Abstract: A plastics sack made from tubular material has one end of the tube folded to form a base defined by two triangular tucks interconnected by a welded-on or heat sealed joining strip, and two side flaps which incorporate the ends of the joining strip. A cover sheet is adhered over part of the corner tucks and over only one of the side flaps. The other side flap can be pulled out from beneath the cover sheet to form a controlled outlet for the sack contents or is temporarily secured to the outside of the cover sheet so that it can be readily detached for the same purpose.

Abstract: In a bag-making machine, a flattened tubular plastics web is intermittently fed by rollers and the leading end is held taut by air jets from tubes above and below the web. Welding jaws apply base seams for bag sections successively severed from the leading web end by knives. Between the knives and a stacking conveyor for the bag sections there is a supporting plate for the bag sections co-operating with a depressor. Two rows of needles pass alternately through slots in the supporting plate into a raised spiking position. Upon completion of a stack, the needles of one row are moved by a carrier to push the stack closer to the conveyor while the latter is moving and are eventually retracted from the stack while the needles of the other row take their place by moving into the spiking position for the next stack of bag sections.

Abstract: Lifting gear for a filled sack comprises a pair of clamping bars between which the gathered and flattened mouth portion of the sack can be clamped after the mouth portion has been slung thereabout. The bars are in the form of parallel cantilever arms and rotatable about an axis parallel thereto, one of the bars also being displaceable to and from the other bar while remaining parallel thereto.

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: In lifting gear for filled sacks, a device for engaging a gathered and flattened end of the sack adjacent the mouth thereof comprises two pairs of tongs. A first clamping bar is disposed at the free end of one limb of each pair of tongs and a second clamping bar, parallel to the first, is secured to two links which are pivoted to the free ends of the other limbs. The gathered and flattened end of the sack is introduced between the clamping bars as the open tongs are lowered, whereupon the links are revolved and the tongs are closed so that the end of the sack is slung about the clamping bars.

Abstract: A sack made from a tube of plastics material has its bottom constructed by folding an end portion of the tube so as to form two coplanar substantially isosceles triangular flattened portions with spaced confronting bases defined by plain edges and sides defined by fold lines. The space between the bases is bridged by a strip of material that overlaps the bases of the triangles and also projects beyond the base angles of the triangles. The projecting ends of the strip are folded over and the strip is welded to the sack bottom by seams which intersect at the fold lines.

Abstract: A lifting device for filled sacks comprises a frame in which a pair of parallel clamping bars are mounted to be revolved in unison by a crank about a common horizontal axis parallel to and spaced from the longitudinal axes of the bars. One of the bars is individually rotatable about its own longitudinal axis and is displaceable towards and away from the other bar. The gathered top of a sack is introduced between the bars when these are separated and automatically becomes wrapped around the bars and clamped therebetween as the crank is turned, whereafter the sack can be lifted by raising the frame.

Abstract: A supporting frame for suspending a filled sack from the hook of a crane comprises a rod of substantially triangular shape. The end of the sack adjacent the mouth is gathered, flattened and folded onto itself to define two sack layers. Both layers are laid over a first limb of the triangle that is opposite the apex and a clamping bar having a flanged end is inserted between the sack layers adjacent the fold line with the flanged end resting against a second limb of the triangle.

Abstract: In welding apparatus for two layers of travelling plastics film, a plurality of welding tools is moved in pairs along an elongated welding station through which the film layers are passed. The welding tools located on both sides of the layers co-operate with one another and are mounted in tool holders carried by endless chains. The tool holders on one side of the film layers are constructed so that they can be temporarily uncoupled from the associated chain and instead coupled to the respective tool holders on the other side of the layers.

Abstract: Sacks are successively filled and closed in an automatic process by suspending each sack from near the mouth and spreading the side walls apart, filling the sack, allowing it to settle on a support while keeping the side walls taut, bringing the side walls together near the mouth and folding them over onto themselves, welding a closure tape over the folded-over portion and the adjoining unfolded portion of the sack, crimping the unfilled upper part of the sack and gathering it to form a frill, and applying a clamping ring beneath the frill.

