US2286630A - Heating apparatus - Google Patents

Description

June 16, 1942- w. s. LANDON ETAL HEATING APPARATUS Filed Feb. 23, 1940 as I l NvENToRs W m ATTORNEY Patented June 16, 1942 I UNITED STATES PATENT OFFICE HEATING APPARATUS Walter S. Landon and Philip S. Russel, Detroit, Micln, assignors to Detroit Lubricator Company, Detroit, Mich-., a corporation of Michigan Application February 23, 1940, Serial No. 320,322

14 Claims. (01. 236-1) This invention relates generally to new and with aaminimum flow stop memberl adjustably useful improvements in heating apparatus and carried by a bracket II of the casing I overlying more particularly to means for controlling the the aperture I.v Upward or valve opening movec-peration of a liquid fuel burner. ment of the valve member 4 is limited by engage- One object is to provide an apparatus in which m'ent of the flange 9 with a maximum flow stop a reduction in the supply of oil to the burner premember I2 adjustably carried by the bracket l I. cedes a reduction in the supply of combustion The extreme upper end portion of the stem porsupporting air. tion 6 is guided within a hollow boss' I3 of the Another object is to provide a novel temperabracket II.

ture responsive means for controlling the opera: m A hook-shaped bimetallic power element I4 has tion of a liquid fuel burner. an end portion l5 at the terminus of 'the curved Another object is to provide auxiliary autopart I6 and has a straight or lip part I8 having matic controlling means for an automatically opan end portion II. The element I4 is preferably erated control device. secured at its end portion I5 to a bracket I9 rigid Another object is to provide an apparatus havwith the casing I and so positioned that the end ing an operating means normally controlled by portion I! is operable to engage the underfaceof a first actuating means and having a second acthe flange 9 so that upon-upward movement of tuating means for moving the operating means the lip or straight part I8, the valve member 4 irrespective of the operation of 'the first actuatwill be raised to permit flow of fluid through the ing means. 2o outlet port 3. An electrical heater element is Another object is to provide an apparatus havpositioned within the element curved part I6 and ing an operating means moved to one position by po energization acts tOheat the P is Which an actuating means and moved to a second posiopens up, thereby moving the lip part I8 uption by a second actuating means. ward to engage the flange 9 and to lift the valve The invention consists in the improved conmember 4 against the t p member struction and combination of parts, to be more S c bimetallic D element Similar fully described hereinafter and the novelty of to the element I4, has a lip part 23 and a curved which will be particularly pointed out and disp t terminating in endportions tinctly claimed. spectively, and is rigidly secured to a supporting In the accompanying drawing, to be taken as em e 21 at the portion 26. The member 21 is a part of this specification, we have fully and secured to the casing I in a manner similar to clearly illustrated our invention, in which drawat Of the element The P 24 e eives an ing electrical heater 28 which acts upon'energization Figure 1 is a schematic view of the apparatus o se the p rt 24 o Op n a e p part 23 embodied in a liquid fuel hot water heating appato move upw d. p d ent causes the ratus, and part 23 to engage a downwardly extending pro Fig. 2 is a view of a modification of a portion tuberance 29 of a mercury tube switch holder 30 of the apparatus showing a new and improved pivoted, as at 3I, so that a mercury tube switch heat motor. 32 carried thereby will be rotated to circuit closed Referring to the drawing by characters, the nuposition- The Switch 32 is biased toward pen meral I designates generally the casing of a concircuit pos on and i gement with a stop stant liquid level device having a liquid receiving member P chamber 2 with an outlet valve port 3 which is An externally threaded, p-sh p d member adapted to be connected to a liquid fuel burner 5. is Sc e into n p e o h a (not shown). A valve member 4 has a conical side wall of the reservoir 36 which contains the portion 5 which cooperates with the port 3 to u d d y e uel burner (not shown). control flow of fluid therethrough, and has an e member 35 opensexternally of the reservoir upwardly extending stem portion 6 extending 36 and has an inner wall member 31 in good heat through and guided within an aperture I in the transfer relation with the reservoir fluid. A top chamber wall 8 of the chamber 2. The valve thermostatic element 40, similar to that described member 4 is biased toward closed position by a and disclosed in Letters Patent No. 2,128,274, helical coil spring 8 interposed between the wall granted to Sergius Vernet and dated August 30, 8 and an annular flange 8 of the member 4. 1938, comprises a cup-shaped bottom casing Movement in the valve closing direction, howmember 4I having secured to its open end 9. ever, is limited by the engagement of a flange 9 flanged or flared portion 42 of a tubular shapedupper casing member 43. A helical coil com-' pression spring 44 is positioned within the member 35 concentric with the tubular member 43, and has one end abutting an externally threaded annular member 45 which also surrounds and is concentric with the tubular member 43. The otherend of the spring 44 abuts the flange 42 and as the member 45 is screw-threadedly secured within the open end portion of the member 35, the spring 44 acts to hold the bottom wall of the cup-shaped member 35 against the wall member 31 and in good heat conductivity therewith. This particular construction also permits the element 46 to be held against the wall member 31 with a predetermined force irrespective, between certaln limits, of the exact positioning of the member 45 with respect to the member 35. In this manner production tolerances may be increased to lower costs.

