Abstract: This invention relates to apparatus for making plastic material bags from an intermittently advanced, flattened tubular film web comprising retaining means which in the direction of advance of the tubular film web succeed transverse cutting means and serve to retain adjacent to its open end rim the last bag which has been severed from the tubular film web. To provide such apparatus which is structurally simple and can be used to make imperforate bags, the retaining means consist of a suction box (32), which adjacent to the transport plane is provided with suction holes arranged in two rows (33, 34), which extend transversely to the direction of travel and have a spacing which is approximately as large as the pitch of the shingled groups of bags. A pressure roller (35) which is adapted to be raised and lowered is adapted to be lowered onto the last bag which has been deposited and cooperates with a backpressure roller (37), which is disposed under the upper course of the conveyor belt (5).

Abstract: The invention relates to stacking flat articles, such as tube sections, bags or sacks, with two spaced apart hubs arranged to rotate in synchronism on a horizontal axis and carrying respective spiders, the arms of which are equally angularly spaced and on their leading sides, in the sense of rotation, carry suction nozzles, with a receiving or carrying conveyor for the article disposed between the arms adjacent to the horizontal plane which contains the horizontal axis and protrude beyond the articles to such an extent that the side edges of the articles extend, at least in part, to the planes in which the arms are rotatable. A series of needles are disposed on the side of the axis which is opposite to the receiving conveyor and are closely spaced from the arms of one of the spiders and extend approximately parallel to that one of the arms which is in a vertical position, to enter perforations of the articles as the articles are delivered by the arms.

Abstract: Flattened tube sections for making sacks are continuously supplied by a main conveyor and selectively fed longitudinally to one of a plurality of connecting conveyors leading to respective production lines along which the sections are moved transversely after turning by respective turntables. The connecting conveyors for the second and subsequent production lines receive their tube sections from an intermediate conveyor. A deflector is pivotable between the intermediate conveyor and the connecting conveyor for the first production line.

Abstract: In a method of stacking sacks of thermoplastic film, the sacks are successively deposited on each other and formed with internested loops of progressively shallower depth.

Abstract: In a stacking apparatus for flexible sheets comprising a chain conveyor consisting of two spaced chains running over sprockets at the delivery end, each sheet is supported on a depositing plate which is provided with fingers and of which the leading end is connected to the chains so that the plate is swung through 180.degree. at the delivery end of the chain conveyor and the sheet is placed onto a stack which, when finished, is discharged on spaced belts of a discharge conveyor under the chain conveyor. Each sheet is received in a stacking shaft defined by side walls, a vertically slotted rear wall and a base formed by prongs passing through the slots. The prongs are lowered as the stack height increases until they have passed between the belts of the discharge conveyor, whereupon they are withdrawn. End portions of each sheet projecting beyond the side walls of the shaft are turned inwardly over the fingers of the depositing plate by reciprocatable folding blades.

Abstract: In an apparatus for stacking sections separated from an intermittently fed web of sheet material, successive sections are held by clamping means and transferred to the upper arm of a first suction belt conveyor having suction holes which are at a spacing larger than the length of each section and attract the trailing end thereof. A second suction belt conveyor with suction holes at the same spacing overlaps the first conveyor and takes over the sections with its lower run by attracting the leading ends. An intermittently operatively stacking conveyor under the second belt conveyor has the sections deposited thereon by means for withdrawing the sections from the second belt conveyor.

Abstract: In a bag-making machine comprising a tube-making device and a device parallel thereto for forming bases on flattened individual tube sections fed longitudinally from the tube-making device, an apparatus for deflecting the tube sections comprises spaced parallel double belt conveyors respectively leading to and from a transverse double belt conveyor. A first turning device transfers the tube sections from one of the parallel conveyors to the transverse conveyor so that they continue to be fed longitudinally and a second turning device ensures that the tube sections are fed transversely to the base-forming device.

Abstract: An apparatus for opening and folding the end of a flattened tubular sheet to define the rectangular base of a bag or sack to be made from the sheet comprises a table having a slot through which the flattened sheet projects, the projection being formed into a bag base by suckers locating the projection in a pre-opened condition and grippers which engage opposed margins of the projection, one of the grippers being fixed and the other being secured to a pivotable arm.

