US2698141A - Controlling apparatus - Google Patents

Description

Dec. 28, 1954 P. s. DICKEY ETAL 2,698,141

CONTROLLING APPARATUS Original Filed 'Apri1-26, 1946 3 Sheets-Sheet 1 III llll IH FIG. I

3nvcntors PAUL S.- DICKEY AND JACK F. SHANNON P. S. DICKEY ETAL Dec. 28,1954

CONTROLLING APPARATUS 3 Sheets-Sheet 2 Original Filed April 26, 1946 FIG. 2

FIG. 3

3nventors PAUL S. DICKEY JACK F. SHANNON AND Dec. 28, 1954 P. s. DICKEY ETAL CONTROLLING APPARATUS 3 Sheets-Sheet 5 Original Filed April 26, 1946 i M T moss mmEIaEd Jo -.200 10b0,: QZ mwEjmsE INVENTORS, AND PAUL s. DICKEY BY JACK F. SHANNON 4 Q THEIR A m'm' United States Patent C ON TROLLING APPARATUS Paul S; Dickey, East Cleveland, and; Jackv F.. Shannon, Euclid, Ohio, assignors. toBailey Meter Company,.a corporation of Delaware Original application April'26, 1946, Serial No. 665,108. and this application June 28, 1952, Serial No.

4 Claims. (Cl. 236-) Our invention relates to fluid control systems, and more particularly to flow measuring and control" systems for recirculating oil burner installations.

An object of our invention is to provide an improved system which operates automaticallyto regulate the supply of fuel, such as oil, from a burner to a furnace. Another object is to. provide an improved recirculating oil system for the burner of a furnace. Another object is to provide for a furnacean improved recirculating oil system having means for supplying oil to aburner at a fixed rate and for regulating theflowof oil from the burner to a return line in inverse proportion tothe flow of air through the furnace. Yet another object. is to provide in an improved system for a recirculating burner installation, means for supplyingrfuel' from the burner to a furnace in proportion 1031116: flow of air therethrough, and means operating automatically when it becomes desirable to extinguish the flame in the furnace, to deliver the oil in a predetermined manner through conduits by-passing the burner. Yet another object. is to provide improved. means for'indicating the. flow of oil in a recirculating burner installation. 'Another ob.- ject is to provide an improved recirculating burner in.- stallation having means responsive to the. flow of air through a furnace and to the difference in flow between fuel supply and return lines. for controlling the distribution of fuel from the burner .to the furnace and the return line. Other objects will appear in the. course. of the following description.

This application is a division of our pending. application Ser. No. 665,108 (now abandoned) filed April 26, 1946, as a continuation-in-part of our application S.;N-. 555,258, filed September 22, 1944, and now Patent No. 2,459,689 dated January 18,. 1949.

In the accompanying drawings in which there .is shown for purposes of illustration. one form which our invention may assume in practice:

Fig. 1. is an enlarged vertical sectionalv view of. a flow meter which is adapted for use in our improved control system.

Fig. 2 is a diagram of the. piping, and fluid control means included in our control. system.

Fig- 3 is a wiring diagramfor electricalcontrol apparatus used in the control system shown in Fig. 2.

Fig. 4 shows diagrammatically. our complete control system.

It will be understood that the parts -in each of the figures of the drawing are not-shown to scale. In Figs- 2 and 4 a fuel oil burner 1, shown to greatly enlarged scale relative to the rest of the system, has oil supplied thereto througha pipe 2 connected througha 3-way valve 3 and a flow meter or device 5 which operates indirect proportion to the flow of oil therethrough,..to the discharge of a fuel pump 6 which is driven by suitable means, not shown, and operates. to supplyfuel oil to the system at a constant rate. .The burner. has a part8 through which a portion of the oil. is discharged to be burned in a furnace 9, shown. in Fig. 4. The rest of the oil supplied to the burner is. discharged past a check valve 10,. a diaphragm-actuated valve 12 and a'flow responsive device or meter 5A to a return pipe 14 leading to a fuel tank, not shown, or to the intake side of the pump 6. The oil is supplied to the burner under normal operating conditions at a pressure of approximately 1000 p. s. i., and, to prevent the pressure from exceeding this value at any time, there is provided acrossthe pump a lay-pass 16 containing a pressure regulating valve 1'7;

