Appratus for sealing and severing a web of film

An apparatus for sealing and severing a web of film comprising:

• a sealing bar having a body portion including first and second sidewalls and a top portion for melting and severing a portion of the web of film, the top portion including first and second sides extending upwardly from the first and second sidewalls at an acute included angle .phi. with respect to a plane that is parallel to a plane defined by the web of film as it is fed to the apparatus for sealing and severing;
• a holder for holding the sealing bar, the holder including a first side and a second side that define a center region for receiving the body of the sealing bar, the first and second sides each including shoulders;
• insulating walls located in the center region for insulating the sealing bar from the holder;
• the shoulders, top portion of the insulating walls, and top portion of the sealing bar defining means for substantially limiting the creation of a resultant bead in the film during the sealing and severing process;
• and
• a backup member, located on an opposite side of the film from the sealing bar and diametric thereto, for urging the film against a portion of the sealing bar, insulating walls, and shoulders.

An apparatus for sealing and severing a web of film comprising;

• a sealing bar having a body portion including first and second sidewalls and a top portion for melting and severing a portion of a web of film, the top portion including first and second sides extending upwardly from the first and second sidewalls at an angle .theta. of approximately 30.degree. to about 75.degree. with respect to a plane that is substantially parallel to a plane defined by the web of film as it is fed to the apparatus for sealing and severing;
• a holder for holding the sealing bar, the holder including a first side and a second side having first and second sidewalls that define a center region for receiving the body of the sealing bar, the holder including insulating walls for insulating the sealing bar from the holder, the first and second sides of the holder each including a shoulder extending from the center region at an angle of approximately 0.degree. to about 90.degree. with respect to the plane substantially parallel to the plane defined by the web of film;
• and
• a backup member, located on an opposite side of the film from the sealing bar and including means for exerting a pressure against a web of film to be sealed and severed over substantially the entire face of the sealing bar and insulating walls and a portion of the shoulders.