US1375059A - Signal system - Google Patents

Description

A. E. MEYER.

SIGNAL SYSTEM.

APPLICATION FILED FEB. II. I918.

Patented Apr. 19,- 1921.

series.

Ailiihii ALFRED E. MEYEE, OF CINCINNATI, OHIO.

SIGNAL sYscrEM.

Specification of Letters Patent.

Patented Apr. 19, 1921.

Application filed February 11, 1918. Serial No. 216,561.

T 0 all whom it may concern Be it known that I, ALFRED E. MEYER, a citizen of the UnitedStates, and residing at Cincinnati, in the county of Hamilton and State of Ohio, have invented a new and useful Improvement in Signal Systems, of which the following specification is a full disclosure. i

My invention relates to an electric system for the transmission of signals as of central station alarm service or watchmens time recording. V

The invention has for an object the provision of a signal system with a metallic service line extending from a centralor receiving station to the transmitting stations and back to the receiving station, with the transmitters of said transmitting stations in series circuit connection with said metallic line, and with a ground connection under automatic control dividing the transmltting stations into a plurality of service or signal transmitting branch lines, each with an earth return circuit, whereby the advantages of a continuous metallic. line between the receiving and. transmitting stations is available. 7

Another object of the'invention is to provide a plurality of signal systemsfor central station alarm service, each system comprising receiving apparatus and transmitting I apparatus connected by ametallic partial circuit line and ground return, and a line controlling device in connection with the metallic lines of said systems for establishing the earth return for said metallic lines, automatically operated bya changein current strength from the normal for establishing a metallic. line and receiving station connection between the metallic lines of the different systems in the event of an impairment to one of said metallic service lines.

Another object of the invention is'to connect the ends of central station metallic partial signal circuit lines, with a circuit controlling device uninfiuenced by the normal current strength carried by the circuit lines, but responsive to a definite increase of current strength for bringing a portion of an impaired service line into communication with the central station over and in direct circuit with a second normal service line, and for reestablishing the independence of the service lines when the'impairrnent to the one has been rectified. p

1 Other features and objects of the invention, combination of elements, and arrangement of parts w1ll be more fully hereinafter described, and more particularly pointed out in the claims. convenient embodimentgis typically. illustrated in the accompanying drawing, forming a part hereof, and in the drawing like characters of reference denote corresponding parts throughout the several views, of which:

Figure 1 is ardiagrammatic view of an electric signal system with the various appliances connected in electric circuit under a normal condition.

Fig. 2 is a diagrammatic view of a modified form of wiring and'circuit controlling apparatus.

As the system primarily is contemplated for a central station night watch time recording or fire alarm signal service, the description will generally be confined to this particular field of use, although as to certain aspects other kinds of electric signal systems are comprehended.

A closed metallic circuit for the trans mission of signals may be designated as a continuous line starting froma central station or receiving point, including in series the various and diii'erent transmitting devices embraced in the system and returning'to the central station; 1 An open earth return circuit is utilized in connection with the metallic line for transmitting trouble signals. This assures normally thetransmission'otwtwo signals usually distinctive in character from each point or transmitting device, and provides a means for maintaining the system under test, and also a means for transmitting a single or ground circuit signal in the event of a break in the metallic line, dividing the transmitting devices of the series with those on one side of the break using one portion of the metallic line, and those on the opposite side of the break using the other portion of said metallic line. Limitations as to the number of transmitting devices under such system are placed by insurance underwriting authorities, as a precautionary measure.

' With my system the advantages above noted in a complete or all closed metallic circuit'system are maintained, but the metallic line,when conditions are normal, is divided into independent'service lines, each for successively transmitting signals over two independent circuits both having earth return, so thatin single loop line, the

.requirea difierent or greater current inorder to be attracted by their magnet coils over those of relays 1, 2. Thus, under a closed circuit and normal line, relays 1, 2, will stand with their armature levers attracted to their magnets or closed while relays l", 2, will stand with these armature levers retracted from their magnets or open. 3 indicates a generator, or source of electric energy supply, and 4:, 5, tap key switches for respectively cutting out the relays of the different service lines, and located at the service or receiving station.

The relays represent those of commercial I type used in pen recorders, and in general comprise a magnet coil 6, armature lever 7, which as a pole switch, in its to and fro motion, alternately contacts with the relatively opposite terminals 8, 9, for making and breaking electric circuits.

The armature lever is held under tension by a spring 10, which in all relays is arranged, so that i'ts tension may be adjusted or varied.

