US1490313A - Siren-control system - Google Patents

Description

"April15,.1924., 1,490,313 o. s. BURKE4 SIREN CONTROL SYSTEM April 15, 1924. .y 1,490,313

O. S. BURKE SIREN CONTROL SYSTEM Filed April 10. 1922 3 Sheets-Sheet 2 catio`n.

l tus and is 1.5 of soundreducing apparatus havin u pulls the nearest box.

Patented Api'. l5, 1924.

UNiTaD STATES PATENT ortica.

OSBERT S. BURKE, 0l' CHIUAG, ILLINOIS, ASSIGIDIOEv T0 FEDERAL ELECT-BIC COI- Pm, 0F GHICLGO, ILLINOIS,

L CORPORATION' 0l' ILLDIOIB.

slaan-connor. srs'rmr.

Appunti ma anni io, ma. semi no. tamos.

Il mois, have invented a certain new and useful Improvement in Siren-Control Systems, of which the following is a specifi-y My invention relates to signalling appararimarily adapted for manually controlled hre alarm systems. The object of the invention is to make it practicableI to employ a siren as the sound-producing mechanism. A siren is a' well-known piece a rotor capa le of rotatin at high spee tu produce vibrations in t e atmosphere for the production of sound. Itis usual to drive the rotor bly means of an electric, motor. In

giving auf ible fire alarm signals the coinmon practice is to employ code numbers having not more than two digits of a value of not over 5 each, which of course permits the.

- v sendingof 55 different signals. vWhere the v signals are given by bells, as has beencommon practice heretofore, the bell is struck a number of times corres onding to the first digit ofthe signal numlber, then there is a pause and then the bell is struck a number :o of times correspondin to the second digit of the signal number. Vhen the signal number is thus completed it is usually repeated after about 10 seconds or some interval longer than theone which occurs between u the two digits of the signal number. The

object of the repetition, of course, is to give the listeners an opportunity -to kcheck the 'signal and see that they have correctly interpreted it. Each repetition is referred to as a round and as stated, it is customary to give at least two rounds. In these manually olperated systems call boxes are distributed roughout the territory to be protected and when a signal is to be sent in the operator All he has to do is to pull ay hook or rotate a handle and then release it, after which the signal is given automatically. Such boxes, commonly known as fire alarm boxes, are well-known articles of commerce and need not be described'. -It has been foundpb practical experience that there is a natura time limit during whichthe full number of rounds shoul be completed. IThe boxes themselves lcation of the invention to are limited from a practical stand oint in the time that they can maintain action after a. single settin These limitations are practical rather t an theoretical,but nevertheless need to be taken into consideration. Another and more important consideration arises from the fact that in the case of fire or other emer ncy, time is of utmost importance and t e quicker the signal canbe run off the better. Experience in this count? teaches that the rounds should be run o in a period not to exceed 21) minutes or thereabouts. In using a bell or a whistle caable of giving short, sharp blasts, no di culty is -ordinarily experienced in completin the rounds within this period. A. siren as certain advantages over a bell or whistle, especially in that it isa rugged and reliable piece of apparatus and capable of emitting a large vo ume of sound, vbut vso far as I am aware a siren 'has notheretofore been employed for such purpose-,:n'e f reason bein that owing to the weightijantl inertia of t e moving parts the rotor-cou'ldnot be 'started and stopped withsuicientapromptness to make a siren available Yforthe urpose. My object is to overcomefthis illiculty and render it practicableito"employ a siren for signalling under-the conditions described. l A 1 I accomplish this object by the mechanism illustrated in the accompanying `fdrawings, in whichf f c Figure 1 is a diagram showing the applia 3-phase power circuit. 1

Fi res 2 and 3 are similar to Figure 1 but ow the parts in changed position. U

Figure 4 is a diagrammatic view showing the principle of operation of the reversing switch in the 3-phase system shown in Figures1,2and3.

Figure 5 is a diagrammatic view showing the invention as applied to "a direct current system. v y

Figure 6 is a diagram similar vto Figure 5 but showing the parts injchanged position.

Like numerals denote like out the several views.

