Abstract: Apparatus for heat sealing a pair of hems in a moving web of film having structure including a pair of spaced surfaces over which each hem of the pair of hems is adapted to pass. A first block is supported by the structure with respect to one of the surfaces and on one side of one of the hems. A plurality of rollers is mounted on the first block at spaced locations in tandem for engaging the film along the path of the heat seal to be formed in the one hem. A second block is supported by the structure with respect to the other of the surfaces and on one side of the second hem. The second block has a plurality of rollers mounted thereon at spaced locations in tandem for engaging the film along the path of a heat seal to be formed in the second hem. Heaters are provided for each of the blocks and the respective plurality of rollers whereby movement of the hems through the heat sealing apparatus causes the plurality of rollers mounted on the blocks to rotate and produce the heat seals in the pair of hems.

Abstract: Draw tape bags are made with folding surfaces which decrease in width to the final bag height. One edge of each side of a moving web of film is tucked onto a side of a surface to produce a hem in each edge of the moving web. Rollers, which are canted with respect to the direction of movement of the web, pull the hem of the film tight against the surface to insure that the web is at the final bag length when the web leaves the surfaces.

Abstract: A thermoplastic draw tape having thick and wide end portions with a relatively thin and narrow central portion between them is produced by movable clamps which stretch the tape between stationary clamps to produce the stretched, oriented portions of the tape. A plurality of movable clamps and a plurality of stationary clamps produce a plurality of stretched central portions so that the stretching time can be greater than the cycle time of bag making machinery with which the stretching apparatus is synchronized.

Abstract: A method and apparatus for forming draw tape bags wherein the bag material moves continuously during the manufacture, except for the last step. A roll of folded web is provided, and the loose edges are turned inwardly to form upper hems for the bags. The web continues to move, and a cutter is actuated to move through a circle and engage the web to punch finger holes in the hem. The web is further carried to a tandem sealer, the web passing over a roll where heated air is directed at the area of the hem. A "Teflon" strip is placed between the hems to prevent sealing them together. The web continues to a second sealing roll where the opposite side is sealed in the same way. The final step utilizes a stop-start apparatus with a side sealing blade. The side sealing blade has one radius for the body of the bag, and a larger radius for the hemmed area.

Abstract: A thermoplastic draw tape for bags is produced by stretching thermoplastic between a first pair of nip rollers running at a relatively slow speed and a second pair of nip rollers running at a higher speed. A rotating cylinder has hot and cool sections spaced around the circumference. The draw tape is heated in intermittent sections which are stretched as they pass through the nip rolls to produce a relatively thin and narrow central portion between end portions which pass over the cool sections of the rotating cylinder.

Abstract: A draw tape for thermoplastic bags is made by feeding tape to a first pair of nip rolls rotating at a relatively slow speed and a second pair rotating at a fast speed. The tape is stretched to form thin and narrow central portions between end portions of unstretched tape. The first nip rolls are increased in speed, or are released to interrupt the stretching. When the rolls are closed, one of them is momentarily retarded or backed up, to produce a rapid transition in the tape between the unstretched end portion and the stretched central portion.

Abstract: A thermoplastic tape having thick and wide end portions with a relatively thin and narrow stretched central portion between them is produced by a first pair of nip rolls running at a slow speed, and a second pair of nip rolls running at a higher speed. The tape between the nip rolls is intermittently moved away from, and toward said first nip rolls to stretch it to produce the relatively thin and narrow central portion. The second pair of nip rolls is mounted on a pivoted arm so that they are movable toward, and away from said first nip rolls. Alternatively, an idler roll between the two pairs is moved toward, and away from, the first nip rolls.

Abstract: Draw tape bags have a high molecular weight, high density polyethylene draw tape which is intermittently stretched so that the tape has central portions of relatively narrow and thin oriented polyethylene and end portions which are relatively wide and thick. The end portions are heat sealed to the sides of the bag panels to secure them. The stretching makes the tape cost more economical and improves the break characteristics while the thick and wide end portions permit good heat sealing without weakening the draw tape. Also disclosed is a method of making such bags.

