US2116255A - Signal code sending system - Google Patents

Signal code sending system Download PDF

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US2116255A
US2116255A US2116255DA US2116255A US 2116255 A US2116255 A US 2116255A US 2116255D A US2116255D A US 2116255DA US 2116255 A US2116255 A US 2116255A
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    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B27/00Alarm systems in which the alarm condition is signalled from a central station to a plurality of substations
    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B27/00Alarm systems in which the alarm condition is signalled from a central station to a plurality of substations
    • G08B27/001Signalling to an emergency team, e.g. firemen

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  • the present invention relates to an improved signal code sending system for controlling the operation of various kinds of electrical signal devices, calling and locating individuals by code number, as well as the sounding of time and fire alarms being well known uses of such a system.
  • an improved signal code sending system which can be installed with great facility
  • Fig.- 1 is a schematic view illustrating the physical appearance of the system as a whole.
  • Fig. 2 is a wiring diagram showing the electrical connections of the system shown in Fig. 1,
  • the system also comprises control mains 3, preferably in the form of two conductor twisted cord usually employed in the installation of low voltage apparatus, the control mains 3 providing a number of outlets 4, such as ordinary jacks or terminal blocks, disposed throughout the system adjacent to the power outlets. 2. Since all the control wiring may be installed with the same facility and low cost associated with the installation of low voltage apparatus, the low voltage control mains 3 can be extended to various parts of the building in which the system is employed to suit the 55 location of the power outlets 2 already installed,
  • a portable code determining and code sending apparatus 5 or" the type shown and de- 5 scribed in Patent No. 1,823,586, issued September 15, 1931 to Herbert Burdick, although obviously the system may be employed in connection with other types of similar apparatus.
  • the reference character A designates a code 10 determining, or setting, device cooperating with a code sending device B, in a manner hereinafter described.
  • the apparatus 5 provides. a cable 5 carrying at its end a suitable plug 1 for insertion in a power outlet 2, as well as a length of 15 twisted cord conductor 8 carrying at its end a plug 9 for insertion in the nearest outlet or jack 4.
  • the code determining device A and its. associated code sending device B are adapted to be energized and to operate at the voltage of the supply mains I, and the functioning of the code sending device 8 is adapted to intermit- 30 tently energize the conductors of the chord 8 at a voltage different from that of the mains I, as determined by a transformer T, forming part of the apparatus 5. Consequently, with the plug 9 in a jack 4, each energization of the cord 8 is 35 adapted to transmit a signal impulse to the control mains 3, throughout the system.
  • Each signal unit I0 provides a cable ll carrying at its end a suitable plug I2 for insertion in a power outlet, as well as a length of twisted cord conductor I3, carrying at its end a plug I4 for insertion in a jack 4.
  • a signal unit II] it is only necessary to mount the unit adjacent to the nearest pair of outlets 2 and 4, as by means of wall studs Ilia, see Fig.
  • a portable booster transformer unit T which provides a cable It carrying at its end a suitable plug it for insertion in a power outlet 2.
  • the booster transformer T also provides two lengths of twisted conductor cord H and i8 carrying at their ends plugs I9 and 20 for insertion in an outlet 4 of the mains 3, and an outlet la of auxiliary low voltage supply mains 3a, respectively.
  • the system can be extended indefinitely by installing one or more booster transformer units T, at any desired points.
  • each booster transformer unit T is entirely portable, and its installation is completely accomplished by inserting its three plugs i6, i9 and 28 in one power outlet 2, and in adjacent outlets Q and id of the mains 3 and 3a, respectively. Since as will hereinafter appear, the primary winding of the booster transformer T is adapted to be energized from the supply mains i, only in response to energization of the mains 3, energization of the auxiliary mains 3a from the secondary winding of transformer T is under the control of the code deterrruning and sending apparatus 5. And for the same reason, duo-potential signal units iii, respectively connected between adjacent pairs of power outlets 2 and low voltage jacks Ga, are adapted to operate in unison with the signal units it connected between power outlets 2 and jacks i.
  • the code determining device A consists of a series of parallel bus bars A-i to Aiii inclusive, with the terminals thereof connected to a corresponding number of terminals of codesending device B.
