Патент USA US2407362код для вставки
_ Sept. 10', 1946'. J. M. WILSON ' _ . 2,407,361 ' TEIIBERATURE MEASURIIG SYSTEM Filed July 2a, 1943 mm IN vsu ro/r JOHN M. wuson. ‘Patented Sept. 10,;1946 2,407,361 .‘UNl'l'ED STATES PATENT'OF-FICE TEMPERATURE MEASURING SYSTEM John M. Wilson, Minneapolis, Minn., assignor to Minneapolis-Honeywell Regulator Company, Minneapolis, Minn, a corporation or Delaware Application July 28, 1943, Serial No. 496,518' 11 Claims. (01. 177-311) 1 This invention relates to electrical signalling 2 Figure 4 is a plan view 01' a portion oi! a selector and controlling circuits for indicating or con switch utilized in the invention. trolling at a remote central point conditions pre vailing at a plurality of widely separated points, and more speci?cally to electrical signalling and control apparatus for remotely indicating the Throughout the drawing, corresponding nu merals indicate corresponding parts. Referring to the drawing, Figure 1 illustrates temperatures or other conditions prevailing at a is provided a resistance or impedance bridge gen erally‘designated l0 composed of a. plurality of plurality of separate bearings of machinery, loco ' the wiring diagram of the invention wherein there motives and the like. The invention has especial resistances or impedances II, l2, l3, l4, and ‘I5, utility for centrally indicating when the tempera 10 and any one or a plurality of resistance or im ture of any one of a plurality of bearings exceeds pedance elements 3l—-38. These elements will a maximum operating temperature, for example . hereinafter be referred to as resistance elements, when the wheel bearings 01 a locomotive reach or but it is to be understood that they may if desired exceed the permissible operating temperatures. be other types of impedance elements in certain ' It has been found in respect to Diesel and other 15 modes of application of the invention. locomotives that the rise in temperature beyond Resistance element H is connected between the permissible operating temperature is likely to junction l1 and junction IS, the latter being occur rapidly and that in order to prevent fail- ' grounded at 30. To junction I‘! there is connect ure of the bearings and possible disastrous re ed one terminal of resistance l2, which is pref- ' sults it is desirable to have a continuous check 20 erably made variable by means of tap IS, the tap on the temperature of the bearings. It is an object 01' the invention to provide a sig nalling and control apparatus for remotely in dicating at a central point the existence of an ab normal condition at any one of a plurality of sep arated points, it being a more particular object of the invention to provide a signalling and control apparatus for remotely indicating the tempera . ture of bearings of operating machinery. Partic ularly locomotives. It is a further object of the invention to provide a signalling and control system utilizing a. resist ance bridge wherein one element of the bridge is a l6 being connected by lead wire 22 to junction 23. From junction I‘! there extends a power input connection designated 24. Resistance element I3 is connected between junctions 23 and 25, the 25 latter junction being one of the bridge output terminals, the other bridge output‘ terminal being junction 58. Resistance element H is connected between junction 25 and junction 26, and to the latter there is connected a second power input connection 21. One terminal of resistance [5 is connected to junction 25 and, through a manually operated switch 28, to junction 28. ' Resistance elements ll, [2 plus l3 and I4 (or M remotely located resistance element located at the and IS in parallel) constitute three elements of a position where an operating condition is to be in 35 resistance bridge, the fourth element being any dicated and to utilize a change in the output volt one of the plurality of resistors 3| to 38, which age of said bridge for the operation of signalling may be located at selected remote points. The and control apparatus. ‘ remotely located resistors serve to indicate the It is a further obj ect of the invention to provide condition at the remote point, in accordance with r an apparatus for successively and sequentially 40 the system of the present invention. In the illus connecting: resistance elements in a resistance trated embodiment of the invention provision is bridge circuit and to utilize the bridge output for preferably made for sequentially and successively controlling the operation of signalling and con connecting said resistances 3| to 38 into the bridge trol apparatus. circuit, although the resistances may be connected Other objects of the invention will appear as 45 at random, if desired. It will be understood, of the description proceeds and will be found in the course, that there may be utilized a lesser or appended claims. greater number of resistances 3l-38 depending The invention is illustrated with reference to upon the number of remote points, the conditions the drawing in which, at which it is desired to be indicated by the ap Figure 1 is a wiring diagram of the apparatus; . 