US 5,645,789 A · Distensible pet balloon and method of manufacture

Abstract

A semi-compliant PET balloon and a method for manufacturing the balloon are disclosed. The method for manufacturing the semi-compliant PET balloon includes the steps of varying the temperature and inflation pressure on a tube of PET material in an ordered sequence to i) form the balloon, ii) thin the walls of the balloon, ii) size the balloon and then, iv) crystallize the PET material of the balloon. First, to form the balloon, the tube of PET material is preheated, and simultaneously pressurized and stretched. The pressure in the tube is then increased to conform the balloon to the shape of a mold. Next the balloon walls are thinned by decreasing pressure and providing additional stretch on the PET tube. A subsequent increase in pressure sizes the balloon. The sized balloon is next subjected to an increase in temperature and a decrease in pressure to crystallize the PET material. A cooling step completes the method for manufacture.

Claims18

Dependent claims

A method for manufacturing a semi-compliant polyethylene terephthalate (PET) balloon which comprises the steps of:

positioning a tube of PET material across a mold cavity, said tube having a lumen extending therethrough;
preheating said tube in said cavity to a first temperature to soften said PET material;
pressurizing said lumen to a first pressure;
stretching said tube a first predetermined distance to lengthen said tube;
forming said balloon by raising said first pressure to a second pressure;
thinning said balloon by decreasing said second pressure to a third pressure and additionally stretching said tube a second predetermined distance;
sizing said balloon by increasing said third pressure to a fourth pressure;
crystallizing said PET material of said balloon by decreasing said fourth pressure to a fifth pressure and increasing said first temperature to a second temperature;
and
cooling said PET material of said balloon by decreasing said second temperature to a third temperature.

7 more elements

Dependencies are inferred from the claim text.

Distensible pet balloon and method of manufacture

Life of this patent

Distensible pet balloon and method of manufacture

Life of this patent

Abstract

Claims18