Abstract: A voltage limiting device (15) for constant current circuits (10) comprises input terminals (153) for connecting the voltage limiting device to a current supply (11) of a constant current circuit, output terminals (154) for connecting the voltage limiting device to a load, a voltage clamping circuit (151), and a switching circuit (152). The input terminals (153) are connected to the output terminals (154) under a normal operating condition. The voltage clamping circuit (151) is configured to clamp a voltage across the output terminals to a first voltage threshold and the switching circuit is configured to short-circuit the output terminals when a second voltage threshold across the output terminals is exceeded longer than a predetermined time period.

Abstract: A safety device for gloved intervention. A glovebox comprises a wall comprising an opening. A light curtain is in the glovebox. Upon acquisition of an object intervening through the curtain, a machine's operation is stopped. The device comprises a shaft extending inside the glovebox along an axis of rotation, an actuation element actuatable to allow axial movement of the shaft, a housing through which the shaft is guided, and a cover fastened to the shaft to a rotational axis. The housing is fastened to a wall. In a closed state, the cover closes the opening and can switch into an open state with rotational movement. The shaft and the housing are coupled to secure against twisting in a prevention position. The shaft is rotatable, in a rotational position, for switching between closed and open cover states. The curtain can detect the shaft and/or the cover in the rotational position.

Abstract: The invention relates to a polymer sliding material, capable of running dry and comprising a polymer matrix material and fillers, wherein the fillers comprise reinforcing particles, hard material particles and lubricant particles. The invention furthermore relates to a mechanical seal, comprising a rotating sealing ring and a stationary counter ring, wherein the sealing ring and/or the counter ring encompass the polymer sliding material, which is capable of running dry. Furthermore, the invention relates to the use of such polymer materials, which are capable of running dry, for dry-running applications, especially as a material for displacement elements in wet-running and dry-running pumps.