US2524334A - Control circuit for electromagnets - Google Patents

Description

A. E. SPINASSE ETAL CONTROL CIRCUIT FOR ELECTROMAGNETS :s Sheets-Sheet 1 Filed NOV. 28, 1944 3nnentom 5 A m 2 0 0 m w m I I HHI IHI I I ILI H H HH .M/w M o 7 /|||||.|.l II II FILE? i 9 u 6 0 w n m Q filrpllll 4 5 1 5 5 3 m m x u U W% 3 1950 A. E. SPINASSE ETAL CONTROL CIRCUIT FOR ELECTROMAGNETS 3 Sheets-Sheet 5 Filed Nov. 28, 1944 Fig.7.

Fig.6. I y snvemm Patented 0a. 3, 1950 2,524,334

UNITED STATES PATIENT OFFICE CONTROL CIRCUIT FOR ELECTROMAGNETS Arthur E. Spinasse and William H. Pumphrey, Sr., Mount Vernon, Ohio; Herman Cornell administrator of said Arthur E. Spinasse, deceased Application November 28, 1944, Serial No. 565,552

3 Claims. (Cl. 175-335) This invention relates to electrically actuated solenoid devices for the control of dampers, check valves, and control valves used in supplying liquid or gaseous fuel to temperature control systems, and while the invention is illustrated in connection with systems of the above type, its use is by no means so limited.

The main object of the invention is to provide a solenoid actuated device capable of exerting a high actuating effort but capable of exercising a holding action with a greatly reduced, and

power by applying an appreciably greater electrical current to the coil of the electro-magnet during the period of time the plunger of said solenoid is in movement from an inoperative energized position to an operative de-energized position.

A further object of the invention is to provide a device employing an exceptionally small but powerful solenoid coil having auxiliary holding means effective when the coil is de-energized, so

as to require energization of the coil for short intervals only so as "to the coil.

Other objects of this invention are the low initial'cost, compactness and flexibility in the utilization of the device.

Further objects of this invention will be apparent from the following specification taken in connection with the drawings wherein like symbols refer to like or corresponding parts throughout the several Views in which:

Figure 1 is a front vertical view illustrating a form of theinvention.

Figure 1a is a plan view of the plunger support shown in Fig. 1.

Figure 1b is a side View of the switch armature supporting pin.

Figure 2 is a top plan view in part of Fig. 1.

Figure 3 is a front view in part of a modified form of the device in an operative position.

Figure 3a is a. plan View of the plunger supprevent overheating of port shown in Fig. 3. Figure Bbis a side view of the armature supporting pin.

Figure 4 is a view of a modified form of the invention.

Figure 4b is a side view of the armature supporting pin shown in Figure 4.

Figures 5, 6 and '7 show various applications'of the solenoid device.

Figure 8 is a schematic View" of a modification which may be used with the device.

Referring to the drawings'and more-particularly to Figures 1 and 2, character I designates-a solenoid coil, 4 a transformer primary winding, and 3 a secondary transformerwinding. 5 is essentially a single unit laminated iron core having leg portions IOI and I02, and adapted to receive said primary and secondary windings, also the solenoid coil within which a plunger It operates. Portion 20f solenoid coil I is shown as overlap-ping portion IOI of said iron core and an other portion, I 02 of the same core being adapted to receivethe said transformer windings 3 .and 4. 56 are mounting screws for said iron core. Conductor 14 of solenoid coil I leads to an electric switch 28. Conductor 61 of the same circuit leads to a source. of power 52 by way of conductor 66 and conductor 69 of primary winding 4. Theironcore portion I02 also has. the secondary winding 3 including, conductors I3 from said secondary winding 3 to thermostat switch 44, conductor '10 from said switch to signal device 62, conductor II to electro-magnet coil I4 and from said coil, conductor I2 leading to said secondary winding 3 which is adapted to periodically energize the electro-magnet I4, and signal device 62, by the action of the thermostat switch 44. The electro-magnet I4 includes a coil I 5, and an iron core I6 assembled as shown and supported by screws 56.

