초록 ▼

A read head for a Wiegand type wire establishes an asymmetric field to which the wire is subjected. A setting magnet at a first position establishes a sufficiently strong positive field to set the core and shell of the Wiegand wire in a first confluent state. At a second position, the field is suffi

A read head for a Wiegand type wire establishes an asymmetric field to which the wire is subjected. A setting magnet at a first position establishes a sufficiently strong positive field to set the core and shell of the Wiegand wire in a first confluent state. At a second position, the field is sufficiently negative so as to assure that the core switches state thereby establishing a reverse state for the wire. The field does not go strongly negative and thus the state of the shell is not reversed. At a third position, the field becomes sufficiently positive so as to cause the core to reverse its state again thereby switching the wire from its reverse state to its confluent state. This particular switching occurs in close proximity to the pickup coil thereby providing an output pulse in response to the switch of state of the wire from reverse state to confluent state.

대표청구항 ▼

A pulse generator comprising: a Wiegand wire having core and shell portions and having the characteristic that it requires the aid of an external field to switch from its confluent state to its reverse state, read head means to establish a predetermined magnetic field along a predetermined path, the

A pulse generator comprising: a Wiegand wire having core and shell portions and having the characteristic that it requires the aid of an external field to switch from its confluent state to its reverse state, read head means to establish a predetermined magnetic field along a predetermined path, the magnitude and direction of said magnetic field varying along said path, motive means to create relative movement of said head and said wire so that said wire travels along said path from a first position on said path to a final position along said path, said magnetic field having at least a first magnitude in a first direction at said first position, said first magnitude being sufficiently great to set the magnetization of both said core and said shell in a predetermined first confluent state, said field having a second magnitude in a second direction at a second position downstream from said first position along said path, the absolute value of said second magnitude being substantially less than the absolute value of said first magnitude, said second magnitude being sufficient to switch the magnetization of said core thereby switching the state of said wire from said first confluent state to said reverse state, said second magnitude being insufficient to set the magnetizatin of said shell, said field having a third magnitude in said first direction at a third position downstream from said second position, said third magnitude being sufficient to switch the magnetization of said core thereby switching said wire from said reverse state to said first confluent state at said third position, and a pickup coil positioned adjacent to said third position to provide an output pulse in response to the switch of state of said wire from said reverse state to said first confluent state.