Патент USA US2128578код для вставки
Aug. 30, 1938. ' 2,128,578 (F. R. BRIDGES SIGNALING SYSTEM ,Filed Dec. 24, 1955 l t . ‘ Z/it: ‘gig! IJ/QI v . ' . , ' 2 Sheets-Sheet 2 H -, ,?zzlerzior jé‘arzi'??riges - ?iljs. Patented Aug. 30, 1938 2,128,578 UlTED STATES PATENT OFFEQE 2,128,578 SIGNALING SYSTEM Frank R. Bridges, Needham, Mass, assignor to The Gamewell Company, Newton Upper Falls, Mass, a corporation of Massachusetts Application December 24, 1935, Serial No. 56,044 7 Claims. (01. 177-378) This invention relates to signaling systems and more particularly to fire alarm and similar sys tems, which, as is well known, require provisions for reliable operation even under extremely ad verse conditions as, for example, broken, grounded, or short circuited lines. Such provisions include in most cases the use of an emergency conductor. which is under certain conditions supplied with current impulses derived from the source normally supplying the signaling circuit with current. The present invention also utilizes a separate con ductor, usually the ground, for emergency signal ing, but provides improvements which render the operation of signaling systems of this type especi ally secure and certain. The principal object of my invention is to pro vide a comparatively simple, rugged and there fore reliable, durable and inexpensive signal trans mitting station or alarm box which is neverthe 20 less adapted to perform the functions of more complicated devices for signaling under abnor mal conditions through an emergency conductor, especially in circuits according to my Patent No. 2,056,709 of October 6, 1936, although it is under 25 stood that the new apparatus will provide these bene?cial and novel functions in other installa tions. Other objects and aspects of my invention will be apparent from the following description, by .30 way of example, of a speci?c embodiment of the invention. in which: This description refers to drawings, Fig. 1 represents a connection diagram of a signaling circuit including a sender according to v35 the present invention; _ Fig. 2 a side elevation of the contact and non interference magnet portion of an alarm box in corporating my invention; Fig. 3 is a schematical side elevation of the con .40 tacts of Fig. 2, showing the contact side by side instead of behind each other; Fig. 4 is a detail View of- the contact control mechanism shown in Figs. 2 and 3; Fig. 5 a schematical representation of the .45 spatial contact arrangement according to- Fig. 2; and Fig. 6 a schematical representation of a modi ?ed contact control arrangement. Referring to Fig. l, L denotes a signal line or :50 loop leading to station terminals I and 2 and containing a number of signal transmitters, here in referred to as alarm boxes R, R’, R” which normally keep the signal loop closed and their ground connections open. Busses DC supply di rect current of suitable voltage derived from any convenient source, and leads 3 and 4 of the direct I ‘V current circuit D connect terminals I and 2 to these busses. Lead 3 contains an inductance ill intermediate terminal I and its direct current bus, and a signal recorder X is inserted in lead ll between terminal 2 and the other direct current bus. Although the signal recorders are herein indicated as being of the tape imprinting type, it is understood that any signal manifesting device may be used instead as, for example, acoustic means or relays controlling separate signal mani '10 festing or repeater circuits. A battery B, in the nature of a so-called ?oating reserve power sup ply, may be connected across leads 3 and 4. Busses AC supply alternating current, prefer- ' ably from the public utility line, to the primary I I of a transformer T. One terminal Ill of the transformer secondary I2 is grounded, whereas the other terminal I5 leads to conductor 7, which is part of an alternating current circuit A includ ing lead Sconnected to terminal I, a capacitance 2I, an inductance 23, recorders Z and Y, an in ductance 24, a capacitance 22 and lead 6 connect ing to terminal 2. Inductances 23 and 24, in series with condensers 2| and 22, are provided for the purpose of compensating the phase displacing e?ect of the capacitances, in order to decrease as far as‘ possible the impedance of the alternat ing current circuit. - The direct current derived from busses DC con tinuously supplies the signal loop L, so long as "30 the latter is not interrupted by the code signal sending means of an alarm box, or by a break 'in the line. Condensers 2| and 23 prevent direct current from entering circuit A, whereas circuit D is protected from alternating current by choke coil In which is so dimensioned that its inductance i 35 