Referring first to the' 3-phase alternating current type of apparatus shown in Figures 1mg. 4, l 1 represents the siren havingthree motor parts throughiot terminals a, y. As electric-driven sirens are Well-known, they need not be here described except to say that in my apparatus the siren motor is subjected to somewhat terl electrical stresses than usual and glelace it is desirable that the motor .be built with special ruggedness, the conductive elements being preferably built of solid copper. The mamsupply conductors A, B, C supply the electric energy for dr1v1n the siren motor. This motor is controlled y a reversing switch ywhich in actual practlce 1s referably in the form of a drum controller, but which for explanatory purposes I have illustrated as comprising a rotatable shaft having three sections' 5, 6, 7 insulated from each other. On section 5 are three conductive discs 10, 11, 12. On section 6 are three conductive discs 15, 16, 17. On section 7 are two conductive discs 19, 20, which form the movable elements of a maintaining switch.

Each disc in the order named has its respective contactor 21, 22, 23, 24, 25, 26, 27, 28. Discs 10, 15 and 19 are continuously conductive. Discs 11, 12, 16, 17 and 20 have insulating segments 31, 32, 33, 34 and 35 respectively. The angular extent of these discs will be hereinafter explained. Contacto'r 21 is connected by a conductor 40 to supply conductor C. Cont-actor 22 is connected by conductors 41 and 42 to motor terminal Contacter 23 isl connected by conductors 43 and 44 to motor terminal y. Contactor 24 is connected by conductor 45 to supply conductor B. Contacter 25 is connected by conductors 46 and 44 lto motor terminal y. Contactor 26 is connected by conductors 47 and 42 to motor terminal The supply conductor A is connected by conductor 48 to motor terminal a. Contacton 27 is connected by conductors 50 and 51 to the stationary contact 52 of a relay presently to be described. Contactor 28 is connected by conductors 53 and 54 to relay switch arm 55.

The shaft of the reversing and maintaining switches is driven b a Worm Wheel 6() engaged by a worm 61 astened to shaft 62 of a motor 63. For identification this will be referred to as the controller motor. In practice it is of a very small size, for

example, 1/20 H. P., its function being merely to drive the drum controller (reversfing switch), which has just been described.

Said controller motor is connected by a conductor 66 to one end of a battery 67 or other source of electric energy, the other terminal of the battery being connected by a conductor 68 to the conductor 51. It will thus be evident that when the relay switch arm 55 is closed the controller motor4 63 will be driven by the energy derived from the battery 67.

The relay switch arm 55 is controlled by an electromagnet, having an armature 70,

which actuates arm 55 and is in position to be magnetically controlled by the core 71 of a win ing 72. A tension spring 73 normally holds the armature in open position. The movement is limited by means of a stop 74. One end of the coil 72 is connected by a. conductor 76 to a battery 77. The remaining end of the coil and the remaining end4 of the battery are connected b conductors 78 and 79 respectively to what may be termed the district circuit, by which I mean the circuit running to the districts where the manual devices or boxes are distributed. I have illustrated the external circuit in accordance with common and well-known practice, in which the circuit is normally closed and the signa-lling device (which in my case is the siren) operates only when the circuit is open. I have also selected, to illustrate the manually operated devices, a typical fire alarm box, the principles and construction of which are wellknown. According to this system a plurality of boxes P, Q, R are arranged in series, and it will be understood, of course, that an number of such boxes, within reasonab e limits, may be employed. I have illustrated these boxes more or less diagrammatically. In the form illustrated each box has an arm 80, which presses toward a rotatable disc 81. This arm also constitutes one element of a switch, electrically connected to thel conductor 78 and adapted to electrically en-I gage a stationary contact 83l located within the box. Contact 83; is electrically connected by a conductor 84 to an arm 80 in the adjacent box, and this arrangement is repeated, thus placing all of the .boxes in series and normally maintaining a closed circuit.

