| 摘要 |
PROBLEM TO BE SOLVED: To prevent thickness unevenness of a parison in a lengthwise direction by previously compensating a thickness difference obtained from a response delay of a servo mechanism for regulating a gap between a die and a core, obtaining a pseudo-thickness pattern of the parison, and operating the mechanism based on it. SOLUTION: A target thickness pattern formed in a first memory 102 is read in a second memory 105. A voltage of a voltage generator 107 is output to a servo amplifier 25 according to this thickness signal, a position of a core is regulated, and a thickness of a parison 8 from a die head 3 is controlled. During this period, a thickness signal is output from a linear displacement meter 26, fed back to the amplifier 25, then input to a subtracter 108, then a thickness insufficient amount is output to an adder 109 to form a pseudo- thickness pattern. This is stored in the memory 105, output to an adder 109, and output to the amplifier 25 by the generator 107. Thus, thickness insufficiency generated by a response delay of a servo mechanism is compensated. |
