Патент USA US2109169код для вставки
Feb. 22, 1938. 2,109,169 0. S._FIELD THERMAL OPERATED CIRCUIT CONTROLLING DEVICE Filed Aug. 15, 1934 \\ \ \ 1./! FIG. . 3. 1171/!!! 11/ INVENTOR _ 0. 5 9’ fkwwm m ATTORNEY I 2,109,169 Patented Feb. 22‘, 1938 - UNITED STATES PATENT‘ OFFICE" 2,109,189 THERMAL OPERATED CIRCUIT CONTROL ‘ ~ LING DEVICE ' Oscar S. Field, Rochester, N. Y., assignor to General Railway Signal Company, Rochester, N. Y. Application August 15, 1934, Serial No. 739,981 1 Claims. (Cl. 200-122) ' This invention relates to circuit controlling devices of the thermal element type. resistance wire in the ‘usual way, one end of this heating coil being soldered or welded to an an ' The heating and cooling of bi-metallic thermal chor member 4 in the stem of the bulb B. I In the arrangement shown, two resilient con tact members 5 and 6 are anchored at their lower ployed to open or close contacts on a time inter-» ends in the stem of the bulb B, and are connected together at the upper ends and to the bi-metallic val basis. In the interests of economy and ef ?ciency, such thermal elements may be enclosed ~ strip 2 by a tie-piece or driver member‘ 1 of suit in an evacuated or gas ?lled bulb, as disclosed able insulating material, such as mica. Station ary contact members 8, 8', and ill of similar con 10 10 for example, in my Patent 2,035,426, granted elements in response to the flow and interruption of electric current may be advantageously em March 24, 1936, on application, Ser. No. 634,019, ?led September 20, 1932. In accordance with this invention, generally speaking, it is proposed to provide for the ready adjustment of the time 01' operation of such en closed thermal elements by varying the rate at which heat may be conducted or radiated from the heating element, either by changing the pressure of the gas in the enclosing bulb, or by 20 ' changing the area exposed to the external air of’ a heat conducting member extending into the struction are anchored at their lower ends to en gage the contact members 5 and 6. These con- - tact members may be made as a whole of suitable contact material, such as a nickel alloy; or con tact pieces may be attached to these members at 16 the points of contact. One end of the heating coil 3 is connected to the contact member 5. The arrangement .of ‘contacts illustrated is merely typical; and‘the contact members may. part apparent, and in part pointed out as the be arranged to open or close contacts in the 20 heated or cooled condition of the thermal strip i. The contact members and the anchor} member 4 for the heating coil are connected by wires to; pins ii in an insulating base C, attached to the glass bulb or container B in accordance with reg 25 description progresses. ular practice. ' bulb into contact with the thermal element. The various characteristic features, advan tages, and attributes of the invention will be in ’ The accompanying drawing illustrates in. a simplified and diagrammatic manner certain spe clflc embodiments of the invention. Fig. 1 shows 30 the structureof an enclosed thermal element having provision for adjusting the time of its operation by varying the pressure of the gas iri the enclosed bulb. Fig. 2 is a fragmentary view illustrating the application of a heat conducting part to an enclosed thermal element device for varying its time of operation; and Fig. 3 is an other fragmentary view illustrating a modi?ca tion of the heat conducting part. Referring to Fig. 1, the thermal device com 40 prises a bimetallic strip. lot the usual type and construction, ‘such as brass and- “Invar" strips fastened together. This member i is anchored at its lower end in the stem oi a glass tube or bulb B,'in the usual'way and in accordance with well-= known practice. A similar bi-metallic strip 2 is welded or otherwise rigidly fastened to the up per end of strip I; and the two strips i and 2 are disposed in an opposing relation, so that they will be deformed in opposite .directlons by a change in the temperature of both, thereby main . r In the embodiment of the invention illustrated in Fig. 1, ‘a ?exible metallic diaphragm l2 of bronze or other suitable material, preferably cor rugated, is attached to the upper end of the glass 30 bulb B, the edgeof this diaphragm forming a gas-tight seal with the glass. An adjusting nut it in a bracket or stirrup i4 suitably secured to the base C, is arranged to deform the diaphragm l2. After the parts have been assembled in the glass tube B and the tube is evacuated in ac cordance with the usual practice, it is preferably ?lled with inert gas such as argon or nitrogen, to a pressure conforming with the time character istics desired. ' strip 2. Consequently, the upper end of the two strips is moved or displaced. This movement is 45 assumed to be to the left to open contacts 8-! and 5-H, and to close contacts 5-8. The time taken to raise the temperature of the strip l suf ?ciently to cause the necessary displacement to operate these contacts seems to depend on the 50 taining the upper end of the two strips in sub- ‘ rate at which heat may be conducted or dissi stantially the same position witli relation to the. pated, as well as the rate at which the heat is lower end, so as to compensate for gradual supplied. Experiments indicate that the rate at changes in ambient’ temperature. The lower 55 strip i is heated by a coil or ?lament I of suitable 40 When electric current is supplied to the heat ing coil 3, the temperature of the lower bi-metal lic strip i is raised relative to that of the upper which the heat is dissipated ‘from the thermal strip l is due to a large extent to conduction 55 2 2,109,169 through ‘the gas in the tum; and it has been found, that by varying the pressure of this gas, the rate of dissipation of the heat may be ma terially changed so as to increase or decrease within certain limits the time required to operate the contacts for the same heating current. Ac~ cordingly, this invention contemplates the prom vision of the diaphragm i2, or equivalent means, by which the pressure of gas within the tube can W be readily varied after the device has been as sembled, for the purpose of adjusting the oper ating time of thermal operated circuit controllers, either to give the same time for a group of like '15 devices in spite of manufacturing variations, or to adjust the same device for different operating times for different applications. Fig. 2 illustrates another construction in which a heat conducting member i5 is welded or other wise suitably iastenedto the lower iii-metallic strip i, anciis sealed in the glass bulb B with its outer end exposed to the atmosphere. It is contemplated that after assembly and test or the device, the area of the member to exposed to the external air may be changed by cutting it ed to v25 diilerent lengths; and in this way'the rate of disnpation 01' heat irom the strip i may be var» led to obtain the desired adjustment in operat ing time. This construction may be used with evacuated bulbs, as well as gas ?lled bulbs. Fig. 3 illustrates a. modi?cation in the struc ture of the heat dissipating member 951, whichis bent or shaped at its outer end tor the attach» ment by a screw or the like of radiating disc or piece M2, the size and area of which can be se lected to give the desired exposure and radia tion to the atmosphere. The speci?c embodiments of the invention shown are merely illustrative; and various adap 3. A thermally operated circuit controller com prising a bi-metallic strip within an enclosing bulb, means for supplyingheat to said strip, heat conducting means connected to said strip and extending outside oi’ said bulb, said heat con ducting means being adapted to have its exposed area changed to vary the rate oi‘ dissipation of heat from said strip. ‘ 4. A thermally operated circuit controller com prising two bhmetallic strips mechanically con 10 nected and disposed to be deformed in opposite directions by a change in'the temperature of looth, means for heating one of said strips in dependently oi the other, contacts operated by the deformation 0! said heated strip, a gas-tight 15 bulb enclosing said strips and said contacts, and means changeable after assembly of the device, for varying the rate of dissipation oi" heat from the heated strip, said means for heating said strips being electrical heating means having con 20 nections extending outside of said bulb, whereby the time required to operate said contacts after application of current to said heating means can lie-regulated and be substantially constant irre spective of ambient temperatures. 5. A thermal circuit controlling devicecom prising, a bi-metallic strip, means for heating the strip, a closed ?exible gas ?lled chamber en closing the strip, and meansaccessible from the outside oi’ the chamber for varying the size of 30 the chamber and thus veil '13 the pressure of the gas therein, whereby to change the rate of dissipation 01' heat Irons the bi~metallic strip. 6. A thermal circuit controlling device com prising, a lei-metallic strip, means for heating the strip, a closed ?exible gas ?lled chamber en closing the strip, a closed rigid casing enclosing the chamber, and means accessible from the tstions, modi?cations, and additions may be made ' outside oi the casingj for varying the size of the to the speci?c constructions shown and de chamber and thus varying the pressure of the scribed, without departing vfrom the invention. has therein, whereby v"to change the rate of dis 40 ‘What I claim is:— ' slpation 0! heat from the bl-nietallic strip. l. A thermally operated circuit controlling de» ‘l’. A thermally operated circuit controller com vice comprising a lei-metallic thermal element prising a iii-metallic strip within an enclosing in an enclosing bulb, means for heating said ele hulls, means for supplying heat to said strip, heat ment, contacts operated ‘by deformation of said conducting means connected to said strip and element, and means for varying the rate oi’ dis~ extending outside of said bulb, said heat con sipation of heat from said element. . ducting means having receiving and fastening 2. A thermally operated circuit controliins ole means thereon for holding heat radiating mem vice of the character described, comprising it lol hers oi various radiating capacities, whereby to' metallic strip enclosed in E?hw?il‘id tube, and vary the rate of dissipation oi’ heat by said strip. 50 means adapted to be adjusted after assembly oi’ the device for varying the pressure of the has i'J?CAR S. FIELD. in said- tube, and thereby change the rate of iii-i slpation oi’ heat irom said bi=metallic strip.