US1797369A - Thermo-electro-responsive device - Google Patents

Description

March 24, 1931. H. E. RUPP THERMO "ELECTRO-RESPONS IVE DEVICE Filed May 20, 1926 2 Sheets-Sheet 1 [26.4. kEBEETE EUPP March 24, 1931. H. E. RUPP THERMO-ELEGTRWRESPONSIVE DEVICE Filed May 20, 1926 2 Sheets-Sheet 2 nvcnl'cz ffEEBE/E T E. EUPP Chrome Patented Mar. 24, 1931 UNITEDSTATES PATENT OFFICE i I. BUPP. OI MANSFIELD. OHIO, ASSIGNOB TO THE OHIO. BRASS 001mm, OI

IANSI'IELD, OHIO, A. CORPORATION OF NEW JERSEY TmIO ILETRO -BESPONSIVE DEVICE Application fled Kay 20, 1988. Serial ll'o. 110,411.

My invention relates to a thermostatically controlled mechanism to control the opera tion of a switch or other mechanism.

I have shown the device as applied to the operation of a rotatable switch, but for the sake of simplicity, I have not shown the switch in detail, as the device can be used to control the operation of a rotary or other type of switch, as for instance, the operation of therotary switch as shown in colpending application, Serial No. 102,653, filed pril17, 1926, in the name of Edgar D. Moore, with which I am familiar and which switch would open and close the circuits to and from the device or mechanism, or the armature 'of-the device may itself be used as a switch to open or close a circuit, which in turn controls the operation of other apparatus at a distance from the device.

One of the obj ects'of my invention is to provide a mechanism which can be connected to a circuit, and when the current flowing in the circuit suddenly exceeds a predetermined amount the mechanism will operate to open the switch.

Another object of my invention is to provide in themechanism a thermo-responsive device to control the operation of the mecha-,

nism when the current flowing in the circuits exceeds a redetermined amount for a determine time.

A further object is to provide a means of protecting an electric translating -device from a dangerous rise in temperaturej Another object of my invention is to provide means for rendering the thermo-responsive control independent of changes in temperatu'reof the surrounding air. When my invention is used in connection with a rotar switch, as set forth above, for controllingt e circuits leading to electrically operated translating devices such as motors, lights, etc.,- it provides a means of protect ing the translating device from sudden overloads and also from loads sufliciently high to cause a dangerous heating of the translating device when not sufliciently high to cause the overload to operate. In other words, it will permit the translating device to carry its maximum safe load. I

I'have shown certain parts of my invention 1n the attached drawing in schematic known to those skilled in the art, and to make the disclosure in other form than shown, it

is believed would merely complicate the un-' derstanding of the invention.

My invention resides in the new and novel Fig. 6 is a sectional view on the line of Fig. 5 to show an adjustable member; on' the thermostatic control. 7

Fig. 7 shows one of the elements of the thervmostatic control.

Fig. 8 shows my device as applied to a rotar switch, referred to before, and to a trans ating device.

In the preferred construction of my relay, I employ a base member 1, preferably of nsulating material. Mounted upon the base 1 s a magnet M, which does not difi'er in EIIIICIRIB fromother well known' ma ets,

ut which comprises a core 2, end mem rs 3 and 4 secured to the core member 2 by means of screws and secured to the base 1 by means of the screws 5. The end members 3 and 4 may both be made of iron, but the end mem.- ber 3 may be made of other material. The

armature6, which is also of iron and movably secured to thejend member 3 by means of the spring 7, 1s attractedby the end member 4.

The base 1 has mounted thereon the terminal posts 8, 9, 10 and a coil 12 having the base. The coil 12, it will be noted, is connected in series in the circuit between the the post 8 by the form, as the construction is simple and well metal parts. 'Ihis construction is well known to those skilled in the art.

