Abstract: An impact rotation tool including a drive source, an impact force generation unit that generates an impact force for converting power from the drive source to pulsed torque, a shaft that transmits the pulsed torque to a bit used to perform a tightening task, a torque measurement unit that measures torque applied to the shaft as measured torque, a rotation angle measurement unit that measures a rotation angle of the shaft, a tightening torque calculation unit that calculates an angular acceleration from the rotation angle to calculate a tightening torque based on the angular acceleration and the measured torque, and a controller that controls the drive source based on the tightening torque.

Abstract: An impact rotation tool includes an impact force generator that changes power of a drive source into pulsed torque to generate impact force. An output shaft transmits the pulsed torque to a bit based on the impact force. A torque measurement unit measures a shaft torque applied to the output shaft. An angular acceleration measurement unit measures angular acceleration of the output shaft. A moment of inertia calculator calculates moment of inertia of the bit coupled to the output shaft when rotated by the output shaft based on the shaft torque and the angular acceleration. A torque calculator calculates tightening torque based on the angular acceleration, the shaft torque, and the moment of inertia. A controller controls the drive source based on the tightening torque.

Abstract: An impact rotation tool including a drive source, an impact force generation unit that generates an impact force for converting power from the drive source to pulsed torque, a shaft that transmits the pulsed torque to a bit used to perform a tightening task, a torque measurement unit that measures torque applied to the shaft as measured torque, a rotation angle measurement unit that measures a rotation angle of the shaft, a tightening torque calculation unit that calculates an angular acceleration from the rotation angle to calculate a tightening torque based on the angular acceleration and the measured torque, and a controller that controls the drive source based on the tightening torque.

Abstract: An inner cutter for a dry shaver is fabricated from a metal plate to have a plurality of blades each provided with cutting edges. The metal plate includes a plurality of parallel straight slits to leave an array of straight beams each defined between the adjacent ones of the slits. The beams are forged and ground at a segment of each beam to give the cutting edges thereto. After making the cutting edges, the metal plate is bent into a generally U-shaped configuration so as to correspondingly curve the beams and shape the beams into the blades having the arcuate contour and the cutting edges. The metal plate is provided with a joint for connection with a driving source of moving the inner cutter relative to an outer cutter.

Abstract: In an oscillation type linear actuator for reciprocally moving a plurality of moving members held in parallel with each other in a predetermined direction owing to electromagnetic action between a stator and them, two moving members reciprocally moving in opposite phases with each other are coupled by a coupling member having spring function, and a non-displacing portion of a plate spring portion of the coupling member which is not displaced substantially is restricted by a stopper. Even when an external force is applied to one of two moving members reciprocally moving in the opposite phases each other, motion of the other moving member is transmitted to the moving member via the coupling member, so that reduction of amplitude of the moving member to which the external force is applied can be restricted, and a balance of amplitudes of two moving members is maintained.

Abstract: A shaving head for a dry shaver is capable of increasing the cutting efficiency, yet allowing the use of the inner cutter of simple structure. The shaving head has a slit cutter unit composed of an outer cutter shaped to have a top surface for contact with a user's skin, and an inner cutter in contact with a bottom surface of the outer cutter. The outer cutter has a U-shaped structure with a pair of legs connected by a crossbar, and to have a plurality of slits which are spaced in a lengthwise axis of the outer cutter to leave a plurality of bridges each between the adjacent ones of the slits. The slits extend continuously over a full width of the crossbar and into upper ends of the legs in a direction generally perpendicular to the lengthwise axis, giving two straight slit paths respectively on opposite width ends of the outer cutter. The straight slit paths on the opposite width ends are staggered with respect to each other along the lengthwise axis.

Abstract: An oscillatory linear actuator including a plurality of movable elements configured to move in a linear direction, a stationary component configured to drive the plurality of movable elements to move in the linear direction, and a plurality of connecting devices elastically connecting the plurality of movable elements with each other and positioned on at least one end portion of the plurality of movable elements in the linear direction, each of the plurality of connecting devices being extending away from the plurality of movable elements in opposite directions.

