US1563652A - of rochester - Google Patents

Description

N. T. POWELL Dec. 1, 1925.

AUT OMATIC TELEPHONE SYSTEM FlGE HOLD

INVENTOR WIHFRED T. PQWELL.

SW TCH TALKING CCT.

ATTORNEY lt' atentecl UNITED STATES PATET E'Fltfllil.

'W'INFRED T. POWELL, OF ROCHESTER, NEW? YORK, ASSIGNOR TO THE STROMBERG- CARLSO N TELEPHONE MANUFACT UR-I A CORPORATION OF NEW YORK.

NG COMPANY, OF ROCHESTER, NEVT YORK,

AUTOMATIC TELEPHONE SYSTEMI.

Application filed January 18, 1922.

'1 0 all iii/1.0m. it may concern:

Be it known that I, l i lrrrnnn 'l. POWELL. a citizen of the United States. residing at tochestcr, in the county of Monroe and State of New York, have invented certain new and useful Improvements in Automatic Telephone Systems, of which the following is a full, clear concise, and exact description.

This invention relates to telephone systems and more particularly to telephone sy tems in. which automatic switches are employed in. completing some portion of telephone connections.

The purpose of the present invention is to provide a telephone system of relatively small capacity, the circuits of which are relatively inexpensive to install and are siin pie to maintain in operation.

The various features of the invention will appear from the detailed description and a ppcn (lflll claims.

In the drawings Fig. l diaera]mnatically represents the circuits and equipment necessary :tor three telephone lines. The equipment for each line is separated from that ot the other tclci hone lines by dotted lines and i it entities of the drawing. l ig'. 2 shows a detail ot the mechanical structure of the i omatic switch which is provided for each telephone line. Fig. 3 is a schematic showing ot' the talking circuit completed between two tclophmic lines.

lathis stcm each telephone line is proid'=- with an individual numerical switch thr ugh the terminals ot which. any other telephone line ot the system may he reached. The st ructure of this switch may he substantially similar to that disclosed in the patent to llullard zly'rlaltll'htlili patented .i'l-iugrust ii. cczept that the armatures and pawls the retaining magnet l and the stepping magnet o are not llltGl'lOCkll'lQ, but are oil. the arrangement substantially similar to that disclosed in Flog. 2 ot the present disclosure. lly rci'crencc to the patent to Bollard. it will be noted thatthc stepping nia ri'iot such as (3 advances the pair of switch wipers herein (it "7 and ti over their respective sets terminals. The stepping magnet 6 normally retains its stepping pawl out of engagement with. the ratchet wheel 2 of the Serial No. 530,115.

switch and the retaining or holding magnet l likewise normally holds its pawl out of engagement with the ratchet wheel. 2 and as will appear in the course of this description the operating pawls engage the ratchet wheel only during the time that its switch is in use.

The substation circuits of this system are of the type now well known in the art and are usually referred to as the local second.- ary type, since the receiver is in a circuit local to the substation and serially includes a secondary winding of an induction coihthe primary winding of which is in series with the central source of energy and also with the transmitter.

In this system an impulse sender is employed which may be of any well known structure and in which a set of in'ipulse springs is intermittently operated to cause a series of line interruptions commonly known in this art as impulses. The structure oi. this impulse sender. it the system is of relatively small size, (that is not over ten lines) or it the individual switch is three tively ope 'ated in response to several series of impulses, may he of the structure substantially similar to the impulse sender or dial such as is shown in the patent to Keith l:1,279. 352. issued September 17, 1918. If. however, the system is arranged for more than ten subscribers lines and it is still desired to directively set the subscribei."s individual switch in response to one adjust ment of the impulse sender then it will he desirable to employ an impulse sender ol? the type disclosed in the patent to Lattip; #LOElOAlQ, issued June 1912. The impulse sender previously ret'erred to is dia grammatically represent-ed lov a series of contact springs shown within the circle associated with each substation. circuit. The purpose o1 these various sets of springs will appear in the course of the present description.

