DE1242273B - Circuit arrangement to prevent double assignments in automatic switching systems - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY GERMAN WWW PATENT OFFICE Int. Cl .:

H04m

EDITORIAL

H04g
German class: 21 a3 - 28/01

Number: 1242273

File number: C 31455 VIII a / 21 a3

Filing date: November 18, 1963

Open date: June 15, 1967

The invention relates to a circuit arrangement for preventing double assignments in automatic switching systems, in particular telephone switching systems with two different built-up and independently working dialing systems on one or more can examine joint organs and have such predetermined time-based examination conditions, that at a certain time of confirmation the intrusion of one system to the checked one Organ can no longer be prevented by a locking process of the other system.

In the usual test multiple circuits, in which the blocking, for example, by a contact is effected, double assignments are not completely ruled out; one is only looking for its probability to keep it as small as possible. Within the time until the blocking contact closes elapses, a further test relay can also pick up, so that a double assignment occurs comes.

There are numerous circuit arrangements to prevent such duplication within of the same dialing system known. In most of these circuit arrangements there are control elements, For example, differential relays, bridge circuits or the like. Provided that with a double occupancy address and give priority to one of the two examining bodies. The switching relays are delayed so that the connection only takes place after completion of this test process. pre-condition it is, however, that the control members are accessible from and by all examining organs can be influenced in the same way.

However, these known circuit arrangements are not suitable if the problem is Double occupancy of a common organ by two or more independently working and possibly to prevent differently structured dialing systems. For example, this problem arises if there is a further PBX in addition to an existing PBX other type is added and both PBXs are checking for the same trunks should. In this case it is not possible to establish cross connections between individual organs of the two dialing systems and common control members, quite apart from the fact that at Different structure of the two dialing systems have a similar influence on a common one Control body is not possible. For example, a dial system and a rotary dial system Circuit arrangement for prevention

of double assignments

with automatic switching systems

Applicant:

CIT Compagnie Industrielle
des Telecommunications, Paris

Representative:

Dipl.-Ing. E. Prince,

Dr. rer. nat. G. Hauser

and Dipl.-Ing. G. Leiser, patent attorneys,

Munich-Pasing, Ernsbergerstr. 19th

Named as inventor:
Henri Lefort,

Verrieres-Le-Buisson, Seine-et-Oise
(France)

Claimed priority:

France of November 19, 1962 (915 867)

the other dialing system can be a crossbar dialing system.

In such cases a mutual influence of the two dialing systems is only about the to the common organ leading test leads possible. A locking process is prescribed for each dialing system, by which the activation of this dialing system is prevented. Apply to everyone Dialing system the following time test conditions: After the start of the test there are a specific point in time (hereinafter referred to as the "confirmation time") for which the following applies: If the corresponding blocking process is created before this confirmation time, there will be no intrusion instead of; However, if the blocking process is only created after this confirmation time, intrusion can no longer be prevented, even if it was at the time the locking process was created was not finished yet. The distance between the confirmation time of a dialing system and the The beginning of the test process can easily be determined by measurements.

The aim of the invention is to create a circuit arrangement which, even under these conditions,

709 590/65

prevents double assignments of a common organ with complete certainty, even if the dialing systems checking for this system are constructed completely differently.

According to the invention, this is achieved in that a locking member is provided for each system, that after the start of the test process in a blocking time the blocking process to the other system creates, and that the locking members of the two systems are designed so that at least one of the In both systems, the blocking time is before the confirmation time and the distance between the two The times in the system with the confirmation time before the lock time may be smaller than with the other system.

In the circuit arrangement according to the invention, double assignments are made possible by a suitable choice of Prevents times in which the blocking body of an inspecting system after the start of the Check process creates the lock process for the other system. After the location of the confirmation time is determined by measurement for each system, it is always possible to design the locking devices in such a way that that the previously specified conditions for the blocking times are met. In some cases it is also possible to postpone the confirmation time within certain limits, whereby the Compliance with the specified conditions is made even easier.

