Патент USA US2412881код для вставки
Dec. 17, 1946. w_ <;_ FULTON ' CONTROL 2,412,881 SYSTEM ‘ Filed Sept. _1'4, 1944 ' ~24 _' E », ‘9-6 i" Temper-a fur: Ee/ay. 'I- Temperafure fnd/ca/‘a/T WITNESSES! £4 m Jr .21- ‘ INVENTOR ‘ ' Wilbur c. Fla/fan." . B M4 ATTOR i?Y 9 / ‘Patented Dec. 17, 1946 I . 2,412,881: UNITED ‘ STATES 7 PATENT‘ OFFICE j 2,412,881 con'rnor. SYSTEM Wilbur C. Fulton, Wilkinsburg, Pa., assignor to Westinghouse Electric Corporation, East Pitts burgh, Pa., a corporation of Pennsylvania Application September 14, 194,4, Serial No. 554,113‘ 4 Claims. ’ (Cl. 177-311) 1 - My invention relates, generally, to control sys tems, and it has reference in particular to tem perature indicator and temperature responsive control systems. . Generally stated, it is an object of my inven tion to provide a combination temperature indi 2 conductors l3. Closure of the circuit breaker l2 may be effected by operating means represented . by the push~button switch l5 which provides for connecting the operating winding l6 0! the cir-' ‘ cuit breaker to a suitable source of control po- * cator, alarm, and protective control system tential. The circuit breaker may be opened. by means of a trip winding ll associated with the which is simple and inexpensive to manufacture circuit breaker latch means it. .and which is easy to operate. i ‘ > In order to provide an indication of the op _ More specifically, it is an object of my inven 10 erating temperature of the apparatus Ill, and operate an alarm 20 when the temperature tion to provide for using a single temperature reaches a predetermined level, as well as effect detector coil for operating a temperature indi shut down of the_apparatus when the’tempera cator, an alarm, and performing a control func-. ' ture reaches a still higher predetermined value, tion. It is also an object of my invention to provide 15 means such as the temperature detector coil 22 for selectively connecting a single temperature may be provided. The [coil 22 may be positioned indicator coil to a temperature indicator, or to alarm and. control circuits. in any suitable location on the apparatus in a manner well known in the art. With a view to e?ectingoperation of the alarm Another object of my invention is to provide for normally connecting a temperature indicator 20 20 and of a control relay 23 for deenergizing the apparatus i0, temperature responsive control coil for sequentially operating an alarm and a . means 24 may be provided. The control means control relay for deenergizing apparatus; and to provide for'selectively connecting the coil to a may comprise a temperature responsive relay ‘ 25 having a stationary ?eld structure 26 with a temperature indicator device. ‘ Yet anotherobject of my invention is to pro 25 ?eld winding 21, which may be energized from a source such as the rectifier bridge circuit 28 vide for using a single temperature detector coil connected to a control winding 29 of a suitable to perform a plurality of di?erent functions. control transformer 30 connected to the con A further object of my invention is to provide ductors, 13. The relay 25 may also be provided for sequentially performing a plurality of dif with a movable winding 32 which may be con ferent functions with a single temperature de-v tector device.‘ . ' , nected in a Wheatstone bridge circuit .in con- ,. - junction with control resistors 34, 35, 36, the temperature detector 'coil 22, and the recti?er Other objects will in part be obvious, and ‘will in part be described hereinafter. _‘ bridge circuit 28. The movable winding 32 may In practicing my invention a single tempera ture detector coil may be used for both measuring 35 be operatively connected to a movable contact arm 38 movable between - stationary ‘contact the temperature of a piece of apparatus and per members 39 and 40. A spring 4| may be pro forming a plurality of other functions in con vided for normally biasing the contact arm 38 nection th'erewith.- A, control switch normally into engagement with the stationary contact connects the temperature detector coil to a tem Q perature responsive relay which effects opera 40 member 39. The energization of the alarm 20 may be con tion of an alarm when a predetermined tempera trolled by a normally energized control relay 42 ture is reached, and e?ects operation of a control having an operating winding 43 which may be relay when a predetermined highertemperature ‘normally energized through a circuit extending is reached to shut down the apparatus. The through the contact arm 38 ‘and stationary con control switch may be operated to'connect the tact member 39 of the temperature responsive detector to a'temperature indicator whenever an relay. Deenergization of the control relay 42 indication of'the actual temperature of the ap- . through the opening of contact members 318 and paratus is desired. 39 effects energization of the alarm 20 through ‘ For amore complete understanding of the na ture and scope of my invention reference may be 50 contact members 42a of the control relay. As the temperature of the apparatus l0 in ' made to the following detailed description, which creases the contact arm 38 continues to move in may be read in connection with the accompany ing drawing, in which the single ?gure is a di agrammatic view of a control system embodying the invention in one of its forms. Referring to the single ?gure of the drawing, the reference numeral in may denote a piece of electrically operated apparatus which may be 55 the counterclockwise direction against the spring 4|. When the temperature of_the apparatus l0. reaches a higher predetermined value, the moving contact arm 38 engages the upper stationary con tact member 40. ‘An energizing circuit for the control relay 23 is thereby established from the negative terminal of the source through contact ' connected by means of a circuit breaker l2 to a source of electrical energy represented by the 60 arm 38, stationary contact member 40 operating 2,412,881 4 use with apparatus comprising, a‘temperature de Winding"v and contact members In of the cir cuit breaker for operating the control relay 23. A holding. circuit ‘for the control relay 23 is pro _ tector coil associated with the apparatus, a tem perature re'sponsive‘relay having an operating ' winding connected for energization in accordance . vided through contact members 23b and at the with the temperature of the detector coil and pro vided with normally closed contact means and > same time an energizing circuit for the trip wind ing I1 is provided through contact members 23a so that the circuit breaker is tripped and the 941- w ~normally open contact means actuable in se quence in accordance with the energization of said winding,_ alarm means operable under the If it is desired to obtain an actual temperature 10 control of the normally closed contact means'of indication of the apparatus 10 at any time during the temperature responsive relay when the ap operation,- a temperature indicator 4'! maybe pro-3 _ paratus reaches a predetermined operating tem I vided. This indicator may comprise a tempera-.v perature, and relay means operable under the ture indicator device 48' disposed to be connected control of the normally open contact means of in a-Wheatstone bridge relation with control re 15 the temperature responsive relay when the appa paratus I0 is disconnected from the conductors‘ I8. . ratusreaches a'higher predetermined operating temperature to render the apparatus inoperative.‘ sistors 49, 50, ‘and 5|, the temperature detector coil .22, and a source such as the recti?er bridge circuit 52 which may be energized from a winding -2. The combination with a single temperature j detector coil, of a bridge circuit including a tem perature responsive relay, 9. bridge indicating cir 53 of the control transformer 30. Inorder to effect a transfer from the tempera ture responsive relay 25 to the temperature indi cuit including a temperature indicator device, cator device 48, a transfer switch 54 may be pro and a control switch operable to connect the de vided. The transfer switch may be normally dis posed to connect the moving coil 32 of the tem . tector coil in one leg of either the temperature re sponsive relay or the temperature indicator device perature responsive relay 25 in the Wheatstone 25 bridge circuit, said control switch having means bridge circuit of the temperature responsive means 24 through movable contact members 55 ‘ and '56 in one operating position, to which-it may for biasing it to normally connect the detector coil in the temperature responsive relay bridge - circuit. be biased by a. spring 51. In the other operating 3. In a control system for-‘electrically operated position the temperature detector vcoil ~22v may be 30 apparatus, a temperature detector coil associated connected to form one leg of the Wheatstone bridge circuit inwhich the temperature indicator . device 48 is connected. with the apparatus and electrically disconnected ‘from its main circuit, a temperature relay having i a moving coil connected to the detector coil and In' order to prevent a vfalse operation. of: the '-~' having normally closed contacts which open when temperature responsive relay 25 when making the 35 the apparatus reaches-a predetermined tempera ture and normally open contacts which close arranged to, disengage its associated stationary when‘ the apparatus reaches a predetermined ' transfer, the moving contact member 55 may be contact members before the moving contact mem- - ber 56. \In this manner the Wheatstone bridge including a relaynormally energized through the circuit including the moving winding of the tem 40 normally closed contacts of the temperature relay. perature responsive relay is de?nitely discon and operable when deenergized to energize the nected from the recti?er bridge circuit 28, and the alarm means, switch means controlling the en , leg of the Wheatstone bridge circuit containing ‘ the resistor 36 is opened' before the temperature ~ .- , . From the above description and the accom panying drawing it will be apparent that I have provided a simple'and inexpensive control circuit for obtaining a plurality of operating functions in conjunction with ‘a single temperature detector coil. The apparatus involved is simple and in expensive to manufacture and provides a reliable and economical temperature indicator as well as ‘protective control system for protectihg'apparatus against damage due to excessive temperatures. .Since certain changes may be made in the above i - ergization of the apparatus,v and additional con detector coil is disconnected from the Wheatstone 45 bridge circuit. Any tendency of the temperature responsive relay to operate and give a false indi-. cation of increased temperature because of open ing the leg of the Wheatstone bridge circuit in vwhich the coil-22 is connected is thereby pre 50 vented. ' ‘higher temperature, alarm means, control means trol means disposed to be energized through the normally open ‘contacts of the temperature re lay for e?ecting operation of the switch means. 4. For use with aisingle temperature detector I coil associated with a- piece of apparatus, a tem perature indicator, a thermal relay having a mov able contact arm and a moving coil for actuating \ the movable contact’arm to di?erent operating. at positions,'means ‘for applying direct current po tentials ~to the detector coil and the thermal re lay moving coil or temperature indicator selec tively including switch means having normally closed contact members and normally open con tact members, circuit means including theno'r mally closed contact members connecting the de- ‘ tector coil and the moving coil in a Wheatstone bridge circuit with one of, said direct current con trol potentials, additional circuit means including the normally‘ open contact members "operable to connect the detectorcoil andlthe temperature in ‘of thelinvention may be made without departing dicator ma Wheatstone bridge circuit with an from the spirit and scope thereof, it is intended 85 other of the substantially; constant control ‘po described construction and different embodiments ' that all or the’ matter contained in the above de scription and shown in the accompanying drawing ' tentials, the normally (closed. contact members be-'- , ing arranged to disconnect the Wheatstone bridge shall be considered as illustrative and not in a " -' circuit from the-source before limiting sense. ' , . Iclaim as my invention: ‘ ' ' ' 7 31o .erations - 1_. A temperature responsive control system for disconnecting-the ' detector coil therefrom, so as to prevent false op.- -' or the ‘relay. ' wiLBuRc. FULTON.