US1823978A - Telegraph or teletyper plant - Google Patents

Description

Sept. 22, 1931. V w A, JIPP 1,823,978

TELEGRAPH OR TELHTYPER PLANT Filed Feb. '18, 1929 xi 0 *1 l iwi? w N F 7%; F" a *9 y I w a I Y v izxfrai Patented Sept. 22, 1931 UNITED STATES PATENT OFFICE AUGUST J'IIPP, OF SPAN'DA U, BERLIN, GERMANY, ASSIGNOB '10 SIEMENS &

HALSKE, AKTIENGESELLSCHAI'T, OF SIIMENBSTADT, NEAR BERLIN, GERMANY, A

CORPORATION OF GERMANY TETIEGBAPK )3 TELETYPER PLANT Application filed February 18, 1928, Serial llo. 340,888, and in Germany February 18, 1828.

The invention relates to improvements in the connection over a special line not used durin the selector or telegraph operation, in or er to enable the necessary differentiation to be made between the current impulses for the various purposes (selector, telegraph, selector resetting impulse) used in the operation of the plant.

To enable the resetting of the selectors to be made over the lines used for the selector and telegraph operation, according to my invention the resetting of the automatic selectors takes place by impulses. the conditions or nature of which (such as the type of current, frequency) are difl'erent from those of the selector or telegraph currents.

In this way it is possible to manage even with two conductors only of an ordinary telephone cable line, audio frequency or subaud1o frequency communication bemg preferably used in view of the telephone service, which also allows multiplex utilization of the lines.

The different condition of the selector resettin currents may, for instance, be attaine by employing alternating'current'in contrast with the direct current of the seoperative or rest position temporarily to pass into the operative or working position, a difference in the duration of the impulses may be effected by bringing the armatures after the termination of telegraphic traific i. e.

after the return into the inoperative p0si-' tion permanently into the operative position, whereby a permanent im ulse is given, which is utilized for the tripping of the resetting relay and, if necessary of other parts of the apparatus, such as a switchgear controlling the driving motor. The armatures are thus brought into a false position of rest differing from the true position of rest. Since polarized relays mainly come into account, the armatures remain in the falseposition of rest even after switching ofl the total operating current and the giving up of this pos tion when the current is switched on again may also be used for releasin operations on the receivin side. The t rowing of the relay from the alse into the true position of rest is preferably efi'ected by a condenser impulse released on switchin on the motor of the telegraph apparatus, w ich ex cites an auxiliary winding of the transmitter relay and throws its armature over, whereby the receiving relay is also chan ed over and a pre-selector switched in. A r this preselection, which takes place automaticall the subscriber may proceed to select with h1s dial. In order to maintain the connection,

. while the telegraph relay is in its true position of rest or vibrates synchronously with the telegra h or selector impulses, retarding means, suc as slow-acting relays, are employed which, while the armature is in the false position of rest, are not excited and maintain the circuit closed for the duration of the connection. The slow-acting relay closes the circuit of the re-selector for the duration of the connectlon and when deexcited releases in well known manner the tripping devices of the pre-selector and the other line selectors.

Two embodiments of my invention are diagrammatically illustrated in the draw-' ings aflixed hereto and forming part of my specification. In the drawings,

Fig. 1 is a simplified diagram of connections of an exchange according to my invention, and

Fig. 2 is "a diagram of my improved arrangement of relays. I

In "telegraphy various transmitting systems are used. The most important ones are the diplex system (1), the duplex system (2), and the duplex-diplex system (3). All these systems have, however, the resolution in the local circuit in four lines in common, one pair of which transmits messages in one direction and the other pair in the op osite direction. A fifth unsymmetrical con uctor serves only for secondary purposes of the in-. ternal automatic connection. If the selector afiparatus is thus carried out for four lines,

station by trunk lines L is indicated by the reference letters S or E respectively. The subscribers station 2 possesses the usual line balance N.

