Bag sealing bar

A sealing bar for heat sealing a length of heat-sealable material, such as tubing, to form packages and the like, said bar having a surface adapted for pressure engagement with the heat-sealable material for flattening it and heating it, said bar having a slot extending substantially therethrough substantially parallel to said surface, said slot being adjacent said surface and defining the portion of the bar between the slot and said surface as a relatively thin resiliently flexible bridge which is engageable with a portion of the heat-sealable material, such as a portion of tubing having a longitudinal seam or a gusset, thicker than other portions of the flattened material, and adapted resiliently to yield on engagement with said thicker portion of the material, said sealing bar having a knife slot therein extending back from said surface substantially perpendicular to said surface for cutting of the heat-sealable material with the material being sealed at both sides of the cut, said bridge-forming slot intersecting said knife slot.

A sealing bar for heat sealing a length of heat-sealable material, such as tubing, to form packages and the like, said bar having a surface adapted for pressure engagement with the heat-sealable material for flattening it and heating it, said bar having a plurality of slots extending substantially therethrough and substantially parallel to said surface, said slots being spaced at intervals along the sealing bar and lying generally in a common plane generally parallel to and adjacent said surface, said slots defining the portions of the bar between the slots and said surface as relatively thin resiliently flexible bridges which are engageable with portions of the heat-sealable material, such as portions of tubing having a longitudinal seam or a gusset, thicker than other portions of the flattened material, said bridges being adapted resiliently to yield on engagement with said thicker portions of the material, said sealing bar having a knife slot therein extending back from said surface substantially perpendicular to said surface for cutting of the heat-sealable material with the material being sealed at both sides of the cut, said bridge-forming slots intersecting said knife slot.

A sealing bar for heat sealing a length of heat-sealable material, such as tubing, to form packages and the like, said bar having a metal surface adapted for pressure engagement with the heat-sealable material for flattening it and heating it, said bar having a slot open to atomosphere extending substantially therethrough and substantially parallel to said surface, said slot being adjacent said surface and defining the portion of the bar between the slot and said surface as a relatively thin resiliently flexible metal bridge which is engageable with a portion of the heat-sealable material, such as a portion of tubing having a longitudinal seam or a gusset, thicker than other portions of the flattened material, and adapted resiliently to yield on engagement with said thicker portion of the material, and means in the sealing bar for heating it for transfer of heat through the bar to said surface.