US 1338928 A
Description (OCR text may contain errors)
J. M. HOPWOOD.
REGULATION AND APPARATUS THEREFOR. APPLICATION FILED APR. 21-, 1919.
1,338,928. Patented May 4, 1920.
2 SHEETS--SHEET 1- INVENTOR M 1 WW J. M. HOPWOOD. REGULATION AND APPARATUS THEREFOR. APPLICATION FlLED APR.21, 1919.
1,338,928, Patented May 4, 1920.
2 SHEETS-SHEET FIELEI- a8 1 m i I 7 45 38 o o o i H 5 2 a6 I 1 g Q l l I WITNES SES I O INVENTOR UNITED sTArns TENT OFFICE.
JOHN M. HOZEWOOID, 0F DORMONT, PENNSYLVANIA,
REGULATION AND APPARATUS THEREFOR.
Specification of Letters Patent.
. Patented Ma 4, 1920.
Application filed April 21, 1919. Serial No. 291,780.
To all whom it may com-cm:
Be it known that I, JoHN M. Horwooo, residing at Dormont, in the county of Allegheny and State of Pennsylvania, a citizen of the United States, have invented or discovered certain new and useful Im rovements in Regulation and Apparatus herefor, of which improvements the following is a specification.
The invention described herein relates to the regulation of combustion conditions such as supply of fuel and air for the proper combustion of fuel and the pressure of gases in the furnace of vapor generators where a fluid, as gas or oil, is employed and the invention has for its object the regulationof the supply of this fluid fuelto the furnace by and in accordance with changes in the rate 1 of flow of vapor from the generator or with changes in the static pressure of the vapor or with changes in both the dynamic and static pressures of vapors flowing from the generator, controlling the supply of air by and in accordance with the rate of supply of fluid fuel and controlling the discharge of products of combustion by and inaccordance with the pressure of gases in the furnace. The invention is hereinafter more fully described and claimed.
In the accompanying drawings forming a part of this specification, Figure 1. shows diagrammatically suitable means for controlling combustion where gas is employed as the fuel, Fig. 2 is a view showing a modification in the fuel control and also a modification in the air control when oil is employed as fuel and Fig. 3 is a sectional elevation of a form of apparatus preferably employed when the supply of 'fuel is controlled bystatic pressure of vapor in the boiler. I
In the practiceof the invention-the pipe 1 through which gas is supplied to the furnace of the generator. is provided with a valve 2 for regulating such supply. This valve is operatively connected to mechanism adapted to be operated by-and in accordance with changes in therate of flow of vapor from the generator or by and in accordance with changes in the static ressure of-the' vapor or by and in accor ance with changes in both the dynamic and static pressures of vapor. flowing from the generator: It is preferred for'this purpose to employ mechanism shown a'nd described in application Serial No. 254975, filed September 20, 1918. This mechanism embodies a diaphragm indicated at 5 and subjected on its upper side tothe total pressure of vapor flowing from the generator through the conduit the chamber above said diaphragm being so'connected by a pipe 11 and Pitot tube 'or its equivalent to the-conduit that the pressure exerted on the diaphragm will be equal to the static pressure in the generator. plus or minus the pressure due to the rate of flow of vapor from thegenerator. A chamber intermediate the diaphragm 5 and a second diaphragm indicated at 6 is so connected to the generator or the conduit C that the pressure maintained in said chamber will be equal to the static pressure of n'ected' as described and shown in the above application, to a pilot valve controlling the flow of fluid under pressure to the cylinder 28 that for every change in the rate of flow of the vapor or for every change vin the static pressure of the vapor or change in both, the pilot valve will be opened proportionally to such change, thereby causing a movement of the piston in said cylinder and the-frame 29 carried thereby and connected by suitable means as the rope 4 to the valve 2 in the gas supply pipe 1. Suitable compensating mechanism operative by the frame 29 is employed for closing the pilot valve after a predetermined movement of the frame. The frame is shifted its predetermined movement in one direction or the other, dependent upon whether the changes in the dynamic or the static pressures or both in the conduit C are up or down. but in all cases an increase in the static pressure and a decrease in the rate of flow willeflect through the describedmech anism a closing movement 'ofthe regulating valve 2 proportional to such changes-and increase in the rate of 'flow or decrease in static pressure will cause ment of the valve 2. q
