US2815769A - Control means for gaseous fuel burners - Google Patents

Description

Dec. 10, 1957 R. T. HUYCK 2,815,769

. CONTROL MEANS FOR GASEOUS FUEL. BURNERS Filed Dec. 6, 956

5 5 40 I: 4 m J 77 2 4 7 Q0 W INVENTOR. Y i 5% United tates Patent CONTROL IWEAN S FOR GASEOUS FUEL BURNERS Robert T. Huyck, Kenmore, N. Y., assignor to Roberts- Gordon Appliance Corporation, Buffalo, N. Y.

Application December 6, 1956, Serial No. 626,743

3 Claims. (Cl. 137-6371) 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 heretofore constructed 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 producinga hazardous condition.

It is, consequently, an object of this invention to provide mechanism to facilitate the correct installation of electrically actuated control means of this type and make it practically impossible for an installation mechanic to make an incorrect and hazardous installation. A further object is to provide mechanism of this kind which will stall the motor so that it cannot open the gasvalve unless the air vent is first opened. It is also an object of this invention to prevent the gas valve from opening in advance of the air valve in the event that the parts of the mechanism become shifted out of their correct positrons.

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

In the accompanying drawings:

Fig. 1 is a central sectional elevation of an automatic motor operated fuel valve and showing diagrammatically its connection with an air admission vent, the valve being provided with a safety device embodying this invention.

Fig. 2 is a fragmentary central sectional elevation showing the parts in the positions in which the valve is locked in closed position.

In these drawings, which illustrate by way of example, one embodiment of myinvention, I have shown a control means of well known construction including a gas valve having a housing 5 provided with the usual valve memher 6 for interrupting 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 10 which is slidable in a suitable cap 11 secured to the valve housing 5. The valve stem 10 extends upwardly through suitable packing in the cap 11 into a control housing 14 and the upper end of the valve stem is pivotally connected at 15 to a valve actuating lever 16 pivoted at 17 on a fixed part of the control 2,815,769 Patented Dec. 10, 1957 2. housing 14. This housing may be of any suitable or desired construction and is preferably supported on the upper end of the valve cap 11. The lever 16 extends out of the control housing 14, one end extending through a slot 19 formed in this housing and the other end being provided with an extension projecting through a slot 20 in the opposite side of the housing.

The actuation of the lever 16 is effected by swinging this lever about its pivot 17, and this may be effected by any suitable motor or power device. In the particular control means illustrated, a motor (not shown) is arranged within the housing 14 and rotates a wheel or disk 21 having a pin 22 extending beyond a face thereof. This pin is arranged to engage a hook-shaped end of a link 24 which is pivoted at 25 on the lever 16. Consequently, when the disk 21 rotates in a clockwise direction in Fig. 1, the pin 22 will engage the hooked end of the link 24 and thus carry the link upwardly, and because of the connection between the link and lever 16, the lever will be swung in a clockwise direction about its pivot 17. This movement of the lever will cause the valve stem 10 to be moved upwardly, thus lifting the valve 6 from its seat and permitting gas to'flow to the burner. The motor employed in connectionvwith this valve control device is of the type which may be stalled without damage thereto and will, consequently, hold the valve in open position until a thermostatic control or other regulating device causes the current to the motor to be interrupted and when this occurs, the disk 21 is free to rotate in the reverse direction, thus permitting the lever 16 to move into the position shown in Fig. 1 in which the valve 6 is closed. 7

The lever 16 is provided with an outwardly extending arm 28 pivotally connected therewith. The outer end of this arm is connected with the air damper or louver 8 in any suitable manner, for example, by means of a wire link- 30, one end of which is pivotally connected with the damper 8 at a distance from the pivot 9, andthe other end-of which extends through a hole 31 formed in the end of the arm 28. The length of this link may readily be varied by varying the point at which theupper end thereof is bent to pass through the hole 31. The arm 28 is pivoted at 32 on the end of the lever 16, and the arm has an extension 33 which engages the pivotpin 17 about which the lever 16 swings. The arm 28 can, consequently, be swung down about its pivot 32 without opening the fuel valve 6. 35 represents a tension spring connected at its lower end with the arm 28 at a distance from the pivot 32. The upper end of this spring may be supported on a pin or rod 36 secured to the housing 14. This spring yieldingly holds the arm 28 and the lever 16 in the position shown in Fig. 1, in which the extension 33 of the arm engages the pivot member 17. The spring also serves the purpose of urging the lever 16 into valve-closing position against the action of the link 24, and returns the lever into valve closing position when the supply of current to the motor is interrupted.