As shown in Figure 2, 41 is a suitable nonmagnetic plunger tube, 48, 49 and 50 are suitable insulating materials and 5| indicates a clearance between the plunger 6 and tube 47. Winding 2 is a continuation of the solenoid coil I winding I, the same being so placed and arranged as to encircle both plunger 6 and a suitable portion of iron core 5. 4 is the transformer primary winding having connections 68 and 69. Nos. 66 to 15 inclusive represent conductors.

Extension 8 of solenoid plunger 6 is provided with a switch armature supporting pin 1, a support 9 and support pin I0 therefor including a resting support II Wlth'bEBLIlHg opening l3, said support 9 being held in position b screws 55. The electromagnet switch has an L shaped arm I8 pivoted at I9 for coaction with switch 28 and magnet I4, said arm I8 having a non-magnetic portion 2| and magnetic portion 20, the former having an offset spring 22 adapted to be engaged by supporting pin 1 in the upward movement of plunger 6. 23 are mounting screws for said spring. The L shaped portion of said arm I8 is further provided with spring 24 and spring stop support 25 including mounting screws 26. This portion of arm I8 is also provided with a switch operating member 21, made of a suitable insulating material such as fiber, or the like. This switch operating member 21 is preferably threaded and is adjustable for controlling the operation of the different contacts of switch 28 which thus regulates or determines the time of energization and de-energization of the solenoid coil 6 in accordance with the elevation of the rising plunger therein. This is important for reducing or even eliminating plunger pounding against any part of the iron core and for adjusting and securing smooth engaging action between the switch armature supporting pin I, spring 22, the latching pin 37 and inclined surface I2 of the support member 9 herein described. The structure of the solenoid is, therefore, such that the switch operating member ma be adjusted for de-energizing the coil at desired points in advance of the ultimate stopping operative position of the moving solenoid plunger. This not only permits stopping the plunger at desired predetermined positions but smoother action of the coacting parts is also secured. 33 designates an electromagnet holding device including a magnetic arm portion 34, a non-magnetic L shaped ortion 35 pivoted at 36, and latching and holding pin 31 adapted to engage armature support 9, the latching pin spring 38, latching pin key 39, and holding armature return spring 40 adapted to reduce friction and wear between members 3! and 9. 42 is a mounting screw for spring 40, M is a limit stop for said spring, and 43 is a limit stop for portion 34 of arm 33.

Electric switch 28 as shown in Figures 1 and 3 consists of one closed and one open circuit, three spring blade contacts, two position type, including primary winding spring blade contact 30, contacts 30 and 3| shown in a closed position,

and center common contact 3| and solenoid coil contacts 29 and 3| shown in an open position. Spring blade contact member 3| has an extension 32 which is adapted to be periodically engaged by the switch operating membe 21.

44 is a thermostatic electric switch including a temperature sensitive bimetal element I6 on which is mounted a contact 45 adapted to engage and thereafter disengage contact 46.

An electric power saving and safety device may be used in connection with switch 28 or otherwise in the circuit of the solenoid coil for limiting the time period in which winding I and 2 may remain energized, said device comprising a bimetallic spring blade member 92 upon which is wound a resistance wire 93, one end of which is connected to member 92 and the other terminal thereof to member 94. Either the spring blade member 92 or resistance wire 93, or both, are covered with suitable heat resisting and electrical insulating material such as is known in the art.

Holding and releasing lever 51 made of a suitable insulating material such as fiber, is pivoted at 58 and carries a spring blade hook member 59 supported by screws 60 adapted to engage and thereafter disengage the upper end of bimetallic member 92. The tilting movement of member 51 is limited by stops 6 I.

In the event that the windings I and 2 should remain energized beyond a predetermined period of time, the resistance wire 93 will become heated and in turn also will impart some of its heat to the bimetallic spring blade 92 causing the same to warp so that the upper portion thereof will engage the spring blade hook member 59, at the same time moving contact 29 from contact 3| thereby opening the power circuit of solenoid windings I and 2.

When pressure is applied to end of member 51, member 59 is caused to disengage member 92, thus releasing said member 92.