Each dialing system works exclusively according to its own structure and working principle regardless of the type of the other existing ones Dialing systems. Nevertheless, double assignments are certainly also in such cases excluded, in which extremely different temporal test conditions prevail, for example when combining a slow rotary selector system with an electronic system,

The invention is explained by way of example with reference to the drawing. In it shows

F i g. 1 a simplified block diagram to explain the problem to be solved,

F i g. 2 a timing diagram of a test circuit,

F i g. 3 shows a timing diagram of a test circuit,

4 shows an embodiment of a test circuit in a known system,

F i g. 5 shows a diagram of the mutual blocking of two test circuits,

6, 7, 8, 9 are diagrams showing the mutual blocking of two test circuits in different relative positions,

F ΐ g. 10 is a diagram for explaining the problem of double checking;

F i g. 11 a solution according to the invention for the example shown in FIG. 10,

F i g. 12 a second example of the double check problem and

F i g. 13 shows a solution according to the invention for the example shown in FIG.

F i g. Figure 1 shows two circuit channels belonging to two different telephone systems. The organ A closes the first switching channel, the organ B closes the second switching channel, and each of the organs A and B , independently of the other, has access to a common organ C. It is a matter of any double connection (and in general to prevent any multiple connection) of the organs in front of A and B with the common organ C. It can be assumed that the organs belonging to the same system already contain their own devices which prevent any such double connection among themselves; the same applies to organs B. There is the problem of determining which mutual relationships must exist in organ C between organs A and B so that any double connection is made impossible. It is sawn known that each of the institutions A and B prior to the preparation of a compound with the organ C checks the organ C, to determine its idle or busy condition. The operation of a test circuit takes place for a given system and for a given selection level in a time span which always remains very largely the same and which can therefore be regarded as constant.

Fig.2 shows a diagram, the axis of which is time represents. The operation of the a

Points in time that characterize the arrangement are thus represented by corresponding points on this axis. If, for example, the system containing the organs is considered, its origin A ₀ can appear at any point in time, and

The end A ₁ appears a certain time later, but the distance A ₀ A ₁ , which represents the duration of the normal process without external disturbance, is constant. For any telephone system to which organ A or organ B belongs, however, there is a point C ^ which lies between A ₀ and A _f and the abscissa of which is completely fixed with respect to A ₀ , in such a way that

each operation of blocking of A phenomenon which occurs between ₀ A and C _A, interrupts the operation of A;

any occurrence blocking the operation of A , which occurs at a point in time between C _A and A ₁ , has no effect on A's operation.

The point C _A is therefore a critical point, which corresponds to the test confirmation. The location of this point C _A depends on the one hand on the internal test process peculiar to the system under consideration and on the other hand on the type of effect of the blocking phenomenon. Knowledge of point C _A is necessary and experimental measurements must be carried out in every telephone system to which organs A or B belong in order to determine the duration of the period A ₀ C _A. As a result of the spread of the operating properties, the state of the test circuit, which basically occurs at time C _A , can in reality arise during a certain period of time which lies within the limits C / and C / ' (Pig. 3), so that the duration A ₀ C _{A can be contained} between a minimum A ₀ C / and a maximum Α _ϋ C _a " .

In order for the above definitions to be concretized by the example, FIG. 4 shows a partial representation of the test circuit and the connection stage of a selector in the automatic telephone system known under the designation "R6". As is known, in such a system the selector contains a contact arm ST which triggers a relay 11 with two windings as soon as it arrives at a row of contacts which is marked by a direction indicator, not shown (in the case of the system R 6

is referred to as a directional organ shared by several voters, which controls the setting of the voters in the desired directions.) The excitation circuit of the relay 11 runs from the negative pole of a battery (not shown) via a resistor R ₂ , the contact 1 of the selector contact bank, the Contact arm ST of the selector, the two series-connected windings of the relay 11, a working contact 122 of a differential relay 12, which has previously been excited at its lower winding via a resistor R ₁ from the same battery, to ground. The relay 11 then breaks at 111 the control circuit for the rotation of the selector. The point in time at which the contact arm of the voter reaches the contacts marked by the direction indicator is shown in the diagram of FIG. 3 at A ₀ . Closing contact 112 also energizes the top winding of relay 12. If there is no double check, the ampere-turns generated by this upper winding will compensate for the ampere-turns generated by the lower winding, so that the relay 12 drops out. The selector also contains a so-called stage connection relay 13, which is then excited via the following circuit: ground, normally closed contact 121, normally open contact 113, upper winding of relay 13. As soon as relay 13 has closed its contact 131, it holds itself via the following circuit: Battery, upper winding of relay 13, normally open contact 131, ground, via other contacts, not shown. This point in time is shown in the diagram of FIG. 3 represented by the point A _f . As can already be seen, the test confirmation time C _A depends on the type of disturbing phenomenon. It is assumed that the selector is mechanically blocked in position 1 and that the circuit of the resistor R _{2 is opened} at a point H by the normally open contact of a relay, not shown. With the help of calibrated pulses of variable duration, this relay is energized, which then closes its normally open contact for a known time. The moment at which this normally open contact closes corresponds to point A ₀ in FIG. 3.