The tap key switches at and 5 are the duplicate of each other, and each comprises a key lever 11, swung between two relatively opposite terminals 12, 13, and under tension by a spring 1a to normally engageor contact with one terminal in this instance terminal 12.

15,15, 15, represent break wheel signal transmitting devices ot one group located at different service points from the service or central station, and may be designated as night watch boxes as of a type of construc tion, wherein the break wheel is manually started or set in motion by an operator turning a key, and 16, 16, 16, signal. transmitting devices oi? a second group. The number for either group is optional, and in a general way they may be described as switch devices operated by a break wheel, so that one transmitting device is capable oi transmitting a signal distinctive over the signal of the other signal transmitting devices. matic, as for automatic fire alarm service. For the present purpose, each of the tran mitting devices comprises a break wheel 17 flexible switch fingers 18, 19 and 20, each finger having a contact or terminal point Their operation may also be autoengaging with the contact point ofthe ad jacent linger for completing the circuit, through the connected fingers. The finger 18 is extended to engage with the break wheel 17, and its contact point with a registering contact point projected from finger 19, and likewise finger 19 arranged for electrically connecting with the finger 20.

The break wheel 1'? is notched or toothed for a proper finger control to transmit in each revolution a definite signal' Each break wheel, under a normal condition of the system rests with the break finger 18 engaging its periphery at a point which will hold the contact point of said finger in engagement with the contact point ofan adjacent finger 19 for completing a partial line circuit through'said fingers l8 and'19. A

third break finger 20, adjacent the break finger 19 normally has its contact point free from engagement with the finger 19 so as not to be in electric circuit therewith. Finger 20 of each call box connects with a wire 21 leading to a ground terminal 22.

At a. terminal or meeting point of the metallic service lines 43,'each service line' including in series wiring the fingers 1'8 and 19 of each call box or signal transmitting device, a circuit controlling device is provided and operated from the central station over one of the service lines it a break occurs in the other. The controlling device coupling such portion of the broken service line between the point'of break and circuit controlling device to the other intact service line to bring it in circuit with the central station, until the line is rectified.

The circuit controlling device, as shown in F 1, comprises a plurality of flexible fingers 25, 26, 27, and adjacent one another, each mounted .upon an insulator base or support. l ingers 25 and 27 are connected together to move as a'unit but electrically insulated from one another, with finger 27 having a contact point adapted to connect or engage 28. Fingers 25 and 26 are arranger to connect with each other through contact points which normally are engaged. 29 indicates a trip lever actuated by a spring 30 after the lever has been tripped by an armatrouble of broken service ture 31 when attracted to its magnet 32. 33

and 3 1 each indicate a resistance.

I .l-Vz'ring diagram.

The circuits to and from the various terminals of the devices above described may be traced as follows: I

Commencing at the generator or source of electric supply 3, one end of a wire or lead 35 connects with one pole oi the gen erator, and its opposite end connects with the earth at 36. A wire 37 connects to the opposite poleof the generator as a main para contact point of finger tial circuit metallic lead line for the various service lines or branches. Each branch or service connects with the main lead line 8? at the central station and may be said to consist of a station line and a field line normally connected by afitap key switch 4. As the different series lines are the duplieate of each other, it is only necessary to de scribe one in detail, each however running from the central station and terminating at a common point'at which the field circuit controller is located so as to connect therewith. r 1

Therefore describing the service line, which includes the relays 1, 1 and transmitting device or call boxes 15, it may be said to comprise a station service line 38. The station service line 88 connects at one end with the main lead line 37 and itsoppo site end with the contact terminal 12 or the tap key switch 4. This station service line '88 includes in series circuit connection therewith a resistance 40, and relays 1 and 1. The metallic circuit line 39 connects at one ground circuit from finger direct to the central station ground terminal, cutting out the resistance 33, causing a rise in the current sunicient to fully energize the windings of the relay 1 The armature lever of the relay 1 is operated for a primary signal indication orrecording. The break wheel continuing for afinger control breaks the connection or" fingers 18, 19, which breaks 01' opens the circuit causing the magnet winding of relay- 1 to become deenergized fora secondary signal indication on record. Such make and break, in a particular order,

commencing and continuing for a double indication or recording of adistinctive signal.

The armature 7 of the relay 1 for the primary si 'nal is operated or vibrated by variations in the current strength through an operating call-box. The armature is attracted to its magnet when the circuit is end with the key lever '11 of thetap key switch 4 and under normal line condition includes in series'circuit connection the fin gers' 18, 19, of each transmitting device or call box 15 and'conn'ects with the resistance 33 at its opposite end. From the resistance, metallic circuit line continues through a wire 42 connecting with a terminal e3 as a common terminal for the various metallic I circuit lines ofthe different service branches.

