US2522063A - Cover operated switch - Google Patents

Description

P 2, 1950 P. M. SANTULLO 2,522,053

COVER OPERATED swrrcu Filed June 16, 1947 2 Sheets-Sheet 1 MM 6W Sept. 12, 1950 P. M. SANTULLO 3 COVER OPERATED swrrcu Filed June 16, 1947 2 Sheets-Sheet 2 /& I 3

Patented Sept. 12, 1950 UNITED STAT ES PATENT OFFICE f oovEn OPERATED swrrcn Pompeo M. Santullo, Newark, N. J.- 1 Application June 1-6, 1947, Serial No. 754,901"

' This invention relates. to an electrical cutout and alarm device for furnaces and the like, which burn a gaseous fuel or a fuel from which a, combustible gas is likely to accumulate in the flues thereof.

'In furnaces as gas burning furnaces, there exists the likelihood that unburned gas may accumulate in the lines due to the failure of the pilot or other igniter, and such'accumulated gas 'may later become ignited causing an explosion in the furnace and fluesj After the initial burning of such gases the fire may remain in the flues due to the gas being forced through the combustion chamber into the-flues by the forced draught blower. This burning of the gases in the fines results in damage to the flues and furnace and any v adjacent material.

It is an object of this invention to provide an "automatic switch for disconnecting the blower motor and sounding an alarm when gases are ignited in the fines. Flues of this type of furnace are frequently provided with a blow-out pipe and cover to permit the escape of such ignited gases and it is an object of this invention to utilize the blow-out pipe cover as an operator for a switch to disconnect the blower motor and connectan electric alarm circuit. 2

Another object of this invention is to provide a device of the kind to be more particularly attached to the blow-out covers of furnaces presently installed, with little or no modifications necessary to the furnaceor fiues. While provided primarily as an attachment, the device may as readily be built into the furnace and flue constructions presently in progress.

A further object of this invention is to provide a switch connected selectively with either the blower motor or alarm. In normal operationthe switch will complete the blower motor circuit and after a blow-out will complete the alarm circuit while breaking the motor circuit. While the device is so constructed to automatically move the switch in one direction, it may be manually reset after such automatic operation.

With the above and other objects in view, my invention consists in the arrangement, combination and details of construction disclosed in the drawings and specification, and then more particularly pointed out in the appended claim.

In the drawings,

Figure 1 is a side elevation of the electrical cutout and alarm device as attached to the blowout pipe of a furnace.

Figure 2 is a top plan view of the switch and switch operator,

1 Claim. (o1; 200-44) Figure 3 is a longitudinal section taken on the line 3-3 of Figure 2,

Figure 4 is a. transverse section taken on the line 4-4 of Figure 3,

Figure 5 is a fragmentary side elevation, partly in section, of the switch removed from the device, Figure 6 is a diagrammatic Wiring diagram.

Referring to the drawings, the numeral l9 designates generally a; furnace for burninggas, having a blower H driven by an electric motor I 2, and having flues [4. connected to the upper end of the combustion chamber, to a chimney [5. The flue [4 includes a. vertical tube It, and a horizontal tube H. The horizontal tube It is connected to the vertical tube 16 intermediate its length and communicates at one end with the chimney l5, and is open at the other end.

The open end of the horizontal tube. II is closed with a movable cover E8. The horizontal flue H is known as the blow-out pipe of the furnace.

In the use of gas furnaces when the pilot lights have become extinguished, combustible gases frequently accumulate in the fines above the combustion chamber. These combustible gases in the fines may become ignited through the subsequent lighting of the pilot light, or a spark or ther applied heat to the fiues. Such ignition of these combustible gases results in an explosion in the flues so the cover I8 is made removable to provide an exhaust for the exploding gases, to prevent damage to the fiues and to the furnace.