50 paratus'. Figure 2 is a schematic view illustrating the One end of each ‘of resistances 3 l—l8 is method of installation in respect to locomotive connected to a common ground wire '39, the latter wheel bearings; _ being conveniently grounded to the frame of the Figure 3 is an elevational view illustrating the machine or other suitable connection at 40. mode of installation of a typical responsive ele 55 Where it is desired to utilize the invention ‘for ment in the wheel bearing of a locomotive, and indicating temperatures the resistances 31-38 2,407,361 3 may be constructed of a material having a high coefficient of resistance so that as the ‘temperature varies at the point of installation of any one of the resistances 31-38, a corresponding variation will occur in the ohmic or impedance value of the resistance. It will of course be appreciated‘ that the resistance elements 3 |--38 may be made responsive to any desired function such as pres sure, humidity, gas analysis, or the like by utiliz a voltage and is communicated to the system by means of supply lines I00 and I0 I. A main switch .is provided at N12 for shutting down the system whenever desired. Lines I00 and I0| are con nected through junctions I04 and I05 to the motor ,IIO of a motor generator set generally designated H2. The generator indicated at I|3 supplies alternating current at an appropriate voltage to supply lines I I4 and H5, extending to ing a suitable responsive element coupled to the 10 the primary winding I20 of an alternating cur rent transformer generally designated I25. resistance (or impedance) element. The other ends of the resistances 3I-'-38 are 4 connected by lead wires 4I-48, respectively, to a plurality of contacts 5I—-58 of a sequence switch generally designated 60. The sequence switch may be of any suitable design and is provided with a movable contact (or cam) arrangement The transformer I25 is provided with a second ary winding I26 terminating in taps 24 and 21, these being connected to the correspondingly numbered lines of the resistance bridge by suit able connections not shown in the drawing. It will thus be observed that the transformer sec 6| for establishing fconnection successively and sequentially with contacts 5|-—58. The movable ondary I26 provides alternating current potential circle of contacts 5I-—58 there is arranged a through resistance II, junction I8, ground 20, to ground 40 (of resistances 3I-38),, thence across the bridge terminals junctions l1 and 26 contact 6| is connected through contact 65 20 and current‘ accordingly flows in the bridge through two parallel circuits as follows: (Figure 4) and thru lead wire 62 to junction 26 The ?rst of the parallel bridge circuits is from of the bridge. Since junction I8, and each of the transformer secondary-I26 via line 24 to junc resistances 3I—-38, are grounded the successive tion I1, and through bridge resistance I2, vari engagement of movable contact 6| with each of able tap I6, line 22, junction 23, resistance I3, the stationary contacts 5l-58 will cause resist junction 25,-and then through resistance I4 (or ances 3I-—38 to be connected successively across during testing, through resistance I4 in parallel the terminals l6 and 26 of the bridge, thus com with resistance I5 and switch 28), to‘ junction pleting the bridge circuit. , 26 and thence through line 21 to the transformer A suitable and desirable form of sequence switch is illustrated in Figure 4, wherein the con 30 secondary I26. The second of the parallel bridge circuits is from the transformer secondary I26 tacts 5|-—58 are shown as arranged in a circle through line 24 to junction I1 and thence as a plurality of arcuate segments. Within the a second circle of contacts 1|-18 for a purpose to be explained, and there is positioned a central 35 through any one of the resistance elements 3|3B (and its corresponding line 4|-—48) to ‘the solid, circular contact 65 which is fastened in corresponding terminals 5I—58, thence through place by suitable rivets or screws 66. The entire the sequence switch elements 6| and continuous arrangement may, if desired be madev by utilizing a plastic insulating ‘base 61 into which there is ' contact 65 to line 62, then to junction 26, and ?rst molded the central contact 65 and two solid 40 through line 21 to the corresponding terminal 21 circular rings of ‘contact material, which are later cut into segments so as to form the contacts of the transformer secondary I26. Alternating current thus flows through the resistance ele ments of the bridge and an electrical potential 5I-58 iii-an outer circle and contacts 1|-—_18 in difference is established between junction I8 and the intermediate circle. At the center of the in sulating block 61 there extends a shaft 80 upon 45 25 depending upon the relative sizes of the re sistance elements constituting the bridge. which there is mounted an ‘insulated arm BI The resistance constituting the bridge circuits carrying on its underside the resiliently mounted are chosen of such values that normally a pre bridge contact 6| illustrated in Figure 1. Thus determined voltage relation is established be as the shaft 80 rotates it carries with it arm Ill tween junctions I8 and 25. When the magni .and consequently causes the bridge contact 6| tude of a particular resistance 3|—38 of the successively to establish circuit between the cen bridge