Abstract: A relay driving circuit for a latch-in type magnetic relay having an excitation coil, generating a set current and a reset current of opposite polarity for the coil. A capacitor is provided between the input terminals of the circuit in series with the coil. A set switch is connected in series with the coil and the capacitor, and a reset switch is connected across the series combination. An input voltage level detector is provided to make the set switch conductive, thereby applying the input voltage to the excitation coil and the capacitor to provide the set current. As the input voltage decreases below the trigger level, the detector makes the reset switch conductive to allow the capacitor to discharge current in the opposite direction through the excitation coil.

Abstract: A contact spring arrangement for an electromagnetic relay includes a contact spring forming at least one movable contact for cooperation with a fixed contact, and an actuator which embraces the contact spring and has a first portion for moving the movable contact towards the fixed contact, thereby closing the contact couple, and a second portion for withdrawing the movable contact from the fixed contact, thereby opening the contact couple. The actuator is so shaped that the distance between the location at which the first actuator portion engages the contact spring and the contacting location of the contact couple is greater than the distance between the location at which the second actuator portion engages the contact spring and the said contacting location.

Abstract: Circuit arrangements for the control of a bistable relay having a capacitor connected in series with its excitation winding, in which the series connection of coil and capacitor is connected to excitation voltage for the excitation of the relay and simultaneous charging of the capacitor, and, upon absence of excitation voltage, is short-circuitable through a semiconductor switch having its output circuit parallel-connected with the series connection of coil and capacitor, whereby the relay switches back to its starting position.

Abstract: An electromagnetic switching device comprises a bobbin with a coil mounted thereon, the bobbin forming a protective tube with a contact chamber at each end. Embedded in the bobbin are a plurality of terminals connected to the coil, pole shoes, and contact terminals connected to the pole shoes. An armature is disposed in the tube and has two free end portions coated with contact material facing end portions of the pole shoes that extend from opposite walls of a respective one of the contact chambers. At least one permanent magnet is mounted between flanges of the bobbin at each end of the tube, these magnets and the pole shoes being disposed symmetrically in relation to the longitudinal axis of the tube and at least one further axis perpendicular to such longitudinal axis.