DE126081C - - Google Patents

Description

IMPERIAL

PATENT OFFICE.

PATENT DOCUMENT

M 126081 CLASS 21 a J

Automatic telephone switch.

Patented in the German Empire on December 15, 1898.

In the case of the so far known automatic telephone switch is on the Mediation office for each participant a special apparatus available, "which one." directing the participant concerned with the direction of another participant directly can be brought into telephone connection. This connection set remains for the entire duration of the connection in the position given to him and only returns to his starting position after the conversation has ended in which it is ready for a new connection. With a number of 10,000 participants there should be 10,000 connection sets on the central office, each of which is separate can connect to any of the 10000 lines. Such a system would appear to be practically impracticable be. ■

However, as can be seen from the American patent specification 556007, one has sought to avoid these practical difficulties by using the communication apparatus can be restricted to a smaller number of lines, for example 250. At a If there is a larger number of participants, there must then be several for each participant Connection apparatus can be provided, as well as a device to connect with at will to be able to connect to one or the other connection apparatus. Is the If the number of participants is 10,000, each participant should have 40 communication devices so that the total number of apparatuses would rise to 400,000. These too Furniture should therefore practically not be usable.

According to the present invention, the number of connecting devices required is now considerably reduced by the fact that the lines of subscribers at the mediation office are combined into groups, and that there is a single one for each group Electromagnetically active "work" is provided, which is carried out by each line this group by a number of current surges of the same or the opposite Direction can be driven in such a way that it can be driven by means of a connecting device (each Group has as many connection devices as there are groups) connecting the calling line with the line to be called, whereupon the "work" returns to its rest position returns and is ready for a new call from any other line in this group. The connection of the calling Line with the "work" is effected by a switch, whichever one for each line line, and which one through one of the calling Participants sent electricity is switched so that the line of the calling Participant is connected with the "work" of the group in question. Sent by another party from the calling party Current surges then become the connection device in question by means of the work put into action.

The connecting devices, of which, as mentioned above, for each group of Line lines as many as there are groups, each consist of two independent of mutually movable, permanently electrically connected contact devices,

one of which (hereinafter referred to as the "seeker") has the task with the two Wires of the to be called. The participant's connection while the other (in Hereinafter referred to as "connector") the connection with the two wires of the calling subscriber causes. They are all connectors of a line group on the one mentioned below Connector boards of this group collected while the related searchers on the Finder boards of the individual groups of lines are distributed, so that there is always a pair whose connector is on the caller's connector board, but whose seeker is is active on the finder board of the line to be called. It gets the connection in the Art manages that the seeker of that group in which the leadership of the person to be called Participant lies, by means of one of the calling participant by a number switching device activated by current surges in one direction or the other is pushed in front of the wires of the desired cable, whereupon, if the desired one Line is free, the connector is automatically pushed in front of the calling line and with it this is connected.

The »plant« provided for each group of line lines consists of a main distributor, a main selector, a working device and a device for returning of the work in the rest position.

The main distributor, equipped with rotating contact arms, is used by each participant posted Stromstofs respectively. for each group of impulses by one division and. has the task of calling Line one after the other with the different parts of the main selector and to connect the working device. The main selector is used for that connection device to select which one is to be considered for the establishment of the connection desired by the calling party comes.

The working device has the destination sent by the calling party To transmit current surges in local currents, through which the selected connection device so put into action that the desired connection is established.

The last part of the work has the task of after making the connection or Establishing the fact that this connection cannot be established at the moment, return the main distributor and selector to the rest position.

The finders and connectors of each group work with one finder board and one Connector board on which for each ^ subscriber line of the group concerned two contacts connected to the line wires of the respective subscriber line or Wires as well as a special working wire are available. In front of these wires, in rows are arranged on top of each other, contact arms of the viewfinder bezw. Connector by moving the viewfinder accordingly respectively Connector passed as a whole. To speed up the establishment of the connections, every seeker exists respectively. Connector from a sliding frame or frame, which is shared with several sets of contact arms moving, usually at rest, in this frame is provided, each of which only moves over a limited number of contact wires and each of them can be released at will, so that by suitable choice and release of the one to be used Set of contact arms each seeker respectively. Connector with only a small shift of the frame as a whole with the respectively to be called. calling subscriber line can be connected.

The search board is used when a line line of the group concerned is to be called while the connector board is in use if the call comes from a line of the group in question.

In order to be able to put the work into action in the required manner, von Various types of current impulses can be sent to the participant. When using of loop lines and the arrangement of a central battery at the switching office three types of surge can be sent. The current can first be sent through the one wire, which is grounded without resistance on the participant's station; furthermore, the Current can be sent through the other wire, which is grounded without resistance, and Finally, the current can be sent through both wires, which are connected in series are without any resistance being inserted between them, and without that they are grounded at the subscriber station. The switchboard battery only needs be grounded with their center.

In order to be able to send the necessary surges in the right way, is on Each subscriber station a power transmitter is provided, which essentially consists of a Number of single- or multi-armed, connected in a certain way with the line lines, partly adjustable contact pieces or strips, over which a contact brush is carried away in sequence. When the contact brush at the first contact meets, such a current becomes the

sent communication office that the switch located there comes into action and the Line line of the calling subscriber with the plant of the group, which the calling party Participant is heard, connected.

Strikes the contact brush of the fuel transmitter as it moves forward on the second and third contact pieces, current impulses are sent to the office, which put the chief distributor and the chief selector into action in such a way as to establish that connecting device is selected, which is its connector on the connector board of the calling line and its finder on the Has the finder board of the line to be called.

With the further movement of the contact brush over the contact pieces of the current transmitter such bursts of electricity are sent out that the seeker communicates that sentence of contact arms, which can reach the line to be called fastest, with the same is associated.

When the contact brush has reached the end of its path, the desired connection is established, or it can be ascertained by listening on the telephone on the calling station that the required line is busy. There will be all of them at once Parts of the work returned to their idle position, so that the same for a new call any participant in this line-group becomes available.

On the accompanying drawings, the distribution of the connection is in Fig. Ι schematically Lingsvorrichtungen shown on the switching boards of the switching office, with two of the lines are shown in telephonic communication with each other. The ones that belong together Figures 2a and 2b show schematically the electrical connections of one of the sets the works of the switching office with a connecting device. Fig. 3 a, 3 b and 3 c show the changes occurring one after the other when driving the mentioned works electrical connections. Fig. 4 shows schematically in a perspective representation a part the connecting boards of two groups of lines with their connecting devices omitting the electromagnetic parts. Figs. 5 to 7 show vertically Longitudinal section, the power transmitter in horizontal section and in vertical cross section; Fig. 8 schematically shows the circuit of this device; 9, 10 and 11 show in Front view, vertical section and top view of an electromagnetic switch. Fig. 12 and 13 show in Ober- respectively. Side view the main selector omitting various Electromagnets. Figure 14 shows the main manifold in top view; Fig. 15 is a Top view of the distributor used to return the main distributor to the rest position. Figure 16 is a top view of the manifold through which the main selector selected connection device is influenced. Fig. 17 shows a part this distributor in side view; Figures 18 and 19 show in front view and in cross-section a connector board. "Fig. 20 shows in side view, partly in section the screw drive mechanism of the seeker of a connecting device; 21 shows, in a top view, the escapement which regulates the screw; Fig. 22 shows, on a larger scale, a similar view; Fig. 23 shows in a top view, partly in section a device for regulating a contact arm selector. Fig. 24 and 25 show the selector in two different positions in cross section. Fig. 26 is a corresponding vertical section through the selector. Fig. 27 shows a top view the sets of contact arms belonging to the connector through which the connection is established with the calling line. 28 shows a side view of a Part of this connector with two sets of contact arms, one of which is set is in working position. 29 shows the device for triggering in a side view the drive screw and the device for returning said connector to the Rest position.

In Fig. 1 a telephone system is shown schematically with six groups, each of which comprises seven subscriber lines. Each group is provided with a connector board ^la , II «, III ^a . . . VI ^a and a finder board P, II * ... VP provided. The wires of each line in a group appear on both boards, and there is a special work wire for each line on each board.

The connectors are represented by rhombuses i ^a , 2 ^a , 3 ^a , 4 ^a , 5 ^a , 6 ^a and the viewfinders by rectangles i ^b , 2 ^b , 3 ^δ , 4 *, 5 ^δ , 6 ^b . For the sake of simplicity, it is assumed that each connector and each finder has only a single set of contact arms which make contact with the line and work wires. In Fig. 1 only the contact arms for the lines are shown.

The contact arms of each connector are each with the corresponding arms of the associated one Electrically connected in the following way:

The arms of ι " group I with the arms of \ ^b group I;

the arms of 2 "Group I with the arms of i ^b Group II;

the arms of 3 "group I with the arms of i ^b group III and so on.

The arms of i ^fl group II with the arms of 2, ^b group I;

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the arms of i ^a group II with the arms of 2 ^b group II;

the arms of 3 ** group II with the arms from 2 * group HI and so on.

Of the line lines L ¹ Z- ² , those which are in telephone connection with one another are indicated by an asterisk. It turns out that a calling line from group I for a telephone conversation is connected to a called line from group V by the fact that the finder \ ^{b of} the finder board V * is in front of the line wires L ¹ L? is pushed and brought into connection with them, while the associated connector 5 ^{s of} the connector board I "is brought in front of the calling line and connected to the same.

In Fig. Ι neither the working arms are shown, nor the lines belonging to them. It should be noted, however, that every theorem of Arms still contains a third arm, which makes contact with the working wires, and that the working arms of the corresponding parts of the connecting device by the following described power lines and parts are electrically connected to each other.

In order to make the delivery of erroneous combinations of current surges impossible, a current transmitter, which is shown in FIGS. 5 to 8, is used on each subscriber station, as stated above. This device consists of fixed and movable contacts, as well as a double brush 164, 165, which can be moved in guides 163. Six vertically displaceable toothed racks 141, 142, 143, 144, 145, 146 can be lifted with the aid of a handle and locked by locking pins 151, which sit on a horizontal slide rail 150. Five of these racks have panels 141 ^, 142 ", 143 ^, 145 ^, 146a ^, each of which has contact pieces and a number of numbers. Depending on the height to which each rack is raised, one or the other other of the contact pieces or one or the other part of the same are brought into the path of the contact brush 164. The rack 144 is provided with two contact springs 152 and 153 which, depending on the setting of the rack, are connected to the two fixed contact pieces 154, 155 or to the contact pieces 155 are brought into contact 156;. it also bears a slider 157 with two adjacent cutouts which ^s are twice the number series of the panel 143 on the front side of the housing is in the path of the brush has a horizontal conductive track 158165 attached, which is interrupted with respect to the attached to the racks 145 and 146 contact pieces 187, 188, 189, 190 and 191, 192, 193, 194. The front wall

of the housing. has a horizontal slot 159 for the passage of the handle 160 of the double contact brush, a second slot for the handle 162 of the slide 150 and five openings 141 *, 142 *, 143 *, 145 *, 146 *, which are opposite the rows of numbers corresponding number plates are located (Fig. 6 and 7). Depending on the setting of the rack 144, one or the other opening of its slide 157 meets one or the other half of the opening 143 *, so that the row of numbers opposite the other half is covered. The double brush 164, 165 is usually pulled to the right by a weight or some other suitable means so that the block carrying the brush presses the spring 166 against the spring 167 (FIG. 5). If the brush is at the other end of its path, it presses the spring 168 against the spring 169 and is held back in this position by a pawl 170 that falls. A block 171 is guided on the slide rail 150, which is displaceable by means of a handle 162 and is limited in its movement by a stop 174. If this handle is moved to the right, the block 171 alone moves first, which brings the resilient contact 172 into contact with the contact 173 ^{by means of a protruding pin 171 s.} As soon as the block hits the stop 174, it takes the slide rail 150 with it, the locking pins 151 being brought into engagement with the racks.

At the same time, a pin 17 or ³ attached to the rail 150 hits the upper arm of the pawl 170 so that the contact brush 164, 165 can be released and returned to its normal position by the aforementioned weight. So that the teeth of the racks can fall behind the pins 151 when they are lifted, the latter are fastened on springs so that they can be pushed back.

The contacts carried by the panel 141 ^ consist of a solid conductive rail 180 and a comb-shaped plate 184 with four (or more) contact arms, the length of which is so dimensioned that, depending on the position of the rack 141, one or more of these contact arms lie in the area of the brush 164. The panel 142 ^s carries massive contact rails 181, 182 and between these a comb-shaped plate 185 with three (or more) contact arms of different lengths, so that one or more arms lie in the area of the brush 164 depending on the position of the rack 142. The plate 143 ^ carries a comb-shaped plate 186 with five (or more

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reren) Confact arms, as well as a massive rail 183. The massive rails 180, 181, 182, 183 must be at least long enough that they can be brought into the area of the brush 164 with each of the arms of the comb-shaped plate at the same time. The table 145 ^ bears a vertical row of contacts 187, 188, 189, 190, which are separated from one another by spaces which are narrower than the width of the brush 164 and whose position in relation to the teeth of the rack 145 is such that it contributes Adjustment of the rack, two of the contacts are always in the area of the brush 164, so that they are brought into contact with one another by the brush as it passes by. The panel 146 ^a carries a similar series of contacts 191, 192, 193 and 194 as well as a solid contact rail 195.

