| 摘要 |
Cigarette filter units are made in a long strip with alternate portions of fibrous and pourable filter material. The fibrous portions are first attached at spaced intervals to a sheathing strip which is wrapped practically right around them to form a cylinder with regular empty spaces between the fibrous portions and openings into the spaces. In a special unit, air is extracted from these spaces so that when the spaces enter a chamber containing pourable filter material, they suck the material in to fully fill the spaces. Excess filter material is brushed off the filter unit, and a sealing strip is stuck over the openings.
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