For sending out selector impulses by the subscriber, there is provided at the subscriber station a number dial D which controls the alternating contact at upon operation of the dial and the alternating contact (2 upon release of the dial. The contact d operates to disconnect the sending relay S during the selection, from the contact T controlled by the teletyper ap aratus, and to connect such relay .4 with the impulse contact d A two-pole reversing switch A is arranged in the circuit ofrelay S and has the function of connect-' ing resource of alternating current B with "relay at thecompletion of a message to efi'ect release of the selector. The letter R indicates the receiving magnet of the teletyper apparatus.

- If upon release of the rotated dial D selector impulses are sent to the automatic exchange by the oscillating movement of the contact d over the relay S. and the conduit L. the

operating magnet H. at such exchange is intermittently excited corresponding to the selector impulses through the medium of the contact Z of the receiving relay E The armature 72. of the magnet H then starts the selector consisting of five rows of contacts (71, k, Z, m) and contact brushes. Assuming that three impulses have been dispatched, the brushes of the selector set themselves on the contacts 3. In the manner usual in automatic selectors the'connecting through relay P is instantaneously excited across the row of contacts n and the C-conductors every time one of the contacts 1 to 3 is touched. Since this relay P is designed as slow-acting relay,

it only responds when the brush stops on the contact selected.

If the line selected was found to be engaged the relay could not respond, since the connecting through relay of the occupied selector would be connected in parallel to the newly incoming relay, so that in consequence of the dividing of the current such a weak current only is available for each relay, that the armature can be maintained in the attracted position, but cannot be pulled up from the position of rest.

The connecting through relay P now connects the four lines a, b, d, e of the selecting stations to the brushes 2', is, Z, m by closing its contacts P a, P 6, Rd and P e. Since the brushes rest upon the contacts 3 and these are in their turn connected to the multiplex lines of the subscriber 3, the transmission of messages may commence without the telegraph impulses now sent over the line, which are of the same kind as the selector impulses, affecting the selectors. This is attained by the relay Q being excited across the closed contact p, f, lines o and c and the relay Q through the winding of the relay F" whereby its contacts 9 and g disconnect the switching magnets H and H of the selectors 1 and 3 from the lines a, b of the subscribers connected at the time.

When the communication has come to an end, the double pole switch A, which may be in the form of a key, is temporarily reversed by one of the subscribers, whereupon the sending relay S is disconnected from the sending and selector contacts and is connected with the source of alternating current B. The alternating current thus sent out has a frequency different from that of the telegra h fre uencyand brings into action, over t e sen ing relay S conductor L and receiving relay E the resonance relay W located in the automatic exchange; the relay W is permanently connected in these lines and is preferably connected through a condenser C in known manner. The relay W thereupon closes, through its armature 'w a circuit for the releasing magnet M which, upon attracting its armature, releases the latching element which holds the selector. The latter then returns to its initial positionunder the infiuenceof a spring; the relays W and P are thus deenergized and the operating magnet H is again connected to the conductors a, I; through g so that the mechanism is again in its original position.

Fig. 2 illustrates diagrammatically a relay, in which the resetting device of the loaded selectors is released by the application of the false position of rest. In this figure W is the winding of a telegraph receiving relay with the working contact a and the idle contact 1'. Both contacts are connected to a pole each of a battery B, the centre of which is grounded.

The armatureof the relay is alternately pulled against one or the other of the contacts by telegraphic impulses, so that a current of alternating direction is closed in well known manner. The working contact upon which rests the relay during the false idle position is bridged by'the winding V of a slow-acting relay. The slow-acting relay whose contacts, not shown, control in 'well known manner a pre-selector and the tripping device of further selectors, is thus short-circuited in the false idle position of the receiving relay W. \Vhen the receiving relay is excited its armature is pulled against the true idle contact 1", whereby the slow-acting relay is connected to the battery B and excited. Its contacts complete the pro-selector circuit and also maintain it closed during the oscillation of the armature between the contacts a'and r due to the retarding action. The subscriber after having finished the preselection may thus continue to select with his dial apparatus and then telegraph. When the transmission is fin shed and the subscriber sends the clearing impulse over the line. for instance by switching off his inotor, the armature of the relay W is finally and for a considerable time pulled against the-contact a into the false position of rest. so that by the dropping oif of the slow-acting relay contacts the selectors are reset into the initial position and the connection is broken.

