Abstract: An apparatus for sealing superposed film webs or flat lying tubular webs of a thermoplastic synthetic material, including sealing bars heatable by heating appliances, which are displaceable towards each other and away from each other and over whose front surfaces there can be spread a separating sheet of a material not sticking to the synthetic material.

Abstract: The invention relates to a method for making bags preferably provided with side folds or other flat workpieces, which have a slip extending beyond their boundary. In accordance with the invention partly prefabricated bags are laterally supplied to a conveyor belt driven in a timed manner, and are seized there by grippers and fixed. By means of a glue applicator a glue strip is applied to the bag in its bottom region during the timed feeding movement of the conveyor belt. Finally, in a slip application station a slip is supplied each laterally to the conveyor belt and is placed onto the glue surface. The invention furthermore relates to an apparatus for carrying out the aforementioned method.

Abstract: An apparatus to apply reinforcing slips provided with a glue coating to a web which has transverse perforation lines, comprising means for tearing from the web the sections which are joined at the transverse perforation lines.

Abstract: An apparatus for stacking flat workpieces, which are provided with stacking holes, on stacking pins or stacking fingers of an endless flexible conveying element or of an endless conveying chain, which revolves around reversing pulleys, which conveying element or conveying chain is advanced by one step whenever a stack consisting of a predetermined number of workpieces has been formed. The apparatus includes a feeder for feeding consecutive workpieces to be stacked and a rake for pushing the workpieces onto the stacking pits or stacking fingers. The stacking fingers are mounted on elongate pedestals, which are secured to the conveying element or conveying chain and have a width which is smaller and a length which is larger than the diameter of the stacking holes.

Abstract: In a process for producing flattened gusseted tubing from a flat continuous film of synthetic thermoplastic, gussets are formed in the flat continuous film in such a manner that lateral marginal portions of the film are superposed adjacent to the outer edge of a covering gusset. A portion of the covering gusset is then reversely folded on itself, the marginal portions are subsequently provided with a longitudinal seam weld in a region which was aligned with the outer edge of the covering gusset before the gusset portion was reversely folded, and the reversely folded portion is then unfolded.

Abstract: Apparatus for winding webs to form supply rolls under a substantially constant web tension comprises a winding shaft, which is rotatably mounted in a machine frame and driven by an electric motor, a rocker, which is pivoted to the machine frame and has mutually opposite, freely protruding arms, which are equal in length and at their ends carry freely rotatably mounted dancer rollers, and means for detecting a deflection of the rocker resulting in a displacement of said dancer rollers from a normal position, in which they are horizontally aligned. Two winding shafts are provided, the first of which is driven by a transmission from the electric motor and the second of which is driven via a differential, which has a first input member that is coupled to the first winding shaft, and via further power-transmitting means succeeding said differential.

Abstract: To make plastic carrying bags or sacks, sections are cut or are severed by hot wire welding from a gusseted tubular film by a formation of transverse seam welds and transverse severing cuts or by hot wire-welded transverse seam welds. At least in their bottom portion the sections are provided with corner seam welds, which are separately formed in the two folds and which diverge obliquely from the outer fold lines toward the top and/or bottom seam weld and terminate short of the inner fold line and merge into the latter. To prevent in the making of the carrying bags an elongation of the intermediate portion of the tubular film, the latter is initially formed with corner seam welds only in one fold of each of the two gussets before the transverse seam welds and transverse severing cuts or hot wire-welded transverse seam welds are formed. When said corner seam welds have cooled, congruent corner seam welds are formed in the respective other folds.

Abstract: An apparatus is disclosed which serves to move a carriage in one direction over a predetermined distance at a substantially uniform velocity and to return the carriage at a varying velocity so that a film web delivered at a constant velocity is intermittently advanced relative to a welding device fixed to a frame. The apparatus comprises a lever, which is adapted to be pivotally oscillated by a drive and which by virtue of a first guide provided on the lever and a slider or roller cooperating with the guide imparts a motion to the carriage. The carriage is movable on track rods in a plane which is parallel to the plane in which the lever is pivotally movable. In order to provide an apparatus which is compact and space-saving, the lever is driven by a crank, which revolves in a plane parallel to the plane in which the lever is pivotally movable.

Abstract: Apparatus for winding a web section without using a core, the web section including a plurality of transversely extending perforation lines and wherein a torn web section is removed from a continuously supplied web. The apparatus includes two winding stations that are diametrically opposed on opposite sides of rotatable, circular carrying discs. Each of the winding stations includes a pair of opposed winding heads, and the winding heads each includes a pair of winding pins that extend in the direction of the winding aixs. The pins are rotatably mounted for rotation as a pair about the winding axis and are connected to a rotary drive. The winding pins are also extendable to a winding position and are retractable to a non-winding position. When in the winding position the pins extend outwardly from the winding head and are spaced from each other a distance sufficient to receive a web therebetween, and upon rotation of the winding heads the web is wound into a roll without the need for a core.

