Simple and accurate pay-off hole pre-embedded trepanning positioning device

The utility model discloses a simple and accurate pay-off hole pre-embedded trepanning positioning device. The device is composed of two parts. The upper part comprises an inverted double-circular-truncated-cone-shaped laser projection cylinder, the inverted double-circular-truncated-cone-shaped laser projection cylinder is of a structure with an upper layer and a lower layer, the upper layer is cylindrical, the lower layer is circular-truncated-cone-shaped, the upper layer is hollow and is provided with an infrared laser projection head and a battery, and a level bubble is embedded in the circular-truncated-cone-shaped surface of the lower layer; a cylindrical double-ring-shaped leveling base is arranged at the lower part and is provided with an adjusting bolt. The device disclosed by the utility model can be repeatedly used, and is simple to manufacture, easy to operate and high in precision, so that the construction operation time is shortened, and the number of operators is reduced. Compared with a conven