circuit is increased, due to any causative tral continuous contact 65 and the contacts 5| factor, the proportionality of the bridge will be and H or 52} and 12 etc. The shaft is caused to disturbed such that the voltage across junctions rotate continuously. The central contact ring 65 I8 and 25 is reduced, and as the value of re-‘ is connected to wire 62 and in effect serves as a ' sistance element 3I-—3Il increases still farther, continuous connection to the bridge contact 6 I, as the voltage across junctions I8 and 25 is further illustrated in Figure 1. reduced. For the rotation of shaft 80 there is provided The transformer I25 is‘ provided with another a motor generally designated 90, having a rotor BI and stationary windings 92 and 93. The rotor 60 secondary I21 terminating at taps 21 and I28, the latter being connected through relay contact is mounted on shaft 80, illustrated by dotted lines 220-A and line I29 to junction I30 on bus bar in Figure 1. The shaft, as previously mentioned, It“. The bus bar I3I serves as a common con carries the arm BI, and the latter in turn carries nection for a plurality of signal lamps I4I-—|48, the resiliently mounted sequence switch 6|. A there being one signal lamp for each resistance suitable gearing may be interposed between the 3|-38. The opposite terminals of the signal motor 90 and shaft 80 so as to permit either a lamps are connected, respectively, to contacts slow or rapid operation of the shaft 80 and arm 1I-—18 of the sequence switch 60. It will thus 8|, as desired. For indicating the temperature of bearings of a locomotive or similar large piece of ‘ be observed that a circuit is established begin machine'it is usually sufficient to cause complete 70 ning at tap 21 on transformer secondary wind ing I 21, through a line (not illustrated) to the rotation of shaft to and arm 8| every 1 or 2 minutes, thus providing, as hereinafter explained, . corresponding tap 21 of resistance bridge I 0, thence through line 62, contacts 65 and 6| to a complete check, every 1 or 2 minutes. any one of the contacts “~18, of the sequence The power supply for the system may be either direct or alternating current of any available 75 switch, thence through any one of the signal ‘1 2,407,801 lamps Ill-I09, bus bar I3I, junction I39, line gized. As a result, contact 2I8-A of relay 2I6 is I29, relays contact 220-A (which is normally open but closed under signalling conditions) and . normally open. The relay contact 2I6—A is in a circuit extending from junction I 04 on power sup line I29 to the opposite terminal of the trans ply line I00 through branch I06. relay contact former secondary winding I21. It will thus be] bl 2I6-—A, the coil 220 of a second relay and through observed that'as the sequence switch 60 is ro-, branch I01 to junction I05 of supply line IOI. tated potential circuits are established to signal Thus when relay 2I6 is energized, as occurs when‘ lamps Ill-443 and the lamps will be illumini _ resistances 3I—39 are abnormally high, contact ated provided contact of relay 220--A happens 2I8-A closes and establishes a circuit through 10 the coil of relay winding 220. to be closed. ‘ _ The transformer I25 is provided with another’ Relay 220 is provided with three contacts secondary winding I32 having secondary ter , 220-A, 220-B and 220—-C. Contact 220—A is in mine] lead wires I33, I36, and I35, line I34 being ‘ the circuit of signal lamps Ill-I49 and illumi grounded at I36. The portion of secondary I32 ‘ ‘ hates one or another of these lamps when'relay between lead wires I30 and I35 serves as the in 220 is energized, and hence closes contact 220-A. put to a recti?er tube I50 having a cathode I5I, Contact 220-B is normally closed (when relay heating ?lament I52, a control grid I53 and plate I56, the control grid I53 and cathode I5I ’ being connected together. ’ The cathode heater ?lament I52 is connected in series with the heat er ?laments of other tubes, by circuits not com pletely illustrated, all as hereinafter explained. The rectifier tube I50 serves to supply a half wave- recti?ed current to line I56 connected to .coil 220 is deenergized) and establishes a circuit to motor 90 as follows: A ?rst motor circuit at junction ill on the feeder II5 of generator II3, 20 the circuit extending through normally closed ' relay contact 220-B, connection II9 to junction I2 I, thence through winding 93, line I22, junction I23, line, I31 to junction III on feeder I“, of cathode I5I. Line I56 extends through junction _ I51 to‘ one terminal of a'?lter inductance I59. Both terminals of the ?lter inductance I59 are from feeder II5, through junction II1, line II8, normally closed contact 220-43 of relay 220, line H9, junction I2I, through line I38, junction I39, connected through condensers to ground, there being two condensers I60 and I6I connected as indicated. The ?lter arrangement serves to smooth out the direct current potential applied line I30, through a phase-shifting condenser I49, line I55, thence through winding 92 and line I22 to junction I23, and through line I31 to junction III on feeder III. Accordingly, so long as relay 220 is de-energized, its contact .220—B remains closed and windings 92 and 93 are energized. When relay H6 is energized,- its