The temperature sensitive material, which is in this instance a material which undergoes a change in crystalline structure, thereby increasing in volume upon increase in temperature, is carried within the cup-shaped portion adjacent the bottom wall thereof, and the space overlying the sensitive material and underlying a diaphragm 46 is filled with a liquid which may bea concentrated solution of sodium silicate, and which acts to transfer the force exerted by the sensitive material to the diaphragm 46. This type'of sensitive element is substantially non-responsive to temperature changes below a predetermined temperature, and then upon attainment of this predetermined temperature acts within a very narrow range of increasedtemperature to expand and do its work. A thrust rod 41 extends longitudinally through the tubular member 43 and has a flanged end wall 48 which is held. against the outer side of the diaphragm 46 by a helical coil compression spring 49. The spring 49 is concentric with the' thrust rod 41, and is interposed between an internal flanged portion of the tubular member 43 and the flange end wall 48.

A lever member 56 is fulcrumed, as at 5|, on a rigid support 52 carried by the tubular-member switch 59 is rotated to closed position upon upward movement of the rod 54. However, when the temperature of the fluid within the fluid containing reservoir 36 is at or above a predetermined temperature, the rod 54 is in its down position and the thermostatic element is against a stop member or pin 63 in the position shown in Fig. 1 with the switch 59 in open position. Element 40 will move and/or hold valve member 4 against the minimum stop l6 irrespective of the operation of the element l4. Upon cooling of the fluid in reservoir 36, the element 48 will-cool and move the rod 54 upward and through pin 63 move the switch 59 again to closed circuit position and place valve member 4 under the control of the element l4.

A switch 64, which may be a manually operable switch, as shown, or an automatically operable switch, such as a temperature sensitive switch responsive, for example, to room temperature, all

vof which are well known in the art, is supplied with electrical energy from a source of supply (not shown). A lead wire 65 connects one side of the mercury tube switches 32 and 59 with the switch 64, and a lead wire 66 connects the other side of the switch 59 with one side of the heater element 20. The other side of the heater element 26 is connected by a lead wire 61 to one side of the heater 28 and lead wire 68 connects the other side of the' electrical heater 28 to the switch 64 so that upon closure of the switches 59 and 64, current will flow through lead wires 65, 66 to the heater element 26 and electrical heater 28 and back through the switch 64 to the source of energy. Current flowing through the elements 20 and 28 acts to heat the bimetal parts I6 and 24. Heating of part l6 moves the lip part |8 to raise the valve member 4 until flange 9 engages the stop'member I2 and against the force 43, and is pivoted to the thrust rod 41, as at 53,

sothat it may be rotated by the rod 41 in accordance with the expansion and contraction of the sensitive material. A connecting rod 54 has a lower end guided within the hollow boss l3 and is operable to abut the upper end of the valve member 4. An upper end portion 55 of the rod 54 is of reduced diameter, and is loosely received and guided within an aperture in the lever member and is movable relative thereto. A helical coil compression spring 56 is con-- centric with the rod 54 and is held under compression between the lever member 56 and a shoulder 51 formed at the intersection of the reduced portion with the normal diameter of the member 54 and acts to hold the lever member 50in engagement with a nut 58 screw-threadedly secured to the rod portion 55. The spring 51 further acts as a lost motion or over-travel connection so that the lever member 56 can have continued rotation subsequent to engagement of .the valve :memberflange 9 with the minimum stop member l0, thereby relieving the parts of any undue stress.

