Plane-rotating automatic-locking quick-changing positioning device

The utility model discloses a plane-rotating automatic-locking quick-changing positioning device, which comprises a positioning supporting frame. The upper surface and the lower surface of a top cross beam of the positioning supporting frame are respectively provided with a supporting block and an air cylinder. A fixed pin facing upwards is vertically arranged on the upper surface of the supporting block. The top of a piston rod of the air cylinder is fixedly connected with a jacking shaft; the top shaft passes upwards through a key-groove shaft hole arranged at the middle of the supporting block in a dynamic cooperative way; a rotating supporting block is slidably arranged on the upper surface of the supporting block. The upper end of the ejecting shaft and the shaft hole at the middle of the rotating supporting block are sleeved with each other in a rotatably-matching way. A plurality of positioning mechanisms are evenly distributed on the upper surface of the rotating supporting block at equal radius around the jacking shaft. A fixed hole slidably matched with the fixed pin is arranged on the rotating supporting block. The advantages are as follows: accurate positioning, rapid disassembling and fastening are realized for a type-changing mechanism; the error of type-changing is smaller than 0.1 mm; the switching time is less than 1 minute; the production efficiency is greatly increased; and multi-types collineation production is realized.