Arc surface connecting hole axis measuring device

The utility model discloses a device for measuring the axis of an arc surface connecting hole. The device comprises a laser light source, a light source fixing frame, a detection frame, a detection rod and a spherical measuring head, a connecting pipe at the lower end of the light source fixing frame is inserted into a connecting hole of the arc-surface product, and a clamping sleeve at the upper end of the light source fixing frame is used for fixing the laser light source; the detection frame is supported on the cavity wall of an inner cavity of the arc-surface product through three spherical measuring heads, the detection rod is connected in the detection frame vertical connecting sleeve through a spring, and the detection rod extends upwards under the action of the spring, so that the spherical measuring head fixed at the upper end of the detection rod tightly abuts against the cavity wall of the inner cavity of the arc-surface product; and judging whether the axis direction of each connecting hole of the