Each disc 81 previously mentioned has teeth 86 adapted to lift its arm 80 so as to break contact with the stationary switch element 83. The disc rotates slowly with the result that the arm is alternately raised and lowered, and the contact correspondingly broken and established, thus de-energizin and energizing the coil 72 of the relay an energizing and de-energizing the controller motor 63. As the internal construction of call or signal boxes is so well-known, detailed description of the means for rotating the disc is not necessary further than to say that each disc has a pinion 90 fastened to it, which meshes with a gear wheel 91, the latter being driven b a spring 92, one end of which is fastene to the gear and the other to a lever or handle 93. The number of gears in this train may, of course, be varied. The parts are prevented from ro.- tating too rapidly by an escapement consisting of a pinion 95, which meshes with gear 91 and is fastened to an escapement Wheel 96, which co-operates with an oscillating pawl 97 faste-ned to a swinging penleases it, the disc 81 will be caused to rotate slowly in the proper direction to raise l. and lower the arm 80. Accordinsn` to common practice the parts are so timed that the disc will make two complete rotations or rounds, thus causing the signal to be given once and then repeated.

0perat1'on.-In Figure 1 I have shown the normal or at rest position of the parts. The reversing,r switchholds the siren motor de-energized, insulating segments 31, 32, 33 and 34 being in engagement with their respective contactors 22, 23, and 26. The insulating segment 35 is in engagement with contactor 24 and switch arm 55 of the rela is open. Thus the controller motor 63 1s on open, circuit and the controller stands still. If, now, an alarm is to be sounded,

a person approaches one of the call boxes P, Q, R, ulls the lever 93 and then releases it. his starts the disc 81 within the box to rotating slowl As soonas one of the teeth 86 comes un er the arm 80 and raises it, the latter breaks contact with the stationary switch element 83, thus deenergizing the coil 72 and permitting the spring 73- to close the switch arm 55 of the relay. As soon as'this arm closes, current is su plied to the controller motor 63 by the attery 67. This starts the motor, which rotates worm 61, wheel 60 and shaft 5, 6, 7. The rotation of this shaft causes the reversing switch to operate. The shaft makes a complete revolution for each of the teeth 86 of the particular box which has been pulled Each single rotation of the reversing switch causes a starting, driving and stopping of the siren motor. In otherV words. each tooth on thedisc of the pulled box will cause an individual blast from the siren. The angular extent and location of the insulatin segments of the reversing switch is suc as to first establish the ci'rcuit through the siren motor, then reverse the connections of thea, y terminals` and then disconnect the motor, thus causing a starting, running, retarding and de-ener iz'- ing of the motor for each com lete rot'atlon` of the discs. The reversing o the w, y terminals is illustrated with a conventional diagram i-n Figure 4, where it will be-seen that the reversing switch S will atlone time connect the main conductor B to the motor terminal m, and ythe main conductor C to the motor terminal y, and then reverse the motor connections and connect the sup ply conductor B to the motor terminal y, and the supply conductor C to the motor terminal Dilferently stated. the reversing switchy causes an interchange in the connections of the B, C supply conductors 44'and a complete re I have found that whereas it re uires about three seconds to obtain full spee from rest, the siren may be brought from full speed to rest in aboutsone second. It is desirable to give a longer interval between two rounds than between two blasts, for example, a period of about 10 Lseconds between rounds (that is before repeatin the signal) is appro riate, and I have, t erefore, found that wit my apparatus -a period of 2i minutes is ample time for giving a complete signal tition thereo To describe in etail the operation of the reversing switch and maintaining switchg.

The normal or at rest osition has already f Lbeen described and is il ustrated in Figure l. Let it be assumed that when the parts are in this position the district circuit. which controls the relay switch arm 55 is opened as a result of the pulling of theA box. The control motor 63 becomes energized from the battery 67 or other 'suitable source yof electric energy (it being possible, of course, to obtain such ener from the main sup ly conductors if desired). The controller shaft 5, 6, 7 rotates in the direction of the arrows, that is, clockwise according to the present drawings, and after a short interval the insulating segments 31 and 33 .wi-ll pass beyond their respective conductors 22, 25 whereupon the parts 'will assume the position shown in F1 ure 2 and the siren motor will be put on c osed circuit as follows:

The supply conductor A is connected to the motor terminal a through the conductor 48. The motor terminal is connected to the sup ly conductor C as follows: through the con uctors 42 and 41 to the contactor 22,

thence to the disc 11, shaft 5, disc 10, con-` maintaining switch goes into action whenA the insulating sector 35 has rotated'past the contactor 28 whereupon the circuit through the motor will be completed as follows:

from the disc v20 to contactor 28, thence through conductor 53 to one of the terminals of motor 63. The other terminal is connected through the conductor 66 through the battery 67 or other source of electrical energy, thence through the conductors 68 and 50 to the contactor 27, thence through the disc 19 and shaft 7 to the said disc 20. Thus the shaft is kept rotating until the segment 35 again comes into engagement with the contactor 28 whereupon the shaft will come to rest with the siren motor on open circuit as shown in Figure 1.

