US2113001A - Gas burner - Google Patents

Description

Ap 5, 1938. l.. l.. scoTT 2,113,001

GAS BURNER Filed Nov. 18, 1935 2snee1s-shee1- 1 April 5, 1938. l L; SCOTT 2,113,001

GAS BURNER Filed Ndv. 1e, 1935 2 sheets-sneer 2 Patented Apr. 5, 1938 UNITED STATES PATENT OFFICE 8 Claims.

This invention relates to gas burners of a type particularly adapted for household heating, although its utility is not limited to that use. v

An object of the invention is to provide a gas 5 burner with meansl for opening and closing a gas supply line which is simple in construction, durable in service and economical in operation.

.Another object of the invention is to provide a gas burner with valve mechanism for opening and closing the supply line which will be so arranged that the use of packing about the valve is unnecessary. More specifically, an object is to provide a valve having a stem opening into an air conduit or chamber in such a fashion that any small amount of gas leaking past the valve and past its stem, due to irregularities of construction or wear, -will be discharged into the furnace where it may be ignited by a pilot and thereby consumed.

Another object of the invention is to provide means simple in construction and durable in service to simultaneously close a gas Valve, and to close an air mixing valve, whereby air may be prevented from entering the furnace when the burner is out of operation,

Another object of the invention is to utilize a motor which is provided for furnishing a forced draft of air to the gas burner, also to open a gas supply valve when the motor is placed in operation. In accordance with the preceding objects vsuch a device may also be applied to simultaneously open the air mixing valve if desired. Thus, a single electric circuit supplying the motor and controlled by a room thermostat, for instance, may fully control the operation of the burner. 4

Other objects will be apparent from the following descripton, taken in connection with the accompanying drawings.

Fig. 1 is a vertical section showing an embodiment of my invention;

Fig. 2 is a bottom view;

Fig. 3 is a detail partly in section showing a clutch which is a part of the embodiment; and

Fig. 4 is acircuit diagram.

A furnace or boiler I to be heated, which may be of any selected construction, has an opening 2 in which the burner may be installed. The burner includes a shell or casing 3 having an annular chamber or conduit 4 which communicates through an extended portion 5 and a port 6 with valve housing l, connected to a gas supply line 8. The casing 3 has an inner annular Wall 9 forming a cylindrical chamber or conduit with a perforate bottom yWall I0, which supports a motor II, having a shaft I2 extending through the Wall and driving an air propeller I3 positioned inside the cylindrical Wall or chamber 9.

The outer end of the motor shaft I2, through a chain of reducing gearing, drives a shaft I4 at a low` speed. An iron disc or armature I5 is fixed to the shaft I4 and forms a part of a magnetic clutch for opening and closing a poppet valve I6 in the port 6, and for shifting a perforate damper plate II, which is so arranged with respect to the perforate plate I0 as to form an air mixing valve or damper for the chamber 9.

The valve I6 seats in the port 6 and its stem I8 extends through the annular wall 9 with its outer end exposed for engagement by a lever I9. The valve is closed and normally held in closed position by an expansion spring 20.

The lever I9 is connected by a link 2I to the damper plate II and is connected by a link 22 to a clutch stator 23, pivotally mounted on the shaft I4 to cooperate with the clutch armature I5. The stator 23 is energized by a coil 24 connected by Wires 25 to a supply circuit 26 for the motor.

Hence, when the motor is not operating, the spring 20 Will close the fuel valve I6, thus moving the lever I9 to close the damper plate I'I. The air chambers will be closed at the bottom and any gas leaking through the valve and its stern Will flow into the furnace. When current flows through the circuit 26, responsive for instance to the operation of a room thermostat 2l, the motor and its blower I3 will start operation, and the coil 24 will cause engagement of the magnetic clutch to operate the lever I9 and thus open the damper plate Il and the valve I6.

The foregoing is a short description of the embodiment of the invention specifically shown in the drawings, while the essential features of the invention are pointed out in the appended claims. The following supplemental description of the construction and operation of the embodiment specifically illustrated will assist in understanding and practicing the invention.

The burner casing is provided with a burnerv opening comprising an annular slot 30 through the wall forming the annular chamber 4. A mushroom deflector 3| is spaced from the top Wall of the burner casing by means of legs 32. Thus, air passing through the chamber or conduit 9 is deflected toward the burner opening 30. A pilot 33, as specifically shown, is fed by gas from thechamber 1. The casing 3 is supported in the opening 2 and above a floor upon which the furnace may be placed by legs 34.

The damper, as previously described, includes a fixed perforate plate I0, and a movable plate Il. The plate I0 is held in position by a number of screws 35, each engaging in the casing and having a shoulder portion adjacent the head, the

shoulder engaging the plate I0 and holding it securely in position while the head is spaced` from the plate to provide a guide for the movable perforate plate Il. The motor II is supported by bolts 36 to the plate I0, while the plate II has appropriate arcuate slots to accommodate the supports. The extent of opening of the damper plate I1 may be regulated by an adjustable stop 31, having an abutment piece 38 for engagement with a lug 39 secured to the plate 4l1. The stop 31 is held in position by a screw 40 on the casing 3 and passing through a slot 4I in the stop member 31. Thus, the stop member 31 may be held in a number of positions depending upon the setting of the screws 40 in the slot 4I.