As can be seen from FIG. 8, L ^{1 of} the two line lines L ¹ L ^{2 of} the subscriber station is connected to the contact plate 155 by wires 300, 301 and L ^{2 is} connected to each of the two contact plates 154, 156 by wire 302. The contact rails 181, 182, 183 are connected to the contact spring 153 by the wire 303, and the comb-shaped contact pieces 184, 185, 186 are connected by 304 to the contact spring 152, so that the various connections of the line lines L ¹ and L ² with the contact pieces 181 , 182, 183 and 184, 185, 186 depend on the position of the rack 144. On the other hand, the connections of the small contact pieces 187, 188, 1895, 190 and 191, 192, 193, 194 and 195 cannot be reversed because of the following arrangement. The contacts 188, 192 and 195 are through 317 resp. 316 resp. 315 is connected to wire 314, which is connected by line 300 to line line L ¹ . The contact pieces 189 and 193 are respectively through 308. 307 connected to line L ² via 302. The contacts 187, 190, 191 and 194 are connected by 306 on the one hand to the two parts of the contact bar 158 and on the other hand to the earth line 318. Line line L ¹ is usually grounded through 300, 166, 167, 313, 201, 312, alarm 199, 322, 200, 310, 320, high resistance 196, 320, galvanometer 197, 319 and 318. But as soon as the brush is set in motion, the contact between 166 and 167 is interrupted and the line L ¹ is isolated. When the block of the brush brings the two contact springs 168, 169 into contact with one another, and when the telephone receiver is removed from its hook, the line L ² via the telephone 198, the high resistance 196 and the galvanometer 197 is grounded. Of the two contact springs 172, 173, which are shown in the upper part of FIG. 8, 173 is permanently earthed via 305, 158, 306 and 318, while 172 is connected via 303 to the contact rails 181, 182, 183 so that it how this can be connected to one or the other line cable.

The transmitter, the receiver and the bell of the participant have the usual arrangement, only the line L ^{2 is} switched on or isolated by the spring 200, which is controlled by the hook switch 201 which switches the microphone battery on or off.

The power transmitter is put into action as follows:

Usually the line L ^{2 is} insulated and the line L ^{1 is} connected to the ground by a resistance of 1000 to 2000 ohms. As soon as the participant, after having adjusted the rack, begins to move the brush 164, 165, the line L ^{1 is} also insulated. The following effects occur in sequence:

1. As soon as the brush comes into contact with the two contacts 195 and 158, the line L ^{1 is} conductively connected to the ground, and an invariable current is sent out, which activates the switch of the line and thus the connection of the line with who produces "works". Line L ¹ is isolated again when the brush leaves contact 195.

2. Depending on the position of the racks 146 and 145 (depending on whether the brush 164 strokes the contact pairs 191, 192 or 192, 193 or 193, 194 or 187, 188 or 188, 189 or 89, 190), two different types of current impulses are emitted by connecting the line L ^{1 to} earth without resistance or by connecting the lines L ¹ L ² one behind the other without resistance and without earth fault or by connecting the line L ² to the earth without resistance. These surges reach the main selector and are intended to select the viewfinder that is suitable for the desired connection. Both lines are then insulated again.

3. Depending on the setting of the rack 144, either each of the rails 181, 182, 183 is connected to the line L ¹ and the comb-shaped contacts 184, 185, 186 are connected to the line L ² , or vice versa. This makes it possible to send the following surge currents described under a) and b):

a) The line L ¹ is connected once to earth, the line L ^2, however, several times, depending on the position which the rack 143 assumes; the line L ¹ is grounded a second time and the line L ² again as many times as this is due to the position

the rack 142 is conditional; the line L ¹ is grounded a third time and the line Z- ² as often as this corresponds to the position of the tooth length 141 until the brush is finally locked by the pawl 170.

b) The different current surges can also be sent in reverse through the line lines L ¹ L ' ² .

All the current surges mentioned under 3. reach the relay, which the working device forms, and are there unconverted into local currents. The local currents that cause the brush 164 to go over the rails 183, 182, 181, 180 correspond to this determined to influence the distributor of the selected seeker, so that that distributor the different parts of the seeker in turn, the rest, going away the brush 164 via the comb-shaped contact plates to the corresponding current surges Use. In fact, the current surges corresponding to the contact plate 186 the displacement of the viewfinder is regulated via the contact wires of the viewfinder board while through the current surges of the contact plates 185 and 184 for the desired Connection expedient set of contact arms of the viewfinder is selected.

The combination of current impulses described under a) or under b) is used, depending on one or the other of the compiled below Wants to use "twin finder".

In the following it will be assumed that the line L ^{1 is} connected to the rails 181, 182, 183 and the line L ^{2 is} connected to the comb-shaped contact pieces 184, 185, 186.

As soon as the double brush 164, 165 has reached the end of its stroke, all the current impulses required to influence the switch-on device, the main selector and the working device are sent, and the calling participant only needs to listen to the earpiece for the characteristic noise indicating the presence of a line becomes audible or not. In the former case the called line is busy, in the latter case it is free. In any case, the calling subscriber now moves the handle 162 of the slide 150 to the right, whereby first the two springs 172, 173 are pressed against each other and a closing current is sent, similar to that when the brush moves over the rails 181, 182, 183 ( ie under the condition that the line L ^{1 is} earthed). This electricity also reaches the finder distributor. With the further movement of the handle 162, the brush is released and returned to its initial position, and the toothed racks, which return to their initial position, are also released.

In order to avoid too rapid or uneven displacement of the brush, which when moving the brush by hand. can easily occur and cause If there is an inadequate transmission of the current surges, the forward movement of the brush can cause it a suitable device can be controlled, for example by means of a wind blade, the is set in rotation by a roller over which the string of the weight runs, or by a cataract associated with the cord.

For every position of a toothed rack, a certain number visible. To invoke a particular participant it is only necessary to move the racks in such a way that the numbers appearing at the openings form the number of that participant, and then the brush at one end of their path move after the other. The recipient at the calling station then shows whether the called line is free or not, and the Schlufsstromstofs then completes the work serving to establish the connection or brings all parts to their rest position.

Example of the use of the electricity transmitter.

Since all of these effects are more conveniently understood with the aid of an example, let Assume that subscriber 23423 is to be called.

Since in the present device, the lines that make up the entire telephone network of a Form localities, divided into several large groups, and there the lines of each Group are arranged on a finder board corresponding to this group, namely on this in groups in such a way that five wires line up one after the other at the height of the board follow, then an empty space is left and then five lines of wires follow again and so on, so it is clear that the position of a line in the whole arrangement is perfectly determined, if only her search board, furthermore the group of five lines to which she belongs on this board, and finally the place which it occupies in this group of five lines, exactly are determined.

Five numbers are now chosen as the number of a certain line, of which, like further explained, the last two (from the left) the finder board, the third the position in the Group of five lines of the finder board, the first two (from left) the group itself of denote five lines. Such a procedure for numbering the lines is evident

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well founded. Since two lines do not have the same material situation in the Centrale two lines will never get the same number.

According to this numbering, in the example given, number 23423 results,

1. that the line in question is attached to the finder board, which is marked with the numbers 3 and 2 is indicated;

2. that it belongs to the group of five lines to which it belongs on this board Takes place which is designated by 4;

3. That it finally belongs to that group of five lines which are marked with the numbers 3 and 2 is indicated.

Like the last two numbers the finder board, the third the position of the line in hers Group of five lines, the first two precisely designating the group itself, shall now be explained will. Here, however, comes the entire facility of the electricity transmitter on the one hand, of the main selector and the viewfinder on the other hand.

ι. From the main selector of a line group leads to the finder, which one of these Line group in front of a certain Suc.herboard corresponds to a single selector circuit. So a single designation can be used for both this selector circuit or the searcher, to which it leads, or the search board itself, in front of which the searcher stands, exactly describe. But in order to choose and close a certain selector circuit, two consecutive current surges are required. Depending on namely these bumps one or the other of the three electromagnets of the first respectively. second limbs of the If you want to put the main selector into action, they will be from the electricity transmitter in the one Position of the racks 146 and 145 sent, in which the numbers 1 respectively. 2, 3 appear in the opening 146 * (or 145 *). Each of these surges can therefore be designated by the number corresponding to it. As a result, the combination of two surges in this selector circuit asleep, or this selector circuit itself, or the searcher to which it leads, or also the search board, in front of which this seeker stands, with the numbers of these two Current surges are called. This is the name given to the last two in the example given Pay that the search board is used which is connected to the calling party if that party has the Racks 146 respectively. 145 so that the numbers 3 resp. 2 in openings 146 ^ respectively 145 * appear.

2. There on the finder board the lines, as said above, in small groups of five each Lines are arranged so in each group there are five digits. The first digit with o is the the second with 1, the fifth with 4, these designations correspond to the numbers, indicated in the first (left) row of the slide 143 "of the" Stromstofssender " are. Since in the rest position of the seeker, all sets of contact arms are empty Face gaps, and there one, two. . . five power surges are required to this seeker and his sets of contact arms by one or two. . . five steps ahead of the first second . . . fifth digit of the various groups of five lines as a whole too slide, and since this number of current surges sent from the comb-shaped plate 186 If the numbers 0,1 ... 4 appear in the opening 143 *, it follows from this, that if the rack 143 is set so that a certain number in the opening 143 * appears, - in the example given, number 4, - the seeker and his sentences of Contact arms as a whole to the appropriate - in the selected examples the 4 -f ι = 5th place to be pushed. The numbers 5 to 9 of the second (right) row of the slide 143 "serve to indicate the lines, which have equal places on the twin search board.

3. Since finally everyone with the total displacement of the viewfinder and his contact arms Set of contact arms only moves in front of a single group of five lines, so can have the same designation both this set of contact arms and the one facing it Identify the group of five lines precisely. A certain set of contact arms is only supported by a certain, his own combination of electrical surges which activate the contact arm selector, released for contact formation, and so this set of contact arms can through him corresponding combination are designated. Since this combination consists of two rows of Current surges and identified by the number of current surges in each row is, and since this number of streams corresponds to the numbers which are in the openings 142 * respectively 141 * by pulling up the racks 142 respectively 141 are made visible, so can both the combination and the set of contact arms as well as the group of five lines opposite to it determined with these two numbers are designated. In the example given it will be said that the The line in question belongs to a group of five lines, in front of which the proposition of Contact arms moved during the total displacement of the viewfinder, which with three current surges in the first limb, with two current surges in the second limb of the Conlactarmselferelers is released. . And there that

Finder board and the place in the group of five lines have already been determined, that's it Line itself completely determined.

In order to call the participant 23423, the calling participant will set the racks of his electricity transmitter in the following way: rod 141 until number 2 appears at the opening; Rod 142 up to number 3;, rod 143, until numbers 4 and 9 appear together at opening 143 *; then rod 144 so that its slider covers the number g on rod 143; Finally, rods 145 and 146 up to numbers 2 and 3. During this entire preparation the "work" remains completely unaffected, and only then is it influenced by the calling participant when he moves the brush 164 by means of the handle 160. But then, since batteries b ⁵ , c and e (Fig. 2a) come into contact with the lines one after the other on the central station, the current surges follow one another in the following series:

1. When the brush 164, 165 passes the rail 195 and the first part of the contact rail 158, line L ^{1 is} grounded.

2. When the brush passes the two contacts 193, 194 together, line L ^{2 is} grounded.

3. When the brush passes the two contacts 188, 189 come together

'both lines connected without resistance. Since the rack 144 is set so that the opening of its slide covers the number 9 of the second column, the solid rails are connected to the line L ¹ , the comb-shaped contacts to the line L ² . Accordingly, will

4. when the brush passes the rail 183, line L ¹ is earthed once,

5. when the brush passes the comb 186 line L ' ² grounded five times,

6. When the brush passes the rail 182, line L ¹ is earthed once,

7. when the brush passes the comb 185, line L ' ² earthed three times,

8. when the brush passes rail 181, line L ¹ grounded once,

9. As the brush passes comb 184, line L ' ² grounded twice.

Finally, line L ¹ is grounded again when the calling subscriber, after listening on the telephone, presses the handle 162 and brings the springs 172, 173 into contact with one another.

Effect of electricity transmissions.

First electricity shipment. The effect of these surges in the central station is as follows:

As can be seen from Fig. 2a, line L ^{1 is} in the rest position through spring α ⁴ , coil of electromagnet A, rest contact and armature a ⁹ with the contact b ^{l of} the main distributor B and by means of the double brush of this main distributor with the earthed battery b ⁵ connected.

The electromagnet A and the electromagnetic changeover switch A ¹ constitute the above-mentioned changeover switch provided for each line. A is an ordinary electromagnet with working contact.

In Figs. 9 to 11 is. the electromagnetic switch A ¹ , which receives the first Stromstofs of the Stromstofssender, shown in side view, section and top view. The armature a ^{12 of} the electromagnet carries a cross bar a ¹³ made of insulating material, which acts on contact springs a ^l d ² a ³ cft a ⁵ a ⁷ a ⁸ (Fig. 2a). In the rest position, this transverse rail a ^{13 separates} the upper springs a ¹ a ^z a ° a ⁷ from the contact rings a ¹⁶ , with which the lower springs are in contact. When the electromagnet is excited, the lower springs α ² α ⁴ a ^{s are} removed from the contact rings, while the upper springs come into contact with them. All springs and rings are isolated from one another and independent of one another. The armature a ¹ ' ² itself forms contact with an insulated contact piece α ^{17 in the} manner of a relay. Depending on requirements, a larger or smaller number of contact springs and contact rings can be arranged.

