Abstract: A machine and method for making bags is described and includes a web traveling from an input section to a rotary drum, to an output section. The rotary drum includes at least one seal bar, having a first sealing zone, and an adjacent weakening zone. The weakening zone may be a heated perforator, includes a heating wire, or be disposed to create an auxiliary sealed area. The heating wire can have, connected thereto, a source of power that is at an adjustable voltage or magnitude, and/or pulsed, and/or a feedback loop. The heating wire may be an NiCr wire and make intermittent contact with the web and be disposed in an insert. The weakening zone may create a line of weakness that is uniform or varies in intensity, is a separating zone, or includes a heat film, a toothed blade, a row of pins, a source of air, or a source of vacuum. The sealing zones may include temperature zones, cartridge heaters, cooling air, or heated air, or a source of ultrasonic, microwave or radiative energy.

Abstract: A machine and method for making bags is described and includes a web , traveling from an input section to a rotary drum, to an output section. The rotary drum includes at least one seal bar, having a first sealing zone, and an adjacent weakening zone. The weakening zone may be a heated perforator, includes a heating wire, or be disposed to create an auxiliary sealed area. The heating wire can have, connected thereto, a source of power that is at an adjustable voltage or magnitude, and/or pulsed, and/or a feedback loop. The heating wire may be an NiCr wire and make intermittent contact with the web and be disposed in an insert. The weakening zone may create a line of weakness that is uniform or varies in intensity, is a separating zone, or includes a heat film, a toothed blade, a row of pins, a source of air, or a source of vacuum. The sealing zones may include temperature zones, cartridge heaters, cooling air, or heated air, or a source of ultrasonic, microwave or radiative energy.

Abstract: A method and apparatus for detecting seals on a film from which bags are formed includes a force transmitter and a force sensor. The force transmitter transmits a force from the film to the sensor. The force sensor receives the transmitted force and provides a force signal. A controller receives the force signal and provides a seal signal. The the force sensor may be an mechanical sensor, an acoustic sensor, a mechanical sensor, a vibration sensor or a piezoelectric sensor.

Abstract: A heat sealing/severing device for heat sealing thermoplastic films together. The device includes front and rear opposing jaws that are moveable between an open position and a closed position. The open position defines a zone for inserting the thermoplastic films between the front and rear jaws. In the closed position, the front and rear jaws are proximate each other to compress the thermoplastic films together. The rear jaw includes a resilient portion facing the front jaw. The heating element of the device may have a cross-sectional thickness no less than 0.55 times the cross-sectional thickness of the resilient portion. A front jaw release sheet (e.g., an unreinforced fluoroplastic) may be positioned between the insertion zone and the heating element. The front jaw release sheet may engage the heating element when the front and rear jaws are in the closed position and disengage from the heating element when the front and rear jaws are in the open position.

Abstract: The present invention relates to a sealing apparatus for sealing foil material, the apparatus comprising a foil conveying means and a sealing means including a sealing head which has at least one sealing position for performing the foil sealing operation, an intermediate position in which the sealing head has a predetermined distance from the sealing position, and an inoperative position in which the sealing head has a second predetermined distance from the sealing position that is greater than the first distance. Furthermore, the invention relates to a corresponding sealing method which can be carried out with the sealing apparatus, wherein the sealing head is removed from the foil material to a first distance during the further transporation of the foil material and is removed from the foil material to a second greater distance when the foil sealing operation is interrupted.

Abstract: In an apparatus for machining a material web by means of a sonotrode, the pressure force of the sonotrode is determined and is used as a control signal for the advance of the sonotrode, as a result of which the nip height is set.

Abstract: A seal bar assembly which includes a support structure (21), and at least a first seal bar segment (22) and a second seal bar segment (23) mounted substantially parallel to each other on the support structure. The seal bar segments define a gap (28) therebetween. Each seal bar segment has two ends, with mounting means (26) positioned proximate to each end of both the first and second seal bar segments for mounting the ends of the seal bar segments to the support structure. The mounting means are adapted to permit one or both ends of each seal bar segment to move toward or away from the support structure, but the mounting means do not permit the seal bar segments to significantly move transversely with respect to each other. In this manner, the seal bar segments remain substantially parallel to each other, and the gap between the seal bar segments is maintained substantially constant.

Abstract: An apparatus is described for welding the sealing seam (23) on a package (24) and which consists at least partially of synthetic plastics coated paper, with a welding tool comprising dies (25, 28) and counter-dies, a support and a drive means (1) for generating the pressure force.So that two welding tools (25, 25a) can be used and operated simultaneously and so that substantially the same pressure forces are available at both working stations, it is according to the invention envisaged that two welding dies be mounted on respective outer hollow shafts (7, 9) in such a way as to be rotatable about a common axis (2), each outer hollow shaft (7, 9) being rotationally rigidly connected to a common torsion spring (3) as part of the drive means (1) (at 14, 16, 17), the torsion spring (3) being driven from outside (at 11, 12).

