Abstract: Packaging such as a blockbase sack (201) suitable for packing of particulate material has an inner bag having two layers of polyethylene, surrounded by an outer bag (201) having three layers of polyethylene. Each bag has a closed bottom and has an open top (208) prior to filling. After filling of the inner bag, the inner bag is closed by a first heat seal along zone (205) in a heat-sealing operation, which can be performed through the outer bag (201) in such a way that the outer bag (201) is not heat sealed to the inner bag at that point. The outer bag (201) is closed by a second seal (207) located between the first seal (205) and the top of the bag (208). A frangible zone (206) is located between the first (205) and second (207) heat seals to enable the outer bag (201) to be removed from the sealed inner bag by cutting or tearing along the frangible zone (206).

Abstract: A device for eliminating defective flat objects, which are being conveyed individually and at a distance from each other, preferably tubular segments or sack workpieces during the production of sacks, and for forming stacks of flawless objects, said device comprising a twin belt conveyor, which conveys the objects and comprises groups of continuous belts that are spaced apart and cycle parallel to each other; comprising a system for scanning the objects; and comprising a shunt, which eliminates the objects that are recognized to be defective. Behind the discharge end of the twin belt conveyor there is a stack shaft with an intermediate stacker plate, and before the discharge end there is a rake-shaped deflecting element, which forms the shunt and can be moved between the bottom conveying run of the twin belt conveyor and which guides the objects, recognized to be defective, into a place of deposit, arranged above the stack shaft.

Abstract: A device for welding flatly stacked workpieces, preferably layers of tubular segments in the manufacture of sacks, by means of welds of predetermined contour in the ultrasonic welding process comprises at least one sonotrode, which is adjustable, but is stationary during the welding operation and at least one contour roller, which is assigned to said sonotrode and whose shell is provided with a contour profile, which matches the contour of the welds to be formed and which rotates at a circumferential speed that corresponds to the speed of the workpieces passing through. To weld together quite well flatly stacked workpieces, even when they tend to unfold or spread apart, the sonotrode is enclosed by a continuous belt or strap, revolving over deflecting and drive rollers. The carrying run of the belt, passing the active surface of the sonotrode, forces the workpieces to be welded against the contour roller.

Abstract: To palletize stacks of flat objects, preferably stacks of sacks or bags, the stacks are deposited in several layers one on top of the other on a pallet in such a manner that the stacks of each layer overlap at least two stacks of the layer lying underneath. To palletize stacks of flat objects with higher productivity, large packages, which comprise partially overlapping stacks, are made from at least two stacks before the stacks are deposited.

Abstract: An apparatus for manufacturing cross bottom sacks from laid-flat tubular sections consists of a frame having:- a table, means for holding the tubular section thereon in a processing station where the ends of the tubular section become opened out into a bottom square or rectangle, a suction gap arranged in the table in the zone of one of the ends of the tubular section, and suction means mounted in the frame above the suction gap and which is able to be raised and lowered for opening one end of the tubular section. Above the plane of the tubular section situated in the processing station, a slide can be extended and retracted over the table in the direction of the median line of the tubular section, the median line of the slide defining with the median line of the tubular section a plane perpendicular to the plane of the tubular section. The width of the slide is less than the interspacing of the hypotenuses of the two opened-out corner folds from each other.

Abstract: An apparatus for the transfer of flat workpieces from a first conveyor to a second conveyor consists of a first conveyor with two endless pulling members circulating parallel to each other over guide wheels or drive wheels which carry in pairs supporting elements with pins. The pins perforating and conveying the workpieces project above a table forming the conveyance path by virtue of the supporting elements and the pins having attachments which run in guides that are parallel to the table and which displace the attachments towards each other. The pulling members of the second conveyor carry in pairs supporting elements with pins which project above a table forming the conveyance path. In the transfer zone of the two conveyors, a plunger is arranged in the frame and mounted in guides. The plunger can be raised and lowered and impales the workpieces onto the pins of the second conveyor.

Abstract: A device for decollating stacks of flat objects includes a stack magazine. The base of the stack magazine supports the stack and includes revolving rollers that form a continuously moving series of rollers, pass underneath the stack magazine, and roll along the lowest object of the stack. A conveyor system is arranged underneath the upper run of the series of rollers and extends at an angle to the series of rollers. The lowest object that is removed from the stack by one passing roller is deposited on the conveyor system. A suction device moves or suction devices move between the rollers in the cycle in which the rollers pass underneath the magazine. The suction device or devices pulls or pull down one lateral edge of the lowest object between two rollers. The leading roller still supports the stack via the object and the trailing roller passes between the object and the object situated above so as to cause a secure separation of the lowest object from the stack.

Abstract: For manufacturing cross bottom valve sacks, the ends of continuously transported tubular sections are opened out with the formation of so-called "bottom squares" with triangular corner folds lying opposite each other. A valve leaf or a valve tube is tacked onto one side of an opened-out bottom square in such a way that, after the side folds of the opened-out bottom have been folded-in with a mutual overlap, the leaf forms a valve tube leading into the inside of the sack, and with its outer end freely accessible at one side of the sack bottom. For checking the correct position of the valve leaves or of the valve tube, the valve leaf or the valve tube, or the zone of the corner fold, covered thereby when the leaf is tacked in its correct position, is provided with a mark that can be registered by a photocell device fixed to the frame. The photocell device is activated by a reference pulse when, in the manufacturing installation, the sack bottom has reached its predetermined position to be checked.

Abstract: An arrangement for separating flat stacked objects is composed of a stacking hopper, the base of which supports the stack and is composed of rolls. The rolls pass through at intervals and roll against the respective bottommost workpiece. The rolls are provided in a traveling series and are driven in a rotating manner. A conveyor belt for transporting material away is arranged below the series of rolls. The respective bottommost workpiece successively peeled off the stack by each roll passage is placed onto the conveyor belt. In sync with the passage of the rolls, suction boxes grip and pull down a lateral edge of the respective bottommost workpiece between two rolls in such a way that the roll that arrives below the stack still supports the stack through the workpiece. The subsequent roll passes between the workpiece and the workpiece located above the previous workpiece and causes a reliable separation of the respective bottommost piece from the stack.

Abstract: An apparatus for stacking double bags, which have been severed by hot-wire welding from a tubular web of plastic and have opening-defining edges adjacent to their center line, includes a wicketer having a horizontal shaft and pairs of juxtaposed spokelike radial feeding arms which are axially spaced apart and secured to the shaft and are provided with means for retaining the double bags. Stacking pallets provided with upstanding stacking pins are slidably movable between the feeding arms, by which the double bags are deposited on the pallets, e.g., on needles provided on the pallets.

Abstract: In a device for transversely welding and cutting tubular film into bags, feed rolls advance the film to a gripping rail which grips the leading end of the film during operation of cutting and welding devices located behind the gripping rail in the direction of feed. To ensure proper tensioning of the film, the feed rollers are reversed after the film is gripped and prior to operation of the cutting and welding devices.