US1747210A - Telechronometer - Google Patents

Telechronometer Download PDF

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US1747210A
US1747210A US508037A US50803721A US1747210A US 1747210 A US1747210 A US 1747210A US 508037 A US508037 A US 508037A US 50803721 A US50803721 A US 50803721A US 1747210 A US1747210 A US 1747210A
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magnet
meter
line
current
pivot
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US508037A
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Babcock Garrison
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AMERICAN TELECHRONOMETER Co
AMERICAN TELECHRONOMETER COMPA
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AMERICAN TELECHRONOMETER COMPA
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Priority to US352983A priority patent/US1821086A/en
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M3/00Automatic or semi-automatic exchanges
    • H04M3/08Indicating faults in circuits or apparatus
    • H04M3/12Marking faulty circuits "busy"; Enabling equipment to disengage itself from faulty circuits ; Using redundant circuits; Response of a circuit, apparatus or system to an error

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  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Details Of Flowmeters (AREA)

Description

Feb. 418, 1930. G. BABCOCK I TELECHRONOMETER Filed 001'.. 15, 1921 5 SheetswSheet 2 Feb. 13, i930.
s. BABCOCK 'TELECHRONOMETER Filed cgt. 15. 1921 Feb 1%, w3@ Q BAQQCK TELECHRONOMETER Filed om. 15, '1921, 5 sheets-sheet 5 Patented Feb. 18, 193() y UNITED STATES PATENT OFFICE GABBIBON BABCOCX, OF EVERETT, WASHINGTON, ASSIGNOR T AMERICAN TELE- CHRONOMETEB COMPANY TELECHBONOIETER Application led October 15, 1921. Serial No. 508,037.
My invention relates to means for meterlng and registering the number of time units c onsumed by a flow of current in an electrical circuit, and is concerned particularly with a novel and improved form of reversal responsive metering device of the type known under the trade name of Telechronometer for measuring and registering the time units consumed by a message in a telephone system employing means for converting or securmg reversals of current flow and for applying them to the meter.
lVhile my present invention is particularly directed to a novel and improved form of meter, especially adapted for use in telephone systems and the manner in which it is employed in a system having periodic reversals of current flow over the calling line, it is not limited to employment vin telephone systems,
or if employed in a telephone system, it 1s not limited to employment in the specific telephone system,l nor to the particular' manner of employment i. e., method of connection and application, which I have elected to describe in the following specification.
My present invention lwhich is' along the line of the invention 'set out in m co-pending application, Serial No. 476,712, led June 11, 1921 provides primarily an improved operating element which, while compact is powerful and of a simple and rugged character. The meter of my present invention employs two stationary operating coils of a novel form and arrangement, which, as in my above copending application, are connected serially, one in each side of the line, whereby the circuit is balanced and the transmission thereby improved. The metering arrangement of my present invention` as in my co-pending application, makes surreptitious or accidental shunting of the meter practically impossible. My present invention provides in addition to a novel and improved form of operating element a novel and improved arrangement of simple, compact, rugged and reliable character for registering the number of time units consumed by a conversation or connection.
Certain constructional features and arrangements of my present invention, which aims` to standardize a meter of the telechronometer type, are novel and important, and these together with such other provisions as have not been already set forth will appear from the following detailed description, taken with an inspection ot' the accompanying drawings, in which I have disclosed a particular embodiment of my invention in order to explain more fully to those skilled in the art how to construct and practice the same.
In the drawings:
Figure 1 is a diagrammatic illustration o'f a telephone system, embodying my invention;
Figure 2 is a face view (front elevation) of a meter embodying my invention;
Figure 3 is a bottom side elevational view of the same;
Figure 4 is an end elevational view, partially broken away, to show the manner of mounting the meter;
Figure 5 is an enlarged face view with the cover or lid removed;
Figure 6 is an enlarged horizontal sectional view through the housing or casing of the meter substantially on the line 6-6 of Figure 2 showing the metering mechanism therewithin in elevation;
Figure 7 is an isometric view of the magnet holder employed;
Figure 8 is an ispmetric view of net;
Figure 9 is an isometric view of the coil spool showing the arrangement and insulation of the coils thereon in section; and
Figure 10 is an isometric View of one of the magnet bumpers.