62 is a signalling device including auto-transformer winding 63, iron core 64 and neon lamp 65, said signal device being adapted to indicate when contacts 45 and 46 of the thermostat switch 44 are in contact. It will be noted that the device 62 is energized when contacts 45 and 4B are engaged and said indicator is de-energized when said contacts are disengaged. Conductors I1 and 18 energize the neon lamp indicator 65. When so desired, one o both signalling device 62 and power saving safety device members may be omitted without affecting the proper operation of said transformer solenoid device, providing, of course, the opening of the circuit caused by the removal of said device is re-established by means of a suitable conductor.

In Figure 8, a fractional part view of Figure 1 is shown, wherein member 4 is the transformer primary winding of said transformer solenoid device and 3 is the secondar winding. For normal operation, secondary current is obtained from points I2 and 55 of said secondary 3. To obtain additional secondary voltage, points I2 and 54 of secondary 3 may be used to compensate for voltage drop incurred in instances where it is necessary to locate thermostat switch 44 an excessive distance from said transformer solenoid device.

For clarity, Figure 3 shows a. slightly modified form of the device illustrated in Figure l in an operative position. In this figure the signal device 62 and the power saving and safety device shown in Figure l are omitted. A means for adjusting the position of the pole pieces of electro-magnet I5 is also shown wherein the electromagnet is mounted on a plate I32 having a slot I34 through which a screw or bolt I35 passes to a main support I29, the slot being larger than that of the cross section of the bolt so that, by means of a washer I33 and said screw or bolt, the magnet may be adjusted to desired position on said support with the pole pieces of the magnet in positive contact with the magnetic arm portion 34 of holding armature 33, including the magnetic arm portion 20 of switch arm I8. I30 and I3I represent rectifiers which may be used in circuit leads "II and I2 of the electro-magnet I5.

When desired a manual switch may be provided as shown by lines in Figure 3, said switch including extension leads to lines 61, 68 and I4. Different positions of contact bars are indicated by vertical dotted lines wherein position (A) transformer primary and secondary windings are energized; in position (B) transformer primary, secondary and solenoid coil are energized, and in position (C) solenoid coil is energized, the primary winding is de-energized and the secondary winding is further energized as heretofore described, thus substantially duplicating, by said hand switch, the action of the electro-magnetically operated switch 28. In such case switch 28 and arm I8 may be omitted while retaining proper conductors in the circuits of the device. In this manner the operation and control of the solenoid coil and electro-magnet including the operation and control of the holding member 33 may be had through the manipulation of said manual switch.

A three point switch I! shown in Figure 3 may be provided, wherein when contact 61 is made thermostat 44 controls the electro-magnet I5, when contact 98 is made thermostat 44 is idle but the electro-magnet may be manually controlled by said switch I! between contact point 98 and idle point I63.

In Figure 4 is shown a modified form of the invention wherein the improved holding member 33 and support 9 of plunger extension ID are used in connection with a separate solenoid coil 95 and a separate step down transformer 96 is used to energize a coil I4 of an electronagnet I5 by the action of thermostat switch 44 by means of lead Wires II, I2 and 13. Electric switch 28 is adapted to energize coil 95 by means of a separate circuit comprising leads 61, I5 and 14. When contacts 45 and 46 of the thermostat switch 44 are closed, thereby energizing the electromagnet I 5, switch arm I8 is attracted toward and to electro-magnet I5, the holding member 33 due to its greater mass follows the action of switch arm I8 also moving to its operative position on magnet I5, this action of switch arm I8 causing contact operating member 2'! to close contacts 30 and 3I of switch 28 thereby energizing coil 95, causing solenoid plunger 6 to be moved to an operative position and thereafter held in its operative position by the action of plunger support member 6 engaging the top of latching pin 31 of holding member 33 as shown in Figure 3, and at the same time pin I engages spring 22 raising switch arm I8 which in turn causes member 21 to retract and contacts 39 and 3| to open, thus de-energizing coil 95. Plunger 6 continues to be maintained in its operative position by support member 9.

When contacts 45 and 46 of thermostat switch 44 separate, magnet I5 is de-energized, releasing members I8 and 33 to the position shown in Figure 4 causing plunger 6 to return to its inoperative position, contacts 36 and 3| remaining open by the action of spring 24 of member I8.