From the foregoing description, it will be; seen that when the parts are correctly adjusted, the air louver 8 and the gas valve 6 will be opened in that sequence so that a proper mixture for combustion will be fed to the burner. However, it is somewhat dilficult to correctly install a control mechanism of this kind in such a manner as to be certain that the gas valve 6 will not be opened prior to the opening of the air louver 8, since this would introduce gas into the burner without an adequate supply of air to support combustion. If the air louver is then later opened, the admission of air will cause improper operation of the burner and possibly a hazardous condition. The proper adjustment of the parts of the control device is made ditficult by the fact that the mechanic making the installation cannot see the position of the gas valve 6 when adjusting the connection between the air damper 8 and the arm 28, and also he cannot see whether the extension 33 of the arm 28 engages the pivot member 17 or is spaced therefrom. He may, consequently make the link 28 too short, in which case both air damper and gas valve will be closed when the control motor is in shut-off position. However, when the motor operates to open the valve and damper, the fuel valve will be opened before the air damper, since this valve will be free to move upwardly alone until the extension 33 contacts with the pivot member 17, after which the air damper will begin to open. Hence with this incorrect adjustment, gas will flow into the burner and into the combustion chamber before air is admitted thereto, with the resulting possibility of damage to the furnace and injury to persons near the same.

In order to prevent the opening of the gas valve without a corresponding opening of the air vent, I have provided a locking bar 40 which may be made of a wire rod or other suitable material and which has one end thereof pivotally connected with the arm 28. For example, this bar may have one end thereof bent over and extending into an opening 41 formed in a downwardly extending part 42 of the arm 28. This pivotal connection of the locking bar 40 with the arm 28 is arranged well below the pivotal connection 32 of the arm 28 with the lever 16.

The locking bar 40 extends at its other end through a perforation in a guide projection 43 secured on the lever 16, so that this end of the locking bar may readily slide relatively to the guide projection 43, but is held against lateral movement relatively to this lever.

The housing 14 is also provided with a stop member 45 secured thereto and which is out of the path of movement of the lever 16 when swinging about its pivot. How ever, this stop member is so located adjacent to the end 46 of the stop bar that when the stop bar is moved to the left in Fig. 1, it will be in position to engage the under surface of the stop member 45 (Fig. 2), thus stopping upward movement of this end of the lever 16 and preventing lifting and opening of the gas valve 6. Consequently, if the control device is so installed that the connecting link 30 is too short, the arm 28 will be swung downwardly about its pivot 32 during this installation while the gas valve 6 is closed. The arm 28 may thus be moved, for example, approximately into the position shown in Fig. 2, which causes the stop bar 40 to move to the left so that the end 46 thereof will extend beneath the lower edge of the stop member 45. Consequently, if the motor turns the disk 21 for the purpose of opening the gas valve 6, the link 24 will not be able to swing the lever 16, so that the motor operating the disk 21 becomes stalled and the gas valve remains closed. The mechanic can then adjust the length of the link 30 so as to cause the gas valve 6 and air louver 8 to open in proper timed relation to each other.

It is also possible that the parts of the mechanism after correct installation may be moved out of correct relation to each other, for example, by a dislocation of the gas pipe with which the valve housing 5 is connected, relatively to the air vent 7, or the gas valve and air louver may be displaced relatively to each other by an impact or blow. When this occurs, it is possible that without my improvements, the gas valve may open before the air damper 8 is opened. However, with my improved construction, whenever the gas valve could otherwise open before the air damper, the arm 28 would swing relatively to the lever 16, and this would cause the lock bar 40 to be shifted so as to lock the lever 16 in the position shown in Fig. 2, and thus prevent opening of the gas valve.

It will be understand 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 the opening of a gas valve without corresponding opening of an air louver, including a lever connected with said valve for controlling the opening and closing of the same, an arm pivotally mounted on said lever and connected with said louver and biased to move with said lever, and automatic means for swinging said lever for opening and closing said valve and said louver, a locking bar slidably mounted on said lever and having one end thereof connected with said arm, and a stop with which said locking bar engages when said arm is swung relatively to said lever, to stop movement of said lever when said arm is swung relatively to said lever.

2. Movement controlling means for preventing the opening of a gas valve without corresponding opening of an air louver, including a lever connected with said valve for controlling the opening and closing of the same, an arm pivotally mounted on one end of said lever and connected with said louver, stop means on said arm and lever for limiting the swinging of said arm relatively to said lever in one direction, and spring means for holding said stop means in engagement, a locking bar mounted on said lever and having one end thereof connected with said arm, a fixed stop in operative relation to said locking bar, said locking bar being movable relatively to said lever into position to engage said stop when said arm is swung relatively to said lever against the action of said spring, to stop movement of said lever.

3. Movement controlling means for preventing the opening of a gas valve without corresponding opening of an air louver, including a lever connected with said valve for controlling the opening and closing of the same, an arm pivotally mounted on said lever and extending outwardly from said lever and having its outer end connected with said louver, said arm having a part extending at an angle to the length thereof, stop means on said arm for limiting the swinging of said arm relatively to said lever, spring means urging said arm into position to engage said stop means, a locking bar slidably mounted on said lever and having one end thereof pivotally connected with said extending part of said arm, and a fixed stop in operative relation to the other end of said stop bar and engaged by said stop bar when said arm swings relatively to said lever, to stop swinging of said lever.

No references cited.

Images