US1209825A - Telephone system. - Google Patents

Description

J. ERICKSON.

TELEPHONE SYSTEM. APPLICATION FILED DE C.18,I908- RENEWED MAY 29.1916.

Patented Dec. 26, 1916.

J. ERICKSON.

TELEJ'PHONE SYSTEM. APPLICATION FILED DEC,"18,l908. RENEWED MAY'29. 1916.

1209,25. Patented Dec. 26,1916.

5 SHEETS-SHEET 2.

mam /:39; 2 77mm J. ERICKSON.

TELEPHONE SYSTEM.

APPUCATION FILED DEC.18,1908- RENEWED MAY 29.1916.

1 209,825. Patented Dec. 26, 1916.

5 SHEETSSHEET 3- J? a. 7%ZZ.

J. ERICKSUN.

TELEPHONE SYSTEM. APPLICATION FILED DEC. 18, 1908- RENEWED MAY 29.1915.

1,209,25. Patented Dec. 26,1916.

5 SHEETSSHEET 4.

Jx ERICKSON.

TELEPHONE SYSTEM. APPLICATION FILED DEC. 1a, 1908. RENEWED MAY 29.19l6.

1 9,825 Patented Dec. 26, 1916.

5 SHEETSSHEET 5.

%TATE% @FFICE.

JOHN ERICKSON, OF CHICAGO, ILLINOIS, ASSIGNOR TO AUTOMATIC ELECTRIC COMPANY. OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

TELEPHONE SYSTEM.

Specification of Letters Patent.

Application filed December 18, 1908, Serial No. 468,141. Renewed May 29, 1916. Serial No. 100,702.

To all whom 2'25 may concern Be it known that I, John EmoksoN, a citizen of the United States of America, and resident of Chicago, Cook county, Illinois, have invented a certain new and useful Improvement in Telephone Systems, of which the following is a specification.

My invention relates to automatic or semiautomatic telephone exchange systems in general. but more particularly to those in which the substations are provided with rotary calling dials, and especially to systems in which the said dials are used for controlling the operations of switches that have one motion to select groups and another motion to connect with a line in any selected group, as, for example, selectors that have one motion to select groups or divisions of the exchange and another motion to automatically select an idle trunk line in the group or division selected by the calling subscriber. or a connector that operates in the same manner, except that its second motion is under the control of the calling subscriber to seize or find the called line.

An object of my 'inzvention, broadly speaking, is to provide an improved arrangement whereby the dial cannot be forced or so manipulated as to accelerate the impulse-transmitting mechanism, and which will make the proper transmission of the impulses a matter of greater certainty, especially in cases where the subscribers are inclined to be careless about the way in which they use the calling dials.

More specifically considered, an object of my invention is to provide a calling dial which can only rotate in one direction, and which is operatively connected with the impulse-transmitting mechanism. whereby the dial cannot be forcibly turned backward to unduly accelerate the transmission of electrical impulses.

Another object is to provide a measuredservice system of such character that the calling subscriber is required, by means of improved mechanism, to remove a short-circuit or shunt from around his transmitter, and to thereby register thecall. before he can converse with the called subscriber.

' To these and other useful ends my invention consists in matters hereinafter set forth and claimed.

In the accompanying drawings Figure 1 is a front elevation of the keyboard, show ing the rotary dial. Fig. 2 is a rear elevation of the keyboard. Fig. 3 is a side View thereof as seen from the right in Fig. 1 Fig. 1 is a cross-section on line 4'4 in Fig. 2. Figs. 5, 6, 7, 8, 9, 10, 11, 13,14, 15 and 16 are detail views of the keyboard mechanism. Fig. 12 shows a switch-hook spring combination. I 17 is a diagram of the substation A comprising a keyboard of the character shown in the preceding figures. Said substation is connected with automatic switching apparatus in a central oifice, Said apparatus being of the character designed to be operated by the said keyboard, the said switching apparatus, as shown, comprising a line switch C, a controlling master switch D and a first-selector E, and there being a central battery B for supplying all operating and talking current.