Abstract: A method of forming plastic film bag bodies with draw strips comprises the steps of providing a continuous length of plastic film once folded to provide superposed panels and two free longitudinal edges opposite a fold edge, folding the two longitudinal free edges inwardly between the adjoining panels to provide a pair of longitudinal inwardly turned hems of double thickness, inserting a continuous material draw strip into each hem, joining together longitudinally the double layer thicknesses of each hem to form a channel along a longitudinal edge of each panel containing one of the continuous strips and transversely severing the material and strips at regular intervals to separate individual bag body lengths from the continuous web of material. Holes are punched along the folded hems of the bag before the draw tapes are inserted so as to allow access to the inserted tapes in the manufactured bag.

Abstract: Thermoplastic tape is stretched by a rotating disk having slots extending radially outward from the center of rotation of the disk. The tape is gripped by clips which are moved outwardly in the slots by a cam slot as the disk rotates. The clips grip the tape throughout a length which forms relatively thick and wide unstretched portions of tape with relatively thin and narrow central portions of stretched tape between said clips.

Abstract: A method of inserting a continuous, pliable strip into each hem formed along an edge, an edge of one of a pair of superposed panels forming an elongated, continuous web, the hem being formed by turning an edge portion of a panel inward between the panels. Each strip is fed from a position outside the web on the hemmed side of the web, across the hem(s) to a position between the panels within the web, reversed in direction and fed to a position between the portions of the panel forming a hem. Each strip is then turned from a transverse direction to a longitudinal direction and fed longitudinally into the hem. An apparatus for performing the steps of the method is described for use in the manufacture of thermoplastic film draw strip bags and feeds a pair of extremely thin and flexible plastifilm strips into a pair of hems, each formed in one of a pair of superposed panels, eventually forming the sides of the finished bag.

Abstract: A method of making a combination knockdown handbag and mat from a blank of readily foldable sheet material by reversely folding a portion of the sheet onto a portion of the blank and securing the reversely folded portion onto the adjacent portion of the blank to define one or more open end pockets. In the unfolded position thus formed, the blank defines a mat with one or more pockets formed at one end. To convert the mat into a handbag, the extended portion of the blank is folded in an accordian fashion one or more times to the size and shape of the reversely folded portion. The blank thus folded is reversely folded about a central portion thereof, and the pocket formed is turned inside out so that the accordian folded extended portions are disposed within the pocket turned inside out to define the handbag. A handle may be secured to the pocket to facilitate the carrying of the handbag in the folded position of the blank.

Abstract: A draw tape trash bag made of linear low density polyethylene film has a tack seal between the folded over hem portion of the top of the bag and the adjacent panel. The tack seal extends in the direction of extrusion across the width of the bag below the draw tape. It includes a continuous line of heat fused polyethylene formed by applying heat, but limited pressure, in an amount just sufficient to weld the polyethylene.

Abstract: A drawstring is mounted near the open mouth of a plastic bag by a pressure sensitive tape that freely laterally encloses the drawstring except for projecting free ends, the tape being formed or treated so as to be non-sticky with respect to the drawstring. A high speed production method of making the bags comprises the steps of laying a continuous length of drawstring material across a series of spaced bags, applying strips of pressure sensitive tape to each bag to freely laterally enclose the drawstring length there and severing the drawstring length between bags.

Abstract: The present invention relates to a method of manufacturing bag-like packages of flexible material, in which each package is so arranged as to have a number of closure ribbons (38, 48). A blank belt (1) which is essentially double-folded in its longitudinal direction is divided into a number of consecutive, bag-like packaging blanks (7). A number of closure ribbons (38a, b and 48a, b) extend through similarly located channels in all the packaging blanks. The ribbons are shortened in their longitudinal direction, for instance by folding. The blank belt is moved over guide devices (6a, b) which open the packaging blanks at the same time as the distance between their openings (32", 32"') increases. This causes drawing out of sections of the closure ribbons (38, 48) from the channels in the adjacent packaging blanks. The drawn-out closure ribbons are attached to each other in pairs and are cut off at the areas of attachment so as to form endless closure ribbons for each and every one of the packaging blanks.