presents an alternating current resistance of a magnitude excluding for practical purposes the alternating current of A. It will be obvious to any one skilled in the art, that inductance it passes substantially only direct current and that capacitances 2| and 22 pass substantially only alternating current, so that the loop L may carry superposed direct current and alternating cur rent, whereas alternating current is excluded fromcircuit D and direct current from circuit A. The signal transmitters R, R’ and R” accord ing to my invention have a normally closed shunt ing switch 10 which opens when the box. is pulled and. remains open so long as the box movement is operative, namely, so long as the double code wheel 90 rotates. Arrangements of this type are well known in the art and for example shown .at d4 of Fig. 1 of Patent No. 553,838 to F. W. Cole. 555 2,128,578 2 The double code wheel 99 comprises two identical of the box. This grounding switch has princi pally the function of an auxiliary gap preventing toothed portions on a common shaft I99 and is adapted to actuate two sets of switch levers 99 and 91, 98 and 99, respectively. Switch springs 99 and 91, and 98 and 99, respectively, are mount ed on blocks of insulating material which elec trically separate the switch levers but permit their joint operation by the code wheel, which break down for example in case of an accidental connection of the signaling circuit with a power line. The above described arrangement with two code wheels on a common shaft, although capa ble of satisfactory operation, may under circum stances introduce the difficulty of necessitating upon rotating lifts and drops levers 91 and 99. In parallel with the shunting switch are spring exact alignment of the cams which, if not oper 10 contacts 96 and 91, connected to the signaling ating their respective switches with the proper time relation may cause unsatisfactory operation. lines leading to terminals I and 2, respectively. Spring contacts 9I and 92 are connected to the terminals of a non-interference magnet I99, op erative substantially only with direct current, and 15 also to another pair of spring contacts 93 and 94, Hence, an arrangement providing the same func 10 tion, but having only one code wheel, is preferable for practical purposes. An arrangement of this 15 type is shown in Figs. 2, 3, 4, and 5. respectively, which cooperate with contacts 98 and 99, respectively. Switch levers 98 and 99, herein referred to as grounding contacts, are joined to ground through conductor 95. Under normal, inoperative conditions, the followers of levers 91 and 99 rest on cams 69 of the code wheel, which keep them in elevated position, thereby connecting levers 99 and 91 with con As will be seen from Figs. 2 and 3, the arrange ment of switches, magnet and line connections is exactly as in Fig. 1. Instead of having separate code wheels, contact groups 9i, 92, 99, 91 and 93, 20 94, 98, 99 have separate followers M9 and 2H, respectively, pivoted at H2 and moving the con tact springs by means of insulator tips 259, 2I9. One of the followers, for example 2I9, is directly operated by a code wheel 299, as shown in Fig. 4. 25 tacts 9I and 92, respectively, whereas levers 98 From follower 2 I9 extends a rod 69 across to fol lower 2II engaging it in a recess thereof, so that the two followers and the two contact groups necessarily move concomitantly. As above de at 259 of Fig. 2, and permits free movement of levers 96 and 9?, if the non-interference magnet scribed with reference to Fig. 1, contacts 93, 99 30 and 94, 99 respectively close, and establish con nection to ground shortly after contacts 9|, 99 and 92, 9'5 respectively are opened. Pin 59 co operates in this instance with follower 2“ which is prevented from dropping if 99 is moved in front 35 of surface 25I of follower 2H. Contacts SI, 99, 92, 91 are then prevented from opening, exactly 25 and 99 are lifted from contacts 93 and 99. Pin 99 is associated with the armature of the non interference magnet I99, for example as shown 30 was energized during the initial signaling period of the box, notwithstanding a subsequent deen ergization due to the opening of the signaling circuit at 9I and 92 or a subsequently pulled box. A locking arrangement accomplishing this result 35 is, for example, described in Patent No. 1,244,587 to F. W. Cole for “Successive non-interference box”, dated October 30, 1917. If no current is ?owing in the circuit- due to previous pulling of as above explained with reference to Fig. l, ' whereas the operation of contacts 99, 99, 98, 99 is not affected. ‘It will now be evident without 40 vanother box or to some accident, and non-inter 40 ference magnet