Euro-Matsushita Electric Works Aktiengesellschaft

Matsushita Electric Works (Europe) Aktiengesellschaft

Friedrich Plappert

Johannes Oberndorfer

Herbert Elsinger

Shigeru Tajima

A magnetic system for an electromagnetic relay comprises at least two iron pieces extending in parallel through the entire length of one common coil , each iron piece being part of its own magnetic circuit for operating an armature which is disposed in this magnetic circuit to operate ah associated contact system. The spacing between the iron pieces inside the coil is substantially smaller than the largest cross-sectional dimension of each iron piece in order to make maximum use of the magnetic flux produced by the coil with minimum loss and minimum stray flux.

Magnetic system for an electromagnetic relay

In an electrical circuit arrangement, specifically a sequential blasting system as used in mining, the individual circuit units 12 are contacted by a continuous flat cable 10 in such a way that each wire 16 to 19 of the cable 10 has a bared section 21 which is soldered to a contact pad 22 to 26 of a conductor pattern 15 disposed on a printed circuit board 11 which carries the circuit elements of the circuit unit 12. This not only minimizes the total number of contacts but also prevents the contact points from increasing the line resistance and prevents any faulty contact point from interrupting the line.

Circuit arrangement having a plurality of circuit units and a common

A casing 14 for a junction included in a flat cable 10, e.g. for a trigger stage of a sequential blasting system, consists of two casing portions 12, 13 adapted to be fixed to each other by screwing within the lead-through regions of the cable. The casing portions 12, 13 constitute cramping areas for fixing the cable 10 to the casing 14 in a direct, non-positive way, wherein the screws 23 which interconnect the two casing portions 12, 13 at the same time create the cramping pressure. An additional positive engagement between the cable 10 and the casing 14 is achieved by engagement between a tube 25 which receives the screw 23 and a hole 29 provided in a center web 28 of the cable. Tensile strain occurring within the cable 10 is thus diverted via the casing 14 around the electrical equipment provided in the casing and soldered to the wires 19 of the cable 10. Even under high tensile forces, the soldering points are thus not exposed to any strain.

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Holzkirchen, Germany

Friedrich Plappert