My improved calling device comprises a dial guard Z upon which there are placed numbers for aiding the subscribers in selecting the proper finger-hole in the dial 2. The calling device also comprises the usual governor gear wheel 4, and switch-hook 5 which controls the switch-hook springs (Fig. 12) by means of the cam arm 6 2).

In Fig. 4 is shown how the rotatable parts are mounted upon the shaft 7. The dial 2 is secured to the hub S, but the hub in turn is loosely mounted upon the shaft 7, so that the dial may be turned without rotating the shaft. One end of a coil spring9 engages a slot 10 in the hub 8 (Fig. 8). The other end of this spring is secured to the spring box 11, to which latter is also fastened the impulse wheel ratchet 12. The members 11 and 12 are firmly secured to the shaft 7, and

hence when the ratchet wheel 11 is turned the shaft and all the parts secured thereto are rotated. Also fastened to the dial on the inner side is the dial ratchet wheel 13. The gear wheel 4, together with the impulsetransmitting wheel 14, are secured to the hub 15. and the hub 15 in turn is rigidly fastened to the shaft 7 by a screw clamp 16. The shaft 7 carrying all the parts secured thereto. is adapted to rotate in bearings in the front and back plates 17 and 18. The pawl 19, which controls the ratchet wheel 13 (Fig. 9) is pivotally secured to the link 20 at the point 21, and the link 20, which is provided with the arm 22, is pivotally mounted on the front plate 17 at the point The special spring 24 provides the teneion For the parl and arm wr :35, which piviited t the poo All. arranged to n5 l. the ratchet .30. hi normal rel: and ratchet 510 there are silo on th e p: i ions "uni-c when the ratchet wlicei l3 1.-

tlnfned in the direction indicated by the armor. Since there is spring-coiinection between the dial and ratchet wheel with the wheel 12, there is a tendency for this latter wheel to follow in the direction oi the dial, but this is not permitted by the lever atthis time. In Fig. 11 tl'icrc are shown the relative positions these parts as-nuue when the dial is relea When the dial is released the wheel 13, which is rigid with the dial, due to the tension placed on the spring 9 (Fig. 4), tends to rotate in a direction opposite "to that indicated in Fig. 10. A tooth 27, however, innnediatcly engages the pawl 19 and carrios the latter hack a trifle, thereby moving the pawl l!) and link against the tension of the spring 2 about the point 23. W hen this occurs the arm 22 presses against the outside lip of, the lever 25, therebj carrying the latter out of engagement with the ratchet wheel 12. The wheel 12 and shaft 7 then respond to the tension in the coil spring 9 i) and more in. the direction indicated by the arrow in Flf; ll. The ilial. ratchet wheel 13 remains locked at this time. lfpon the other end of the shaft 7 (as shown in Fig. 4) is mounted the impulse Wheel ll. and gm:- i'vhecl l, as explained. The impulse wheel 'l-l. in turning; counter-clocliwise (Figs. 1:3 and lo}, presses against the spring 98. thus separating the impulse springs and each time a tooth passes the SPl'l'l When the dial is turned. explai. tho stop screw 1 upon he wh i carried a way from the incu'zbm' 3Q, when. the dial is released the shaft '7' and. all. the parts secured thereto follow or rotate in the same direction as the dial until the member 3'2- reaches the stop screw 31 (Fig. 7). The distance or arc that the stop screw ad- Yancos from the member accurately and definitely determined by the finger-holes in the dial. ll licroifiu'c, when the dial is turned for the digit the stop screw 31 is advanced through an arc such. that the member 32, in coming to normal position. again, permits the impulse wheel 14: (Fig. 15) to break the normal contact between the springs 29 and 30 live tin'ics. The gear wheel l engages the pinion of the governor 3, which latter controls the rapidity with which impulses are transmitted. V

In Figs. 13 and. 14- it will be seen that there are two notches or positions in the lever 33 for the end of the switch-hook 5. This prosubscribers vision is made in order that certain tclc phone circuits may be controlled throu h the switch-hook springs. llhcn the receiver is removed from the switch-hook the end of the latter occiu'iies the position shown in Fig. lb, and when the dial comes to rest after a digit has been called the switchhooh rests in the position shown in Fig. 14-. This operation is bri'iught aoout as follows: When the receiver is removed the end the switch-hook rests in the notch 'l-l. Normally. however. before the eeccircr is removed, the switch-hoolcres'is against the stop After the dial is turned and then comes to rest," the pawl mechanism, as explained. presses the lever 25 out of engagenient with the ratchet wheel 1. Also, when this happens the finger 36 upon the lover presses the lever 33 outwardly a trifle (Figs. 11, 13 and 14). thereby permitting the switch-hook 5 to fall to the notch 3?.