Abstract: An apparatus and method for manufacturing reclosable thermoplastic containers which eliminates the need for spot-sealing zipper closures or zipper closure elements to a web of thermoplastic film prior to forming side seals and zipper end seals is provided. Opposing seal jaws provide increased heat and pressure to zipper closures in a manner which results in improved hermetic and fluid-tight side seals and zipper end seals.

Abstract: An improved thermoplastic film heat bonding apparatus includes a heated seal bar, a support member supporting the heated seal bar for reciprocating motion against a platen and a resilient coupling between the support member and the heated seal bar to allow deflection of the heated seal bar with respect to the support member providing better conformance between the platen and the face of the seal bar contacting the platen for more uniform and repeatable heat seals. Springs are used to provide the resilient coupling between the support member and the heated seal bar. One mounting providing both resilient coupling and continuous adjustable spacing between the support member and the heated seal bar includes a bracket supporting a threaded member passed through the support member and a coil spring biasing the bracket and support member apart. The bracket is itself resiliently mounted to the heated seal bar also by compression coil springs.

Abstract: Apparatus for severing bags from a two-ply web of thermoplastic material. The apparatus includes web guide rollers defining a nip, and a plurality of peripheral grooves in the guide rollers in which upper and lower air directing tubes are positioned to guide a web as it passes downstream of the feed rollers. A continuously transversely moving severing knife is provided downstream of the feed rollers and below the plane defined by the moving web. A pair of welding jaws are provided adjacent the cutting knife to grip the web in a plane below the web movement plane to weld the plies of the web together and to deflect the web into position for providing a transverse cut therein by means of the severing knife. A pivot lever is provided to pivot downstream ends of the lower air directing tubes in a downward direction to prevent interference between the downwardly deflected web and the downstream ends of the air directing tubes.

Abstract: To provide for uniform pressure, under predetermined conditions, of application of closure sealing jaws for a bag making machine, to close thermoplastic tubular foils, a hydraulic pressure element (7;26,28) applies the pressure of a pressure jaw (1) against another (2), with the foil interposed; the hydraulic pressure is sensed by a transducer (11), converted into an electrical signal and compared with a command set signal (22), any error or deviation being fed back in a closed loop to a servo positioning valve (13,15) to thereby set the hydraulic pressure with which the movable jaw (1) is applied against a fixed jaw (2) in accordance with commanded value.

Abstract: A sealer is disclosed for sealing upper and lower portions of a web without sealing the portions together, such as side gussets in side gusseted bags. A sealing bar is placed below the web and fixed with respect to the machine. Another sealing bar is placed above the web, parallel to the first one. An air cylinder can urge the upper sealing bar down against the lower one to seal the web. A platen is placed within the side gusset to prevent the portions from being sealed to each other, and the platen floats vertically to accommodate the motion of the sealing bars.

Abstract: An improved L-sealing apparatus providing an L-shaped sealing bed assembly mounted at its ends and corner on three piston-and-cylinder assemblies operable upon closing of the sealing arm into adjacency with the sealing bed assembly to translatorily move the sealing bed assembly into uniform and continuous surface contact and pressure with the heating wire arrangement of the sealing arm. In another embodiment, the sealing bed assembly is fixed to the machine frame and a pair of pneumatic-electromagnetic latching assemblies are provided to magnetically engage the sealing arm at its opposite ends in its sealing disposition adjacent the sealing bed assembly to torsionally distort the sealing arm if and as necessary to bring its wire heating assemblies into parallel continuous and uniform surface contact and pressure with the sealing bed assembly.

Abstract: Opposed strips of heat-sealable thermoplastic strips are advanced along a path past a pouch-forming and incomplete cut-out zone, a filling zone and a pouch-sealing and cut-off zone. Each incompletely cut-out pouch has a spout whose open end extends to opposed marginal bands of the strips. Nozzles are projected into the spouts at the filling zone. A tight fit of the nozzles in the spouts prevents escape of fluid around the nozzles during the filling operation. The marginal bands of the strips are gripped adjacent each spout to enable the nozzles to be pushed into the spouts. The filled pouches settle onto a conveyor while the marginal bands hold the open ends of the spouts at a higher level, preventing discharge of fluid from the spouts until the filled pouches are sealed. Sufficient height of the spout opening above the mean level of the filled body of each pouch tends to form a discharge-blocking pinch across the spout, and a still-higher level of the spout opening prevents the discharge of fluid by gravity.