Electricity: measuring and testing – Magnetic – Fluid material examination
Patent
1993-11-01
1995-08-22
Snow, Walter E.
Electricity: measuring and testing
Magnetic
Fluid material examination
324225, 340631, G01N 2774, G01R 3312, G08B 1710
Patent
active
054443679
ABSTRACT:
A device to detect the presence of particles, principally metallic particles, in fluid lines. The fluid to be sampled flows through a former on which is wound a coil assembly comprising a sensor coil flanked upstream and downstream by two field coils. The former is constructed with a double wall and air gap such that pressure fluctuations in the fluid are not transmitted to the coil assembly to adversely affect the positions and readings of the coils. The field coils are driven by a high frequency signal derived from a crystal oscillator and the upstream and downstream sections are wound in opposite directions such that the magnetic field from each section is cancelled out in the plane of the sense coil. When a ferromagnetic or conductive particle passes through the winding structure, the coupling in the sense coil is disturbed as the particle first interacts with the field in the upstream section of the field coil and later with the field in the downstream section of the field coil as it passes through the Sensor Coil Assembly (SCA). A characteristic signature is generated in the sense coil which results from the vector summation of these transient imbalance signals with the steady-state signal from the opposed field coils. Analysis of the phase of this signature can be used to detect and distinguish between the presence of ferromagnetic and non-ferromagnetic conductive particles. Since ferromagnetic and non-ferromagnetic conductive particles interact with the field via permeability and eddy current effects respectively, the transient phase signature has a characteristic lag-lead or lead-lag sequence depending on the nature of the particle.
REFERENCES:
patent: 2215605 (1940-09-01), De Lanty
patent: 3231815 (1966-01-01), Spencer
patent: 3433057 (1969-03-01), Halsey
patent: 3665298 (1972-05-01), Geiger
patent: 3676773 (1972-07-01), Eckhardt
patent: 3748576 (1973-07-01), Sigournay
patent: 4100491 (1978-07-01), Newman, Jr. et al.
patent: 4144741 (1979-03-01), Nakamoto et al.
patent: 4176545 (1979-12-01), Oddo
patent: 4219805 (1980-07-01), Magee et al.
patent: 4300097 (1981-11-01), Turner
patent: 4563644 (1986-01-01), Lenander et al.
patent: 4651091 (1987-03-01), Chambers et al.
patent: 4651092 (1987-03-01), Brunsch et al.
patent: 4692698 (1987-09-01), Lewis
patent: 4731578 (1988-03-01), Tsapraxis
patent: 4766373 (1988-08-01), Chambers et al.
patent: 4785239 (1988-11-01), Brunsch et al.
patent: 4926120 (1990-05-01), Veronesi et al.
patent: 5001424 (1991-03-01), Kellett et al.
patent: 5041856 (1991-08-01), Veronesi et al.
George Douglas B.
Kempster Robert W.
Minister of National Defence
Snow Walter E.
LandOfFree
Method and apparatus for detecting particles in a fluid having c does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for detecting particles in a fluid having c, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for detecting particles in a fluid having c will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2144322