US 1765598 A
Description (OCR text may contain errors)
Patented June 24, 1930 masse r y ori-aca .mums L. Neem1r AND GENNERO' DE encon, or Fonns'r HILLS, PENNSYLVANIA, AssIGNoRs 're WEs'rINeHoUsE ELECTRIC' AND MANUFACTURING COMPANY, A;
CORPORATION 0F PENSYLVANIA TELEPHONOMETER Application filed March 12, 1929.1 Serial No. 346,339,
Our invention relates to signalling systems and, in particular, to systems which are adapted to give an automatic response indicative of some condition at a point rcmote from the receiving end ,of the system.
With the increase in the number of automatic plants of various kinds that has occurred in recent years, a necessity has arisen for a signalling system which will indicate the condition of apparatus at a distant point to an operator at a central statlon. Numerous types of signalling systems have already been proposed but are subject to certain disadvantages.
We have decided that, since practical'ly every distant station or plant is connected With its control center by telephone circuits, the signalling necessary to be carried .on between the distant station and the central station may well be transmitted over existing telephone circuits.
It is an object ,of our invention, therefore, to provide automatic means for transmitting an indication of the condition of a piece of apparatus in a distant station, over telephone circuits, in response to a telephone call originated at a central station.
Our invention, in its broader aspect, has for another object the provision of a telephonic system of remote metering.
t is a particular lobject of our invention 'to make use of standard telephone instruments and existing circuits'for the transmission of meter readings or other similar information.
In accordance with our invention, we provide a simple system for automatically producing a codeof sounds in accordance with the reading of a meter or register at a distant oint, for transmission over telephone circults. Our invention includes means responsive to the Ioperation of the ringer or the telephone bell in the distant station for lifting the telephone receiver thereat and initiating the operation of the code-sending equipment.
A thorough understanding of our invention may best be obtained by a study .of the accompanying drawing in connection with the following description thereof.
The single ligure of the drawing is a diagrammatic illustration of the apparatus and circuits necessary inan embodiment of our invention. v
Referring, in detail, to the drawing, our invention comprises a control station 10 and a distant station 11. It is contemplated that automatic apparatus will be installed at the distant station and, in the particular example of `our invention described, it is assumed that the distant station is an automatic hydro-electric generating or pumping station. ln such installations, it is desirable for an operator at a central station to be able to check the water level available for generation of power or other purposes, although it is obvious that our system may be applied to the transmission of indications other than that mentioned. v
The central, station and the distant station are connected by telephone circuits 12, the apparatus included in which' is indicated schematically and comprises the usual transmitter, receiver, hook switch and ringer.
The distant-station telephone set includes the same apparatus, the ringer 13' being shown in more detail in order to explain the v operation of the signalling system. ln connection with the sub-station telephone transmitter 14, a speaker/515 is illustrated, the purpose Iand function'of which will appear hereinafter. A solenoid 16 is provided for lifting the receiver of the sub-station telephone from its hook toestablish communication between the two stations in response to a calltrom the central oce, as will be explained later.-
rlhe remainder of the apparatus shown in the drawing will be described in connection with the following explanation of its operation.
Let it be assumed that the operator at the central station desires to check the waterv level at the distant station. ln such case, he will place a call for the distant-station telephone through the standard telephone system,either by calling an operator or by dialing the correct number, depending upon whether the telephone system is of the manual or machine-switching type. When a circuit has heen established through the telephone exchange between the central station and the distant station, the ringer 13 at the distant station will be energized by alternating current in the well lrnown manner. Then the armature of the telephone ringer at the substation yibrates,` it will engage an associated contact momentarily to establish an obvious energizing circuit for a re' lay 17 a. 'l` he relay 17a, as indicated hy the shaded end ci the core thereof, is of the slow-release type. A slow-release relay is a relay that does not release its armature until a short: time after its coil is deenergized. This provision makes it impossible to start the system as a result of an accidental inomentary energization of the relay 17a.
W hen the ringer 13 operates, the relay 17 a actuates its contacts. rlhe operationoi the relay 17a interrupts, at the contact 17, a normally closed holding circuit for a relay 18 which `is energized so long as the codesending equipment is idle. rlhe relay 18 is also a slow-release relay and, after a short interval, releases its contacts. rlhis operation results in the completion of a locking circuit for the relay 17a, including vthe contact 19 of the relay 18 and the contact 2O or the relay 17a.