contact 2I6—A is closed, relay 220 becomes energized, opens contact to line I65 extending through resistor‘ I66 to junction I61 of line I10. generator II3. A second parallel circuit extent-is . From junctions I9 and-25, which are the out put terminals'of bridge I0, there extend lines I62 and I63 connected to the terminals of po tentiometer resistance I66 of relatively high 220-B and interrupts the circuits to motor 90 thus stopping the sequence switch. The con ohmic value. From variable tap I88 on re denser I99 serves to shift the phase of the cur sistance I69 there extends a lead I69 connect rent ?owing through winding 92 of motor 90 and ing through capacitor IN to junction I12 and 40 accordingly there is provided the necessary ro thence through'line I13 to the grid I83 of an tating ?eld requisite to the operation of a squir ampli?er tube, generally designated I80. The rel-cage rotor I0’ of motor 90. ampli?er tube I80 is provided with a cathode I38I, indirectly heated by ?lament I92, and is provided with‘ a plate I94 connected to line I10. From cathode I8I there extends lead wire I95 I > All of the heating ?laments of the several tubes, viz.,recti?er tube I50 and ampli?er tubes I90 45 and 2I0 are connected in a series circuit extend ing from power supply line IOI through branch ' connecting, at junction I96, to resistor I81 and I 01, thence through line I16 through pairs of capacitance I90,‘both of these being grounded terminals I15, I16, I11, in series, which are con at I98. Grounded line I92 is connected to one nected to the three ?laments of the three tubes, terminal of a resistor I93, the opposite terminal 50 thence through a pilot light I 18 and voltage lim of the resistor being connected to junction I12 iting resistor I 19 and lines I89 and I06 to terminal of the grid connection I13. ' I00 on power supply line I00. If desired aby Junction I81 in the plate circuit I10 constitutes pass resistor I18’ may be included in parallel the output of the ampli?er tube I90 and is con with pilot lamp I18 so that a standard ?lament nected through capacitance I95 which is in turn lamp may be used in the circuit and at the same connected through line I96 to the grid 2 I3 of sec time suf?cient current drawn to permit suitable > 0nd stage ampli?er tube, generally designated 2 I 0. heating of the ?laments of the tubes. It will be From junction I91 on grid connection I96 there understood that the terminals I15 are connected extends a resistor I98 which is grounded by line to the ‘?lament leads of recti?er tube I50, that the I99. A capacitance 20I parallels resistor I99, be pair of terminals I16 are connected to the ?la ing connected to line I96 at junction 200, and ment leads of ampli?er tube I80, and that the grounded.v through line 202 to junction 203 on terminals of ampli?er I11 are connected to the ground line I99. The ampli?er tube 2I0 is pro ?lament leads of ampli?er tube 2I0. According vided with a cathode 2II, indirectly heated by, ly, whenever switch I02 is closed current will ?ow ?lament 212, and is also provided with a plate, 65 from line IOI through I 01, thence through the 2“ connected through line. 2| 5 to one terminal of ?laments I52 of rectifier tube I50, ?lament I 82 a relay coil 2 I6, the opposite terminal of the relay of ampli?er tube I80, and ?lament 2I2 of ampli being connected through line I33 to winding I32 ?er tube 2I0 and thence through line I10 and on the transformer ‘I25. A condenser 2I6' is pilot light I18, resistor I 19, lines I89 and I06 to connected in parallel with the relay coil 2I6. 70 line I00. Resistor I19 is likewise used in series Relay 2I6 is provided with a single operated with the ?laments, in order that standard volt contact 2 I 6-—A which is closed when the relay 2 I 6 age ?laments may be used. Obviously, the use of is energized. When resistances 3l—38 are of special ?laments or tubes I50, I 80, 2I0 and in normal value, tubes I80 and 2I0 are not conduc lamp I18, would obviate-the need for resistances ‘ tive and relay 2I6 is therefore normally deener 75 I19’ and I19. 2,407,861 O In parallel with contacts 220-B of relay 220 there is provided a manually operated switch 228 which is mechanically coupled to switch .28 in motor-generator set designated II2. A circuit is also established through the pilot light I18 and through the heating ?laments of the rectifier and circuit with resistance] 5 of the resistance bridge, so that switches 28 and 228 are closed simulj ampli?er tubes as heretofore described. The gen taneously for testing‘ the system, as hereinafter ‘appropriate voltage to the primary I20 of the erator H3 provides alternating current of an transformer I25 and by means of secondary I28, voltage is impressed across terminals I1 and 28 of the resistance bridge. The resistances are ' energized, this switch being in a circuit extending 10 proportioned so that when resistances 8I~—88 have a normal_temperature and hence normal from junction I08 on supply line I00 through explained. ' - 8 Relay 220 is also provided with a contact 220-C which is closed when relay 220 is de ohmic value, the voltage across potentiometer I80 will yield an appropriate voltage on grid I83 of ampli?er tube I80, and under such condition the Normally energized relay