DE2427584A1 - KEYBOARD TELEPHONE - Google Patents

Description

Dr. Herbert Scholz

tentanwalt

Applicant: PXE LIMJiEED ^ * * * * ^ *

E LIMJiEED

File No. PP 1H9. ,

- 6 ο 6.74 DEEN / EVH.

, e No.

6 ο 6.74

"Keypad telephone ¹¹

The invention relates to a keyboard telephone

with electronic means for generating counting pulses

pressing the pushbuttons, since there are no such devices rotating dial is present, the functions of the usual short-circuit contacts are met on other yeise, e.g. * by using an electromagnetic relay, Die Short-circuit contacts are used to short-circuit the various Impedances in dex * telephone line during transmission of dialing impulses, in the case of a keypad telephone, the Strowger-type impulse series (= loop under ~ refractive pulse series) is generally a Another electromagnetic relay for supplying the loop interruption pulses is used, as is well known, for delivering.

409 8S1

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des to operate these relays and the electronic ones Devices required a stationary battery arranged in the telephone, which is vcn the main battery in the Central is charged from over the telephone line.

The stationary battery can be charged during the calls and / or when the device is idle. In order to be able to expect reversal of the line polarity, the battery has to be connected to a diode rectifier bridge

are fed, thereby generally on the rectifier ι '. ·

there is a voltage drop of approximately ten volts,

this effective line voltage loss reduces the maximum line length, whereby the device works properly. If the battery is charged with a low current (e.g. approx
mentioned Kachteiles, but other difficulties arise. In order to enable normal line test work in the control center, a charge cut-off arrangement must be available in series with the telephone battery in order to reduce the charge current of 3 mÄ under these circumstances. to interrupt. The setup of this arrangement enables the remote speaker to be connected in parallel to a normal dial telephone, but it cannot be connected in parallel to another keyboard telephone, because in this case the total charging current in the rest position would exceed the maximum permitted.

. 409801/0978.

■ - ". '■ - 3 - 5/29/74.

Another disadvantage of having a battery Telephone is that the battery runs at regular intervals needs to be replaced.

About the various difficulties that the use a battery entails at least partially eliminating, a telephone has been proposed at The bistable relay can be used, i.e. relays that are triggered by pulses in one of the two stable states of the Relays can be brought and remain in the state in which they were brought for the last time, without that Performance is required. In this way, a bistable relay, when used for this purpose, requires the function to meet the short-circuit contacts during line operation no performance. Also for loop break line signaling means the use of a

Such a relay for the JmpulkontPkt _s that only short operating impulses are required for each change of state, which can easily be delivered by a charged capacitor. This makes a stationary battery superfluous. However, the use of bistable relays is complex and has the further disadvantage that the relays have to be made extremely sensitive in order to reduce the power requirement as much as possible, whereby they can easily be switched from one state to the other by shocks or missing pulses can be. That is why further switching elements are necessary in order to create a

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to avoid such malfunction, and the necessary Circuits are involved and therefore expensive.

The latter known telephone is im A microswitch is hooked, which is activated when the Handset is operated. The contact of this microswitch is used to restore the electronic devices to their original state if a call was received during the Dialing is terminated.

The invention aims to reduce or eliminate the above-mentioned disadvantages.

According to the invention is a keypad telephone with an electronic control arrangement for generating dialing pulses by actuating the pushbuttons and with electrical short-circuit contacts, which are mechanically so with the pushbuttons are coupled in that they are put into operation by pressing each pushbutton, characterized in that that a locking member is arranged to the short-circuit contacts after commissioning in the effective To keep state, the locking member further mechanically in such a way with the hook mechanism of the telephone is coupled that the hanging up of the handset frees the short-circuit contacts from the locked state, while the locking member is further provided with an electromagnet, the activation of which by the electronic Control arrangement also has the consequence that the contacts are released from the locked state,

