US1756823A - Heat regulator - Google Patents

Description

F. E. HARRIS HEAT REGULATOR April 29, 1930.

Filed NOV. 16, 1922 2 Sheets-Sheet 1 F. E. HARRIS HEAT REGULATOR April 29, 1930.

Filed Nov. 16, 1922 2 Sheets-Sheet 2 AAAAAAAM awventoz GAL/441014167256 Tu k/10:00PM

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Patented Apr. 29, 1930 PATENT OFFICE FLOYD E. HARRIS, QF FLINT, MICHIGAN HEAT REGULATOR Application filed November 16, 1922. Serial No. 601,426.

Another object of the invention is the provision of new and improved thermally controlled means for automatically regulating the supply of air and fuel to a fluid or liquid fuel burner.

A still further object of the invention is the provision of a new and improved valve for controlling the supply of air and fuel.

Other and further objects and advantages of the invention will appear from the description and accompanying drawings, in which,

Fig. 1 is a diagrammatic View of the device as applied to a commercial oil burner.

Fig. 2 is a sectional view of a valve mechanism with parts broken away.

Fig. 3 is a side elevation of the valve operating mechanism with parts broken away, looking in the direction of the arrow 3 in the Fig. 2.

Fig. 4 is a section on line 44=, Fig. 2; Fig. 5 is a diagrammatic view of a modified form of the device.

Fig. 6 is a view similar to Fig. 3 but showing a modified form of the device; and,

Fig. 7 is a section on line 77 of Fig. 6. Figure 8 is a diagrammatic View showing 35 the operating mechanism of the temperature control.

Onthe drawing the reference numeral 10 indicates a heat treating furnace of any well known construction having the opening 11 in the wall thereof, through which fuel is delivered to the furnace by means of a burner 12, of any suitable construction. The air and fuel are delivered to the burner through separate conduits as is common in the art, the air being delivered through a conduit as the pipe 13 and the liquid fuel through a separate conduit as the delivery pipe 14. The pipes or conduits 13 and 14 are provided with the usual hand operated valves 15 and 16. for 30 manually adjusting the supply of oil and air automatically regulating the supply of air and fuel to the burner for maintaining the furnace at a predetermined temperature. In order to do this, it is not only necessary to control the supply of air and fuel but it is also necessary to properly regulate the supply of each so that the two will form a proper combustible mixture at all points within the range of the controlling mechanism.

In order that the controls for both the air and the. fuel shall operate simultaneously it is desirable that both controls be positively operated by the same mechanism. Any suitable means may be employed for this purpose. One form of device for accomplishing this function is illustrated on the accompanying drawings in which the valve for controlling the air is rigidly mounted on and operated by the fuel valve stem. As shown on the drawing, a valve housing 18, provided with screw threaded ends 19 and 20 for connecting adjacent ends of the pipe 13, is provided with a restricted portion having transversely extending therethrough a cylindrical opening 24 in which is adapted to be rotat ably mounted a cylindrical air valve, as will presently appear. The inwardly extending ledges 21 and 22 form a port 23 leading into the cylindrical opening 24. A cover 25 is attached to the housing by suitable fastening means 25*, which is adapted to close one end of the cylindrical opening 24. The cover 25- is provided with an axial bore 26, to form a recess or compartment 27 that is closed by I the cap 28, secured in a counterbore in the outer end of the cover 25. The cap 28 is provided with a screw threaded opening in which is secured the inner end of the fuel supply pipe or conduit 14 The cap 28 is also provided with a valve seat 29 for a purpose that will presently appear. The side of the cap 25 is provided with an opening 30 extending into the recess or compartment 27. The

o ening 30 is counterbored to receive the end 0 the fuel delivery pipe 14.

Rotatably mounted in the cylindrical opening 24 is a cylinder or valve member 31 having the reduced portion 32 extending axially therefrom. The valve member 31 is in the form of a drum and has on one side thereof an opening 33. The opposite side of the member 31 is also provided with an opemng 35 which may be in the form of a rectangle or any other suitable form.