An obvious energizing circuit is simultaneously completed through the contact 17 of the relay 17a, for the relay 21. A similar circuit is completed for the relay 22, including contact 17 of the relay 17a, contact 23 of the relay 18, Contact 24 oi' a relay 25, contact 26 ofY a relay 27 and the winding of relay 22. At armature 17', the relay 17a interrupts a circuit to relay 22 :for a purpose to be explained later. Armature 18 oit relay 18 connects positive battery terminal to this circuit but only after it has heen opened at armature 17 rl`he relay 21, when energized, completes an obvious energizing circuit for the solenoid 16 which is adapted to lift the receiver of the sub-station telephone.
lhe relay 22, when energized, completes a locking circuit for itself through its contact 28 and the contact 29 of the relay 27, although its original energizing circuit is maintained until relay 25 operates. The operation of the relay 22 also completes a circuit for a stepping magnet 3G which is adapted to step the wipers 31, 32, 33 and 34 of a selector switch 35 from one of their associated contact points to the next. This circuit includes the contact 36 of the relay 22, ythe contact 37 of a relay 38, and the winding oi the stepping magnet 30.
Then the stepping magnet 30 is energized, the selector switch prepares to advance its wipers from their `lirst. to their second contacts and a circuit is simultaneously completed for a slow-release relay 39 at the Contact 40 of the magnet 30. After treaties gized, 'the wipers 31, 32, 33 and 34 of the selector switch 35 are advanced 'onefstep, and the energizing circuit for the relay 39 is interrupted at the contact 40 of the stepping magnet. The stepping magnet is a ain energized, as previously explained, an at the contact 40, completes the circuit for the relay 39 a second time. The VVrelay 39 is again energized to complete a circuit for relay 38 which interrupts the circuit of the stepping magnet at armature 37, and this alternate energization of the relays continues, thus slowly stepping the 4wipers of the switch from point to point.
When the wipers engage their third contacts, a circuit including the wiper 32, the contact 44 of a relay 45 and its hack contact, a buzzer 46, the primary winding of the transformer 42, and a condenser 46', is momentarily completed. A sound impulse is thereby produced at the sub-station telephone transmitter hy the speaker 15 which is connected to the secondary winding of the transformer 42 and the contact 43 of relay 38. In accordance with the foregoing' the time' delay in the release of said armature is adjusted to permit the circuit; for the speaker 15 to be completed before the selector switch advances another step. Successive impulses will thus be produced hy the continued operation of the selector switch to indicate the positionY of a iioat switch 47 which is shifted in accordance with the level or" water in the orebay or storage basin 48. rlhe production ot sound impulses will be stopped when the indication has been transmitted, in the following manner.
Assume that the doat switch 47 is in engagement with the contact 49 thereof, when the wiper 31 oi' the selector switch 35 engages its corresponding contact 50, a circuit will be established for the relay 45. rllhe operation of the relay 45 completes a locking circuit therefor at its contact 51, interrupts the circuit to the huzzer 46 at its armature 44 and, at its' armature 52, closes a spinning circuit for the stepping magnet 30, including the winding thereof, the contact 52 and the contact 40 oi the stepping magnet. rllhe production oi sound impulses by the buzzer 46 is thus stopped and the selector switch is rapidly advanced from point t0 point Without the time delay introduced by the relays 38 and 39 between steps, since the stepping magnet interrupts its own circuit.
lt is believed to be apparent, from the foregoing, that the number of sound impulses produced depends on the position oit the float switch and, therefore, indicates the height of the water level at 48. lt is olivious, of course, that the position of any other indicator, meter, or register, may be transmitted by the same means.
When the Wiper 32 reaches its thirteenth or last contact (although contactbanks having more than thirteen contacts may be used), an obvious energizing circuit is completed for the relay 25. The relay 25 thei'eupon closes its contacts to complete its own locking circuit through its contact 52 and the back contact .29 of the relay 27, and to set up a circuit from the eleventh contact associated with the Wiper 32 through thev front contact 53 of the relay 25 to the winding of the relay 27. This circuit is not completed, however, until Wiper 32 engages its eleventh contact in its second revolution. At contact 24, of relay 25 the original energizing circuit for the relay 22 is interrupted but this relay remains locked in through its contact 28 and contact 29 of the relay 27.
As the wiper 31 engages its twelfth and thirteenth contacts, the energizing circuit for the relay 45 is shunted and the contacts of said relay are released to restore the buzzercircuit to normal and re-establish the original energizing circuit for the stepping magnet 30. The selector switch 35 is again stepped from point to point to repeat the indication of the position of the float switch been completed, its wipers will/berapidly.
stepped past the contacts in' the latter portion of its path ot travel. VJ hen the wiper 32, in its second revolution, engages its eleventh contact, the circuit that was prepared by the energization of the rela-y 25 at its contact 53 for the relay 27 is completed. The operation of relay 27 closes lookin circuit for itself at its .contact 54 throug the wiper 33 which movesn from Contact to contact with sufficient rapidity to prevent deenergization of the relay. At armature 29, the locking circuits offrelays 22 and 25 are interrupted and these relays deenergized. The relay 27 causes positive battery current to be supplied through contact 29, Wiper 34 and its eleventh contact, to the Winding of relay 18.
