Hall effect motion detector responsive to dual frequency stimuli

A motion and shock detector system comprising a sensor and circuit means for generating an electrical signal responsive to low frequency motion stimuli or higher frequency stimuli to said sensor, said sensor comprising:

• a first bridge;
• a magnetic field producing device on said first bridge;
• a second bridge;
• a magnetic field sensitive device on said second bridge;
• said first bridge and sid magnetic field producing device having a predetermined resonant frequency;
• said second bridge and said magnetic field sensitive device having a predetermined resonant frequency different from the predetermined resonant frequency of said first bridge and said magnetic field producing device;
• whereby said sensor responds to stimuli at two different resonant frequencies;
• said magnetic field sensitive device producing an electrical signal responsive to said magnetic field;
• said circuit means including means for blocking D.C. signals from said magnetic field sensitive device and for amplifying A.C. signals from said magnetic field sensitive device to produce output signals responsive to changes in the magnetic field at said magnetic field sensitive device.

A motion and shock detector comprising:

• a base;
• a pair of spaced upstanding columns on said base;
• a first bridge extending betwen said spaced upstanding columns;
• a second bridge extending between said spaced upstanding columns;
• said first bridge supporting a magnetic field producing device;
• said second bridge supporting a magnetic field sensitive device capable of producing an electrical signal responsive to said magnetic filed;
• said first bridge and magnetic field producing device having a predetermined resonant frequency;
• said second bridge and magnetic field sensitive device having a resonant frequency different from the resonant frequency of said first bridge and magnetic field producing device;
• whereby said sensor respond to stimuli in two different frequency ranges.