The air for the combustion of the as is introduced into the furnace throu' the conduit'7. air-being forced throu h t e conduit by a blower 8 whi'chis re erabl y operated at" a constant speed. T is uniformity a reverse moveof feed of air is preferably attained bysup plyingthe motor of the fan or blowerwlth steam at a constant pressure below the normal or working. pressure in the" generator. To this end steam is-supplied to the pipe 9 which is connected to the motor of the quantity of fuel to be fed to the furnace-and the proportioning of air to be fed to the amount of fuel 'actuallyfed' at any one time will beefiected by a valve 11 arranged in the air conduit and adapted to be controlled by and in accordance with the pressure of fuel in the supply pipe at a point intermediate the valve 2 and the furnace. The mechanism for operating the valve .11- consists of a tank 12 containing liquid in which two inverted cups 13 and 14 are immersed; said cups being secured to a lever 15 on the opposite sides of the pivotal point of the lever. A nozzle 16 connected by a pipe 17 to the gas supply pipe 1 projects upinto one of the cups as 13 to-a point above the level of the li uid in the tank, so that the interior of t ecup will be subjected to any changes in the pressure of gas inthe pipe 1 between the control valve and furnace and will rise or fall with such changes. The movement of the cup'13 will impart an opposite movement to the other cup 14, and'as fully set forth said application, this cup will effect the displacement of the body of liquid inclosed therein, relative tothe liquid exterior of the cup, and such displaced body ofliquid will automatically counterbalance the pressure in the cup 13, thus insuring a movement of the cups and the lever propor tional to each incremental change in the pressure of gas in the pipe 1. The lever is connected by suitable means to a valve mechanism controlling the flow of fluid under pressure to the cylinder 18', having its piston connected by suitable means as a cord 19 t0 the valve 11 in the conduit 7. Suitable compensating mechanism o erative by the pis-- ton is employed for closing the valve opened by the lever, on a predetermined movement of the piston, as fullg' in the a plication rial.
the rate of discharge should be so regulated as to insure amaximum utilization of the heat generated. To these ends provision is made for regulating the escape or outflow of the products of combustionproportion- Y ally to1the rate of combustion and to maintain a pressure of gases in the furnace not at all times suflicient air for the maxidescribed and shown v Number 254,975 above re erred to, so that the valve 11 will be shifted to .vary the supply of air propor- L greater than-and referably below atmospheric pressure. hile a stack maybe employed for drawing products of combustion from the furnace, it is preferred to employ an exhaust fan 20, operating at a rate which is constant but sufliciently high to withdraw gases when the generator is operated at its maximum rating. To attain these operating conditions, the motor of the fan is constructed to drivethe fan at its maximum speed, with a steampressure' lower than the normal working pressure in the generator-" In the construction shown, the motor of the exhaust fan 20 is connected to the pipe 9, which, as heretofore stated, is connectedto thegenerator through a reducing valve 10. As the exhaust fan will 0 erate to remove gases when the generator 1s working at its maxlmum rate, suitable means as a damper. r
21 are employed to regulate the discharge of gases when the generator is operated at a lower rate and such damper iscon'trolled== by means operative byand in accordance with the pressureof gases in the furnace- While any suitable means may be employed for this purpose, it is preferred to use, as.
shown at A, mechanism similar to that employed for controlling'the valve 15? in the air conduit 7, the nozzle 16 of such mechanism being connected to the furnaceby a pipe 22 and the piston of the cylinder 18 connected to the valve'or damper'21 by any suitable means as. the cord. 23.
In such cases a mechanism such as'that I shown in Fi 3 is p'referabl employed, such mechanism 7 in describe and claimed in application Serial Number 249654 filed August 14th, 1918,. by Thomas A. Peebles.