The time at which the normally open contact of this relay opens at the end of a pulse corresponds to the effect of a blocking phenomenon that interrupts the test circuit. After a series of attempts, a time span can be determined, which is the largest time span in which the relay 13 cannot hold itself. This time span ^ ₁ determines the smallest distance A ₀ C _A. In the same way, a period of time t _{2 is determined} , which is the smallest period of time in which the relay 13 can be latched. This time span i ₂ corresponds to the greatest distance A ₀ C _A (FIG. 3). The path C _A 'C _A " is the" test confirmation path ". Instead of opening the test circuit with an interrupt contact, it would of course also be possible to apply ground to point H , which would short-circuit the test relay 11; then one would get another smallest path A ₀ C _A and also a different longest distance A ₀ C _A than before. The new test confirmation path would lie further to the left than the previously determined path, which is understandable due to the additional effects of electromagnetic inertia. In practice, every test confirmation path is otherwise tiny.

F i g. 5 shows a diagram for the mutual locking of two test circuits. The Prüfbestätigungsstrecke C _A, which is limited as in Figure 3 by two points C / and C _A ', part of the organ A, and the Prüfbestätigungsstrecke C _B, which in a corresponding manner is limited by two points C _B and C _B " belongs to organ B. In organ B there is a locking device which prevents the organ ^ from being checked. This facility occurs in one

ίο Time / _B in action. In the same way, there is a blocking device in organ A which prevents organ B from being checked and which appears at a point in time. Thus, in the organ , the blocking device originating from organ B appears at a point in time I _B , which can be before or after the test _{confirmation time interval C 4} . If the corresponding point I _{B is to the} left of C _A , the operation of the test circuit of organ A is interrupted. If I _{B is to the} right of C _A , the operation of the test circuit of organ A is not disturbed. In the same way, in organ B, the blocking device coming from the organ comes into operation at a point in time that can be before or after the test confirmation time interval C _B. If the corresponding point I _{A is to the} left of C ₈ , the operation of the test circuit of organ B is interrupted. On the other hand , if I _{A is to the} right of C _B , the operation of the test circuit of organ B is not disrupted. Thus, only the relative positions of the points I _B and C _A 'C _A " are sufficient to determine the action of the organ B on the organ A. In a corresponding manner, the relative positions of the points I _A and Cβ'Cß" alone are sufficient to determine the action of organ A to organ B. Now, however, the position of point I _A in relation to C _{A is} known, and the position of point I _B in relation to C _{B is also} known. Practically l _A C _A pos be itiv or negative, and the same applies to I _B C _B. The investigation of the systems to which organs A and B belong, as well as their blocking connections, can therefore be traced back to a consideration of the dimensions and the relative positions of the lines I ₁ C _A and I _B C _B. Eight cases exhaust all operational hypotheses; however, for reasons of symmetry, the problem can be limited to the following four cases.
It is initially assumed:

\ i _A c _A \> \ i _B c _B \

With this assumption one can have the following cases:

I _B C

_B C _B I _B C _B I _B C _B I _B C _B

0 0 0 0

1. 1 _A C _A > 0

2. I _A C _A > 0

3. I _A € _Ä < 0

4. I _A C _A <0

First case (Fig. 6)
I _A C _A > 0 _BB

Regardless of the relative positions of the routes I _A C _A and I _B C _B on a time scale, the blocking time of one system always precedes the test confirmation time of the other system. So there is never a double connection.