The common terminal 43 connects with the one pole of the windings of the magnet 82 and the opposite pole of said magnet windings connect with a wire 14:, which extends to and connects with the finger of the circuit controlling device. The circuit thus continues from finger 25, through finger 26, wire to the ground 46. The constant resistance in the service line reduces the current flowing.therethro'ugh preventing the full energization of the magnet windings of relay 1 and magnet 32 of the circuit controller device or anexcitation sufiicient to attract their respective armatures. Thus closed signal circuits are maintained from the source of electric supply through the said devices insaid service lines 38, 89, re-

established through the break fingers 18 and 20 of the operating call-box, connecting the field line or wire 89' and ground return, to which the finger" 20 connects. This shunts the resistance 88 resulting in an increase in current strength to relay l andanincrease in the degree of its magnet pull," which overcomes the spring normally holding the armature away from its magnet. instantly upon breaking the contact beytweenthe fingers 18 and 20, the circuit is reestablished through the resistance 33, lowering the current strength and thereby the pull of the magnet of relay 1, making the spring force prevail over the pull of the magnet to swing the armature to its retracted position; Thearmature of the relay 1 is normally held attracted to its magnet and for receiving the secondary signals is vibrated by making and breaking the circuit turning through'the earth from the ground terminal 16 to the generator ground termical 36. V

For the transmission of a call signal, it may be assumed that the break wheel 17 of a given coil box 15 is rotated, and depending upon its particular signal indicating cut, will, sem'mtc'm, move the finger 18 to bring the contacts of all fingers 18, 19 and 29 into engagement This short circuits or shunts the portion. of the metallic circuit line from said call boxto the ground connection of the circuit controlling device at the end f e line an C mpletes a partial movement of finger 18 away from finger 19.

Now assume that a break or ground occurs in the circuit line 39, say ata point indicated by the cross, which would be observed at the central station,"a break affecting relay 1, which would becoine deener gized, releasing its armature lever showing that the condition of the field line 39 has been disturbed, a break in the circuit would leave the transmitting devices or call boxes 1'5, 15, beyond such break out of connection with the central station. The operator would thereupon immediately throw the tap key 5 to connect line 39 in circuit with the ture lever 31, tripping the trip lever 29,

which will close or connect fingers 27, 28, and break fingers 25 and 26, thus connecting such portion of the field service line 39 beyond'the break X in circuit with the field service line 39, as follows:

Commencing with the terminal 50 at the I end of the field service line 39, through a wire 51, connecting with the finger 28, through said finger 28 connected therewith through said finger 27 and wire 52, connecting with the terminal 53 at the end of the field service line 39, which cuts out the resistance 33 and 34;, coupling such broken portion or" the field service line 39 with the central station, through asecond branch. After the trouble in the service line 39 has been corrected, the trip lever 29 is manually swung and engaged with the armature lever 31, breaking the circuit connection between fingers 27 and 28, and again establishing a circuit connection between fingers 25, 26. The service line for relays 1 and l is likewise provided with a shunt line 54, connecting with the main lead line 37 and adapted to be thrown-in circuit with the field service line 39 by the tap key 4:, to out out the relays 1 and 1 and resistance 10 for operating or energizing the windings of magnet 32 in case of a break in the field service line 39 to throw such portion of the line broken from communication with the central station, in circuit with the field service line 39. A momentary operation of the tap keys a and 5 is only necessary for energizing the magnet 32, and to transfer a portion of one service line in circuit with a second service line, so as not to interfere with the sending of signals from the call boxes in communication with the relays of the first branch, or vice versa, as the case may be. Thus, a signal from all the call boxes can be received at the central station. In the diagram, Fig. 2, the circuit controls ling or transfer device represents a modified form adapted to be reset from the central station, and in detail comprises the following parts The two service branch lines 39-39% as in Fig. 1,. lead to the circuit controlling or transfer device, with service line 39 connecting with one pole of a magnet winding 32, 7

its opposite pole connecting by a wire to a finger 61, normally as an open line circuit.