In the foregoing the mechanical construction and arrangement of the different parts of my calling device have been explained. It will now be pointed out how the calling device may be used in connection with a telephone for operating the switches of an automatic central. ollice. shown in Fig. 17, the substation Av coinprises, in addition to the calling device, the receiver 38, ringer 39 in series with the con denser 40, an induction coil 41 comprising the primary winding and secondary winding 43, and a transi'nitter 44.

In Figs. 12 and 17 the switch-hiioli spring combination is arranged for the operation of meter or registering device at the telephone. If the meter or registering device is not used, then the two lower 'lllflS 5% and are not used. and the switch-hook spring; combination is the same as shown in Figs. l. 9 and 3. In addition there is shown a meter or registering mechanism. cons'slw inn o? the paslrbutton l?) which when. pressed, discngagrs the springs 46 and *i? and also moves the ratchet wheel 48 of the motor 4.9 one step; Furthermore, when the button is thus operated the pawl 50 falls over the end of the spring 47 and locks the latter in its operated position until the receircr is restored to the switch-hook, thereby unlocking'the push-button spring when the rod 51 engages the pawl 50. The line conductors 52 and 5301 the substation A terminate in the line switch C, which is of the general type of line switch disclosed in English Patent No. 26,30l of 1906, and in the W est/11m Electrician published at Chicago, Illinois, U. S. A, January 25, 1908. The controlling master switch D is also disclosed in the above references. The selector switch E is of the general type of selector switch. shown in United States Letters Patent No. 815,321. issued to Keith, Erickson and Erickson March 13, 1906. As shown in Fig. 17, all of the switches and the telephone A are wired with circuits such that they will operate on a two-wire s \'stemthat is, there is no operating ground at the subscribeus station, the impulses being made by opening and closing the two line conductors in series, so that the ground connections are employed at the central otiice only. \Vhen the subscriber removes the receiver 88 from the switch-hook 5 the springs 51 and 55 engage and the springs 50 and 57 disengage. The spring 57, however, does notcngagc the spring 58 until the dial is turned, when the switch-hook 5 engages the lower notch 37 (Fig. 14) as explained. The engagement of the springs 51 and 55 closes an energizing circuit tin-ough the trip magnet 59 ot' the line switch C. This circuit extends from ground G at the line switch through the trip magnet 59, bridge-cut-ott' springs 60 and 01 to the line conductor 53, through the primary winding 42, transmitter H, springs 55 and 54, impulse springs 29 and 30 to the conductor 52, bridge-cut-ott springs 62 and 63, resistance coil 641 to the battery lead 05, thence through battery B to ground G. The trip magnet 59, upon energizing, attracts its armature and permits the plunger to engage an idle bank terminal, thereby pressing the springs 66 and 67, 68 and GE) 70 and 71, and 79 and 73 into contact. The engagement of the springs 70 and 71 estab lishes and energizing circuit through the bridge-cut-otl' relay 7 1 which operates to disconnect the line conductors 52 and 53 from the line switch connections. Also, when the springs 7 0 and 71 engage, then a positive guarding potential. is established over the conductor 75 at the connector private bank contact corresponding to the line of substation A. The engagement ofthe bank springs 68 and 69 closes a. energizing circuit through the motor magnet relay 76 of the master switch D. This circuit extends from ground G through the winding 77 to the common segment 78 of the master switch bank wiper 79, to the individual contact SO (assuming that this contact corresponds to the bank terminal just engaged by the line switch C), conductor 90, bank springs 69 and 68, winding of the release magnet 91 to the battery lead 65, thence through battery B to ground G. Although this circuit includes the windings of the release magnet, the said magnet does not. operatively energize, since the winding 77 of the relay 76 is of such comparatively high resistance that a very small current is flowing. The relay 76, upon energizing, presses the springs 92 and 93 into contact, thereby closing an energizing circuit through the motor magnet '94 extending from ground G through the springs 92 and 93, interrupter spring 95, motor magnet 94 to the battery lead 65, thence through battery B to ground (1. The motor magnet energizes and operates the ratchet wheel 00 one step, assuming the next trnnh'.line is idle, whereby the shall 07 carries the idle plungers opposite the next idle bank terminal and the wiper 70 into engagement with the imlividual contact corresponding to the idle trunk. The cngagcment ol' the bank springs 06 and 0? and T2 and '73 extends the substation line conductors 52 and 53 to the trunk line conductors 0S and 90, respectively, which lead to the selector switch 10. An energizing circuit is immediately closed through the line relay 100 extending from ground G through the winding 101, side switch wiper 102, conductors 