Figures 5, 6 and 7 illustrate examples of possible combination features and various applications of the invention. For example, in Figure 5, solenoid plunger extension 8 is shown connected to arm 99 of feed valve BI] adapted to supply liquid or gaseous fuel from a source, through a nozzle 8|, into a heating furnace 82. In Figure 6 plunger extension 8 is shown connected by suitable means to operate a damper 83 and check 84 of heating furnace 65. In the position shown plunger extension 8 is in an oif position with damper 83 closed and check 84 opened by means of cable 86 and 8! and pulley members 88. In Figure 7 plunger extension 8 is shown with a link 89 and arm 90 arranged to operate an enclosed electric switch or rheostat 9 I.

In the operation of the present invention as shown, in Figure l solenoid plunger 6, and electro-magnet holding armature 33 are shown in a standby or inoperative position. In electric switch 28, contacts 36 and 3! are shown in an on position. Contacts 45 and 46 of the sensitive temperature switch 44 are shown in an off position. Conductors 61 and 68 are shown connected to a source of suitable electric power 52. By means of contacts 3| and 30 and conductors 66, 61, 68 and 69, transformer winding 4, core 5 and secondary winding 3 are energized. The control switch 44 which is in the form of a room rheostat includes a bimetallic element 16 to which is secured a contact 45 adapted to engage a fixed contact 46. Upon a fall of temperature bimetallic element I6 moves contact 45 into a position engaging contact 46.

As heretofore pointed out, the secondary winding 3 is energized and upon the instant that contacts 45 and 46 are engaged, switch arm I8 is attracted against the force of spring 24 to the iron core I Bcausing contact 3I, by action of contact operating member 21 engaging extension member 32, to move toward and engage contact 29 before disengaging contact 30, thus energizing solenoid coils I and 2 shown in Figure 2. Coil 2 is adapted to energize iron core portion IUI and is also a continuation of coil I. When contacts 30 and 3| are disengaged, primary winding 4 is de-energized.

Portion 2 of the solenoid coil I is also a transformer primary winding designed to have a much greater number of ampere turns than primary winding 4 for the purpose of greater excitation of the iron core 5, thus secondary winding 3 will deliver a much higher voltage to electro-magnet coil I4 to assure the proper operation of holding member 33, by overcoming the resistance of spring 40. Holding member 33 will thus engage electro-magnet pole piece I6 while at the same time plunger 6 is moving upward.

By the action of inclined surface I2 of plunger support 9, latch pin 31 is forced against the action of latch pin spring 38, plunger 6 continuing in an upward movement thus permitting pin 1 on plunger extension 8 to engage spring 22 and compressing same, toward and against switch arm extension 2i, thereby moving switch arm I8 upward and away from iron core I6 of the electro-magnet I5. While switch arm member I8 is being forced to disengage member I6 of electro-magnet I 5, contact 3I engages contact 3!] re-energizing primary winding 4 while at the same time disengaging contact 29 de-energizing solenoid coil and thus causing plunger 6 to be latched up by latch pin 31 and plunger support member 9. Molding and releasing member 33 and latch pin 31 are by now in an operative supporting position thus maintaining plunger 6, while de-energized in an operative position. The transformer solenoid device is now in an operative position.

With a rise in temperature, thermostat contacts 45 and 46 are by the action of the bimetallic element I6 caused to disengage, and by reason of the electro-magnet I6 becoming de-energized permitting member 33 to return to its former position, thereby releasing plunger 6 which is now free to return to its former inoperative position.

The saving of electric power of this invention will be apparent. While said alternating current transformer solenoid is in an inoperative position when plunger 6 is down, the power consumption is for example one watt. While the plunger 6 is being lifted to its operative position, the power is increased to say namely solenoid coil 550 watts and the electro-magnet 60 watts, totalling 610 watts. However, due to the almost instantaneous movement of the plunger, this increased consumption of current occurs only for a fraction of a second. When plunger 6 is moved to an operative, position, coils l and 2 of the solenoidare no longer energized, the plunger being maintained in its operative position by holding member 33 as shown in Figure 3. Primary winding 2, secondary winding 3, and electro-magnet [5 are now energized and require only a small amount of current to hold the plunger holding member 33 in its operative position, for example only 12 watts or less.