Since the amount of air that will flow' through a given orifice in a givenintervalof time depends on the difference 1n pressure on both sides of the orifice, it follows, that as the valve 31 reaches its maximum opening the differential pressure becomes less and less and consequently the valve opening must be correspondingly increased to compensate for the decrease in differential pressure. In order that the supply of air may increase uniformly throughout the range of movement of the valve in which there is'a substantial feed of air oras the differential pressure decreases the opening 33 must be so constructed that it increases in area in an increasing ratio as the valve is moved. As shown, the opening is in I the form of a trapezoid whereby an increas- 'ingly larger area of the opening of the valve will be caused to register with the port 23 for each increment of movement of the valve as it is rotatedto uncover said port. The reduced portion" 32 of the valve member 31 is provided with an axial bore in which is mounted the shaft 36. The inner portion of the shaft 36 extends axially through the drum 31 and its inner end is screw threaded as at 37 for engaging corresponding screw threads in the axial opening in the cover 25. The inner end of the shaft 36 is provided with a conical valve 38, which is adapted to engage the valve seat 29 in-the cap 28 of the cover 25, for regulating the supply of fuel to the fuel delivery pipe 14. The drum 31 is adjustably mounted on the shaft 36, in any suitable manner as by means of the set screw 39. The parts are so adjusted, that when the shaft 36 is turned to unseat the valve 38, the opening 33 will register with the port 23 whereby liquid fuel may pass through the fuel supply pipe 14*, to the delivery pipe 14 and at the same time s'uflicient air to form the proper combustible mixture,

. adjustably secured to the reduced portion 32 in any suitable manner, as by means of the cores 50 of said magnets. may be integral with or rigidly attached to set screw 44. The armature 43 is operated by means of a plurality of electro- magnets 45, 46 and 47, which are arranged in pairs and for convenience in description the members of each pair are designated by the same reference character. These magnets are secured within a housing 48, in any suitable manner as by means of screws 49, which engage the The housing 48 the valve housing 18. The armature 43 may be provided with an extension having a handle 51 thereon for manually operating the. valves. Stops 52 and 53 are provided for limiting the movement of said armatureineither direction.

The magnets 45, 46 and 47, are energized for operating the armature and thereby opening and closing the valves 31 and 38 by any suitable thermally controlled mechanism. One

form of control for accomplishing this purpose is shown diagrammatically in Fig. 1 of the drawing in which a relay system is employed. As shown, the reference numeral 54 indicates a contactswitch of a commercial pyromieter or potentiometer recording machine having two electrical contact members 55 and 56, which are-adapted to be engaged by the pointer or arm 57'. In Figure 8, I have shown the operating mechanism for the contact switch 54. This echanism comprises a thermocouple exposed to the temperature adjacent the burner, and controlling the galvanometer in the usual manner. The galvanometer, in turn, controls the mechanism for 1 13 operating the contact disc 54. Since the defiection of the'galvanometer is proportional to the temperature in the thermocouple, and

. the rotation of the disc is in proportion to the deflect-ion of the galvanometer, the disc when 1G5 properly calibrated, will indicate the temperature at the burner. I have made use of the discto control the ciicuit of the furnace control mechanism as will be later describedin detail. However, any preferred form of thermally controlled device such as a thermostat or the like, may be'used in place of the therm'o-couple if found to be desirable under particular operating conditions.

The relay system comprises a plurality of solenoids 58, 59 and 60, there being as many solenoids as there are pairs of electro-magnets. The solenoids are provided with cores or plungers 61, 62 and 63. In Figure 1 the electrical connections are shown with solenoid 6O energized. The plungers are adapted to open and close electric switches for energizing the elect-ro- magnets 45, 46 and 47. In order to accomplish this, the plungers are provided with extensions on which are mounted switch operating members 64, 65

and 66, which are adapted to engage the switchlevers 67, 68, 69, 70 and 71, for closing the various switches. The switch levers 67,

68, 69,70 and 71 are each pivoted as at 72, and

are held in open position by any suitable means such as the springs 73. Dash pots 74 may be provided for retarding the movement of the plungers 61, 62 and 63. The two electric leads .7 5, 76 supply current to the solenoids for operating the plungers thereof.