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In this way, the short-circuit contacts of the telephone according to the invention by using a finger pressure exerted when pressing the first button in the row of buttons pressed when calling. The short-circuit contacts remain locked in their effective state until they are released, either electromagnetically below the control of the electronic control arrangement as soon as the transmission of dialing signals has ended, or manually if the handset is hung up while dialing and the call is interrupted in this way. This becomes an actuation the short-circuit contacts do not require any conductivity, while the capacity required to electromagnetically clear the short-circuit contacts, e.g. on a capacitor which is charged in the time elapsing before signaling, i.e. in the time that elapses between lifting the handset to call and pressing the pushbuttons. So it won't be an expensive one bistable relay with associated protective circuits required. Next is because the short circuit slcon clocks mechanically with the Hook switches are coupled, also no more microswitches required because a short-circuit contact is now used can be used to return the electronic control system to its initial state when the receiver is hung up,

The telephone according to the invention is particularly advantageous if the electronic control arrangement has a memory for storing telephone address information ^:

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contains that by, pressing the pushbuttons in memory is written before the associated dialing signals are broadcast, because in this case at least some the dialing signals are sent while no pushbutton is pressed »

The dialing signals can have any form that corresponds to the requirements set by the associated control center, and they can e.g. from loop interruption impulse series or tone signals consist of series or

[
Parallel multi-frequency signals.

An exemplary embodiment of the invention is explained in more detail below with reference to the drawing, the drawing a block diagram of a telephone according to the invention shows, in which only those parts are shown, which are necessary for a good understanding of the invention.

- The telephone according to the invention shown in the drawing has line connectors 1 and 2 for connection at. a telephone line, an electronic control arrangement 3 * which includes an impulse contact 4, a voice circuit 5 »of which a telephone 6 is a part, a Druckt as tenwählfe Id 7 and a short-circuit contact arrangement 8 contains. The impulse contact 4, the one with this usual symbol is shown, may consist of the contact of an electromagnetic relay, but consists preferably from a transistor switch, the short-circuit contact arrangement 8 contains a

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Umsdialtkontalct unit with spring contacts 11, 12 and 13 »a closing contact unit with spring contacts i4 and 15 ■ and a" breaker contact unit with spring contacts and 17 The spring contact 17 is even further elongated and carries a cylindrical roller 19 at its end. A locking member has at one end a pivot point 21, a hook-shaped projection 22 and a tension spring 23 $ which the member 20 counterclockwise (in the drawing) The usual hook of the telephone is shown at 25 and has an extension rod 26 which can rotate about point 27. The end 28 of the rod rests on the end 24 of the locking member 20 remote from the pivot 21. while a tension spring 29 tries to pull the end against a fixed stop 31. It is assumed that si The hook 25 is in the rest position, ie the receiver is on the hook, so that the end 28 of the rod 26 presses the end 24 of the organ 20 against the pole face of an electromagnet 32 which, via a line, goes through the electronic control arrangement 3 is controlled.

The keypad 7 is provided with a pressure rod 34

provided that when one of the zsbn pushbuttons 35 äes field actuated vrird, after i * real - in the drawing - is moved, so that he also moves the operating rod 18 to the right

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presses. The pressure rod 34 can be a rigid rod, such as is shown, or it can for example consist of a number of balls in a trough.

When the receiver (not shown) is picked up by the hook 25, the spring 29 pulls the end 28 of the rod against the stop 31. The spring 23 simultaneously pulls the end 24 of the organ 20 against the stop 31 , creating a bevel 36 of the projection 22 until Irurz is brought to the role. When the user presses the first pushbutton 35 in field 7 corresponding to the desired telephone address ι the pressure rod 34 pushes the operating rod so far to the right that the roller 19 rolls over the surface 36 , pushing the member 20 up against the action of the spring 23, after which the roller 19 moves past the end of the surface 36, so that the member 20 is pulled down by the spring 23 so far that its end 24 hits the end of the rod 26. The movement of the sedation rod 18 has the consequence that the switch, working and break contacts are actuated via the spring contacts 12, 14 and 17 that are moved onto them. When the pushbutton is released, the roller end of the spring contact remains behind the projection 22 of the organ 20 locked, .so that the mentioned contacts remain in the effective state.

The interruption of the contact between the spring contacts 11 and 12 terminated the short circuit that existed until then on the electronic arrangement 3 of which the

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PP.1149.

