Abstract: A contact element for transmitting current to a workpiece for use in electrochemical material working. The contact element (10) encompasses a contact carrier (11) and a contact piece (13) which is secured to the contact carrier (11) and comes in contact with the workpiece during operation. The contact carrier (11) comprises zirconium or a zirconium alloy. The contact piece (13) is a solid disk of platinum or a platinum alloy, and is welded to the end face (14) of the contact carrier (11).

Abstract: A mixing block (40) for mixing a combustible gas mixture, consisting of at least two components, for processing materials by means of temperature and pressure concussions, particularly for thermal deburring apparatuses, is suggested, having a gas feed borehole (43 and 44) for each gas component, opening into a mixing and ignition duct (61, 68, 69, 73, 74, 75), wherein a main valve (48, 49, 50, 51 and 52, 53) for admitting the gas components into the mixing and ignition duct (61, 68, 69, 73, 74, 75) and for closing the gas feed boreholes (43 and 44) so as to be gas-tight during the combustion process is arranged in each gas feed borehole (43 and 44).

Abstract: In an apparatus for treating workpieces by means of the igniting of a gaseous mixture in a work chamber for receiving the workpiece, it is proposed that the work chamber and optionally the supply duct for the gaseous mixture, as well as a mixing block for preparing the gaseous mixture which precedes the supply duct, are provided at least in part with a lining of ceramic material in the form of aluminum oxide or zirconium dioxide, in order to intercept the corrosive action exerted by the ignition of the combustion gas-oxygen mixture upon these parts of the apparatus.

Abstract: A mixing block, for attachment to a combustion chamber in which a solid body or material is briefly subjected to high temperature and pressure by the detonation of an explosive gas mixture, is composed of three block-like parts clamped together by screws. This enables the relatively long channels subject to explosion stresses to be constituted of lengthwise bores in the middle block connected by milled short cross-connections. The protective cutoff valve is an automobile type valve set in the upper block piece, which can also have an insert of temperature resistant material adjacent to the mixing chamber portion of the middle block. The ignition device is not shown in the drawing, but is usually provided in the mixing block structure. In the section of the mixing block illustrated in the drawing only one of the gas connections to the mixing chamber (19) is shown.