The main distributor B (Figs. 2a and 14) has three equal sectors IB, HB, IHB and three equally spaced, insulated double brushes b, which are simultaneously passed intermittently over the sectors by means of an electromagnet B ^1. Each double brush b is guided over a sector in four paragraphs, which are indicated by the arrows b ¹ b ' ² b ³ & ⁴ , and each sector presents the double brush with pairs of concentrically arranged contact pieces, the two contacts of a pair lie on the same radius. In some cases consecutive contact pieces of the same row are combined into one. Regardless of whether this is the case or not, the contacts of each sector will come into effect in pairs at b ¹ b-b ³ £ ^4. The brush shaft 204 is provided with a ratchet wheel 203 in which a ratchet 202 engages. This is moved in one direction by a spring 205 and in the other direction by the armature lever 206 of the electromagnet B ¹ , so that each of the three brushes b is moved one step further when every excitation of the electromagnet B ^{1 ceases.} A pawl 207 prevents the switching wheel 203 from turning back. The wire L ¹ (FIG. 2a) is usually through the wire 500 !, the spring α ^{4 of} the switch A ¹ ,

the coil A, the rest contact and the armature α ⁹ of A ² , the wire 501 and the brush b ¹ , which are the contact pairs of the sector IB. of the distributor B at b ^l connects with each other, connected to a battery b ⁵ , which is similarly permanently and in readiness connected to all the line lines L ^{1 of} the group. The voltage of this battery ^b is not sufficiently high to energize the electromagnets A, remains switched on in the line, line ¹ to the station of the part of the contractor resistor 1000 to 2000 ohms. However, if this resistor is switched off and the line L ^{1 is} thereby connected directly to the earth, the magnet A attracts its armature α , brings it into contact with the working contact and closes the circuit of the local battery b ⁶ through the electromagnetic coil B ^{1 of} the main distributor - B, the wires 502 and 503 and the coil of the electromagnetic. Multiple changeover solenoids A ¹ . There are now two effects:

1. As soon as the armature of B ^{1 is} attracted, it is in the appropriate position to advance the main distributor B by one division when the exciting current ceases.

2. The multiple changeover magnet A ¹ is put into action and the spring α ⁵ comes into contact with its working contact, the current of the battery f - ^{12 being closed} through the coil A ^{1 by} means of the wires 504, 505, so that the armature and the Contact springs of the solenoid a ¹ independently of the current of the battery b ^(\ which it first moved, are retained in its operative position. the contact spring a ^1, which is connected through the mediation of a small battery a ¹⁰ to ground is through the wire 506 makes contact with the working wire W ^{b of} the calling subscriber, whereby this insulated wire receives the potential of the battery a ¹⁰ , and therefore, as will be explained later, no other subscriber can connect to the line of the calling subscriber Contact spring, a ^{1 of} the multiple switchover magnet Ä ¹ sets the working line W ^a (the calling line) on the connector board of the group with the earth through the wires 507, 508 , 509 and the coil of the commutator magnet A ² , thereby preparing the later connection of the calling party with the called party, if the latter is free, as will be explained later. . The contact spring α ⁴ separates from the line L \ which now comes into contact with the contact spring α ³ through wire 500, whereby the line L ¹ through wire 510 .at b ² \ b ^% £ ⁴ with the long strip of the second Sectors IIB ■ of the main distributor B is connected, while the armature a ^{n of} the switching magnet A ¹ , which touches its' effective contact, the connection between the previously insulated conductor wire. L ² and the long strip of the third sector IHB of the main distributor ' B at b ² b ³ b ⁱ , namely via the wires 511, 512.

II. The contact spring α ⁴ separates' from the line L ¹ (immediately after the battery / ^{12 has been} connected to the coil yonA ¹ by the spring α ⁵ ), the ground circuit of the battery b ^b (by wire 501) is connected the station of the participant interrupted, the coil A is de-energized and its armature α interrupts the circuit of the battery b ⁶ , which was obtained by the coil A ¹ , the wires 503, 502 and the coil B ^{1 of} the main distributor B. As a result, coil B ^{1 is} de-energized, its armature returns, and the main distributor is advanced by one division. As the brush b. of the sector IB has the contact pair b ^l , the common battery b ^s , which is connected by the brush to the lines L ^{1 of} all participants in the same group; was connected, switched off and the current indicators 197 (Fig. 8), which are switched on at the subscriber stations between the resistor and the earth, are de-energized and thereby indicate that the group is common. Main distributor B, main selector D and working apparatus E are in use and therefore no subscriber of this group can call for the moment.

Second power transmission. When the brush 164 passes the two contacts 193, 194 together, line L ^{2 is} grounded. .

When the brushes b of the main distributor B have reached the position b ² when the excitation of the electromagnet B ¹ ceases, the lines L ¹ L ² with the group C of three relays c ¹ c ² c ^{s are} through wires. 513, 514 (by wire 500, the springs ^3, wire 5.10, Contact pair 'of the sector ² IIB _of: Annual General Meeting _r Theiler, and wire 513, what; line Z, ¹ is concerned, by 511, anchor a ¹² Contact λ' b ⁷ ,, wire 512, contact pair b ² , of the sector IHB of the main distributor, and wire 514, which concerns the line L ² ) connected: their known arrangement the production of the three different types of current surges, which in the two-wire in question - and central battery ■ telephone system are possible .. permitted. Two of these relays (c ¹ and c ³ ) are located on both sides of the battery c, the center of which is via the third relay c ² . grounded. is. Depending on the one who called; Participants; A given current transmission has the effect of closing one of the lines L ¹ L ² to earth without resistance, or switching both lines one behind the other without resistance, relays c ¹ c ² or relays c ² c ^B

IO

or the relays C ¹ C ³ energized by the current. The three armatures of the relays c ¹ c ² c ³ are connected to one another and the three working contacts are connected to the battery b ⁶ through the coil B ¹ . The three rest contacts are connected to one terminal of each of the three electromagnets C ¹ , the other terminals of which are closed to earth (by the wire 515 and the pair of contact pieces b ^{2 of} the sector IB of the main distributor B). These three electromagnets C ¹ form the device for moving the first part of the main selector D. This main selector D shown in FIGS. 12 and 13 has nine long contact springs 51, 52, 53, 54, 55, 56, 57, 58, 59, which are attached to a metal piece D ⁰ and can come into contact with nine contact springs 51 ", 52", 53 ", 54", 55 ", 56", 57 ^a , 58 "and 59 ^{a, which are insulated from one another and attached to a support.} This selector has two departments of three bars each D ¹ D ² I) ³ respectively. D * D * D *. Each rod is pulled to the left by a spring and is provided with a tooth 60 which engages with a ^{pawl 61 forming the armature of an electromagnet C 1} (FIG. 13). Three electromagnets C ¹ , only one of which is shown, regulate the rods D ¹ D ² D ³ , and three electromagnets C ² , of which only one is also shown, the rods D ⁴ D ⁵ D ⁶ . Each rod carries three stops d ¹ d ^s d ⁹ of insulating material which, as long as the rod is held back by its tooth 60, rest against three of the contact springs and separate them from their contacts. These stops are arranged so that in each division each of the three rods comes into contact with different contact springs. The arrangement of the stops is different from one another in the two sections. In the first division, the rod D ¹ acts on the springs 51, 52, 53, the rod D ² on the springs 54? 55? 56 ^and the rod D ³ on the springs 57? 58? 59 ^em · B ^e i of the second division ⁴ is the rod D with the springs 51, 54, 57, the rod D ⁵ with the springs 52, 55, 58 and the rod D ⁶ with the springs 53, 56, 59 in engagement . So each spring is held by a rod of the first link and a rod of the second link and can only make contact when these two rods are released from the pawls 61 of the two electromagnets C ¹ C ² , which correspond to these rods. The stops 65 limit the displacement of the rods. In the middle of this main selector, nine selector circuits can be regulated. The return to the rest position is brought about by the electromagnet F ² (FIG. 13), the armature 64 of which carries a transverse rod 62. If one of the rods D ¹ to D ^{e is} triggered, it rests with its pin 63 on the cross rod 62, and when this cross rod together with the armature is attracted by the magnet F ' ² , it brings the rods back into their rest position .

According to the nature of the current surges emitted by the participants, the armatures of two of the relays c ¹ c ² c ^s of group C are moved down, while the third remains at rest. One of the three electromagnets C ¹ , which corresponds to the combination formed by the two depressed armatures, is therefore excited. Here the first part of the main selector D is put into action in a certain manner corresponding to the nature of the emitted fuel. The current which ^{excites this electromagnet C 1} also flows through the coil B ^{1 of} the main distributor B, the armature of which is attracted so that it is in the position to move the brushes of the main distributor forward by a second division as soon as the Armature of the two energized relays of group C return to the rest position and interrupt the circuit of the batteries b ⁽ ' . In the case of the example chosen, where line L ^{2 is} earthed, relays c ² and c ³ of group C are disconnected from the current the central battery c is excited, and accordingly the current of the local battery b ^{R is sent} through the coil of the electromagnet B ¹ and through the right relay of group C, and the corresponding rod of the first part of the main selector is triggered.

Third electricity shipment. When brush 164 passes the two contacts 188 and 189 together the two lines are connected without resistance.

This current broadcast is produced by the calling party in the same way as the previous one, and the receiving apparatus is the same, that is, the main selector; only, since the brushes of the main distributor B are in their third position b ³ , the local current from the relays of group C, according to the type of signal, is directed to the second group of electromagnets C ² , which are similar to ^{magnets C x and} by the brushes, which connect the third contact pair of the sector IB of the distributor B 'at b ^s , are connected to the earth by 516. These electromagnets C ² form the device for regulating the second part of the main selector D. If one of these magnets is excited as a result of a transmission of electricity, it activates the second part of the main selector in the corresponding manner. Since, in the example chosen, the two lines are connected without resistance, the two relays c ¹ and c ^{3 are} energized, and accordingly

/ J- / 7

the current of the local battery b ^{a flows} through the middle of the three relays C ² , which is energized and triggers the corresponding rod of the second part of the main selector.

As a result, since the two parts of the main selector D have been influenced one after the other, the special selector circuit which corresponds to the second and third power transmission of the participant is closed. Each selector circuit influences so-called twin seekers, which will be explained below. Assume that the closed selector circuit is the one which is denoted by d d ' ² d ¹ d ° in FIGS. 2 a and 2 b and is shown in the open state at d.

After completion of the third transmission of electricity, the brushes b of the main distributor move into the fourth position, in which the line lines L ¹ L ^{2 are} connected to the working apparatus E by wires 517, 518 through the contact pairs b * of the second Sector IIB and the third Sector III B .

Fourth electricity shipment. When the brush passes the rail 183, line L ¹ is grounded once.

For the sake of convenience, consider the current surges caused by brush 164 generated on the solid rails 183, 182, 181 become, »distribution currents« that but, which are generated by the brush passing by the combs, "selector currents" called.

These two types of power transmission differ from each other in that one line is grounded for one and the other line is grounded for the other, and accordingly one or the other of the electromagnets E ¹ E ^{2 of} the working apparatus E is caused by the current of the battery e is excited and attracts its anchor. As mentioned above, it depends on the position of the rack 144 of the power transmitter whether the distribution or selection currents are grounded in the event of a ground fault on line L ¹ or line L ² .

In the case of the example chosen, the distribution currents are sent in the event of a ground fault in the line L ¹ and consequently when the electromagnet E \ is excited, but the selection currents in the event of a ground fault in the line L ² and the excitation of the electromagnet E ² .

Since the fourth current broadcast is a distribution current, the armature of the electromagnet E ^{1 is moved} against its working contact. On the one hand, the armatures of the electromagnets E ¹ E ' ^{2 are} connected to one another and through 519 to a metal piece at D ⁰ , which closes the special selection circuit determined in each case by the combination of the electricity consignments No. 2 and 3. On the other hand, the working contact of the electromagnet E ^{1 is} through 520 with a battery e ¹ and by means of the wires 521, 522 of the first contact pair f ^{1 of} the first sector IF ^{4 of} the rest position distributor jp ⁴ , the wire 523 and the coil F ^{s of} the distributor F with the Connected to earth. Conversely, the working contact of E ^{2 is} through 524 with a battery e ² (which has opposite polarity to the battery e ^l ) and through 525, the first contact pair f ^{l of} the first sector IF of the rest position distributor F, 526 and the coil F ~ ^ö des Distributor F ¹ connected to the earth. As soon as the armature of E ¹ touches its working contact, a current flows from the battery e ¹ through the selector circuit dd ² d ^l d °, which has been closed by the main selector D, and through the coil F ^{3 of} the rest position distributor F. Through this two effects are achieved:

i. The polarized double receiver H (or H ¹ H ² , Fig. 2b), which is arranged at the end of the selector circuit under consideration, is activated according to the direction of the current which it receives.

