DE575916C - Circuit arrangement for telephone dialers, in which two-wire connecting lines are selected by three-wire dialers - Google Patents

Description

The invention relates to three-wire set up voters, the two-wire in free choice Select connecting lines. According to known requirements, the occupancy of the lines should not only be free of them, but at the same time on their operational condition as well as on the operational readiness depend on the switching devices connected to the incoming end of the lines.

If necessary, a connection line should be created by means of a simple switching measure, ζ. Β. Interruption that can be artificially blocked from the incoming side.

In the previous circuits, the aforementioned requirement is through a single The test process is sufficient by placing a test circuit over the one emerging from the selector third line wire and the coupled speech line is formed. This arrangement

However, ao tion makes switchovers and at the beginning and at the end of the line seizure the use of special relays and contacts in the connecting lines is necessary.

In order to avoid the aforementioned disadvantage, in the invention of one at three-wire connecting lines known circuit proposal, which for the determination the occupancy state and the operational state of a connecting line separately in time provides for successive checking, made use of in a modified manner. While in the well-known example for double testing switching means (relays and contacts) are in turn provided in the connecting lines, according to the invention by a specific design of the circuits for double testing, the switching means are completely removed from the area of the connecting lines removed and relocated back to the voters upstream of the connecting lines. The modified facility results in a much simpler formwork arrangement for two-core connecting cables than before (only one relay more than usual) and at the same time allows all to operate connecting lines outgoing from the voters uniformly two-wire.

The invention is explained in the drawing using an exemplary embodiment in which Interruptions in the connection lines, which represent the most interesting case, were assumed to be the source of interference are. The inclusion of other sources of interference, such as B. Earth fault and connection line, it follows by itself.

The drawing shows a voter office with pre-selectors and first group voters, from which from a second voter office with a second via two-wire connecting lines Group voters and line voters

is rich. There are only the current paths necessary for understanding the invention shown.

If the calling subscriber JV ₁ unhooks his S handset, then he will use a preselector VW with a free first group selector /. GW connected. Relay / responds there. The first group selector is set to the desired decade ίο in a known manner. After the stroke movement, a contact χ closes the interrupter circuit for the rotary magnet D · of the first group selector to select a free connection line. As long as the calling subscriber is connected to the first group selector, a relay V I is energized via Z ₁ . By the rotational movement of the first group selector of the rotary magnet Z> is a delay relay V is energized via a normally open contact · ά laying on the test relay ν P to check for free or Besetztsein the connecting line to the c-wire. As soon as the switching arms of the first group selector hit a free connection line, relay P responds (- {-, ν 13, ν, P ₁ C, W ₁ -) and stops the rotary magnet through / J _1. Two cases are now possible:

i. The connection line found free is disrupted. At p _2, test relay P connects a second test relay Q in a bridge in the speech wires of the connection line. If the line itself is interrupted or if the fuse has been removed at the incoming end of the line for any reason, relay Q cannot respond. By stopping the rotary solenoid at P ₁ , relay V drops with a delay and interrupts the test circuit for P. As a result, p _x is closed again and the rotary solenoid continues to rotate until the switching arms find a new free connection line.

2. The connection line found free is not disturbed: The test relay Q connected to the speech wire by p ₂ in a bridge responds to {- \ -, B ^r in the second group selector, p {, b wire, arm b ', p ₂ , Q, Arm d, α-wire, p ₂ , A ' in the second group selector, -) and switches the line through at q ₂ and q _s. As before, relay V drops out with a delay and interrupts the circuit for test relay P. However, the circuit for rotary magnet D of the group selector remains open at q _x. Relays A and B respond in the first group selector and apply occupancy potential to the c wire via b and the low-resistance winding of relay Q. By opening p ₂ the bridge is removed from the speech wires of the connecting line.

Together with Q ₁ A ₁ and B in the first group selector, relays A and B 'of the second group selector respond. The setting of this to the desired line group is done by interrupting the current of the «wires by means of the impulse contact 12 in the first group selector. The relay A 'of the second group selector transmits the current impulses to the lifting magnet H', and during the lifting movement the relay V II is energized, which closes the interrupter circuit for the rotary magnet to select a free line after the lifting movement has ended. As soon as a free line is found, test relay P ' responds and stops the selector. P switches through at p ₂ ' and p ₃ ' , and relays A " and B" are energized in the line selector. The line selector is also set in a manner known per se. A relay V II (not shown) which is excited during the setting closes the circuit for the test relay P " after the selector has been shut down via v 'II.

During the call, a direct current flows through each voice wire of the connecting line from relay A ₁ B in the first group selector to relays A ', B' in the line selector. As a result, the voice wires can be used individually for different switching operations. For example, by responding to Y in the line selector LW when reporting the desired subscriber at point X ₁ in the line selector, the α-wire can be briefly interrupted and caused by the short-term de-excitation of relay A in /. GW an influence on the counter can be effected. . • If the called subscriber hangs up first, the falling relay Y at x ₂ can interrupt the current for relay B " in the line selector and relay B in the first group selector. Relays P" are dropped in line selector too and in the second group selector. and P ' from. Relay Q is de-energized in the first group selector. Closing p ₅ ' in the second group selector triggers the second group selector. Only when the caller hangs up is the first group selector relay V I de-energized by dropping the relay /, which causes the first group selector to be triggered by closing the contact ν I 2 and the return of the preselector by opening the contact ν 11.

Claims (2)

Patent claims: i. Circuit arrangement for telephone exchanges, in which two-core connecting lines are set up by three-core Voters are selected because ^ characterized in that two laterally successive test processes which ' separately the determination of the occupancy rate. Status and operational condition serve for connecting lines and only allow a line to be occupied if both tests fail successfully, in the voters upstream of the connecting lines come about in such a way that the first test process, which is locally limited via a special test line, when a line is found in the searching voter (J. GW ) closes the second test circuit formed via the voice wires and the remote switching point (TI. GW) and, if the second test fails, initiates the connection of the selector to the connection line and the blocking of the same. 2. Circuit arrangement according to claim i, characterized in that the voter, if the second check procedure the occupancy of the found free Line does not allow, for the purpose of renewed testing of lines far he switches. 1 sheet of drawings