US966825A - Electrical signaling system. - Google Patents
Electrical signaling system. Download PDFInfo
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- US966825A US966825A US55518110A US1910555181A US966825A US 966825 A US966825 A US 966825A US 55518110 A US55518110 A US 55518110A US 1910555181 A US1910555181 A US 1910555181A US 966825 A US966825 A US 966825A
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- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING SYSTEMS, e.g. PERSONAL CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B25/00—Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems
- G08B25/01—Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems characterised by the transmission medium
- G08B25/04—Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems characterised by the transmission medium using a single signalling line, e.g. in a closed loop
- G08B25/045—Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems characterised by the transmission medium using a single signalling line, e.g. in a closed loop with sensing devices and central station in a closed loop, e.g. McCullough loop
Definitions
- WITNESSES INVENTOR fiflw 2 MW p I n x 7% & WM
- the invention is an electrical signaling system, and consists in the construction hereinafter set forth, whereby an accidental ground occurring in one or more loops of a plurality of loops connected in series in the circuit will not prevent signals being transmitted to a receiving station from any transmitter in any of said loops.
- FIG. 1 is an electrical diagram, showing the invention by conventional symbols.
- Figures 1 and 2 are to be read unitedly, Fig. 1 being placed on the left of Fig. 2.
- Each loop is a transmitter 'T, T, T, each comprising a code wheel H, on the shaft of which is a cam N, having a notch 0 in its rim.
- a switch arm n which is connected to ground as atG, Gr or G
- the code wheel M is at rest, the downwardly bentend of arm n entersnotch 0 in cam N and so opens the ground connection.
- Each wheel M is rotated by any suitable means, released orotherwise controlled by the operator when a signal is to be sent, and, in rotating, said wheel makes and breaks circuit between the 'spring arms m, m, in the usual way.
- circuit with switches (Z, c and contacts 1, 2 are a local battery Land glow lamps P, Q, r ⁇ the whole located at the receiving station i and constituting a translating device for sig- ,,nals coming over the line from transmitters T,-T, T
- the magnet F has two coils, and
- the magnet B controls its switch I) to make and break circuit at 4 and 5 and its switch I) break circuit at 7 8, 9, 10.
- the magnet Uv has its switch lever formed of a number of mutually insulated sections u, U u", u, u
- the section a closescontacts 'at 11, 12: the section W, at 13, 14, 15: the section u at 16, 17, 18: the section a at 19, 20, and the section/u, at 21, 22, 23, 2 1.
- each loop I, II, III Associated with each loop I, II, III is a thermostatic circuit closer.
- Each of said circuit closers consists of a thermostatic bar S, S S, which may be made of two metals, as steel and brass, and supported at one end.
- On each bar are two heating coils 25 and 26. When one or the other or both of the coils on a bar are heated, the bar bends to close and open certain circuits.
- the switches controlled by each bar S,,S S are alike, so that the description of the set governed by bar S applies to allthree- On the free end of bar S are mounted the switches s, 8 8, s insulated from one another and from the bar.
- switch 8 On switch s is mounted a switch 8 which is insulated from switch 8 ⁇ Vhen the bar S is cool, no-current then passing through the coils 25, 26, the switch s closes circuit at 2'1 the switchs at 28; the switch 8', at 29, and, the switch s at 30. ⁇ Vhen the bar is heated by the passage of current throughone or both of the coils 25, 26, as
- switch 8 opens circuit at27: s opens circuit at- 28 and closes circuit at 31: 8 opens circuit at 29 and closes circuit at 32: 8* opens circuit at 30, and s closes circuit at 33.
- the magnet V like the magnet F, has two coils, and when one over' balances the other, controls its switch 4) to close at 34, a local circuit including a bat- A thermostatic bar. S, similar to bars S, S S but havlng one tery L and lamp P.
- heating coil 35 when heated bythe passage of current, closes contact at 36.
- switch a contact 20, wire 43, other coil of v transmitter 'T, there is constant connection to ground G, thus energizing the magnet F to close contact at 3, which pointis connected by wire 45 and junction 46 to nongrounded pole'of source A.
- Two branches are thus established from switch f, namely, (1) through magnet H to ground G (2) by wire 47 through coil 35 of thermostatic bar S to ground (ii. Magnet'H being energized, opens circuit at 7 and 9, and closes circuitat 8 and 10.
- the coil of barS is nottraversed by a current for a sufficient period of time to cause said bar to close circuit at 36.
- magnet H should be made with sufiicient lag so as not to respond to the signal taps.
- magnet B which is normally energized is, caused to fail, so that its switches 12, I) open circuit at contact 4 and close circuit at contacts 5 and 6.