00 and 53, through the substation to the conductors 52 and 98, side switch wiper 103, winding 101. to the battery lead 05, thence through battery B to ground G. This line relay energizes and separates the spring 105 from the spring 106, and closes the springs 105 and 107 in contact. The engagement of the latter springs closes an energizing circuit through the slow-acting release relay 108 which operates to in turn carry the spring 109 out of engagement with the spring 110 and into engagement with the spring 111. The line relay 100 remains in this energized position as long as the line at the substation is closed, but when the dial is rotated, and in turn the impulse. wheel 11, the impulse springs 29 and. 30 are then separated momentarily, thereby intermittently breaking the energizing circuit of the line relay 100. The deenergizing of the line relay 100 permits the spring 105 to engage the spring 100, thus closing a circuitthrough thew'crtical magnet 112. This circuit extends from ground G through the springs 105 and 106, springs 109 and 111, private magnet relay 113, vertical magnet 112, side switch wiper 114 to the battery lead 65, thence through battery 13 to ground G. The vertical magnet energizes and operates to carry the shaft wipers 115, 116 and 117 in a vertical direction one step at a time for each impulse. Since the vertical magnet circuit includes the private magnet relay 113, it also ener-- gizes and places the springs 11S and 119 in contact, thereby closing a circuit through the private magnet 120 from ground G The private magnet relay 118 energizes {upon the first vertical impulse to the vertical magnet and, being slow-acting, remains in this energized position until all of the vertical impulses are set, and then, since the energizing circuit is no longer maintained, the relay 113 restores to normal position, breaking the energizing circuit for the private magnet 120 which operates to pass the side switch to second position. The side switch wiper 114, upon passing to second position, closes an energizing circuit through the retary magnet 121 which operates in the usual I relay 128 of the switch F in the same man-- 125. When the side switch wipers 103 and 102 pass to third position the line conductors 52 and 53 are extended to the shaft wipers 115 and 116, respectively, and to tl e trunk conductors 126 and 127, thereby closing an energizing circuit through the line nor in which the circuit was closed through the line relay 100 of the switch E. The calling subscriber may operate the line relay 128 of the switch F in accordance with the next digit of the desired number. After having operated the dial for each digit and established connection with the desired line, the two subscribers may carry on communication. The subscriber at substation A, however, before he can successfully talk with the called party, must press the button 45, thereby separating the springs 46 and 47 and operating the meter one step, as explained. It will be seen that before the meter button is pressed there is a shunt around the transmitter 44 through the springs 58 and 57 to the spring 54. The calling subscriber, moreover, may hear the called party answer, but before the calling subscriber can reply, the transmitter shunt must be removed by pressing the button which registers the call. The meter mechanism, when once operated, re mains in its operated. position until the calling subscriber restores his receiver to the switch-hook and thereby unlocks the locking pawl 50. The restoration of the central office switching apparatus occurs when the calling subscriber restores his receiver to the switchhook and opens the energizing circuit for the line relay of the connector switch. The line relay, upon deiinergizing, breaks the energizing circuit for the slow-acting release relay, which in turn also falls back, thereby removing the ground potential from the private bank contact engaged by the private wiper 117. The removal of this ground also breaks the energizing circuit of the slowacting relay 108 of the selector E. This relay then falls back, placing the spring 109 in contact with the spring 110, thereby cl0sing an energizing circuit through the release magnet 125 extending from ground G through the springs 105 and 106, springs 109 and 110, through the release magnet 125, normal springs 124 and 123 to the battery lead 65, thence through battery B "to ground Gr. The release magnet, upon energizing, restores the switch shaft and side switch to normal position. i/Vhen the switch shaft roaches normal position the normal armlQPi upon. the shaft carries the normal springs 123 and 124 out of engagement, thereby tweaking the energizing circuit for the re magnet. The release magnet, when enzed, holds the springs 129 and 180 in contact, thus closingthe energizing circuit for the release magnet 91 of the line switch C. The release magnet 91 energizes and opcrates the release mechanism to withdraw the plunger from the bank terminal and permit the bank springs to restore. to normal position. At the subscribers station, when the receiver is restored, the switch hook springs return to normal position; also, the rod 51 presses the pawl 50 so that the meter button springs return to normal position.

