| 摘要 |
PURPOSE:To make improvements in productivity promotable, by setting up each of grindstones, one for superfinishing use and the other coarser than the former, at plural spots on a peripheral surface of a tool head retractably in a separate manner from each other, in case of superfinishing for a crankshaft or the like. CONSTITUTION:A work W is inserted into the inside of a tool head 1, and first of all, each coarse-grained second grindstone 62 is pressed to the work, rotating the work W and grinding its pheripheral surface to the extent of fixed grinding depth, then each first grindstone 61 for superfinishing use is advanced forward for pressing it to the work, making second stones 62 go back, thus superfinishing takes place. Here, both these stones 61 and 62 are advanced or retracted along a radial contact surface (a) passing an axial center 0 of the work W so that ech of retractable axes X themselves will not pass the axial center O but there is no particular hindrance, and when the first stone 61 is installed in the rear in a work rotational direction of the contact surface (a) and the second stone 62 in the front parallely, good grinding is performable. Thus, the tool head is made into contact in size and, what is more, superfinishing grinding is performable favorably in terms of productivity. |