Second case (Fig. 7)

IaCa > 0 I _B C _B < 0

I _B C _B > 0

As in the previous case, the lock time of one system is always before the test confirmation time of the other system. So there is never a double connection.

Third case (Fig. 8)

IbCb> 0

It can be seen that there is no blocking time and a test confirmation time in the case of the two shown Opportunities ahead. So a double connection is possible.

Fourth case (Fig. 9)

IaCa < 0

IrC ₈ < 0

It can be seen that there is no blocking time and a test confirmation time in the case of the two shown Opportunities ahead. So there is the possibility of a double connection.

From the investigation of these four cases it appears that any double connection is impossible if one of the following two conditions is met:

First condition

In both systems, the blocking time is before the test confirmation time.

Second condition

If the blocking time in one of the systems is after the test confirmation time,

a) In the other system, the blocking time must be before the test confirmation time;

b) the period of time between the test confirmation time and the lock time in the first system, must be less than the time between the lock time and the test confirmation time is in the other system.

These conditions can be symbolically written as follows:

First condition:

(/ C) ₁ > 0 (/ C) ₂ > 0

Second condition:

(CI) ₁ <(IC) ₂
or

(CI) ₂ <(IC) ₁

Two application examples for the above conditions will now be given, with one example relates to the first condition and the other example to the second condition. F i g. Fig. 10 schematically shows a particular problem in the extension of a telephone exchange of the System type R 6. This exchange contains selection stages, which are very schematically shown in the drawing a rotary selector 14 are shown, and it is expanded by a system, which is shown schematically at 15 shown selection levels of the type known under the designation System CP 400 contains. The selection levels Both systems have arbitrary access to an "outgoing connector" 16 of the R 6 type. A line distributor, which is indicated schematically at 17, is located behind the connector 16. One of the Difficulties to be overcome with such a system concern the double examination; Fig. 11 shows an arrangement embodied in accordance with the invention, in which the aforementioned conditions are fulfilled.

In the arrangement of FIG. 11, the device according to the invention is added to the arrangement of FIG. Three zones are delimited by dash-dotted lines: A zone (I) contains the selector stage 14 of the R 6 system, a zone (II) contains the selector stage 15 of the CP 400 system, and a zone (III) contains the common connector 16, which is used here is carried out in the system R 6; however, only the test circles are shown. The common connector 16 contains two separate test leads which are connected to the selector stage 14 and the selector stage 15, respectively. The test circuit of the selector stage 14 contains relays 11, 12 and K ₁ , and the test circuit of the selector stage 15 contains

zo relays T ₀ and K ₂ . The relays K ₁ and K ₂ are the blocking relays: When the relay K _{2 is} energized, it interrupts the test circuit of the _{with its contact Ir 2}

~ _{v and vice versa, the ReIaJsX 1} interrupts the test when it is excited with its contact k _x

circuit of relay K ₂ . The test is just as good in "homogeneous" operation, in which only the organs of zones I and III or zones II and III come into operation, as in "mixed" operation, in which the organs of zones I, II and III come into operation because the elements of the audit groups of the organs of zones I and II are unchanged. In order to prevent any double connection in the case of a double test, the blocking relay corresponding to one of the telephone systems must be triggered before the test confirmation time occurs. For this purpose, the part of the connector 16 assigned to the selector stage 14 contains resistors 18 and 20a, the order formed from these resistors and the relay K ₁ having to be such that, during the homogeneous test process, one or more organs can be operated of the Zone I system. Likewise, the part of the connector 16 associated with the selector stage 15 contains resistors 19 and 20 b, the arrangement formed from these resistors and the relay K ₂ must be such that it can operate one or more organs of the system of the homogeneous test process Zone II not obstructed. In the application example shown, these conditions are met in that so-called "sensitive" relays are used for the relays ^ and K _2. After the type of effect of the blocking has been defined, it is possible to determine the test confirmation times in each system, which are fully defined: For the system of zone I (type R 6), the test confirmation time is defined by the non-response of relay 13 of the selector and for the Zone II system (CP 400) due to the failure of the TD ₂ relay to respond.