The ringer or signal pr yided at each suhstatimi is commonly known in the art as a direct ctu'rentrinoger such as is normall employed in certain interconnnunicati ,5 telephone ."stems,or may he similar to the ordinary door hell ringer,

Yfith this-descriptlon the @Pl and certain of the circuits associatedtherewith, it is believed that the operation of the system will best be understood by describing the method of establishing a telephone connection from the subscrlbers substation designated A to a subscribers line the substation circuits of which are herein designated B. lVhen the subscriber at A removes his receiver from its switch hook, the contacts 10 are closed, thereby completing a circuit from ground, winding of the ringer magnet 11., through the t-ransi'mtter and primary winding of the induction coil, impulse springs 12 of the impulse sender, contacts 10, winding of the stepping magnet to grounded battery. Under the con trol of this circuit the stepping magnet advances its brushes 7 and 8 from their home position, to the next set of terminals herein referred to as a normal position of the switch. As soon as the stepping magnet 6 is energized itcloses an operating circuit for the slow releasing holding magnet 4 extending from grounded battery winding of this magnet, front contact and armature of magnet 6 to ground. The subscribers individual switch is now in condition to receive a directive series of impulses from the impulse sender. Since it has been as sumed that the connection is to be made to the line of the subscriber at B, it is necessary to transmit a series of two impulses from the impulse sender at substation A. This impulse sender is thereby adjusted to send two impulses and this adjustment, as is well lrnowi, results in the closure of the sets of contacts 13, 14 and 15 and subsequently in the intermittent closure of the set of impulse springs 12. The closure or the contacts 1% and 15 serves to short circuit the ringer magnet 11 and to connect ground to the impulse springs 12. This completes a substitute circuit for the step ping magnet 6 extending from grounded battery winding of this magnet, contact springs impulse springs 12 and springs 14- and to ground. When in the course of the operation 01 the imp'ulse sender it opens its springs 12, the stepping magnet 6 will retract its armature, but the holding magnet 4t will maintain the switch in the position to which it has been advanced. .skhnost immediately after the opening of the impulse springs 12, they will again be closed to complete the operating circuit of the stepping magnet 6 with the result that the brushes 7 and 8 are advanced from the so-callet normal position into position 1. In response to the next impulse from the impulse sender. the stepping magnet 6 will be deenergized as described but a circuit will soon after he completed by the closure of the impulse springs 12 so that the stepping magnet 6 will advance the brushes 7 and '8 into engagement with; the

#2 set of line terminals. The impulse sender has now completed the transmission of the series ofimpulses and its sets of contact springs 12, 13, 1%. and 15 will be in their normal condition, that is the condition in which they appear in Fig. 1.

It will be noted that as soon as the step ping magnet G deenergizes after the holding magnet l has been operated, an actuating circuit is closed for the cut-off relay 16, extending from grounded battery, lower winding of this relay, front contact and armature of magnet 4, back contact and armature of stepping magnet 6 to ground. The cut-oil relay 16 is energized in this circuit and is locked operated as long as the impulse sender springs 13 and 1% are closed. This locking circuit may be traced from ground, springs 13 and 1 1, conductor 17, lower armature and front contact of relay 16, armature and contact of magnet 4, lower winding of cut-oi? relay '16 to grounded battery. At the close of the series of impulses, the sender springs 13 and 1e are opened to permit the release of relay 16. 5

The previously described operation of the automatic switch individual to the calling line has advanced the brushes 7 and 8' into engagement with the terminals 18 and 15) of the wanted subscribefis line. It ,will first be assumed that this line is idle so that when the subscriber at A signals the subscriber at B by depressing the ringing button 20, a ringing circuit is closed from grounded battery, winding of the stepping magnet 6, switch hook springs 10, ringing button 20, conductor 17, lower armature and bacl: contact of cut-oil relay 16 switch brush 8, which is now in engagement with the multiple terminal 1-), conductor 21, brush 22 of the wanted subscribers switch, lowermost contact and armature of the outofi" relay ..3, conductors and back contact, armature and winding of the ringer magnet 26 to ground. It will thus be seen that a self-interrupting circuit is closed for the ringer magnet 26, which causes it to vibrate its armature and actuate the bell at the wanted subscribers station. At this time condenser 3% serves to quench the spark at the contacts of ringer magnet 26. The alternating current generated by the operation of the ringer magnet 26 causes a tone to be heard in the receiver at the substation at A so that the subscriber thereat can tell that the wanted subscriber is be ing signaled. When the wanted subscriber at B answers by removing his receiver from its switch hook the ringing of lllS bell is immediately stopped since the ringer magimpulse springs 2?, switch hook springs 28,

winding of the stepping magnet 29 to grounded battery. The stepping magnet 29 is also energized in this circuit and ad- 'Vt nc the brushes 30 and 22 ot the wanted subscl'ribcr s switch to the so called normal position that is in engagement with the terminals 31 and 32. The subscribers s Witch is therefore advanced from its home position so that his telephone line cannot be seized by some other subscribei."s switch.

