Abstract: The electrical resistance (10) includes a sealed housing (12) with a generally cylindrical shape defined along a longitudinal axis (X), a resistive element (16), extending along a spiral defined around the longitudinal axis (X), and a fluid guiding element (18), defining, with the sealed housing (12), a conduit for guiding a flow of fluid in contact with the resistive element (16). The guiding element (18) has a spiral shape defined around the longitudinal axis (X).

Abstract: A positioning cylinder assembly for subterranean mining applications has a rotary potentiometer connected through a friction wheel transmission with the spindle of the cylinder which is rotated when the piston is axially displaced therein. The friction wheel assembly comprises a pinion wheel connected to the spindle and a hollow wheel connected to the rotary potentiometer, that not only matches the pitch of the spindle to the rotary spring of the potentiometer but also functions as a slip clutch for zero setting of the potentionmeter and the piston.

Abstract: An electrode for level detection includes a detection electrode including conductor portions and resistor portions arranged and formed one after the other in a level change direction. An insulating coating layer is formed on either each conductor portion or each resistor portion. The insulating coating layer may be of a film having a property to repel a liquid to be measured.