  • the code sending device B comprises a commutator providing a number of groups of contacts C-l to 0-9 inclusive, which are connected to the bus bars Al to Al9, the corresponding contacts of each group being interconnected, as partially indicated.
  • the commutator also provides a brush arm 2i rotatable with a shaft 22, the arm 2i carrying at one end a double brush 23, insulated therefrom, with an outer finger adapted to ride over the surrounding commutator contacts, while an inner finger rides around an annular contact ring 24.
  • the ring 2 2 is connected to one of a pair of spaced contacts 25 adapted to be bridged by a pivoted switch bar 26, operating in unison with the commutator shaft 22, as hereinafter described.
  • the brush arm 25 carries at its other end a second double brush 2?, insulated therefrom, which provides a pair of brush fingers, the outer one of which bears on an annular contact ring 28 that is permanently connected to the bus bar A- i through commutator contact Cl.
  • the ring 28 provides an insulated gap at 28c, which the finger 2i engages when the device is at rest.
  • the inner brush finger bears on a third contact ring 25 that is connected, in parallel with the bus bar A-l ii, to one terminal of the operating winding of the sending device B.
  • the other terminal of winding 39 is connected to one of the mains I through a pair of contacts 3
  • the winding 30, when energized, is adapted to attract a pivoted armature 32, the free end of which is connected to a crank
  • the crank 33 is connected by gearing 34 to a pawl 35 adapted to engage a ratchet wheel 36 turnable with the commutator shaft 22, each attraction of the armature 32 serving to turn the commutator brush arm 21 through the displacement of one armature contact.
  • a spring serves to retract the armature 32 and advance the pawl 35 for another step.
  • An arm 31 carrying the pawl 35 is adapted to operate the switch bar 26 through a toggle connection 38, the bar 26 being thrown from the dotted to the full line position of Fig. 2, upon each attraction of the armature 32 by the winding 36.
  • this movement of the bar 26 in step with the advance of the commutator brush arm 2! serves to break the circuit of the winding 36, whereupon the spring serves to retract the armature 32 for another step which takes place upon reclosing of the switch contacts 3 I.
  • the code determining device A provides a number of keys K movable transversely of the bus bars, fingers serving to determine various code combinations between the keys and bus bars.
  • the bus bar A-l is under voltage from one supply main i, and the code setting device is at rest, with one terminal of the operating inding 38 under voltage from the other main 1 through the closed switch contacts 3 4.
  • a circuit is at once established from the bus bar Al to the bus bar A-lll, through corresponding fingers to the open side of the winding 38, whereupon the armature 32 is attracted to turn the brush arm 2!
  • This first step of the sending device B establishes a circuit from one main 5 through bus bar Al, contact C-i and ring 24 to one of the spaced contacts 25 that are bridged by the switch bar 26 upon each step of the brush arm 2!, and this action automatically causes the energization of the control mains 3 and 3a of the system, in accordance with the code, at a voltage different from that of the mains i.
  • the other contact 25 of the toggle switch is connected directly to one terminal of the primary winding 39 of transformer T, the other terminal of which winding is connected to the main i, other than the main l to Which the bus bar Al is connected.
  • the terminals of the secondary winding 40 of the transformer T are connected to the twisted cord conductor 8 leading to the plug 9 in a control outlet l, so that each energization of the primary winding 39 by the code sending device l3 causes energization of control mains 3 and So at a different voltage, with resulting operation of the signal units Iii.
  • One illustrative embodiment of the type of signal unit Ill employed in the system consists of a resonant member 4
  • One lead from the winding 42 is connected to one of the conductors of cable H, while the other lead from the winding 42 is connected to one of a pair of relatively movable contacts 44.
  • the other contact 44 is connected to the other power cable conductor, so that normally there is a gap in the circuit of the winding 42 between the contacts 44.
  • the insertion of the plug !2 of cable ll into the outlet 2 does not energize the winding 42, but merely establishes a condition in which the winding 42 will be energized upon engagement of contacts 44 in response to energization of another winding 45 of the signal unit.
