MEMS device with supplemental flux concentrator

A microelectromechanical modulating magnetic sensor comprising:

• a base;
• a magnetic transducer supported by a first support structure, at least a portion of the magnetic transducer being located in a first plane;
• the magnetic transducer providing an output in response to a magnetic field associated with the base;
• a plurality of movable flux concentrators positioned to move relative to the magnetic transducer;
• the plurality of movable flux concentrators having a region of maximum concentration of flux at a predetermined region associated with the positions of the plurality of movable flux concentrators;
• at least one stationary flux collector positioned on the first support substantially within the first plane to collect and transfer flux for transfer onto at least one movable flux concentrator;
• a second support structure operatively associated with the base for enabling the plurality of movable flux concentrators to move laterally in tandem substantially within a second plane parallel to the first plane;
• the at least one flux collector being located in the first plane so as to overlap a first of the plurality of movable flux concentrators to enable continuous flux transfer during the movement of the plurality of movable flux concentrators from the at least one stationary flux collector onto the first of the plurality of movable flux concentrators;
• and, during movement of the plurality of movable flux concentrators, flux is transferred from the first of the plurality of movable flux concentrators to a second of the plurality of movable flux concentrators;
• the first and second movable flux concentrators being positioned a fixed distance apart such that a region of maximum concentration of flux forms therebetween;
• the first and second movable flux concentrators moving in tandem from a first position in which one of the first and second movable flux concentrators shields the magnetic transducer from the flux which flows between the first and second movable flux concentrators to a second position in which the magnetic transducer is adjacent the region of maximum concentration of flux;
• the distance between the first and second planes being in the range of approximately 2 to 8 microns;
• a power source for causing the movable flux concentrators to move at a frequency within the predetermined frequency range;
• whereby as the at least one movable flux concentrator moves from a first position to a second position the region of maximum concentration of flux moves relative to the transducer to thereby modulate the output from the magnetic transducer.

A microelectromechanical modulating magnetic sensor comprising:

• a magnetic transducer, at least part of which is positioned in a first plane and supported by a first support, the magnetic transducer providing an output in response to a magnetic field;
• first and second movable flux concentrators positioned to move relative to the magnetic transducer in tandem substantially in a second plane substantially parallel to the first plane;
• the first and second movable flux concentrators being spaced apart from one another with a intermediate area therebetween such that magnetic flux flows into the intermediate area from the first to the second movable flux concentrator during operation of the sensor;
• at least one flux collector, at least part of which is positioned in the first plane and fixedly mounted to the first support, the at least one flux collector operative to collect flux for transfer onto the first movable flux concentrator;
• the at least one flux collector being such that the at least one flux collector overlaps at least a portion of the first movable flux concentrator so as to allow flux transfer without inhibiting movement of the first movable flux concentrator;
• the first and second movable flux concentrators being positioned so as to move from a first position in which one of the first and second movable flux concentrators shields the magnetic transducer from the flux which flows between the first and second movable flux concentrators to a second position in which the magnetic transducer is adjacent the intermediate area so as to allow exposure of the magnetic transducer to the flux;
• a power source for causing the movable flux concentrators to move at a frequency within a predetermined frequency range;
• whereby as the first and second movable flux concentrators move from a first position to a second position the intermediate area moves relative to the transducer from a first position in which the magnetic transducer is not exposed to flux flowing between the first and second movable flux concentrators to a second position in which the magnetic transducer is exposed to flux flowing between the first and second movable flux concentrators to thereby modulate the output from the magnetic transducer.