Abstract: In an oscillation type linear actuator for reciprocally moving a plurality of moving members held in parallel with each other in a predetermined direction owing to electromagnetic action between a stator and them, two moving members reciprocally moving in opposite phases with each other are coupled by a coupling member having spring function, and a non-displacing portion of a plate spring portion of the coupling member which is not displaced substantially is restricted by a stopper. Even when an external force is applied to one of two moving members reciprocally moving in the opposite phases each other, motion of the other moving member is transmitted to the moving member via the coupling member, so that reduction of amplitude of the moving member to which the external force is applied can be restricted, and a balance of amplitudes of two moving members is maintained.

Abstract: An oscillatory linear actuator including a plurality of movable elements configured to move in a linear direction, a stationary component configured to drive the plurality of movable elements to move in the linear direction, and a plurality of connecting devices elastically connecting the plurality of movable elements with each other and positioned on at least one end portion of the plurality of movable elements in the linear direction, each of the plurality of connecting devices being extending away from the plurality of movable elements in opposite directions.

Abstract: An inner cutter for a dry shaver is fabricated from a metal plate to have a plurality of blades each provided with cutting edges. The metal plate includes a plurality of parallel straight slits to leave an array of straight beams each defined between the adjacent ones of the slits. The beams are forged and ground at a segment of each beam to give the cutting edges thereto. After making the cutting edges, the metal plate is bent into a generally U-shaped configuration so as to correspondingly curve the beams and shape the beams into the blades having the arcuate contour and the cutting edges. The metal plate is provided with a joint for connection with a driving source of moving the inner cutter relative to an outer cutter.

Abstract: A configuration for forming a gastight space is prevented from being projected from a housing, so that a projection is not formed on the housing. A sealed contact device includes a housing including a container body having an open end portion, the container body being made of ceramic, a metal lid connected to the open end portion to form a gastight space, a stationary contact and a movable contact disposed in the container body, and a sealed vent portion formed in the metal lid, in which the sealed vent portion is formed by sealing a vent hole formed in the metal lid after exhausting a gas in the gastight space and supplying a desired gas into the gastight space, via the vent hole.

Abstract: A configuration for forming a gastight space is prevented from being projected from a housing, so that a projection is not formed on the housing. A sealed contact device includes a housing including a container body having an opening end portion, the container body being made of ceramics, a metal lid connected to the opening end portion to form a gastight space, a stationary contact and a movable contact disposed in the container body, and a sealed vent portion formed in the metal lid, in which the sealed vent portion is formed by sealing a vent hole formed in the metal lid after exhausting a gas in the gastight space and supplying a desired gas into the gastight space, via the vent hole.

Abstract: A cutting tool is provided which includes a steel metal body and a cemented carbide cutting tip secured to the metal body by a metallic layer. The metallic layer has a high-strength metallic portion and a high-toughness metallic portion. The high-strength metallic portion is made of a metal having a thermal expansion rate between a thermal expansion rate of the metal body and the thermal expansion rate of the cutting tip. The high-toughness metallic portion is located between edge portions of a securing region of the metal body and the cutting tip and has toughness larger than that of the high-strength metallic portion.

Abstract: In a method of manufacturing a printed circuit board, a photoresist layer is formed on a three-dimensionally molded substrate through a conductive layer. A planar photomask which is provided with a mask pattern and a light-transmissive pattern is placed in front of the photoresist layer. A parallel light beam is radiated to the photomask in order to give to the photoresist layer an exposed pattern of an intended width "L" in correspondence to the light-transmissive pattern. In the present invention, the light-transmissive pattern is configured so as to satisfy the following relations:when D=0, W/L=1,when D>0, W/L<1,wherein "W" is a width of the light-transmissive pattern for forming the exposed pattern of the intended width "L", and "D" is a distance between the light-transmissive pattern and the photoresist layer. The photoresist layer of the exposed or an non-exposed pattern is removed to leave a patterned area of the conductive layer without the photoresist layer.