Abstract: In an apparatus for separating flattened valved sacks which are reeled in an overlapping formation, the reel is turned by endless belts pressing on the reel periphery as the overlapping sacks are being taken off the reel. A roller presses the overlapping sack formation onto the belts and this roller is disposed at a spacing of no more than about one sack length from the point where the sacks leave the reel.

Abstract: In an apparatus for making bags from a continuously fed flattened thermoplastic tubular or semi-tubular web of film, severing means for cutting the web into sections co-operate with a first welding cylinder for performing a welding operation on each section with the aid of welding tongs, the web sections being held to the welding cylinder by means of belts which partially envelop the cylinder, and a second welding cylinder is provided downstream of the first cylinder, the web sections being transferred to the second cylinder for the purpose of having a further welding operation performed on them.

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: Bags are fabricated from tubular plastics film as they are being filled. A flattened severed tube section of the bag material is clamped across its entire width at the bottom but only near the folded longitudinal edges (or the side pleats if such are provided) at the top. The walls of the tube section are pulled apart at the top between the clamped regions to present a filling aperture and welded together at the bottom across the entire width below the clamped region. After the contents of the bag have been inserted through the filling aperture, the top of the tube section is welded shut above the clamped regions and the bag is discharged.

Abstract: In an apparatus for separating valved sacks which are, with the aid of holding bands, coiled in an overlapping formation as a reel and for feeding the separated sacks to a filling machine, a stand for rotatably mounting the reel is provided with a frame carrying a guide roller at each end. An endless driven belt passed over the guide rollers presses against the reel periphery to turn the reel and unwind the overlapping sacks and their holding bands. The holding bands are coiled on spools of the frame while the overlapping sacks are fed to a conveyor which moves faster than the endless belt so as to separate the successive sacks from the overlapping formation.

Abstract: In a composite bag consisting of a paper or plastics outer envelope of one or more plies and a plastics inner envelope, the latter is closed at the base by a weld seam, the inner envelope material being incorporated in a welded or stitched base closure seam for the outer envelope. A line of weakness in the inner envelope material is disposed between the weld seam of the inner envelope and the base closure seam of the outer envelope.

Abstract: An apparatus for storing flat articles comprises a first conveyor, two deflectors for diverting the articles fro the first conveyor to a second slower conveyor disposed beneath each deflector at right-angles to the first conveyor for receiving the articles in an overlapping formation, a frame adjoining the second conveyor and carrying rollers at each end, endless driven conveyor belts passing over the rollers, the frame being pivotable about the axis of one of the rollers so that the other roller is disposed adjacent to a winding for receiving covolutions of the overlapping formation of articles and so that the belts are in contact with the convolutions to turn the core, and a supply reel of holding tape associated with each winding core.

Abstract: Apparatus for pivoting a tensioned web of material away from an adhesive applicator roller therefor comprises a guide roller for the web carried by first pivotal levers and a web tensioning bar extending parallel to the guide roller and carried by second pivotal levers so as to keep the web under tension when the first pivotal levers are swung to move the web past over the guide roller away from the applicator roller. Means are provided which are operative on pivoting of the first levers and which utilize the pivoting motion thereof for controlling pivoting movement of said second levers required to maintain or increase the tension in the web.

Abstract: Apparatus for reversing the running direction of a tube section in a machine for making sacks or bags comprises a turning cylinder with grippers for engaging the tube sections and pairs of rollers for conveying the tube sections in the opposite direction. At least one roller of the pair is movable and provided with a control effective to bring the rollers together with a snap action and separating them again after the tube sections have been transferred to a feed conveyor.

Abstract: Thermoplastic adhesive which has a tendency to form threads is applied to an article and, after terminating the supply of adhesive, the dispensed but not yet applied portion of adhesive is wiped on part of the article that is as yet free from adhesive. Apparatus for performing this method comprises a rotary cam for projecting an adhesive-applying nozzle towards successive articles moved past the nozzle and then retracting it again. The rotary cam has a first cam track portion governing retraction of the nozzle, a second cam track portion governing projection of the nozzle and an intermediate cam track portion for projecting the nozzle still further, control means being provided for opening valve means when the nozzle is in the projected position governed by said second cam track portion and closing the valve means during said still further projection of the nozzle.