| 摘要 |
<p>The system comprises a frame which carries an upper fixed clamp and a relatively movable lower clamp, the frame being movable relative to a work support surface. The two clamps are normally held apart (for loading), specifically by forces applied by an air cylinder. The frame is movable towards the work support surface under variable forces, specifically a low force applied by a second air cylinder to engage the lower clamp with fabric on the support surface, the second cylinder operating against the upper clamp. A higher force can then be applied by the second cylinder, to bring the two clamps together by overcoming the force of the first air cylinder which holds the clamps aprt.</p> |