  • the terminals of the winding 45 are connected directly to the conductors of the cord I 3, so that each signal 10 will be operated upon energization of the mains 3.
  • the transformer provides a primary winding 46, one terminal of which is connected to one conductor of the power cable I5, while the other terminal is connected to one of a pair of relatively movable contacts 41.
  • the other contact 41 is connected to the other conductor of the cable I5, so that normally there is a gap in the circuit of the primary winding 46 between the contacts 41. For this reason, the insertion of the plug I6 of the cable l5 in the outlet 2 'does not energize the primary transformer winding 46, but merely establishes a condition in which the winding 46 will be energized upon engagement of the contacts 41.
  • the secondary winding 48 of the booster transformer T is normally deenergized, so that when the plug 28 carried by the conductor cord l8 leading from the terminals of the secondary winding 48 is inserted in the outlet 4a, the auxiliary mains 3a are not energized.
  • the relatively movable contacts 41 in the circuit of the primary winding 46 are under the control of an operating winding 49, the terminals of which are connected to the conductors of the cord l 1. Normally the insertion of the plug l9 carried by the cord IT in an outlet 4 has no effect on the winding 49, so that the whole booster transformer T is normally in a deenergized condition. How ever, upon each energization of the control mains 3 through the functioning of the code sending device B as previously described, the booster transformer T is automatically energized through closure of the contacts 41 in the primary circuit in response to energization of the winding 49.
  • the resulting energization of the mains 3a from the secondary winding 48 occurs practically simultaneously with energization of the mains 3 from the secondary winding 40.
  • all of the signal units l0 operate in unison, whether they be connected between the supply mains I and control mains 3, or between supply mains I and control mains 3a.
  • the number of booster transformers can be increased in order to provide for the energization of additional control mains, without necessitating any alterations in the existing installation of the power wiring. It is possible to install the necessary transformers with the same facility and low cost which characterizes the installation of the code sending apparatus 5 and portable signal units 10.

Description

May 3, 1938.
J. H. WHEELOCK 2,116,255
SIGNAL CODE SENDING SYSTEM 2 Sheets-Sheet 1 Filed March 26, 1952 May 3, 1938.
J. H. WHEELOCK SIGNAL CODE SENDING SYSTEM Filed March 26, 1932 2 Sheets-Sheet 2 Patented May 3, 1938 UNITED STATES PATENT OFFICE SIGNAL CODE SENDING SYSTEM achusetts Application March 26, 1932, Serial No. 601,345
2 Claims.
The present invention relates to an improved signal code sending system for controlling the operation of various kinds of electrical signal devices, calling and locating individuals by code number, as well as the sounding of time and fire alarms being well known uses of such a system.
According to the present invention, there is provided an improved signal code sending system which can be installed with great facility,
at low cost, and which contemplates the employment of portable duo-potential signal units in connection with a portable code sending apparatus. In the operation of the system, the energization of the sending apparatus from a source of given voltage results in dual energization of the signal units at diilerent voltages, one determined by the source, and the other determined by the code sending apparatus. The invention further contemplates the extension of the system to control an indefinite number of signal units without overloading the signal control mains, as energized through the code sending apparatus. The above and other advantageous features of the invention will hereinafter more fully appear from the following description with reference to the accompanying drawings, in which:
Fig.- 1 is a schematic view illustrating the physical appearance of the system as a whole.
Fig. 2 is a wiring diagram showing the electrical connections of the system shown in Fig. 1,
at the time of sending a signal impulse.
Like reference characters refer to like parts in the different figures.
Referring first to Fig. 1, there is illustrated,
schematically, the complete system in which the conductors, or mains I, of a wiring installation are shown as providing a number of outlets 2 at separate points, as in a building, the entire installation being, for example, in accordance with the regulations governing the distribution of current at 110 volts, or higher. The system also comprises control mains 3, preferably in the form of two conductor twisted cord usually employed in the installation of low voltage apparatus, the control mains 3 providing a number of outlets 4, such as ordinary jacks or terminal blocks, disposed throughout the system adjacent to the power outlets. 2. Since all the control wiring may be installed with the same facility and low cost associated with the installation of low voltage apparatus, the low voltage control mains 3 can be extended to various parts of the building in which the system is employed to suit the 55 location of the power outlets 2 already installed,
without necessitating any work in connection with the power wiring installation.
