Abstract: A device for detecting electrically conductive particles in a liquid flowing in a pipe section, with a transmitter coil surrounding the pipe section for inducing eddy currents in the particles, at least one first inductive receiver coil surrounding the pipe section and a second inductive receiver coil which is spaced axially to the first receiver coil and which surrounds the pipe section, the first and the second receiver coils being located in the region of the transmitter coil and being subtractively connected, in order to output a difference signal according to the eddy currents induced by the transmitter coil, and the transmitter coil forming the primary side and the receiver coils forming the secondary side of a transformer arrangement. An evaluation unit evaluates the difference signal in order to detect passage of electrically conductive particles in the pipe section.

Abstract: A method and apparatus are provided for monitoring the quality of lubricant that is in a gear mechanism or machine that contains effective materials. A sample of the lubricant or of the vapor that escapes from the lubricant is withdrawn from the gear mechanism or machine. The sample is conveyed to an ion mobility spectrometer, where materials present in the vapor phase above the lubricant are analyzed. The change of the content and of the type of the analyzed materials in the sample is utilized as the actual condition for the aging of the lubricant.

Abstract: A method and apparatus are provided for monitoring the quality of lubricant that is in a gear mechanism or machine that contains effective materials. A sample of the lubricant or of the vapor that escapes from the lubricant is withdrawn from the gear mechanism or machine. The sample is conveyed to an ion mobility spectrometer, where materials present in the vapor phase above the lubricant are analyzed. The change of the content and of the type of the analyzed materials in the sample is utilized as the actual condition for the aging of the lubricant.