This polarized double receiver H can consist of two simple polarized relays H ¹ H ² , of which one or the other, depending on the direction of the current emitted, is excited. Assuming that the relay H ^{1 is} excited by the currents emitted by the battery e ¹ (which are, for example, the distributor currents), the relay H ² operates according to the selector currents which are supplied ^{by the battery e 2.} The armature h ^l h ' ^{2 of} the two relays H ¹ H ² are also connected to the same battery K ⁶ . The current from the working contact of the relay H ¹ finds, as explained further below, the ground fault through 527, the first contact pair g ^{1 of} the sector IG ^{2 of} the finder distributor G ² (which is assumed to have its brushes in the rest position) 528, 52g, the electromagnet g ^{· 11} , 530, the contact pairs ^{g 1} g ² g ³ g ^l g ^{s of} the fifth sector VG, 531, 532, and the coil G ^{1 of} the distributor G. Conversely, the current from the working contact of H ^{2 takes place} Earth fault through 533, 534, the first contact pair g ^{1 of} the sector IG of the search distributor G, through 535, 536, through the electromagnet g ¹² , 537, the contact pairs g ¹ g ² g ³ g ⁴ g '°, of the sector VG ² des Seeker distributor G ² , 538, and through the coil G ³ of distributor G ² (Fig. 2 b). The first distributor current, therefore, by bringing the brushes of distributor G from g ¹ to g ² , breaks all connections between battery h ³ and coil G ³ of distributor G ² , which in its idle state

position is locked. In the example chosen, the armature h ^{1 of} the polarized relay H ^{1 is} attracted to its working contact.

On the other hand, when the brushes of distributor G have reached position g ' ² , the mechanism which regulates the movements of the viewfinder associated with it is in the position in which it can receive the selector currents from battery h ^3. If the first distributor current had had the opposite direction (ie it would have been achieved by the earth fault of the line L- and the response of the relays E " ² and H ' ² ), the distributor G and the associated seeker would now be blocked and the distributor G ² would have been put into working position.

(. Ι Figure 5) 2. The rest stellungsvertheiler F has two equal Sectoren IF, IIF, and two brushes /, each of which is moved over a Sector in eight paragraphs that by the arrows / ¹ J ^2/3 / * / ^5/6/7/8 are indicated, some of these arrows (f ^1/7/8) arranged on concentric circles of pairs of contact pieces, respectively. In the sector IF there is a pair of contact pieces in the positions f ¹ f ¹ f ⁱ . In the other Sector IIF there are only ⁸ pairs of contact pieces ^{at positions / 1} and f. The drive mechanism for the brushes consists of two oppositely acting pawls 208, 209, which engage in a ratchet wheel 210 of the brush shaft 211 and are connected by a rod 212 to the armature of the electromagnet F ^s , so that the brushes f of the distributor around one Divisions are indexed when the armature is tightened, and by one further division when the armature is returned to its rest position by a spring.

As soon as the current of the battery e ¹ (when the armature of the electromagnet E ^{1 is} attracted) flows through the coil F ^{3 of} the rest position distributor F , the brushes of a rest position distributor move forward by one paragraph, and after the current has stopped by another paragraph, see above that they get into the third position f ³ . From then on, the connection between the battery e ² and the coil F ^{5 of} the distributor F ^ is interrupted, so that the coil F ^h becomes ineffective, and by currents which are later sent by the battery e ² when the latter passes through the resistor of coil e *, which is just as large as that of coil F ^& , which is connected to earth, cannot be influenced.

If conversely (with a different setting of the rack 144) the first distributor current through the earth fault of the line L? had been established, a current would have been sent from the opposite direction through the polarized double receiver //, and the brushes of the at-rest distributor F ¹ would have advanced, while the distributor F would have been rendered insensitive to the currents of the battery e ^1.

Fifth electricity shipment. When the brush of the power transmitter passes the comb 186, the line L ^{2 is} grounded five times.

As a result, selected current surges are sent in that, in the example chosen, the line V ^{2 is} earthed on each of the five teeth of the comb 186 which are brought into the path of the brush 164 (depending on the position of the rack 144). Each time the current of the central battery e flows through the coil of the electromagnet Ji ² , wire 518, contact pair £ ⁴ of Sector III B of the main distributor, wire 512, contact α ¹⁷ , armature a ¹² , wire 511 and line L ² to earth. The armature of this electromagnet E- is attracted to its working contact five times and then released again. The battery e ² finds the earth fault through the resistor e ⁴ on the one hand, through the selector circuit under consideration and the polarized relay H ' ² on the other hand (Fig. 2a and 2b). Since the brushes of the viewfinder distributor G have already reached position g ² , in which connection between the working contacts of the relay H " ² and the electromagnet K, which controls the movement mechanism of the viewfinder, through the contact pair and the brush of the first sector IG and the wires 533, 534, 539 is established, the corresponding local currents of the battery h ^{3 will set} this movement mechanism into action in a corresponding manner.

This way of course depends on the details of the arrangement, but in various ways Kind can be changed without thereby changing anything in the essence of the present system, if only the essential point remains, namely: that every seeker (or connector) consists of two main parts: a sliding frame, which with a number is provided with contact arms and as a whole opposite the finder board (or connector board) can be moved; - and from a selector device (contact arm selector), which, according to the current surges of the calling subscriber, set one or the other set of contact arms from the rest position can bring into the working position. The seeker distributor, on the other hand, is only an accessory to the various parts of the seeker itself and the associated apparatus to connect in turn.

In the device described here as an example, the electromagnet K regulates the amount by means of the current surges sent to it

the displacement of the viewfinder compared to the Finder board. The viewfinder therefore advances five steps from the rest position, what, how further declares one of his sets of contact arms opposite the contact wires of the person to be called Line brings.

Electricity consignments No. 6, 7, 8 and 9.

As the brush passes rail 182, line L ¹ is grounded once.

In order to complete the connection of the seeker with this line, it must now Set of contact arms previously held back in the rest position are put into action; this is the task of the selector currents specified under nos. 7 and 9.

Usually, all sets of contact arms of a viewfinder are through a selector held back; this device or contact arm selector, like the main selector, consists of two independent ones adjustable links, and it is impossible for any set of contact arms to from to move from the rest position to the working position, as long as both members are not on a certain, different positions can be pushed for each set.

The second series of selection currents indicated under no. 7 is intended to set the electromagnet M, which controls the first member, into action with the appropriate number of current surges, while the last series of current surges indicated under no acts in the same way on the electromagnet Ai ¹ which regulates the second member.

The activated distribution currents indicated under No. 6 and No. 8 are intended to move the seeker distributor G from the second position g · ² , in which the working contact of the electromagnet H ^{3 is} connected to the electromagnet K , to the third g ³ , respectively . fourth position to slide g ^l , in which the same Arbeitscontact with the electromagnet M by wire 540 Bezw. connected to the electromagnet Ai ¹ by wire 541.

In the example discussed above, the viewfinder was already five paces away from the Rest position shifted out as a whole; now the set of contact arms, which with three current surges in the first link and two current surges in the second link released is brought into working position and comes into contact with the contact wires of the finder board stretched across from it; as mentioned above, these wires are those of the line to be called.

Seeker Distributor.

The seeker distributor G, which is shown in FIG. 16 in a top view and in FIG. 17 in a side view, has an electromagnet G ¹ with double winding (FIG. 2 b) and is divided into five equal sectors IG, IIG, HIG, IVG, VG divided. Five elle on the same W ^T of each isolirte brushes are mounted and will be moved in six paragraphs, which are indicated by the arrows gi g.2 g% g g i <s G.6 on the Contacte. As with the distributors described above, pairs of insulated contact pieces are provided which are arranged concentrically to one another. Some of the contacts are united with those who follow in the same circle. In the IG and VG sectors, the brush meets contact pieces in all six positions. On the sector IIG there are only in the positions g · ⁴ g ⁵ g ⁶ pairs of contact pieces, and on the sectors III G and IVG only in the positions g · ⁵ and g ⁽ \ On the shaft 215 of the brush g there is a ratchet wheel 214, in which a pawl 213 engages, which is moved in one direction by a spring 216 and in the other direction by the armature lever 217 of the electromagnet G ¹ , so that the distributor brushes g are indexed by one tooth each time the electromagnet a pawl is energized g ^1. 218 prevents backward rotation of the brushes. on the brush shaft (Fig. 17) is a disc 219 mounted from Isolirmaterial which is in accordance with the brush g in five Sectoren divided and is provided with Hubdaumen through which in the In the first four positions of the distributor brushes, the two contact springs g ⁷ g ^s (Fig. 17) are kept in contact with each other, while in the last position of the brushes the two contact springs g® g ¹⁰ are brought into contact with one another. This is achieved in that, for example, the upper side of the disc 219 is provided with elevations 220, each of which corresponds to the first four steps of a brush in terms of its position and angular extent, and which act on the contact spring g ⁷ . Each increase is followed by a depression 22.1, which corresponds to the positions g ^% and g ^{e of} the brushes. The lower side of the disc is provided with depressions which correspond to the first five positions of the brushes and which are followed by elevations 222 which correspond to the sixth position g ⁶ and serve to press the contact spring g ^a against the spring g ^10.

Viewfinder.

The viewfinder described as an example is shown in Figs. Fig. 20 shows it in its rest position, while it is shown in Fig. 26 as it is about a division down, and with the second set of his contact arms with the line and

Contact has formed working wires with which his contact arms come into contact have been. That shown in Fig. 4, 18 urtd "19 The finder and connector board consists of an open frame 66 made of insulating material in which rows of wires are stretched with four equally spaced wires in each row.

The two middle wires (Fig. 19) are the line lines L ¹ L ^{2 of} a subscriber, while the two outer wires are the working wires of which W ^{a is used} when calling, while W ^{b is} used when calling the line. Five such rows of wires are arranged at regular intervals one above the other and the five rows of wires belonging to a set are separated from the next set by a space. The connectors are located on one side of the board and the viewfinders on the other side of the same.

The viewfinder consists of a frame 67, which in guides 68 (Fig. 23) vertical can be moved. On this stand there are so many sets of Arranged contact arms, available as sets of five rows of wires on the finder board are. The sets of these contact arms are separated from each other by a space, which is equal to the height of this set of five rows of wires and the one following these Space is. Each set of these contact arms consists of three arms, which are horizontal can be moved across the rows of wires in order to form contact with the lines and working wires in front of them can.

By shifting the frame vertically, the contact arms are shifted in steps until the one set of contact arms is at the level of those wires on the finder board which are to be called Line match. In the highest case, five intermittent movements are required to to bring before a given line that set of contact arms which corresponds to the five Corresponds to rows of wires in which that line is located.

The viewfinder can be moved up or down. In the arrangement shown in FIGS. 20 to 26, the displacement takes place along a screw spindle 69 with a steep downward gradient and is regulated by an inhibition which is under the influence of an electromagnet K. With a complete oscillation of the armature, the viewfinder is moved downwards by the distance between two successive rows of wires on the viewfinder board.

The vertical screw 69 is stored in the fixed frame. The displaceable frame 67 is fastened to the displaceable nut 70 of this screw (FIG. 26). The screw 69 carries a ratchet wheel 71 which is provided on its underside with three projections 72 which protrude equally from one another (FIG. 21). These projections come into engagement alternately with the pawls 73 of the escapement anchor 74, which is held by a spring 75 in the rest position shown in FIGS. 21 and 22 and shown in full lines. As soon as the electromagnet K is excited, it brings the armature into the position shown in FIG. 22, shown in dotted lines. The number of projections 72 and the pitch of the screw 69 is chosen so that with a complete back and forth movement of the armature 74, the nut 70 drops along the screw 69 by the distance between two successive rows of wires on the finder board.

As shown in FIGS. 24, 25 and 26, each set of contact arms consists of three contact arms Z ⁰ Z ^x Z ² , which are carried by bolts 91, 92, 93. The working contact arm Z ° is in the middle. These arms are usually located in its rear position% ° ^ ¹ ^ ^2, shown as 26 in Fig. 24 and in the upper part of FIG.. Each bolt is held by a spring. 109 and is provided with a stop pin 94. The three stop pins of a set are arranged in such a way that the working arm cannot be moved beyond the working wire and the line contact arms can reach the line wires with which they are to make contact. Thus, according to Fig. 25 and the lower part of Fig. 26, the arm Z ⁰ in contact with the wire W, while Z ¹ and Z ^'2 with the line wires L ¹ and L ² are in contact ^b. Each contact arm consists of a metallic head 95 which can be inserted between the rows of wires. The edges of this head are covered with insulating compound 96, with the exception of the cutout made on the underside, which lies over the wire to be connected, so that the head cannot come into conductive contact with the upper row of wires. The arm 98 consists of a spring which is attached to a piece 99 of insulating material which is attached to the end of the associated bolt.

Contact arm selector.
The viewfinder also has a contact arm selector mounted on the frame 67 and designed to allow only a single set of contact arms at a time to make contact with the wires of the connecting board while preventing the remaining sets of contact arms from doing so.

/ 16

For this purpose, the contact arm selector can work mechanically by selecting all the sentences, with the exception of the chosen one, prevents them from being opposite them on the finder board Touching contact wires, or it can act electrically by only touching the selected ones Switches contact arm set into the circuit of the telephone connection or leaves it switched on in the same.

It is clear that the various sets of contact arms must be mechanically independent of one another if they are permanently in electrical communication with one another, and that they must be electrically independent of one another if they are mechanically connected. An example of the first-mentioned type is shown in FIGS. 24 to 26, in which all mutually corresponding contact arms of the various sets of the same seeker are electrically connected to a common wire, ie all contact arms Z ' ⁰ are connected to a wire 127, all arms Z ^{1 are} connected to a wire 128 and all arms Z ' ² connected to a wire 129.

