DE562524C - Electrical signal system for railways etc. like - Google Patents

Description

GERMAN EMPIRE

ISSUED ON
OCTOBER 26, 1932

REICH PATENT OFFICE

PATENT LETTERING

CLASS 2Oi GROUP

Patented in the German Empire on October 21, 1931

is used.

The invention relates to rail signal systems for railways and the like soft the tracks, which are divided into block sections, serve as a ladder and in sections are connected to a signal power source and a relay.

In the known systems of this type, the power source, which is an alternating current, is a Can be direct current or a rectified or pulsating current in one direction, connected to the rails at one end of the block section while the relay either directly or through a rectifier at the opposite end of the

»5 section is connected to the track rails.

According to the main feature of the invention, the rail circuit is designed so that he with an AC power source and a relay at one end of the track circuit and a rectifier connected at the other end thereof, the rectifier causes the current flowing through the relay to be the same under normal conditions Maintains direction.

The invention is illustrated by the drawings. Figs. 1, 2, 3 and 4 show schematic views of signal systems for track circuits with different embodiments the invention.

In these drawings, the rails of a railroad track are indicated at 1 and 2 and divided by isolated joints 3 to form a block section AB . At one end of this section there is a transformer T, the primary winding 4 of which is supplied with alternating current from a current source (not shown).

In the system shown in FIG. 1, a direct current relay C is now provided at the same end of the section AB where the transformer T is located, the field winding of which is connected to the rails 1, 2. The secondary winding 5 of the transformer T is also connected to the rails 1, 2, possibly in series with an impedance E. The impedance E is drawn as a non-inductive resistor, although under certain circumstances it can also be a capacitor. In cases where the device £ is a non-inductive resistor, it preferably has an ohmic value at least equal to that of the resistance of the winding of the relay C,

At the other end of the section AB there is a rectifier D, which is also connected to the rails 1 and 2.

If there is no train or vehicle on section AB , the electromotive force that is pressed on rails i, 2 by secondary winding S of transformer T causes the direct current circuit to flow through in one direction ίο in which the rectifier! ? is permeable. Then the current is short-circuited via the rectifier, and the relay C receives practically no current. If the direction of the current changes, the electrical connection of the tracks is canceled due to the blocking effect of the rectifier D , so that the current mainly flows through the winding of the relay C.

If a train or vehicle steps on section AB, the rails are short-circuited and relay C is de-energized.

In order to reduce the losses in the magnetic circuit of the relay C , it is desirable that the magnetic core of the relay is lamelas lated, and for the same reason an inductance or choke coil 6 or rectifier can be included in the relay circuit, as shown in FIG .

A track circuit constructed in accordance with the invention has unusually high sensitivity. For example, on a track circuit 170 m in length, the track relay C will trip at a shunt value of 6.7 ohms across the rails, while a DC track circuit of the usual type and of the same length, which contains a two-volt battery, requires a shunt value of 2.58 ohms cause the relay to trip.

Another advantage of a track circuit according to the invention is that the power source and the track relay can be arranged in the same place. This is particularly desirable where a path crossing signal has passed through a track circuit monitored and AC power is only available at the intersection. Usually in such systems Collector battery track circuits are provided and it is necessary to power lines from the To relocate the crossing point to the extreme ends of the monitoring track circuits, to charge the batteries. Of course, if track AC circuits are used under the same conditions, power lines must be used also be laid from the crossing point to the distant ends of the monitoring track circuits.

In the modified system according to FIG. 3, the excitation winding of the relay C is connected in series with the secondary winding 5 of the transformer T instead of in parallel with it as in the systems of FIGS. 1 and 2. A resistor 7 is connected in parallel with the relay winding. This resistor 7 is provided for the purpose that the electromotive force which is pressed on the rails 1, 2 by the secondary winding 5 of the transformer T is of sufficient magnitude to ensure the effective operation of the rectifier D. In the system according to FIG. 3, as can be seen, the winding of the relay C is excited by the uniformly flowing pulsating current which flows through the rectifier D in the direction of its low resistance.

In the system according to FIG. 4, two rectifiers D ¹ and D ^{2 are arranged} opposite to one another at one end of the track section AB , one or the other of these rectifiers D ¹ , D- is arranged so that it is arranged across the rails 1, 2 is switched, depending on whether a control relay R is energized or de-energized.

The relay C at the opposite end of the track section is a polarized one, and the excitation winding of the control relay R is switched across the rails of the track section BF, which abuts the section AB , with the direction of train traffic going over the sections AB, BF through the Arrow is indicated.

The mode of operation of this embodiment of the invention is as follows:

If there is no train or vehicle on the section BF , the relay R is energized and the rectifier D ¹ is switched on via the rails 1, 2 of the section AB through the normally open contact 8 of the relay R. The rails 1, 2 are traversed by an essentially uniform current, for example positive polarity, and the relay C is excited accordingly in order to monitor a signal which gives an indication of the journey. If, however, the track section BF is occupied, the relay R will be de-energized, and the other rectifier D- is switched on via the rails of the section AB through the normally closed contact 9 of the relay R. The relay C is energized under these conditions no by a current of negative polarity, so that in this way the corresponding signal indicates a caution. If the train or vehicle is on section AB, relay C is short-circuited and, under this condition, causes the signal to be displayed as dangerous.

In a modified arrangement, only a single rectifier can be used as in the systems of FIGS. 1, 2, 3, the relay R then being arranged so that there is an inversion in the connection.

Application or switching of the rectifier to the rails ι, 2 causes when the relay R is energized or de-energized.

Claims (7)

Patent claims: 1. Electrical signaling system for railways and the like, in which the in block sections divided tracks serve as conductors and are connected in sections to a power source and a relay, characterized in that at one end of the track circuit (block section) an AC power source and a DC relay and rectifier are arranged at the other end thereof. 2. Signal system according to claim i, characterized in that the rails (i, 2) of a block section with the alternating current source (S), the relay (C) and the rectifier (D) are connected in parallel or in series. 3. Signal system according to claim 2, characterized in that one or the other block section is monitored by the connection of the rectifier (D) to the rails (1, 2) according to the traffic conditions. 4. Signal system according to claim 1, characterized in that an inductance (6) is turned on in the circuit of the DC relay (C). 5. The signal system of claim 2, wherein the block relay is connected to the power source the rails are connected in series, characterized in that a resistor (7) is connected in parallel with the relay (C "). 6. Signal system according to claim 3, characterized in that the connections of the rectifier (D) to the rails (i, 2) are reversed by a control relay (R) which is switched over the rails of an adjacent track section (BF), wherein the block relay (C) is polarized so that it responds to different current directions in the rails (1, 2j. 7. Signal system according to claims 3 to 6, characterized in that two oppositely arranged rectifiers (D ¹ , D ² ) are provided, one or the other of which is switched on via the rails (1, 2) , depending on whether the control relay (R) is energized or de-energized. 1 sheet of drawings