Abstract: A diamond film formation method includes forming, in a composite of a metal material and a semiconductor material, diamond nuclei on a surface of the metal material at a temperature below 650° C. in a first mixed gas containing at least carbon and hydrogen, and growing the diamond nuclei formed in the composite at a temperature below 750° C. in a second mixed gas containing at least carbon and hydrogen to form a diamond film.

Abstract: A diamond film formation method includes forming, in a composite of a metal material and a semiconductor material, diamond nuclei on a surface of the metal material at a temperature below 650° C. in a first mixed gas containing at least carbon and hydrogen, and growing the diamond nuclei formed in the composite at a temperature below 750° C. in a second mixed gas containing at least carbon and hydrogen to form a diamond film.

Abstract: A first member has a base plate 11 and an abrasive sheet installation portion 12 where an abrasive sheet is fixed. The base plate or the abrasive sheet installation portion is provided with an air-introducing portion 15 as a space penetrating from the back face side to the front face side of the base plate or the abrasive sheet installation portion, and an airflow passes from the back face side to the front face side as a rotary abrasive material rotates. When the first member is used as a single unit, overheating is prevented and swarf can be removed when the rotation of a projection portion as the abrasive sheet installation portion 12 generates an airflow flowing through the air-introducing portion 15.

Abstract: The present invention relates to a rotary grinding jig for use with the rotating shaft of a grinder and the like. The rotary grinding jig includes a base and a grinding member. The base is composed of a central member adapted to be fixed to the rotating shaft of the grinder and a retaining member for the grinding member to be adhesively attached to the grinding member . The central member and the retaining member for the grinding member are removably engaged with each other by means of ridges. The central member can be firmly secured to the rotary shaft by a fixing screw, and the retaining member for the grinding member can be removed with the central member remaining attached to the rotary shaft. If the grinding member wears out, only the retaining member for the grinding member and the grinding member may be thrown away and exchanged for new ones.

Abstract: Disclosed is a dc-to-dc converter comprising a switching transistor, a pulse-width modulation controller, a sandwich-type planar inductor, which accumulates an electromagnetic energy at ON state and releases the accumulated electromagnetic energy at OFF state of the switching transistor, a smoothing capacitor, a rectifying element, and a planar search coil for detecting an overcurrent flowing the planar coil, disposed on one of the outer surfaces of the soft magnetic layers constituting the planar inductor.

Abstract: Disclosed is a dc-to-dc converter comprising a switching transistor, a pulse-width modulation controller, a sandwich-type planar inductor, which accumulates an electromagnetic energy at ON state and releases the accumulated electromagnetic energy at OFF state of the switching transistor, a smoothing capacitor, a rectifying element, and a planar search coil for detecting an overcurrent flowing the planar coil, disposed on one of the outer surfaces of the soft magnetic layers constituting the planar inductor.