Abstract: Apparatus for stacking and conveying flat articles that are preferably provided with locating holes and preferably consist of bags that have been severed from a tubular or semitubular plastic film web and have been closed by welding. The bags are carried from a forming station to a pair of adjacent, parallel stacking conveyors by a rotatable wicketer having spaced pairs of radial transfer arms. The stacking conveyors include endless belt like carries that pass around rotatable wheels or rollers and are intermittently driven. The carriers include upstanding stacking pins or stacking needles, which extend from and are secured to carrying plates mounted on the carriers. Two spaced, adjacent stacking conveyors are provided and different tools for acting on the intermittently conveyed stacks of bags are selectively provided and detachably secured to the frame of the apparatus between the stacking conveyors.

Abstract: In a stacking apparatus for sheets delivered by a double belt conveyor including spaced parallel conveyor belts, a stacking station beneath the discharge end of the conveyor is supplied with sheets by parallel suction arms which move at the conveying speed between the conveyor belts and therebeyond, are lowered to the stacking station to deposit a sheet while the suction effect is interrupted, and are then returned to the conveying plane.

Abstract: In an apparatus for making plastics carrier bags from a web of tubular film of thermoplastic material, a feeding mechanism intermittently conveys the webs by one bag width and a severing mechanism cuts the web into half tubes along an undulating curve. A carriage displaceable in the machine frame transversely to the feeding direction of the web is reciprocated by a drive derived from a first rotating control cam through gearing. A cutting knife pivotable in the carriage about its longitudinal axis passes through the plane of the tube about an axis perpendicular thereto and is so controlled by an oscillating drive derived from a second rotating control cam that its edge is substantially tangential to the undulating curve at the cutting point. A detour assembly retards one of the half tubes to bring the bag side edge zones into phase and each half tube is formed into bags by a transverse sever-sealing device.

Abstract: In an apparatus for applying handles to an intermittently fed web of plastics sheet material and severing bag sections therefrom by transverse weld seams, treating means for the web disposed upstream of two successive pairs of feed rollers and operative when the web is stationary simultaneously carry out like processes on a plurality of web sections which will later be severed into a corresponding number of bags. The feed roller pair nearest to the treating means is effective to feed the web in steps equal to the sum of the lengths of simultaneously treated web sections whereas the other pair feeds the web in steps equal to only one web section length but is operative as many times more frequently as there are simultaneously treated web sections.

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 welding apparatus for web material, one of a pair of feed rollers for the web is reciprocatable by a crank shaft. A swing arm oscillated by the crank shaft oscillates a gear segment for intermittently driving the feed rollers. A clutch and brake unit for uncoupling and braking the feed rollers and vice versa is operated by a cam rotating with the crank shaft. The crank shaft is operatively connected to a disc which is provided with an eccentric slide block and turns at the same speed as the crank shaft. The slide block is longitudinally displaceable in a slot of the swing arm. The driving motion for the feed rollers occurs during rotation of the slide block by way of the sector remote from the pivot shaft of the swing arm.

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: Two longitudinally split plastics tubes are fed in parallel by respective feeding means and each have at least one margin folded back to have handle-hole reinforcements applied to it at intervals. The reinforcements are severed from a web by a rotary knife. The handle holes are formed in the tubes by punches simultaneously with the operation of separating welding means for welding off carrier bags from both tubes. Two photocells upstream of the reinforcement applying station scan printed register marks on the tubes and bring the tubes into phase with the rotary knife by operating a respective motor-driven indexing roller for each tube. Two further photocells for scanning the register marks are adapted to stop the feeding means independently when the tubes are correctly positioned in relation to the punches and separating welding means.

Abstract: A stacking, severing and block-forming machine for sheet articles such as flattened plastics bags comprises a stacking station at which the articles are superposed against a displaceable abutment, a mechanism for compressing each stack, a conveyor mechanism for taking each stack to a severing and block-forming station when the abutment has been displaced and a heatable knife for cutting through the stack and simultaneously interconnecting the cut edges of the articles to form blocks. The compressing mechanism is at a stationary location downstream of the stacking station and the knife is displaceable in the upstream direction during cutting.

Abstract: An apparatus for making bags from a continuously fed heat-sealable web comprises supporting bars for the web arranged on a rotary cylinder parallel to and at a spacing from one another. Means for transversely welding and separating the web comprise welding bars co-operating with backing bars. The backing bars are arranged between the supporting bars and are displaceable towards the welding bars. The supporting and backing bars are movable towards and away from one another in a zig-zag line during transference of the web passed therebetween. The supporting bars for receiving and holding the web are axially extensible and retractable at least over the width of the web. In the region of the cylinder sector in which the supporting bars are retracted and the separating weld seams are produced, the welding bars are guided to be concentric with the cylindrical enveloping surface swept by the backing bars, namely outside said enveloping surface and at the same angular speed.

Abstract: A continuously travelling web of material is processed at longitudinal intervals between a pair of confronting transverse processing tools. The tools are mounted on carriers guided in pairs on endless chains to follow a path composed of two parallel straight sections joined at the ends by semi-circular sections, the latter being relatively adjustable. The chains are guided on adjustable sprockets so that their runs are parallel and overlap. Confronting extensions of interconnecting hinge pins for the links of the chains are engageable in recesses provided in the tool carriers.