US2649777A - Safety valve device for gas burners - Google Patents

Description

Aug. 25,- 1953 e. SAPER-SZTEJN 2,649,777

SAFETY VALVE DEVICE FOR GAS BURNERS AND THE LIKE Filed March 8, 1951 m- 18 I (ll/"M17 1 4 z I O ,f O m Eli 7 FL,

Patented Aug. 25,1953

SAFETY VALVE DEVICE FOR GAS BURNERS AND THE LIKE Gerson Saper-Sztejn, Grenoble, France Application March 8, 1951, Serial No. 214,550 In France March 11, 1950 6 Claims. 1

My invention relates to a safety valve used in connection with gas burners and the like in order to close the gas inlet to the burner when the auxiliary pilot burner is not in action.

A first object of my invention is to provide a safety valve device which will comprise no diaphragm, no stuffing box or the like liable to be easily damaged in operation and to cause gas leakage.

Another object of my invention is to provide a safety valve device wherein a valve member is controlled by a magnetic controlling member which is itself acted upon through a tight nonmagnetic partition, by another magnetic controlling member carried by a thermosensitive element. 7

It will be appreciated that with such an arrangement the thermosensitive element has no friction force to overcome. Anyv leakage is quite impossible and the device comprises no part liable to become accidentally inoperative in use.

In the annexed drawings:

Fig. 1 is a vertical section of a gas burner provided with a safety valve in accordance with my invention, wherein the thermos'ensitive element is a bimetallic strip.

Fig. 2 illustrates another construction wherein the thermosensitive element is a heat expansible fluid.

Fig. 3 shows a further construction wherein the thermosensitive element is a metallic tube.

Fig. 4 shows another embodiment of an apparatus comprising a bimetallic strip.

In the Fig. 1 the main burner comprises a plurality of elements such as I carried by an annular chest 2 to which gasis led through a tube 3. The latter is connected with the main gas line 4 through a valve formed of a ball 5 adapted to cooperate with the outlet of a bore 6 provided in a valve body I, the said bore communicating through a hole 8 with a chamber 9 of body 1. The gas line 4 opens itself in chamber 9.

Ball 5 is normally held above the outlet of bore 6 by a light spring I 0 housed within the said bore, but it may be pressed against this outlet by a cylindrical valve controlling member I I made of a suitable magnetic material and treated so as to form a permanent magnet. This member is slidably housed within a vertical cylindrical sleeve I2 made of an appropriate nonmagnetic material such as brass. Sleeve I2 is closed at its upper end while its lower end is closed by the valve body I, itself, tube 3 opening laterally into the said sleeve I2 in the vicinity of the lower end thereof.

Sleeve I2 is provided with a lateral boss I3 to which there is secured by a screw I4 one end of a U-shaped bi-metallic strip I5, the other end of which carries a second valve controlling member formed of a small block of soft iron I6 fixed at the end of the said strip I 5 by a screw II. Strip I5 is so arranged that in the cold state it is slightly open, as shown in dash lines, while when it is heated it assumes the exact shape of an inverted U, block I6 then being situated immediately above the upper end of sleeve I2 and at a very small distance therefrom, as illustrated in full lines.

The auxiliary or pilot burner I8 associated with the main burner is so disposed that it heats a portion of strip I5. In the example illustrated this pilot burner is arranged to produce a plurality of gas flames, one of which is directed towards the bend of strip I5, the said burner I8 being carried by a small vertical tube I9 fixed to a bracket 20.

When the .pilot burner I8 i not in operation, the bimetallic strip I5 is in the cold state and it therefore assumes the open U shape indicated in dash lines, whereby block I6 is laterally disposed with respect to sleeve I2. The magnetic action between block I6 and magnet II is very small, and therefore the said magnet rests on ball 5 which closes the outlet of bore 6 against the action of the light spring I 0. The main burner is thus kept inoperative and the gas is not permitted to escape by the elements .of this main burner. On the contrary when the pilot burner I8 is in operation, one of its flames heats the bimetallic strip I5 which assumes the true U shape indicated in full lines. Block I6 then acts on magnet II with a force suflicient to raise the said magnet, whereby ball 5 is free to move upwardly under the action of spring I 0. The gas from the main line 4 is thus permitted to flow towards the main burner where it is lighted in the usual manner by the pilot burner.

In the construction illustrated in Fig. 2 the soft iron block I6 is carried by an arm 2| pivoted at 22 and provided with a lateral lug 23 provided with teeth in meshing engagement with the threads of a member 24. Member 24 is pressed upwardly by a spring 25 which thus tends to lower the soft iron block I6 towards the closed end of the sleeve I2 enclosing the valve controlling magnet I I, such spring resting against an annular abutment 26 adjustable in position by means of a screw 21. Member 24 is internally threaded and it receives a screw 28 the head 29 of which bear against a manometric diaphragm 3 30. The latter forms the bottom of a small chamber 3! which extends upwardly in the form of a tube 32 closed at its upper end, the said tube being heated by the pilot burner 18.

