Flow control valve with device for indicating the status of a fluid, particularly for gas containers

1. A flow control valve with means for indicating the status of a fluid, particularly for gas containers, comprising a valve body provided with an end on which a threaded shank is provided for hermetic coupling to a gas container, and a handwheel, a gas status indicator device being comprised within the handwheel, said handwheel forming a casing of said device, said device comprising a plunger that is constituted by a head and by a helical stem that is engaged in a cavity of a rotatable body that can rotate so that an axial movement of said plunger is matched by a rotation of said rotatable body, which has a visible portion that is marked so as to provide an indication of the status of the plunger, which can move axially, in opposition to a force exerted by a calibrated spring, between at least one minimum position, in which said head abuts against a shoulder, due to the action of said calibrated spring, and a maximum position, in which said plunger abuts against an end of said rotatable body, said plunger being rotationally fixed to said handwheel so that said device rotates with said handwheel, said handwheel having a cavity that accommodates said plunger and said rotatable body.

2. The valve according to claim 1 , comprising a region that provides a hermetic connection to the user device supply system.

3. The valve according to claim 2 , comprising a first feed duct is formed inside said shank and a second feed duct is formed inside said region for connection to the user devices, said ducts allowing the passage of the fluid that arrives from said container and is directed toward the user devices.

4. The valve according to claim 3 , wherein said ducts are connected through a passage that is formed in the region where they intersect.

5. The valve according to claim 4 , wherein said valve body has a region inside which a piston portion of said handwheel is accommodated, said piston forming a movable closure member that is capable of passing from an open position, in which said ducts are mutually connected through said passage, and a position for flow control or closure, in which said passage is no longer provided, interrupting the connection between said ducts, and vice versa.

6. The valve according to claim 5 , wherein said movable closure member can slide within the body by means of a threaded coupling.

7. The valve according to claim 6 , wherein said movable closure member comprises a flow control portion, which closes said passage hermetically, by means of a gasket, obstructing said passage and preventing the flow of the fluid contained in the container toward the second feed duct.

8. The valve according to claim 1 , wherein the movement of said plunger is opposed by said spring, which is mounted coaxially to the stem so as to push the head of the plunger into abutment against said shoulder, said shoulder being formed along an axial chamber of said cavity.

9. The valve according to claim 8 , wherein said axial chamber is connected to said ducts by a radial channel.

10. The valve according to claim 9 , wherein said rotatable body can rotate inside said cavity, which is closed in an upper region by a transparent dome.

11. The valve according to claim 10 , wherein the pressure that is present in the ducts determines the position of the plunger in an axial direction, said plunger having two extreme positions, one for pressure below a certain limit, in which said spring pushes said head into abutment against said shoulder, and one for maximum pressure, in which said head abuts against the end of the rotatable body.

12. The valve according to claim 11 , wherein the measurement of the pressure inside the ducts lies within an interval that depends on the calibration of the spring.

13. The valve according to claim 12 , further comprising two annular gaskets above the channel, between the handwheel and the valve body, in order to isolate an upper part of the handwheel.

14. The valve according to claim 13 , further comprising a tangential pin, which is accommodated in a groove formed inside the valve body and is adapted to limit the movement of the handwheel between the fully open position of the valve and the closed position.

15. The valve according to claim 1 , wherein a pressure delta within which the device operates is determined by calibrating the spring.