Abstract: A strapping machine and method for applying flexible heat-sealable straps around objects includes a programmable control system that receives encoder and other signals from various sensors in the machine to regulate each strapping cycle. A feed/tension unit provides primary tensioning of the strap about the object based on signals from the control system. A motor driven roller and a pinch roller in the feed/tension unit each providing separate encoder signals to the control system to assist the control system in advancing and retracting the strap during feed and tensioning sequences, respectively, and provide signals indicating an exact position of the strap. A secondary tension system provides a final high tensioning force on the strap. The control system can automatically adjust individual strapping cycles, including tensioning, to compensate for various size bundles and different types of objects. Thereafter, a sealing head heat seals the strap and severs the sealed strap from the remaining strap coil.

Abstract: A strapping machine and method for applying flexible heat-sealable straps around objects includes a programmable control system that receives encoder and other signals from various sensors in the machine to regulate each strapping cycle. A feed/tension unit provides primary tensioning of the strap about the object based on signals from the control system. A motor driven roller and a pinch roller in the feed/tension unit each providing separate encoder signals to the control system to assist the control system in advancing and retracting the strap during feed and tensioning sequences, respectively, and provide signals indicating an exact position of the strap. A secondary tension system provides a final high tensioning force on the strap. The control system can automatically adjust individual strapping cycles, including tensioning, to compensate for various size bundles and different types of objects. Thereafter, a sealing head heat seals the strap, and severs the sealed strap from the remaining strap coil.

Abstract: A strapping machine particularly adapted for strapping unstable stacks of magazines and the like includes a means for positive pushing of the unstable stack into position at the strapping station by sliding the stack over a surface having a low coefficient of friction. At the strapping station, a compactor compresses the stack and a strap is automatically applied around the stack. Then, a pusher bar moves to contact the rearward end of the stack and to remove the strapped stack from the strapping station. Bundle stops which are used to properly position the unstrapped stack in the strapping station are mechanically linked to the pusher bar to retract when the pusher bar is used to move the strapped bundle from the strapping station. These bundle stops automatically reposition themselves so that this machine is ready to receive another unstrapped stack.

Abstract: A rough and final pull back tension are applied by moving the strap laterally of its path between a fixed strap end and a releasably anchored strap supply end, with the releasably anchored end being held by spaced pins biased together to obtain the rough tension and a greater final tension.

Abstract: An object is deposited at a strapping station on a high-speed, rapidly accelerating conveyor having a high-friction conveying surface. The object is raised off the high-friction surface by spaced tables having low-friction surfaces. Spaced, vertically downwardly extending bars engage opposite halves of opposite sides of the object and simultaneously move those halves transversely so as to rotate the object ninety degrees on the low-friction tables. A first strap is placed around the object before it is rotated; a second strap is placed around the object after it is rotated ninety degrees; then the conveyor accelerates the cross-strapped object rapidly out of the strapping station.

Abstract: A hold-down beam is provided on a rapid acceleration conveyor to hold articles, such as an unstable stack of newspapers, tightly against the conveyor for providing frictional engagement between the stack and the conveyor and move the upper part of the stack with the conveyor so that the stack will not topple. The hold-down bar is unpowered, that is, it is mounted for reciprocation in low-friction bearings so that its own frictional engagement with the top of the stack carries it along with the top of the stack until the stack is brought up to the desired velocity. A unique cable system for lowering both ends of a hold-down bar synchronously through an infinite number of positions and does not interfere with operation of a strapping machine.

Abstract: A hold-down beam is provided on a rapid acceleration conveyor to hold articles, such as an unstable stack of newspapers, tightly against the conveyor for providing frictional engagement between the stack and the conveyor and allow the upper part of the stack to move with the conveyor so that the stack will not topple. Compression blocks are provided at adjustably spaced locations on the bar for pressing bowed stacks.

Abstract: A strapping machine and method for applying flexible, heat sealable straps around objects in which the supply coil of strap and the feed rollers for a strap accumulating compartment are driven by a common rotatable drive for synchronous feeding. A strap feeding unit for feeding flexible strap in which a feed and pinch roller extend through opposed slots which intersect a strap carrying groove which totally confines the strap.A strap tensioning mechanism in which rough tensioning and final tensioning are achieved by the movement of a single mechanical plate. A cutting and sealing head in which feeding of a new strap around the object can occur simultaneously with the sealing of the previous strap. A track opening mechanism which is operated by components of the sealing and cutting head.

Abstract: A parallelogram linkage controls the speed of a sealing and cutting bar while in engagement with a polyethylene wrap while the wrap is being sealed around an object moving along a conveyor. The linkage assures synchronism between the speeds of the sealing and cutting bar and a resilient roller between which the wrap is pressed during sealing and cutting. Pressure on the sealing and cutting bar is controlled by an adjustable but controllable air pressure link. Sealable wrap is uniquely stored on the top and bottom sides of the conveyor such that it may be freely released when the object engages a web formed by the initial sealing of the two wraps together at a wrapping station. Once the wraps have been cut and sealed to form a new web at the rear of the previously wrapped object, the web is drawn back to position it for engagement by the next object in the path.