Abstract: A method for shrinking selected spaced apart portions of film wrapped around a series of products of similar dimension being conveyed by a conveyor along a path in a selected direction is provide. The method involves the steps of: (a) indexing the conveyor and stopping the conveyor; (b) while the conveyor is stopped, causing heated fluid to flow from one or more nozzles so that a first heated fluid flow impinges upon selected portions of film in the vicinity of a product leading edge and a second heated fluid flow impinges upon selected portion of film in the vicinity of a product trailing edge; (b) repeating steps (a) and (b) multiple times so that, for multiple instances of the product, selected portions of film along both trailing and leading edges of each instance of the product are caused to shrink.

Abstract: A method for shrinking selected spaced apart portions of film wrapped around a series of products of similar dimension being conveyed by a conveyor along a path in a selected direction is provide. The method involves the steps of: (a) indexing the conveyor and stopping the conveyor; (b) while the conveyor is stopped, causing heated fluid to flow from one or more nozzles so that a first heated fluid flow impinges upon selected portions of film in the vicinity of a product leading edge and a second heated fluid flow impinges upon selected portion of film in the vicinity of a product trailing edge; (b) repeating steps (a) and (b) multiple times so that, for multiple instances of the product, selected portions of film along both trailing and leading edges of each instance of the product are caused to shrink.

Abstract: An apparatus for controlling the operation of a packaging machine of the type which carries out the operations of causing a tube film placed around articles under transport to be cut and sealed between adjacent articles for being successively formed into bags, then causing individual bags, each with an article contained therein, to be conveyed forward by a delivery conveyor, causing the bags to be sequentially transferred from the delivery conveyor onto moving surface plates, causing each surface plate to be covered with a cover member, and then causing the interior of the cover member to be placed under a vacuum atmosphere while the open end of the bag is hermetically sealed. A bag sensor sequentially detects the passage of open ends of bags on the delivery conveyor, and a surface plate detecting sensor sequentially detects the passage of individual surface plates.

Abstract: There is disclosed an apparatus for use in a bag forming/filling/sealing machine for controlling the operations of a film transportation motor, an article feeding motor, frame driving motor and a sealer opening-closing motor, wherein rotations of the film transportation motor and the article feeding motor are controlled based on the rotation of the frame driving motor. The rotation cycles of the film transportation motor, the article feeding motor and the frame driving motor are determined based on a reference pulse which is generated by a crystal oscillator and inputted to a central processing unit. When a value of the length of articles to be packaged is inputted to the central processing unit, the central processing unit specifies a cyclic variable speed of the frame driving motor based on data stored in a memory.

Abstract: The present invention is intended to effect proper sealing of a film by automatically adjusting the gripping pressure exerted by seal bars on the basis of a change in unsteady current flowing through the seal bars which grip the film. When the main shaft of a servomotor mounted on a frame is rotated forward and backward, the pair of seal bars opens and closes. When the seal bars press each other, the film is gripped under pressure by these seal bars and heat-sealed. Cushion means for elastically pressing the seal bars increases the gripping pressure of the pair of seal bars in proportion to an increase in the angle of rotation of the motor main shaft after the opposed surfaces of the seal bars have contacted each other.

Abstract: There is disclosed an apparatus for use in a bag forming/filling/sealing machine for controlling the operations of a film transportation motor (10) and an article transportation motor (18) based on the operation of a sealer driving motor (25) which is driven at a cyclic variable speed. The rotation cycles of the respective motors (10, 18, 25) are determined, based on a reference pulse which is generated by a crystal oscillator (28) and input to a central processing unit (27). When a value of the length of articles (19) to be packaged is input to the central processing unit (27), the central processing unit (27) specifies constant speeds of the film transportation motor (10) and the article transportation motor (18) and a cyclic variable speed of the sealer driving motor (25).

Abstract: An apparatus for packaging articles in deaerated condition. A belt-like film is tubulated to enclose a plurality of articles transported in a longitudinally aligned fashion. The articles and the film are transported together in integral relation while the air in the tubular film is evacuated by a pipe nozzle inserted in the film tube. The pipe nozzle is connected to a vacuum source via a connecting pipe. Usually, the interior of the tubular film is kept in a suitable negative pressure condition by suction through a tube bypassing a normally closed valve disposed on the connecting pipe. The valve is impulsively opened immediately before seal bars press the film from opposite sides so that the air in the film is instantly discharged.

Abstract: An improved packaging apparatus comprising; a pair of endless belts 70 and 70 which respectively nip a tubular film 63 at a downstream domain of a frame body 14 which is capable of reciprocating itself in order to support a pair of sealing bars 65 and 66 for sealing a tubular film 63 used for covering a number of packageable individual contents 46 being conveyed in file; two pairs of pulleys 73 and 74 which respectively support a pair of belts 70 secured to a supporting plate 71 connected to the frame body 14; and a pair of bevel gears 80 and 80 which link an idle shaft 79 having own axis horizontally being secured to the supporting plate 71 by means of a pair of shafts of those pulleys 73 and 74 engaged with a pair of endless belts 70 and 70. An endless chain 86 links a chain wheel 86 secured to the idle shaft 79, a pair of chain wheels 84 and 85 secured to the frame body 14, and a pair of chain wheels 82 and 83 secured to the frame body 14, with each other.

Abstract: A packaging machine of the type having a mechanism for tubulating a belt-like film and a conveyor for transferring products into the tubular film is typically equipped with a pair of sealing bars which produce transverse seals between the products being packaged. The present invention relates to a mechanism which is able to control the length and speed of the stroke of the sealing bars and the speed of the film dependent on the length of the product being packaged which assures more uniform heating of the seals resulting overall in more uniform transverse seals.