Patent ID: 7412779

Claim:
A measuring tool comprising: a stationary member; a movable member arranged movable with respect to the stationary member; a detector that detects a displacement of the movable member with respect to the stationary member; a computing section that computes a measurement value from the displacement detected by the detector; a display that displays the measurement value computed by the computing section; and an operating section that gives an instruction to the computing section; wherein the computing section, which comprises a storage that stores the displacement detected by the detector, carries out: a preset operation in which in response to the instruction given by the operating section the displacement detected by the detector is stored in the storage as a measurement reference value and a measurement value computing operation in which a measurement reference value is computed based on a difference between the present displacement and the measurement reference value stored in the storage, and in the preset operation, a judgment operation in which the movable member is judged to be stationary with respect to the stationary member when a variation of the displacement detected by the detector at an interval of a predetermined time has continuously been within a permissible range for a predetermined time is carried out, and when the movable member is judged to be stationary with respect to the stationary member in the judgment operation, the displacement is stored in the storage as the measurement reference value.