From the foregoing it will. be seen that there is no normal position for the dial and the impulse wheelthat is, the dial is r0- tated in one direction only, also the impulse wheel. Whenthe dial is turned for any number, tension is placed in the dial coil spring. This tension is transmitted to the shaft, but the shaft is preventedfrom turning until the dial comes to rest. when a lever which holds the shaft locked is removed. The shaft being free then responds to the spring tension and rotates'in the same direc tion that the dial was previously turned. The number of impulses transmitted is determined by the are through which the dial is turned-that is, the impulse wheel, in response to the spring tension of the dial springs, rotates through an equal are. It will be seen. that the switch-hook 5 is permitted to pass from tne position shown in Fig. 13 to the position shown in Fig. 14 by the action of the lever 25. This iever 25, by being pressed away from the gear 12, as shown in Fig. 11, through the medium of the pin 36, presses the catch away from the switchhook 5, thus permitting the said switch-hook to pass from one position to the other.

In the foregoing reference has been made to connector switches. It should, therefore, be stated that connector switches with which the selector E is adapted to establish connection for completing the circuit between the calling and called subscribers are of'the general type disclosed in United States Letters Patent No. 815,176, issued Viarch 13, 1906, to Keith, Erickson and Erickson. More particularly, however, the connector switches in this system are adapted to the particular character of system and. circuits herein disclosed.

It wili be seen that I provide a rotary impulse wheel and a rotary calling dial operatively connected together in such manner that the dial rotates first and the impulse wheel afterward, the rotation of the wheel always being coextensive with and determined by the rotation of the dial. The dial is rotated for the different digits of the called number, and at the end of each rotation the impulse wheel is released and allowed to catch up with. the dial-that is to say, the wheel and the dial are always normally in the same relation to each other, notwithstanding that the dial is rotatable while the wheel is standing still. The dial and the wheel rotate successively, one after the other, and the rotation of the wheel always corresponds in degree to the rotation of the dial. The dial rotates ahead, drawing away from the wheel, so to speak, but as soon as it stops the wheel is then released and allowed to catch up and regain its normal position relative to the dial. Thus the dial and the wheel rotate always in the same direction, the dial rotating first and the wheel afterward, the release of the wheel being effected by a very slight back rotation of the dial. Obviously, however, the dial is never rotated backward to an extent to bring it to its normal position. In view of its continuous rotation always in the same direction the dial is, therefore, provided with an endless series of finger-holes adapted to be used in the manner described. It will also be seen that the calling subscriber, after establishing connection through the automatic apparatus to the called line, cannot then converse with the called subscriber until after he has removed a short-circuit or shunt from around his transmitter. When the calling subscriber does this he at the same time registers the call, or collects the coin or check. For the broader purposes of my invention the measured-service device may be of any suitable character that is to say, it may be a coin or check controlled mechanism or a call-registering device of any suitable, known or approved character. Whatever it may be, however, the use of the calling subscribers transmitter to converse with the called subscriber is contingent upon the operation of such device.

