摘要 |
A cooling device of an injection mold for an optical disk substrate reduces the chances of cavitation caused by a turbulent flow of passing cooling water, thus enabling a disk cavity plate to be cooled uniformly. A plurality of main arc-shaped passages, which have the same cross-sectional shape and which are concentrically arranged, are provided at a pitch "p" from the inner circumference on the rear surface of the disk cavity plate of the optical disk substrate injection mold. Further provided are a connecting arc-shaped passage having a radius of "p" which connects a first main arc-shaped passage having a radius of R1 with a second main arc-shaped passage having a radius of R2, and the centerline of which is tangentially connected to the second main arc-shaped passage, and which has the same cross-sectional shape; and a connecting segment-like passage, the centerline of which is tangentially connected to the connecting arc-shaped passage and the first main arc-shaped passage having the radius of R1, and which has the same cross-sectional shape. In a similar manner, main arc-shaped passages are connected one after another to constitute the cooling device of the injection mold for the optical disk substrate. <IMAGE> |