Abstract: The disclosure relates to a field housing for enclosing electrical equipment in installations where there is an explosion hazard. To avoid ignition sparks passing between the inside and the outside of the field housing, the field housing can include a housing cup of a cuboidal shape with a rectangle opening with rounded corners which can be closed with a housing cover. A periphery of the opening can be widened into a surrounding sleeve, and the housing cover can include a peripheral collar of a form and size matching the opening in the housing cup such that a flameproof joint is formed between the collar of the housing cover and the sleeve of the housing cup.

Abstract: A pressure medium operated actuator with a position regulator for regulated action on the opening and closing actuation of, for example, a process valve, and with a transmission device for transmitting the movement of a driving member to the position regulator. In order, in a position regulator of this type, to utilize a material pairing which is advantageous per se and, at the same time, to achieve movement transmission which is free of play even in the long term, the position regulator is provided with a resetting lever having a polygonal rotary slide which is prestressed in the manner of a torsion spring and which, by tilting slightly under a torsion spring effect, engages between two parallel round-rod portions of a driver connected to the push-rod.