Disclosed in the present invention are a combined machine head and a ray imaging device. The combined machine head comprises: a housing, having an enclosed cavity; a ray bulb tube, provided in the enclosed cavity; a pump body and a pipe body, provided in the enclosed cavity; the pump body being provided on the side away from the positive electrode of the ray bulb tube, one end of the pipe body being connected to an outlet of the pump body, and the other end extending to be near the positive electrode of the ray bulb tube; or, the pump body being provided near the positive electrode of the ray bulb tube, one end of the pipe body being connected to an inlet of the pump body, the other end extending to the side away from the positive electrode of the ray bulb tube. In the present invention, when the pump body operates, the insulating medium at the positions away from of the positive electrode can be drawn to be near the positive electrode, and the insulating medium in the enclosed cavity is driven to be circulatory, thereby gradually decreasing the temperature difference between the position of the positive electrode and the other positions, further enabling the temperature gradient of the insulating medium in the enclosed cavity to be distributed more uniformly.