| 摘要 |
PROBLEM TO BE SOLVED: To provide an electric current sensor that can stably measure a value of an electric current of a measurement object even when a magnetic sensor is arranged at a location distant from an area near a primary conductor.SOLUTION: The electric current sensor is provided which comprises: a primary conductor through which an electric current of a measurement object flows; and a magnetic sensor device 10 that is located at an interval relative to the primary conductor. The magnetic sensor device 10 includes: a first magnetic sensor 12 and second magnetic sensor 13; and a magnetic substance 14, which has in a portion facing the primary conductor, a tapered shape having a width narrowed as coming closer to the primary conductor. An outer shape on a side of the first magnetic sensor 12, and an outer shape on a side of the second magnetic sensor 13 are almost plane-symmetric. The first magnetic sensor 12 and the second magnetic sensor 13 are arranged so that the shortest distances to a symmetry plane of the outer shape of the magnetic substance 14 are equal to each other. Each of the first magnetic sensor 12 and the second magnetic sensor 13 has detection axes 12a and 13a parallel with a direction where the primary conductor and the magnetic substance 14 are connected with the shortest line.SELECTED DRAWING: Figure 5 |
