US 4,309,628 A · Pulse generation by changing magnetic field

Abstract

A pulser unit is composed of two high strength magnets spaced apart from one another and establishing an intense magnetic field therebetween. Forward faces of the two magnets establish a working surface for the pulser unit. A Wiegand wire module consisting of a Wiegand wire segment around which a pickup coil is wound is mounted in the pulser unit immediately behind the working surface of the pulser unit and adjacent the sides of the two spaced apart magnets. The magnetic field is sufficiently strong to determine the state of the Wiegand wire. When a low reluctance element is brought adjacent to the front of the working surface, the field is substantially distorted and the field to which the Wiegand wire is subjected changes materially. The result is that the Wiegand wire switches state and the substantial rate of change of the flux in that switching of state is sensed by the pickup coil to provide an output pulse. Similarly, removal of the low reluctance element causes the field to revert so that the wire switches state back thereby inducing an output pulse in the pickup coil. The pulser can conveniently be kept stationary while the actuating low reluctance element is moved past the working face of the pulser.

Claims13

Dependent claims

A pulser for use in the generation of a pulse in response to magnetic field distortion comprising:

first and second magnets spaced apart from one another and oriented relative to one another so that a first pole of said first magnet and a second pole of said second magnet define a working surface of said pulser, the polarity of said magnets having opposite orientation so that said first pole of said first magnet and said second pole of said second magnet have opposite polarities,
said magnets establishing a magnetic field between them,
a Wiegand wire module having a predetermined position in the field between said magnets, said module including a Wiegand wire segment and a pickup coil,
said first and second magnets and said module all being positioned rearward of said working surface of the pulser,
the configuration of said magnetic field between said magnets distorting materially in response to a material change in the reluctance path provided adjacent to and forward of said working surface of the pulser,
said position of said Wiegand wire in said field being such that said wire switches state in response to said material distortion of said field.

3 more elements

Dependencies are inferred from the claim text.

Pulse generation by changing magnetic field

Life of this patent

Pulse generation by changing magnetic field

Life of this patent

Abstract

Claims13