US2815768A - Control means for gaseous fuel burners - Google Patents

Description

I Dec. 10, 1957 R. 'r. HUYCK 2,815,768

CONTROL MEANS FOR GASEOUS FUEL BURNERS Filed Jan. 9, 1956 7 IN VENTOR.

United States Patent H 2,815,768 Patented Dec. 10, 1957 ice CONTRUL MEANS FOR GASEOUS FUEL BURNERS Robert T. Huyck, Kenmore, N. Y., assignor to Roberts- Gordon Appliance Corporation, Bufialo, N. Y.

Application January 9, 1956, Serial No. 558,010

6 Claims. (Cl. 137-628) This invention relates to means for operating the valves which control the admission of. gaseous fuel and air to a burner.

In control devices of this kind as heretoforeconstructed using electrically operated diaphragm gas valves, a lever arm was actuated by the valve and arranged to control an 'air louver so that air would be admitted to the burner slightly before the gas valve was turned on. It was also possible with such designs to actuate the lever manually without effecting the opening of the gas valve. This feature, however, in prior controls permitted the burner to be operated under hazardous conditions in the event that the control means were improperly adjusted so that the valve would open without opening the air louver. The control means might, when thus adjusted, admit gas to the burner before air is admitted to the same, thus producing a hazardous condition.

It is, consequently, an object of this invention to provide a mechanism which will facilitate the correct installation of control means of this type and make it practically impossible for an installation mechanic to make an incorrect and hazardous installation. It is also an object of this invention to provide mechanism including a latching device which will engage a stop when the louver operating lever is operated manually but which latch will not engage the stop when the lever is operated automati cally by the valve diaphragm.

Other objects and advantages will be apparent from the following description of one embodiment of the invention and the novel features will be particularly pointed out hereinafter in connection with the appended claims.

In the accompanying drawings:

Fig. l is a central sectional elevation of a diaphragm controlled valve and louver provided with latch and stop means embodying this invention.

Fig. 2 is a fragmentary sectional view thereof, showing the parts in different positions.

-In these drawings, which illustrate by way of example, one embodiment of my invention, I have shown a control means of well known construction including a gas valve having a housing 5 provided with the usual valve member 6 for interlupting or permitting the passage of gaseous fuel to a burner (not shown) and 7 indicates an air duct having a louver 8 mounted to swing about a pivot 9 to admit air through the air duct 7 to the burner.

The gas valve 6 is mounted on the lower end of a valve stem It which is slidable in a suitable cap 11 secured to the valve housing 5. A guide sleeve 12 extends through the cap and is provided in its bore with slots or passages 14 through which gas may pass from the interior of the valve housing 5. A weight 15 is preferably mounted on the stem to urge the valve 6 into closing position on its seat, and 17 represents a sleeve also secured to the valve stem, which is: preferably threaded to cooperate with screw threads in thesle'eve and. the weight 15. The sleeve is. preferably: provided. with. a collar at the upper end thereof and a locknnt atathe lower end, so that the sleeve may be adjusted lengthwise of the valve stem and locked in place thereon.

The valve 6, in the particular construction shown, is opened and closed by suitable actuating means, such for example as a diaphragm 20 arranged in a diaphragm housing or casing 21 and the diaphragm is suitably connected with the valve stem, for example, by means of a stirrup or strap 22 of approximately inverted U-shape, the middle portion of which is'suitably connected with the diaphragm 20 and the lower ends of the legs of which are connected with a disk 25 or platform having an aperture through which the sleeve 17 extends. When the diaphragm is moved upwardly from the position shown in Fig. l, the disk or platform 25 engages the upper shoulder of the sleeve 17 and thus raises the valve 6 from its seat. When the diaphragm is'lowered, the valve is moved to its seat by gravity and by the pressure of the gas acting on the upper surface of the valve, and weight 15 also serves to seat'the valve.

Gas from the left-hand side of the valve housing 5 as shown in Fig. 1 passes upwardly through the passages 14 in the sleeve 12 and underneath the weight 15 and then upwardly in a tubular connection 27 between the valve cap 11 and the lower part of thediaphragm housing or casing 21, and consequently, enters the lower part of this casing and exerts an upward pressure on the diaphragm which, however, is counteracted by gas pressure acting on the upper face of the diaphragm 20. For this purpose, a passage 28 is provided which connects with the casing 21 below the diaphragm and another pas sage 29 which connects with the casing'above the diaphragm. When the gas is discharged from the part of the casing above the diaphragm, then the pressure of gas acting on the lower face of the diaphragm will move the same upwardly and open the valve.