Abstract: Apparatus for successively depositing sections severed from the leading end of a web of film on a support to form a stack in which the sections are staggered comprises an output shaft carrying two suction tubes or suction tube rows which engage a respective section and transfer it to the support as the output shaft is turned intermittently by interconnected crank arms from an input shaft which is horizontally offset from the output shaft and parallel thereto. The tubes or rows of tubes include an obtuse angle and are alternately revolved by the output shaft through the obtuse angle and the explement thereof.

Abstract: A continuous web unwinder comprising at least one operative station for an operative reel of web that is being unwound and one reserve station for a full reel comprises a direction-changing roller for the web unwound from the operative reel that, on depletion of the operative reel, is displaceable to the reserve station where it defines a nip together with a circulating belt for introducing an adhesive-coated leading end from the full reel.

Abstract: Parallel, spaced apart backing rods are carried by a rotating cylinder and serve the continuously supplied web. Back-pressure bars are extensible to engage and cooperate with welding bars. The backing rods and back-pressure bars are movable from and toward each other and provided with means for guiding a web with low friction. Those welding bars which are disposed near that sector of the cylinder in which the backing rods are disposed when they are retracted are moved concentrically to and at the same angular velocity as the back-pressure bars outside that surface of the cylinder over which the back-pressure bars are disposed. The back-pressure bars consist of rotatably mounted rolls, which are provided with a covering of elastic material which resists the welding heat. The welding bars have knife edge-like welding edges facing the rolls.

Abstract: Apparatus for depositing successive sections, such as carrier bag blanks, severed from the leading end of a web of superposed film layers fed through a transverse welding and severing station comprises nozzles for holding said leading end taut by means of an air jet, revolving suckers for engaging said leading end, and holding means to which said leading end is transferred by the suckers after each section has been severed.

Abstract: In bag-making apparatus, superposed plastics film layers of a travelling web are welded transversely along a processing path by pairs of welding jaws carried by chains to form bags which are severed from the web. At the end of or beyond the processing path, holding bars carried by the chains or by further chains parallel thereto engage the bags upstream of the weld seams and transfer them to take-off devices for stacking purposes.

Abstract: Sections intermittently severed from a web and conveyed by spaced parallel suction belts of a conveyor are applied to successive workpieces by a transfer mechanism comprising parallel suction bars insertable between and beyond the suction belts.

Abstract: Sections of bag-making material are successively and intermittently fed by double belt conveyors to arrive beneath a vertically reciprocatable push member which engages each section by suction and forms a central loop in each section while its ends are yieldingly engaged by brake shoes co-operating with side supports.

Abstract: A web of material is intermittently fed by feed rollers between and beyond pairs of clamping jaws comprising separated segments defining a gap receiving a reciprocatable severing knife. Beyond the clamping jaws, suction means hold the leading web end and, after said end has been severed, can be swung onto a support for a workpiece to which the severed web section is to be applied.

Abstract: Carrier bags resembling tank tops or singlets with cut-outs at the top for defining the handles are made by intermittently feeding a flattened tubular plastics web to a welding station where transverse weld seams are applied and bag sections are successively severed from the leading web end while the web is clamped between jaws. Each bag section is received by a suction belt conveyor with the assistance of a pressure roller and is then transferred to a suction drum which co-operates with a cutting cylinder for forming the cut-out and is provided with a projectable and retractable blade for folding the bag section transversely.

Abstract: Overlapping sheet articles on a first suction conveyor are intermittently diverted in groups by a lowerable second suction conveyor having a direction-changing roller which can be intermittently applied to the first conveyor and moved along therewith at the same speed and then returned.

Abstract: In a method of making bags from a travelling web of superimposed plastics film, the web is cut transversely, the edges of the ends so formed are moved apart and the ends are then transversely welded.

Abstract: In the production of transverse weld seams at intervals along a web of travelling superposed plastics films, the problem of weaknesses caused by shrinkage of each seam as it cools is solved by forming a loop in the web adjacent the intended seam and slackly clamping the web on each side of the loop before the seam is applied and the web released again.