As illustrated in Figure 1, the system in which my invention is embodied comprises a calling sub-station A, called sub-station B, and connecting cord circuit C, located preferably at a central switchboard.
The calling sub-station A comprises -a transmitter 1, induction coil 2, automatic switch hook 3, receiver 4 and a suitable call bell 5. In addition, I provide a meter 6, having its coils 7 and 8 connected serially in the two limbs of the subscribers line. The sub-station A is connected by suitable line wires 9 and l() to line signaling and switching apparatus in a manner, which will be the magdescribed more in detail as this description proceeds.
The meter 6, per se, which is shown in detail in Figures 2 to 10, inclusive, comprises a permanent magnet l1 of general rectangu- .lar form havingvits opposite ends brought relatively near each other.` The parallel arms 12 of a channel shaped pole piece 13 secured portions of the permanent magnet 11 are mounted in openings 15 in a magnet holder 16, and'securely clamped therein as by means of suitable screws 17 or the like (Figures 5 and 6) for the reception of which screws 17 suitable openings 18 are provided. A pivot post` or spindle 19 forms the pivot about which the magnet holder 16 is adapted for rocking movement, back and forth in accordance with the prevailing polarity in the coils 7 and 8. The coils 7 and 8 surround the end or pole 14 of the magnet 11, and are embraced by the armsk 12 projecting from the opposite end or pole thereof. These coils 7 and 8 are so connected and mounted in the line wires 9 and 10, that they tend to produce the proper polarity cumulatively to swing the magnet 11 about the pivot 19 to the position corresponding to the polarity impressed upon the lines 9 and 10.
The metering mechanism is enclosed in a housing or casing 20 comprising a bottom casing portion 21, and an upper casing or lid portion 22. The upper edge of the bottom casing portion 21 is flared out as shown at 23 to provide a peripheral seat for a frame, or meter mechanism carrying plate 24, which is mounted in this upper flared portion 23 of the casing portion 21. Apertures 25 at the projecting ear portions 24 of the plate 24 register with similar apertures in flanges or ledge portions 26 formed integral withthe lower casing portion 21. The peripheral flange or lip 23 is cut away to provide room for the apertured ears 25. The meter is mounted upon a mounting board 27 or other suitable support by means of mounting posts 28 and suitable screws 29, the posts 28 having upper reduced ends extending into the registering apertures in the plate 24 and ianges or ledge portions 26 substantially as -shown in Figure 4. The upper casing portionor lid 22,* is provided with a skirt 30 'which covers the upper iared edge 23 of the bottom 21. vThe lid 22 is provided with an opening through which the indicating devices 31, and 33 may be viewed. A glass or other sultable covering 34ifor this opening is clamped inplace by means of suitable clamping arms 35 bolted or otherwise suitably secured to from the underside of the plate 24. A lock nut 43 locks pivot bearing 41 in place. The coils 7 and 8 are'wound upon a common spool 45 mounted on a bracket 46 which is fastened by screws 47 upon the underside of the mount# ing plate 24. The coils 7 and 8 are'preferably Wound and insulated as shownsin igure 9. They may, however, be wound and insulated in any other'desired manner.-
The magnet holder V16 is provided' vwithv a pair of ratchet pawls 50 and 51 (Figures 5 and 6) mounted upon pins 52 which pins.
