Shank switching device for BT60 spindle on lathe

The invention discloses a shank switching device for a BT60 spindle on a lathe. The shank switching device comprises a mounting mechanism and a hollow switching shank. The switching shank is composed of a truncated cone part and a cylinder part. A switching conical hole and a switching shaft hole are formed in the switching shank. A BT50 broaching tool claw and a BT50 broaching tool claw fixing block are arranged inside the switching shaft hole. A first protective cover is arranged on the outer side of the BT50 broaching tool claw and the BT50 broaching tool claw fixing block in a sleeved mode. A second protective cover is arranged on the outer side of the first protective cover in a sleeved mode. The second protective cover is connected to the switching shank in a threaded mode. The second protective cover is provided with a conical part, wherein the conicity of the conical part is the same as that of the truncated cone part. A spring is arranged between the first protective cover and the second protective cover, and arranged on the outer side of the first protective cover in a sleeved mode. The shank switching device is convenient to install and use, enables a BT50 tool to be applied to the BT60 spindle on the lathe, reasonably expands the machining range of the lathe, reduces labor intensity of an operator when a BT600 tool is replaced, and improves machining efficiency of the lathe.