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Pulse contact 4 is a part. The spring contacts 12 and 13
short-circuit the speech circuit 5, so that the pulse generation circuit exclusively from the pulse contact h ^;

exists between terminals 1 and 2. The spring contacts i4
and 15 close the telephone 6 directly via its j

Terminate briefly so that no inductive pulses are generated when generating pulses Click from the telephone picked up «The spring contacts 16 and 17 end the previously existing Eurz-

Closure of the reset inputs of the electronic control;

ι;

arrangement 3 »so that you 'now on the from field 7 over the;

j line 37 can address information received. The elec-!

tronic control arrangement 3 is now in series;

with the telephone line and will be on the familiar T7eise j fed by the line current,

If all stored digits of the called;

Telephone address are sent, sends the electronic ι

j control arrangement 3 on line 33 an impulse to initiate

j driving the electromagnet 32, as a result of which the end 2k j of the organ 20 is attracted by the pole face of the electromagnet, so that it is the one shown in the drawing
Takes position. The roller 19 and the end of the spring contact 17 are behind from the locking position
dem.End of the projection 22 of the organ 20 frees what to
The result is that the contact arrangements consisting of the spring contacts 11 to 17 are in the rest position shown
to be led back. The pulse by which the electromagnet 32 j

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± 11 operation is set, is only of such a duration that it unlocks; the roller 19 allows, and its performance need only be low, because the friction to be overcome is low. In a practical embodiment, a pulse with a power of 100 rv.-I and a duration of 5 ms was used, which was tapped from a capacitor of 22 / uF, which had previously been charged up to 10 V. The spring contacts 11 and 12 short-circuit the impulse contact. The short circuit across the. Telephone 6 and via the speech circuit 5 is eliminated, while the electronic control arrangement is returned to the initial position because the spring contacts 16 and 17 come into contact with one another. The call continues in the usual manner. At the end of the call, the user puts the handset back on the hook 25 and the rod 26 returns to the position shown in the drawing.

If when choosing the KSrer again on the hook 25 is placed or the tick is pressed to end the (no longer wanted) call is thereby activated triggered movement of the rod 26 of the projection 22 of the organ 22 upwards and return the contact arrangements back to the rest position in the manner described above, whereby the electronic control arrangement the starting position resumes so that the telephone is ready to start a new call. It should be noted that the changeover contact arrangement, those from the spring contacts 11, 12 and 13

409881/0976

exists, a work-before-break contact arrangement can be, which has the advantage that the "click" be reduced in the recipient *

Keypads with a push rod that is put into operation when any push button is pressed are known per se. The electronic control arrangement 3 can, for example, be of the type which contains a memory in which a telephone address written via the pushbuttons is stored before the associated dialing signals are sent out. Such devices are described, for example, in British patent specification 1 195 ik \ .

It will be apparent to one skilled in the art that many other mechanisms are conceivable that perform the same function as the can meet the short-circuit contact arrangement 8 ″ shown in the exemplary embodiment described, and the invention is limited therefore does not relate to the embodiment described. For example, the locking arrangement can be connected directly to the rod 18 instead of via an extension piece of the spring 17 work together.

Although the invention has been described in terms of an embodiment in which loop break line signals can be generated by pressing the pushbuttons, as mentioned above, it can be used just as well for other signaling types (e.g. tone signaling), and the type of signaling used is therefore exclusively through “You determine the electronic control arrangement 3 without this affecting the rest of the circuit, except in certain Other contact combinations in the short-circuit contact order 8 may be required.

A09881 / 0S7P

Claims (1)

PATENT CLAIM: T, Keypad Fernspreclier with an electronic control arrangement (3) for generating '.,'"Hl signals by actuating the pushbuttons {35) and with electrical short-circuit contacts (11-I7)» which are mechanically coupled to the pushbuttons (35) in such a way that they be put into operation upon actuation of any pushbutton, characterized in that a locking element (20) is arranged in order to keep the short-circuit contacts (11-17) in the operative state after the activation, the locking element (20) further mechanically in this way the hook mechanism (26) of the telephone is coupled, so that when you hang up the receiver, the short-circuit contacts (11-17) are released from the locked state, while the locked treatment organ (20) further with an electromagnet (32) ver-1 ^{can be seen, which frees the contacts (11-17) a} U-5 from the locked state when excited by the electronic control arrangement (3). 40988 1/0976