It is to be understood that the power consumption of the said transformer-solenoid device may be varied so as to be adaptable to any modifications for which it may be designed to operate, all within the ratio of power saving above described. Theratio of power saving also progressively increases proportionately with the increase of the size of the solenoid device. The power of the coils I and 2 may be materially increased without substantially increasing the size and power consumption of the transformer device which serves to supply current to operate the above named electro-magnet.

Since solenoid coil member 2 is energized for only a sufficient period of time to actuate plunger 8 from an inoperative position to an operative position, said cell member ma be designed to have a much greater lifting power without overheating, plunger 6' being thereafter maintained in its operative position within the de-energized coil by suitable means other than the coil and, therefore, said solenoid device may be constructed extremely small and very powerful.

In some instances the solenoid coil and electromagnet may also be operated by direct current; member 92 also denoting a suitable source of power which may be a storage battery, a generator, a rectifier or the like corresponding to the nature of the power to be employed.

It is obvious that various other changes and modifications may be made in the details of construction, position and/or the arrangement of parts or design of the above described embodiments or this invention without departing from the spirit thereof. Such changes and modifications being restricted only by the scope of the following or appended claims.

What we claim our invention is:

1. A transformer solenoid device comprising an iron core having three parallel legs comprising a middle leg and two outside legs, primary and secondar windings mounted on one of the outside legs in inductive relation to each other, a solenoid mounted between the middle leg and the other outside leg, and having a portion in flux threading relation with said primary and secondary windings, a plunger movable in said solenoid, means for energizing said primary winding and solenoid, electromagnetic switching means connected to said secondary winding for causing energization of said solenoid to draw said plunger into said solenoid, and then to deenergize said primary winding, means actuated by said plunger when lifted, for re-energizing said primary winding and then deenergizing said solenoid, and mechanical holding means for retaining plunger in said solenoid when the solenoid is de-energized.

2. A solenoid operated device comprising an iron core having first, second and third, legs, a primar winding and a secondar winding on the first of said legs, a solenoid winding between the second and third of said legs, and having a portion in flux threading relation with said primary and secondary windings, a plunger for said solenoid, means for energizing said primary winding and said solenoid winding, a switch for controlling both said primary and said solenoid, an electro-magnet in circuit with said secondary windin a pivoted member controlled by said electromagnet for actuating said switch for closing the circuit of the solenoid winding and then opening the circuit of the primary winding, means actuated by said plunger when lifted, for re-energizing said primary winding and then deenergizing said solenoid winding, latch means controlled by said electromagnet for mechanically holding said plunger in said solenoid winding when the solenoid winding is de-energized, and thermal means in circuit with said electromagnet for controlling said electromagnet.

3. A solenoid operated protective device comprising an iron core having at least three legs, a solenoid winding disposed between two of said legs and having a portion embracing one of said legs, primary and secondary transformer windings carried by one of said legs adjacent to the leg carrying said portion of said solenoid winding, a plunger for said solenoid, a source of current connected to said primary winding and said solenoid winding, electromagnetic switching means in circuit with said secondary winding for causing energizaticn of said solenoid winding to lift said plunger and to subsequently break said primary circuit, means actuated by said plunger when lifted, for re-energizing said primary winding and then de-energizing said solenoid winding, and latch means operated by said plunger and retained by said electromagnct for holding said plunger in said solenoid winding when the winding is de-energized.

ARTHUR E. SPINASSE. WILLIAM H. PUMPHREY, Sn.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 95,174 Wells Sept. 21, 1869 272,511 Angell Feb. 20, 1883 673,209 Lingemann Apr. 30, 1901 1,204,486 Randall Nov. 14, 1916 1,295,020 Fallek Feb. 18, 1919 1,322,229 Chudzikowski Nov. 18, 1919 1,498,818 Smith June 24, 1924 1,767,058 Eiseman June 24, 1930 1,798,657 Grissinger Mar. 31, 1931 1,843,966 Adams Feb. 9, 1932 1,979,127 Narrick Oct. 30, 1934 2,069,578 Eaton Feb. 2, 1937 2,140,386 Jones Dec. 13, 1938 2,352,985 Warrington July 4, 1944

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