The contact arm selector consists of two parts. One part consists of one vertical shaft 100, which at different heights with lifting disks 101 to act is provided on lever 102. For each set of contact arms there is a lifting disc 101 and a lever 102 is provided, the lifting disks on the shaft offset from one another are arranged. At each end of each lever 102 there is a thumb 103 in FIG Rotatably mounted in such a way that the lever 102 is set in a swinging motion, when the thumb of a lifting disc rotating in the direction of the arrow 101 is hit (Figs. 24 and 25), while the thumb is turned during a rotation of the Stroke disc rotates freely in the opposite direction without having to click on lever 102 To exert an effect. The other end of each lever 102 is through a slot and a bolt 104 connected to a bell-like locking piece 105, which in horizontal Guides at right angles to the bolts 91, 92, 93 can be moved. Every Locking gate 105 is provided with three triangular openings 106 into which pins 107 enter, which extend from the bolts 91,92,93 upwards. For each bolt is such an opening 106 is present. Each opening has the shape of a right-angled Triangle, the Hvpotenuse 108 serves as a thrust surface to the pin 107 and the to move the same connected bolt. The bolt is in this way contrary to the Effect of his spring 109 pushed back, when the plate 105 is displaced in its guides in one direction.

The other part of the contact arm selector consists of a second shaft 110 with lifting disks 111 which act on the levers 112 through rotatable thumbs 113. These levers are connected by pins and slots 114 to locking plates 115, in whose triangular openings 116 pins 117 enter. The inclined surfaces 118 of these openings are opposite to the inclined surfaces 108 of the openings 106 of the locking plates 105. A lifting disc 111, a lever 112 and a locking plate 115 are provided for each set of contact arms. The locking plates 105 and 115, which belong to the two parts of the selector, are above and respectively. below the bolts 91, 92, 93 of the sets of contact arms, and the pins 107 and 117 of the bolts engage in the openings of the plates 105 respectively. 115 a. The levers 102, 112 are moved in opposite directions by their lifting disks. The springs 119 are used to keep the levers and locking plates in their normal position of rest. In this position, the pins of the bolts 91, 92, 93, which enter the triangular openings ″ of the plates 105 and 115, are usually pressed tightly against the bases of the openings by one or both plates, as shown in FIG However, if the shaft 100 is rotated in such a way that any one of the lifting disks 101 acts on the corresponding lever 102 and the plate 105, this is displaced so that the inclined surfaces of the openings no longer prevent the forward movement of the bolts 91, 92, 93. The forward movement of these pins can, however, only occur when the associated plate 11 5 no longer holds the pins in. This happens when the shaft 110 is also rotated into such a position that the corresponding lever 112 is moved by its lifting disc 111 Conversely, the plate 105 can also be left in such a position that it does not touch the contact arms of the set to which it belongs changes, and the plate 115 can be brought into the appropriate position by the lifting disc 111. The three bolts are completely released in this way and pushed forward by their springs 109 so that the contact arms Z ° Z ¹ Z ' ² carried by them form contact with the wires W ^b L ¹ Z / ^{2 of} the wire row in front of which the contact arms are brought was. The forward movement of the contact arms is limited by the stops 94 so that the incision 97 of each arm comes into engagement with the associated wire. This working position of the contact arms is shown in FIG. 25 and in the lower part of FIG.

The shafts ioo and ι ίο receive their rotational movement by switching wheels 121, in which the switching pawls 122 attached to the armature levers 123 of the electromagnets MM ^{1 engage.} Coil springs (which are not shown) tend to turn the two shafts back into the rest position, which is prevented by the pawls 124, which hold the shafts 100 and 110 in the positions in which they have been brought by the electromagnets MM ¹ . There are as many lifting disks on each shaft as there are sets of contact arms in the viewfinder. whose two locking plates simultaneously allow the forward movement of the contact arms and leave them in the working position.

If in this way the gontact arms of the viewfinder down to the contact wires of the person to be called Different cases can arise.

Line free.
First case: "Line free".

As soon as the brushes of the distributor G had reached position g ⁱ as a result of the current consignment no. 8, the working ^{contact arm Z 0} (of the released set of contact arms) was replaced by 127, 7, the brush of the sector IIG and 542 (FIG. 2 b) , connected to the two electromagnetic test switches N ¹ N ' ³ , which are connected in series, and of which N' ^{2 is connected} to earth.

Examination of the line.

If the line of the subscriber to be called is now free, the working wire of this line is through spring α ² , wires 508, 50g and the coil of the relay ^ i. ² (its own line) connected to the earth, as from the. In Fig. 2 a shown rest position of the connections of the working wire W ^b can be seen .. But is the. Working contact arm Z ^{0 of} the viewfinder is in contact with a working wire W ^bl , which is earthed, so the test switches iV " ¹ N ' ^{2 are} not activated, and the calling participant who is listening on the earpiece will not hear any noise emitted by the alternating current source V. which would tell him that the line is occupied.

By pushing the handle of the electricity transmitter to the "right," the calling subscriber sends the closing flow, which belongs to the genus of distribution flow and acts on the distributors F and G. First, the distributor G is considered, its brushes reversed advance one division and reach position g ^b . The current of battery g ¹³ passes through the armature and the rest contact of the electromagnet g ⁿ , the contact springs n ^c 'n ⁷ , the electromagnet N ⁰ ', wire 543, the contact pair g ^r ° of the first sector IG, 544, the armature n \ and the rest contact of N \ 545, the spring κ ⁴ and the rest contact of the switch N ' ² , 546, 547 ,; and the armature and the rest contact of the indifferent polarized relay O, whose coil has two windings, and finally 548 'into the circuit of the commutator P, which is provided with a double winding and two contact springs p ^l p' ² , so that the armature ρ is attracted and the two contact springs j; ¹ p ' ^z on expresses their work contacts. The current of the battery p ° goes through the second circuit of P, the work contact and the spring ρ \ the wire 128, the line contact arm Z ¹ , the line LK the resistor 196, the bell 199 and the current indicator 197 of the called subscriber.

Since bells are used which act by short-circuiting and not by switching off their coils, the circuit of P remains closed and the bell continues to ring until the participant removes his earpiece from the hook and thereby removes the earth circuit and finally the interruption causes this circuit. This will be discussed in more detail below.

There is no change in the second sector HG and the fifth sector VG of distributor G. By means of the third sector III G sends a battery n ° (Fig. 2 b), which by the touching springs g ⁷ g ^s (Fig. 17), 550 in the fifth position of the distributor, the armature n ³ and its rest contact and 551 Erdschlufs receives, through the wires 552, 8, 9, ro, the spring r ^l and their rest contact 553 and 554 an uninterrupted current in the electromagnet Q. (Fig. 2a and 29), which regulates the movement of the connector, the together with the above-mentioned viewfinder forms the present connecting device. This connector then begins to move across the connector board, with its working contact arms F ⁰ J ^ ⁰ etc 'brushing over the working contact wires W ^a along the various lines of the connector board, as will be seen from the connector description below.

Interconnects.

The connector illustrated in Figures 27-29 is in its general type, arrangement and mode of operation similar to the viewfinder, but differs from the same in different

different points. It also consists of a rack or frame that can slide in vertical guides, with as many sets of contact arms as there are sets of five rows of wires in the connector board. However, it is not moved downwards in its guides like the seeker, but, as soon as it is triggered by a single extended stream (which, as mentioned above, is sent in response to the final stream from the seeker distributor), it is continuously moved Movement downward. For this purpose, the two line Contacte Y ¹ Y ^2, are found each set of contact arms usually such (as shown in Fig. 28 at y ¹ and y ¹⁾ in the viewfinder by suitable devices besides working position, while the Arbeitscontactarm is available and by Spring is constantly pressed forward, so that the working arms drag when the connector is moved over the working wires W ^{a of} the connector board. As soon as one of these work arms Y ⁰ meets the work wire W ^{a of} a calling line, the displacement of the connector is interrupted, as will be explained in more detail below, and the line contact arms of the set to which that work arm belongs are released and with the line wires brought into contact with the calling line. In the exemplary embodiment shown in FIGS. 27 to 29, the connector is moved along a screw spindle 23 1 of a great incline, which is mounted in the frame 66 with ordinary or ball bearings. A ratchet wheel 233, into which a pawl 234 engages (FIG. 29), is attached to this screw spindle 231. The nut 232, which moves along the screw 231, carries the frame 230 with the contact arm sets. The connector begins to move downward as soon as, upon energization of the electromagnet Q, the bifurcated end 235 of the arm 236 of its armature (which engages a pin 237 attached to the pawl 234) lifts the pawl 234 out of the ratchet 233, whereby an arm 238 of the pawl 234 lifts the pawl 23g out of the ratchet. The rotation of the screw 231 in the opposite direction and the return of the connector to its initial position is effected by an electromagnet U ^a , the armature lever 240 of which carries the pawl 23g and an insulated metal piece 241. The latter in turn interrupts the conductive connection between the springs. 242, 243 and 244, 245. The isolated spring 246 and the contact screw 247 serve to establish the connection between the armature of the electromagnet Q and its rest contact. In Fig. 2a this connection is shown as if it were direct.

Fig. 27 shows a set of contact arms in outline, partly in section. The bolt 248 of the working contact arm Y ° is constantly pressed against the working wire W ^{a by its spring 24g.} The working ^{contact arm F 0} is isolated from its bolt and, as can be seen in FIG. 28, is provided with a T-shaped head. The vertical arms of this head are covered with insulating material and are curved somewhat backwards, so that they present a rounded surface, while the central, most protruding part is conductive. The arms are so long that the contact arm cannot penetrate between two adjacent rows of wires. Only the metallic middle part of the T-shaped head comes in turn into contact with the individual working wires. The line contact arms Y ¹ Y ² are similar to those of the viewfinder. They are carried by bolts 250 and advanced by springs 251. Each bolt is provided with a tooth 252, behind which a pawl 253 can snap into place (FIG. 28). The two pawls, which correspond to the two line contact arms Y ¹ Y ^{2 of} a set, are arranged on the armature of an electromagnet R ¹ , which is connected by wire 254 to the working contact arm F ^{0 of the} same set (FIGS. 2 a and 28). When this electromagnet R ^! tightening its anchor, give the pawls. 235 the teeth 252 free, so that the line contact arms Y ¹ Y ² are pushed forward until they hit against adjustable stops 255. in which position they form contact with the line wires L ^l L ^{2 of} the row in front of which they were brought when the connector was moved.

Effect of the connector.
In the fourth sector IVG of the distributor (Fig. 2 b) the battery g ™ (through the circuit described above and 555 and the first winding of the polarized relay O and 556) with the wire 14, 13 to the common changeover switch R (Fig. 2a), which is provided with an armature r and a single contact spring r ¹ , and connected to the wire 12, ii, from where the lines belonging to the working contact arms Y ° y ° etc. of the various sets of contact arms of the connector branch off. The electromagnet R ¹ (FIG. 28), which brings the line contact arms of the relevant set into an operative position, is connected to each such branch. The circuit of the battery g ¹³ is therefore closed by any one of the electromagnets JR ¹ as soon as a working contact arm lying in the circuit of this magnet places a grounded working wire

meets. This grounded working wire can only belong to one calling line. Namely, as can be seen from the foregoing, the connector working wire W ^{b of} a calling line is connected to the ground through the spring a ^{7 of} the electromagnetic changeover switch A ¹ and through 508, 509 and the coil A ^{2 of} its own changeover switch; on the other hand, there cannot be another calling line in the same group at the same instant, since only one selector and one working device is provided for the group. For this purpose the working wires of all free lines are completely insulated, and finally it will be explained further below that the connecting working wire W ^{a of} a line connected by telephone is connected to one pole of a battery, the other pole of which is connected to earth, and that this pole is connected to earth Connector work wire maintains nearly the potential of this battery. As a result, when this battery has a sufficient voltage and is in counter-circuit with the battery g ^ls , and a connector working arm comes into contact with the working wire W ^{a of} an occupied line, a current flows through the mentioned contact arm which is much too weak, to bring the electromagnets JRA ¹ together. From this it can be seen that a current which is strong enough to excite these electromagnets only arises when the corresponding working contact arm of the connector touches the earthed connector working wire W ^{a of} the calling line.

As soon as the working ^{contact arm F 0 has} come into contact with the working wire W ^a (*) in this way, the switch electromagnet R, which is excited, interrupts the excitation current of the magnet Q. at the spring r ¹ , so that the displacement of the connector is immediately interrupted will. The magnet R * is also excited and allows the line contact arms of the associated set to come into the working position, whereby a permanent connection of the calling subscriber through his line lines L ¹ L ² , the line contact arms Y ¹ Y ² and the wires connected to them (131, 132) with the sixth contact pairs g ^{6 of} the third and fifth Sectors III G respectively. VG of distributor G is created (Fig. 2 a and 2 b).

Conversation position.

Finally the polarized electromagnet O is also excited by the same current which sets R and R ¹ into action, its armature leaves the rest contact, interrupts the connection between the battery g ¹³ and the first coil of the switch P, and sends the current of this battery through the branch 15, 16, 17, 532, 18 and the coil g ^1, then the brushes of the Suchervertheilers g DAF rise to a division and g in the position ^above pass, which is the opening position.