While the gases may accumulate in the fines due to their own weight, the blowers of the furnace move the gases more quickly into the fines. It is an object of this invention to provide a means for turning off the blower motor l2 and sounding an alarm when the explosion of gases in the fiues occurs. The alarm and cut-off device 20, constructed according to an embodiment of this invention, comprises a switch 2| in a housing 22 fixed on the blow-out pipe [1.

The switch 2| is operated in one direction by movement of the blow-out cover 18 for shutting off the motor I2 of the blower and for completing the circuit to an alarm 24, The housing 22 is rectangular in shape and open at the top, as indicated by the numeral 25. The housing 22 is fixed to the free end of the blow-out pipe l1. One leaf of a hinge 26 is fixed to the outer end of the housing 22 by a rivet 2'! or other suitable fastening devices. The other leaf 28 of the hinge 26 is fixed to the cover I8. The hinge leaves are connected together by a pintle 29 engaging through the barrels thereof.

An upwardly extending lever 30 is fixed to the blow-out cover l8 and extends upwardly into the housing 22. The double throw switch 2| is fixed to brackets 3| which are in turn fixed to the lower wall 32 of the housing 22. The switch 2| is formed with an operating handle 33. The handle 33 is biased in both directions for completing a circuit through the pairs of contacts at each end of the switch 2|, The handle 33 is formed with an opening 34 near the upper end.

A rod 35 is pivotally connected to the upper end of the lever 39 by a pivot pin 35, and loosely engages through the opening 34 of the handle 33. The end of the rod 35 which engages through the handle 33 is reduced in size to provide a shoulder 3! intermediate the length of the rod 35.

A spring 38 is coiled about the reduced end of the rod 35 and is compressible between the handle 33 and the shoulder 31; Such a connection Drovides a lost motion connection between the cover I8 and the handle 33 for moving the handle in one direction upon movement of the cover, and

the spring 38 constantly urges the cover Is to its normally closed position.

For resetting the switch 2|, a reset rod 39 is pivotally carried by the handle 33. The reset rod 39 is pivotally connected between ears 40 intermediate the length of the handle 33, by a --l the hinge pin 29, The upper end of the lever 30 is then moved rearwardly and as the spring 38 is compressed the handle 33 of the switch 2| is moved to its rear position. In the rear position of the handle 33, the circuit to the motor I2 is broken and the electric circuit to the alarm 24 is completed. When the switch 2| is reset by the movement of the switch 33 to its original position, the alarm circuit is broken and the motor circuit re-connected. The spring 38 is normally slightly compressed with the switch 2| in the motor circuit position. When the handle 33 is in the position for closing the circuit to the alarm, there still remains some tension on the spring 38 for urging the cover I8 back to the closed position.

I do not mean to confine myself to the exact' details of construction herein disclosed, but claim all variations falling within the purview of the appended claim, a 1

What I claim is:

, Switch operating mechanism for a safety system for a. furnace having a blower motor, a blowout pipe, a pivoted cover therefor, and a double throw switch closing a blower motor circuit in one position thereof and opening said motor circuit and closingan alarm circuit in another position thereof; comprising a housing for mounting on the blow-out pipe adjacent the pivoted cover and engageable over the switch, a lever rockably carried by said housing and having one end adapted for connection to the pivoted cover, a rockable handle having one end adapted for connection to the switch, an opening formed through the other end f said handle, an actuating rod pivotally connected at one end thereof to the other end of said lever, a portion of reduced thickness formed on the other end of said rod slidably extending through said handle opening, a coil spring member disposed about said portion of said rod and bearing against said handle, and a reset rod extending slidably through a wall of said housing and having the inner end thereof pivotally connected to said handle. 1

POMPEO M. SANTULLO.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 978,849 Collier Dec. 20, 1910 1,564,207 Cloud Dec. 8, 1925 1,582,064 Maddox Apr. 27, 1926 1,886,854 Vogt Nov. 8, 1932 2,111,431 Lum Mar. 15, 1938 2,469,082 Scanlon May 3, 1949

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