Abstract: The present invention provides a quartz glass single hole nozzle for feeding fluid capable of performing high-precision control of a flow rate, a burner for heat processing equipped with the quartz glass single hole nozzle, a quartz glass multihole burner head for feeding fluid preferably used in flame processing or the like, and a quartz glass burner for heat processing equipped with the multihole burner. By using the nozzle, even if a distal end portion of the quartz glass burner, namely the nozzle is broken by contact with a workpiece or the like, it is enough to only replace the broken nozzle with a new one without a necessity for replacing the entire expensive quartz glass burner. When applying the nozzle to a metal burner, there can be given usefulness of the quartz glass such as heat resistance and contamination resistance or the like.

Abstract: The present invention relates to an outer-diameter blade, an inner-diameter blade and cutting machines which respectively use the outer-diameter blade and the inner-diameter blade for cutting hard material, such as metal, ceramics, semiconductor single crystal, glass, quartz crystal, stone, asphalt or concrete, and a core drill and a core-drill processing machine which drives the core drill for forming a hole in the hard material.

Abstract: A core drill having a shank and a cup shaped base metal section constructed of a disk shaped top wall and a cylindrical side wall provided on a fore-end of the shank. A grinding stone portion is mounted on an outer end part of the base metal section, with abrasive grains fixed to the outer end part of the base metal section. Abrasive grain layers are formed in a spiral pattern on inner and outer side surfaces of the cylindrical side wall of the base metal section, with abrasive grains fixed to the inner and outer side surfaces of the cylindrical side wall thereof. When the grinding stone portion is put into rotational contact with a workpiece, the workpiece is ground through to form a circle hole in section leaving a cylindrical core therein.

Abstract: Provided are an outer-diameter blade, an inner-diameter blade and cutting machines using both blades for cutting hard material, and a core drill and a core-drill processing machine for forming a hole into hard material, whereby the mechanical processing with reduction in the cutting and/or contact resistance to the tools is realized, so that in the case of the outer-diamond blade, it is prevented from occurring that a to-be-cut object is warped and put into contact to the blade to cause chipping; in the case of the inner-diameter blade, it is prevented from occurring that the blade is bowed and/or a cutting surface is curved; and in the case of the core drill, not only are grinding powder of a workpiece and loosed-off abrasive grains effectively removed to prevent those from being loaded between the drill and the workpiece, but neither of cracking and chipping occur when the drill passes through the workpiece.