Abstract: A cutting or grinding tool includes a blade. The blade includes a disc-shaped base metal, cutting or grinding tips (edges) provided on a peak (outer circumferential edge) of the base metal, and a protruding coating on a side face of the base metal along the entire outer circumference of the base metal.

Abstract: A cutting or grinding tool includes a blade. The blade includes a disc-shaped base metal, cutting or grinding tips (edges) provided on a peak (outer circumferential edge) of the base metal, and a protruding coating on a side face of the base metal along the entire outer circumference of the base metal.

Abstract: A spare blade 25 is a square plate formed of cemented carbide and to be attached to an outer circumferential surface of a cutter 10 for forming a plane. A flat face 28 forming cutting edges is a convex portion 28a slightly bulging in a shape of a lateral surface of a single cone, and a center of the square plate lies on an axis of the convex portion 28a. An entire surface of the spare blade 25 is covered with a diamond coating film having a thickness of 5 to 25 ?m.

Abstract: An electrical device has a housing that includes a main body and a lid both of which are electrically conductive. The lid is fastened to a top surface of a sidewall of the main body so as to cover the main body. On at least one of a bottom surface of the lid and the top surface of the sidewall of the main body, there are formed a plurality of protrusions at predetermined positions; each of the protrusions abuts against that one of the bottom surface of the lid and the top surface of the sidewall which is opposed to the protrusion. Except at those predetermined positions where the protrusions are formed, there is provided, between the bottom surface of the lid and the top surface of the sidewall of the main body, a gap via which the internal and external spaces of the housing communicate with each other.

Abstract: An electrical device has a housing that includes a main body and a lid both of which are electrically conductive. The lid is fastened to a top surface of a sidewall of the main body so as to cover the main body. On at least one of a bottom surface of the lid and the top surface of the sidewall of the main body, there are formed a plurality of protrusions at predetermined positions; each of the protrusions abuts against that one of the bottom surface of the lid and the top surface of the sidewall which is opposed to the protrusion. Except at those predetermined positions where the protrusions are formed, there is provided, between the bottom surface of the lid and the top surface of the sidewall of the main body, a gap via which the internal and external spaces of the housing communicate with each other.