Referring to the diagram of FIG. 2 one finds:

For the system R 6 A ₀ C _A = 37 ms

For the system CP400 ... B ₀ C _B = 33 ms

The periods of time which lie between the original times A ₀ , B ₀ on the one hand and the corresponding blocking times I _A , I _B on the other hand are

9 10

the response delay of the relay K ₁ or bene problem solves. The outgoing connector 24 becomes

K _{2 the} same. One finds: from the output stage of the CP 400 system

For the system R 6 A ₆ I _A = 20 ms ( ^{on the} f ^a circuit arrangement ^{not shown)}

, """..""τ,, * ~ only marked if the signpost

For the system CP 400 ... B ₀ I _B = 19 ms _{g and the system selector of type R6 are free}

Referring to FIG. 6 one obtains: The test is divided into two separate phases:

V Hn «Svctpm T? fi first it is checked by an internal exclusion

rur aas oysiem ^ o ^ _ng ^ _{system cp 400 allows) that only one a} _

Iaca ⁼ A ₀ C _A - A ₀ I _A = 37 - 20 = 17 The ms _{z e} ig r connector from the same direction for the system CP 400 ^{10 we} i ^ser dependent connectors is selected, and r - R r R7- -3Q IQ - i / i then (and that is the subject of the description) Iβ C β -B ₀ C ₃ - B ₀ I _B - 33 - 19 - 14 ms _{does the} marked connector perform a second test. that both for the SystemR6 fungus. In Fig. 13, two applies schematically to as well as for the CP 400 system: test circles belonging to the same direction are shown.

15, one of which goes through voter 26

IaCa ·> 0 _{un (} j ^ m selector 23 belongs, while the other ^{goes over and} the selector 27 and belongs to connector 24. IßCß -> O JJi _n relay 29 takes over the role in connector 24. The two systems thus correspond to those previously ., test relay the homogeneous double testing entangegebenen conditions, since the first condition 20 is not satisfied result 400 in the R 6 or in the system CP can no double connection arise no particular difficulties. they are the special case according For that the relay X ₁ and K ₂ of the usual principles in the system R 6 or of the same type and their break contacts at the same time the aid of an additional arrangement that prevents opening (simultaneous points /), but more than one connector can arise for each directional oscillation state 25 is selected, carried out in the CP 400 system, are never materially identical, this appearance disappears quickly If, however, an R6-type voter and a delay-type connector result in the occurrence of the point /, the CP 400 will be discussed below.
Appearance survived (so-called "privileged" relay 29 of connector 24 responds if point /). The point C of the blocked system can lead the line T _{B to} the correct potential, which then appears before the point /. Then a free state of the selector 27 and the directional double connection would be possible; to prevent them, sers is marked 28; this is done via the contact m (the test area is long enough so that the points C in the ginnrelais m is not shown in the drawing) that the lines I _A C _A and I _B C _{B must be in} working condition Special case never before the points / are 35 The changeover contact 291 leaves the rest position. and shortly afterwards goes into the working position. As soon as a further application example has been opened, the rest side of the contact 291 is now to be written, in which the second condition thus the relay 29 has a self-holding circuit is fulfilled, which was previously indicated by the symbolic writing resistor 30, which with the negative pole of the way 40 battery is connected, and through the grounded / ■ ^ λ ^ - q _c · ^ going contact 291 a busy * ■ 'i \ h potential is then placed on the line T _B. It has been formulated to recognize. In this case, one of the NEN is that the ground potential system on the line T _B of the form CI and the other of the tial has the effect that the test relay 11 of the Form / C. 45 selector 23 is short-circuited. Since it can happen, for example, in a mediation of, on the one hand, the internal test process of the system R 6, type R 6, that selector of the type R 6 and, on the other hand, the type of action of the blocking connector of the type CP 400 access to an appearance ( Short circuit of the coil of the test relay) have a common circuit channel. Such an approach is known, it is possible, experimentally, the test position is shown schematically in FIG. 12 shown. The confirmation times C _{A of} the organ of the R 6 type, mediating organs of the R 6 type are ^to be determined in a dashed line.

