| 摘要 |
PROBLEM TO BE SOLVED: To provide a parison expanding device for a blow molding machine wherein opening and closing positions of an expansion pin can be precisely adjusted in a stepless manner and opening and closing action can be smoothly performed. SOLUTION: Two ball screws 11, 12 are provided horizontally through support blocks 6, 6a, 7, 7a of a pair of parison expansion members 4, 4a mounted in opposition to guides 2, 3 so as to be movable back and forth, and ball screws (female) 16, 17 for engagement with the ball screws 11, 12 are provided in the support blocks 6, 7a provided in the diagonal direction, respectively, and the screws 11, 12 are rotated by servomotors 14, 15 respectively to open or close expansion pins 10, 10a of the members 4, 4a. |
