US1812616A - Automatic sound signaling and regulating system for microphones used in electric alarm systems - Google Patents

Description

June 30, 1931. J. P. WILLIAMS 1,812,616

AUTOMATIC SOUND SIGNALING AND REGULATING SYSTEM FOR MICROPHONES USED IN ELECTRIC ALARM SYSTEMS Filed Sept. 8, 1927 J44 Q n Patented June 30, 1931 I umran starts PATENT OFFICE;

JofrIN P. WILLIAMS, F BAYSIDE, NEW YORK, ASSIGNOR TO DUPLEX ELECTRIG COIM- PANY, OF NEW YORK, N. Y., A. CORPORATION OF DELAWARE AUTOMATIC SOUN'D SIGNALING AND REGULATIN' SYSTEM FOR MICROPHONES USED IN ELECTRIC ALARM SYSTEMS Application filed September 8, 1927. Serial No. 218,351.

This invention relates to an automatic .sound regulating and signaling system for microphones used in electric alarm systems.

Electric burglar-alarm systems as now usually employed for the protection of vaults or other structures comprise a. protective circuit concealed within the protected structure and so arranged that an attack thereon will cause actuation of the circuit and i send a'signal or alarm to a distant station or desired point. An example of such .protec-' tive systems is indicated. in my previous Patent No. 1, 56,926, of November 28th, 1922.

7 It has become the custom to also employ 1151! in such protective systems microphone units concealed within the protected structure and so arranged in the protective circuit that an attack involving noise or sound will actuate the microphone and cause operation of the 2 signal or alarm circuit. One example of the supplementary use of microphones in electric protective systems is indicated in my copending application for patent, Serial No. 207,538, filed July 21, 1927.

The microphone units usually so employed are of the type which operates on the same general principles as a telephone transmitter, in which any sound will disturb the diaphragm and the vibration of the diaphragm disarranges the normal position of small carbon balls resting against its back, and this disarrangement or stirring-up of the carbon balls modifies resistance of the microphone and correspondingly modifies the current passing therethrough. V

The difliculty experienced with such microphone protective systems has been that unnecessary signals or alarms have been caused by operation of the microphones under the 40. action of local vibrations or outside sound conditions (other than an actual attack by hammering, knocking or otherwise upon the protected structure), such as extraneous vi-' brations or sounds due to passing trolley cars, or trucks, near-by railroad trains, thunder storms, lightning, etc. Y Y

It is the object of mypresent invention to entirely and effectively overcome; the disadvantages existing in such microphone protective' systems, and to provide an improved regulating system of this type which will afford full protection agains false signals or alarms due to ordinary vibrations or sounds in the vicinity of the protected structure or to any inherent breaking or defect in the microphone unit itself.

To these ends'my improved system pro vides means intermediate of the microphone units and the main signal or alarm which is located at the distant station or desired point system for controlling the action of the microphone units to regulate or accumulate the vibrations preliminary to any actuation of the main signal or alarm.

Referring to the drawings, the dotted outline 14 indicates the vault or other protected structure, within which the microphones and regulating and controlling means and circuits thereof are protectively installed. The microphone units, indicated at 15 (I have herein shown two units in series), are in circuit with the protective system of the vault or protected structure, such protective circuit wires or conductors beingindicated at 16-17, and a battery or source of electrical energy, 18, and a meter relay of usual construction, 19, are included in the circuit. This circuit is completed through the microphones as follows: From the positive side of the battery18, through a wire, 20, to and through the coil, 21, of the relay 19, and from the coil through the wire 17 to the microphone 15 and across through a connecting wire, 22, to the other microphone 15, and fromthence back through the wire 16 to the negative side of the battery 18. This continuous normallyclosed circuit energizes the coil of the relay 19 and thus maintains the contact needle,'28, of the relay in the normal position as shown.

The sound regulating means is preferably mounted or enclosed within a suitable boxing or casing, as indicated by the dotted outline 24, and the mechanism is herein shown in a normally set position ready for operation.

The preferred mechanismcomprises a suitable clock spring movement adapted to be key-wound, the gears, indicated at 25, of which control the operation of a hand or pointer, 26, fixed upon a revoluble shaft, 27. Back of said pointer is mounted in fixed position a dial, 28, concentrically marked in steps to be indicated by the pointer.

I have herein shown the dial as marked in step points numbered 1 to 19 running clockwise from a central point 0 at the top (which central point is that at which the main signal or alarm will be actuated), but any other suitable step-marking may be employed. The pointer is manually set as de sired with relation to the step points and the number of microphone vibrations to be regulated oraccumulated to take up ordinary extraneous sounds before the main signal or alarm is actuated. For illustration, 1 have herein shown the pointer 26 set at the step figure 5, which will afilord five vibration steps (4:, 3, 2, 1) in operation before the pointer reaches the main alarm pointrO. The step movement of the pointer is the reverse of clock-wise, moving from the higher to the lower step markings on the dial, and is controlled in its operation under the suc cessive sound vibrations by the action of an electro-magnet relay, 29, having its armature, 30,, carrying a. dogging spring, 31, to the end of which is pivotally mounted a ratchet pawl, 32, engaging one of the clock movement gears 25. the action being such that the operation of the armature 30 causes the ratchetipawl 32 to lock and release the clock movement and thus effect the travel of the pointer 26 over the dial 28 in successive steps one point at a time.

