Metal converter vessel with a cooling pipe system that extends through the vessel from the bottom to the lid
DE740418C
Pantographs for rail vehicles
DE744008C
Spark gap for surge arrester
DE740345C
Device for performing arc welds using a coated electrode
DE740533C
Relayless electrical control device with a choke coil, the direct current bias of which is controlled
DE740449C
Device for the excitation of selective protective relays assigned to several phases and for their switchover to the electrical quantities characteristic of the various fault cases in multi-phase systems
SU24811A1
Device for changing the cross section of fixed cores of the magnetic system of electrical machines