After the siren motor has rotated for a suiiicient period to give a single blast and the time comes when it should4 come to rest, this requirement is accomplished through the medium of the circuit changer or reversing switch, which causes a reversal of the connections of the a', y terminals and the B, lC supply conductors. Figure 3 illustrates the position of the reversing switch during this period of retardation and stoppage of the motor. To trace the circuits: the supply conductor A remains connected to the motor terminal a as before. The supply conductor B is connected to the motor terminal y as follows: throu h the conductor 45, contactor 24, disc 15, s aft 6, disc 17, contactor 26 and conductors 47 and 42. The supply conductor C is connected to the motor terminal as follows: throu h the conductor 40, contactor 21, disc 10, siaft 5, disc 12, contactor 23 and conductors 43 and 44. This reversal of the connections of the siren motor causes the latter to come to rest ve quickly, for example, in about a secon whereupon the parts reach the position shown 1n Figure 1 and the motor will remain at rest unless and until another tooth 86 opens the district circuit (through the relay coil 72).

It will thus be seen that the action is automatic after the box has been ulled and with my apparatus the siren will he controlled in suchmanner as to give comparatively short and distinctly individual blasts, which may be readily distinguished and counted by any-V one within hearing of the siren.

In the foregoing I have described the invention as applied to an alternating current power circuit. In Figures 5 and 6 I have illustrated the invention as a plied to a direct current power circuit. n this instance 'the siren motor is arrested by short circuiting the armature upon itself. This produces a dynamic brakin and brings the siren promptly to rest. eferring to Figures 5 and 6, the alarm boxes, relay and maintaining switch are the same as before.

The reversing switch and motor connections,

however, are different and will now be described.

Section 7 of the shaft is fastened to but insulated from a shaft section 100. Fastened to this section 100 are three discs101,

102, 103, which are of conductive material segment 111. The supply conductor D is i connected by a conductor 114 to contactor 106. f The component supply conductor E of opposite polarity is connected by a conductor 116 to the contactor 108. The contactor 107 is connected by a conductor 118 to one of the terminals of the motor 119 of the siren 120. The other motor terminal is connected by a conductor 122 (preferably through a small resistance 123) to the conductor 116. The field coil 126 of the siren motor is connected across the line conductors 127 and 128. represent the conventional connection and it will be understood that the method of energizing the field coils may be varied without departing from the spirit of the invention.

When the parts are at rest the insulating segments 110 and 111 will be in engagementl with their respective contactors 106 and 108. This normal or at rest position is not specifically illustrated in the drawings, as Figure 5 shows the parts'as they will appear after lthe siren motor has started. With the contactors 106 and 108 engaging insulating segments the siren motor will, of course, be disconnected from the power circuit. After the reversin switch has been rotated to the position s own in Figure 5, the siren motor will be energized as follows: from the supply conductor D through the lconductor 114, contactor 106, disc 101, shaft 100, disc 102, contactor 107, conductor 118 to one of the motor terminals, thence throu h the motor to the other terminal, thence t rough conductor 122, resistance 123 (if present) and conductor 116 to the opposite side E of the line. This condition continues until the time a preaches to cut oi the blast, whereupon t e insulating se ment 110 reaches the oontactor 106, t us disconnectin the motor from one side of the line. A er this condition has been maintained for a moment,

the insulating segment 111 comes to the end of its reach, passing out of engagement with the contactor 108 and permitting the latter to engage the disc 103. This causes short circuiting of the armature upon itself with consequentJ dynamic braking. The circuit through the armature may be traced thus: from one of the amature ter minals through the conductor 118, contactor 107, disc 102, shaft 100, disc 103, contactor 108, conductor 116, resistance 123 (if present) and conductor 122. This short-circuiting of the armature permits the -1 b3' the This is inten ed to llt) of a very large current, which causes a very rapid deceleration of the rotating parts in accordance with well-known principles.