Mounted on the base 1' is a thermostatic responsive device T which comprises an insulating member 1.6 secured to metallic standards l7 and 17 by means of the screws 18 and 18. Mounted on the insulating member 16 is a lei-metal therinostatic'element 19 com posed of two dissimilar metals whoe tem-.

perature co-eficients are diderent i in bimetal element is well known in the trade. The element 19 is secured to the insulating member 16 by means of the screw 29 and atits distant end is a contact element 21 secured thereto which may be of metal, but preferably oicarbon.

Also mounted on the insulating meber I 16, but spaced from the element 19, is a U- shaped hi-etal thermostatic element 22 (see Fig. 7)

This element is provided with contacts 23 and 23, which are mechanically and electrically coected to the standards 17 and.

i7 respectively by being interposed between such standards and the insulating memher 16 and held in position by the screws 18 and 18, At the distant end of the element 22 is a contact member as adapted to engage with the contact member 21.,

lhe contact 23 of the element 22 is connected to the post 9 by the conductor 25., The contact 23 is connected to the post ll by means of the conductor 26. From this it will be seen that the til-shaped bi-metal thermostatic element is connected in series with the circuit connecting the posts 9 and ll and, therefore, the current flowing through the circuit connecting the posts 9 and 11 will flow through the element 22. If new a translating device, such as a motor, is connected to the posts 10 and 11 and the posts 8' and 9 are connected to the source of supply then under normal operating conditions the same current which flows through the coil 12 will also flow through the U-shaped thermostatic element 22.

Themagnet core 2 is provided with an auxiliary winding 27 which has one terminal connected to the conductor 14 through the conductor 28 and the other terminal being connected to the thermostatic element 19 through the conductor 29 and the screw 20. It will be noted that under normal conditions arouses current would flow through the coil 27, but should the contacts 21 and 24 be brought into engagement then the coil 27 will be connected between two main circuits connecting the posts 8-10 and 911. It will also be noted that when the contacts 21 and 2d are connected together that the two coils 12 and 27 will be in series and connected across the opposite circuits. in other words, the main circuits will be connected-together through the coils 12 and 27 in series. For this reason It prefer to construct the coil 27 of a high resistance material such as iron, German silver, nichroine, etc, thereby introducing scient resistance to prevent an mil-ecossary flow of current between the mains, but still accomplish the purpose of the device.

One of the objects of my invention is to provide a device which is controlled by temerature changes based upon the current it owing through the device and the time that such current flows, therefore, I find it necesthe contacts 21 and 24 separated that no sary to provide means of preventing-the theostatic elements from contacting under other conditions than those intended, and I iind that it only a single thermostatic element is used thatthis element is aficctedby changes in the surrounding temperature, or what might be termed the room temperature, such that if the thermostatic element should be set to operate under a given room temperature and a given current after flowing a length of time that this setting would vary should the room temperature vary. For this reason I employ the two therm'ostaticelenients 19 and 21 so related to each other that the space between the contacts 21 and 24 will. remain substantially constant regardless or" the changes in the room temperature, as this temperature would adect both elements 19 and 20 alike and, therefore, the space between thecontacts 21 and 24 would remain constant or practically so. With the construction shown, in which one element 19 is entire and the other element 22 is U-shaped, l find that for. all practical purposes such construction maintains the separation of the contacts 21 and 24 practically constant, but if it is desired to secure more accurate conditions then the element 19 may be made U- shaped similarto the element 22.

One function of the thernio-responsive device T is to protect the translating device Xv from a too great temperature rise, and as the device may be used with different classes of translating devices which will permit of difierent temperature raises, I provide means of varying the thermo characteristic of the thermo-responsive device, and I do this by mounting upon the thermo element 22 a rider 30 which is movable upon the element 22 and will increase or decrease the length of the element 22 through which the current can traverse thereby increasing or decreasing old the length or the element 22 which is subjected to the heating action-of the current.