A mercury tube type switch 59 is carried within a holder 60 pivoted, as at 6|, and biased toward open position. A downwardly extending protuberance 62, of the holder 66 normally engages a pin 63 carried by the rod 54 so that the of a spring 8. The other side of the switch 32 is connected by a lead wire 69 to a motor 16, and by a lead wire 1| to lead wire 68, and through switch 64 to the source of supply. Heating of the part 24, due to energization of the element 28 by closure of the switches 59 and 64 causes the lip part 23 to engage the protuberance 29 and rotate the mercury tube switch 32 about its pivot 3| and into circuit making position. Electrical energy them flows from the switch 64, lead wire 65, switch 32, lead wire 69 to the motor 10 and back through lead wires 1| and 68 and switch 64 to the source of supply. The motor 16 in this instance is used to supply the' necessary air for combustion of the fuel being admitted to the burner through port 3, but, however, may be some other form of electrically controlled equipment for cooperation with the fuel supplied through the port 3. A fuse 12 is inserted in the lead wire 68 intermediate the connection of lead wires 68, H and the switch 64, and acts to rupture the electrical circuit to both the motor 16 and elements 28, 28, in the event that the current flowing through lead wire 68 becomes excessive. The motor 10 is thereby stopped and the valve member 4 is moved to minimum flow position, or until flange 9 is in engagement, with stop member ID.

Fig. 2 shows a modified form of the power elements I4, 22, and in which modification the elements 4, 22 have been fabricated from a single element 15 split longitudinally to form a pair of lip portions 16, 11 for actuating the valve member 4' and switch 32' respectively. The longitudinal split extends into the hook portion of the element 15 and terminates prior to but substantially at the point where the hook portion is secured to the supporting member l9 to form a pair of hook portions I8, 19. These portions 18, 19 are heated by the same heater element 20' and therefore any variation in the output of the heater element 20' will afiect the operation of both of the element lip portions 16, I1, and the relative time lag of operation between the two portions, 15, 11 will not be afiected. The con: struction, as shown, in Fig. 2 will also alleviae the dimculties caused by variation between dif- I ferentheating elements which may be encountered in manufacture and also prevents a replacement of one matched bimetallic element by one which has a different characeristic.

The operation of the apparatus is as follows: Upon closure of the switch 84, electrical current flows from the source of supply through lead wire 65, switch 59, lead wire 66 into the heater element 20, lead wire 61, element 28 and lead wire 68 back to the source of supply. Passage of current through the elements 20, 28 causes the elements to heat up and warm the bimetal ele-,

ments I4, 22 which act respectively to move the valve 4 to open position and the switch 32 to closed circuit position. The heater elements 20, 28 have been so chosen relative to each other and to the elements I4, 22 that the proper sequence of operation of the valve member 4 and the motor ID is accomplished. The burner operates to raise until a predetermined temperature of the fluid I in the reservoir 36 and of theelement 40 has been reached. Upon the attainment of the predetermined temperature the crystalline material within the member 4| starts to Change its physical state and expands forcing the diaphragm '46 outwardly. Outward movement of the diaphragm 46 acts through the thrust rod 41 to rotate the lever member 50 about its pivot 5| in a counterclockwise direction to move the rod 54 downward into engagement with the valve member 4. Continued movement of the diaphragm 46 moves the flange 9 of the valve member 4 into engagement'with the minimum stop member I0 and at the same time the pin 63 is moved downward allowing the switch 59 to rotate into circuit breaking position. Continued movement of the lever member 50, due to continued expansion of the crystalline material, acts to compress the spring 51 for lost motion between the parts so' that the parts are not unduly strained. Upon.

opening of the switch 59, the elements I4, 22 begin to cool and after a predetermined time, which in the case of a pot-type furnace, is sufficient to burn the remaining excess fuel, the element 22 will cool sufficiently to allow switch 32 to rotate to open circuit position, thereby to stop the motor 10. The element l4 upon cooling assumes a position disengaged from the flange 9 but no change in operation results because the valve member 4 is positively moved to minimum flow position against the valve opening force of element I4 by the stronger element 40.