' One member of the switch 67 is connected to the lead 75 and to the arm 57. The lead 76 is connected to one end of each of the solenoid windings. The free end of the wire of the solenoid 58 is connected by means of the con-' ductor 77 to the contact member 55'on the switch 54. The free end of the winding of the solenoid 59 is connected by means of the conductor 78 to one member of switch70; while the free end of the winding of the solenoid 60 is connected by means of the conductor 79 to the contact member 56, of said contact switch 54.

The current for operating the electro- magnets 45, 46 and 47, is supplied by the conductors 80 and8l. One end of the windings of each of tlie-electro-magnets is connected to the conductor 82 which is in electrical contact with the lead 81. The free end of the windings of the magnets 45, is connected by means of conductors 83 and 84 with one member of the switch 71. The free end of the windings for magnets 46 are connected by means of conductors 85 and 86 to one member of the switch 69; while the free end of the windings of the magnets 47 is connected by means of conductors 87, to one member of-the switch 68.

-When the parts are being moved to the position shown in Figs. 1 and 2, of the drawing the current may be traced as follows The current has entered through the lead 75 and passed along the conductor 88, through the arm 57, the contact 56, the conductor 79, and

through the solenoid 60, energizing the same 'and elevating the plunger 63, causing the operating member 66 to close the switch 71. The current will pass from the solenoid back to the lead 76. As the plunger 63 is drawn upward by the solenoid the member 66 will release the lever arm ofthe switch thus permitting the spring 73 to open said switch. The member 66 will engage the end of the lever of the switch 71 with a wiping contact thus closing the switch for a brief interval of time. In Figure 1 the connections are shown in the positions assumed after the above-described movements.

When'the switch 71 is closed, a current will enter through the lead 81 and passing through the electro-magnets 45, will energize the same and cause the armature 43 to rotate the valve 31 to close .the same. From the electro-mag nets 45 the current will pass through the conductors 83 and 84, through the switch 71 back to the lead 80.

The electro-magnets 47 are energized in a similar manner, by the operation of the solenoid 58 for opening the valve to its full extent. The electro-magnets 46 for opening the valve to its intermediate position are energized in a manner that will now be described.

Assuming that no current is passing through the leads and 76 all the plungers will be at their lower limit of travel and the members 64 and 66 will engage the levers of the switches 67' and 70, thus closing those two switches at that point. Assume also that the arm 57 is at the neutral point 90, between the contact members 55 and 56. If the current now be turned on, it will pass along the lead 75 through the switch 67, along the conductor '91, through the switch 7 O, the conductor 78, and through the solenoid 59 thus energizing the same and elevating the plunger 62. From the solenoid the current passes back through the lead 7 6. As the plunger 62 is elevated the contact member 65 engages the lever of the switch 69 and closes said switch. When said switch is closed the current entering through now be described in connection with a batch type furnace although the regulator is equally useful when applied to furnaces of the continuous type, the operation being substantially the same except for the initial stages. WVhen the furnace is freshly charged with material to be treated its temperature is greatly lowered. .This results in the pyrometer controlled contact switch 54 moving to a position where arm 57 engages contact 55 bringing 6 into operation solenoid 58 and electromagnets 47 which swing the valves to full open position. The furnace is now fed fuel and air at the maximum rate and the temperature rises. When the temperature reaches a predetermined point, for example 1700 F the pyrometer mechanism has rotated the contact switch 54 so that arm 57 engages the neutral point 90 on the switch. This results in the energization ofsolenoid 59 and magnets 46 throwing the valves to mid position. Now in actual practice the temperature in the furnace is not stable but fluctuates frequently and quickly, so that-at this point in the operation the contact switch 54 swings back and forth at intervals causing the valves to swing back'and forth between full open and mid position. This continues until the furnace temperature rises to a point, depending on the setting of the -pyrometer, at which the valves begin to operate between mid position and off position, the valves being moved to the latter position when the arm 57 engages contact 56 on the contact switch 54, energizing solenoid 60 and magnets 45. The operation between mid position and off position continues until the temperature of the fur- 5 nace reaches a predetermined maximum, say about 1710. After the furnace has thus come up to the maximum temperature for which the pyrometer was set, the valves will continue to fluctuate between mid position and off position holding the furnace at that temperature. If it is desired to operate the furnace at a higher or lower temperature than that taken as an example it is merely necessary to adjust the pyrometer controlled contact member 54. I I

