Illinois Tool Works Inc.

Strapex Ag

Strapex Holding Ag

Charles Fischer

An unwinding apparatus ( ) for a strapping machine ( ) for the purpose of unwinding a band ( ) from a band-supply reel ( ) comprises at least two bearing rollers ( ) which are located one behind the other in the circumferential direction of the band-supply reel ( ) and on which the band-supply reel ( ) rests by way of its respective outer band circumference, it being possible for at least the downstream bearing roller ( ) to be driven for the purpose of driving the band-supply reel ( ).

Unwinding apparatus

A tensioning unit for a strapping machine serves for tensioning and sealing a band guided around an item to be strapped. It has a tensioning head and housing. The tensioning head includes a tensioning device and clamping and sealing subassembly. Toward the end of a tensioning operation, the head can be displaced relative to the housing in a band-running direction, counter to tensioning direction. Also provided in the housing is a band guide arranged downstream of the clamping and sealing member, in the band-running direction, subdivided into front and rear band-guide parts. In this case, only the front band-guide part can be displaced, together with the tensioning head, relative to the housing, whereas the rear band-guide is moved transversely to the band-running direction by the front band-guide part, which is moved in the band-running direction B, counter to a spring force.

Tensioning unit

A deflecting subassembly for the guided deflection of a band consisting, in particular, of plastic may be provided, in particular, for a strapping machine comprising a strapping subassembly , for the purpose of deflecting the band in a region located between a band store and the strapping subassembly . The deflecting subassembly comprises a deflecting roller , a band-inlet channel , which is arranged upstream of the deflecting roller , a band-outlet channel , which is arranged downstream of the deflecting roller , it being possible for the band-inlet channel and the band-outlet channel to be adjusted relative to one another, and an outer, flexible directing member which bridges the interspace between the band-inlet and band-outlet channels and , respectively, and is located opposite the outer circumference of the inner deflecting roller

Deflecting subassembly

A tensioning device for tensioning the plastic band. The device has a tensioning element which can be rotated about an axis and has a flat gripping region. A clamping element is also mounted such that it can be rotated about the axis and, when the tensioning element is in the inoperative position, is supported against a stop. In this position, the plastic band can be moved freely between the gripping surface of the clamping element and the tensioning element. To tension the plastic band, the tensioning element is rotated in the tensioning direction and the gripping region of the tensioning element is thereby moved against the gripping surface so that the plastic band is held in a planar manner. With the plastic band being held, the gripping region, as seen in the tensioning direction and with respect to the axis, is inclined inwardly in the radial direction. During further rotation of the tensioning element the plastic band which is clamped between the tensioning element and the clamping element is tensioned.

Band tensioning device on a strapping machine

A continuously driven endless belt trains about deflection rolls within a frame which surrounds a tunnel for the reception of the package which is to be strapped or tied with a ligature in the form of a plastic strap or band. Connectable with the revolting belt is a carriage which guides the plastic strap or band withdrawn from a supply roll along a prescribed path of travel about the tunnel. After each revolving motion of the plastic strapping band the carriage is again uncoupled from the endless belt at the region of a strap wrapping and connection unit, in order to transfer the starting portion of the strapping band which has been guided around the package to a strap or band closure device and, following the tensioning and cutting of such band, to engage a new starting band portion to accomplish the next strapping of the band about a new package. With such construction of the package strapping machine it is only necessary to again accelerate and brake the carriage which possesses low mass during each operating cycle of the machine, so that there is no need for any control device for the belt drive and there is possible an extremely high acceleration of the carriage for carrying the strapping band about the package.

Growing community of inventors

Wohlen, Switzerland

Charles Fischer