Magnetic field sensing apparatus for sensing the proximity of a

Electricity: measuring and testing – Measuring – testing – or sensing electricity – per se – Frequency of cyclic current or voltage

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

324 46, 338 32R, 324 34D, G01R 3312

Patent

active

040217280

ABSTRACT:
Apparatus is provided for producing an output signal upon sensing the proximity of a member having relatively high magnetic permeability. The apparatus includes a magnetoresistive element which is comprised of an insulating substrate upon which first and second ferromagnetic strips are provided. The ferromagnetic strips define first and second main current conducting paths which are respectively perpendicular to each other. The strips are connected in series to define a junction therebetween from which an output signal is derived. Current supply terminals are provided for furnishing an energizing current to the magnetoresistive element, which energizing current flows in a direction from one to the other of the current supply terminals. A bias magnetic field is provided in a direction perpendicular to one of the main current conducting paths and which is sensed by the element. A portion of this bias field is received by a member having a relatively high magnetic permeability which is proximate the element, thereby altering the distribution of the received portion of the bias field to produce a composite field which can be considered a vector formed of the bias field and the field attributed to the permeable material. The composite field is a function of the spacing between the element and the member and the longitudinal positioning of the member with respect to the element. This composite magnetic field is sensed by the element, whereby an output signal is produced from the junction in the element as a function of the relative positions of leading and trailing edges of the member with respect to the magnetoresistive element.

REFERENCES:
patent: 2997648 (1961-08-01), Bozorth
patent: 3405355 (1968-10-01), Hebbert
patent: 3493694 (1970-02-01), Hunt
patent: 3546579 (1970-12-01), Paul et al.
patent: 3613000 (1971-10-01), Weir et al.
patent: 3777273 (1973-12-01), Baba et al.
patent: 3928836 (1975-12-01), Makino et al.
Hill, Y. M.; Velocity Sensing with a Hall Probe, IBM Tech. Bul. vol. 6, No. 6, Nov., 1963, p. 54.
Bate et al., Magnetoresistive Read Heads, IBM Tech. Bul., vol. 17, No. 4, Sept., 1974, pp. 967-968.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Magnetic field sensing apparatus for sensing the proximity of a does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Magnetic field sensing apparatus for sensing the proximity of a , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Magnetic field sensing apparatus for sensing the proximity of a will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-347933

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.