초록 ▼

An improved magnetic sensor for use in measuring the position, velocity and/or direction of movement of an object having alternating zones in the direction of movement of different magnetic conductivity comprises a permanent magnet member having a pole face facing the moving object and having an axi

An improved magnetic sensor for use in measuring the position, velocity and/or direction of movement of an object having alternating zones in the direction of movement of different magnetic conductivity comprises a permanent magnet member having a pole face facing the moving object and having an axis transverse to the direction of movement thereof. A ferromagnetic strip of high permeability is mounted on the face of the magnet coaxial therewith and has a length dimension in the direction of movement of the object which is greater than the width dimension transverse to the direction of movement. A pair of sensor elements are mounted on the ferromagnetic strip, one on each of the opposite sides of the magnet axis in the direction of movement of the object. The ferromagnetic strip distorts the field of the permanent magnetic member in the area of each of the sensor elements such that the flux lines in the area of each of the sensors are urged toward a transverse direction relative to the direction of movement of the object, whereby the flux field in the area of each of the sensors is uniform. The ram in a metal die casting machine can be positioned using the sensor and/or the position, velocity and direction of movement of the ram can be determined through use of the sensor.

대표청구항 ▼

A transducer for producing electrical pulse signals in response to movement relative thereto of an object having alternating zones of different magnetic conductivity, comprising circular permanent magnet means having an axis and an end for facing said object, said end including field distorting mean

A transducer for producing electrical pulse signals in response to movement relative thereto of an object having alternating zones of different magnetic conductivity, comprising circular permanent magnet means having an axis and an end for facing said object, said end including field distorting means for distorting the magnetic field of said permanent magnet means on opposite sides of said axis with respect to the direction of relative movement between said object and transducer, the first and second magnetic field sensor element means on said field distorting means, said first sensor element means being offset from said axis on one of said opposite sides thereof, and said second sensor element means being offset from said axis on the other of said opposite sides thereof, said field distorting means having a length in said direction of movement generally corresponding to the diameter of said magnet means and a width transverse to said direction of movement of about one-half said diameter, and each said first and second sensor element means having a dimension transverse to said direction of movement generally corresponding to said width of said field distorting means.