Associated with one pair of adjacent outlets 2 and 4 is a portable code determining and code sending apparatus 5 or" the type shown and de- 5 scribed in Patent No. 1,823,586, issued September 15, 1931 to Herbert Burdick, although obviously the system may be employed in connection with other types of similar apparatus. In Fig. 1 the reference character A designates a code 10 determining, or setting, device cooperating with a code sending device B, in a manner hereinafter described. The apparatus 5 provides. a cable 5 carrying at its end a suitable plug 1 for insertion in a power outlet 2, as well as a length of 15 twisted cord conductor 8 carrying at its end a plug 9 for insertion in the nearest outlet or jack 4. Therefore, when locating the code determin ing and code sending apparatus 5 at any desired point in the system, it is only necessary to place 20 the apparatus 5 adjacent to the nearest pair of outlets 2 .and 4, installation of the apparatus 5 being completely accomplished by inserting its plugs l and 9 in the outlets 2 and 4, as shown. As hereinafter more fully described with refer- 25 once to Fig. 2, the code determining device A and its. associated code sending device B are adapted to be energized and to operate at the voltage of the supply mains I, and the functioning of the code sending device 8 is adapted to intermit- 30 tently energize the conductors of the chord 8 at a voltage different from that of the mains I, as determined by a transformer T, forming part of the apparatus 5. Consequently, with the plug 9 in a jack 4, each energization of the cord 8 is 35 adapted to transmit a signal impulse to the control mains 3, throughout the system.
Associated with other pairs of adjacent outlets 2 .and 4 are a plurality of portable duo-potential signal units 50 of the type fully shown 40 and described in my copending application Serial No. 583,820 filed December 26, 1931. Each signal unit I0 provides a cable ll carrying at its end a suitable plug I2 for insertion in a power outlet, as well as a length of twisted cord conductor I3, carrying at its end a plug I4 for insertion in a jack 4. When installing a signal unit II] at any desired point in the building, it is only necessary to mount the unit adjacent to the nearest pair of outlets 2 and 4, as by means of wall studs Ilia, see Fig. 2; installation of the signal I0 being completely accomplished by inserting its plugs I2 and I4 in the outlets 2 and 4, respectively. With one or more portable signal units Ill connected as illustrated in Fig. 1, operation of the signals is adapted to be controlled through intermittent energiaation of the mains 3 through the code determining and sending apparatus 5, energy for operating the striking or sounding element of each signal unit it being derived from the mains B through the power outlet 2 and the cable ii, as will hereinafter more fully appear.
Associated with still another pair of adjacent outlets 2 and 4 is a portable booster transformer unit T, which provides a cable It carrying at its end a suitable plug it for insertion in a power outlet 2. The booster transformer T also provides two lengths of twisted conductor cord H and i8 carrying at their ends plugs I9 and 20 for insertion in an outlet 4 of the mains 3, and an outlet la of auxiliary low voltage supply mains 3a, respectively. Whenever, in the installation of the system of the present invention in a building, the current carrying capacity of the mains 3 is reached, or it is desired to sectionalize the system, the system can be extended indefinitely by installing one or more booster transformer units T, at any desired points. Obviously, each booster transformer unit T is entirely portable, and its installation is completely accomplished by inserting its three plugs i6, i9 and 28 in one power outlet 2, and in adjacent outlets Q and id of the mains 3 and 3a, respectively. Since as will hereinafter appear, the primary winding of the booster transformer T is adapted to be energized from the supply mains i, only in response to energization of the mains 3, energization of the auxiliary mains 3a from the secondary winding of transformer T is under the control of the code deterrruning and sending apparatus 5. And for the same reason, duo-potential signal units iii, respectively connected between adjacent pairs of power outlets 2 and low voltage jacks Ga, are adapted to operate in unison with the signal units it connected between power outlets 2 and jacks i.
