US643545A - Telephone-telegraph. - Google Patents

Description

No. 643,545. Patented Feb. l3, I900.

A. SINDING-LARSEN.

TELEPHONE-TELEGRAPH.

(Application filed Aug. 22, 1899.)

(No Model.) 2 sums-sheet 1.

NITED STATES ALF SINDING-LARSEN, OF FRE DRIKSVAERN, NORWAY.

TELEPHON E-TELEG RAPH.

SPECIFICATION forming part of Letters Patent N 0. 643,545, dated February 13, 1900.

Application filed August 22, 1899.

To all whom it may concern.-

Be it known that I, ALF SINDING-LARSEN, a citizen of the Kingdom of Sweden and Norway, residing at Fredriksvaern, Norway, have invented certain new and useful Improvements in Telephone-Telegraphs; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention has relation to telephone sys tems, and these as now generally organized present various inconveniences, one of which lies in the impossibility of advising a called subscriber of the fact of having been called during his absence. To remedy this inconvenience, it has been proposed to combine a phonographic recording instrument with the telephone receiver and provide .suitable mechanism for operating the recording-cylinder. In such an arrangement it is, however, necessary that the subscriber before absenting himself should switch the recording mechanism into the telephone-receiver circuit, and should he omit to do so the recorder becomes useless. A further inconvenience and one that is often a very serious one lies in the possibility of the attendant at the central to obtain knowledge of all'messages sent by one subscriber to another.

My invention has for its object, first, to provide a telegraphic recording apparatus at each subscribers station so organized as to require no attention should it be necessary for the subscriber to absent himself or should he desire to obtain a telegraphic record of messages transmitted to him. My invention has for its further object the provision of means whereby. the obtaining knowledge of messages sent through the line by an attendant at the central becomes impossible.

To render practicable the combination of a telegraphic system with a telephonic system, the following conditions should prevail: First, the transmission of telegraphic messages should in no manner influence the calling-off devices at the central; second, no means should be required for connecting the telegraphic recorder with the telephone system by hand; third, the telegraphic system should be so organized as not to interfere in any manner with the use of the telephone Serial No. 728,064. (No model.)

system in the ordinary manner; fourth, the telegraphic receiver or recorder should be so organized as to be applicable to existing telephone systems, and, fifth, the construction of the telegraphic receiver and its combination with the telephone system should be simple and cheap.

In the telephone system to be described and embodying my invention all of the above conditions prevail. The first and second conditions are fulfilled by using a magnet as an armature for the indicator-magnet at the central and by using the call-magnet indicator at the local stations as a transmitter for telegraphic impulses, means being provided for transmitting current impulses of one direction only when telegraphin g a message, so that the armature of the indicator-magnet at the central will remain uninfluenced, thereby rendering it impossible for an attendant at the central to obtain knowedge of a telegraphic message transmitted by one subscriber to another, and, finally, by providing an auxiliary armature for the call-bell magnet acting as a circuit-closer for the telegraphic-receiver circuit. The fulfilment of the third, fourth, and fifth conditions is selfevident from the description of the two systems, reference being had to the accompanying drawings, in which- Figure 1 shows diagrammatically the combination of a telegraphic receiver or recorder with a telephone-receiver, the usual transmitter or microphone being omitted, it being unnecessary to a full understanding of my invention; and Fig. 2 is an elevation of the telegraphic receiver or recorder, its inclosing casing being shown in section. Fig. 3 shows a record-strip in which the record is made crosswise instead of lengthwise.

Referring to Fig. 1, 0 indicates the central station,and S and S two subscribers stations, whose local circuits are connected at 3 3 with the main lines 2 2, respectively. The cir: cuits and appliances at both subscribers stations being alike, I have indicated the same by like symbols of reference, distinguishing the parts at one station from those at the other by the addition of an affix to the said symbols.

M indicates the call-circuit magneto-inductor; m, the call-bell magnet; a, its armature;-

Z),the bell-clapper,vibrating when in operation between contacts (1 and e; A, the auxiliary armature of said call-bell magnet m, constructed in the form of a circuit-closing lever for the circuit 30 of the telegraphic receiver or recorder T, and S indicates a switch-lever adapted to be moved into contact with the contact f or the contact g, said lever being normally in contact with f, and R indicates the telephone-receiver, and 1' its switch-lever.