coil 223 holds switch 223-A open and switch 223-B closed. Switch 15 ampli?er tubes I80 and 2I0 are not conductive. As a result relay 2I6 is not energized and contact 223--B may control the locomotive so as to stop it 2I6-A remains open. upon opening of such switch while switch 223--A Relay 220 is controlled by contact 2I8-—A of may operate a signal upon closing of such switch. relay 2H; and is accordingly tie-energized and Referring to Figure 3 there is illustrated the manner in which the individual resistance ele 20 maintains its contact 220—A open and contacts 220—0 and 220-B closed. Relay‘ coil 223 is ments 3I—38 may conveniently be mounted on a therefore energized, the locomotive may run and typical bearing. In Figure 3 connection 4i‘ (Fig the signal is not operating. As a result the alter ure 1) extends through a suitable conduit to the nating current supplied by generator H3 is ap resistance‘ element (one of the elements ill-38) which is preferably located in a metal container 25 plied from line II5 through contact 220-B of the twowindi'ngs 82 and 93 of the motor I0, thus 49. The container has an extending end portion causing the continuous operation of motor 90 and 50 and the entire resistance element in its hous consequent. continuous operation of switch 80. ing is inserted into the bearing block by means During the existence of this condition the signal of ,a suitable drilled and threaded or other me chanical connection. The resistance (3I-—38) is 30 lamps I4 I—I 48 are not illuminated, because their operating circuit is. interrupted by the open con electrically insulated from the metal housing 50, tact 220—A of relay 220. except that one of its terminals is grounded to The foregoingconditions continue until, due to the housing so as to complete the circuit of the increase of the temperature of one of the journals resistance element. The resistance is in com plete thermal contact with the bearing block 59, 35 the ohmic value of some one of resistances 3I—38 also increases. When this occurs, the voltage at the temperature of which is desired to be indi tap I68 changes. , Thus, for example, where the cated and registered by the apparatus of the resistances 3I—-38 are used to indicate bearing ' invention. .Figure 3 schematically illustrates a temperatures, so long as the temperature of each railroad locomotive wheel 82 mounted upon an bearing, remains below a predetermined value the axle 83 in the usual manner. The bearing block voltage applied to grid I83 is such as to prevent or “brass” 59 is positioned upon the axle in ac operative energization of relay coil 2I8. Upon cordance with standard practice. increase in bearing temperature and consequent In Figure 2 there is schematically illustrated increase in the ohmic value of its associated the manner in which the invention is applied to line 222, relay contact 220—C, a relay coil 223 and line 220 to junction I09 of power supply line IOI. a typical machine, for example a locomotive. In 45 resistance, the voltage applied to grid I83 ?nally becomes such that relay 2I6 is energized and Figure 2 there are illustrated four wheel and axle closes contact 2I6—A. This energizes relay 220. assemblies of a locomotive these being numbered As a result of the energization of relay 220 84, 85, 86, 81. In the actual locomotive the wheel contact 220——B is opened, thus interrupting the and axle assemblies are electrically connected together by the locomotive frame as indicated 50 circuit of motor 90, which accordingly stops quickly in a position such that contact 8| of‘ by the dotted line 88, and the frame is grounded selector switch 60 is on the particular contacts‘ at 40, this being in an electrical sense, the ground 5I‘—58 and 1I-18, corresponding to the offend 40 of Figure l. The journal blocks are indicated ing resistance*3l—38, the value of which had at 84', 84", 85', 85", 88’, 86", 81', 81" and each journal is provided with one of the resistance 55 been increased by an increase in the temperature 'of its bearing. With the motor 80' stopped and elements 3I through 38 of Figure 1, these being relay 220 energized contact 220—A is closed, thus suitably attached as in Figure 3. It will be under establishing a circuit from winding I21 of the stood that one of the resistance elements 3I--38 transformer through line I28, then closed con is placed in each wheel bearing. ‘Obviously for locomotives or other machinery having a greater 60 ‘tact 220—A and bus bar Nil/through the par ticular pilot lamp I4I—I48 corresponding to the or lesser number of bearings, it is only necessary offending resistor 3I-—38 and its contact and to provide an equal number of resistance ele thence through contact SI of the selector switch ments of the type shown at 3I-38 in Figure l, and line 62 to terminal 21 of the bridge, which and in some instances several resistance elements may be used in. a very large journal, where a 65 is connected by a lead wire not illustrated to terminal 21 of the transformer secondary I21. temperature difference may exist between parts The pilot lamp corresponding to the offending of the journal. In all instances, of course, the resistor 3I--38 is accordingly lighted. At the selector switch 60 would have a number of con same time contact 