The movement of the diaphragm for opening and closing the valve may be effected by suitable electric mechanism of usual and well-known construction and which is not herein shown or described in detail, which acts on a valve 36 arranged in a chamber 31 in which the passages 28 and 29 terminate. This valve normally seats on the upper end of a bleeder or discharge passage 32. When this valve 30 is in its lowest position as shown in Fig. 1, it closes the discharge passage 32 and permits gas from the lower part of the diaphragm housing to enter into the upper part thereof, thus keeping thelgas valve 6 in closed position. When the electric mechanism moves the valve member 30 upwardly, it closes the passage 28 leading into the chamber 31, thus preventing flow of gas through the passage 28 and permitting gas above the diaphragm to be discharged into the bleeder passage 32 from which it passes into a pipe 34 leading to the combustion chamber of the furnace or other heating device. All of these parts have heretofore been used in connection with electrically controlled diaphragm valves .and may, if desired, be replaced by other constructions.

The diaphragm 2t in addition to moving the gas valve 6 into and out of closing position also actuates a lever 37, one end of which is suitably connected with the air louver 8, for example, by means of a chain 38. When the outer end of the lever is lowered, it will be obvious that the louver 8 will swing by gravity about its pivot 9 to admit air into the air duct 7. This lever is secured on a shaft 40 which extends into the interior of an extension 41 of the diaphragm housing 21 and is pivoted thereon. The other arm of the lever is formed by a weighted part 42 arranged within the diaphragm housing and secured to the shaft 40; This lever arm 42 is of bifurcated form, the two legs thereof straddling the stirrup or strap 22. To lever arm 42' is formed to rest on the disk or platform. 25 and for this purpose, is provided on the two legs thereof withdownwardly extending prcjections 44 which rest on the disk or platform 25. Consequently, the weight of the arm 42 holds the lever in a position in which the outer end thereof is raised, so as to close the air louver 8. When the valve is moved into open position by the diaphragm, the platform or disk 25 raises the arm 42, thus lowering the outer end of the lever and opening the air louver 8. Preferably a slight clearance is initially provided between the disk or platform 25 and the upper flange of the sleeve 17, so that the air louver will be opened slightly before the gas valve is opened.

In order to ensure against the opening of the gas valve without a corresponding opening of the air louver, I provide a locking latch or abutment engaging element 47 which in the construction shown is pivoted on one leg of the bifurcated arm 42 of the lever. This latch has a lower edge portion which rests flatly upon the disk or platform 25 during the normal operation of the control device. A pivot 48 connects the latch with the arm 42 and is arranged at one side of the latch so that the latch when supported only by the pivot is in an unbalanced condition and tends to swing in a clockwise direction when lifted from the supporting platform or disk 25. Consequently, when the outer end of the lever 37 is swung downwardly manually, the inner arm 42 thereof is swung upwardly and without movement of the diaphragm 20, the latch will be lifted upwardly relatively to the disk or platform 25. Because of its unbalanced con dition with reference to the pivot 48, the latch will then swing in a clockwise direction and a pointed end or projection a of the latch will swing to the right. A locking or abutment member 51 is mounted within the diaphragm casing and is provided with a hook-shaped projection 52 which is located in position to be engaged by the pointed end or projection 50 of the latch when the same is swung upwardly relatively to the platform or disk so that the parts will then be in the position shown in Fig. 2. When in this position, farther downward movement of the outer end of the lever 37 is prevented.

This construction is particularly desirable in aiding persons installing the valve control mechanism. In most burner installations, the air ducts are differently positioned with relation to the gas valves, and consequently, it is necessary for the mechanic who installs the control device to adjust the relationship between the lever 37 and the air louver 8, and this adjustment may be dififerent for each different installation. Since the mechanic installing the control device cannot, of course, see the position of lever arm 42, it is possible that he may make the connection 33 between the lever and the air louver too short, in which case, without the mechanism of this invention, the gas valve may open in advance of the louver 8. Such condition might also arise after correct adjustment, should the relative position between the valve and the air louver be changed, as may occur should the fuel line be strained by subsequent piping Work, or by accidental impact against either the valve or air duct assembly.

Opening of the gas valve in advance of the louver is hazardous in that there will be admitted to the combustion chamber a quantity of gas without sufiicient air to permit normal ignition by the pilot flame, and this accumulation of gas can ignite explosively after the louver opens and permits air to flow into the combustion chamber. Under the extreme condition of misadjustment whereby the linkage between the valve lever and the louver is so adjusted that the louver cannot open even when the valve is fully open, an equally hazardous condition exists, in which the entire combustion chamber and furnace vent will contain unburned gas, which can be ignited explosively upon admission of air into the accumulated gas. The latch 47, therefore, acts as a safeguard to prevent incorrect installation of the control device, since by correct positioning of parts of the valve 6,

the diaphragm and their connections at the factory, the mechanic installing the control device on a furnace cannot lower the outer end of the lever 37 to such an extent that the gas valve 6 can open previous to admission of air through louver 8. Consequently, he can readily determine the required length of the connection 38 between the air louver and the outer end of the lever 37, to enable the air louver to be opened slightly in advance of the gas valve. In the event that he fails to make the correct adjustment, leaving latch 47 engaged with stop 52, it becomes impossible to open the valve either manually or automatically.