Fixed to the pointer 26 and carried thereby, preferably back of the dial, is a disc, 33, of suitable insulating material, which disc carries two suitably spaced contact points, respectively indicated at 3 l85, both 01" which are grounded, as indicated at 36, to the positive polarity of the main operating battery, shown 2115737. In the travel of the pointer these contact points respectively and successively make contact with two spring contact plates, respectively indicated at 38 -39, which are in circuit to indicate the travel of the pointer 26 and respectively give a preliminary warning signal or alarm, and a final mainsignal or alarm.

The arrangement and location of the contact points 3435 and the contact plates 3839 may be as desired with relation tothe step points on the dial and the travel of the pointer. In the present illustration, the spacing of the contact points 34-35 is such that when the pointer 26 (set at the dial figure .5) moves to the dial figure 4; the spring contact plate 38 makes contact with the contact point 3-1 and completes a. circuit through a. Warning or preliminary signal which indicatesthat after four more step movements of the pointer, caused by vibrations or sound waves, it will be at the main alarm point 0 at which a signal or alarm will be sent to the distant alarm station, and when the pointer reaches the alarm point 0 the spring contact plate 39 makes contact with the contact point to complete the main alarm circuit.

It will be understood that the pointer 26 can be initially set at any desired point with relation to the dial scale, according to the number of vibration or sound steps it is desired to accumulate before the preliminary warning signal or alarm is given, and that,

in the successive step movements thus provided forbefore the main signal or alarm is actuated, when the pointer reaches the dial figure l (in the present illustration of the relative location of the circuit contact points and the contact plates 3839) the preliminary alarm or signal will be actuated.

T hen, if the step movements have been caused by extraneous or local vibrations 01' sounds other than an actual attack upon the protected structure, the pointer 26 can be again set back upon the dial scale to the'desired point for further regulation of such extraneous vibrations; but, otherwise, if the vibrations or sounds continue or are caused by attack, the further step movements of the pointer will continue until the main alarm point 0 is,

reached, at which the main signal or alarm (which may be a gong, siren, lamp, or any other audible or visual device) at the main station will be actuated.

In the step-movement travel of the pointer and its disc the circuit of the preliminary warning signal or alarm will be broken as soon as the contact point 34: passes the spring contact plate 38, and the circuit of the main signal or alarm will be set in operation as soon as the contact point 35 reaches the spring contact plate 39. V

' In operation, when the sound waves, caused by vibrations or an attack upon the protected structure, act upon the diaphragm of the microphones 15, disturbing the position of the carbonballs in circuit and thus changing the total resistance of the microphones, which resistance change is of course due to the volume of the sound wave acting upon the diaphragm, the sudden change in resistance sets up a pulsating current on the before described clos'ed circuit through the coil 21 of the meter relay 19, and this pulsating current causes the contact needle 23 of the relay operating battery 37 through a wire, 41, to-

and through the contact needle 23 and contact point 40 and a wire, 42, to the coil, 43, of an automatic-drop relay, indicated at 44, and fromthence through a wire,'45, back to the negative side of the battery 37.

The foregoing circuit energizes the coil of therelay 44 and attracts its armature,46, and the armature makes contact with a contact point, 47 when another circuit co1nplete'd through the coil, 48, of the electro- V magnet 29 which controls the action of the sound regulating or accumulating mecha nism, through conductors and meansias follows: From the positive side of the operating battery 37, which is grounded, asindicated at 49, to the ground, indicated at 50, of the electro-magnet coil- 48, through said coil 1 and a wire, 51, to the contact 47 and through the relay armature146 anda wire, 52, to the Wire 45, and from thence to the negative side of the battery 37. 1

From the foregoing description it will'be noted that three circuits arecomprised in the initial operation first, the initial normally closed protective circuit; second,=an inter mediate circuit which is actuated by the opening of the protective circuit; and third,.a supplementary circuit which is actuated by the intermediate circuit and which in turn controls the operation of the regulating mechanism which governs the signaling or alarm circuits.

When the actuation of the supplementary circuit above described energizes the coil 48 of the electro-magnet 29, the armature 30 thereof is attracted and this releases the pawl ratchet 32, through the lifting of the dogging spring plate 31 carried by the armature, and the operation of the clock-spring movement of the regulating mechanism starts.

It will be understood that the foregoing action of the circuits and consequent operation of the clock-spring movement is caused by a single vibration or sound wave action upon the. microphones, and that when this single vibration ceases the microphones will resume their normally-closed circuit status through the carbon balls, the circuits before described will resume normal status, and the clock-spring movement will be again locked upon release of the armature 30 of the electro-magnet 29. By this action every single vibration of a given volume or sound causes the pointer 26 to move one step at a time over the dial scale until the points are reached at which the preliminary warning signal or alarm and then the main signal or alarm will be respectively actuated.