. From the above it will be seen that in either type, alternating or direct current, by chan ing the motor connectionsthe rotor of te lsiren is brought quickly to rest and this makes it possible to produce a number of individual and readily distinguishable rblasts for sending .out the rerquired signal. As the operation is so largely electric in its nature, the apparatus may be readily kept in order and will require little attention, and at the same time will emit an audible signal having great volume of sound.

While I have illustrated the invention as embodied in a three-phase alternating current system and in a direct current system, it is also possible to apply it to a single phase system as shown in my copending a plication filed August 24 1922, Seria o. 5832982 but whether the siren motor is of the single-phase or poly-phase t pe it is, according to my invention, contro led by a phase changer, as recited in some of the appended claims.

Havin thus described my invention, what I c aim is new and desire to secure by Letters Patent is:

1. A signalling system of the type described having a siren provided with a rotatable sound producing. element, an electric motor for driving it, and means including a circuit changer for supplying electrical energy to said motor for causing it to rotate in one direction in one osition of the circuit chan er and for 'c anging electromagnetic con itions in the motor in another position of the circuit changer to produce a magneto motive force opposing such Jotationi f y h 2. si a ing system or giving s ort audible blsts, said system lhaving a siren provided with a rotary sound element and an electric motor for riving it, means including circuit conductors and switch elements 4for supplying electrical ener to said motor for causi it to rotate in one direction in one position of the switch elements and for changing electromagnetic conditions in the motor in another position of the switch elemen electromagnetic means for operating said switch elemente, and means for controllably energizingv said electromagnetic means.

3. .A signalling system ofthe type described having a siren -provided with a rotatable sound producing element, an electric motor for driving it, means includin a circuit changer for supplying.. electrica ener to said motor for causing it to rotate in one direction in one position of the circuit changer and for changing electromagnetic conditiom in the motor in 'antor, sai

roducing erefor for operatuX; said circuit changer.

paratus-for giving audible cod'e sig-` nals havin a siren provided with a rotary sound pro ucing elemen-t, an electric motor connected to it for rotating it, and means for supplying electrical energy to said momeans including circuit conductors and a rotary circuit changer which in one angular position establishes a circuit to produce a magneto-motive force tol rotate the rotary element of the motor in one direction. and in another an lar position establishes a circuit to pro. uce a magneto 4motive force in the motor to oppose such rotation,and driving means for rotating said circuit changer. l y

5. A si alingsystem for emitting short a code wheel 'imy audible b asts, having a siren provided with a a rotor for reducing the sound and an electric motor aving a rotating armature positively connected to said sound producing element` for accelerating and retarding it, a source of alternating current, and means for altering the phase relation between the field and armature windings to thereby at times rotate the armature and at other times. create electromagnetic opposition within the motor windings to the rotation of the armature, thus to bring it and the siren rotor promptly to rest.

6. A system for giving audible code signals having an electric motor, a siren having a rotary sound producin rotor rigidl connected to the rotor o `t e motor, an means includin for supplying e ectrical energy to said motorfor causing it to rotate in one direction in one an a chan r an for changing electromagnetic conditions in the motor in another angular position of the circuit changer to produce a magneto motive force opposing such rotation.

7. A system for giving audible code signals having an electric motor, a siren having a rotor connected to and driven by the rotor of said motor, means including a. rotary circuit changer for supplying electrical energy to said motor for causing it to rotate in one direction in one angular position of the circuit chan er and for changing electromagnetic con itions in the motor in another angular position of the motor, a power device for rotating the circuit changer and means for controlling said power device to cause it to impart full angular movement of said circuit changer.

8. A system for givingl audible code signals having a siren with a rotary sound producing element, an electric motor directly connected to itfor driving it,- a rotary cira rotary circuit changer' r position of the circuit' las cuit changer, a source of electrical ener and circuit conductors connected to Sad source and to the motor and controlled by said circuit changer whereby in one angu- 5 lar position of the circuit changer the motor will be supplied with electrical energy to cause it to rotate in one direction and in another angular position will change the electromagnetic conditions in the motor to oppose such rotation a power device for l0 rotating said circuit changer, and means including a code wheel box for controlling said power device.

In witness whereof, I have hereunto subscribed my name.

OSWBERT S. BURKE.

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