The current of the battery g ¹³ , which is the decisive factor in all these effects, must not, however, be interrupted by the fifth contact pair g ^{5 of} the first sector IG as soon as it leaves the brush, since there may be a fluctuation in the various movements that have not yet occurred would be fully accomplished. To avoid this, the first time the current is sent from this battery g ^ls, the electromagnet N ^{0 is} excited (Fig. 2 b), so that its armature touches the working contact and thus forms a path for the current (through n ⁶ n ¹ , Coil JY ⁰ , working contact and armature of this magnet 2Y °, wire 549, attachment g · ⁵ g ^{e of} the first sector IG, wire 544, and further as above), which depends on the position of the brush g of the distributor on the fifth contact pair g ^{5 of} the first sector IG remains independent until the springs n ⁶ n ⁷ are separated from one another, i.e. until the armature of G ^{1 has} completely finished its working stroke and the distributor G has come to the sixth position (Fig. 16).

This last movement produces the following effects:

At the first Sector IG of the distributor, the battery g ^{13 is} switched off, since when the excitation current of the magnet .ZY ^{0 is} interrupted, the armature of this magnet returns to the rest contact; on the third and fifth Sector III G respectively. VG are those of the line contact arms. F ¹ and Y ^{2 of} the connector coming wires 131, 8 and 132 with the wires 19, 20, 21, and 23, 29, 24 (Fig. 2b), which end at the rest contacts of the springs ρ ^λ ρ ^{2 of} the switch P, tied together. As soon as the called subscriber removes the earpiece from the hook and the commutator P returns to its rest position, a direct connection is established between the called and the calling subscriber. In the second sector HG of the distributor, the connection of the working contact arm Z ^{0 of} the seeker to the examination switch N ¹ N ² in g ^{5 is} interrupted, a connection of the same to a battery rv " in position g ^{a is} established, and Z ⁰ in the fourth sector IVG connected to the working ^{contact arm F 0 of} the connector by 127, 7, 22 and 14, 13, 12, 11, 254. As a result, the searcher working wire W ^{b 1 of} the called subscriber and the connector working wire W ^a of the calling party are given a potential which is similar to that of the The closer to battery n ⁵ , the greater the resistance of the coils A ² (of the respective switch-on devices through which these two lines with the ground

are connected) in proportion to the (always very low) resistance of the wires 254, 11, 12, 7, 127, which connect the working arms F ⁰ J ^ ⁰ . The characteristic condition for a busy line is therefore fulfilled for the line of the called party on the searcher board and for the line of the calling party on the connector board.

Separation of the speaking lines. The current which is sent from the battery n ⁵ through the coil of the switch A ^z of the switching device corresponding to the calling line through Y ⁰ W ^a , 507, spring a ⁷ , 508 and 509, energizes this switch, whose armature is attracted, and remains in the operative position as long as this current is flowing, that is, as long as the telephone conversation lasts. All this time and from the moment when the switch A ^{1 has returned} to its rest position, any connection between the lines L ^{1 and} L ² with the main distributor .B, main selector D and working apparatus E is interrupted. At the same time, a junction 557, a ¹¹ , 558 is created by a contact spring a ¹¹ from one pole end of the coil of the changeover switch A ' ² to the contactfedera ^{8 of} the changeover switch A ¹ , which is temporarily isolated. Likewise, the line of the subscriber to be called is cut off from the main distributor, main selector, of their group. The coil G ^{1 of} the distributor G of the seeker used was completely separated from the battery h ^{s of} the polarized relay H ¹ H ' ² during the transition from the fifth to the sixth position and is thus in the position of conversation against all currents which were polarized by the double Transmitter H can be sent, blocked.

Coming to rest the common

Apparatus of the group. This is caused by the rest position distributor. As mentioned above, this distributor is constructed in such a way that it advances two paces for each stream that hits it, and so connected that it receives only the distribution currents, but not the selector currents. So he would be pushed by the fourth electricity shipment from the first to the third, by the sixth electricity shipment from the third to the fifth, by the eighth electricity shipment from the fifth to the seventh position; and in this seventh position f the brushes were before the final stream was sent off. When this current is sent out, like the previous distribution current surges, the brushes of the distributor F move forward or backward by two divisions. by one division during the passage of the current, whereby the brushes come to the position f ^s , and by a second division when the current is interrupted, whereby the brushes come to their initial or rest position. While the brush f of the second sector IIF of the distributor passes over the eighth contact pair f ⁸ , the current from the local battery f ⁿ (Fig. 2a) flows through 560, 561, 562, 563, 564, 565 to the electromagnet i ⁷⁰ . As soon as the armature of F ⁰ comes into contact with its work contact, another path 560, coil F ⁰ , armature, work contact, 563, 564, 565 is open for this current, and therefore the armature of F ^{0 is} also then in his Retained working position when the brush has advanced one pitch. On the other hand, the contacts / ^{8 of} the sector IF and the contacts f ^{1 of} the sector IIF are connected to one another. The contact pieces of the inner circle are connected by the magnet F ⁰ through 561, 566 to one pole of the battery f ^is , while the contact pieces of the outer circle are connected by the wire 28, 27, 26, 25 to the armature of the magnet Q, which the Displacement of the connector regulates, are connected. Another line starts from the other pole of the battery f ¹³ , through 560, 566, the coil of the changeover switch F ¹ , 567, and is connected to the main selector D, where it connects to the selector circuit and its branch d ² d ³ d * and is thus connected to the rest contact of the armature q of the magnet Q. This circuit was interrupted by the movement of the armature q (Fig. 2a) when the connector was set in motion by the electromagnet Q , and it remains interrupted during the advancement of the connector and is only closed when a working arm of the connector is grounded Line of the calling participant and the anchor of Q returns to its rest position. Only then (may the brush f still be on the contact pair f ^{a of} the sector IF or already on the pair f ¹ j of the sector IIF) is the circuit of the commutator F ¹ closed. By means of its armature and its working contact, this changeover switch closes another local circuit of the battery f ¹³ , which holds the changeover switch back in its working position. At the same time, this commutator F ^{1 separates} a spring f ^w from its rest contact and brings a spring f ⁹ into contact with its working contact.

The movement of the spring f ¹⁰ switches off the battery f ⁿ , which held the changeover switch A ¹ by 504, spring λ ⁵ , 505 in its operative position. The changeover switch therefore returns to the rest position, but the distance between the springs in each pair is regulated in such a way that the rest

Mf.

contacts are closed before the working contacts are interrupted, and vice versa. Consequently, the current which reached the coil A ^{2 of} the connector working wire W ^a from the contact arm F ⁰ through the contact spring d ¹ and 508, 509 remains through the contact spring α ^{8 of the} same pair and the connection which 558 and the contact spring a ^{11 of} this switch A? and make 557 with the pole end of the coil, still closed. This coil therefore remains energized and its armature in its working position. At the same time, through 506, the contact spring a ² , 508, 557, springs ¹¹ , 558, spring α ⁸ and 507, the seeker working wire W ^{b is brought} to the potential of the wire W ^a , which potential is almost equal to ^{that of the battery κ 5.} In this way, the characteristic condition for a line used for telephonic speaking also appears to be fulfilled with respect to the line of the calling subscriber.

The movement of the spring f® closes the circuit of the battery b ^a (Fig. 2 a) through the coil B ^{1 of} the main distributor B, 568 and the coil F ^{2 of} the electromagnet, which is used to bring the main selector D back to its starting position. As soon as the coil F ^{2 is} vigorously excited, it brings the main selector D back to its initial position and also acts as a changeover switch by separating a spring f ⁿ from its rest contact towards the end of its armature stroke. In this way, the various ^{local circuits fed by the battery / 13} are interrupted, the electromagnet F ⁰ and the commutator F ¹ return to their initial positions, the spring f ⁹ is separated from its working contact and the brushes of the main distributor B (since the circuit the battery b ⁶ is interrupted in this way), advanced by one division and come into the rest position. As soon as the connection between the calling and the called subscriber's line is established, the connection of the other lines of the group with the battery b ^{h is} restored, and the devices intended for common use are separated from the calling line and returned to their normal - or brought back to the rest position so that they can be used again by another member of the group to which the caller belonged.

End of conversation. After the conversation has ended, the viewfinder and the connector that were used, as well as the associated auxiliary devices, should be returned to the rest position. The return of the viewfinder to the initial or rest position is brought about by two successive movements. The first brings the contact arms, the second the entire finder frame in the initial position by lifting the same in stages along its screw spindle 69. This movement is brought about by the electromagnets TT ¹ and T ² .

The return of the contact arms to their rest position is done in the following way. Two vertical rods 125 (FIGS. 20 and 23) are attached to the pawls 124 and remain in a position in which they are held by the T-shaped head 126 of an arm attached to the armature lever 84 of the electromagnet T during the entire downward movement of the viewfinder be influenced. When this electromagnet is excited and attracts its armature, the rods 125 are pushed back and the pawls 124 are brought into engagement with the ratchet wheel 121. The shafts 100 and no are then returned to their rest position by springs not shown in the drawing, so that the contact arms advanced by the lifting disks can be returned to their initial position through the thrust surfaces of the openings of the locking plates when these plates are activated by the action of the springs 119 be pushed back. The rotation of the screw 69 in the opposite direction for the purpose of returning the viewfinder to its rest position is effected by the two electromagnets T ¹ T ² (FIG. 20). The magnet T ² drives the ratchet wheel 71 by means of a pawl 76 connected to its armature lever 77; a pawl 78 engages the ratchet wheel 71 and prevents the same from going back. In order that these parts 76, 78 do not prevent the rotation of the screw 69 in the other direction during the downward movement of the viewfinder, a pin 79 (Fig. 22) attached to one arm of the escapement anchor 74 holds the pawl 78 open when the anchor is first moved Engagement with the indexing wheel 71, while an ann 80 of the pawl rests against the indexing pawl 76, so that the pawls 76 and 78 are brought out of engagement simultaneously with the indexing wheel 71, as shown in FIG. 22 with dotted lines. At the same time, a latch 81, which is rotatably connected to an extension of the pawl 78 and has an inclined surface 82, slides over the inclined end 83 of the armature 84 of the electromagnet -T and is brought into engagement with the armature by a spring 85. This trap holds the pawl 76 and the pawl 78 to engage the ratchet wheel 71 until the armature 84 is withdrawn by the magnet T and the latch 81 is released. The electromagnet T is the one which, when returning

/ X /

bring the contact arms of the seeker to the rest position first receives the Schlufsstromstofs. The pawls 76 and 78 therefore engage no sooner than until they become necessary again. The isolated metallic contact piece 86 (FIG. 21) is attached to the armature lever 77 of T ² and, in its initial position, establishes the connection between the two springs 87 and 88. As soon as the armature is attracted by T ² , this contact piece separates the springs 89 and 90 from one another. In this way, it produces the same effect as the springs t ° and i ⁴ shown in FIG. 2b on their rest contacts, which, as mentioned below, automatically apply the number of current impulses required to return the viewfinder frame to the rest position produce. For this purpose .ist in the branch line 29, 569, 570, 30 (Fig. 2 b), which contains the central transmission battery s ° , also the first winding of an electromagnetic switch S is connected, which has a contact spring s and two different windings. The magnets S ¹ S ² , which have very low resistance and low self-induction, are arranged on both sides of the branch line 29, 30 and in the two connecting lines 20, 21 respectively. 23, 24 switched on, through which the line arms, the viewfinder are connected to the line arms of the connector. The contact spring 7 ^ ³ is kept lifted from its contact t ³ by an insulating projection 67 ^{a of} the viewfinder frame, as long as the latter is in its normal position.

But as soon as the viewfinder leaves its rest position, the spring T ³ touches the with. associated contact the ground t ^3, and, and therefore, the current of the Central battery s °, the first wound onto the switch S once energized (which can only occur when at least one of the participator in ^readiness, is to speak), Sleeping the armature this Changeover switch itself through the second winding the circuit of the battery s ¹ and thus maintains itself in the working position. At the same time, the. Battery s ^{2 is} permanently connected to the spring s . But the circuit of this battery (which is only closed when each of the armatures of the magnets S ¹ S ^{2 is} in contact with its rest contact) remains interrupted in at least one point - as long as both participants do not hang their earpieces and thereby the current of the Battery s ° in both magnets S ¹ S ² have interrupted at the same time. Only then does the current of the battery s ² flow through 571, 572, 573 first through the magnet T ", which influences the device for returning the viewfinder contact arms to their rest position, and then through 574 ^{as a result of the compression of the two springs if 1} ί ² the electromagnet T ¹ , which controls the device by which the viewfinder is returned to its starting position, since the current of the battery s ² passes through the rest contact and the armature f ° - of the electromagnet 7 ' ² to the first winding of the auxiliary magnet T ¹ , which has two windings, it attracts its armature, which at its working contact closes the circuit of another battery t through the magnet T ² and the second winding of T ^1. The magnet T ² attracts its armature, which first supplies the current the battery s ² interrupts and the device, which returns the viewfinder to the rest position, advances one tooth, then, towards the end of its stroke, the spring i ⁴ from its rest econtact separates. Since both windings of T ^{1 are} de-energized, the armature of T ¹ returns to its rest position, and the same is also the case with the armature of T ² , which magnet is also de-energized. The current of the battery s ² is therefore closed again and causes a further shift etc. until the viewfinder has intermittently reached its starting position again, whereupon the spring T ^{3 is separated} from its contact t ³ by the projection 67 ^{a of} the frame 5 now moves from its working position to the rest position and interrupts the circuit of the battery s ¹ . This arrangement differs from an ordinary oscillating circuit breaker in that the armature t ° of the magnet T ^{2 must} make the full possible deflection with each stroke.

