초록 ▼

An apparatus and method is disclosed for successively forming foam filled bags or cushions of the type wherein a foamable composition is deposited in a plastic bag. The method and apparatus includes advancing a pair of plastic webs along a substantially horizontal path of travel and through the nip

An apparatus and method is disclosed for successively forming foam filled bags or cushions of the type wherein a foamable composition is deposited in a plastic bag. The method and apparatus includes advancing a pair of plastic webs along a substantially horizontal path of travel and through the nip of a pair of drive rollers, while heat sealing the opposing longitudinal side edges of the webs together. Periodically, a predetermined amount of the foamable composition is deposited between the advancing webs from a position offset from the center of the pair of plastic webs and the heat sealing along the side edges is periodically and momentarily interrupted to form side edge openings for the subsequent escapement of gases generated during foaming. The advance of the webs is momentarily terminated, and a heated wire then engages the webs to sever the formed bag, while forming a sealed top edge of the formed bag and a sealed bottom edge for the next succeeding bag. The advance then again commences, and the cycle is repeated to successively form the foam filled bags. The offset position from which the foamable composition is deposited prevents foamable composition from splashing outside of the bags being formed.

대표청구항 ▼

An apparatus for successively forming foam cushions for packaging purposes wherein each cushion comprises a closed plastic bag filled with foam and having a ventilation opening along at least one side edge thereof for escapement of gas generated during foam formation, said apparatus comprising: supp

An apparatus for successively forming foam cushions for packaging purposes wherein each cushion comprises a closed plastic bag filled with foam and having a ventilation opening along at least one side edge thereof for escapement of gas generated during foam formation, said apparatus comprising: supply means for each of two webs of plastic film; a housing having a relatively narrow longitudinal opening therein for receiving the two webs of plastic film from said supply means, said longitudinal opening including means for guiding the webs into said housing while forming a mouth between the webs into which a foamable composition may be directed; means within said housing for advancing the two webs of plastic film along a predetermined substantially horizontal path of travel perpendicular to said longitudinal opening from said supply means and into said opening in said housing and for guiding said webs into opposing face-to-face contact; first heat sealing means positioned within said housing and along said path of travel for heat sealing longitudinal side edges of the advancing plastic webs while they are in opposing face-to-face contact; means positioned above said housing and above said longitudinal opening therein for periodically introducing a predetermined amount of foamable composition between the opposing webs, said foamable composition introducing means being positioned in a vertical plane defined by the longitudinal dimension of said opening and at an angle within said plane which is nonperpendicular to said substantially horizontal path of travel so that foamable composition deposited into each bag being formed avoids splashing directly upwardly from the mouth of the bag and instead is encouraged to splash into the bag as the webs are being advanced and sealed along said longitudinal side edges; control means for periodically and momentarily interrupting operation of said first heat sealing means to provide a ventilation opening along at least one side edge of each bag being formed to thereby allow gas generated during foam formation to escape from within each bag; and second heat sealing means positioned within said housing and along said path of travel for heat sealing said webs together transversely thereof to form a sealed top edge of a foam filled bag while also forming the sealed bottom edge of the next succeeding bag and for severing each formed bag from the next succeeding bag.