US889355A - Thermostat. - Google Patents

Description

N 889 355. NATENTBD JUN 2 1 o o BNBNOWN. E 9 8 THERMOSTAT.

APPLICATION FILED SEPT. 4, 1906.

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P. A. BRUWN.

THERMOSTAT. APPLICATION FILED sEPT.4. 1906.

PATENTED JUNE 2, 1908.

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wwwa/awo' l PEABODY A. BROWN, or DENVER, COLORADO.

THERMOSTAT.

No. asas.

Specicaton of Letters Patent.'

Patented June 2, 1908.

Application led September 4, 1906. Serial N o. 333,044.

To all 'whom it may concern:

Beit known that I, PEABODY A. BROWN, a citizen of the United States, residingat the city and county of Denver and State of Colorado, have invented certain new and useful Improvements in Thermostats; and I do declare the following to be a full, clear, and

`exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters and figures of refer-v ence marked thereon, which form a part of this specification. l

My invention relates to improvements 1n thermostats, my object being more especially to provide a thermostat adapted for use in regulating high temperatures. p

i Ihis device while capable of use in many .different relations is peculiarly adapted for regulating the temperature of liquids as molten metal, water in a boilei or fluids of any kind more especially where the fluid 1s confined within a closed receptacle. An annunciator may be used in connection with the thermostat, whereby the temperature in the Ivicinity of the body of the instrument may be indicated at any desired location as in the ollice of the plant which may be any desired distance away from the material whose teinperature is to be regulated. I

Havinv brieilyoutlined the function of my improved device, I will proceed to describe the same in detail reference being made to the accompanying drawing in which is illustrated an embodiment thereof. A l

In this drawing, Figure 1 is a view showing my improved thermostat in elevation andin connection with a receptacle containing liquid, presumably molten metal, thesaidreceptacle and its surrounding casing being shown in section. Fig. 2 is a detail view oi the thermostat shown on a larger scale and artia'lly'in section. Fig. 3 isa view partly broken away looking in the direction of the arrow in Fig. 2.

'pin 7.

v The same reference characters `indicate the same parts in all the views.

' Let the numeral 5 desi nate a rod-and 6 a tube surrounding the ro the two parts being connected together at the bottom by a The two elements 5 and 6 are coinposed of different substances, that is to say substances possessing the properties of expansion and contraction in unequal degrees:

`oi the purposes of this specilication it may be assumed that the element 5 is com osed of iron and the element 6 of brass, the atter being more readily expansible or more sensitive to changes of temperature than the iron. These two elements may be mounted on a stationary support 8 in any suitable manner. As shown in the drawing the tube is fitted into a sleeve 9, the latter being screwed into a plate 8 which may be the top of a pot 49 containing molten metal 1() (see Fig. 1). When the device is used in connection with molten metal or other liquid or fluid whose action would have a tendency to destroy, injure or corrode the brass tube 6, the latter should be surrounded ,by an outer tube or sheath 12 adapted to protect the softer metal part within. Where the device is used in connection with molten metal, it will be sufliciently sensitive even when surrounded with the outer sheath 12 for all practical purposes. Upon the upper or outer extremity of the rod 5, is pivotally mounted an indicator 13 which as shown in the drawing has the shape of a bell crank lever ulerumed at 14 and having two ai'ms 15 and 16, respectively. 'lo the outer extremity of the arm 15 is connected one extremity of a coil spring 17 whose opposite extremity is connected with the lstationary support as shownat 1S. f Also pivotally mounted upon the u per extremity of the rod 5, is a segmentaFplate 19 the same being ivoted as shown at 20 and provided with a ever arm 21 connected with the stationary support by a springr 17 A. 'lhe two springs 17 and 17 A are substantially similar, while the lever arms 15 and 21 are. similarly arranged and both adapted lo rest upon the upper extremity ol'v the tube 6. When the temperatures vary in the vicinity of the instrument, the tube (will expand or contract as the case may beto a greater degree than the rod 5. This variation in expansion or contraction, will result in a greater movement relatively of the tube 6 than of the i'od 5 whereby the two elements 13 and 19 will be actuated. In case ol' expansion, the upper extremity of the tube 6 will act upon t i ment, and move the elenient 13 toward the left and the element 1.) toward the right or in the opposite direction.

U ointhe upper part of the segment 19, are ocated two metal contacts :22 and 23, the said contacts being insulated l'i'oni the body ofthe plate as shown at 24. Between e two ainis 15 and 21 ol the instru-V mounted on an angle plate 31 carried by the arm 16 but insulated therefrom as shown at 32.- The arm 16 is rovided at its upper eX- tremity with a ilexilile contact 35 which acts upon the pins A, electrically connected with A an annunciator as hereinafter explained. The contact 3() lies in the path of the contacts 22 and 23 and serves to make and break the motor circuit as hereinafter explained. To the angle plate 31 leads an electrical conductor 25, while the contacts 22 and 23 are connected with conductors 26 and 27 relpspectively. r1`he conductor 25 leads to a lbinding screw 33 whereby electrical connection is made with the part 31 and from it to the contact 30.' These conductors 25, 26 and 27 are connected with aI motor 23, a plug 29 being .interposed for the purpose of connecting the instrumentiwith a light or other circuit.

