AN ACTIVE HEADREST HAVIG A MAGNETIC SENSOR

An active headrest having a magnetic sensor is provided to support driver's head and neck continuously by releasing original location of a stopper when external shock which is greater than magnetic force thereof is transmitted from rear part of a vehicle using a magnetic sensor. An active headrest(100) having a magnetic sensor comprises a supporting frame(210), a guide member(220), an operation unit, and an active headrest operation unit. The supporting frame is installed in a seat(S), and of which one part is supporting the active headrest. The other part of the supporting frame is extended downward in the longitudinal direction of the seat. The guide member movably supports the extended end of the supporting frame in back and forth direction of the seat. The operation unit places the end of the supporting frame to rear part of the seat when external shock is transmitted from the rear part of the vehicle and moves the headrest to forward to support the driver's head and neck. The active headrest operation unit has a magnetic sensor unit(M) to release fixed location of the operation unit when external shock is transmitted. The active headrest operation unit is formed at the end of the operation unit to fix the operation unit with magnetic force.