'With a given current the movement of the free end of the element 22 will he greater or less, depending upon whether the rider is closer to the free end or to the fixed end of the element 22. Therefore, hy means of the rider 250 I am able to adjust the thermo-responsive device so that it will operate when the temperature of the translating device X has reached a predetermined degree or close thereto.

lhe armature 6 can he made to operate under did'erent conditions by varying the size or the spring 7.

In Fig. 8 l have shown'a rotary switch S controlled hy the operation of the armature t and this switch will controlthe opening and closing of the main line circuit leading to y the contacts 8 and 9. in Fig. 8 the switch 5 is shown in its open position. en my device is comhined with a switch S and a translating device X, as for instance a motor, the coil i2 will he energized with a normal flow of current insuflicient to operate the armature ti and also insuficient to operate the armature 6 under stunting conditions, but if while running the load on the motor X should he increased suddenly to an abnormal amount then energiaation of the coil 12 would he suiiicient to immediately attract the armature t5 and the switch S would be released to open the circuit item the source of supply.

Also, it the translating device X should he operated under a steady overload so as to on danger the same, hut such overload is not suficient to operate the armature 6, then alter such overload had continued for a pre determined time, thereby heating the translating device up to a predetermined amount,

then under such operation, when the redetermined temperature had heen reache upon the motor, the thermo-responsive device would operate to close its circuit thereby connecting the free end of the coil 27 to the circuit 25, and this amounts to throwing the auxiliary coil 27 across the two sides of the circuit :lrorn the source. of power, and current will flow therethrough, increasing the energization of the core 2, and at the same time the current through the coil 12 will he increased hy a like amount which flows through the coil 27 thereby further increasing the energization of the core 2, and which will he sufficient to cause the armature 6 to be attracted thereby releasing the spring held switch S to open the circuits from the source of ower.

From this it will be seen that I have a device forprotecting the motor against a sudden overload of a predetermined amount, or to protect the motor at a lower overload after such overload has raised the temperature to a predetermined amount.

The switch S may-consist of a rotatable insulating disc 4d and which is held under spring tension when in its'closed position, as is usual with snap switches. The disc 46 is mounted on the pin it as is also a lever oi insulating material 42, which is free to rotate I relative to the disc 40. The lever 42 is pro vided with a handle 43 by means of which the lever 42 is operated. The disc is also provided with four reciprocating contact members 44, it, 45 and is connected together by the spring members it? and 47 which are held to the plate 1' hy the screws 48. These reciprocating contacts are adapted to engage with contacts 4-9-49 and 56-50, which are secured in the base plate 1.. The contact 49 is connected to the post 51 by the conductor 52 and the contact 49'' is connected to the post 8 loy means of the conductor 53, while the contact is connected to the post 54.- hy the conductor 55 and the contact 50 is connected to the post 9 'hy means of the conductor 5d.

The armature it is provided with a catch 57 which engages with the stop 58 when the plate id is rotated to its closed position and holds the plate in such position thereby closing the circuits from it to &9" and from 59 to 50"..

To close the switch the handle 43 is re tated in a clockwise direction which moves the lever 42 into engagement with the projecting contact 45 thereafter causing a rotation of the member 4d, and this rotation continued until the catch 5'2 engages with the catch 58.

it it is desired to c on the switch h hand to operate or electrically control distant apl paratus, and this can he brought about by securing a contact a Fig. l to the base memher of such construction, as is well known to those skilled in the art, and which will engage with the armature 6 if it is desired to operate with a normally closed circuit or employ a contact as shown at a if it is desired to operate on an open circuit. In either case, a conductor would he led from the armature 6 and from the contact a or a to such device as is to he controlled by the mechanism shown in Fig. i.