I99 is therefore de-energized upon the opening of ‘I9, the pin moves under neath lever 91 and prevents its dropping and therefore the opening of the circuit at 9! and 92. Therefore, if box R is pulled with the circuit 45 in good condition, as shown in Fig. l, the circuit remains closed over 99, 9I, I99, 92, and Si; ‘I9 is opened, magnet I99 remains energized, pin 59 is out of the way, and the circuit is opened and closed at 9I and 92 when the follower of 9'5 drops 50 in the interdental spaces of its code wheel, there by initiating code signals. Shortly after con tacts 9I, 96 and 92, 91, respectively, open, con tacts 93, 98 and 94, 99, respectively, close, and establish a ground connection. The ground con 55 nection at 98 and 99 is again interrupted shortly before contact is reestablished at 9! and 92. When box R is sending, and the line is inter rupted, as, for example, due to a break in the line as indicated at c, or due to another box 60 already operating, pin 59 prevents levers 96 and 9'I from dropping and interrupting the circuit at M and 92, whereas levers 99 and 99 are inde pendent of the non-interference magnet and establish ground connections at 99 and 99 every 65 time the follower of 99 passes over the teeth of code wheel 99. The above-described subject mat ter will be found in my above mentioned Patent No. 2,956,799. i Although this is not absolutely necessary, a 70 switch with contacts I98, I99 may be provided between ground and conductor 95. This ground ing switch is preferably operated together with the above described shunting switch l9, so that 76 the alarm box is only grounded during operation further explanation, that this arrangement op erates as described in connection with Fig. 1. Under normal conditions of the signaling cir cuit the new system operates as follows: If the line is wholly normal and none of the boxes is 45 operated or “pulled”, no alternating current ?ows in any part of the circuit since only one terminal of secondary I2 is connected thereto. Direct current flows in circuits‘ D and L and is excluded from circuit A by condensers 2i and 22 as herein 50 before described. Record-er X is normally ener gized, whereas recorders Y and Z are deenergized and, upon operation of a box, signals are received at X, recorders Y and Z remaining inoperative. The non-interference arrangement of the box 55 operates exactly as in a non-grounded system. However, boxes of the type according to the pres ent invention keep the signaling circuit closed, but establish ground, and signal over ground each time when the non-interference magnets are de 60 energized upon a box being pulled, so that the signals of two simultaneously sending boxes are received correctly. For example, if box R” is pulled ?rst and box R somewhat later, the direct current signals of R" are received at X, whereas 65 two alternating current circuits are established by box R. through ground and two branches of the signal loop, and corresponding signals are re ceived at Y and Z. Box R signals over Y and Z while box R’ ' operates, whereas upon R’ ' stopping 70 and releasing the direct current circuit, box R assumes control of the direct current circuit and its remaining signal impulses are also received at X. In the case of a broken circuit, as indicated at c 52,128,578 of Fig. 1, the direct current is interrupted, re corder X drops its: armature and becomes in capacitated, andsubstantially'no current ?ows in the system. "16 , Assuming now an accidentally grounded signal loop‘ as indicated at jg in Fig. 1, the direct current recorder or relay X remains energized, since the direct current circuit is not interrupted, but alter nating current cicuits including ground 9 and the respective adjacent branches of the signal loop are now established in addition, so that record ers Y and Z are also energized and. their arma tures attracted, indicating the faulty condition of ~15 the circuit. Since the direct current circuit is normal, correct signals are received at X from all boxes just as if ground g-were not present. If a short circuit'exists across a signal box, for example, around box R" as indicated at min Fig. 1, this box is not able to signal over the direct so current circuit since it is by-passed with respect thereto, but its signals are correctly received at recorders Y and Z, since upon becoming deener~ gized, the boxes drop the armatures of their direct current responsive non-interference mag nets and signal through ground as above de—‘ scribed. ' If both boxes-R and R", for example, are simultaneously pulled, both transmit understand able signals, box R over recorder X and box R” over the alternating current recorders. A short circuit across the entire