US715919A - Draft and damper regulator for furnaces. - Google Patents

Description

Nn. 715,919. Patented Dec. le., |902.

l w. F. wlLMoTH. y

DRAFT AND DAMPEB REGULATUR FOR FURNACES.

(Application led Mar. 5, 1902.)

(No Model.)

UNITED STATES l PATENT OEEICE.

WILLIAM F. WILMOTH, OF NEW YORK, N. Y., ASSIGNOR TO AMERICAN FURNACE COMPANY,A OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

DRAFT AND DANIPER REGULATOR lFOR FURNACES.

SPECIFICATION forming part of Letters Patent No. 715,919, dated December 16, 1902.

Application fled March 5, 1902.

To all whom, it may concern:

Beit known that I, WILLIAM FRANKLIN WILMOTH, a citizen of the Uuited States, residing in New York, in the county and State of New York, have invented certain new and useful Improvements in Draft and Damper Regulators for Furnaces; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to improvements in draft and damper regulators for furnaces; and it consists in means for automatically closing a furnace-damper when the re-door is opened, for automatically opening such damper to the fullest extent when theflredoor is again closed, andV then for gradually moving the damper to a partially-closed position.

My invention consists also in the novel construction of the damper-operatingdevice.

In the operation of furnaces it is highly important that the damper in the furnaceoiftake shall be closed when the {ire-door is opened, so that the inrush of air, which would otherwise take place, may be prevented. Such inrush of air chills the heating-surface of the boiler and carries away a large amount of heat, besides subjecting parts of the boiler to considerable strain because of the sudden change of temperature. It is of coursenecessary that the damper shall be opened immediately' after the furnace-door is closed in order that the draftmay be restablished. When the fire is fresh, the damper should be open to the widest possible extent; but after the fresh coal has become heated and partially coked and the volatile constituent-s of the coal have been driven off considerable increase in economy maybe effected by partially closing the damper in the furnace-otake, so as to decrease the draft. In practice it is found that the furnace attendants cannot be relied upon to operate such dampers by hand, and in practice no attention is paid to the opening and closing of the damper at the time of firing.

The objects of my invention are to increase serial no. 96,850. ino man.)

the efficiency of furnaces, to supply to a furnace only the quantity of air required for goed combustion, and so to avoid the admission of an excess of air, to close and open the furnace damper or dampers when the fire-door is opened or closed, to open the furnace-damper wide when the fire-door is first closed, and then to move such damper to a partially-closed position after the fresh fuel has become heated, and to make the apparatus as simple, compact, reliable, and inexpensive as possible.

I will now proceed to describe my invention with reference to the accompanying drawings, in which one form of apparatus embodying my invention is illustrated, and in which- Figure 1 is a front elevation of a boiler, showing my improved damper-regulating apparatus in place thereon. Fig. 2 is a side View of such apparatus, and Fig. 3 is a vertical sectional view of such apparatus.

In the drawings, 1 indicates the fire-door of a boiler-furnace; 2, the offtake thereof; 3, a damper in the offtake, provided with a 'weight 4 tending to hold the same open normally, and 5 an arm by which said damper may be operated. The damper operating apparatus comprises a hydraulic cylinder and piston, the piston-rod of which is connected by a cord or chain 6 to the said damper-operating arm '5, and suitable valves regulating the flow of water to the said cylinder. 7 designates the said cylinder, 8 the piston thereof, 9 the piston-rod, and l0 a tray upon said piston-rod adaptedto receive weights by means of which when the piston is permitted to descend the damper may be pulled shut against the resistance of its weight 4. The piston-rod 9 projects through a stufng-box on the lower end of the cylinder and is connected by means of a bracket 11 to a valverod 12. Said valve-rod has a sliding connection with a sliding valve 13, mounted within a valve-casing 14, having stuffing-boxes at both ends through which the said valve works. Such sliding connection is produced by providing the valve-rod 12 with a head 15 and entering the same within a bore 16 in the upper portion of the valve closed by a cap 17. A pipe 18 connects the valve-casing 14 with any suitable source of Water-supply. Another pipe 19 connects said valve-casing with an orifice 2O near the bottom of the cylinder 7. In the valve 13 is a port 2l, which when opposite pipes 18 and 19 places the same in communication. Another pipe 22 connects the said orifice 20 of the cylinder 7 with a valve 23, connected by a stem 24 to the pintle of the fire-door. This Valve 23 may he of the ordinary turn-plug type and is arranged to be opened when the furnace-door is closed.

In Figs. 2 and 3 the parts are shown in the positions they would occupy if the furnacedoor has just been opened. The piston 8 is near the bottom of the cylinder 7, the damper is closed, the port 21 of the valve 13 is connecting pipes 18 and 19, and the valve 23 is open, so that Water flows from pipe 18 through pipes 19 and 22 and valve 23 to waste. If now the furnace-door be closed, valve 23 will be closed and the pressure of the Water entering the cylinder 7 from pipe 19 Will raise the pistou S against the pressure of the Weights on its piston-rod, permitting the damper to close. In its upward movement the piston overrides a leakage-port 25, which may be provided with any suitablel regulating-valve. When the piston is near the upper limit of its stroke, the head 15 of valve-rod 12 encounters the cap 17 of sliding valve 13 and lifts the same, thus cutting oi the supply of Water. The weights on the piston-rod 9 will then cause the piston to descend slowly, the rate of closing being determined by the rate of escape of water through the leakage-port 25,thusgradually moving the furnace-damper toward the closed position until finally the piston overrides the leakage-port 25. This cuts o the escape of water, and the piston will then stand at such position until the firedoor is again opened. Vhen this takes place, valve 23 isopened, the Water in cylinder 7 beneath the piston is permitted to escape to waste, the piston descends, thus closing the damper, and as the piston nears the lower limit of its stroke the head 15 of valve-rod 12 encounters the sliding valve 13'and pushes the latter down, thus again turning on the water by which the device is operated.