- Two leads from the non-grounded pole of source A now exist as follows: (1) from source A, to magnet D, one coil of magnet F, wire .37, wire 38,.
- Magnet J now fieing energized by a reverse current swings its switch j to close circuit at contact 'source A: thus energizing magnet B and restoring the metallic circuit as originally described. Magnet B is given suificient lag so that it will not be caused to fail by the momentary interruptions due to the opera-' tion of. the transmitters; nor until after its circuit has been opened for some predetermined periodof time.
- thermostatic bars S, S S are normally cold, and that their heating coils are thenshort-circuited by. the switches a", 24",; etc., controlled by magnet U.
- coil 25 is short-circuited as follows: from coil 25, to switch 8, contact 27,
- loop I individually, the lead in each loop .being' the sameas now to be described-in connection with loop I.
- the short circuit of loop I progeeds from junction point 63 on one side of loop I, by wire 61, to contact 22, switch 115', contact 21, wire 62, wireij59, to
- These two leads are tied together by the crossing from junction 63 by wire (31 to contact 22 and switch 10 In this case both heat coils 25 and 26 will become heated.- causing the bar S, already described, to open circuit at 2T, 28, 29 and 30, and close circuit at 31, 32, 33.
- the result then is (1) to cut loop I and the transmitter T therein out of the system and connect it with magnet V and battery L, one pole of which battery is grounded at G.
- Magnet V is then balanced, but when the transmitter T operates, it responds to the tap signals which are translated at the receiving station by the lamp P, battery L then maintaining sufficient current through coils and 26 to keep them heated. so that bar Sremains in its operated position.
- Another result is (2) to make a short circuit from junction point 63 on wire 37 to point- 64 on wire 60, which proceeds as follows: from junction point (33, by wire 37, wire 57, switch 3 contact 3?), wire (30 'to point 64.
- the purpose of this short. circuit is to make the metallic circuit continuous after loop I hasbeen removed therefrom. Of course, the removal of the ground at point Z in loop I from the tem causes magnet F again to become balanced, opening circuit at 3, which causes magnets H and U to fail.
- magnet U acts to break all the loop short circuits and to establish the short circuits around the heating coilseXcept-the short circuits around the'eoils of bar S in loop I which are open because of the open contacts at 27 and 30.
- Magnet H by means of magnet J and magnet B, as already described, reestablishes the original metallic circuit. The net result of the whole then is,
- the object of the resistances (36, (57 connected with magnet V is approxin'iately to equalize the flow of current over the members a, a to the ground at Z, so as to insure the neutralization of magnet V when the transmitter is not operating.
- metallic circuit including a plurality of loops in series, a groundconnection from each of said loops, a transmitter in each of said loop ground connections, translating means in said circuit operated by each of said transmitters, a separate translating means in local circuit, means operating upon the occurrence of an abnormal ground in any one of said loops for cutting said 100.
- a metallic circuit including a plurality of loops in series, a ground connection from each of said loops, a transmitter in each of said loop ground connections, translating means in said circuit operated by each of said transmitters, a separate translating means in local circuit, means operating upon the occurrence of an abnormal ground 1n any fractional number of said loops for cutting said loops out of circuit, means for con.- necting said loops in local circuit with said separate translating means, means for closing the gaps in the metallic circuit due to the removal therefrom of the grounded loops, and means operating upon v the removal of said. abnormal grounds for restoring the original metallic circuit.
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Description
A. GOLDSTEIN.
ELECTRICAL SIGNALING SYSTEM.
APPLICATION FILED APB.13. 1910.
965,8Q5n Patented Aug. 9, 1910.
2 SHEETS-SHEET 1.
WITNESSES: INVENTOR fiflw 2 MW p I n x 7% & WM
7 MATTORNEY.
A. GOLDSTEIN.
ELECTRICAL SIGNALING SYSTEM.
APPLIOATION FILED APR. 13, 1910.
2 SHEETS-SHEET 2.
Patented .Aug. 9, 1910.
MNVENTOR m flu, ATTORNEY.
UNITED STATES PATENT OFFICE.
ALBERT GOLDSTEIN,' OF NEW YORK, N. Y.', 'ASSIGNOR TO INTERNATIONAL ELECTRIC I .PBOTECTION COMPANY, A CORPORATION OF NEW YORK.
ELECTRICAL SIGNALING SYSTEM.
' Specification of Letters Patent. Patented Aug, 9, 1910,
Application filed April 13, 1910. Serial No. 555,181.
. a specification.
The invention is an electrical signaling system, and consists in the construction hereinafter set forth, whereby an accidental ground occurring in one or more loops of a plurality of loops connected in series in the circuit will not prevent signals being transmitted to a receiving station from any transmitter in any of said loops.