By regulatingthe valve 12'to restrictinavarying amounts 2 ,698,141 Patented Dec. 28, 1954 ICC the flow of oil from the burner to the return line 14, it. will be seen that the amount of: oil discharged from theburner. through the port 8 to be consumed .in the furnace'will be correspondingly varied. For regulating the :valve 12.we have: provided a system which: is responsive to changes. in .the how of: air throughthe: furnace and: to changes inthe difference between the flow of oil from the pump discharge and the flow through the re turn line 14. This regulatingnsystem includes a conduit 18 communicating at one end with 'a. diaphragm 19' for the .valve 12, and communicating at its other end with a valve casing 20 containinga valve member 21. which isoperatively connected tothemid portionof a lever 22. The valve member operates. to control the connection of the conduit 18 with a fluid supplyv conduit 23 and a fluid discharge conduit 24. In a neutral position of the valve member, the-conduit 18 is. cut oil? from both the fluid supply and discharge conduits. When the: valve member is moved upwardly in Fig, 4' from its neutral position, the conduit 18 is connected to the -supply.conduit 23, and a lowering of the valve member from its neutral position results in a connection of the conduit 18 to the discharge conduit.

The lever 22 is operatively connected at its opposite ends by any suitable. means 26 and 27 to motors M1 and M2 which operate to move the lever and position the valve member 21'. The motor M1 is energized by an amplifier andmotor control device 28, which is connected into. a. bridge circuit generally designated'.29. windings 31 and 32 are. connected into the. bridge circuit and are energized varying amounts depending, upon the position of a core piece 33 in a magnetic field produced by the energizing of a Winding '34 from any suitable source of electrical power. Any change in the energizas tion of the windings 31 and 32 produces .anJunbaIance in: the. bridge circuit. and effects an. operation of the motor M1. A contact arm 36 isv operatively connected to the motor bysuitable means 37 so that it is moved by the motor along a slide-wire resistance 38 in a direction to effect a rebalancing of the bridge circuit. The core piece 33 .is connected. to a diaphragm 40 which has its opposite sides connected through. pipes 41 and 42 to different points inthe air stream through the furnace. The points in. the air stream. are selected so as to subjectfthe opposite sides of .the diaphragm to pressure differences Whichare adequate to move the-core piece. 33 as the flow of air changes. The. connection between the motor M1 and thelever. 22 is. such that. an operation of the motor resulting from an increase in the rate of airflow through the furnace produces a positioning of the valve member 21 to supply fluid from the conduit 23 through the conduit 18 to'the diaphragm 19 for moving the valve. 12 toward its closed position. It will be seen that a reduction in the. flow of oil. past the valve 12 to the returnv line 14 will result in a flow of. a larger portion of the oil from the burner to the furnace.

It is desired that the change in the flow of oil from the burner to the furnace be in proportion to the change in the flow of air through the furnace. To obtain this it is necessary'that some means he provided for moving the valve member 21. to its neutral position as soon as the valve 12 has been adjusted to produce the proper flow of oil to the furnace, otherwise the flow of fluid relative to the diaphragm 19 will continue until the valve 12 is either closed or moved to its full open position. To move the valve member 21 to its neutral position when the desired'ilow is reached, there is provided a c'ncuit', generally designated 45, which is connected to the metersfS .and 5A and energizesv the motor M2 to cause its operation in one direction or the other as the difference in flow through the meters increases or decreases.

