US1894842A

US1894842A - thermostat switch

Info

Publication number: US1894842A
Application number: US521578A
Authority: US
Inventors: Appelberg Carl Wilhelm
Original assignee: BIRKA REGULATOR AB
Current assignee: BIRKA REGULATOR AB
Priority date: 1930-03-27
Filing date: 1931-03-10
Publication date: 1933-01-17
Anticipated expiration: 1950-01-17
Also published as: GB365877A; FR713802A; DE558579C

Description

Jan. 17, 1933. c. w. APPELBERG THERMOSTAT SWITCH Filed March 1o`, 1931 rames .im 17, laas mio rr w www im.,

BIRRA BEGULTQR, @E

.llppllestom flle Harsh MU, Bertolt Ilo, lltlpl, om@ :im Morell 537i, mt).

` in thermostat switches of the kind which lor the purpose of increasing 'the ecierlcy et the -tlieririostat are enclosed in evscueted reeeptacles or in. receptacles lillerl 'with en ilo.- ert gas. l o

According to the invention the ortion of the thermostat deformable throw/1w.. ture Variations is composed of e plurslity of coaizially isoosed bimetallic plstes or flisljs threecl on to a rorl` end tearing with like sides against eacli other, sai@ drslrs essernupon s chan e in temperature more or less cup shape form im suoli that tlie deformation movements olf the are scldecl and together effect a cor' ect moroment is. the longitudinaldirectiono lise roel.. The invention is particularly' licslole to suoli thermostat switches contest is 'formeel ley coexisl r which are axially displacealile i to eecli other ano the two soljsc which normally laear egairist lo this type of thermostat o o s, disks ere prereraloly threacl on to one ol the contest rods, whereby 'the liest sensitive element is obtained in the simplest possilele marmer anclat the Sametime partieulerly ecient i-orm. s

The invention will be more closely described "with reference to the aocsmpanyirig drawing' showin two different em'lnoeliments oit the same, igure l is an ssiel section through the thermostat switch sccorcling to one emloodiment of the invention, the switch losing shown in closed oonition. Figure 2 shows the same section after the contacts.

here loeeri separated tlirougli heating., Fig ure 3 is en View oi tlie switch sliotm in Figure l. l escl o sliow iii ses tion ariel on s. larger loirsetsllic clislrs in normal end in deformed condities spectirely7 Figures 6' l es tions through the thermostat switch ecoorrl ing to the seconcl embodiment. Figure 8 shows in section and on s larger seele the system of loimetallic disks serving to erlect the closing of the contacts of the embodiment shown in Figures snel lll.

le. the embodiment illustrated in Figures l to 3 the thermostat contact is enclosed in s cylindrical receptacle preferably of inf sclatingg meterial. The tliermostat contact is 'formed by two coaxial rods 2, 39 one o Wliicli, 2, is screwed into e metal sleeve dis posed in one eml Well the cylindrical recegtacle Whereas the opposite rofl 3 is slideloly supportecl in tlie other enel Well. The two adjacent ends ot the' rocls ere normally held in contact with eech other ley s helical spring 5 inserted between collar on the rod 3 and the escl Well ol the receptacle. On 'to the portion of the rofl el-projecting outside the receptacle aretlireed a plurelitgT of loimetallic plates or clislzs 6 between e shoulder 7 on' the end wall or tlie receptacle ariel a mit 8 screwecl ori to the outer escl of the roel 3. @sly tour such clissts src illustrated om the .drawing-g but any number may los chosen in sccordance with tire desired magnitude of contact movement. @ne external concluctor 9 ol the switch is comiectecl to the sleeve 4 sied the other l0 is pressed between tloe mit 8 ari-rl an aloperteiriieg loclr est 8.,

mEsch oi the loimetsllic disks 6 is composed or? two metal layers a, t haring rlierelit co elicients of experisiori, The disks-6 ere clisposerl together im e, row iri such e way that the rst one, the third, the li'th etc. reckoned from the receptacle torri the layer a llas/ieg the larger coeicierit oil expansion towarcl 'the receptacle Whereas the other flisls are turned the opposite wey. Consequently t'wo and two of the disks beer against each other with their layers b Whereas the different couples of disks bear against each other with the layers a (Figures l and 5).

