Positioning mechanism of auto-rotating board turnover machine

The invention discloses a positioning mechanism of an auto-rotating board turnover machine, which specifically comprises an extension mechanism and a positioning plate, wherein the extension mechanism is fixed on a stander of the auto-rotating board turnover machine; the positioning plate is fixed on a rotating part of the auto-rotating board turnover machine; and a positioning hole matched with an extension bar of the extension mechanism is reserved on the positioning plate. In the embodiment of the invention, the extension mechanism is fixed on the stander of the board turnover machine, the positioning plate is fixed on the rotating part of the board turnover machine, and the positioning hole matched with the extension bar of the extension mechanism is reserved on the positioning plate. As the extension mechanism is fixed on the stander and cannot rotate, while the positioning plate rotates with the rotating part, and the rotation of both the positioning plate and the rotating part can be simultaneously limited when the extension bar is extended into the positioning hole, the rotating part can be instantly and stably stopped after the rotation to shorten board turnover time and improve efficiency.