The meters 5 and 5A are alike, and, vasshown in Fig. v1', include a casing 48' having intake and discharge ports 49 and 50 separated by a partition 51. A cylindrical member 52 carried by the partition has its interior connected by ports 53 and slots 54 to the intake and dis charge ports", respectively; A plunger 55 has aportion 56 engageable with the upper end of the member. 52, anda portion. 57 extending into the-member so thatsitiis. acted vuponby thefluid flowing into; the latter from the intake port. A core piece 59 is carried by the plunger 55 and is positionable by the latter relative to windings 60, 61 and 62. The plunger is moved upwardly against the action of a spring 63 in proportion to the flow of fluid through the casing. I

The circuit 45, shown more fully in Fig. 3, comprises the windings 60, 61 and 62 of the meter connected with the windings 60A, 61A and 62A of the meter 5A in a bridge circuit in such a way as to unbalance the circuit in proportion to changes in the difference of the flow through the meters. When the circuit is unbalanced, the motor M2 rotates in one direction or the other and operates through suitable connections 65 to move a contact arm 66 along a slide-wire resistance 67 and effect a rebalancing of the bridge circuit. The motor M2 is also connected by suitable means 68 to a recording arm 69 of a meter 70 for positioning the arm to record the differences in the flow through the meters 5 and 5A. The connections 27 between the motor M2 and the lever 22 are such that the valve member 21 is moved to its neutral position when the circuit 45 becomes balanced. The general circuit of Fig. 3 is fully disclosed in the Hornfeck Patent 2,406,221, and further description of the sameherein is not deemed necessary. 6

' It will be seen that with the system so far described the fuel oil will be supplied by the pump 6 at a constant rate to the burner 1 where a part'of the oil will pass through the opening 8 to the furnace to be burned, and the remainder will escape past the valve 12 to the return line 14. The electrical control circuit will operate in response to the flow of air through the furnace and to the difference in flow through the meters 5 and 5A for positioning the valve 12 to effect the desired distribution of oil from the burner to the furnace and the return line. It will be appreciated that the difference in flow through the meters 5 and 5A is the amount of oil that is consumed by the furnace, and that the meter arm 69 records this amount; 6 If the flame should go out in the furnace for some reason, or if it should be desired that the flame be extinguished because of high steam pressure, high superheat temperature, low rate of superheat steam flow, high furnace circuit temperature, low inert water pressure or failure of auxiliaries, such as water pumps, etc., then it is necessary that the flow of oil to the burner but cut off. To accomplish this we have provided a conduit 72 for conducting fluid from a source of supply to a diaphragm 73 which is operatively connected to the valve 3. A valve 74 controls the flow of fluid through the conduit 72 and is adapted to be moved to its open position on the energizing of a solenoid winding 75. The winding 75 is connected into a suitable circuit which is energized when any of the conditions which it is desired to protect against exist.

On the supply of fluid to the diaphragm '73, the valve 3 is positioned to cut off the flow of oil to the burner and to direct the flow to a conduit 76 communicating past a check valve 77 with the return line between the check valve and the valve'12. If all of the oil discharged by the pump was conducted through this conduit to the return line, the flow through the meters 5 and 5A would be the same and the valve 12 would be wide open. However, the flow of air through the furnace when it is shut down would be greatly reduced but would still be of a substantial amount. As the control system for the valve 12 operates, as explained above, to produce a difference in flow through the meters 5 and 5A proportional to the air flow through the furnace, the valve 12 moves toward its closed position in an attempt to produce a flow difference through the meters proportional to the substantial flow of air in the furnace. The closing of the valve would, of course, produce no difference in flow between the two devices since there would be no burner through which the oil could discharge. The valve 12, under these conditions, would close completely and cut off all flow of oil from the pump to the system. When the emergency conditions ceased to exist, the valve 3 would operate to supply full volume of oil to the burner initially and, since the valve 12 would not immediately open to pass some of the oil to the return line, an undesirable excess quantity of oil would be discharged to the furnace.

In order that the valve 12 may be positioned to maintain a difference in the flow through the meters 5 and 5A proportional to the air flow in the furnace when the supply of oil to the burner is cut off, we have provided lit a conduit 80 containing a flow resistor 81 and connected from the conduit 76 to the return line 14 across the meter 5A, the valve 12 and the check valve 77. The conduit 80 and the resistor 81 are adjusted to offer a resistance to the flow of oil equal to the resistance offered to the flow from the burner through the port 8. It will be seen that the by-pass makes it possible to obtain a difference in flow through the meters 5 and 5A proportional to the air flow through the furnace when the valve 3 operates to cut off the flow to the burner and to direct all of the flow to the conduit 76. The difference is approximately the same as it should be if the flow was suddenly switched to the burner. The valve 12 is in such a position that it WOIllCl pass a large portion of the oil from the burner to the return line, and the smaller portion of the oil passed to the furnace would be insuflicient to flood the latter during its period of starting.