Chamber 3| and tube 32 being filled with an appropriate fluid, the device is so adjusted that in the cold state block I6 is well above the closed end of sleeve !2 and is thus unable to raise masnet ll within the said sleeve [2. When tube 32 is heated the fluid in the said tube expands and causes diaphragm 30 to bulge downwardly whereby member 24 is lowered against the upper end of sleeve l2 and it attracts magnet H. Ball is raised and the gas is permitted to flow towards the main burner not illustrated.

The adjustment is effected by rotation of member 24 the threads of which displace vertically the lateral lug 23 of arm 2|, and also by screw 21 which acts on the initial tension of spring 25.

In the construction of Fig. 3 member 2d is directly attached at the lower end of a rod 33 made of steel substantially unafiected by heat expansion, the upper end of the said rod being in turn attached. to a tube 34, made of bronze or other highly expansible metal, within which rod 33 is slidable. The lower end of tube 34 is finally secured to the fixed casing 35 of the apparatus. The pilot burner I3 is so disposed as to heat tube 34. Spring 25 of Fig. 2 is here dispensed with.

Member 24 being secured to the lower end of rod 33 the upper end of which is secured to tube 34 which is fixed by its lower end to casing 35, it will be appreciated that when the unit Bit-34 is heated by the pilot burner it the displacements of member 24 with respect to casing 35 will be equal to the difference between the expansion of tube 34 and the expansion of rod 33 under the action of temperature. And since rod 33 remains almost unaffected while tube at is highly expansible, member 24 will raise when the pilot burner is normally operative.

Consequently the soft iron block it will be lowered against the upper end of sleeve l2 whereby magnet H is caused to rise, as explained in the case of Fig. 2.

Fig. 4 shows a construction which may be considered as a modification of the arrangement illustrated in Fig. 1. The valve enclosed within the valve body i is in the form of a disc 5a bearing on a fixed pin [35. The gas line 4 opens into sleeve I2 while tube 3 is connected to the lower chamber 9 of body I. The inner valve controlling magnet Ha is in the form of a conventional U- shaped member with the magnetic poles at the ends of the U, this member being guided'by a central projection 36 formed on the lower face of the upper end of sleeve [2. The U-shaped bimetallic strip l5a, secured at one end by two screws I la, is not in a wholly inverted position, as in the case of Fig. 1, but it is disposed horizontally. The operation of the apparatus remains quite the same.

It will be appreciated that in all the constructions described, the magnet could be formed by the outer block it, while the inner valve conseat 6a, the said disc being guided by a r' trolling member ll would be made of soft iron, or also both the inner valve controlling member and the outer block could be in the form of permanent magnets with the poles appropriately disposed to ensure mutual attraction.

I claim:

1. A thermostatically operated valve for gas burners and the like, comprising a tightly closed casing having an upper and lower wall, said casing being made of nonmagnetic material and adapted to be connected with a gas line, said casing having a gas outlet passage; a valve member adapted to close said gas outlet passage; a U- shaped permanent magnet disposed within said casing with its poles turned upwardly and vertically movable within said casing, said magnet resting on said valve member to maintain same in closed position by its own weight; an inner projection within said casing passing between the poles of said U-shaped permanent magnet to guide same; a thermosensitive element exterior to said casing and arranged to move its free end substantially vertically and downwardly above said casing when it is heated; a block of magnetic material at the movable end of said thermosensitive element to cooperate with said permanent magnet through the upper wall of said casing to cause said magnet to rise within said casing when said thermosensitive element is heated; means for heating the thermosensitive element; and means to raise said valve member when said permanent magnet is raised by heat applied to the thermosensitive element.

2. In a valve as set forth in claim 1, said raising means comprising a compression spring interposed between the valve member and the lower wall of the casing.

3. In a valve as set forth in claim 1, said raising means consisting of the valve member being formed of soft iron whereby same will rise and fall with the permanent magnet.

4. In a valve as set forth in claim 1, said inner projection being disposed on the underside of the upper wall of the casing.

5. In a valve as set forth in claim 1, said valve member having a rounded head forming a swivelling abutment for the permanent magnet.

6. .In a valve as set forth in claim 1, said raising means comprising a compression spring interposed between the valve member and the lower wall of the casing, and a fixed pin in the casing slidably engaging the valve member around which the said spring is mounted.

GERSON SAPER-SZ'I'EJN.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,199,975 Whitney May 7, 1940 2,227,901 'I-Iageman Jan. '7, 1941 2,299,155 Lange Oct. 20, 1942 2,353,740 Malone July 18, 1944 2,533,491 McMahon Dec. 12, 1950 2,575,086 Atchison Nov. 13, 1951

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