220-C is opened and relay tacts equal to the number of resistance elements 223 is de-energized whereby the signal or control in the system. circuit is completed through switch 223--A> Operation In order to place the apparatus in' service switch I02 is closed (as shown) which accord ingly furnishes power to the motor II 0 of the 75 thereby performing the desired function in such circuit. The switch 223-3 may, as explained above, be used to stop the locomotive. ' In the event one of the resistors 3I—.38, 'or any 9,407,801 » portion or their respective circuits, becomes open circuited, this will in e?ect increase the value of the resistance or resistances 8l-88 t0 in?nite value, and the effect will be to stop motor Oil- and - illuminate the corresponding pilot lamp ill-I48, in the same manner as occurs when the value of the resistances 3l--38 is increased due to an increased temperature. Therefore such an open circuit condition is automatically indicated by » 10. it is obvious that it likewise has utility for indi cating conditions other than temperature as well as for control purposes. It is also clear that many changes may be made without departing from the spirit of my invention and I therefore intend vto be limited only by the scope of the claims ap pended hereto. I claim as my invention: 1. The combination comprising a plurality of separately located resistances each having a normal value. said resistancesbeing construct If any one of the resistances 3l—88 becomes short circuited or any other factors occur which ~ ' ed of ‘a material having an appreciable temper ature coemcient of resistance, a resistance bridge in effect lowers the resistance value of such por tions of the resistors or their circuits. this will ecircuit composed of a plurality of resistors and produce a further unbalance of the bridge in the 15 ‘said separately located resistances, sequence switch means for successively connecting said direction normally maintained, vand as a result Y remotely located resistances in said resistance the motor 90 and signal lamps will not automat bridge circuit including motor means for oper ically be operated, to indicate the .low resistance the apparatus. ' ' 10' fault. ‘1 In order to test for such low resistance or ating said sequence switch means, a power sup short-circuit types of faults, test switches 28 and 20 ply ior'said motor means, relay means for con trolling the connection 01' said motor means to 228 (which are connected together) are manu said power supply, an ampli?er having its input ally closed. Closure of switch 28 places resist connected to said resistance bridge circuit and ance i 5 in parallel with resistance It. The value its output connected to said relay means, said I of resistance It, is relatively low so that there sulting resistance of resistances i4 and IS in 25 ampli?er being adjusted so as to cause the op eration of said relay means to stop the motor parallel is su?iciently low that any unbroken or when the sequence switch driven by the motor has connected to ‘the bridge circuit one of the separately located resistances having an appre age to grid I83 at a normal journal bearing tem perature such as to indicate that the journal 30 ciably increased resistance, a plurality of sig nal' means, one corresponding to each separately bearing temperature is too hot. Stated in an located resistance, and a set of contacts in said other way, the effect of closing switch 28 is to sequence switch for successively connecting said _ lower the temperature setting of each of the re _ signal means in a suitable circuit. sistances 3| to 38 so that each of them, unless unshorted one of the resistances 3l—38, when connected in the ‘bridge circuit, will apply volt- short circuited, causes relay 2l6.to be energized 35 2. The combination comprising‘a plurality of separately located resistances each having a nor and the proper pilot light to be lighted. The si multaneous closing of switch 228 provides con stant energization for motor 90 so that it does _ mal value, said resistances being constructed of a material having an appreciable temperature not stop upon energization of relay 216. In this ’ coef?cient of resistance, a resistance bridge cir manner each of the resistances 3l-—38 may be 40 cuit composed of a plurality of resistors and said checked sequentially. If one of these resistances should be short circuited or its resistance is be low some predetermined value as dictated by the separately located resistances, sequence switch means for successively connecting said remotely located resistances in said resistance bridge cir value of resistance l5, then, the voltage impressed ' cuit including motor means for operating said on grid I83 will be of the same order as though such resistance were normal, the temperature was motor means, relay means for controlling the normal, and switch 28 was open. Such short cir ' cuited resistance will therefore fail to energize relay H6 and its associated pilot light will not become lighted thereby indicating the short cir cuit. Summing up then, upon a dangerous temper ature being established at any bearing of the locomotive, its associated resistance element has its resistance increased causing ‘the motor 80 to stop and an