Various modifications and changes may be made without departing from the spirit and the scope of the invention, and I desire, therefore, tha only such limitations shall be placed thereon as are imposed by the prior art.

I claim as my invention:

1. A telegraph or teletyper system comprising a plurality of subscriber stations, lines for transmitting the telegraphic mes sages, one or more exchanges, automatic selectors at each of said exchanges for connecting said stations selectively, means located at the subscriber stat ons and operative to control the said selectors over the said telegraphic lines', and devices at each of said exchanges for releasing the said selectors at the end of a communication. said devices being operable by current of a frequency difierent from that of the telegraph currents.

2. A telegraph or teletyper system comprising a plurality of subscriber stations, lines for transmitting the telegraphic messages, one or more exchanges, automatic selectors at each of said exchanges for connecting said stations selectively, means located at the subnance relay responsive at the frequency of an alternating current transmitted at the end of the communication.

3. A telegraphic or teletyper system comprisin a plurality of subscriber stations, ines or transmitting the telegraphic messages, one or more exchanges, automatic selectors at each of said exchanges for connect- 5 ing said stations selectively, means located at the subscriber stations and opera ive to control the said selectors over the said telegraphic lines, and devices at each of said exchanges for releasing the said selectors at the end of a communication, said devices including a resonance relay responsive at the frequency of an alternating current transmitted at the end of the communication, said resonance relay being permanently connected to said telegraphic lines.

4 A telegraph or teletyper system comprising a plurality of subscriber stations, lines for transmitting the telegraphic messages, one or more exchanges, automatic selectors at each of said exchanges for connecting said stations selectively, means located at the subscriber stations and operative to control the said selectors over the said telegraphic lines, and devices at each of said exchanges for releasing the said selectors at the end of a communication, said devices being operable by a current of the same nature as that of the telegraphic impulses but of duration different from that of said impulses.

5. A telegraph or teletyper system comprising a plurality of subscriber stations, lines for transmitting the telegraphic messages, one or more exchanges, automatic selectors at each of said exchanges for connecting said stations selectively, means located at the subscriber stations and operative to control the said selectors over the said telegraphic lines, devices at each of said exchanges for releasing the said selectors at the end of a communication, and a relay forming part of the telegraphing circuit and having a contact movable between-a false idle position and a true idle position occupied during the operation of the system, said devices being controlled by the contact of said relay in such manner, that the release of said devicesis effected upon switching such contact from the true idle position to the false idle position.

6. A telegraph or teletyper system comprising a plurality of subscriber stations,

lectors at each of said exchanges for connecting said stations selectively, means located at the subscriber stations and operative to control the said selectors over the said tele' graphic lines, devices at each of said exchanges for releasing the said selectors at the end of a communication, a polarized relay forming part of the telegraphing circuit, and a slow-acting relay having a winding bridg ing the contact of the olarized relay, said devices being controlle by said slow-acting relay.

7 A telegraph or telety or system comprising a plurality of subscri er stations, lines .for transmitting the telegraphic messages,

one or more exchanges, automatic selectors at each of said exchanges for connecting said stations selectively,--means located at the subscriber stations and operative to control the said selectors over the said telegraphic lines, devices at each of said exchanges for releasing'the said selectors at the end of a communication, and switching mechanism automatically cut in at the termination of a communication at a subscriber station, said devices being controlled by said mechanism.

8. A telegraph or telety ersystem comprising a plurality of subscri r stations, lines for transmitting the telegraphic messages, one or more exchanges, automatic selectors at each of said exchanges for connecting said .stations selectively, means located at the subscriber stations and operative to control the said selectors over the said telegraphic lines, devices at each of said exchanges for releasing the said selectors at the end of a communication, and automatic switching mechanism in said subscriber stations adapted to be cut in when the teletyper apparatus is at rest, said devices being controlled by said mechanism.

In testimony whereof I afiix my signature.

AUGUST J IPP;

Images