of the valve. This rests by the effect of gravity on the face of the valve seat (24) and is able to lift in the presence of a vacuum. The annular plate (20) forms a fixed assembly with the lateral skirt (18) and the central hole (36) of the annular plate and the mobile valve body (32) are oval or elliptical in shape to allow the body to be introduced upwards through the central hole (36) in the annular plate (20). The mobile valve body is guided by a central axial rod (82) to which it is fixed. This rod slides axially in a collar 88) attached to the underneath of the annular plate (20).