Sli

The bimetallic disks 6 are made in such a way that they are substantially plane at nermal temperature, as will be seen from Figures 1 and 4. When heated the layers a 'expand more than the layers whereby the disks become cup-shaped, the left disk of each couple of disks turning the convex side, the other disk on the other hand turning the concave side toward the receptacle 1. lin deformed condition the disks bear-acainst each other near their centers and at thelr circumference respectively, as'shown in Figure 5, and the column vformed by the disks will thus when Hated extend in an axial direction pressing the nut 8 outwards, whereby the contact is broken. If the disk at normal temmay be adjusted by means of the nut 8 whereby the limit temperature at which the contact is broken may be regulated. l When the bimetallic plates, upon a .decrease in temperal y ture, return to their normal plane condition the rod 3 is again brought into contact with the other rod 2 under the action of the helical spring 5'.

' If desired annular washers may be disposed between the diierentv bimetallic plates, either closely surrounding the rod 3 or inserted between the plates at their circumference.

n the embodiment according to Fi ures 6 and 7 the helical spring 5 is dispense with. The restoration of the rod 3 to contact position is here brought about by means of a system of bimetallic disks 11, said system being similar to the disk system 6 but adapted to operate in an opposite manner, the disks 11 being normally cup-shaped but approaching the plane form at rising temperature. The disks 11 are threadon to the rod between the locknut 8 appertaining to the nut 8 and a fixed support 12 which through arms 13 is secured to the receptacle 1. When heated the disk system 6 expands as inthe former case Whereas the system 11 is contracted in an axial direction, and consequently the nut 8 'Will, as in the previous embodiment, be

pressed outwards. At a subsequent cooling the rod 3 is forced back to its contacting position through the Vexpansion of the column 11 and the contraction'of the column 6.

The thermostat in its entirety may be enclosed in a glass tube 14 preferably disposed concentrically about the former which glass tube referably is evacuated or filled with an indi erent gas. The thermostat may be adapted to be actuated' either under the iniuence of temperature changes in the surroundings or by means of a special heating winding which latter may be disposed outside meenam or inside the glass tube, in the latter case preferably on a supporting cylinder secured to thev receptacle 1 and enveloping the bimetallic plates.

-instead of adapting the bimetallic disks operating rod longitudinallysli able in saidl receptacle, a pluralit l of bimetallic heat sensitive plates slidab y thrust onvsaid rod with like plate sidesv facing each other, and means for transferring reciprocatingl heat deormation movements -of said plates to said ro 2. A* thermostat electrical switch disposed in a receptacle and com rising a stationary rod shaped contact mem er mounted in said receptacle, areciprocable rod shaped contact member slidably mounted in said receptacle coaxially with and in opposition to said stationary member, a plurality of bimetallic heat sensitive platesfslidably thrust 0n said reciprocable member with like plate sides facing each other, and means for transferring reciprocating heat deformation movements of said plates to said reci rocable member.

3. A thermostat electrical switch disposed in a receptacle and comlprising a contact o erating rod longitudina y slidable in sai receptacle, a system expansive to heat and a system contractive to heat, each system having a plurality of bimetallic plates slidably thrust on said rod with like plate sides facing each other, and means for` transferring heat y expansive and heat contractive movements of said two systems to said rod to reciprocate same.

4. A. thermostat electrical switch disposed in a receptacle and com rising a stationary rod shaped contact mem er mounted in said receptacle, a reciprocable rod shaped contact member slidably mounted in said receptacle coaxially with and in opposition to said sta` tionary member, a system expansive to heat and a system contractive to heat, each system having a pluralit of bimetallic plates slidably thrust on sai reciprocable member with like plate sides facing each other, and means for positively transferring heat expansive and heat contractive movements of said two sysv tems to said reciprocable member to reciprocate same.

5. A thermostat electrical switch disposed in a receptacle and comprisin a contact operating rod longitudinally sli able in said receptacle, as stem expansiveto heat having a plurality o normally Hat bimetallic plates slidably thrust on said rod withlike plate msnm sides facing each other, a system contractive to heat having a plurality of normally cup shaped bimetallic plates slidably thrust on said rod with like plate sides facing each other, and means for transferring heat ex-u pensive and, heat contractive movements of said two systems to said rod to reciprocate same.

5. thermostat electrical switch disposed in a receptacle and compising a stationary rod shaped contact mem receptacle, a reciprocable rod sha ed contact member slidably mounted in sai receptacle eoaxially with and in opposition to said stationary member, a system expansive to heat having a plurality of normally flat bimetallic plates sldably thrust on said reciprocable member with like plate sides facing each other, a system contractive to heat havin a plurality of normally cup sha ed bmeta lic plates slidably thrust on sai reciprocable member with like plate sides facin each other, and means for positively trans erring heat ex ansive and heat contractive movements o said two systems to said reciprocable member to reciprocate same.

In testimony whereof I ahx m si CARL WILHELM APP ature. B RG.

r mounted in said'