The wire 60 through abranch connection connects with the resistance 33, thence by a wire 62 connects with the circuit. breaking sector 63 mounted upon a shaft 64: of an'ordinary clock movement commonly used in fire or alarm call boxes. A finger 65 normally engages the circuit breaking sector 63 and is grounded. The second service line 39 connects with one pole oi a magnet winding 32 The opposite pole of said magnet winding 32 is connected to a wire 66 which leads and connects to a break finger 67 adapted to engage the circuit breaking sector 63. line 66 connects by a branch with the resistance 34% at one side orpole, while the opposite pole of the resistance connects with the wire 62 leading to the circuit breaking sector 63. 68 represents an armature for tripping the clock movement escapement 69 for releasing the circuit breaking sector 63 when either one of the magnet windings 3232 have been fully energized to attract the armature 68. .Under normal conditions of the system, the circuit in the service line 39 is closed from the central station through said line magnet 32, resistance33, wire 62, circuit breaking sector 63, break finger 65, returning through the ground. Thus, the resistance 33 is included in the circuit, which reduces the potential to a degree preventing lull energization of the magnet winding 32. When it is necessary to transfer or 0011- 7 nect the serviceline 39 with the service line 39, a proper tap key at the central office is operated to cut out the resistance and relays connected in the service line 39, thus fully energizing magnet 32 tripping the escape ment and permitting the circuit breaking sector to rotate one-half oi the revolution to break the circuit connection between fingers 65 and circuit breaking sector 63, .and connect the breaking fingers 61 and 67 with the circuit breaking sector 63. In such position of the circuit breaking sector63 the service line 39 will connect or be coupled to the service line 39, through the magnet winding 32, wire 60, contact finger 61, circuit breaking sector 63, contact finger 67, wire 66, magnet windings 32-"% to service line 39*. Under such conditions theresistance 33 and 34 will be cut out. The magnet windings 32and 32 remain constantly in circuit with the service line communicating with the central office for test and reset purposes, which, as soon as the line conditions have been corrected, either one of the tap keys may be operated to throw in a higher potential in the service lines energizingthe magnets 32-32 tripping the escapement for a sec- 0nd half of revolution of circuit breaking sector 63, permitting it to break connection with the fingers 6167, and reestablishing its connection with the break fingers 65. Thus, the service lines may be connected for signal transmission over one of them at ing one pole thereof connecting with said.

metallic line and the opposite pole grounded, a resistance interposed in said line, a ground connection between the ends of the resistance dividing said metallic line into independent service circuits having an earth return, a relay for each service line in circuit therewith and connected in series circuit connection with said metallic line, and a circuit controller for shunting said resistance and cutting out the earth return.

2. In a signal system, comprising a me tallic line, a source of current having one pole thereof connecting with said metallic line and the opposite pole grounded, a resist- ,ance interposed in said line, signal transmitting apparatus in circuit with said me tallic line, a grounded connection interposed in said resistance between the ends thereof for dividing said metallic line into independent circuits, each having an earth return, a relay for each service line in circuit therewith, and electro-magnetic means having its magnet windings normally in circuit with said independent service lines for shunting said resistance and establishing a unitary metallic line.

3. In a signal system, comprising a metallic line having its ends connecting with a common pole of a source of electric current, a source of cu rent having one pole grounded, transmitter and receiving devices in series circuit connection with said metallic line, a resistance in said line, and a switch device having one pole connecting with said resistance intermediate of its ends, and an opposite pole grounded for dividing said line into series circuit with the ground return and alternately for shunting said resistance.

4. In a signal system, comprising a metallic line, a source of current having one pole thereof connecting with the ends of said metallic line and the opposite pole thereof grounded and earth connection for said line for dividing said metallic line into independent circuits, each having an earth return, signaltransmitting apparatus for each independent circuit in circuit there'- with, receiving apparatus for eachindependent circuit in circuit therewith, and electromagnetic means having its magnet windings normally in circuit with said independent service lines for cutting out said earth connection and establishing a unitary metallic line. I

5. In a central station signal system, a pair of metallic circuit lines extending from the central station for a partial circuit, having a common earth return connection, a source of current having onepole thereof connecting with one end of said circuit lines,

and its opposite pole grounded, a resistance respectively for each of said service lines,

signal transmitting apparatus respectively ground return, a source of current having one terminal connecting with said metallic lines and its opposite terminal grounded, a plurality of signal receiving relays operated by different strengths of current, for each line, signal transmitting devices having a ground connection adapted when out in circuit with said line to shunt said resistance for changing the current strength for successively operating said relays, and a switch device for said metallic lines for connecting said lines to a ground return and alternately breaking said ground return and connecting said metallic lines.

In witness whereof, I hereunto subscribe my name, as attested by the two subscribing witnesses.

ALFRED E. MEYER.

Witnesses: I

CLARENCE B. Fosrn-R, MILDRED SMITH.

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