| 摘要 |
PURPOSE:To cut female thread of large diameter, or to modify a screw thread at high velocity, without using a tapping machine. CONSTITUTION:An eccentric cylinder 33 is rotatably put into a slidably rotating bush 32 which is screwed in a casing 11. The eccentricity of a main shaft 55, which is rotatably fitted to the eccentric cylinder 33 in the eccentric state, is made to be changeable, and an internal thread cutting tool 57 which is unitarily fitted to the main shaft 55 freely rotatable manner, is spirally revolved around the axis of a bush 32 which is rotating and sliding. In such a manner, a female thread, having an arbitarily large diameter, can be accurately cut at a specified pitch. In this case, driving and cutting, and feeding in and out of the cutter 57 is designed to be taken out of a spindle 13 and a drive shaft 16, but they can also be taken out from either one of these two mechanisms. |
