DE918941C - Gespraechszaehler for telephone systems with additional armature return spring - Google Patents

Description

Call counter for telephone systems with an additional anchor return spring It is well known that the call counters provided in telephone exchanges with self-connection must work under very different electrical conditions. In particular, this is the case Call counter made the requirement to respond with certainty to both impulses, whose amperage is relatively small, as well as to pulses whose amperage is significantly larger and which are separated by pauses in which the counter of a residual current is flowing through, the current strength of which has a certain finite value owns.

These two conditions contradict each other, and the common ones Counters are able to control a work area, its uppermost limit (Residual current) and its lowest limit (impulse current) are not always sufficiently apart, in order to meet the conditions that arise in practical operation.

To push those boundaries and create a conversation counter, which is sufficiently sensitive to respond to small impulse currents, and at the same time has a sufficiently high degree of insensitivity to the residual currents, has already been proposed, in addition to the usual armature return spring of the call counter magnet to provide at least one more return spring, which only comes into effect after the anchor has covered a large part of its approach path.

This is to enable the meter to work with weak excitation currents to work because when the tightening force starts, only one spring is used effective is. On the other hand, the meter can handle relatively high residual currents work because the drop of the anchor through the combined action of at least two Springs.

The invention is particularly effective and expedient Design and arrangement for a second additional spring.

According to the invention, the additional spring is designed as a double spring so that it is attached to the bobbin of the counter magnet, preferably on its front flange can be placed without any fastening means for holding them required are.

Among other things, this has the considerable advantage that with meters that are already in operation can be equipped with such a spring, without any structural changes or fastening work for this purpose respectively-. Recalibrations would have to be carried out.

An embodiment is shown in the drawing, which is in the Fig. R, 2 and 3 a call counter magnet according to the invention schematically in side view or shows in plan and front view.

With E the electromagnet of the counter is designated, with N its magnetic core, with F the front flange of the bobbin, with M1 the usual armature return spring, with M2 the additional armature return spring and with A the armature of the counter magnet.

When an impulse arrives, the armature A is removed from the electromagnet E attracted and only needs to overcome the counterforce of the usual armature spring M1. As soon as the anchor A has covered a large part of its way, it comes into contact with the second spring M2, and from that moment on the electromagnet must do the Overcome the opposing force of both springs. The attraction of the electromagnet is however now the distance between the anchor and the core is greatly reduced grown, so that a safe tightening is still guaranteed.

At the end of the armature travel is the retraction force acting on the armature given by the sum of the forces exerted by both springs M1 and M2.

As can be seen from the drawing, the additional spring M2 is a double spring Executed with two tongues m2, which are symmetrical on both sides of the magnetic core N, which means that one-sided forces acting on the counter anchor A are certain In order to fix the spring M2 on the front flange F of the spool the two lateral edges of the tongue are bent twice at right angles (Fig. 2). The spring M2 is pushed onto the flange F from above and remains through the spring effect of the edges bent at right angles in the set position.

The spring M2 is prevented from slipping downwards this rests on a semicircular cutout (Fig. 3) on the magnetic core N. The depth of this incision is chosen so that the spring M2 is necessary for its function correct position reached as soon as it comes to rest on the magnetic core; the setting the spring is therefore carried out automatically without any adjustment work.

Claims (3)

PATENT CLAIMS: r. Call counter for telephone systems, where on the armature in addition to the usual armature return spring at least one further return spring acts, the force of which only begins after the anchor has made a large part of its Has traveled tightening path, characterized in that the further return spring is designed as a double spring so that it is attached to the coil body of the counter magnet, is preferably placed on its front flange without being used for its holder special fasteners are required. 2. Call counter according to claim r, characterized in that the additional spring (M2) is essentially U-shaped curved leaf spring is formed, one leg of which is for attachment to the bobbin serves, while the other leg of two opposite the anchor, symmetrically is formed on both sides of the magnetic core arranged tongues. 3. Call counter according to claims z and 2, characterized in that the one for fastening to the coil body serving leaf spring legs has side edges bent twice at right angles, where the spring is pushed from above over the front spool flange (F) and on this is held. 4 .. Call counter according to claim r to 3, characterized through a central, approximately semicircular cutout on the fastening leg the spring (M2) between the two spring tongues opposite the armature (A) (nz2), at which cutout the spring when placed on the counter against the protruding one End of the magnetic core (N) comes to rest and automatically the correct one Assumes working position and at the same time is prevented from slipping.