As'shownin Fig. 3, theprime motor consists of a diaphragm 29 arranged in a shell *or casing 30 and referably con'strudted as shown and described in, Letters Patent No. 1094116 granted April 21st, 1914 to Francis H. Brown. The shell is so connected'b a pipe 31 to the outlet. pipe C of the boller that one. side of the diaphragm will be subjected to the-static pressure of the vapor' in thegenerator. The opposite sideo fthe diaphragm is subjected-to a fluid pressure equal to the normal working or static pressureo vapor in the outlet p pe. This pressure i applied through a fluid cushion formed in chamber 32' communicating with the underside of the shell or casing 29 through a port 33. An inverted cup 35 is arranged in the chamber which is then filled with liquid through 'a port 36 whichjs then closed by a suitable plug. In filling this chamber, air willbe trapped in the cup thereby forming a resilient cushion. To establish the desire pressure under the diaphragm, communication is established between the chambers on opposite sides of the diaphra by opening the valve in said passage.- fter an ualization of pressure on op 'te sides 0 the diaphragm, the valve controlling the passage is closed so that thereafter one side of the diaphragm will be subjected to the pressureof the air cushion or the normal static pressure in the generator. The pressure onboth sides being equal, any change in the static pressure in the generator will increase or decrease the pressure on the upper side of 7 mounted standard 43. lVhen the beam is shifted by the diaphragm, the bell crank lever will move with it ndthereby shift the movable member of the pilot valve and admit pressure to one-end of the cylinder 28 to move its piston which is connected to the frame 29. One of the legs of this frame has a block secured thereto on which is adjustably mounted a bar 46 which is adapted to slide along a shoe pivotally mounted on the upper end of the pivotally mounted standard. This bar can be adjusted to any desired angle to the axis of the .cylinder 28 so that by any desired movement of the frame the swinging standard may be moved sufliciently to so shiftthe bell crank lever as to close the pilot valve which has been .opened by the movement of the beam operative by the diaphragm. It it characteristic of the construction employed that for each movement ,of the diaphragm an incremental movement will be imparted tothe frame 29. On any variation of static pressure in the 7 generator, the frame 29 will be shifted thereby shiftingthe valve 2 in the gas sup- P y p p Vhen employing Oll as a fuel, the mecl1anism employed for operating the air controlling valve 11 is adapted to be operated by and in accordance with changes in the rate of feed of oil to the furnace, a mechanism similar to that shown in Fig. 3 can be employed for controlling the valve 11in the air supply duct as indicated in Fig. 2,
by connecting the chamber above the diaphragm 6 to the oil supply pipe and establishing below the diaphragm a pressure substantially equal to, the normal pressure in the oil supply pipe.
It is characteristic of the improvement described herein that the supply of fluid fuel is regulated by and in accordance with the changes in the rate of flow of vapor from the generator or by and in accordance in the furnace of a vapor generator utilizing a fluid fuel which consists in controlling the feed of the fuel by and in accordance with changes in the rate of flow of vapor from the generator and by and in accordance with the changes in the static pressure of the vapor in the generator and regulating the supply of air for combustion by andin accordance with changes inthe quantity of fuel fed to the furnace.
2. The method of regulating combustion in the furnace of a vapor generator, utilizing' a fluid fuel which consists in controlling the feed of .the fuel by and in accordance with changes in the rate of flow of vapor from the generator and by and'in accordance with changes in the static pressure of the I vapor'in the generator, regulating the supply of air for combustion by and in accord ance with changes in the quantity of fuel fed to the furnace, and controlling the discharge of gases by and in accordance with changes in the pressure of gases in the furnace.
3. The method of regulating combustion in the furnace of a vapor generator, utilizing a fluid fuel which consists in controlling.
the feed of the fuel by and in accordance with changes in the static pressure of the vapor in the generator and regulating the supply of air for combustion by and in accordance with changes in the pressure of fuel fed to the furnace.
4. The method of regulating combustion in the furnace of a vapor generator utilizing fluid fuel which consists in regulating the supply of air for combustion by and in accordance with the changes in the pressure of fuel fed to the furnace and regulating the discharge ofgases from the furnace by and in accordance with the pressure in the furnace.
In testimony whereof, I have hereunto set my hand.
JOHN M. HoPwooD.