At the same time as the battery s ² sends a current to the magnet T , a current passes through 571, 572 and the branch line 3 1, 43, 45 in the appropriate direction through the second winding of the polarized magnet O, around its armature and also through the branch line 31, 43, 46, 47 (Fig. 2b) to the second winding G ^{1 of} the finder distributor G, the brushes of which advance by the last division and return to their rest position.

During this shift, the brush of the sector HG of the distributor G interrupts the connection between the battery h ⁵ and the working contact arm Z ⁰ through 7, 127, and the brush of the sector IVG ^{interrupts the connection of this arm with the working contact arm F 0} through 7, 14, 13 , 12, 11, R ¹ , 254. The changeover switches A ^{2 of} both participants, which no longer receive any current, return to the rest position, whereby the connection between the working wires W ^b and W ^{a of} the two lines (through 506, a ² , 508, 557, α ¹¹ , 558, a ⁸ , 507) is interrupted and the switch-on devices

the same can be returned to the initial or rest position.

The connector becomes like the viewfinder with two successive movements to the Return to the initial or rest position: first the contact arms should be withdrawn, then the whole frame can be pushed up.

For the purpose of returning the contact arms Y ¹ Y ² (Fig. 27 to 29) to the rest position, each bolt 250 carries a pin 256, and there is an oscillating shaft 257 for each set of contact arms, the fork-shaped arm 258 of which with its crosspiece on both pins 256 can act. The shaft 257 carries an arm 259 at right angles to the arm 258, through the forked end of which a pull rod 260 passes. The latter is connected at its one end to a spring 261 and at its other end to the armature 262 of the electromagnet U ¹ and carries rings 263. When the bolts 250 are released and moved forward by their springs 251, their pins 256 rotate the arms 258 and 258 259, so that the arm 259 comes into close contact with the relevant collar 263. If the electromagnet U ¹ is now excited and attracts its armature, the collar 263 acts on the forked arm 259, rotates the shaft 257 in the opposite direction and, by means of the arms 258 and the pins 256, pulls the bolts 250 back, so that their teeth 252 engage the pawls 253 again. The rod 260 is common to all bolts of the contact arm lugs of the connector. Therefore, when the magnet U ¹ is excited, each contact arm attachment which was in the drive position is brought into the rest position. The Stromschlufsfedern 264,265 are used to close the circuit shown in Fig. 2a, through which the Stromstofs is sent to the electromagnet U ² U ³ , which move the connector up to its starting position after the contact arms have been pushed back.

Both effects are achieved in the following ways:

At the moment the connector left its rest position in order to establish the connection with a calling line, a contact spring U ⁴ (which is usually held away from its contact by a projection 230 ** of the connector could (Figs. 28 and 2a) will) touch this contact connected to the battery u ^l. At the following moment, when the connector comes to the calling line and the changeover switch R is energized by battery w " , its armature r is held back in its working position, so that the current of the battery u * first (through junction 32, 33,34, 35, 36, the armature r and its work contact and 575) to the first winding of the two-turn switch U and then through the armature u and its work contact and branch 576 to the second winding of this switch Armature u of changeover switch U is therefore held in the working position regardless of the movements of armature r and establishes a connection between the rest contact of armature r and magnet U ⁰ by means of its spring u ^l and its work contact and wire 577. As soon as the Current of the battery w ^{5 is} interrupted by the changeover switch R by the return of the brushes of the viewfinder distributor G to their initial or rest position, the Ank returns he r back to the rest position, and the current of the battery M ⁴ flows continuously through spring r, 577 and spring u ^l and 578, first through the magnet Z7 °, which attracts its armature u ° , and then (through 36, 579, the Armature ii ° and its working contact and 580) by the magnet U ¹ (Fig. 2 a and 28). This electromagnet U ¹ is excited and attracts its armature, the movement of which causes the contact arms of the connector to be returned to the rest position. When this armature reaches the end of its stop, the current through the junction 33, 581, 582, 583 of the rest position device U-U ^{s is} closed. This device is similar to that of the viewfinder. U ² is an ordinary electromagnet with two windings, while the electromagnet U ^s (Figs. 2a and 29) moves the parts by which the connector is intermittently returned to its rest position. This backward movement is interrupted when the spring U ⁱ is lifted from its contact by the projection 23 o * ¹ and thereby the current of the battery is interrupted, so that the changeover switch U and the magnet U ^{0 are} de-energized. All the parts for establishing and maintaining a telephone connection between two lines are now in the initial or rest position.

Line occupied.

Second case: "Line in telephone connection".

As mentioned above, the working wire W ^{bl of} a line, which is in telephone connection, is connected to the relevant search board on the one hand with one pole of the battery w ⁵ , the other pole of which is connected to earth, and on the other hand with the coil of the Magnet A ² and the earth connected. This working wire W ^b therefore receives

a potential which is closer to that of this battery, the greater the resistance of coil A ² . Assume that two participants are in telephone connection with each other, and a third participant now sends the above-mentioned electricity transmissions, including the final electricity No. 9, in order to connect with one of these two participants. As soon as the brushes of the distributor G, which belongs to the seeker of this third participant, have been brought into position g * and a set of contact arms of this seeker has been brought into working position, so that the working arm Ζ ^{ΰ of} this set with the working wire W ^bl the occupied line comes into contact, which, as already mentioned above, is connected to the battery w ⁵ through the distributor G of the viewfinder that is in use, is fed from this battery n ^h by the working wire W ^{bl of} the occupied lines, the working arm Z ° of the seeker of the third participant, the wire 127, the wire 7 and the contact pair g ^{i of} the sector HG of the distributor G of this same seeker and 542, an electric current is sent to the two electromagnetic test switches N ¹ and N ' ² , which are connected to anchors n ¹ n ³ and are provided with contact springs n ² n * influenced by these. This switch is used to check in the following way whether the line to be called is free or not. The armature n ^l n ^s and the contact springs n ² n ^{4 are brought} into working position by the current of the battery rr " running in the manner described above . An alternating current generator V is (through a capacitor v, the spring n ^{2 of} the switch N ¹ and the electrical Stromstöfse of the alternator V whose work Contact and 584) with the property of the desired compound in use Auswählerstromkreis CId ² Cl ¹ Cl ⁰ at d ° before the connection point of this circuit to the circuit of the polarized receiver H this Auswählerstromkreises'verbunden. therefore through the wire d ° d ⁱ d ² the common metallic frame d to Hauptauswähler D of the group to which the third participator belongs is transferred. this Hauptauswählers are on which all the springs clamped d, but by the condenser y ^1, the Wire 585 and the primary coils of two induction coils II ^{1 are} connected to earth ntacte the sectoral IIB and IIIB and the points ii ¹ switched on, at which the branch lines from the switches of all line wires of the group converge for the purpose of connection with the main distributor B, which forms part of the group plant.

Since it is assumed that the brushes of the main distributor B are in the fourth position, the electric current surges of the generator V are transmitted by induction to the line wires L ¹ L ' ² of the subscriber who calls, as assumed, in vain, so that the subscriber calls on his listener perceives a characteristic noise which indicates to him that the line he wants is occupied.

Since the desired telephone connection is currently impossible, it is in vain calling subscribers in the manner described above to shut down his own power transmitter and for any other call to make available. But this has the effect that all parts which are involved in the experiment of the call in the Central Station were put into action, returned to their idle position will.

Since the connector (in the connection device which the unsuccessful calling subscriber tried to use) has not left its rest position, it follows that when the brush of the distributor F (belonging to the set of devices of the group of that subscriber) passes through this circuit stream is forced to go over the position / ^{8 of} the sector IF and come to rest in the position f ^{1 of} the next sector IIF, the circuits described in the previous case for returning the main distributor and the main selector are already closed, without a gap in the armature of the changeover switch Q., so that these devices are immediately returned to the initial position.

As for the seeker (in the connecting device used by the unsuccessful calling subscriber), the brushes of his distributor are brought into position g · ⁵ by the closing current, in which the test commutators N ¹ N ² remain in their operative position and with the working arm Z ⁰ (that finder) and the working wire W ^{b of} the connected line remain connected. The battery n " is switched off at the rest contact of the armature w ³ , and the earth is connected (through the armature rc ³ and the springs g ⁷ g ^s ) to the local battery η , which controls the switch N ' ² and the electromagnet 5 ° independently of the other apparatuses in their operative positions.Now the closing current material reached the coil G ^{1 of} the distributor G (the seeker used by the unsuccessfully calling subscriber) only via the small electromagnet g ⁿ (Fig. 2b), whose armature was attracted. Consequently, at the moment in which the

split brushes reached the position g ^s , the battery g · ¹³ cut off from the contact pair at g " ^{5 of} the sector IG. If, however, in the following moment the current of the secondary current material ceases to flow, and the armature of the coil G ¹ , which is the brush of the distributor G pushed to the fifth position, comes to rest, and the electromagnet g ^{11 is} no longer excited, its armature returns to the rest position, and the current of the battery g ^vi (which is carried on as described above via the electromagnet N ° after the brushes have left the contact pair at · g ⁵ ), (through the contact pair at ^ ^{5. of} the sector IG the armature ¹ and its working contact and through the line 17, 18) into the coil G ^{1 of} the above-mentioned distributor G sent, whose brushes are advanced by a division and reach the position g ^e . It is only necessary that the armature of the electromagnet G ¹ return to its rest position a little more quickly than that e of the electromagnet g ¹¹ , which can be easily achieved by suitable adjustment.

Because the brushes of distributor G (of the viewfinder used by the unsuccessful calling subscriber) move into position g ^a , the connection between the working arm Z ⁰ (that set of contact arms of the viewfinder used during the call) and the switches N ¹ N ' ^{2 is} interrupted, so that while the commutator N' ² remains in its active position by the battery η , the other switch N ¹ returns to its rest position, and the current of the battery η (through the contact pair at g ^{6 of} the sector IG , the armature n ¹ and its rest contact, the spring n * and its working contact, and the wires 37, 38, 39,40,41,42) via the second coil of the switch S to the spring T ^a and its earth contact t ³ (Fig. 2 b). Since also the branch line 29, 569, 570, 30 between the anchor and the rest contact of the. Electromagnet 5 ° is interrupted, the two electromagnets S ¹ S ^{2 are} necessarily in the rest position. If, therefore, the armature of S ^is attracted by the current of the battery g is and is held in its working position by the current of the battery s ^l , the battery s " (as described in the previous case) can come into effect to divert the distributor G and By the fact that the distributor G returns to the rest position, the earth connection of the battery η at the springs g ¹ g ^{& is} interrupted, and the changeover switch N ^{2 also} returns to the rest position returned to their resting position.

Third case: »Seeker is in use".

It can happen that after the beginning of a telephone conversation, which a Participants of one group lead with one of the other group, a third Participants in the first group to speak to a fourth in the second group wishes. Now there is the finder which this third participant must use, already in use. It must therefore not be possible that this third participant can disrupt the connection of the first or eavesdrop on the conversation being conducted, and it He must be informed that he is not currently dealing with the desired Can contact participants. This can be done in the following way:

When the brushes of the distributor G of a seeker are in their sixth position, ie the talking position, any connection between the battery h ¹ and the coil G ^{1 of} the seeker distributor G is interrupted in the fifth sector VG; consequently, the current surges sent by the third calling subscriber cannot ^{reach the coil G 1} and bring the relevant seeker distributor G from this conversation position to another; and since the magnets KMM, which regulate the movements of the various parts of the viewfinder themselves, the current surges of the battery h ¹ only resp. are accessible in the second, third and fourth positions, the whole seeker remains completely unaffected by the surges of electricity from the third participant. Since, on the other hand, the connector connected to this searcher has left its initial or rest position, the spring V ' ² (Fig. 2a) has made contact with the spring v ² , and when the third calling party (after having received all electricity consignments No. 1 to 9) listens on his earpiece, the rest position distributor F belonging to the group of the first and third participant, which is in its seventh position ^{, sets the connection between the alternator F 1} and the induction coils / 7 ¹ (through 586, the seventh Contact pairs_ / ⁷ , the first sector IF, 587, the spring F ² , your contact v ' ² , the line d% d ^h , d \ d ³ , d ² , the contact spring d of the main selector D, the metal piece D ⁰ and of the condenser v ¹ ) , and a signal is therefore given to the third subscriber by the familiar noise in the receiver that the desired connection cannot be established.

Twin seeker.

It is clear that the above-mentioned chance can occur all the more frequently, the greater the amount

Is the number of lines belonging to a group. However, the greater the number of lines in a group, the more complex and difficult the corresponding searchers are. For these and other practical reasons, it is therefore desirable to limit the number of lines in each group. On the other hand, it is desirable not to make the number of groups too large, since then the main selector would be too involved. These two contradicting conditions can now be met by the fact that with each selector circuit, in addition to the seeker mentioned up to now, there is also one (or several) so-called "twin seekers" (the special circuit of which is detailed below with reference to FIGS. 3a, 3b and 3c is explained), is connected. These two seekers lie on the seeker boards of different groups of lines, which may be conceived as possible subdivisions of a larger group of lines, and one or the other of these two seekers is put into action according to the polarity of the first given stream (distribution stream) . This is just the case for the two seeker distributors G and G ² and the seekers belonging to them, which are controlled by the selector circuit ά, ά ^, ά ^, ά ⁰ and their double receivers H , and for the two rest position distributors F and F * . The same main selector is able in this way, without being more involved, to control twice as many seekers as would otherwise be possible by placing each circuit of the main selector (for the use of a group of lines) each of, for example, two seekers (called twin seekers) can regulate, and each of these viewfinders is in electrical communication with a special connector. These two connectors, which are thus indirectly connected to the same selector circuit, are called "twin connectors". As each twin connector. can only be set into action with the aid of the twin seeker connected to it, each of these twin seekers and the twin connector connected to it together form a connecting device, and these two connecting devices are completely independent, except that they are regulated by the same main selector.