The accompanying drawing is an electrical diagram, showing the invention by conventional symbols. Figures 1 and 2 are to be read unitedly, Fig. 1 being placed on the left of Fig. 2.
Three loops I, II, III are here shown in series circuit with the source A of current which is grounded at G. In each loop is a transmitter 'T, T, T, each comprising a code wheel H, on the shaft of which is a cam N, having a notch 0 in its rim. Bearing on the cam is a switch arm n which is connected to ground as atG, Gr or G When the code wheel M is at rest, the downwardly bentend of arm n entersnotch 0 in cam N and so opens the ground connection. Each wheel M is rotated by any suitable means, released orotherwise controlled by the operator when a signal is to be sent, and, in rotating, said wheel makes and breaks circuit between the 'spring arms m, m, in the usual way. The
are shown at a a, a a and at a pso that all .of the parts shown on the right of the line w, w,in the drawing are located at the re- 1 ceiving station, to which the signals are sent a. over the line vconductors from the several transmitters T, T, T
The magnets D and El-respectively control their switches d, e to make and break local circuit at 1 and 2. In
,circuit with switches (Z, c and contacts 1, 2 are a local battery Land glow lamps P, Q, r {the whole located at the receiving station i and constituting a translating device for sig- ,,nals coming over the line from transmitters T,-T, T
, when one over-balances the other, controls #its switch 7 to make and break circuit at 3.
The magnet F has two coils, and
The magnet B controls its switch I) to make and break circuit at 4 and 5 and its switch I) break circuit at 7 8, 9, 10. The magnet Uv has its switch lever formed of a number of mutually insulated sections u, U u", u, u
The section a closescontacts 'at 11, 12: the section W, at 13, 14, 15: the section u at 16, 17, 18: the section a at 19, 20, and the section/u, at 21, 22, 23, 2 1.
Associated with each loop I, II, III is a thermostatic circuit closer. Each of said circuit closers consists of a thermostatic bar S, S S, which may be made of two metals, as steel and brass, and supported at one end. On each bar are two heating coils 25 and 26. When one or the other or both of the coils on a bar are heated, the bar bends to close and open certain circuits. The switches controlled by each bar S,,S S are alike, so that the description of the set governed by bar S applies to allthree- On the free end of bar S are mounted the switches s, 8 8, s insulated from one another and from the bar. On switch s is mounted a switch 8 which is insulated from switch 8 \Vhen the bar S is cool, no-current then passing through the coils 25, 26, the switch s closes circuit at 2'1 the switchs at 28; the switch 8', at 29, and, the switch s at 30. \Vhen the bar is heated by the passage of current throughone or both of the coils 25, 26, as
the case may be, then switch 8 opens circuit at27: s opens circuit at- 28 and closes circuit at 31: 8 opens circuit at 29 and closes circuit at 32: 8* opens circuit at 30, and s closes circuit at 33. The magnet V, like the magnet F, has two coils, and when one over' balances the other, controls its switch 4) to close at 34, a local circuit including a bat- A thermostatic bar. S, similar to bars S, S S but havlng one tery L and lamp P.
" The metallic circuit proceeds asfollows: from non-grounded pole of source A, to
magnet D,- one coil of neutral magnet F,
switch a, contact 20, wire 43, other coil of v transmitter 'T, there is constant connection to ground G, thus energizing the magnet F to close contact at 3, which pointis connected by wire 45 and junction 46 to nongrounded pole'of source A. Two branches are thus established from switch f, namely, (1) through magnet H to ground G (2) by wire 47 through coil 35 of thermostatic bar S to ground (ii. Magnet'H being energized, opens circuit at 7 and 9, and closes circuitat 8 and 10. Inasmuch as magnet F is not retarded in its response to the taps of the signal from transmitter T, the coil of barS is nottraversed by a current for a sufficient period of time to cause said bar to close circuit at 36. On the other hand, magnet H should be made with sufiicient lag so as not to respond to the signal taps. By reason of the opening of the circuit at 7, magnet B which is normally energized is, caused to fail, so that its switches 12, I) open circuit at contact 4 and close circuit at contacts 5 and 6. ,Two leads from the non-grounded pole of source A now exist as follows: (1) from source A, to magnet D, one coil of magnet F, wire .37, wire 38,.