As shown in Fig. 2, the code determining device A consists of a series of parallel bus bars A-i to Aiii inclusive, with the terminals thereof connected to a corresponding number of terminals of codesending device B. The code sending device B comprises a commutator providing a number of groups of contacts C-l to 0-9 inclusive, which are connected to the bus bars Al to Al9, the corresponding contacts of each group being interconnected, as partially indicated. The commutator also provides a brush arm 2i rotatable with a shaft 22, the arm 2i carrying at one end a double brush 23, insulated therefrom, with an outer finger adapted to ride over the surrounding commutator contacts, while an inner finger rides around an annular contact ring 24. The ring 2 2 is connected to one of a pair of spaced contacts 25 adapted to be bridged by a pivoted switch bar 26, operating in unison with the commutator shaft 22, as hereinafter described.
The brush arm 25 carries at its other end a second double brush 2?, insulated therefrom, which provides a pair of brush fingers, the outer one of which bears on an annular contact ring 28 that is permanently connected to the bus bar A- i through commutator contact Cl. The ring 28 provides an insulated gap at 28c, which the finger 2i engages when the device is at rest. The inner brush finger bears on a third contact ring 25 that is connected, in parallel with the bus bar A-l ii, to one terminal of the operating winding of the sending device B. The other terminal of winding 39 is connected to one of the mains I through a pair of contacts 3| normally bridged by the switch bar 26, the other main I being connected to bus bar A--l through cable 6.
As fully shown and described in the aforesaid Patent No. 1,823,586, the winding 30, when energized, is adapted to attract a pivoted armature 32, the free end of which is connected to a crank The crank 33 is connected by gearing 34 to a pawl 35 adapted to engage a ratchet wheel 36 turnable with the commutator shaft 22, each attraction of the armature 32 serving to turn the commutator brush arm 21 through the displacement of one armature contact. Upon deenergization of the operating winding 36, a spring serves to retract the armature 32 and advance the pawl 35 for another step.
An arm 31 carrying the pawl 35 is adapted to operate the switch bar 26 through a toggle connection 38, the bar 26 being thrown from the dotted to the full line position of Fig. 2, upon each attraction of the armature 32 by the winding 36. Obviously, this movement of the bar 26 in step with the advance of the commutator brush arm 2! serves to break the circuit of the winding 36, whereupon the spring serves to retract the armature 32 for another step which takes place upon reclosing of the switch contacts 3 I.
As indicated diagrammatically in Fig. 2, the code determining device A provides a number of keys K movable transversely of the bus bars, fingers serving to determine various code combinations between the keys and bus bars. Normally, with the keys K in non-code determining position, only the bus bar A-l is under voltage from one supply main i, and the code setting device is at rest, with one terminal of the operating inding 38 under voltage from the other main 1 through the closed switch contacts 3 4. Upon depression of a key K, as shown in Fig. 2, a circuit is at once established from the bus bar Al to the bus bar A-lll, through corresponding fingers to the open side of the winding 38, whereupon the armature 32 is attracted to turn the brush arm 2! through one step to engage the first commutator contact C-|. This first step of the sending device B establishes a circuit from one main 5 through bus bar Al, contact C-i and ring 24 to one of the spaced contacts 25 that are bridged by the switch bar 26 upon each step of the brush arm 2!, and this action automatically causes the energization of the control mains 3 and 3a of the system, in accordance with the code, at a voltage different from that of the mains i. To this end, the other contact 25 of the toggle switch is connected directly to one terminal of the primary winding 39 of transformer T, the other terminal of which winding is connected to the main i, other than the main l to Which the bus bar Al is connected. The terminals of the secondary winding 40 of the transformer T are connected to the twisted cord conductor 8 leading to the plug 9 in a control outlet l, so that each energization of the primary winding 39 by the code sending device l3 causes energization of control mains 3 and So at a different voltage, with resulting operation of the signal units Iii.