It may be seen that the apparatus described is one which is operable to control a liquid fuel burner in a new and novel manner. The burner is supplied with fuel subsequent to the actuation of the heat actuated elements, which are so arranged that should one bimetallic heater ele ment become inoperative, the other bimetallic element heater would fail to function and thereby prevent an. improper burner operation. The apparatus is also so arranged that upon the attainment of a predetermined temperature condition of the fluid heated by the burner, the fuel flow is reduced to a predetermined minimum flow and at a subsequentpredetermined relative time the air supplying means is stopped. This apparatus also is constructed and arranged so that the fuel valve is not modulated throughout the temperature range of the heated fluid but acts substantially. at a single temperature to move the valve to closed position, thereby allowing for the maximum burner output and consequent rapid rise in temperature-of the heated fluid until the predetermined desired temperature is reached, after which time a very slight temperature increase rapidly moves the fuel valve to minimum fire position.

In Fig. 2 there is shown a new and improved bimetallic heat motor so constructed and arranged.

that it can actuate two means at a fixed relative relation therebetween irrespective of variation encountered in the actuating heat source and also will not act to operate a means without the subsequent actuation of the other means.

What we claim and desire to secureby Letters Patent of the United States is:

1. In an oil burner control, a fuel supplying valve means, an air supplying means, electrical means operable to, exert a force on said valve means, said electrical means being operable upon exertion of said force. to move said valve means.

means, means sensitive to the medium heated by said fuel and operable upon a predetermined temperature directly to move said valve means toward closed position and to deenergize said' electrical means for stopping of said air supply subsequent to the closing of said valve means, and means connecting said sensitive means and said valve means and having a lost. motion portion, said lost motion portion acting to allow said valve means to be controlled by said electrical means below said predetermined temperature independently of said sensitive means.

3. In an oil burner control, a fuel supplying valve means, an air supplying means, electrical means operable to move said valve means toward open position and to start said air supplying means, means sensitive to the medium heated by said fuel and operable upon a predetermined temperature directly to move said valve means toward closed position and to deenergize said electrical means for stopping of said air supply subsequent to the closing of, said valve means, means connecting said sensitive means and said valve means and having a lost motion portion, said lost motion portion acting to allow said valve means to be controlled by said electrical means below said predetermined temperature independently of said sensitive means, and means operable to allow continued movement of said sensitive means subsequent to the closing of said valve means.

4. In an oil burner control, a fuel supplying valve means, an air supplying means, electrical means operable to exert 'a force on said valve means thereby to move said valve means toward open position said electrical means also being operable to start said air supplying means, means sensitive to the medium heated by said fuel and operable upon a predetermined temperature directly to move said valve means toward closed position against said force of said electrical means and to deenergize said electrical means for stopping of said air supply subsequent to the closing of said valve means, stop means limiting movement of said valve means in said open direction, and stop means to limit movement of said valve means toward said closed position.

5. In an apparatus of the character described, a'first controlling means movable in two directions to control flow of fuel to a fuel burner, an

"electrical controlling means for supplying air 'means in one of said directions, a thermostatic power element sensitive to the output of the fuel burner and operable to move said first means in a second of said directions against the force of said heat motor means, said power element also being operable torender ineffective said heat motor means, a second heat motor means, and a switch means for controllingsaid electrical means and operable to be moved to one position by said second heat motor means, said second heat motor means being operable to be rendered ineffective by said power element to hold said switch means in said one position.

6. In an apparatus for use with a fuel burner having a fluid fuel fiow controlling valve, means for actuating the valve to regulate the flow of fuel to the burner, a thrust member operable to engage the valve, a temperature sensitive power element sensitive to the output of the burner, means interconnecting said power element and said thrust member, said power element being operable upon a predetermined high temperature to movesaid thrust member into engagement with and to move the valve to one position, and means moved by said power element and operable to render said actuating means ineffective.

'7. In an apparatus for use with a fluid fuel burner having a flow controlling means, means for actuating the controlling means, a thrust member positioned to operatively engage the flow controlling means, a temperature sensitive power element sensitive to the output of the burner, means interconnecting said power element and said thrust member, said power element being operable upon a predetermined high temperature to move said thrust member into operative engagement with and to move the controlling means to one position, means moved by said power element and operable to render said actuating means ineffective, and means limiting movement of said thrust member by said power element, said interconnecting means including a resilient means so that said power element can have continued movement subsequent to limitation of movement of said thrust member by said limiting means.

