Reversible pneumatic drive - for blow needles of plastic blow moulding machine

摘要

Reversible motion drive for the blow needle of a blow-moulding machine for hollow plastic products, comprising a compressed air operated cylinder with a hollow piston carrying the blow needle and fitted with a spring-loaded non-return valve in the bore opening into the blow needle, the opening air pressure of this valve being set higher than that required for the prior drive of the piston to the end position of the blow needle delimited by a shoulder.