Abstract: A three-dimensional object is produced by sequentially laminating a plurality of layers. The method includes setting a plurality of coordinate points at a predetermined interval on a profile of a model section corresponding to a layer to be formed, obtaining information regarding distances between a plurality of the coordinate points, and scanning a photo-curing resin solution with light from a light source, in correspondence with a direction of a straight line passing through mated coordinate points giving a distance shorter than a maximum value among the distances between a plurality of the coordinate points.

Abstract: In an impact type clamping apparatus including a motor unit for generating a pulsatory driving torque, a main spindle driven by said pulsatory driving torque to rotate a fastening member, a detecting unit for detecting a pulsatory torque applied to the main spindle, a calculating circuit for calculating a clamping force in accordance with a peak value of the pulsatory torque, and a control unit for stopping the operation of said motor unit when the calculated clamping force exceeds a desired clamping force, said clamping force is calculated not only from the peak value of the pulsatory torque but also from an increasing coefficient which represents a relationship between the peak value of the pulsatory torque and an increment of the clamping force.

Abstract: An impact wrench with a torque controlling faculty including an air motor for generating a primary torque, an oil pressure pulse generating unit for converting the primary torque into a pulsatory secondary torque, a main spindle to which the pulsatory secondary torque is applied, a transducer for detecting the pulsatory secondary torque and a shut-off valve which is closed to stop a supply of a compressed air to the air motor when the secondary torque exceeds a predetermined threshold value. The main spindle is made of material having the magnetic strictive effect and the distortion of the main spindle is detected by a pair of coils arranged in opposition to the main spindle. The coils are connected into a bridge circuit together with resistors and an exciting current having a sinusoidal waveform is supplied to a first set of diagonal points of the bridge circuit.