It will be understood that various changes in the details, materials, and arrangements of parts which have been herein described and illustrated in order to explain the nature of the invention, may be made by those skilled in the art within the principle and scope of the invention, as expressed in the appended claims.

I claim as my invention:

1. Movement controlling means for preventing opening of a gas valve Without corresponding opening of an air louver, said means including a lever connected at one end thereof with said louver for controlling opening and closing of the same, actuating means for opening and closing said valve, a connection between said actuating means and said valve which opens said valve and swings said lever into louver opening position, said lever being free to move to a limited extent into louver opening position without opening said gas valve and being movable into louver opening position independently of said actuating means, and stop means for limiting movement of said lever relatively to said valve and said actuating means, said stop means being inoperative when said lever is actuated by said actuating means.

2. Movement controlling means for preventing opening of a gas valve without corresponding opening of an air louver, said means including a lever connected at one end thereof with said louver for controlling opening and closing of the same, actuating means for opening and closing said valve, a connection between said actuating means and said valve which opens said valve and swings said lever into louver opening position, said lever being free to move to a limited extent into louver opening position without opening said gas valve and being movable into louver opening position independently of said actuating means, an abutment engaging element pivotally mounted on said lever, and an abutment member with which said abutment engaging element engages when said lever is moved into louver opening position without movement of said valve into opening position.

3. Movement controlling means for preventing opening of a gas valve without corresponding opening of an air louver, said means including a lever connected at one end thereof with said louver for controlling opening and closing of the same, actuating means for opening and closing said valve, a connection between said actuating means and said valve and which includes a platform connected with said valve, the other end of said lever normally resting on said platform, said connection and platform when raised by said actuating means opening said valve and swinging said lever to open said louver, said lever being movable into a position to open said louver independently of said actuating means and connection by lifting the other end thereof from said platform without opening said valve, an abutment engaging latch pivoted on said other end of said lever and also resting on said platform, and an abutment member with which said latch engages when said lever is swung into louver opening position which swings said latch above said platform, said latch when moved upwardly with said platform being maintained by said platform in position to clear said abutment member.

4. Movement controlling means for preventing opening of a gas valve without corresponding opening of an air louver, said means including a lever having one arm connected with said louver, a diaphragm for raising and lowering said valve, a platform connected with said diaphragm and movable therewith to raise said valve into open position, said lever having another arm resting on said platform, said platform, when raised by said diaphragm, swinging said lever through said arm to open said louver, said lever being free to swing into louver opening position independently of said diaphragm and valve by lifting said other arm from said platform, an abutment engaging element connected with said lever and resting on said platform when said lever is in position to close said louver, a pivot arranged eccentrically with reference to said abutment engaging element, and connecting said abutment engaging element with said lever, said lever when swung by external force raising said abutment engaging element from said platform to permit said abutment engaging element to swing about its pivot, and an abutment member mounted in fixed relation to said valve for engagement by said abutment engaging element when the same is swung upwardly from said platform by said lever and being out of the path of movement of said abutment engaging element when raised by said platform, said abutment member being so positioned relatively to said abutment engaging element that said abutment engaging element engages said abutment member before said lever reaches a position in which said valve is moved into open position.

5. Movement controlling means for preventing opening of a gas valve without corresponding opening of an air louver, said means including a lever having one arm connected with said louver, a diaphragm connected with said valve for raising and lowering the same into and out of open position, a platform connected with said diaphragm and movable therewith to raise said valve,

said lever having its other arm normally resting by gravity on said platform, said platform, when raised by said diaphragm, swinging saidlever to open said louver, said lever being free to swing into louver opening position independently of said diaphragm and valve by lifting said other arm from said platform, an abutment engaging element connected with said lever, an abutment member mounted in fixed relation to said gas valve for engagement by said abutment engaging element when the same is moved by said lever independently of said platform, said platform holding said abutment engaging element out of operative relation to said abutment member when said lever is swung by said platform.

6. Movement controlling means for preventing opening of a gas valve without corresponding opening of an air louver, said means including a lever connected with said louver and said valve for controlling the opening and closing of said louver, controlled means for opening and closing said valve and moving said lever into louver opening position, a part connected with said controlled means and with said valve on which one end of said lever rests by gravity when said louver is in closed position, said lever being free to swing into louver opening position independently of said controlled means and valve by lifting said one end from said platform, an abutment member arranged in fixed relation to said valve, and an abutment engaging element held in inoperative relation to said abutment member when-said one end of said lever rests on said part and which is moved into a position to engage said abutment member when said end of said lever is moved away from said part.

No references cited.

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