52 are in turn secured in openings 53 in the face 54 of the holder 16. The pawls 50 and 51 cooperate with a ratchet 56 fixed upon a shaft 57 journaled at its'lower end in' a bracket member 58 secured to the frame plate 24, and at its oppositeend in the'frame of the indicating devices. The shaft 57 carries a pinion at its upper end through which pinion 85 movement of the shaft 57 is trans-l mitted to the unit wheel 33.- A suitable driving mechanism such as Geneva gears, or the like, transmits the motion, to the indicating devices 31, 32 to register multiples of the counts registered upon the unit wheel 3,3. The pawls 50 and 51 and ratchet 56 provide an actuating device or escapement which requires two movementsfor a complete registration of a unit, namely, pivotal movement of the 'magnet holdery 15. about its pivot19. to
one position -andthcreafter, pivotal movement of the magnet holder 15, about its pivot 19, to the reverse position, to register a count upon the unit wheel 33. In other words, the ratchet 56 is advanced part way by .the pawl 50 upon movement of the holder 16 in a clockwise direction (Figure 5) about its pivot 19 and the advance is completed by motion-,of the pawl 51 upon movement of the holder ina counter-clockwise direction about its pivot 19. The magnet 11 is properly balanced by a balance rod or bar 60 extending through and secured .as by meansof a suitable set screw 62 (Figure 5) in a lug 61 extending from one end of the holder 16. .This rod is adjustable to bring two ends of the magnet on opposite sides of the pivot into balance. As the meter is mounted in the position shown in Fig. 2 the adjustment of rod 60 isV able to bring the movable system to a balance. The driving mechanism between the shaft 57 and the indicating devices 31, 32 and 33 is mounted between a bottom plate and a top plate 66 secured together in the form of a frame by means oflsuitable posts 68, which posts in the particular arrangement illustrated are riveted in the bottom plate 65 and carry the top plate 66 at their upper ends as through suitable screws 69. The bottom plate 65 is mounted upon the upper surface of the frame plate 24 as by means of suitable screws 70, being spaced-from the plate 24 by means of suitable collars 70.
The front edge ofthe frame plate 24 is recessed or cut away along the dotted line 71, shown in Figure 5 and a terminal block 73 of bakelite or other suitable insulating material extends across and into the opening provided, and is secured at its opposite ends, as by means of screws 72 to the frame plate 24.. The terminal block 7 3 is provided with a portion depending into the cut away portion of the plate 24, a vertical flange 74 along its forward edge and a pair of conductor receiving lugs 75 extending forwardly'therefrom. Terminal strips 76 mounted upon the terminal block 7 3 provide for connecting the coils 7 and 8 serially in the two limbs of the subscribers line as vshown in Figure 1. vThe 'forward reduced ends of the terminals 76 extend or are bent down through openings 78 in the block l73 to facilitate connection with the terminals of the coils 7 and 8. The' line wires 9 and 10, or terminals thereof, are led in and out through the lugs 75 and connected to the terminal strips76, as by securing them beneath the screws or bolts 76'.
A pair of bumpers 80 and 81 secured to and depending from the frame plate 24 are provided for the magnet 11. The lower ends of these bumpers are bent back as shown at 82 in Figure 10, to securely grasp and hold a piece of felt, billiard cloth or other suitable padding 83 wrapped thereabout.
The shaft 57 carries a pinion 85 at its upper end through whichpinion 85 motion is transmitted to the units wheel 33 and then to the wheels 32 and 31 through the registering mechanism already described.
The calling subscribers line is provided with the usual line signal 90, controlled by a line relay'91, and also governed by a cut-ott relay 92 as is well known in the art. Suitable terminals, such as the multiple -jacks 93, and the answering jacks 94, are connected to the line wires 9 and 10, for the purpose of.
making a connection with central, or with another subscriber as may be desired. The sub-station B of the called subscriber in the particular lsystem shown is provided with similar apparatus, the parts of which are designated by primed reference numerals corresponding to those of the calling line. The sub'scribers lines are supplied. with current from a central battery 95 which also supplies current for the central apparatus.