8. In an apparatus for use with a fluid fuel burner having a flow controlling means, means for actuating the controlling means, a thrust member positioned to operatively engage the flow controlling means, a housing, a temperature sensitive power element within said housing and sensitive to the output of the burner, a lever member fulcrumed to said housing and pivotally connected to said element, said thrust member having a pair of spaced abutments, said lever member being operable to engage one of said abutments, a spring member interposed between the other of said abutments and said lever member and operable to urge said lever member into engagement with said one abutment, said power element being operable upon a predetermined high temperature to move said thrust member into operative engagement with and to move the controlling means to one position, means moved by said power element and operableto render said actuating means ineffective, and means limiting movement of said thrust member by said power element, said spring member acting as a lost motion means so that said power element can have continued movement subsequent to limitation of movement of said thrust member by said limiting means.

9. In an oil burner control apparatus, a constant level chamber for supplying oil to the burner, a reciprocal valve supported in said chamber and operable to control the rate of supply of oil to the burner, a container for liquid to be heated by the burner, a temperature responsive control device secured to said container, a lever supported and movable by said device, means in said chamber and limiting the opening movement of said valve to determine the maximum rate of flow of oil, a thrust rod detachably secured at its opposite ends in engagement with said lever and said valve so that said said valve and said lever can have movement in unison, said thrust rod permitting said chamber to be freely removed from cooperative relation to said container and said control device, and means to adjust the effective length of said rod to provide for variation in the distance between said control device and said chamberand so that upon predetermined response of said control device said valve can be moved into engagement with said limiting means.

10. In an oil burner control apparatus, a constant level chamber for supplying oil to the burner, a reciprocal valve supported in said chamberand operable to controlthe rate of supply of oil to the burner, a container for liquid to be heated by the burner, a tegnperature responsive control device secured to said container, a lever supported and movable by said device, means in said chamber and limiting the opening movement of said valve to determine the maximum rate of flow of oil, a thrust'rod positioned between said lever and said valve, said valve having a stem in end abutting relation to one end of said rod, a sleeve member holding said stem and said rod in alignment, and an adjustable abutment on the other end of said rod and cooperable with said lever to transmit movement of said responsive means-to said rod, said adjustable abutment being operable to adjust the effective length of said rod to provide for variation in the distance between said control device and said chamber and so that upon predetermined response of said control device said valve can be moved into engagement with said limiting means, said thrust rod permitting said chamber to be freely removed from cooperative relation to said container and said control device. 11. In an apparatus for controlling an actuated means having two rates of output, a movable second means for moving said member in said one direction, and lost-motion means interconnecting said second moving means and said controlling means and providing unobstructed movement of said controlling means by said first moving means independently of said second moving means, said second moving means-being responsive to the output of the actuated means and operable to take up said lost-motion and to move positively said member in said one direction against the force exerted by said first moving means.

12. In a control apparatus, a first controlling means, a secondcontrolling means movable relative to said first means, a heat sensitive power means comprising a single element having two separate operating portions, each of said separate portions being operable to exert a force, one of said separate portions being operable to actuate said first controlling means, the other of said separate portions being operable to actuate said second controlling means, a power element operable to move said first controlling means relative to said second controlling means and against the force exerted by saidone separate portion, and means operable upon movement of said first controlling means by said power element to render said power means ineffective to actuate said first and said second controlling means.

maintain the output of the means at a first of said rates, an electrically energized bimetallic heat motor operable upon-energization to move said member in a second direction to maintain the output of the actuated means at a second of said rates, a means for moving said member in said one direction, and lost-motion means inter connecting said moving means and said controlling means and providing unobstructed movement of said controlling means by said heat motor independently of said moving means, said moving means being responsive to the output of the actuated means and operable to take up said lost-motion and to move positively said member in said one direction against the force exerted by said heat motor.

14. In an apparatus for controlling an actuated means having two rates of output, a movable controlling member for said means and normally urged in one direction toward a first position to maintain the output of the means at a first of said rates, an electrically energized bimetallic heat motor operable upon energization to move said member in a second direction to maintain the output of the actuated means at a second of said rates, a means for moving said member in said one'direction, lost-motion means interconnecting said moving means and said controlling means and providing unobstructed movement of said controlling means by said heat motor independently of said moving means, said moving means being responsive to the output of the actuated means and operable to take up said 13. In an apparatus for controlling an actuated lost-motion and to move positively said member in said one direction against the force exerted by said heat motor, and means operable by said moving means for deenergizing said heatemotor.

WALTER S. LANDON. PHILIP S. RUSSELL

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