The telephone connection is now complete between the substations at A and B and the talking battery tor the ailing; subscriber supplied over a circuit from grounded battery through the winding; of the stepping magnet 6, switch hooh springs 10, inn iulse springs 12, primary winding of the iudu tion coil" through the transn'iitter, winding of the ringer magnet 11 to ground. 'lalhing' battery for the called subscriber is supplied from grounded battery winding of the stepping;- magnet 29, switch hook springs 28. impulse springs 27, primary winding of the int .ction coil; through the called subscribers transnntter and w nding' ot the ringer magnet 26 to ground. lit will be noted that ringer magnets 11 and 26 are ope'ated at this time to remove the short circuit from condenser; 33 and 3 1. It will thus be seen that the ringer magnets 11 and 26 also t inction as impedance coils for the talking; circuit. It will further be understood that the condensers such as 323 and 31!; serve to inductively connect and conductively separate the conre 'sational circuit exteiuling between the cal iu and wanted iuiliscrihei l it now be a i tt-riniuatingr at s1 tation i3 uh idy engaged inconi'erszt u and that this line busy as a called line. its set ()1 hrushei-i 9 I 1 nd 30 will. there tore be in en asement with described the terminals 31 and a as nice: or

s: that the ringing: circuit preiiouslv dei-zcrihed as including coinluctors 724i: and will not be conugleted and conseipuintty no ri t ring tone will be heard in the calling sub l scriheifs receiver. The :taiiure to hear {iii-5 tone after the extension ot the co:inection is a si nal to the calling; party that the wantcc li..e is busy. This is in the nature ot a negative signal but one which is etiective when the SlJ JSQlllJtEi'S are ins ructed as to the opcrmtion oi. the 'steni.

lit nil be ,a. dd that the cut-oil lt calling line locl zed en.

stinent ot the caliin cit-ch in 1 it the called line is bus}; due in fl --t w act Liar In nasiictli prev ens sci/lo her line. such as that terminating at ion te this i. tag-r will be loclted operthe call i h subscriber disconnects. e circuit for this relay now extends from ground armature and troutcontact of may iiet upper winding: uo er trout contact and miniature of relay it), switch brush i,

terminal 18, multiple terminal 35, brush 56 ot the subscribefls line terminating at G, upper armature and back contact or cut-oil relay 37, winding of the stepping magnet 38 associated with the C subscribers individual switch, to grounded battery. Under the con trol of this circuit the cut-ed relay 16 is locked operated and prevents the completion of the ringing circuit over conductor 1.? and this insures that the connection now established between substations and Q will not be disturbed.

It the line terminating at B substation is busy due to the fact that this line has originated. a call, the brushes 22 and 30 of its associated so itch will be ad anced beyoi their so called home and normal posi tions so that the ringing circuit tor the substation A willv not be completed with the result that the it subscriber can hear no ringing tone and will know that the wanted line -annot be reached.

At the close of the conversation the *alling subscriber at A restores his portion of the established connection by simply replacing his receiver on its switch hook thereby opening the switch hook springs with the suit that the steppiin; magnet 6 deci'iorgnzes and shortly utter tne slow releasing n agnet -xl deenergrizes. This permits the 'eiract re spring of its associated switch to restore the brusliies "Z and 8 ct this switch to their home on. Similarly when the called .ulr at sub-station l3- rcplaccs his revolver on its switch hook, springs are opened to permit the z-steppinp; magnet to decncrggizc and shortly atterwards the slow releasing holding magnet -10 of this switch decne so that the retractive spring of the 1...:T subscriber's switch. restores the brushes 2:2 and oi this switch to their normal positiou.

ll hile the subscribefis individual switches have not been (itfii'liiitti in deia'l operating); on the cumulative ncipl it is to be understood that these switches i ray be so opcrated without any chance in t 1e operating circuits. .iiutoinatic switches operated on cumulative priuci iilc are also reterrcd to adding type switches and un be described as advanc' uai to the in; um

I a number ()5, steps cu :uun oi. the im iiulses in sereral series of imf JttlSLS, instead of being} advanced in the well known group and line. selcctin increments.

it will thus be seen that a. simple ttlit0- inatic telephone system is provided in which a ininnnuin amount of equipment is used and in which relatively simple (operative circuits a re employed.