contact 11, switch a, contact 12, wire 39, contact 27, switch 8, and line member a-of loop I through trans-nutter T to ground G. (2) from source A, to junction X, magnet E, switch it, contact 10, wire 48,- contact 8, switch it, other coil of magnet F, wire 43,
contact 20, switch a", contact 19, wire 42,"
through the switches controlled by thermostatic bars 5 and S in loops III and II to Wire 41, contact 15, switch 20 contact 13,
one coil of magnet F, through loops I, II, III successively, by wire 43, to other coil of magnet F, switch h, contact 7, wire 44, switchb,contact 5, wire 49, polarized magnet J, wire 50, to junction Y. Then, from junction Y, by wire 51, to switch it, contact 9,. wire 52, resistance 53, switch b,.contact 6, to rounded pole of source A. Magnet J now fieing energized by a reverse current swings its switch j to close circuit at contact 'source A: thus energizing magnet B and restoring the metallic circuit as originally described. Magnet B is given suificient lag so that it will not be caused to fail by the momentary interruptions due to the opera-' tion of. the transmitters; nor until after its circuit has been opened for some predetermined periodof time.
I will now describe the operation of the system under abnormal condition of a ground occurring'in any one of the loops say, for example, at Z in member a of loop I. The immediate effect of the ground is to unbalance magnet F, which closes circuit at 3. .This energizes magnet H, with the results already described. Because now the ground is kept on, the current can heat coil 35 of bar S, causing the free end of said bar to close contact at 36, thus establishing the following circuit: from non-grounded pole of source A, to unction 46, wire 45,
contact 3, switch f, wire 47, bar S, contact- 36, magnet U to ground G". Magnet U thus becomes energized, opening contacts 11, 12, 13,14, 15, 16, 17, 18, 19 and .20, and
closing contacts 21, '22, 23, -24. It is. now
to be especially noted that the thermostatic bars S, S S are normally cold, and that their heating coils are thenshort-circuited by. the switches a", 24",; etc., controlled by magnet U. Thus in the case of barxS, for example, coil 25 is short-circuited as follows: from coil 25, to switch 8, contact 27,
as stated, the contacts 21, 22, 23, 24. :Tliese contacts short-circuit the three loopsrI, II,
III individually, the lead in each loop .being' the sameas now to be described-in connection with loop I. The short circuit of loop I progeeds from junction point 63 on one side of loop I, by wire 61, to contact 22, switch 115', contact 21, wire 62, wireij59, to
junction 64 on the other side ofloop I.-
Two leads are thus established from nongrounded pole of source A, to thetgrou nd at Z, as follows: (1) from source-1 A, to magnet D, one coil of magnet F, wire 37, wire 57 ,contact 28, switch .9 heat :coil 25, line member a of loop I to Z. (2),; -From It will be evident,-
source A, to junction X, magnet E, wire 51, switch h, contact 10, wire 48. contact 8,
switch b, other coil of magnet F, wire 43,
Wire 65, contact 23, switch '11., contact 21, wire 62, wire '59, wire 60, contact 29, switch 8 heat coil 26, line member a of loop I, switches in and m. of transmitter T and line member a of loop I to Z. These two leads are tied together by the crossing from junction 63 by wire (31 to contact 22 and switch 10 In this case both heat coils 25 and 26 will become heated.- causing the bar S, already described, to open circuit at 2T, 28, 29 and 30, and close circuit at 31, 32, 33. The result then is (1) to cut loop I and the transmitter T therein out of the system and connect it with magnet V and battery L, one pole of which battery is grounded at G. Magnet V is then balanced, but when the transmitter T operates, it responds to the tap signals which are translated at the receiving station by the lamp P, battery L then maintaining sufficient current through coils and 26 to keep them heated. so that bar Sremains in its operated position. Another result is (2) to make a short circuit from junction point 63 on wire 37 to point- 64 on wire 60, which proceeds as follows: from junction point (33, by wire 37, wire 57, switch 3 contact 3?), wire (30 'to point 64. The purpose of this short. circuit is to make the metallic circuit continuous after loop I hasbeen removed therefrom. Of course, the removal of the ground at point Z in loop I from the tem causes magnet F again to become balanced, opening circuit at 3, which causes magnets H and U to fail. The failure of magnet U acts to break all the loop short circuits and to establish the short circuits around the heating coilseXcept-the short circuits around the'eoils of bar S in loop I which are open because of the open contacts at 27 and 30. Magnet H, by means of magnet J and magnet B, as already described, reestablishes the original metallic circuit. The net result of the whole then is,
that transmitter T in grounded loop I sends itssignals t'o lamp 1 while transmitters T and T continue to send their signals over the metallic circuit to lamps I and Q as before. The effect, therefore, otan accidental ground on any loop is to cut that loop out of the system and toconnect its transmitter to the special receiving appara: tus operating lamp 1 and to close the gap in the metallic circuit due to this removal of the grounded loop, so that the transmitters in the remaining unimpaired loops can continue sending their signals over the metallic circuit, as before, to operate lamps P and ,0. If only one loop is grounded, that loop is cut out: if two loops are individually grounded, both are cut out, and so for any number of loops, the grounded loops being automatically removed. and the metallic circuit reestablished for whatever loops may remain;
The object of the resistances (36, (57 connected with magnet V is approxin'iately to equalize the flow of current over the members a, a to the ground at Z, so as to insure the neutralization of magnet V when the transmitter is not operating.
