To enhance accuracy in grinding by a cutting blade by supporting a tool in a manner close to a center impeller type one even if the tool is in a bar-like shape having no center hole processed at its tip end face.
A tool support 10 is used when the tip end portion of a bar-like tool 4 mounted to the main spindle MS of a machine tool is ground, the fixture is provided with supporting parts 20, 30 and 40 supporting the mid portion of the bar-like tool 4 in such a way that the bar-like tool 4 can be rotated, and with positioning parts 44e and 44m positioning the supporting parts in such a way that the supporting parts 20, 30 and 40 can support the mid part of the bar-like tool 4 coaxially with the main spindle MS. By this constitution, when the tip end portion of the bar-like tool 4 is to be ground, the bar-like tool 4 can thereby be supported at two places, namely, at its based end part by the main spindle MS, and at the mid portion by the tool support 10. Therefore, accuracy in run-out can thereby be improved much as compared with a case that only the base end part was supported in a cantilever manner in the past, and accuracy in grinding by a cutting blade can thereby be enhanced much.
SAKABE SHUICHI