Abstract: The invention concerns a device with a mobile part comprising two crowns (1 and 13) rigidly coupled with rods passing through the hub (7) outside the bearings (6). The springs (20) press that frame against the fixed ring (10) such that the pins (21) are engaged in the holes (22). The lever (15) is provided with cam-branches (18) supported by the ring (23). When the lever (15) pivots about the spindles (19) the wheel is blocked or released.

Abstract: A band or strap of thermoplastic material which has been placed around a package or article being wrapped is put under tension by means of a tensioning device. The connection apparatus for connecting overlapping ends of the thermoplastic band material is placed within the area of the band or strap under tension and is used to connect these overlapping ends together. The connection apparatus welds the overlapping ends of the strap together using friction by rubbing the lowermost end in a transverse direction with repsect to the longitudinal axis of the band or strap against the uppermost strap end by means of a vibrating or oscillating welding jaw. The welding jaw is driven by an internal battery-powered DC-motor. The connection apparatus is especially well suited for use with a separate tensioning device and can be used in lieu of previously used seal clamps or pliers, independent from a connection with an electric power network or a source of compressed air.