In the following it shall be explained how the fact that a called seeker is already in use does not result in the inactivity of the twin seeker, who is regulated by the same circuit of the main selector. It has already been mentioned that, with the first switching movement of the brushes of the finder distributor G, the electromagnet G ^{3 of the finder distributor G 2} corresponding to the twin apparatus is completely out of connection with the battery . set, and so held in the rest position; consequently not only this distributor G ² , but also the seeker connected to it, whose organs are only accessible to the selector currents in the second, third and fourth position of the distributor G ² concerned, remain of the streams that send the twin seeker and his distributor G in Put into action, completely unaffected. If now the brushes of the distributor G from the fifth to the sixth position. (Speaking position), i.e. as soon as the connection used by the distributor G and the seeker and connector connected to it is fully established, and the main distributor and main selector of the group that were in use become usable again, becomes on the fifth sector VG the connection between battery h ³ and coil G ^{1 of} this distributor G is interrupted. On the other hand, one of the five metal pieces 222 of the disk 219 (Figs. 16 and 17) sitting on the axis of the finder distributor G establishes the connection between the two contact springs g ⁹ g ¹⁰ , - and since this with the two contacts of the first pair g ¹ are connected to the first sector IG (g ⁹ , 588, 535, η and g ^w , 589, 534), the connection that was interrupted when the distributor G was first moved is restored and the coil G ^{3 of} the Twin distributor G ² can again receive distribution streams, and immediately afterwards the twin seeker can be put into action at will by means of selector streams. Incidentally, when a searcher is in use, it in no way means sending the signal indicating that the line is busy to the subscriber who wants to use the twin seeker. As noted above, the distribution currents for influencing the distributors G ¹ G ² controlled by the same selector circuit are of opposite polarity. Now one of the rest position distributors F only corresponds to currents of one polarity (e.g. those which act on G ¹ ), while the distributor F ⁱ only corresponds to currents which act on the coil G ^{3 of} the distributor of the twin apparatus. As soon as the brushes of the distributor F * (which is influenced in the same way as has already been explained with reference to the distributor F ) reach the position f ⁷ , the power generator V ^{1 is} connected to the spring F ⁴ by 590, 591, which is attached to the twin connector mentioned and performs the same functions as has already been described with reference to the spring V ' ² . As a result, takes

the participant, who wants to use the twin finder and listens to his receiver before giving off the final current, does not hear any noise if this twin finder is not already in use, since in this case the twin connector is still in its rest position and the spring F ⁴ is separated from its contact ν ⁴ , which (like the contact ν ² ) is connected to the main selector D and the induction coils J / ¹ . Since the contact is interrupted F ⁴ may be from the generator ¹ F no electric pulse through the conduit to the Inductionsspulen ^7/1 and from these to the lines of the line part taker which wants to use the twin viewfinder reach. If, on the contrary, the twin finder is already in use, the twin connector is no longer in its rest position, the spring F ⁴ has reached its contact ν *, and the current surges from F ¹ to the induction coils II ¹ and from them come through Induction to the participant himself and show him that the line is busy. It should be noted that the action of distributor F ^ is similar to that of distributor F , although not all of the circuit connections of the former are shown. The electromagnet Q. ¹ regulates the movement mechanism of the twin seeker. The operation of this electromagnet is similar to that of the electromagnet Q described above.

If the number of participants is so great that they have a greater number of Requires selector circuits than that described in Figs Main selector, which has nine circuits, can be satisfied, so can one use two means:

1. A type of composite selector, consisting of a primary main selector of the type shown in FIGS. 12 and 13, of which the selector circuits lead to the contact pieces -D ⁰ as many secondary main selector, as selector circuits in the main selector, the primary and secondary selectors are similar in construction and mode of operation. In this case, two toothed racks, which carry exactly the same contacts as the toothed rack 145, are connected between the toothed racks 144 and 145 of the subscriber's power transmitter. The first current that is sent acts in the manner described on the switch-on device, while the four following current surges determine the choice of first the secondary selector, then the selector circuit dependent on the secondary main current selector.

2. A single main selector with more

than two members, which regulates more than nine selector circuits. For example, a selection can be used which has 27 contact springs and three links, each of which consists of three rods moved by special electromagnets, each rod acting on nine contact springs by means of nine isolated stops. In order to put such a three-member selector into operation, a further rack is inserted between the racks 144 and 145, which rack carries similar gontacts as the rack 145. In both cases, as many contact pairs must be added to each sector of the main distributor B as racks have been switched on in the current transmitter; the other parts of the apparatus remain the same.

In order to facilitate the understanding of the effect of the current surges given by the calling subscriber and to summarize the changes in the electrical connections that occur one after the other when the above-mentioned arrangements are influenced, reference is made to FIGS. 3 a, 3 b and 3 c, which schematically represent these connections . The connector boards are here with l ^a , II ^a , III ^a , IV ^a , Y ^a , Vl ^a and the finder boards with. I *, II *, IIP, IV * ₅ V *, VI *. Opposite the connector boards, the six connectors i ^a , 2 ^a , 3 ^a , 4 ^a , 5 ^fl , 6 ^a are shown, the contact arms of which are denoted by three lines. Of these, the middle arm F ^{0 is} the working arm, while the two side arms Y ¹ F ^{2 are} the line arms. Similarly, opposite each finder board are six finders 1 *, 2 ^b , 3 *, 4 *, 5 *,. 6 * arranged, each with a working arm Z ⁰ and the line arms Z ¹ and Z ² .

Only those connections are drawn to which reference is made in the explanation. The circles below the viewfinder indicate the associated distributors G or G ² . The electromagnets G ¹ or G ³ , which regulate the movements of these distributors, are shown schematically under these circles.

With reference to the connections that changed as a result of the movements of these distributors it should be emphasized that when the circle appears to be traversed by a line, the connection is made along this line. However, where this line (within or outside this circle - (Q) - or --I Ql-) appears interrupted, the relevant one is Open circuit.

On the right-hand side of each finder board are shown the switch-on devices for the relevant lines of the board (parts AA ¹ A ^{2 of} each switch-on device are illustrated in a schematic manner), as well as the main distributor B, the main selector D.

and the working apparatus E of each group (Figs. 3a, 3b. and 3c).

All lines of group No. 1 are switched off, none of them is calling, called or connected; only the viewfinder 1 ^b Group I is drawn in the position in which it can receive Auswä'hlstromstöfse of a line of group HI, and it is therefore the Vertheiler G shown this viewfinder as that controlirt the twin viewfinder by the same selector and is shown opposite the finder board of group II, locks in the rest position.

The group II of Fig. 3a is shown in the moment after the calling line has sent (the top of the board II ^'1) Stromstofssendung Nos. 1, thereby the Hauptauswählers D was connected to the transducers C and after the Stromstofssendungen No. 2 and 3 have acted on the main selector, whereupon one of the selector's circuits at d is closed. The battery a ¹⁰ is connected to the working wire W * (*) of the calling line, so that no other subscriber can connect to this line. The remaining lines of the group are separated from the battery b ⁵ .

In group III (Fig. 3 b) the calling line (the third from the top) is shown at the moment after the electricity consignment no are transmitted in the form of local currents) pass the closed selector circuit and act on the polarized double relay H. It was assumed that the two twin seekers, which are regulated by the closed circle of selection, and which are designated by 1 *, opposite the search boards I *, II * of groups I and II. The seeker of group I is just being put into action and the group II seeker is in the state in which the coil G ^{3 of} its distributor G ² is locked in the rest position.

Group No. IV of FIG. 3 b shows the case when all streams of material are sent out with the inclusion of the final stream No. 9, and it is checked whether the line to be called is free. The calling line is ^{the second from the top on board IV 2} and it has been accepted:

a) that the seeker 3 * of group III in Action has been taken,

b) that his arms with the line to be called (the second from the bottom on the board IIP) Contact and

c) that this line is not occupied

The twin of the seeker used, which is located in front of the board IV *, is locked in the rest position ^{with the coil G 3 of} its distributor G ^2.

Group V (FIG. 3 c) shows the state of the devices which is present at the moment when the calling line (the lowest on board V ^a ) passes the searcher 2 * in front of the called line (the uppermost aiii board VP ) has brought, and the participant, after being convinced that this line is free, has given up the final current which sets the connector in motion. However, the connector has not yet met the work wire W ^a {*) on the connector board V ^a , but the battery g ¹⁵ connected to the work contact F ⁰ through the commutators R and R ¹ is ready to move the connector to inhibit as soon as the working contact arm F ⁰ touches the working wire W ^a (*) , which is connected to the ground by the coil A ' ² of the switching device belonging to the calling line. . .

A connection was shown between the bottom line of the connector ^{board III a} and the bottom line of the connector board IV *, to show how the working wires W ^a {*) and W *>'(*) of the lines connected for a conversation Have the potential of the test battery n ⁵ .

Group VI (Fig. 3c) illustrates the state of the apparatus at the moment when the connector stopped after reaching the working wire W ^a (*) of the calling line (in this case the lowest on board VI ^a ) and in which the called subscriber (whose line in this case is the fourth from the top on board VI *) has removed the earpiece from the hook, so that the two subscribers can conduct a telephone conversation.

The working wires. W ^a (*) and W * (*) of the calling line are through the electromagnet ^. ^{2 of} the switch-on device belonging to this line are connected to one another. The working wires W ^a (*) and W * (*) of the called line are similarly connected to one another, and finally the working wires of the calling party are connected to those of the called party (through the distributor G of the viewfinder used) and are connected to the Test battery rv " in connection.

The connection of the other lines of the group with the battery b ^s is restored; the devices to be used together (main distributor B, main selector D and working device E) are reset to their rest position, and the coil G ^{1 of} the healing device G of the viewfinder used is in the

Claims (4)

against all currents which flow through the | polarized double transmitter H can be sent, while the twin ^{seeker with the coil G 3 of} his distributor G ^{2 is} connected to the same relay H , so that he is ready to take effect. With respect to .the operation of the twin viewfinder, it is assumed in Fig. 3 a, that the third line (from above) of the group III like, and that both controlled through the closed main selector circuit twin detector 1 * from Group I and 1 ^b of group II are . Of these, the former is shown in the position in which he is ready to act, while in his twin, the coil G ^{3 of} his distributor G ' ^{2 is} connected to the battery h ³ , and the viewfinder itself is locked in the rest position. In Figure 3b, the calling line is the second from the top in Group IV and the line to be called has been checked and found free. The viewfinder coming into use is 3 * of group III, and its twin (namely 3 * of group IV) is shown in the position in which the coil G ^{3 of} its distributor G ² without connection to the battery h ^a and the viewfinder itself is established in the rest position. In Fig. 3c the telephone connection between the calling line (the lowest of group VI) and the called line (the next higher of the same group) is shown. The other lines in the group have re-established their connections to the battery ¥ " and the BCDE arrangements, which are common to all lines in the group, have been returned to their rest position. The ^{coil is on the finder used (namely 6b} of group VI) G ^{1 of} its distributor G blocked in the rest position against currents of the polarized double relay H , while the coil G ^{3 of} the twin finder of the distributor G ^{2 is switched on} in the circuit of the same relay and is thus made usable for use. Godfather τ-An Proverbs: i. Automatic telephone switch in which the lines of subscribers are grouped together at the mediation office, characterized by the fact that there is a single electromagnetically operated plant for each group, which from each line of this group by a number of current surges of the same or the opposite direction can be set in motion in such a way that it by means of a connecting device, of which there is so much for every group exist as groups, the calling line with the line to be called connects, whereupon it immediately returns to its rest position and for a new call from any participant the Group becomes available. 2. Device of the type specified under 1., in which the connecting device of two independently movable, permanently connected to one another Contact devices, one of which (seeker) with the two wires of the subscriber to be called, the other (connector) to the two wires of the calling party through it is brought into connection that the seeker of that group in which the management of the subscriber to be called by means of one of the calling subscribers through a number of currents push one or the other direction controlled switching device in front of the Wires of the desired line is pushed, whereupon, if the desired line is free, the connector is automatically pushed in front of the calling line and with this is connected. . . 3. Device of the type specified under 1., in which the movable contact devices are provided with several jointly moved contact arms, each of which via a group of line contacts is moved away, so that by suitable choice of the contact arms each line contact with only a small displacement the poor . can be connected to the line. 4. Device of the type specified under 1., characterized in that, to the Not having to make the viewfinder excessively large, with each viewfinder a second, so-called one Twin seekers of the same institution are connected in such a way that, according to the polarity of the two, they come first electricity sent to the seeker . neither the seeker nor the twin seeker in activity in any other way is set. In addition 7 sheets of drawings.