It will be noted that when the thermo-responsive element closes that the two coils upon the core 2 will be thrown in series across the two sides of the complete circuit, but by constructing the coil 27 of hi h resistance material the amount of current owing under such conditions will be materially reduced thereby preventing a heavy flow of current.

ill)

' The coil 27 could be made in the form of a resistance separate from the core 2, in which case it would not add to the turns of wire on the core 2, and this construction is perfectly feasible by properly proportioning the resistance of the said coil and the ampere turns of the coil 12, so'that sufiicient. energiz'ation of the core 2 will be secured,

If the conductor 28 is connected to the conductor 13 in place of to the conductor 14 then when the thermo-responsive device closes, the current flowing through the coil 27 will not first pass through the coil 12, but by connecting'the coil 27 as I haveshown it permits a smaller number of turns in the two coils, therefore reducing the size of the dev1ce.

There are a number of modifications in my invention which will suggest themselves to those skilled in the art, therefore, I do not wish to be limited other than by my claims.

I claim:

1. An electro responsive device comprising an electro-magnet, an armature to be operated by the electromagnet, a pair of conductors adapted to be connected to a source of power and to a translating 'device, a main coil interposed in series with one of said conductors on one side of said translating device to'energize said magnet and operate said armature when the current in the conductors exceeds a predetermined value, a thermoresponsive device connected in series with the other-conductor and on the other side of said translating device, means to maintain the thermal device substantially unaflected by variations in the surrounding atmosphere,

by the electro-magnet, a

connected to a source 0 an auxiliary coil to energize the electromagnet having one .end connected to the mam coil and the other end arranged to be connected to the last said conductor by the thermalresponsive' device when the current therein is a predetermined amount for a predetermined time and means to vary the thermal characteristic of the thermal device.

2. An article of manufacture comprising an electro-magnet having a main coil and an auxiliary coil, an armature to be operated power, the main coil being interposed in one of the conductors to effect movement of the armature when the amount, means comprising the auxiliary coil and a thermo-responsive device havin a self-heating, thermal current switch mem er arranged to connect the main coil to the other conductor'path when-the current flowing through the circuits'for a time has raised the temperature of the thermo-responsive device to a predetermined value but to main-- tain said connection open for all temperatures below said value.

3. In combination, a circuit comprising a pair of conductors, a translating device conair of conductors 1,7e7,see

nected to said conductors to receive power therefrom, a switch for connecting said conductors to a source of power, said switch being biased to open position, a catch for hold ng said switch in closed position, an electromagnet for releasing said catch, said electromagnet having a winding in series with one of said conductors and arranged to energize said electromagnet to release said catch when the current in said winding reaches a predetermined value, a shunt circuit having impedance therein, athermal element in series with one of said conductors-arranged to connect said shunt circuit across said conductors in parallel with said translating device when the current in said translating device persists for a predetermined period .of time at a predetermined value less than that required-to energize said winding for releasing said catch, said shunt circuit being connected to the end of said winding adjacentsaid translating device so that current passing through said shunt cir cuit passes also through said winding to supplement the current passing through said translating device in releasing said catch.

4. In combination, a pan of conductors, a

translating device connected to said conduc: tors for recelving power therefrom, a swltch connection of both'of said conductors with i said source of power, a catch for holding.

said switch in closed position, an electromagnet for releasing said catch, said elctro-- magnet having a winding in series with one of said conductors and arranged to release said catch when thecurrent in said winding reaches a predetermined value, a supplemental winding for said magnet having one end thereof connected with the end of said first named winding adjacent said translating device, a thermal element in series with the other of said conductors and arranged to connect the other end of said supplemental winding with said lastnamed conductorv to bridge said supplemental winding across said conductors in parallel with said trans-' lating device, said thermal element being. arranged to close said parallel circuit when Q the current in said translating device persists for a predetermined period of time at apredetermined value less than that" required to energize said first named winding'sufiiciently to release said catch, the combined eflect of said electromagnet windings being suflicient when said thermal element is closed to release said catch. a

In testimony whereof I afiix my signature.-

HERBERT n. RUPP.

Images