automatic telephone system. a irality of telephone lines. a subst; tion for telephone line. a. telephone transmitter. .4. e iihone receiver and a ringer magnet at. each i-iubstatimi, a pin 'ality oi automatic switches, each automatic switch having passive contacts and active contacts ar 'anged to be progressively advanced over said passive contacts. a motor magnet for advancing the active contacts oi each switch, each telephone line terminating in the active contacts oi one automatic switch, certain of the passive contacts ot said automatic switches being multipled together, means associated with the calling substation for directively controlling the operation of its assiciated automatic switch for extending said calling tclephcme line to a vanted telephone line, a common source of current, and means including circuits having therein the impedance oi the motor n agnets and ringers associated with the calling and talled telc phone lines tor connecting said source of cur rent to the telephone transn'iitters of these lines.

2. In an automatic telephone system, a plurality of telephone lines, a substation for each telephone line, a telephone transmitter, a telephone receiver, a ringer magnet and a ringing key at each substation, a plurality of automatic switches, each automatic switch having passive contacts and active contacts arranged to be progressively advanced over said passive contacts, electromagnetic means it advancing the active. contacts of each switch, each telephone line terminating in the active contacts of one automatic switch certain of the passive contacts 01 the said auton'iatic switches being multiply connected tog ctlwr means associated vith the calling suhstation tor controlling the operation oi the el etromagnetic means of its automatic switco tor extending said calling substation to a wanted substatiom a ringing circuit including: the rin r magnet at the suhstation, means including the ringing L at the calling substation, tor controlling said circuit. a common source of current, and n'ieans including a circuit having; therein the impedance of said electromagnetic means and the ringer magnets associated with the calling and called telephone lines tor cminectin r said source ot current to said transmitters.

in an automatic telephone system, a plurality oi telephone lines, a substation tor each telephone line each substation havinc a telephone receiver, a telephone trammitter and a ringer magnet, a plurality 0t automatic switches each automatic switch having passive contacts and active contacts arrang' d to be progressively advanced over said pasive contacts electromagnetic means for advancing; the active CODt-tCtTS of each switch, each elephone line terminating: in the active contacts of one auton atic switch, cer am of said passive contacts being multiply comected together. means associated with a calling substation directively control lins the operation of the electromagnetic means of its associated switch for extending said callii substation to a wanted substation a conin'ion source of current, means including Zrcuits having therein the impedance of the electromagnetic means and the ringer magnets associated with the calling and called telephone lines for connecting said source of current to their transmitters and means including a condenser at each substation ot a completed connection for c inductively separating said transn'iitter circuits from each other.

4. In an automatic telephone system a arality ot telephone lines, ea h telephone 1c being); provided with a transmitter and a receiveri means including an automatic switch individual to a telephone line tor ex- LtlltllllQ said telephone line to any ot the other telephone lines. a conunon source ot current; means iucliulin; portions of the calli and called telephone lines for supplying current to the transmitters associated with said telephone lines, and means including condensms located at the calling and called substations tor inductively connecting hut conductivcly separatiim' the telephone "ransers of an established connection 5.111 an automatic telephone system. a plurality of telephone lines a substation associated with each telephone line, each substation being provided with a telephone receiver, a telephone transmitter and a call signal, an automatic switch individual to each telephone line for extending said telephone line to any of the other telephone lines electromagnetic means arranged to he directively controlled from a calling substation for directively operating the automatic switch of a calling telephone line to extend said line to any i 'anted telephone line, means including a circuit extending over said calling and called telephone lines through said automatic switch tor establishing a telephonic connection between the telephone receivers and transn'iitters at the calling and alled substations, and a second circuit including a portion of said first circuit for actuating the call signal at the wanted substation, said circuit serially including the electromagnetic means of said last mentioned switch.

6.111 an automatic telephone system a plurality of telephone lines a substation. for each telephone line having a telephone re ceiver a telephone transmitter and a call signal an automatic switch individual to each telephone line for extending said telephone line to any of the other telephone lines, electromagnetic means associated with said switch, said electromagnetic means being directively controlled over a calling telephone line, a common source of current, 11 cans including said source of current for actuating the call signal at the wanted substation, means operated simultaneously with said ltltl llt) llS

messes walled signal for causing a tone in the ceivcf at the calling substation, and nicer-s for connecting uaid source of current to t telephone tr: iin'iitters oi the cstablisl ed connection.