signaling loop, as indicated at n of Fig. 1, in?uences the cir cuit as follows: Any one of the short circuited boxes is able to send signals over ground, which 35 signals are received at X and/or Y. However, under this condition, two or more simultaneously pulled boxes produce mixed signals since the non ‘3 lines in Fig. 5, and keeps switches 3M and .392 ‘open. If the- magnet I00 becomes deenergized anditsarmature drops, pin 350 moves to the posi tion shown in dotted lines in Fig. 6, and spring contacts 324-391 and 3\l3-—396 close. ' It will ‘now be evident that this arrangement ‘functions like the one previously described. Namely, during normal operation, contact pairs 93—98 and 99-99 close, and contact pairs 92_9'i and 9l-—99 open every time when follower 399 "170 ‘drops into an interdental space of code wheel 999. ‘If, however, the dropping armature of the non interierence magnet has retracted pin 359 from ‘contacts 396 and 391, switches 39! and 392 close, shunting-contacts 9‘l--91 and 94-98, respective ly, thereby preventing the opening of the normal signaling circuit at these points. Otherwise the function of this embodiment of my invention is exactly as described with reference to Figs. 1 to 5. It should be understood that the present dis 5:20 closure is for the purpose of illustration only and that this invention includes all modi?cations and equivalents which 'fall within the scope‘ of the appended claims; I claim: ' 1-. A signal transmitter comprising two ter minals, an auxiliary signaling connection, nor mally closed and normally open switching means connected in succession intermediate said aux iliary connection and each terminal respectively, ‘signal initiating means for rhythmically opening and: closing said ?rst switching means and clos ing and opening respectively said second switch ing means, said second switching means being closed subsequently to the opening of said ?rst as switching means and opened prior to the closing of said ?rst switching means, switch control interference mechanisms of all short circuited boxes are incapacitated upon being deprived of means, and means responsive to the amount of current ?owing therethrough for actuating said 40 their energizing direct current. vcontrol means, said actuating means being con v40 In circuits utilizing a transformer secondary i2 in series with the signaling loop, and having a nectedv to said‘ terminals in series with said nor grounded intermediate terminal (as shown in Fig. mally closed? switching means, and said control means maintaining said normally closed swtich 2 of application Serial No. 620,683), my new ing means in effectively closed position so long 45 alarm box functions in similar manner. as the current in said actuating means remains 45 Instead of mechanically locking (as with stop within a predetermined range. 59) the normal signaling contacts 9!, 92, 96, 91 2. A signal transmitter comprising two ter in closed position upon deenergization of the non minals, an auxiliary signaling connection, nor interference magnet, a similar effect can be ob mally closed and normally open switching means 50 tained electrically in a manner now to be de connected in succession intermediate said con 50 scribed by way of example with reference to Fig. 6. In this ?gure, there are again four contact nection and each terminal respectively, signal pairs 9l-96, 92—-9‘l, 93-98 and 94-439. How 55 ever, contact pairs 9|, 92 and 93, 94, which are in different switch units in Figs. 1 to 5, are now elec trically connected and mounted on contact springs 224 and 2l3, respectively. A single code wheel 390 with follower 3 l0 operates both contact units by means‘ of insulating actuator M5 and 60 likewise insulating connecter 3|6. It will be noted that contacts 94——99 and 93——98 are nor mally open and contacts 92-9'l and 9l—96 nor mally closed, establishing exactly the same circuit connections as the embodiments shown in Figs. 65 1 to 5. In addition, two shunting switches 3M and 392 are provided, having contacts 324, 391, M3 and 396 connected to contacts 224, 97, ‘M3 and 95, respectively. Contact pairs 324—391 and 3l3_39? are normally retained open by means of pin 359 which is actuated by the non-interference magnet I99. The actuating mechanism of pin 359 may correspond exactly to that of pin 59 of Figs. 1 to 5 and is therefore not again shown in Fig. 6. If the armature is attracted as shown in 75 Fig. 2, pin 350 is in the position shown in full initiating means for rhythmically opening and closing said ?rst switching means and in the same rhythm closing and opening respectively said second switching means, said second switch ing means being closed subsequently to the open 55 ing