| 摘要 |
<p>A drive mechanism for the bend arm of bending apparatus wherein a drive motor has the drive shaft thereof generally parallel to the axis of pivoting of the bend arm assembly, and along a line at an angle to the feed direction of a tube. The drive shaft is directly coupled to a bell crank having first and second generally perpendicular arms. A like bell crank arrangement is formed in the bend arm and is driveably coupled to the bend arm pivot shaft with the bend arm bell crank in aligned relation to the drive motor bell crank. First and second generally identical rigid noncompliant link arms have the first ends thereof pivotally coupled to the free ends of the arms of the bend arm bell crank, with the other end thereof pivotally coupled to the free ends of the drive motor bell crank. The link arms are generally L-shaped, with the distal ends of the short legs thereof coupled to the bend arm bell crank, one of the ends above the crank and one below the crank. The distal ends of the long arms are similarly interconnected with one above and one below the drive motor bell crank. The position of the drive shaft relative to the tube feed direction, coupled with the angular configuration and spatial positioning of the short leg relative to the long leg of the link member enables pivoting of the bend arm through an angle in excess of one hundred eighty degrees.</p> |