The apparatus at the centralstation comprises a cord circuit having an answering plug 96 and a ringing plug 97. The two ends ofthe cord circuit are separated by condensers 98` and 99, and the se )arate ends are supplied with battery throug i the supervisory relays 100 and 101. The respective ends of the cord circuit are provided with supervisory signals 102 and 103 respectively, these signals being alsocontrolled by the sleeve relays, 104 and 105 respectively.
The answering end of the cord. circuit C is provided with connections to the operators talking set 106, through a suitable listening key 107, and the ringing end of the cord circuit is provided with connections to a ringing generator 108 through a suitable ringing key 109.
Current is supplied to the talking strands of the cord circuit upon the ringing end, through a supervisory relay 101 directly, so as to provide uni-directional ow of current over the called line, and current is supplied to the answering end of the cord circuit through a time controlled current How reversing device indicated generally by the reference character 115 for securing periodic reversals of current How over the calling line for operating the register 0r meter 6 at the substation of the calling party. The answering end of thecord circuit may be provided with uni-directional current until such time as the called party answers if desired.
The particular pole changer device or current converter 115 illustrated is described and claimed in my co-pending application, Serial No. 508,038, tiled Oct. 15, 1921. Any other suitable pole changing devicev may be employed. v
The pole changing device illustrated comprises two pairs ot compression rheostats R1, R2 and R3, R'i between which battery 95 is connected over conductors 116 and 117. The terminals 118 and 119 of the pole changer lead to the talkinor strands 120 and 121 respectively, through the supervisory relay 100. The rheostzits shown are of the carbon pile type well known in the art. The resistance of these piles is lowered or decreasedupon compressing the same, and is increased when the pressure thereupon is released.
One terminal of the battery 95 is connected with the lower ends of the rheostats R1, R3. rlhe upper end of the rheostats R1 is connected with the terminal 119 of the pole changer. The upper end of the rheostat R3 is connected with the terminal 118. The lower ends of the rheostats R2 and R4' are connected to the opposite terminal of the battery 95. It will' now beapparent that if the resistance of Isn hibit a strong positivepotential while the terminal 119 will exhibit a strong negative potential. If now -the pressure on rheostats R1 and R2 is relaxed or released and simultaneously the pressure onrheostats R3 and R*1 is increased, the terminal 118 will exhibit a strong negative potential while the terminal 119 will exhibit a strong positive pot!` ntial. The change from one potential to the other is performed without any interruption or abrupt change in the current flow.
A balance indicator 130 between the line and the battery enables the attendant to observe any out of balance condition in the rheostats, so that the same may be readily adjusted to a balance as more fully explained in my last referred to copending application. To further assist in the adjustment of the rheostats, Iprovide a voltmeter 131 for indicating to theattendant the performance or operation of any of the individual rheostats. A suitable switch 132 is adapted for connecting either of the rheostats R1, R2, R3 or R4 individually across the voltmeter 131.
The arrangement for actuating or compressing the pairs of resistances, comprises a pressure cylinder 135' for the rheostat R1, R2 and pressure cylinder 136 for the rheostats R3, R4. Piston rods 150 and 151 'connected at their inner ends to suitable pistons within the cylinders 135 and 136, respectively, are adjustably connected at 152 and 153 with rheostat actuating shoes 154 and 155. Actuation of the respective rheostats is had by engagement of these actuating shoes with insulated' buttons projecting. from the lower ends of the rheostats. ,The supply of compressed air or other suitable motive fluid from a common supply conduit 156 to the cylinders 135 and 136 is regulated by suitable adjustable pressure regulators 157 and 158. Conduits 166 and 167 provide exhaust outlets for discharging or exhausting the pressure from the chambers 135 and 136 while suitable i valve members 162 and 163 control the flow to and exhaust from the respective cylinders. The cylinders 135 and 136 are provided with suitable pressure gauges 164 and 165 respectively.