of said ?rst switching means and opened prior to the closing of said ?rst switching means, switch control means, and means responsive to the amount of current flowing therethrough for 60 actuating said control means, said actuating means being connected to said terminals in series with said normally closed switching means, and said control means maintaining said nor mally closed switching means in effectively closed 65 position so long as the current ?ow in said actuating means is substantially zero. _3. A signal transmitter comprising two ter minals, an auxiliary signaling connection, nor mally closed and normally open switching means, 70 conductors for connecting a normally closed and a normally open switching means in series in termediate said connection and each terminal re spectively, signal initiating means for rhythmi cally opening and closing said ?rst switching 75 2,128,578 4 nals, an auxiliary signaling connection, normal means and in the same rhythm closing and open ing said second switching means, a non-inter ly closed switching means and normally ener ference magnet connected across the conductors intermediate the ?rst and second switching means associated with each terminal respective ly, and means controlled by said magnet and across said terminals, a normally open switch ing means between a point of said series con upon deenergization of the magnet retaining said ?rst switching means in closed position said initiating means and said normally closed during operation of said second switching means. Li. A signal transmitter comprising two ter 10 minals, an auxiliary signaling connection, nor mally closed switching means and non-interfer ence means in series across said terminals, a nor mally open switching means between said nor mally closed switching means and said connec 15 tion, and signal initiating means for rhythmi cally opening and closing said ?rst switching means and in the same rhythm closing and open ing said second switching means, said non-inter ference means retaining said normally closed 20 switching means in closed position when deen ergized. 5. A signal transmitter comprising two ter minals, an auxiliary signaling connection, nor mally closed and normally open switching means 25 connected in succession intermediate said con nection and each terminal respectively, signal initiating means for rhythmically opening and closing said ?rst switching means and in the same rhythm closing and opening respectively 80 said second switching means, said second switch ing means being closed subsequently to the open ing of said ?rst switching means and opened prior to the closing of said ?rst switching means, normally open shunting contacts in parallel with said ?rst switching means, current responsive actuating means connected between said termi nals in series with said normally closed switch ing means and means controlled by said actuat ing means for closing said shunting contacts as 40 long as the current in said actuating means re mains within a predetermined range. 6. A signal transmitter comprising two termi gized non-interference means connected in series nection and said auxiliary connection, signal initiating means, actuating means intermediate switching means for rhythmically opening and closing said normally closed switching means in 10 response to said signal initiating means, a sec ond actuating means intermediate said ?rst actuating means and said normally open switch ing means for closing and opening said second switching means in the same rhythm, said non 15 interference means when deenergized arresting said second actuating means for retaining said normally closed switching means in closed posi tion. 7. A signal transmitter comprising two ter 20 minals, an auxiliary signaling connection, nor mally closed switching means having contacts connected between said terminals, normally open switching means connected between said aux iliary connection and said terminals, signal 25 initiating means for rhythmically opening and closing said ?rst switching means and closing and opening respectively said second switching means, said second switching means being closed subsequently to the’ opening of said ?rst switch 30 ing means, and opened prior to the closing of said ?rst switching means, means for controlling the effectiveness of said ?rst switching means, and means responsive to the amount of current ?owing therethrough for actuating said control 35 means and connected to said terminals in series with said normally closed switching means, said control means maintaining a current path across said contacts so long as the current in said actu ating means remains within a predetermined 40 range. FRANK R. BRIDGES.