One illustrative embodiment of the type of signal unit Ill employed in the system consists of a resonant member 4| disposed in operative relation to a winding 42 and armature 43, the arma ture being so disposed that energization of the winding 42 is adapted to cause sounding of the signal. One lead from the winding 42 is connected to one of the conductors of cable H, while the other lead from the winding 42 is connected to one of a pair of relatively movable contacts 44. The other contact 44 is connected to the other power cable conductor, so that normally there is a gap in the circuit of the winding 42 between the contacts 44. Therefore, the insertion of the plug !2 of cable ll into the outlet 2 does not energize the winding 42, but merely establishes a condition in which the winding 42 will be energized upon engagement of contacts 44 in response to energization of another winding 45 of the signal unit. The terminals of the winding 45 are connected directly to the conductors of the cord I 3, so that each signal 10 will be operated upon energization of the mains 3.
Referring now to the booster transformer T, as illustrated in Fig, 2, the transformer provides a primary winding 46, one terminal of which is connected to one conductor of the power cable I5, while the other terminal is connected to one of a pair of relatively movable contacts 41. The other contact 41 is connected to the other conductor of the cable I5, so that normally there is a gap in the circuit of the primary winding 46 between the contacts 41. For this reason, the insertion of the plug I6 of the cable l5 in the outlet 2 'does not energize the primary transformer winding 46, but merely establishes a condition in which the winding 46 will be energized upon engagement of the contacts 41. For the same reason, the secondary winding 48 of the booster transformer T is normally deenergized, so that when the plug 28 carried by the conductor cord l8 leading from the terminals of the secondary winding 48 is inserted in the outlet 4a, the auxiliary mains 3a are not energized.
The relatively movable contacts 41 in the circuit of the primary winding 46 are under the control of an operating winding 49, the terminals of which are connected to the conductors of the cord l 1. Normally the insertion of the plug l9 carried by the cord IT in an outlet 4 has no effect on the winding 49, so that the whole booster transformer T is normally in a deenergized condition. How ever, upon each energization of the control mains 3 through the functioning of the code sending device B as previously described, the booster transformer T is automatically energized through closure of the contacts 41 in the primary circuit in response to energization of the winding 49. Therefore, the resulting energization of the mains 3a from the secondary winding 48 occurs practically simultaneously with energization of the mains 3 from the secondary winding 40. As a result, all of the signal units l0 operate in unison, whether they be connected between the supply mains I and control mains 3, or between supply mains I and control mains 3a. Obviously, the number of booster transformers can be increased in order to provide for the energization of additional control mains, without necessitating any alterations in the existing installation of the power wiring. It is possible to install the necessary transformers with the same facility and low cost which characterizes the installation of the code sending apparatus 5 and portable signal units 10.
I claim:
1. In an electrical signal system, the combination with a series of outlets connected by conductors continuously energized from a source of alternating current, a second and third series of outlets connected by separate conductors of lower current-carrying capacity than the conductors for said first series of outlets, of a portable unitary code determining and sending device connected to an outlet in each of the first and second series and comprising means for transforming current impulses at the source voltage into current impulses at a reduced voltage, with operation of said code sending device causing energization of the second series of outlets at said reduced voltage only during the transmission of signal impulses by said device, in accordance with a code determination, and a portable voltage reducing device connected to one outlet of each of the first and third series and comprising means operable from an outlet of the second series for causing energization of the third series of outlets from the source, at the same reduced voltage of the second series, in response only to energization of the second series of outlets by operation of said code sending device.
2. In an electrical signal system, the combination with a source of power distribution voltage, a plurality of outlets connected thereto, a first circuit of signal wiring of lower current and voltage capacitythan the powercircuit,a plurality of outlets connected to the signal circuit, a transformer having its low voltage secondary winding connected to one of said signal circuit outlets and its high voltage primary winding connected to one of the distribution circuit outlets, a coding device providing normally open contacts in series with the primary winding of said transformer, a second circuit of signal wiring of low current and voltage capacity, a plurality of outlets connected to the second signal circuit, a second transformer having its low voltage secondary winding connected to one of the second signal circuit outlets, and its high voltage primary connected to one of the distribution circuit outlets, and a relay having normally open contacts in series with the primary winding of the second transformer and its operating coil connected to one of the outlets of the first signal circuit, with operation of the contacts of said coding device serving to cause energization of all of the outlets of said first and second signal circuits only during the transmission of signal impulses by said coding device.
JOHN H. WHEELOCK.
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