| 摘要 |
PROBLEM TO BE SOLVED: To improve the ventilation and productivity by forming the side wall into a stepped cylinder having a reduced-diameter part and an increased- diameter part continuous through a step, opening vent from either the inner periphery or outer periphery of the step in the axial direction and releasing the molding from the die from the vent in the axial direction. SOLUTION: The main body of the accumulator is formed into a stepped cylinder having the upper increased-diameter part 28 and lower reduced-diameter part 29 continuous through a step 27. A vent 30 is opened in the step 27. The vent 30 is opened from both the inner periphery 27i and outer periphery 27o of the step in the axial direction, and the molding has a shape capable of being released from a die when formed. Since the vent 30 is axially formed in this way, the vent 30 of the accumulator is formed only by simply opening and closing the fixed die and movable core in the axial direction, and the forming cycle time is drastically shortened and productivity is improved. |