The adjustable connections 152 and 153 between the outer ends of the piston rods and the actuating shoes 154 and 155 as well as the manner whereby the actuation of one pair of rheostats relative the other may be varied by means of the regulators 157 and 158 and the degree of actuation of any resistance relative the other of the same set adjusted is more fully expained in said companion application No. 508,038.
'lhe'lactuating arms 170 and 171 for controlling the valves 162 and 163 respectively, are connected at their free ends to the opposite ends of a link 172, which link 172 is connected by a pin joint at its center to the upper end of an actuating lever 17 3. A pair of bridging contact fingers 174 and 175 car# ried by the opposite end of the bar 173 are adapted for bridging terminals 17 6, k 177 and 178, 179 of a valve actuating circuit. The lever 17 3 is pivotally mounted centrally and is rigidly joined to a rocker arm 180. The rocker arm 180 is connected at its opposite ends through suitable links with the plungers or cores of a pair of solenoids 137, 138. The
terminals 177 and 179 are grounded as shown at 181 v(Fig. 1). The circuits through the solenoid windings 137 and 138 are controlled by a pair of time controlled relays 139 and 140. The windings of the relays 139 and 140 are connected at one end of a battery 182 or yother suitable source of current, which source is grounded as shown at 183. The circuits through the relays 139 and 140 are governed by a time controlled circuit controller, which includes a cam wheel 141 mounted, for example, on the second shaft of a standard clock and contacts 142 and 143 which are 'alternately closed by engagement of the cam portions of the wheel 141 therewith. The cam wheel 141 has two dwells substantially 180 degrees apart so that ,they
current of normal potential upon the line wires 9 and 10 energizing line relay 91 and line signal 90 whereupon the operator makes a connection with the answering plug 96 with the line of the calling subscriber through the answering jack 94, thereby effacing the calling signal 90, disconnecting the line conductors 9 and 10 from the battery 95 by means of the line relay 92 and applying the potential prevailing in the strands 120 and 121 of the cord circuit employed.
The normal current in the line wires 9 and 10 moves the magnet 11 of the telechronometer 6 about its pivot 19 in one direction. A reversal of current in the lines 9, 10 causes the magnet 11 to move about its pivot 19 in the opposite direction, thereby completing the cycle of operation necessary to make the registration on the telechronometer 6.
The operator at central, connects her` talking sets 106 and receives the order for connection from the subscriber A whereupon she selects the multiple jack 190 of the called subscriber B and makes connection thereto with the ringing plug 97, applying ringing current by means of the key 109 and generator 108. As soon as the called subscriber B answers, the supervisor signal 103 is etfaced and the parties carry on their conversation. Meanwhile, periodical reversals of current are occurring on the calling line, these cycles of reversals being registered as counts upon the meter 6.
Movement of the permanent magnet 11 about its pivot 19 to register the cycles of reversals as counts upon the meter is eifected as follows:
The arrangement of the pole 14 of the magnet 11 between the arms 12-12 of the pole piece 13 at the opposite end of the magnet sets up, or creates a magnetic field the lines of force of which travel in a horizontal plane, Figures 1 and 5, between the arms 12-12 of the pole piece 13 and the pole 14 arranged therebetween. Then, according to the Right-hand rule well known in the n art when a How of current is set up through the coils 7, 8 in a counterclockwise direction, looking down from the top upon the meter as shown in Figures 1 and 5, the poles of the magnet will be moved upwardly, moving the magnet 11 in a clockwise direction about its pivot 19. When the direction of flow of current through the coils 7, 8 is reversed, i. e. set up in a clockwise direction looking down upon the meter from the top as before, the poles of the magnet will be moved downwardly, moving the magnet in a counterclockwise direction about its pivot 19. The periodical reversals of current flow occuring i on the calling line thereby cause successive pivotal movements of the magnet 11 about its pivot 19 first to one extreme position, and then to the other extreme position. Upon pivotal movement of the magnet in a clockwise direction, looking from the front in Figures 1 and 5, the ratchet 56 is advanced part way by the pawl and the advance is completed by the pawl 51 upon movement of the magnet 11 in a counter-clockwise direction, as has already been set out.
