| 摘要 |
Apparatus for heat shrinking pre-oriented polyolefin plastic sleeves over the outer surface of a glass bottle. The bottles with sleeves in position thereon are gripped and suspended from rotatable chucks spaced along a movable conveyor means extending through an oven. The oven is constructed with a first zone of infrared burners directed at the mid body of the bottles and a succeeding second zone of infrared burners in upper and lower placement are directed at the neck and heel portions of the bottle, respectively. During travel past the burners, the bottles and sleeves are rotated at controlled speed to prevent collapse of the sleeve as it becomes heated. Opposite the burners is an exhaust section of the oven having plural sets of damper means, each set controlling air flow in plural vertically spaced horizontal rows of exhaust ports along the length of the oven. Air is drawn across the oven and over the conveyor chucks to aid directing heat on the sleeves and cool the chucks. The exhaust section includes fan means for drawing air in and over the oven through the ports and to an exhaust stack. The burners are mounted for vertical and angular adjustment with respect to the path of the bottles in the oven. The first zone of burners heats the annular mid part of the sleeve and shrinks that part firmly on the bottle body; and, through the control of exhaust air, some heat is applied to the upper portion of the sleeve, and by the same means, heat is kept from the lower portion. The second zone of burners adds enough heat to shrink the upper part of the sleeve onto the neck of the bottle, plus heat and shrink the plastic in the lower portion of the sleeve onto the heel and bottom of the bottle, but heat is directed so as not to damage the surface of the shrunken mid portion. High production rates are experienced with a relatively short span of oven utilizing the apparatus, and a superior finish of wrap over the outer surface of the bottle is achieved. |