7. In an automatic telephone system, a plurality of telephone lines, a substation having a transmitter for each telephone line, an automatic switch indi idual to each telcphone line for extending said. telephone line to any ot the other lines, incai'is t'or dircr tivcly ope'atingi; each automatic switch, a common source ot curreit, and circuits for connecting said source ot current to the transnnitters ot a completed telephone connection, said circuits each including a current teed coil and a winding of an iiuluction coil at each of the substations of the telephone connection.

8. In an automatic telephone system, a pluralit of telephone lines, a substation for each telephone line having a telephone transmitter, a telephone receiver and a call signal, a n automatic switch for each telephone line" means for directively operating each automatic s'vitch :lor cnniecting said tcle phone line to any other telephone line a con'n'non source of current or said tcle honc transmitters and call signals, means uicluding a portion ot the calling and called telephone lines for causing said source o l? cuu rent to actuate the called signal and interrupt its own circuit at the wanted sulr-ztation, a telephone circuit interconnecting the calland called telephone line, said circuit including the transmitters of said telephone lines, a condense f at each oi"- the substations of the associated connections for conduc tively dividing said telephone circuit into two parts, one part including each. trznsinitter, means for bridging said source of current to each transmitter, and means in cluding the mentioned condenser associated with the called siiibstatiim tor quenching the sport; at the iutern'iittmitlr opts-a ling culled. s i gn a] 9.111 an automatic telephone system, a plurality of telephone lines, a telephone transmitter, a telephone receiver and a call. signal for each telephone line, an auton'iatic switch individual to each telephone line tor connecting said telephone line with any t (Y the other telephone lines, directively con trolled means for operating each individual switch for causing it to seize any wanted telephone line, a call signal a each substation, electromagnetic means including a e tinterrupting circuit for actuati.,..; the ll signal at a wanted substation, manual means at the calling substation for controlling said circuit, a condenser at each substation nor mally bridged about the contacts of said electromagnetic means, and means tor continuously energizing the electromagnetin'icans at the calling and called sub tations during the n'iaintenau -e of a telephone (Ullnection.

it). in an autmnatic telephone plurality oi" telephone lines, a each telephone line, a telephone trausui a receiver and a ringer inagi'ictin each ittcr, sul station, a plurality ot autinnatic switches for interconnecting said telephone lines, a

or l'lllt"tt for advancing each automatic s us inchidiug one of said switches and its motor magnet for extending one of said telephone lines when calling to a fluted telephone line, a coalition source 01 v: 'urrent, and n'ieans including a circuit having therein the impedance of said last mentioned niotor magnet and the ringer magnet of the ailing telephone line for connecting said. source of current to the telephone trans niit-ter of aid calling telephone line.

it. in an automatic telephone s: tent, a plurz lit-y oi telephone lines, each telephone line being provided with a transmitter and a receiver, means including an automatic switch for extending a calling telephone line to any oi? the other telephone lines, a common source of current, means including portions of the calling and called telephone lines for supplying current to the transmittic assi'iciatcd with said telephone lines, and is including condensers located at the called and calling substations :t'or inductivel connecting and conductively .eparating t re telephone tr: nsinitters of an established telephone connection.

123. In an automatic telephone system, a plurai'ty of telephone lines, a suhstation tor each telephone line having a telephone receiver, a telephone transmitter and a call signal, an automatic switch for extending a telephone line when calling to any of the other telephone lines, elect-r magnetic means associated with said switch, said electromagnetic means being direct-i'vcty controlled by a ailing telephone line, a source of current, ringing lllQttt'lS including; said source ot cur-- renttor actuating said all. signal at the wanted. substation, means ope 'ated simultaneouslx with said called sipnial for causing a tone in the receiver at the calling substalion, and means including a portion of said ringing means for connecting said source of current to the telephone transmitters 01" the established connection.

13. ltn an automatic telephone system, a plurality of telephone lines, a telephone transmitter, a telephone receiver, and a call signal for each telephone line, means in cluding an automatic switch for connecting a telephone line when calling to any other telephone line, directivcly controlled means for operating saio automatic switch for causinn it to seize a wanted telephone line, electromagmatic ineai'is including a selt-interruptinn circuit tor actuating the cell signal at a ranted sulrstation, manual. means at the calling substation for controlling said circuit, condensers at each substation normally bridged about the contacts of said electromagnetic means, and means including a portion of said self-inten'upted circuittor continuously energizing the electromagnetic means at the calling and called substation during the maintenance of the telephone connection.

In witness whereof, I hereunto subscribe 10 my name this 17th day of Januany A. D. 1922.

XVINFRED T. POXVELL.

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