Patent ID: 7886600

Claim:
A motion sensor comprising: three magnetic sensing parts for detecting magnetic field strength in 3-axis directions orthogonal to one another; and three acceleration sensing parts for detecting accelerations in the 3-axis directions; wherein each of the acceleration sensing parts has a magnet body constituted to be able to displace depending on acceleration, and a magnet displacement detection head for detecting a displacement of the magnet body, the three magnetic sensing parts and the three magnet displacement detection heads being all made of the same type of magnetic detection elements which operate based on common operation principles, the three magnetic sensing parts and the three acceleration sensing parts being integrated into one modular package together with one electronic circuit for controlling a total of six magnetic detection elements, and the magnet displacement detection head includes a main detection section for detecting magnetism generated by the magnet body, and a compensating detection section for detecting an ambient magnetic field acting on the magnet displacement detection head, the main detection section and the compensating detection section being arranged to be able to detect magnetism in the same axial direction such that an output signal of the magnet displacement detection head is compensated by subtracting an output of the compensating detection section from an output of the main detection section.