It being supposed that S is'the transmitting-station and S the receiving-station and that the switch-levers S and S at both stations are in contact with their respective c011- tacts f and f, this being shown in dotted lines at the transmittingstation, and the latter calls the central, current will flow from magneto-inductor H, via wire 4, to bell-magnet-s m, wire 5 to switch S, contact f, wire 6 to connection 3, line 2 to central, whereat the indicator-magnet will actuate its armature, and thereby the indicator drop, because alternating-current impulses are sent through the line. If now the central calls station S current will flow via line 2 to point 3, wire 6, contact f, wire 5, bell-magnets m, wire 4, magneto-inductor M, wire 7', telephone switchlever 7", wires 8 9 to earth at E, thereby actuating the call-bell. Should the subscriber at the receiving-station be absent, or should he desire to have the message sent telegraphically and so recorded, he simply refrains from answering the call, and the central places the transmitting-station in communication with the receiving-station, in which case the subscriber at said transmitting-station shifts the switch-lever S from coutactf to contact g. If the sender now turns the crank of the magneto-indicator M, which crank for the purpose of telegraphing is provided, preferably, with a small hand-wheel, current will flow as follows: from magneto-indicator M, via wire 4: to the call-bell magnets on, wire 5 to switchlever S, contact g, bell-clapper armature a, and bell-clapper I). Should said clapper at this time be in contactwith contact 6, the current impulse of one direction will flow from c to earth at E through wire 9. lVhen, on the contrary, the clapper b is in contact with d, the current impulse of opposite direction will flow through b d, branch wire 11, point 3, line 2, through the central station 0 to the receiving-station S by way of line 2, point 3, branch wire 6, contact f, switch S, wire 5', bell-magnets m, wire 4', magneto-inductor M, wire '7, telephone-switch 7', wires 8' and 9" to earth at E. The current passing through electromagnets m will energize the same, thereby causing circuit-closing armature A to be attracted to close the telegraphicrecorder circuit 30, as shown at station S and as it requires alternating currents to actuate the call-bell clapper b the latter will remain at rest for the reason that unidirected currents only pass through the coils, maintaining the magnets at the same polarity, so that when the armature a is in its normal position of rest, as shown, one end will be in contact with the magnet and remain so until a reverse current is sent through the spools.

Inasmuch as current impulses of one direction are conducted to earth and currents of opposite direction alone caused to flow through the line by the alternate shifting of the bell-clapper b fro m contact 61 to contact c, or vice versa, due to the alternating currents produced by the magneto-inductor, the armature of the indicator-magnet at the central will not be influenced by such direct-current impulses. Hence the attendant at the central cannot obtain knowledge of the message transmitted by the means usually available.

The use of the magneto-inductor as a telegraphic transmitter simplifies the organization of the system very materially. Yet I desire it to be understood that I do not limit myself to such use, as a special transmitter could be included in the circuits without difficulty or in the circuit of a local battery, in which case all relay arrangements can be dispensed with, as direct-current impulses only would then be sent through the line. The same applies to the circuit-closing devices for the local circuits and to the combination with the bell-clapper of the contacts (Z and e, for which devices special appliances could be sub stituted, though this would materially complicate the organization of the systems.