What I claim as my invention is:

1. In a calling device, an electrical impulse-transmitting mechanism, a rotatable dial connected for operating said mechanism, means for permitting the dial tonotate backward only a portion of its forward rotation, and means governed by the said limited backward rotation of the dial for causing the said mechanism to transmit the impulses.

2. In a calling device, an electrical im pulse-transmitting mechanism,'a dial rotatable to cause the operation of said mechanism, and means for preventing said dial from returning to normal position, the latter having an impulse wheel rotatable only in one direction.

3. In a calling device,-a rotary impulse wheel, a calling dial connected for operating said wheel to transmit a plurality of series of impulses, means for preventing said dial from returning to normal position during said operation, means operative to cause the wheel to rotate in the same direction as the dial. after the latter has reached the, limit of its rotation, and means for limiting the rotation of the wheel to the distance traveled by the dial, whereby the dial rotates first and the wheel u'l'terwurd in the same direction.

l. In a calling device, a rotary impulse, wheel rotatable in but on direction, a calling dial ha ringno normal position, a spring arrangcd to be. placed under tension by the. forwardrotation ol the dial, and means for then permitting said spring to rotate the wheel in the same. forward direction when the dialis released.

5. In a. calling device, a manually-operated dial and an impulse wheel rotatable only in one direction, a spring for rotating the wheel a distance each time equal to the forward rotation of the dial, means for holding said wheel against rotation, and means for autonmtically releasing the wheel when the dial is released, whereby the dial and wheel always rotate successively and in the same direction.

6. In a calling device, an electrical impulse-transmitting mechanism rotatable in but one direction, a dial connected for operating said mechanism, and means for preventing said dial from rotatively returning to normal position when rotated forward to operate the said mechanism.

7. In a calling device, an electrical impulse-transmitting mechanism rotatable in but one direction, a rotatable dial connected for operating said mechanism, means for permitting the dial to rotate backward only a portion of its forward rotation, and means governed by the said limited backward rotation of the dial for causing the said mechanism to transmit the impulses.

8. In a calling device, an electrical impulse-transmitting mechanism, a dial rotatable to cause the operation of said mechanism, and means for preventing said dial from returning to normal position, the latter having an impulse wheel rotatable only in one direction, said dial including an endless ,series of finger holes.

91 In a calling device, an electrical impulse-transmitting mechanism comprising an impulse wheel, a dial connected for operating said Wheel, said wheel rotatable in but one direction, means whereby a plurality of successive operations of said dial will operate said impulse wheel to transmit a plurality of series of impulses, and means for preventing said dial from returning to normal position during said operation.

10. In a calling device, a dial, an impulse Wheel, a spring for rotating the wheel a distance each time upon the forward rotaulse wheel zwainst rotation and means h 3 CODlZl'OllQCl by the clial for releasing said wheel, whereby the dial and wheel rotate successively.

11. in a calling de -doe a dial, an im- Jig the wheel with the said pulse wheel a spring for rotnr J {L variable distance in accordance rotation oi the dial, Trv ans for loi .1 impulse wheel against 2. tution, anvil controlled by the dial for releneing Szi'lC; wheel, whereby the dial and. wheel rotate successively.

12, In it calling device, an impulse transmitter comprising a tllill and mi impulse wheel, the dial having no normal position, a spring for rotating the impulse Wheel a distance in accordance with the variable forward rotations of the dial menus for locking said impulse wheel against rotation, and means controlled by tlie'a'linl for releaeing the impulse wheel.

13. in a calling device :1 tlial provided with continuous line of linger holds an tion, connecting means he wheel and the dial for rotating the Wheel a :listance each time upon the fox-weal rotation of the (ligil means for locking the impulse wheel against rotation, uncl means controlled by the dial for releasing the impulse wheel. v

Signed b me at Ch. Cool; county, lllizio' this 8 Joy of 1908.

Jo nt iieioireoit

Images