Abstract: An apparatus is provided on a strapping machine frame adjacent a strap chute and adjacent a strap end gripping and sealing assembly and has a pivotably mounted strap guide arm and gripper for guiding the strap during feeding in a first, upper position and for gripping the strap when the arm moves downwardly away from the first position. A single, reversible, rotating drive motor is mounted for movement with the guide arm and powers a gear drive assembly which is engaged with the motor and movable therewith for (1) rotating feedwheels to feed the strap to form a loop when the motor is rotating in a first direction, (2) rotating the feedwheels to withdraw the strap to pretension the loop with a first predetermined tension when the motor is rotating in a second direction, and (3) rotating a high tension pinion gear when both (a) the motor is rotating in the second direction and (b) the tension in the strap exceeds the predetermined, first tension.

Abstract: A method and apparatus is disclosed for binding an article with strap. A strap is encircled about the article to form a loop with the leading end segment of the strap overlapping an adjacent segment of the strap. The leading end is gripped to prevent further feeding and to subsequently restrain it against movement relative to the article while the trailing portion of the strap is retracted to draw the loop tight around the article. While holding the leading end segment of the strap and an adjacent overlapped segment against relative movement and under tension, either (1) a joint is first formed in the overlapping segments and the tension is then gradually released in the trailing portion of the strap to avoid shock loading of the joint and the machine or (2) the tension is first released only in the trailing portion of strap and the joint is then formed with tension in at least the overlapped segment adjacent the strap free end.

Abstract: A combination jam-clearing and torque sensing traction wheel assembly and strap feed stopping mechanism is disclosed for use in a strapping machine which feeds strap in a chute about an article to form a loop and subsequently tensions the loop tightly about the article. The strap is fed into the chute by a rotating traction wheel which is driven through a torque sensing assembly comprising a driven plate, a spring-biased driver plate, and drive motor. Feeding of the strap is intermittently stopped and started as the driver plate is forced out of engagement with the driven plate when the torque increases beyond a predetermined amount in response to increased strap feed resistance resulting from an obstruction in the chute. In one embodiment, the strap feed stopping mechanism includes a permanent strap end abutment member located just past the strap overlap region in the strapping machine.