The. respective signal or alarm circuits, respectively including the spring contact plates 38 39, are completed through conductors and means as follows: When the contact. plate 38 comes in contact with the initial contact point 34 on the disc 33carried by the pointer 26, the warning-signal circuit is completed from the ground 49 of the positive side of the operating battery 37 to the ground 36 .of contact point 34, and from thence through said contact point and the contact plate 38 and a wire, 53, to and'through the warning signal or alarm, indicated at 54, (which may be a bell or other adapted means) and through a wire 55, backto the negative side of the battery 37. The completion of this warning signal circuit indicates that the pointer 26 is approaching within'a few step points of themain alarm point 0 and that in order to avoid theactuation of the main signal orfalarm unnecessarily by extraneous vibrations from any cause other than actual attack upon the protected structure the pointer 26 should be moved back a desired number of steps on the scale of the dial, andas soon as this is done the just described warning circuit is of course broken.

But, under conditions of upon the protected structure, the consecutive blows or hammering each cause a step movement of the pointer 26, and as the blows con tinue the warning circuit is first actuated and as the pointer continues its movement the warning circuit is broken and the main signal or alarm circuit is completed, as soon as the alarm point 0 is reached and the contact point 35 is in contact with the contact plate 39, from the ground 49 of the positive side of the battery 37 to the ground 36' ofcontact point 35, and from thence through said contact" point and the contact plate 39 and a wire, 56,

to and through the main signal or alarm, indicated at 57, and through a wire, 58, and

the'wire 55 back to the negative side'of the battery 37 It will thus-be noted that there are two an actual attack operation the preliminary warning signal cirj cuit is broken and there is no possibility of any current passing through the wire 53 and V the warning signal 54. 1 1

It will also be noted that the before described intermediate circuit which 'is actuated by'the initial protective circuit and I which actuates the automatic-drop relay 44, and the supplementarycircuit which is -ac-,

tuated'b'ythe intermediate circuit and which actuates' the electro-magnet 29 which operates J to release and lock the regulating means, and also the two respective circuits from theregulating means and which respectively ac-r tuate the warning signal and the main signal, are. all operative on the mainoperating battery or source of electrical energy 37, and that the initial protective circuit operates on its own battery 18.

It is also to be understood that the device operates equally as well with a'plurality of continuous alarms of intermittent duration as Well as an alarm of continuous duration as the continuous sounds, and effect the microphones the same as a plurality of intermittent alarms. The device will thus operate either on the intermittent sound such as hammering, or on a sustained sound such as a Whistle or drilling.

The operation and advantages of my invention will be readily understood. By merely setting the pointer 26 at the desired point on the dial scale any desired number of microphone vibrations can be regulatedor accumulated before the warning signal or alarm is actuated, and when the warning signal is given. the pointer can be again reset if desired, as the numberof extraneous vibrations or sounds differs according to the locality of the protected structure, and thus any unnecessary or false alarms by actuation of the main signal or alarm will be conveniently and effectively avoided, but the main signal or alarm will be actuated, in the event of an attack upon the protected structure, as soon the regulated number of vibrations as provided for in the desired setting of the mechanism have beenaccumulated and the pointer reaches the alarm point 0 in its step movements. 1

I do not desire to be understood as limit.- ing myself to the detailconstruction and arrangement of parts as herein shown and described, as it is manifest that variations and modifications therein may be resorted to, in the adaptation of my invention to varying conditions of use, without departing from the spirit and scope of my invention and improvements. I therefore reserve the right to all such variations and modifications as properly fall within the scope of my invention and the terms of the following claims.

Having thus described my invention, I

claim and desire ent I to secure by Letters Pat- 1. A microphone protective system of the class described for a structure to be protected,

comp-rising a microphone sound detector located in a position to be actuated during a burglarious attack, a relay in circuit with said microphone, movable means controlled by said relay responsive to both intermittent and continuous vibrations of said sound detector, and an alarm circuit controlled by said means to actuate said alarm only after a predetermined movement of said means.

2. A microphone protective system of the class described for a structure to be protected comprising a microphone sound detector located in a position to be actuated during a burglarious attack, a relay in circuit with said microphone, a movable accumulator mechanism, an escapement mechanism controlled by said relay and moving said accumula'tor mechanism, said escapement mechanism being moved in response to both intermittent and continuous vibrations of said sound detector, and an alarm circuit controlled by said accumulator mechanism to actuate said alarm only after a predetermined movement of said accumulator mechanism, said accumulator mechanism being adapted to be reset a predetermined amount.

8. A microphone protective system of the class described for a. structure to be protected, comprising a microphone sound detector located in a position to be actuated duringa burglarious attack, a relay in circuit with said microphone and operated by the vibrations thereof, an escapement mechanism controlled by said relay responsive to both intermittent and continuous vibrations of said sound detector, an alarm circuit controlled by said escapement mechanism to actuate said alarm after a. predetermined movement of said mechanism, a dial and a manually controlled means to reset said escapement mechanism a predetermined amount on said dial to determine the extent of movement thereof before actuation of said alarm.

In testimony whereof I have signed the foregoing specification.

JOHN P. WILLIAMS.

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