In the particular system illustrated, the calling party is charged for all of the time consumed in making a connection and consnmmating the conversation. It is to be understood. however, that the charge may be for only the time during which the connection between the parties is established. This may be accomplished by cutting the terminals of the pole changer into the talking circuit of the calling line through the contacts of the superthe solenoid windings 137 and 138. The closing of these circuits is only momentary, suficient to operate the valves 162 and 163 and set the connecting piece or bridge carreid by the arm 173 for closing the other circuit. The operation of the valves 162 and 163 in turn controls release of one set of rheostats and compression of the other set. A complete cycle of change of polarity occurring in the calling line from positive to negative and back to positive or vice versa causes an actuation or registration upon the meter 6 at the calling station.
It will now be apparent that as in my copending application the placing of the two coils of the telechronometer in the two sides of the telephone line balances the circuit and secures better transmission and more positive operation. Surreptitious shunting of the meter is made diicult by the double coil arrangement. The arrangement of these coils has been standardized as have the other parts and the close spacing of the poles of the magnet maintained. The pivotal mounting of the magnet has eliminated the additional armature used before. In addition, an improved counter actuating arrangement has been provided. The magnet needs very little iow to move from one extreme position to the other and the entire meter is compact, powerful and of a simple and rugged character.
No springs for the pawls are employed since the placing of the meter in proper position permits the pawls to function properly by their own weight.
I do not intend that the invention shall be limited to telephone systems nor to use in connection with the particular current reversing arrangement described. Neither do I intend to be limited to the precise details of construction in the meter itself which I have shown and described.
I claim:
1. In combination, a mechanism, a housing enclosing said mechanism, a frame plate within said housing, mounting means for the housing, said mounting means including a post projecting through a portion of the housing and into an opening in said mounting plate, a cover for the housing, and a screw cooperating with said post and inaccessible when said cover is closed.
2. In combination, an enclosing housing, a frame plate within said housing, mounting means for the housing, said mounting means including a post having a reduced end portion projecting into the housing and into an opening in the frame plate, said reduced end portion providing a shoulder for cooperation with the housing, a cover for the housing and a screw threaded into the reduced end of the mountingrpost, said screw cooperating with the frame plate and being inaccessible when the cover is closed.
3. In combination, a magnet holder having a pair of openings for the reception of the legs of a magnet, said magnet holder carrying a pivot post and a pair of actuating pawls mounted upon said holder.
4. In a device of the class described, a magnet holder, a magnet of generally rectangular form having opposite legs carried by said holder, a pivot yfor said holder, a coil at one corner of the magnet for swinging same about said pivot, and actuating means on said holder.
In Witness whereof, I hereunto subscribe my name this 6th day of October, 1921.
GARRISON BABCOCK.
US508037A 1921-10-15 1921-10-15 Telechronometer Expired - Lifetime US1747210A (en)

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US352983A US1821086A (en) 1921-10-15 1929-04-06 Telechronometer

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4727577A (en) * 1986-05-30 1988-02-23 American Telephone And Telegraph Company, At&T Bell Laboratories Method of and apparatus for recording information on the accumulated usage of a trunk
US20210316658A1 (en) * 2018-09-26 2021-10-14 Daimay North America Automotive, Inc. Sun visor with magnetic switch

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4727577A (en) * 1986-05-30 1988-02-23 American Telephone And Telegraph Company, At&T Bell Laboratories Method of and apparatus for recording information on the accumulated usage of a trunk
US20210316658A1 (en) * 2018-09-26 2021-10-14 Daimay North America Automotive, Inc. Sun visor with magnetic switch
US11858417B2 (en) * 2018-09-26 2024-01-02 Daimay North America Automotive, Inc. Sun visor with magnetic switch

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