Patent Application
20160169399
The present invention relates to gas shut-off valves with thermal safety.
Gas valves are widely known and used. Gas valves serve to allow, prevent or regulate the passage of gas from one point (inlet) to another point (outlet). Valves that acquire two positions, i.e., open and closed positions, are commonly known as shut-off valves.
There are different types of shut-off valves. Some of them are shut-off valves that open or close depending on electric signals, for example. These include ON-OFF type shut-off valves where a coil is powered for opening the valve and it remains open as long as the coil is being powered, and flip-flop type shut-off valves where the valve is opened by providing a current pulse to the power supply but continuous power supply is not needed to keep the valve open, a current pulse opposite the first pulse being applied for closing said valve.
Valves using permanent magnets and elements with ferromagnetic properties for maintaining a state of the valve are known. As a result of the ferromagnetic properties of the element and the magnetic field of the permanent magnet, said element remains adhered to the permanent magnet, thus maintaining the state of the valve. When a specific temperature is exceeded, the element loses its ferromagnetic properties and no longer adheres to the permanent magnet. This temperature where the element loses its ferromagnetic properties is known as the Curie temperature.
Document GB 1485215 discloses a gas shut-off valve that is usually closed and opens when a specific temperature in its surrounding areas is exceeded. The valve comprises a permanent magnet and a heat sensing element having a Curie temperature equal to or greater than a gas ignition temperature, such that the heat sensing element loses its ferromagnetic properties when the temperature exceeds said value and is separated from the permanent magnet, the valve being opened. Therefore, the valve only opens once a specific temperature, which corresponds with the flame ignition temperature, has been exceeded and it can also be used as a flame detector.
The safety gas shut-off valve comprises a gas inlet, a gas outlet, an intermediate opening between the inlet and the outlet, and a shut-off element which blocks or closes the intermediate opening in a shut-off position, preventing the passage of gas from the inlet to the outlet, and allows said passage in an open position.
According to one implementation the valve further comprises a cover, a ferromagnetic element which is fixed to the shut-off element and comprises a specific Curie temperature, a spring associated with the shut-off element through a first end and with the cover through a second end, and a permanent magnet attached to the cover. As a result of the ferromagnetic properties of the ferromagnetic element and the magnetic field generated by the permanent magnet, said ferromagnetic element adheres to the permanent magnet, the intermediate opening being open, and the valve therefore being open. When a specific temperature which corresponds with the specific Curie temperature for the ferromagnetic element is reached, the ferromagnetic element loses its ferromagnetic properties and due to the action of the spring, said ferromagnetic element is separated from the permanent magnet and the shut-off element closes the intermediate opening, the valve being closed.
The valve allows uses other than those which are common in gas shut-off valves, such as the use thereof as a safety device to prevent something worse from happening in the event of fire or unwanted blazes, for example.
The configuration of the valve of the invention and the arrangement of its elements gives rise to obtaining a valve in an easy, simple and compact manner fulfilling the function of closing automatically in response to adverse conditions such as fire or unwanted flame in the proximities of the actual valve, for example; in summary, a valve that closes automatically when unwanted temperatures are reached in its surrounding areas is achieved.
Therefore, as a safety measure in response to fire, this valve can be arranged in the entrance of a house, of the kitchen or of the room where gas is used, such that if fire is detected, said valve will automatically cut off the gas supply to the house, kitchen or room and stop further feeding the fire. As a safety measure in response to an unwanted flame such as when oil in a frying pan catches fire, for example, this valve can be arranged above the burners where the frying pan is arranged (in a hood, for example, if there is one), such that in response to the presence of the unwanted blaze in the frying pan, the valve would close, cutting off the passage of gas to the burner that heats the flame. These examples are merely illustrative and in no case limiting, since the valve can also be used in ovens and cooktops, for example, and in the outlets of butane cylinders to prevent gas from seeping out of the cylinders when the temperature in the surrounding area of the valve exceeds a specific value.
These and other advantages and features will become evident in view of the drawings and the detailed description.
The body 11 further comprises a housing 12 which is arranged between the inlet conduit 13 and the intermediate opening 3 and on the intermediate opening 3. The housing 12 serves for housing the elements of the valve 100 which work together for opening or closing the valve 100 and which will be explained below. To facilitate the assembly of the valve 100, particularly to facilitate the insertion of said elements in the housing 12, said housing 12 is accessible from outside the body 11. For the operation of the valve 100, the housing 12 stops being accessible from the outside, and to that end the valve 100 comprises a cover 5 and at least one sealing element 17 between the cover 5 and the body 11 to prevent gas inside the valve 100 from leaking out through the areas of attachment between the cover 5 and the body 11.
The valve 100 comprises a shut-off element 4 which has a specific profile suitable for being able to block or close the intermediate opening 3 when required, housed in the housing 12 and suitable for closing the intermediate opening 3 in a shut-off position and preventing communication between the inlet 1 and the outlet 2, and therefore preventing gas from being able to reach the outlet 2 from the inlet 1, not preventing said communication in an open position. In the embodiment shown in the drawings, the shut-off element 4 is suitable for moving transversely with respect to the longitudinal axis 11a of the body 11 for changing position. The shut-off element 4 has a specific profile which is suitable for closing the intermediate opening 3 when required.