As regards the telegraphic receiver or recorder, it is preferably so organized as to be operated by current impulses from a battery B in a local circuit 30, as shown. I am thus enabled to materially simplify the construction of the instrument, as shown in Fig. 2. Referring now to said Fig. 2,in the telegraphicrecorder circuit 30 are included two electromagnets 21 and 3l,the contact 29,the armature A, and the local battery B, Fig. 1. The armature 22 of the electromagnet 21 carries a tracer 23 or is other wise constructed to trace upon or indentor cut code-symbols into a fillet of paper 33as, for instance, Morse-code symbols41 being the retracting-spring of said armature. 32 indicates the roll on which is wound a fillet of paper 33, that is guided over a revoluble platen 24, the guide-roller 25, over a guideboard 34, and out of a slot 35 in the casing 36, containing the recording appliances. On a shaft 37 is secured a ratchetwheel 16 and a gear-wheel 38 in gear with a transmitting-wheel 39, meshing with a pinion 40 on the shaft of the feed-roll 26 in frictional contact with the guide-roll 25. On the aforesaid shaft 37 is loosely mounted an armaturelever 14, whose shoe 13 is influenced by the pole 12 of the electromagnet 31, and said armature-lever has a short arm 17 projecting from its hub, adapted to engage a pin 18, projectin g from a pawl-lever 15,1oose on the arbor 37. To the lever 15 is pivoted a pawl 20, engaging the ratchet-wheel 16, and to the free end' of said lever is connected a retractingspring 19. It will thus be seen that at each closure of the circuit 30 the electromagnot 21 is energized and the armature-lever 22 attracted, thereby moving the style 23 out of contact with the paper fillet'33 on platen 24. At the same time the electromagnet 31 will be energized and the armature-lever 15 will be attracted, thereby moving said armaturelever 15 against thestress of its spring 19, together with the pawl 20,a given distance from right to left. When the circuit is nowinterrupted, the electromagnets 21 and 31 are demagnetized, the spring 41 of the style armature-lever 22 will move the same into contact with the paper fillet on platen 24, the arma ture-lever 14 drops back into its normal position, and the spring 19 will draw the pawllever from left to right, thereby revolving the ratchet wheel in the same direction and through the feed-gearing 38, 39, and revolving the feed-drum 26, drawing the fillet of paper along, and as the tracer or style is in contact with said fillet of paper a dot or a longer or shorter dash will be produced by the style in or on the paper fillet, according to the length of time the style remains in contact with said fillet of paper.

It will be seen that the character of the record-symbols-dot or dash of greater or less length-does not depend, as usual, on the length of time during which the circuit remains closed, but on the length of time the circuit remains open between current impulses.

In the apparatus shown in Fig. 2 the symbols are formed lengthwise of the fillet of paper; but if the style were arranged to vibrate crosswise of the record-paper then the record would be produced in a like direction, as shown in Fig. 3.

Having thus described my invention, what I claim as new therein, and desire to secure by Letters Patent, is

1. In a telephone system, the combination with the main line, of a local receiver branch and a grounded signaling branch, an electromagnet in the latter branch, two armatures therefor, one actuating the signal and the other closing an independent circuit, a source of alternating current, and means for directin g either alternating or unidirected currents to line from an alternating-current source, and to receive either alternating or unidirected currents to operate the signal or the circuit-closer, substantially as set forth.

2. In a telephone system, the combination with the main line, local receiver, and signal branches; of mechanism for closing an independent circuit, a grounded and a line-connected contact, a vibrating conductor, an armature and its magnet, said conductor and armature adapted to direct unidirected currents from an alternating source to line to operate the circuit-closing mechanism at the receiving-station, and a hand phone-carrying lever adapted to ground either of .theaforesaid branches, substantially as set forth.

3. The combination with the main line, the

telephone-receiver and call-circuits and a local battery-circuit at a subscribers station, the call-bell magnet, and means for transmitting or receiving through said magnet either alternating or direct current impulses; of a telegraphic-receiver circuit an armature-le ver operated bysaid magnet when energized by direct-current impulses to close the telegraphicreceiver circuit, for the purpose set forth. 4. The combination with the main line, the call-circuit at a subscribers station, the callbell magnet, its armature, the bell-hammer actuated thereby, and the alternating-current generator in said call-circuit; of a branch from the main line, having a contact-terminal, a ground connection having a like terminal between which terminals the bell-hammer is arranged to vibrate, whereby currents of one direction may be grounded, and currents of an opposite direction sent to line, for the purpose set forth.

5. The combination with the main line, the telephone-receiver and call-circuits and a local battery-circuit including a telegraphic re ceiver at a subscribers stat-ion, the call=bell electromagnet, a branch from the main line having a contact-terminal, a ground-line having a like terminal, the bell-hammer arranged to vibrate between said contacts and the al ternating-current generator in the call-circuit; of an armature-lever controlled by the call-bell magnet and operating to close the telegraphic circuit, whereby alternating currents, or currents of one direction may be caused to flow through said magnet, for the purposes set forth.

6. In a telephone system, a local signal branch, signal-operating magnets included therein, an auxiliary armature therefor, in combination with a local circuit adapted to be closed by said armature, a magnet operating a spring-retracted stylus, in series in said circuit with a second magnet, a platen, a train of gearing operating a feed mechanism, said second magnet adapted to impart a step-bystep movement to the gearing, substantially as described.

In witness whereof I have hereunto set my hand in presence of two witnesses.

ALF SINDING-LARSEN.

Witnesses:

HENRY BORDEWICH, J OH. VAALER.

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