A valve for gases, having two consecutive and independent stages:
- a first stage and a second stage wherein the second stage comprises:
- an inlet passage and an outlet passage for the gas between which a primary volume (V) is defined;
- at least one shutter interposed between the inlet passage and the outlet passage and movable along a movement direction (L) between an open position, in which it allows the flow of the gas from the inlet passage to the outlet passage, and a closed position, in which it prevents the flow of the gas;
- an actuator of the shutter comprising an electromagnet adapted to generate a variable magnetic field and a magnetic element associated with said shutter and movable along said movement direction (L) as a function of the magnetic field generated by said electromagnet for moving the shutter at least from the closed position into the open position or vice versa;
- a separation membrane interposed between said shutter and said fixed portion of the valve to separate said primary volume (V) from a secondary volume (W) arranged along the movement direction (L);
- said separation membrane being conformed to expose an active wall to the fluid present between the outlet passage and the shutter;
- and
- a stabilisation membrane arranged by snap-fitting into the second volume (W) for splitting it into an auxiliary volume (U) and an intermediate volume (Y);
- said intermediate volume (Y) being comprised between the separation membrane and the stabilisation membrane for containing a fluid at a pressure substantially equal to the atmospheric pressure value,
- wherein said actuator comprises an actuating shaft extending along the movement direction (L) from a first end connected to said magnetic element towards an operating end arranged in said primary volume (V) and associated with said shutter,
- wherein the separation membrane has a connecting portion arranged between said edge of said tubular body and said fixed portion,
- wherein a first stage comprises a further shutter arranged in the primary volume (V) and movable along the movement direction (L) between a flow position, in which it allows the passage of the gasses towards the shutter, and a locked position, in which it prevents the passage of the gasses;
- and wherein said actuating shaft is common to both shutters and is configured to move them independently with respect to one another, and
- wherein said actuator comprises a tubular body at least partially interposed between said electromagnet and said magnetic element;
- said electromagnet being arranged in a static position with respect to a fixed portion of the valve and said ferromagnetic element being slidably inserted in said tubular body for moving along said movement direction (L) as a function of the magnetic field generated by said electromagnet;
- said tubular body being made of non-magnetic material.