The valve 100 comprises a ferromagnetic element 6 which is arranged in the housing 12 fixed to the shut-off element 4, moving integrally with it and comprising a specific Curie temperature that depends on what is required, as will be explained below. The valve 100 further comprises in the housing 12 a spring 7 associated with the shut-off element 4 through a first end and with the cover 5 through a second end, and a static permanent magnet 8. In one embodiment, the permanent magnet 8 is attached to the cover 5, and to facilitate this attachment the cover 5 is made of a ferromagnetic material such that the cover 5 and the permanent magnet 8 are attached to one another as a result of the permanent magnetic field generated by the permanent magnet 8. In other embodiments, it is also possible to use other types of attachments to attach the cover 5 and the permanent magnet 8 to one another. The ferromagnetic element 6 is arranged between the shut-off element 4 and the permanent magnet 8.
According to one implementation the shut-off element 4 is an element of revolution comprising two concentric sections arranged one after another. A first section comprises a smaller radius but a greater length than a second section. The first section is covered by the ferromagnetic element 6, and the second end of the spring 7 is associated with the second section of the shut-off element 4. In the embodiment shown in the drawings, the spring 7 is supported on the second section of the shut-off element 4 but it may be attached to said second section.
In the embodiment shown in the drawings, the sealing element 17 and the shut-off element 4 are part of one and the same element that corresponds with a membrane 40. Therefore, the functions of sealing (a function of the sealing element 17) and closing the valve 100 (a function of the shut-off element 4) are performed with a single element (membrane 40), which facilitates the manufacture and assembly of the valve 100. The membrane 40 is arranged in the housing 12 of the body 11 of the valve 100 and is manufactured from an elastomer material, the part of the membrane 40 connecting the sealing element 17 and the shut-off element 4 being flexible. A space where the ferromagnetic element 6, the spring 7 and the permanent magnet 8 are arranged is defined between the cover 5 and the membrane 40. In other embodiments relating to the embodiment shown in the drawings, the sealing element 17 and the shut-off element 4 can be two independent elements.
The operation of the valve 100 is explained below.
When the valve 100 is open, the permanent magnetic field generated by the permanent magnet 8 causes the ferromagnetic element 6 to adhere to the permanent magnet 8, as shown in
The spring 7 is sized and configured such that when the valve 100 is open the spring 7 is compressed. When the surrounding area of the valve 100 exceeds the predetermined Curie temperature of the ferromagnetic element 6, the ferromagnetic element 6 loses its ferromagnetic properties and is no longer attracted by the permanent magnet 8. In this situation, the force of the compressed spring 7 does not withstand any counteracting force and the spring 7 expands to recover its standby shape, causing the shut-off element 4 which is associated with the second end of the spring 7 to move towards the intermediate opening 3, closing it. The ferromagnetic element 6 moves integrally with the shut-off element 4, being separated from the permanent magnet 8. In this situation, the valve 100 is closed and the spring 7 is in standby, as shown in
In the embodiment shown in the drawings, the valve 100 comprises a manual actuator 9 for manually opening same. The valve 100 can thus be opened manually, such action being depicted in
The body 11 comprises a through hole 111 communicating the inside of the valve 100 with the outside of the valve 100, and the manual actuator 9 comprises a rod 90 passing through the through hole 111. The valve 100 comprises a sealing element 16 to prevent gas inside the valve 100 from leaking out due to the through hole 111, and to that end the body 11 comprises a housing 112 where the sealing element 16, which corresponds to an O-ring, is arranged. In the embodiment shown in the drawings, the housing 112 is arranged outside the valve 100, although in other embodiments relating to this embodiment, the housing can be arranged inside the valve 100.
The rod 90 comprises a first zone inside the body 11, particularly in the outlet conduit 32, and a second zone outside the body 11. A first end of the rod 90, belonging to the first zone, is facing the shut-off element 4, and a second end of the rod 90, belonging to the second zone, is accessible for a user. The valve 100 comprises a spring element 15 which is arranged outside the body 11 and associated with the second end of the rod 90. Said second end comprises a seat 91, and the spring element 15 is attached to said seat 91 through a first end and associated with the body 11 through a second end opposite said first end. In the embodiment shown in the drawings, the spring element 15 is supported on the seat 91 of the rod 90 but it may be attached to said seat 91. The second zone of the rod 90 goes through the spring element 15.
When a user acts on the manual actuator 9 for opening the valve 100, the rod 90 is moved towards the shut-off element 4, pushing it. The rod 90 is aligned with the shut-off element 4 and is moved in alignment with said shut-off element 4, transverse to the longitudinal axis 11a of the body 11. In the embodiment shown in the drawings, the shut-off element 4 comprises a housing 41 to facilitate the actuation of the rod 90 thereon, although it may not have said housing 41. As the shut-off element 4 pushed by the rod 90 moves, the ferromagnetic element 6 also moves and adheres to the permanent magnet 8, the valve 100 remaining open even when the shut-off element 4 is no longer being pushed (provided that the temperature in the surrounding area of the valve 100 is less than the predetermined Curie temperature). When the user stops acting on the manual actuator 9, the spring recovers its standby position, forcing the rod 90 to return to its initial position. Therefore, when the temperature in the surrounding area of the valve 100 reaches the Curie temperature, the valve 100 can be closed because if the rod 90 does not return to its position, said rod would prevent the movement of the shut-off element 4 for closing the intermediate opening 3.
In other embodiments that are not depicted in the drawings, the valve 100 is similar to that of the drawings but it neither comprises nor is it associated with the manual actuator 9 (spring element 15, through hole 111, housing 112, O-ring 16).
| Number | Date | Country | Kind |
|---|---|---|---|
| U 201330662 | May 2013 | ES | national |
This application relates to and claims the benefit and priority to International Application No. PCT/EP2014/060498, filed May 22, 2014, which claims the benefit and priority to Spanish Application No. U 201330662, filed May 29, 2013.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2014/060498 | 5/22/2014 | WO | 00 |