The above: mechanism thus provides an effective control of furnace temperature throughout the working range and the temperature is also prevented from rising above a certain maximum whether the furnace is working or idle, the arrangement being such that a minimum of fuel is used under the lattcr condition. The system also possesses great flexibility in that the fluctuation of the 13 valves between zero and mid position permits almost any maximum temperature desired. The mechanism also preferably has incorporated in it, as previously described, the special valve arrangement which provides a 3; correct proportioning of fuel I and air throughout the feeding range of the valves. In Figs. 5, 6 and 7, is shown a modified form of the device in which the electro-mag nets for rotating the valves are provided with sscircuit breakers whereby the armature Will automatically open the circuit when it moves to its adjusted position, opposite the energizing magnet. In this form of the device, only two solenoids 95 and 96 need be em- 40 ploycd. The pivoted switch arm 97 is provided with an armature 98 whereby when the solenoid 96 is energized the arm is moved to engage the contact member 71*, and when the solenoid 95 is energized the arm will engage the contact member 67 The solenoids 96 and 95 are energized when the arm 57 engages the contacts and 56, respectively. I/Vhen the arm 57 engages the neutral point on the contact switch 54 and the solenoids 95 50 and 96 are de-energized, the arm 97 will be caused to engage the contact member 69 by any suitable means such as the light springs 99 and 100.

, With the contact switch in the positionv shown in Fig. 5 of the drawing, the current entering the lead 75 will energize the solenoid 96 and return through the lead 7 6. The

energized solenoid 96 will cause the armature 98 on the switch arm 97 to engage the contact 71 and, complete the circuit from the lead 80, through the electro-magnets 45 along the conductor 82 to the lead 81*. I The energized electro-magnets 45 will cause the armature 43 to rotate the valve shaft 36 and opposite the energized magnets, the extension 101 will engage the inner endof the pivoted lever 102 and thereby open the circuit through said magnets. Each set of electro-magnets is provided in a similar manner with circuit breakers 102 which operate in the same manner as has just been described.

The regulator herein disclosed has been shown applied to a heat treating furnace but it is to be understood that it is not limited to that use but may find application wherever it is desired to control temperatures produced by combustion. Furthermore, certain of the features of the invention are capable of broad application apart from their use in a heat regulator; thus the arrangement of valves which affords correct proportioning of fuel and air throughout the range of adjustment thereof may be used wherever it is desired to secure correct combustion not only in furnaces but in heat engines and the like; the multiple valve operating device may be used in connection with other than fuel feeding apparatus; and so on. It is the intention of applicant to claim the parts as well as the whole of this or anization broadly as well as specifically.

t is thought from the foregoing taken in connection with the accompanying drawings that the construction and operation of my device will be apparent to those skilled in the art, and that various changes in size, shape, proportion and details of construction may be made without departing from the spirit and I scope of the appended claims. \I

What I claim is 1. In combination, a heat treating furnace, a burner for supplying fuel to said furnace, a conduit for supplying fuel to said burner, a conduit for supplying air to said burner, a valve shaft, valves on said shaft for controlling the supply of air and fuel to said burner, and means for preventing the temperature of said-furnace from rising above a predetermined point, said means including mechanism for operating said valves and thermally controlled. means for operating said mechanism.

