Abstract: A detector for producing an electrical signal proportional to the concentration of ferromagnetic particulate material in a fluid stream includes a sensing coil arranged to form the inductance coil of a radio frequency oscillator arranged to produce an electrical signal at a base frequency, a magnetic trap for producing a magnetic field and a support for supporting the sensing coil and the magnetic trap in juxtaposition to one another such that, when the coil is disposed within or proximate the fluid stream and electrically connected to the oscillator, energization of the magnetic trap causes ferromagnetic particulate material proximate the coil to be attracted toward the coil resulting in a deviation of the frequency of the signal from the base frequency proportional to the concentration of ferromagnetic particulate material in the fluid stream.

Abstract: The specification describes a method and an apparatus for detecting and quantitatively assessing wear of a machine having ferromagnetic components subjected to wear during operation resulting in the production of ferromagnetic particulate wear debris, and a lubrication system utilizing a lubricating fluid, in which the wear debris becomes entrained, for lubricating the components. The method comprises the steps of passing a sample stream of the lubricating fluid at a predetermined rate of flow axially through the core of an inductance coil of a sample oscillator for producing a time varying signal which deviates from a predetermined value in proportion to the mass of ferromagnetic material contained in the fluid passing through the core, monitoring the rate of change of signal and activating an indicator when the rate of change of the signal exceeds a predetermined level.

Abstract: The specification describes a method and an apparatus for detecting and quantitatively assessing wear of a machine having ferromagnetic components subjected to wear during operation resulting in the production of ferromagnetic particulate wear debris, and a lubrication system utilizing a lubricating fluid, in which the wear debris becomes entrained, for lubricating the components. The method comprises the steps of passing a sample stream of the lubricating fluid at a predetermined rate of flow axially through the core of an inductance coil of a sample oscillator for producing a time varying signal which deviates from a predetermined value in proportion to the mass of ferromagnetic material contained in the fluid passing through the core, monitoring the rate of change of signal and activating an indicator when the rate of change of the signal exceeds a predetermined level.