The dotted frame 21 is shown, and the reverse, the action of the system R 6 management organs of the type CP 400 are shown in a dashed line on the system CP 400 in the following way: If the dotted frame 22 is shown. The system R 6 contains one or more of the test relays 11 and 12 of the type holding selectors 23, 26, 27, and the system CP 400 contains 55 R 6 that are already connected to the point β, can hold connectors 24. The two Systems do not have to be energized to relay 29 because the line has common outputs 25. The T _B does not have the right potential. The test confirmation selector 23 have access to certain selectors 26, the time C _B of the CP 400 organ is activated, and the connectors 24 have access to others, i.e. by delaying the opening of the idle selector 27, but the selectors 26 and the 60 side of contact 291 of relay 29 is determined.
Voters 27 of common direction signs 28 One finds ¹
controlled so that this is not provided separately

must be. In order for such an organization to need- For the system R6 A ₀ C _A = 33 ms

cash, it is obviously necessary to double _{For the s tem cp 400 BC = 6? ms}

bmdungen about the same direction indicator to sell 65 ^{J u}

Offer. On the other hand, since the relay 29 does not respond

FIG. 13 shows a configuration according to the invention when a relay of the R6 type is connected in parallel to it

led arrangement, which is connected to the resistance of the direction indicator indicated in Fig. 12,

IaCa -

¹ A

= 33 - 0 = 33

This means that the blocking time of the system R 6 appears simultaneously with the start of the test, so that A ₀ I _A = 0. In the CP 400 system, the test of the system R 6 is prevented by applying ground potential to the common point Q . The blocking time of this system is characterized by the delay in closing the working side of contact 291 of relay 29.

One finds:

ß _o 7 _s = 73 ms
The following sections are obtained:

10

I _B C _B = S _O C _S - B ₀ I _B = 67 - 73 = -6

It should be noted that the system R 6 has the form IC > O, while the system CP 400 has the form IC <O, that is, CI > 0. So the following applies:

Since this result agrees with the formula of the second condition, the arrangement must be correct work.

It can be seen that in the arrangement according to the invention, the test confirmation time of the the actual test setup of the system in question and the type of blocking chosen; the arrangement according to the invention must be adapted to the problem to be solved in each case.

The invention is of course not limited to the two application examples given above, but which have been chosen so that they meet the two types of conditions with regard to the Routes 7C are met.

The arrangement according to the invention is of course also applicable when the two of each other independent systems are separated from each other, in automatic telephone systems, for example when they are not in the same office, so that some resistance between the blocking device of the remote system and the common one in the same office as the other system Organ is inserted.

Furthermore, the invention is also applicable when the same in one of the telephone systems Relay for testing and blocking is used, while the test relay is used in the other telephone system and the locking relay are disconnected.

In the above description, some special types of action of the blocking relay have been identified the test relay of the other system is specified (opening of the test circuit, operation of a test relay under Boundary conditions, short circuit of the coil of a test

35 relays), but other types of magnetic, electrical or mechanical locking can also be used.

Claims (5)

Patent claims: 1. Circuit arrangement to prevent double assignments in automatic switching systems, in particular telephone switching systems with two differently structured and independently working dialing systems, which can check for one or more common organs and have such predetermined time test conditions that the activation of one system at a certain time of confirmation the checked organ can no longer be prevented by a blocking process of the other system, characterized in that a blocking organ (e.g. K ₁ , K ₂ ) is provided for each system, which after the start of the testing process at a blocking time (7) the blocking process to the creates another system, and that the locking organs of the two systems are designed so that the locking time (/) is before the confirmation time (C) in at least one of the two systems and the interval between the two times (7, C), if necessary, in the system the confirmation time point (C) before the blocking time (7) is smaller than with the other system. 2. Circuit arrangement according to claim 1, characterized in that the locking members of the Both systems are locking relays that are added to each system. 3. Circuit arrangement according to claim 1, characterized in that the locking member of the one system is a blocking relay added to the system and that the blocking element of the other System is the test relay of this system. 4. Circuit arrangement according to one of claims 1 to 3, characterized in that the Blocking device of one system the response of the test relay of the other system by short circuit of the test relay prevented. 5. Circuit arrangement according to one of claims 1 to 3, characterized in that the Blocking device of one system triggers the test relay of the other system by interrupting it of the test relay circuit prevented. Considered publications:
German Auslegeschrifts No. 1120 512,
702, 1021078, 1030 886, 1036325,
889, 1119 921. 1 sheet of drawings 709 590/6? 6.67 © Bundesdruckerei Berlin