The upper extremity of the segmental member 19 is provided with a series of contact pins A from which lead a series of wires B to a self restoring annunciator C'through which the circuit is' completed by way of a conductor l) and a source of electricity ll. From the o posite poleof the battery a conductor F eads to the arm 16 ofthe lever 13, the circuit being 'completed through' the metal brush 35 and the pins A to the annunciator as heretofore indicated.

The contacts 22 and 23 are mounted on pins G which are adjustable in a slot H formed in the segmental plate 19 whereby the movement of the contact 30 and consequently the arm 16, necessary to close the circuit, in either direction, may be regulated at will.

The ins A are mounted in insulating material whereby the pins are insulated from each other. The wires B are connected with the pins by means of binding screws J.

As shown in the drawing (see Fig. 1) when the circuit is completed through the motor 28 andthe latter is set in motion, a valve 36 is actuated. As shown in the drawing this valve controls the passagelof gas through a pipe 37 and terminating at oneextremity in a urner 38 located underneath the pot 49 containing the molten metalor other liquid or mobile mass whose temperature is to be regulated. Connected with this valve 36 is an arm 39 to whose outer extremity is attached a connecting rod a0 attached to the motor in operative relation as shown at 41.

The apl aratus is so constructed, that it" we assume tlfiat thetube 6 ex ands and acts on the arms 15 and 21, where y' the elements 13 and 9 are actuated as heretofore explained, the contact 22 and the contact 30 will be made to approach each other, and. when these contacts enga e, the circuit. will be completed through t e motor and the valve 36 will be actuated to shut oi the as or diminish the supply as may be desired. lAt the same time thevcontact 35 will engage a teaser pin Acorresponding with one of the temperatures indicated by the iigures on the upper part of the segmental plate, and the circuit closed through a self-restoring annunciator whereby the temperature of the metal in the potwill be indicated. on the annunciator by the change in the position of one of its pointers K. It may be assumed, when the contacts-22 and 23 are adjusted as shown in the drawing, that when the motor .circuit is closed by virtue of the ex ansion of the tube 6, that the contact 35 wi engage the in A corresponding with the `four hundred egree mark on the segmental plate, thus indicating on the annunciator that the temperature of the metal in the pot is four hundred degrees. ,Now the gas or source of fuel supply having been shut off or diminished, as soon as the temperature of the contents of the pot becomes sli htly lowered, the tube 6 will contract, su ciently to allow the elements 13 and 19 acting under the iniiuence oi their s rings 17 and 17A, to move in the opposite irection, or in a direction to se arate the contact 30 from the contact 22, an cause the contact 30 and the contact 23 to approach each otherl until they are in contact, 1n which event the circuit will be again closed through the motor, and the valve 36 actuated to turn on the gas or fuel supply. The motor may be of any ldesired construction, and so regulated that as soon as the valve has been closed or opened by the movement of the motor as the case may be, the current will be automatically cut o through the motor whereby further movement 'will be prevented until there is another change in the elements of the thermostat. It is not thought necessary to go intoy the details of the construction whereby this is accomplished, since it is old-and well known in connection with the use of thermostats for regulating the dampers of furnaces, and valves for various uses. V

in case gas is used for fuel which itis assumed is the case, in the construction shown in Fig. 1, and assuming further that the gas is entirely shut off by the movement of the valve 36, in order 'to make the device 'automatic, there should of course be a ilot light connected with the apparatus wlliereby as soon as the gas is turned on it will be automatically lighted. This is another detail construction which it has been thoufrhtunnecessary to illustrate in this connection In case the instrument is used without the outer sheath 12, it would be necessary or at least highly desirable to have the lower extremity ofthe tube 6 closed, in order to prevent the surrounding liquid from passing mto the said tube.

Having thus described my invention, what I claim is:

1. A thermostat comprising an element composed of two substances possessingthe properties of expansion and contraction in unequal degrees, an electrical circuit, two movable devices carrying contacts located in the circuit, the said devices being arranged to be simultaneously acted on by one of the substances to cause the said devices to move whereby their contacts are madeto ap roach given movement whereby their contacts are' made to 'ap roach each other for the purpose of closing tlie circuit, and springs connected with the said devices and under tension to give them -an opposite movement when opposite thermal conditions exist.

3. The combination with a stationary support'and two electrical circuits, of anelement composed of' a tube and a rod'surrounded thereby, the parts being'connected and the rod protruding from the tube, two devices pivotally mounted on the rotruding eX- tremity of the rod, one of t esaid devices carrying contacts located in the respective circuits, and the other of the said devices carrying a contact connectedv to beplaced in either circuitr according to thermal conditions, springs connecting the said devices with the stationary support and under tension to give them a certain movement, the said tube forming a stop to limit the move'- ment ofthe devices under the influence of the s rings, and also serving to act onthe said evices to give them an opposite movement. In testimony whereof I aliyX my signature in presence of two witnessesi PEABODY A. BRowN Witnesses:

DENA NELSON, A. J. OBRIEN.

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