I claim:
1. The combination of a source of cur-' rent, a grmind connection at one polethereof, a metallic circuit including a plurality of loops in series, a ground connection from each of said loops, a transmitter in each of said loop ground connections, translating means in said circuit operated by each of said transmitters, means operating upon the occurrence of an abnormal ground in any one of said loops for cutting said loop out of circuit, and means for closing the gap in the metallic circuit due to the removal therefrom of the grounded loop.
2. The combination of a source of current, a ground connection at one pole thereof, a metallic circuit including a plurality of loops in series, a ground connection from each of said loops, a transmitter in each of said loop ground connections, translating means in said circuit operated by each of said transmitters, means operating upon the occurrcnceof an abnormal ground. in any fractional number of said loops for cutting said loops out of circuit, and means for closing the gaps in the metallic circuit due to the removal therefrom of said grounded loops.
3. The combination of a source of current. a ground connection at one pole thereot, a metallic circuit. including a plurality of loops in series, aground connection from each of said loops, a transmitter on each of said loop ground connections, translating means in said circuit operated by each of said transmitters, a separate translating means in local circuit, means operating upon the occurrence of an abnormal ground in any one of said loops for cutting said loop out of circuit, and means for connecting said cut out loop to said separate translating means.
4. The combination of a source of current, a ground connection at one pole thereof, a metallic circuit including a plurality of loops in series, a. ground connection from each of saidloops, a transmitter in each of said loop ground connections, translating means in said circuit operated by each of 'cut out loop in local circuit with said separate translating means, andmeans for closing the gap in the metallic circuit due to the removal therefrom of the grounded loop.
6. The combination of a source of current, a ground connection at one pole thereof, a metallic circuit including ,a pluralit of loops in series, a ground connection from each of said loops, a transmitter in each of .said loop ground connections, translating means in said circuit operated by each of said transmltters, a separate translating means in local circuit, means operating upon the occurrence of an abnormal ground nany fractional number of said loops for cutting said l'oops out of circuit, means for connecting said loops in local circuit withsaid' separate translating means, and means for closing the gaps in the metallic circuit due to the removal therefrom of the grounded loops.
'7 The combination of a source of current, a ground connection at one pole thereof, a
metallic circuit including a plurality of loops in series, a groundconnection from each of said loops, a transmitter in each of said loop ground connections, translating means in said circuit operated by each of said transmitters, a separate translating means in local circuit, means operating upon the occurrence of an abnormal ground in any one of said loops for cutting said 100.
- out of the circuit, means for connecting sai cut out loop in local circuit with said se arate translating means, means for closing the gap in the metallic'circuit due to the removal therefrom of the grounded loop, and means operating u on the removal of said abnormal ground or restoring the original metallic circuit.
8. The combination of a source of current,
a ground connection at one pole thereof, a metallic circuit including a plurality of loops in series, a ground connection from each of said loops, a transmitter in each of said loop ground connections, translating means in said circuit operated by each of said transmitters, a separate translating means in local circuit, means operating upon the occurrence of an abnormal ground 1n any fractional number of said loops for cutting said loops out of circuit, means for con.- necting said loops in local circuit with said separate translating means, means for closing the gaps in the metallic circuit due to the removal therefrom of the grounded loops, and means operating upon v the removal of said. abnormal grounds for restoring the original metallic circuit.
In testimony whereof I have afiixed my,
signature in presenceof two witnesses. ALBERT GOLDSTEIN.
Witnesses:
Gnn'raunn T. PORTER, MAY T. MOGARRY.-
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US55518110A US966825A (en) | 1910-04-13 | 1910-04-13 | Electrical signaling system. |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US55518110A US966825A (en) | 1910-04-13 | 1910-04-13 | Electrical signaling system. |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US966825A true US966825A (en) | 1910-08-09 |
Family
ID=3035218
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US55518110A Expired - Lifetime US966825A (en) | 1910-04-13 | 1910-04-13 | Electrical signaling system. |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US966825A (en) |
-
1910
- 1910-04-13 US US55518110A patent/US966825A/en not_active Expired - Lifetime
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