appropriate signal light indicating which bearing is overheated to be lighted. .At 1 the same time, through switch 220-0, relay 223, and switch 223--A an audible signal may be op-. ' erated. Switch 228-3 may be utilized to stop 'A burned out resistance will the locomotive. cause an increase in resistance just as a temper_ vature rise and the system thereby checks for a ‘ burned out resistance. In addition, the appa ratus maybe tested or checked by closing switches 28 vvand 228. In this checking operation ‘each pilot light will be' lighted provided its as sociated resistance has not been short‘ circuited below a predetermined resistance. Likewise, if the pilot light itself should be burned out, it will , not light and will be an indication that there ‘has been a failure of some type in the system. While the present. invention has particular‘ ‘utility in checking successively the temperatures sequence switch means, .a power supply for said connection of said motor means to said power supply, an ampli?er having its input connected to said resistance bridge circuit and its output connected to'vsaid relay means, said ampli?er being adjusted so as to cause the operation of - said relay means to stop the motor when the sequence switch driven by the motor has con nected to the bridge circuit one of the sepa rately located resistances having an appreciably increased resistance, a plurality oi'signal devices, one corresponding to each separately located re sistance, a set of contacts on said selector switch, there being one contact for each signal device for preparing a circuit therethrough, and means op erable coincidental with the stopping of said sequence switch drive motor for completing said signal device circuit. ' 3. In a measuring apparatus, a plurality of‘ measuring devices for measuring an undesirable _ condition, a mechanism to be actuated thereby upon the occurrence 01' an undesirable condition, means for recurrently connecting and discon necting each of said devices to said mechanism_ to cause actuation of said mechanism upon the occurrence of an undesirable condition at any one of said devices, and means associated with said devices and mechanism for effectively lower ing the value of said undesirable condition'ior of'bearings in a locomotive or other railway car, 75 causing actuation of said mechanism by each 2,407,861 11 12 of said devices even though an actual undesir having a pair of contacts for each of said resis tors, each of said resistors being connected to one contact of each of said pairs, the other con tact of each of said pairs being connected to an able condition does not exist, whereby the op erativeness of said measuring apparatus may be checked. ' 4. Inv combination, an electrical apparatus. adapted to be operated when connected to a pre determined electrical resistance value, a resist ' individual signal means, said switch means in cluding a contactor driven by the switch motor and engaging said contacts a pair at a, time, said switch means being capable of sequentially plac ance means connected to said apparatus and normally having a, value other than said prede ing said resistors into and out of said network termined value, a test resistance, and means for 10 so that said bridge network is sequentially com connecting said test resistance to said resistance pleted by each of said resistors, means supplying .means, said test resistance having such value input current to said network, said network, when completed by a resistor, giving an electrical out that the resistance means and test resistance together subject said electrical apparatus to said put indicative of the resistance of said resistor, predetermined resistance value to operate the 15 means for amplifying said output, relay means controlled by said ampli?ed output, second'sig same when said resistance means is at said nor mal value, but do not subject said electrical ap nal means, and means controlling the movement of the vehicle, said relay means, when actuated by an ampli?ed output current of predetermined lower than said normal value. 20 value, energizing said individual signal means, deenergizing said motor, energizing said second 5. In a device of the character described, in ' paratus to said predetermined resistance value if said resistance means is at a value considerably signal means and decreasing the movement of. combination, a motor driven switch means hav the vehicle. _ ing a plurality of pairs of contacts and a con 8. In temperature 7 indicating, apparatus, in tactor sequentially movable over said contacts a pair at a time, one contact of each of said pairs 25 combination, a plurality of temperature respon being arranged for connection to a remote tem sive electrical means, electrical indicating means, power driven switch means for sequentially con perature responsive impedance, said contactor necting said temperature responsive means in op being connected to means capable of giving an erative relation to said indicating means, said in electrical response indicative of the impedance value of each impedance connected to said switch 30 dicating means being capable of responding to a predetermined temperature at any one of said‘ means, means for amplifying such a response, re temperature responsive means in a given manner, lay means capable of actuation when said ampli and test means for electrically modifying said in fled response is of a predetermined value, and a dicating means so that said indicating means will plurality of signal means, the other contacts of each of said pairs being individually connected to respond in said given manner when the tempera said signal means, said relay controlling the en ergization of the motor of said motor driven ture at said one ‘means is at a normal value dif ferent from said predetermined temperature. 