The deencrgization of relay 22 interrupts the original energizing circuit for the stepping magnet 30 at contact 36, but a parallel circuit from positive battery terminal through the wiper 33 and armature 37 of relay 38 continues the stepping operation until the selector switch returns to normal, when further stepping is precluded vsince the first contact of Wiper 33 is not connected to battery.
rlhe energization of therelay 18 deenergizes relay 17a by opening its locking circuit at contact 19, and the subsequent deenergization of relay 17 a restores the locking circuit for the relay 18 at its contact 17. The relay 21, solenoid 16, and all the remaining relays, with the exception of the relay 18, are deenergized and the system is returned to its normal, idle condition.
The circuit controlled by the contacts 1 and 18 of the relays 17 and 18,'respectively, serves to prevent false operation ofthe system in case of battery failure.
Although the drawingA includes a plurality of conventional representations of the substation battery, this expedient was adopted merely to obviate complication of the drawing by extending all circuits to a common battery, such as will be generally employed in an actual embodiment of our invention. i
lt will be apparent from the vforegoing description that the system of our invention accomplishes the automatic transmission of an indication from a distant, unattended station, to a central otiice, as the result of a telephone call made, in the usual manner, through the'existing telephone system.
vNumerous applications for the system shown and described will, no doubt, occur to those skilled in the art, as Well as changes in the details of the disclosure. 1t is not our intention, therefore, to be limited to the exact embodiment of the invention as descibed and claimed, except `as indicated by the appended claims;v v
We claim as our invention: y 1. ln a signalling system, theY combination with a dispatchers othce and a remote station, telephones at said oilice-and station adapted yto be connected through a public telephone system, of a solenoid at said station for lifting the telephone receiver thereat, a relay controlled by the telephone ringer for energizing said solenoid, a measuring device at said station, and means including a selector switch responsive to the operation of said relay for producing a number of sounds at the transmitter of the substation telephone determined by the condition. of said measuring device', and means for .causing the sound-producing means to re- `lll) tion having a telephone therein oonnectiblel vto a public telephone system, means responsive to the signal calling for the telephone for lifting the receiver, and means further responsive to the calling signal Jfor producing, at the transmitter of the telephone, a sound code indicative of the position of the metering device, thereby to cause the transmission of a sound code over the telephone systemI to a distant calling party.
4. In a' signalling system, the combination with a iii-st station and a second sta-y tion, telephones in each station connected by 'a telephone system, of a solenoid for lifting the telephone receiver at the 'second station, an indicating device, meansV at the second station for producing sound codesl at the transmitter of the telephone in accordance with the position of the indicating device, and means responsive to the operation of the ringing device of the telephone at .the second station for simultaneously'instituting the operation of the receiver-lifting device and the sound-code-producing means to effect the transmission of a sound code over the telephone system to the first station.
5. In a signalling system,'the combination with a first station and a second station, telephones in each station connected by a telephone system, of a solenoid for lifting the telephone receiver at the second station, an indicating device, means at the second station for producing sound codes at the transmitter of the telephone in accordance with the position of the indicating device, means responsive to the operation of the ringing device of the telephone at the second station for simultaneously instituting the operation of the receiver-lifting device and the sound-code-producing means, and means for causing said sound-code-producing means to transmit two complete sound codes over the telephone system to the first station and subsequently deenergize the receiver-lifting solenoid.
G. In a' signalling system, the combination with a dispatchers office and a substation, telephones at said ofiice and substation adapted to be connected through a public telephone system, of means responsive to the ringing of the substation telephone for lifting its receiver, a measuring device,
means for producing sound codes at the sub'- station telephone transmitter, a selector switch` for controlling the operation of said sound-producing means, said selector switch being set in operation in response to the ringing of the substation telephone bell to cause the' sound-producing means to produce a sound code in accordance Withthe position of the metering device, and means for causing the selector switch to eiiect the production of the sound code a predetermined number of times and subsequently restore the system to normal.
7. ln a signalling system, the combination with a dispatchers office and a substation, telephones at said office and station adapted to be connected through a public telephone system, of a solenoid for lifting the receiver of the substation telephone, a measuring device, a loud-speaker positioned in front of the telephone transmitter, a buzzerv device for operating the loud-speaker, a distributor associated With the measuring device for controlling the operation of the buzzer device, means responsive to .the ringing of the substation` telephone bell for initiating the operation of the distributorl and effecting the energization of the receiver-lifting solenoid, said distributor being disposedito automatically eifect a pre determined number of buzzer operations in accordance with the position of the measuring devicegto transmit a sound code over the telephone system 4to the dispatchersl oiice, and means for stopping'the distributor after tWo complete sound codes have been transmitted.
In testimony whereof, We have hereunto subscribed our names this 9thA day4 of March, 1929.
' JAMES lL. MCCY.
GENNERO DE CROCE.