PURPOSE: To shorten a working time and to improve the accuracy in detecting a temp. by detecting the temp. of the bottom face of the bottomed hole reaching up to the cavity vicinity of a die pierced on the outer face of the die by the camera for detecting a radiation temp.

CONSTITUTION: A cavity 9 is formed by fixed die 5 and moving die 6. The water amt. relying on the opening and closing operation of motor valves M1, M2 by passing through flow path 10, 20 is fed to cooling chambers 10A, 20A respectively. Bottomed holes 1, 2 are pierced so as to have an opening at the position surrounded by the cooling chambers 10A, 20A, a heat insulating material 8 is peripherally provided on the outer peripheral face of a pipe 7 and these are buried in the hole 1, 2. The camera 11 for detecting radiation temp. is then arranged at the position having the visual field angle θ including the holes 1, 2 in the visual field by opposing to a face 5A, measuring the temp. of the bottom face of the hole 1 at the vicinity of the cavity 9 by the camera 11 by detecting the heat ray reflected until the hole 1 opening part. The observed value and reference value are compared by a camera control device 15 and the valve 1 is opened and closed to control the die temp.