The lever I9 includes an arm l2, which engages the end of the valve stem and an arm I3, to which is attached links 2| and 22, the arms being adjustably positioned on a shaft M which is supported by a bracket 45 attached to the casing 3. The levers are adjustable on the shaft M in order to provide a proper valve clearance regardless of the adjustment of the stop 31 for the damper.

The shaft Il, to which the clutch disc I5 is attached, is driven through reducing gearing, not shown, by the motor shaft I2. The details of the gearing are not shown because it forms no part of the present invention and its construction, which may be varied, is well understood in the art. It may be of the type commonly used for driving oscillating mechanism in electric circulating fans, and rotates at substantially the same speed, that is to say, between 4 and 5 R. P. M. If the burner is to be used for heating, the motor circuit will ordinarily be controlled by a room' thermostat 21, shown diagrammatically in Fig. 4. That is to say, when the temperature of the room falls below the temperature for which the thermostat may be set, the motor circuit will be closed and themotor pnt inoperation. The operation of the motor rotates the shaft I4 and since the coil 2l of the magnetic clutch is connected to the motor circuit, mnvement of the disc I5 will tend to move the clutch element 23 to rock the lever I9 and open the valve I8 and the damper plate I1. Rotation of the disc 23 `will continue until the damper plate I1 is opened and the lug 33 engages the abutment piece 33 on the stop member 31. Thereafter, during operation of the motor the clutch will slip but hold the valve and damper open.

Upon a predetermined rise in temperature the thermostatic switch will be opened, thus stopping the motor and releasing the clutch element 23. Thereupon the `expansion spring 20 will press the valve I3 closed and move the lever 42, thus closing the damper plate I1. Any gas which might escape around the valve, due' to wear or faulty workmanship, and from the chamber 5 around the valve stem into the chamber I will be trapped by the shutter I1 and will now into the furnace under the mushroom deilector 3| where it may be ignited by the pilot 33. Furthermore, draft will be prevented from flowing through the air-duct 3 and thus unnecessarily cooling the furnace when the burner is oiI.-

From the foregoing it is obvious that the invention accomplishes its purposes. i Parts of the invention may be used without -the whole and various changes may be made in the details of construction, vwithin the scope 4of the appended claims, without departing from the spirit of this invention.

I claim:

1. A gas burner having a supply port, a gas conduit leading from the port to a burner opening, an air conduit adjacent said gas conduit leading from atmosphere to said opening, a valve for opening and closing the port and having a stem extending through a wall separating said conduits, a damper for closing said air conduit, ar blower in the air conduit, a motor for driving the blower, mechanism for operating the stem and the damper, and a clutch for connecting the motor and the mechanism arranged whereby the motor upon starting will operate the mechanism and upon stopping will release the mechanism;

2.v In a gas burner, a blower, a motor for operating the blower, a gas supply valve, mechanismfor opening the valve, a magnetic clutch for connecting when energized the motor and said mechanism, a-common circuit for energizing both the motor and clutch, and resilient means for closing the valve, whereby the valve will be opened and held open upon operation of the blower and closed when current is cut on.' from the motor.

3. In a gas burner, a motor, a gas supply valve, yielding means for normally holding the valve closed, mechanism for opening the valve, and a clutch device for connecting the motor and said mechanism arranged whereby the motor upon starting will operate the mechanism and upon stopping will release the mechanism.

4. In a gas burner,'a draft damper, a gas supply valve, a lever, an operating connection between said lever and damper, an operating connection between the lever and the valve, arranged whereby the lever will open the valve and damper, a blower, a motor for operating the blower, mechanism for operating the lever, and a 5. Apparatus for operating aI supply valvel comprising, yielding means for closing the valve, mechanism for opening the valve, an electric motor, a magnetic clutch adapted when energized to connect the motor and said mechanism, and a common circuit to supplyl said motor and to actuate said clutch.

6. Apparatus for operating a supply valve comprising, yielding means for closing the valve, mechanism for opening the valve, an electric motor, a slip clutch adapted to connect the motor and said mechanism, and arranged by slipping to permit continuous operation of the motor during the period said valve is open and to permit the yielding means to close said valve when the motor is stopped.

7. Apparatus for operating a supply valve ccmprising, an electric motor, reducing gearing operable bythe motor, mechanism for .opening the valve, a slip-clutch associated with` said gearing to actuate saidmechanism and adapted by slipping to permit continuous operation of the motor while the valve is open, and means independent of said gearing and motor .operable to close said valve when the motor is stopped.

8. Apparatus for operating a supply valve coni'- lprising, yielding means for closing the valve,

mechanism-for opening the valve. an electric motor, reducing gearing operable by the motor.

.a magnetic clutch adapted when energized to Said motor 8nd t0 actuate Said clutch.

LEWIS L. SCOI'I.

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