In order that a record may be had showing the actual amount of oil burned in the furnace, there is provided with the meter 70 a recording arm 83 connected to a plunger which is actuated by a solenoid winding connected in parallel with the winding 75. When fuel is burning in the furnace, the arm 83 makes a circular path near the outer edge of the chart, and, when the furnace is shut down, the arm is swung a slight amount to make a circular path of different radius. The oil flow recorded by the arm 69 during the period when the arm 83 indicated that the furnace was operating, would show the total amount of oil consumed in the furnace.

The control system shown may be used for regulating flow to a plurality of burners simultaneously, and, to indicate the connection of other burners in the system, we have shown conduits 87 and 88 connected to the system at the supply and discharge sides of the burner 1 for conducting fuel relative to the supply and discharge of another burner, not shown.

While there is specifically described in this application one form which our invention may assume in practice, it will be understood that this form is shown for purposes of illustration and that our invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What weclaim as new, and desire to secure by Letters Patent of the United States, is:

'1. A burner system for a furnace comprising, in combination, a burner, a pump for discharging a constant volume of fuel, means normally operative to deliver all of the fuel from said pump to said burner, a return line for conducting a portion of the fuel away from said burner, flow responsive means connected to said delivery means and said return line, means for regulating the flow through said return line, means responsive to the changes in the rate of air flow through said furnace and to said flow responsive means for controlling said regulating means, and means for by-passing fuel around said burner when abnormal conditions exist in the furnace, said by-pass means including parallel conduits connecting said delivery means to said return line at opposite sides of said flow responsive means connected therein, one of said parallel conduits offering a resistance to the flow of fuel equal to the resistance of fuel flow from said burner to the furnace.

2. An oil burner systemin combination, an oil burner, pressure means supplying oil under pressure to said burner, a return conduit from the burner, a regulator in said return conduit regulating the discharge rate of oil from the burner, by-passing means for the burner, means actuating said by-pass means, said by-pass means including two lines each connected to said return conduit at different points along the return conduit, one of said lines having a fixed resistance to flow, and a flow responsive device in said return conduit located between said line connections to said return conduit, whereby the fixed resistance in one of said lines allows for the passage of oil in the other of said lines through the flow responsive device at the same rate when the burner is by-passed as when the burner is operating.

3. A burner system for a furnace including in combination, a burner, a pump for discharging a constant volume of fuel, means normally operative to deliver all of the fuel of said pump through said burner, a return line for conducting a portion of the fuel away from said burner, means for regulating the flow through the said return line, means responsive to the flow of air through the furnace and to the'difference in flow between said fuel delivery means and said return line for controlling said regulating means, means operative automatically to by-pass fuel around said burner when abrnrmal conditions exist in the furnace, said by-pass means including two lines connected with said return line with one of said lines offering a resistance to the flow of fuel equal to the resistance in flow of fuel through a burner tip, and said regulating means in the return line located between said two lines.

4. An oil burner system in combination, an oil burner, pressure means supplying oil under pressure to said burner, a fluid responsive device to the rate of flow of oil to the burner, a return conduit from the burner, a fluid pressure responsive valve in said return conduit regulating the discharge of oil from the burner, a fluid responsive device in said return conduit sensitive to the rate of flow of the oil return from the burner, means adapted to bypass the burners with the same rate of oil flow, and parallel paths to which the by-pass connects, one of said paths including the return meter, the other of said paths having a fixed resistance flow and connected to opposite sides of the return meter, the fixed resistance of such value that the return meter registers approximately the same when the burner is by-passed as when it is operating, whereby the amount of fuel fluid available to the burner is continuously in phase with the burner fluid demand.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,862,690 MacRae et al. June 14, 1932 2,165,182 Luhrs July 4, 1939 2,177,823 Donaldson Oct. 31, 1939 2,265,961 Ziebolz Dec. 9, 1941 2,334,679 Mason et al Nov. 16, 1943

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