Valve for methane in automotive systems with by-pass system of the excess flow blocking device
A valve ( 1 ) controlling flow of methane gas in automotive systems includes a feed duct ( 30 ) of the gas to the delivery duct ( 20 ); having a by-pass duct ( 32 ) delimited by a by-pass duct ( 34 ) internal to the tank duct ( 6 ), to limit the overall dimensions in the attachment area to the tank.
1. Valve for controlling flow of methane in automotive systems, the valve being adapted for a tank and comprising:
a valve body including a tank duct ending in at least one main aperture, an entry duct, a delivery duct and a discharge duct;
a thermal safety device, operating between the tank duct and the discharge duct and normally closed to obstruct passage of methane between the tank duct and the discharge duct, adapted to switch to an open configuration if external temperature exceeds a predefined threshold value;
a blocking device, operating upstream of the delivery duct, adapted to switch to a closed configuration in which the blocking device chokes the passage of methane towards the delivery duct if the flow of methane exceeds a predefined threshold value, and normally open, the blocking device being positioned upstream of the main aperture of the tank duct;
a feed duct fluidically separate from the tank duct, connectable downstream with the delivery duct;
wherein the blocking device is operative upstream of the feed duct and is responsive to the flow of methane through the feed duct, and
wherein the feed duct comprises a by-pass duct inside the tank duct.
2. Valve according to claim 1 , wherein the by-pass duct is delimited by a tube housed in the tank duct.
3. Valve according to claim 2 , wherein the tube is coaxial to the tank duct.
4. Valve according to claim 1 , wherein the valve body comprises a neck and the tank duct is made through the neck.
5. Valve according to claim 4 , wherein a width of the blocking device is narrower than a width of the neck of the valve body.
6. Valve according to claim 4 , wherein the blocking device is positioned externally to the valve body, in a position axially alongside the neck.
7. Valve according to claim 1 , wherein the feed duct further comprises an auxiliary passage, connectable upstream with the by-pass duct and connectable downstream with the delivery duct, and wherein a closure seat is present between the by-pass duct and the auxiliary passage engageable by a manual tap, and wherein a valve seat is present between the auxiliary passage and the delivery duct engageable by a remote control electrovalve.
8. Valve according to claim 7 , wherein the auxiliary passage, the closure seat and the valve seat are made in the valve body.
9. Valve according to claim 7 , wherein the tap comprises an obturator body and a shaft manually rotatable around a knob axis, wherein the obturator body is engaged with a translation guide and the shaft is connected to the obturator body by a thread, so that the obturator body is only translatable along the knob axis by rotation of the shaft to engage or disengage the obturator seat.
10. Valve according to claim 1 , comprising a non-return device, operating between the entry duct and the tank duct and normally closed to obstruct an exit of methane through the entry duct and adapted to switch to an open configuration by action of the methane in supply.
11. Valve according to claim 1 , comprising an auxiliary tank duct.
12. Valve according to claim 1 , wherein the valve body is made in one piece.
13. Valve according to claim 12 , wherein the valve body is of bronze or aluminium.