9. In an indicating apparatus arranged to be connected to‘a plurality of temperature respon . of said signal means in such manner that, upon anindication of an unduly high impedance value, 40 sive resistors having substantially similar char acteristics comprising, in combination, an incom the motor driven switch is stopped and a signal plete electrical network, motor driven switch means is energized to indicate on which pair of means for sequentially connecting said resistors contacts the contactor has stopped. into said network, electrical means responsive to 6. In a device of the character described, in combination, a motor driven switch means hav 45 the degree of balance of said network for stop‘ ping the operation of said motor driven switch‘ ing a plurality of pairs of contacts and a con means and providing a given indication when a tactor sequentially movable over said contacts switch means and the energizing means for each a pair at a time, one contact of each of said resistor'responding to an abnormal temperature ' pairs being arranged for connection to a remote is connected into said network, and manually op- , temperature responsive impedance, said contac 50 erated testing means including a circuit for alter ing the balance of said network so that said given indication will result from the connection into the network of a resistor responding to a lower tem perature, said testing means also causing oper switch means, means for amplifying such a re— sponse, relay means capable of actuation when 55 ation of said motor driven switch means. said ampli?ed response is of a predetermined 10. A railway vehicle having a plurality of value, a plurality of signal means, the other con journal bearings, a temperature responsive re tacts of each of said pairs being individually sistance unit mounted in close thermal communi connected to visual signal means, and an audible cation with each bearing, a plural element par signal means, said relay controlling the energi 60 tially completed electrical'network circuit, a mo zation of the motor of said motor driven switch tor driven sequence switch for successively con and the energizing means for said signal means necting said resistance units to the network cir in such manner that, upon an indication of an cuit to complete said. circuit, relay means, an unduly high impedance value, the motor driven ampli?er means having its input connected to the switch‘ is stQDped, ‘the visual signal means is en network circuit and its output connected to said ergized to indicate on which pair of contacts the relay means, signal means corresponding to each contactor has stopped and the audible signal resistance unit, contact means operated by said means is sounded. sequence switch for preparing a circuit to the sig '1. In a journal bearing alarm system for 3, ve nal means corresponding to a particular resist hicle having a plurality of journal bearings, a tor being connected to means capable of giving an electrical response indicative of the imped ance value of each impedance connectedto said temperature sensitive resistor means associated with each of said bearings and responsive to the temperature of same, a partial electrical bridge network capable of being completed by any one of said resistors, a motor driven sequence switch 75 ance unit when said unit is connected to said network by said sequence switch, said relay means interrupting the circuit to said‘ sequence switch motor and completing the circuit to said signal means when the said unit connected into said 2,407,881 13 14 network circuit has a resistance indicative of a a plurality of signal means, the other one or each relative high temperature; of said pairs of switching means being individu- _ 11. In a device of the character described, in combination, a plurality of switching ,means, means including a motor for operating said switching means in sequence a pair at a time, one ally connected to said signal means, said relay means controlling the energization Of the motor of said motor operated switching means and the energizing means for each of said signal means in of ‘each of said pairs being arranged for connect such manner that, upon an indication of an un v _ ing a remote temperature responsive impedance duly high impedance value, the motor operated to means capable of giving an electrical response indicative of the impedance value of the said im pedance, means for amplifying such a response, relay means capable oi.’ actuation‘ when said am switching means is stopped and a signal means pliiied response is of a predetermined value, and is energized to indicate at which pair the switch ing, means has stopped. , JOHN M; WILSON.