| 摘要 |
<p>1357480 Training and securing straps around packages SIGNODE CORP 11 May 1972 [11 June 1971] 22181/72 Heading B8C [Also in Division F2] In a strap feed and tensioning mechanism in which, having fed a plastics strap 10, the drive to two wheels 22, 24 is reversed to produce the required tension in the strap (which surrounds a package (16)), the strap is allowed to run spaced from the serrated periphery of the slower turning wheel 24, in the feeding direction, by contact with a member 30, and is prevented from slipping, during tensioning, by being pressed by the member against this periphery. On reversing the drive, the faster wheel 22 takes up the slack in the strap loop until a predetermined initial tension in the strap causes a slipping clutch to slip, whereafter wheels 22 and 24 rotate in synchronism to re-wind the strap. A solenoid 58 is actuated, in response either to the slowing of wheel 22 or to the slipping of the clutch, so as to tension member 30 against the periphery of wheel 24, as arm 38 is turned into the dotted line position. Rollers (42a) of member 30 have flanges (50) which, in the absence of a strap 10, contact ledges (50) and thus hold the bodies of the rollers clear of the serrated surface to prevent them from being damaged, in the event of an inadvertent energization of solenoid 58.</p> |