2. In a device of the class described, a burner, a plurality of conduits for su plying said burner with combustible fluid, a valve shaft, a valvein each conduit mounted on said shaft, an armature on said shaft and electro 'magnets and controlled b conduits for-supplying a combustible fluid to said burner, a valve shaft, a valve in each conr closing said valves, a relay mechanism for energizing said armatures, said relay mechanism including a solenoid for each pair of magnets and thermally controlled means for automatically energizing said solenoids.

5. In a device of the class described, a burner, a plurality of conduits for supplying a,c0mbustible fluid to said burner, a valve shaft, a cylindrical valve rotatably mounted in one of said conduits and secured to said shaft, a valve seat in the other of said conduits, a housing for said valve seat, a screw threaded o ening through one side of said housing, sa1d valve shaft being screw threaded into said opening and a valve on the inner end of said shaft for engaging said valve seat, and means for rotating said shaft.

6. In a fuel control device of the class described, a valve housing having a cylindrical opening extending transversely therethrough and an opening at right angles to said cylindrical opening, a control housing extending laterally from said valve housing, a closure for one end of said cylindrical opening, said closure being provided with a valve seat and with a screw threaded opening in alinement with said valve seat, a cylindrical valve having an irregular opening rotatably mounted in said cylindrical opening, a shaft" extending axially of said 0 lindrical valve, means for securing said cyl shaft, the inner end of said shaft being screw threaded for engaging screw threaded opening in said closure, a valve rigidly secured to the inner end of said shaft for engagin said valve seat, an armature on the outer on of said shaft, a plurality of pairs of electromagnets mounted in said housing, means for automatically energizin said electro-magnets and a handle on sai shaft for operating the same.

7. In a device of the class described, a fluid conduit, 9. fuel conduit, a burner common to said condu1ts, a valve for sald flu1d conduit,

a valve for said fuel conduit, electrical means responsive to. temperature chan es at the burner, electro-magnets for eifectmg ad'ustment ofsaid valves and relays inter ose between said electrical means and sai electrosaid electrical means for energizing said e ectro-magnets.

lndrical valve to said,

8. The combination of a burner, a conduit for conducting an element of combustion to the burner, a valve in said conduit, said valve having a-substantially closed position and a plurality of open positions, and normally occupying one of said positions, and thermal- 1y controlled electromagnetic means for moving said valve toany of said other positions, a conduit for conducting a second element of combustion to the burner, a valve in said conduit, and means for actuating said secondnamed valve along with the first named valve to maintain proper proportions of the elements of combustion.

9. In the con'ibination as defined in claim 8 said valves being mounted on a common shaft.

10. The combination of a burner, a conduit for conducting'fuel to the burner, a' conduit for conducting air to the burner, valves in said conduits, and quick acting temperature controlled means for varying the de ree of opening of said valves, said last name means embodying elcctro-responsive devices acting directly on the valves for imparting step by step movement to the valves.

'11. In a furnace control the combination of a burner, a conduit for supplying an element of combustion-to the burner, a valve for said conduit having a closed position and a plurality of open positions, and a plurality of electromagnets each adapted to move the valve-to a different one of said positions, a conduit for supplying a second element of combustion to said burner, a valve in said conduit having a closed position and a plurality of open positions, said valve being arranged to be operated by said electro-magnets in synchronism with the first-named valve.

12. In a furnace control the combination of a seat of combustion, means for supplying an element of combustion thereto including control devices having a closed position and a plurality of open "positions, and means solely responsive to temperature changes at the seat of combustion for causing said control devices to fluctuate between closed position and one of said open positions, or between the two open positions to effectively control the temperature of the burner, and means for supplying another element of combustion to said seat of combustion, said last named means being controlled by said first named supply ingmeans to maintain proper roportions of the elements of combustion t roughout the range of adjustment.

In testimony whereof I affix my signature.

FLOYD E. HARRIS.

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