Double-shaft rotary shaft capable of being synchronously linked

The utility model provides a double-shaft rotary shaft capable of being synchronously linked. The double-shaft rotary shaft comprises a first mandrel and a second mandrel which are parallel to each other, a first wheel body, a second wheel body and a linkage piece, wherein the first wheel body and the second wheel body are respectively sleeved with the first mandrel and the second mandrel; at least one spiral-shaped groove is formed in the peripheral side of each of the first wheel body and the second wheel body; the linkage piece comprises two parts which are in butt joint; each part comprises two concave parts and a connection part; all the connection parts are mutually and correspondingly connected; all the concave parts are mutually paired to respectively form two shaft holes of the linkage piece; the first wheel body and the second wheel body penetrate through the two shaft holes of the linkage piece respectively; at least one convex part is arranged on the inner wall of each shaft hole so as to be respe