October 12, 2004

An internal bubble cooling air control system in a blown film apparatus has sensors arranged to increase response time and reduce interference, and includes a high speed valve for fast actuation of air flow from a controller in response to signals received from the sensors.

27

October 12, 2004

10/425,418

April 29, 2003

264/40.3   264/40.6 264/564 425/141 425/326.1

B29C   47/92   (20060101)   B29C   47/88   (20060101)  

CROSS REFERENCE TO RELATED APPLICATION This application is a continuation of application Ser. No. 09/746,885, filed Dec. 21, 2000, now U.S. Pat. No. 6,562,263.

425/326.1   425/141   425/72.1   425/174.2   264/40.3   264/40.6   264/564   264/565   264/407