Valve 23 constitutes the controlling device of the apparatus, and port 25 constitutes a secondary controlling device or slow-closing means.

The action of the device may be regulated by regulating the rate at which Water may escape through leakage-port 25. The location of this port determines what will be the normal position of the damper. Such normal position Will obviously be between the closed position and the Wide-open position and will be the position best adapted for normal operation. This avoids drawing into the Obviously the cylfurnace an excess of air.

inder may be provided with a plurality of such leakage-ports located at different heights,and thus by opening one or the other of these ports the normal position of the damper may be regulated.

It :is obvious that my invention may be operated by other iluids under pressure besides water-such, for example, as steam or compressed air. It Will be noted that since the valve 13 passes through both ends of the valvecasing it is perfectly balanced and has no tendency to move of itself.

It is obvious that my invention is susceptible of many modifications and changes in construction and arrangement of the parts and in operation Without departing from the basic principles of the invention, and I do not limit myself to the particular construction ot' the device herein illustrated and described.

What I claim is- 1. In a damper-operating apparatus, the combination with a motor for operating a damper, adapted to open and close the damper or to hold it in an intermediate position, of automatic controlling means for said motor arranged to cause the same to close the damper, to open the same, and to move the same automatically to, and maintain it at, an intermediate position subsequent to the opening thereof.

2. In a damper-operating apparatus, the combination with a motor for operating a damper, adapted to open and close the damper or hold it at an intermediate position, of automatic controlling means for said motor arranged to cause the same to open and close the damper, and comprising slow-closing means arranged to cause the motor, after each opening of the damper, to move the same gradually to a partially-closed position and maintain it there.

3. In a damper-operating apparatus, the combination with a motor for operating a damper, of primary and secondary controlling means therefor, the primary means arranged to cause said motor to operate to open or close the damper, according to the Way said controlling means is operated, the secondary controlling means arranged to cause said motor, after each closing of the damper, to move the same to an intermediate position and to maintain it there.

4. In a damper operating apparatus, the combination with a chamber having valvecontrolled means for supplying fluid under pressure thereto and permitting exhaust of such fluid therefrom, and having also secondary escape means permitting relatively slow escape of Huid therefrom While normal exhaust is prevented, of a movable Wall for said chamber arranged to closesaid escape means at an intermediate point in its movement.

5. In a damper operating apparatus, the combination with a chamber having supply and exhaust valves and secondary escape IOO IIO

means permitting relatively slow escape of fluid therefrom while normal exhaust is prevented, of a movable wall for said chamber operating the supply-valve and likewise arranged to close said escape means at an intermediate point in its movement.

6. In a damper-operating apparatus, the combination with a chamber having separate supply and exhaust valves and secondary escape means permitting relatively slow escape of fluid therefrom, While normal exhaust is prevented, of a movable Wall for said chamber operating the supply-valve and likewise arranged to close said escape means at an intermediate point in its movement.

7. In a damper-operating apparatus, the combination with a cylinder having valvecontrolled means for supplying iiuid under pressure thereto and permitting exhaust of such fluid therefrom, and having also secondary escape means permitting relatively slow escape of iuid therefrom while normal exhaust is prevented, of a piston for said chamber arranged toiclose said escape means at an intermediate point in its movement.

8.l In a damper-operating apparatus, the combination with a cylinder having supply and exhaust valves and secondary escape means permitting relatively slow escape of Huid therefrom While normal exhaust is prevented, of a piston for said cylinder operating the supply-valve and likewise arranged to close said escape means at an intermediate point in its movement. y

9. In a damper-operating apparatus, the combination with a cylinder having separate supply and exhaust valves and a secondary escape-port permitting relatively slow escape of iiuid therefrom while normal exhaust is prevented, of a piston for said cylinder operating the supply-valve and likewise arranged to override and close saidv escape-port at an intermediate point in its movement.

10. In a damper-operating apparatus, the combination With a cylinder and a piston therefor, of supply and exhaust valves automatically operated, and a secondary escapeport which is open when the piston is at the outer end of `said cylinder and is overridden and closed by the piston during its motion inward.

ll. In a damper-operating apparatus, the combination with a cylinder and a piston therefor, of supply and exhaust valves automatically operated, the former by the motion of the piston, and a secondary escape-port which is open when the piston is at the outer end of said cylinder and is overridden and closed by the piston during its motion inward.

12. In a damper-operating apparatus, the combination With a cylinder and a piston therefor, of supply and exhaust valves automatically operated', the latter arranged to be operated by connection to afurnace-door, and a secondary escape-port which is open when the piston is at the outer end of said cylinder and is overridden and closed by the piston during its motion inward.

13. The combination with a furnace, and a damper therefor, of a damper-operating apparatus comprising a damper-operating motor arranged to open and close` said damper or to hold the same in an intermediate position, and automatic controlling means for said motor arranged to cause the same to open and close the damper and move the latter to an intermediate position after each opening thereof.

14. The combination with a furnace, and a damper therefor, of a damper-operating apparatus comprising a damper-operating motor arranged to open and close said damper or to hold the same in an intermediate position, a controlling device for said motor automatically operated `upon the opening or closing of the furnace-door, and arranged to cause said motor to close or open said damper according as the furnace-door is opened or closed, and secondary controlling means arranged to cause said motor to partly close the damper and hold the same in such position, after' each closing of the furnace-door.

In testimony whereof I afx my signature in the presence of two witnesses.

WILLIAM F. WILMOTH.

/Vitnesses:

WILLIAM D. ADAMS, HARRY M. MARBLE.

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