| 摘要 |
This invention relates to a wrapping machine wherein one or more articles are wrapped by a shrinkable web (44) to form a package. The machine includes an article transport conveyor (22) which includes an upper article supporting run (32). The conveyor is provided at regularly spaced intervals with openings therethrough and associated with the rear of each opening is a web pulling bar (30). Articles to be wrapped are fed to the conveyor run in timed relation to the movement of the conveyor and a series of retarder bars (52), moving at a slower rate than the conveyor, pull the web down in front of each article unit to be wrapped with the article unit then bearing against the retarder bar and being slowed to the speed of the retarder bar with the conveyor moving there beneath. Following this, a clamp (54) moves down behind each article unit and first draws the web down behind the article unit and then clamps the web to the article unit. In advance of this, and before the clamp bar engages the article unit, web drawing means (146) engages the web between two adjacent article units and draws the same down into the associated openings in the conveyor and engages the web with the article pulling means. As soon as the article pulling means engages the web, the clamp bar engages the rear of the article unit and the article pulling means serves to rupture the web. Further relative movement of the conveyor with respect to the article unit results in the drawing of a trailing part of a separated web portion beneath the article unit followed by discharge rolls moving the lead part of the web portion back beneath the article unit and under the leading end of the trailing part. |
