Appeal No. 2002-1053 Page 9
Application No. 09/702,981
contact or engagement with the power rollers 118 and 120. This is assured because a
biasing spring 154 wraps around a pulley 156 which is secured to the shaft 138 and
biases the shaft in a clockwise direction, as viewed in Figure 2.
Because the gears 80 and 82 are pulling initially from the slightly sagging (or
even free-hanging loop 126), there is little drag on the sheet material and little chance
that the gears will tear the sheet material as they start to rotate or will cause tearing
upstream of the gears. As the sheet material advances, the loop 126 is taken up
against the dancer arms 148 and 150. As this continues, the dancer arms 148 and 150
are forced to rotate from the position shown in Figure 4 toward the position shown in
Figure 5. This counterclockwise rotation causes the pressure rollers 134 and 136 to
squeeze the sheet material against the power rollers 118 and 120 whereupon the
power roller drivingly engage the sheet material and pull it from the sheet roll. Because
power rollers 118 and 120 are driven with a surface speed that is greater than the
speed at which the feeding/connecting assembly 84 draws material through the forming
assembly 14, if the pressure rollers 134 and 136 press the sheet material against the
power rollers 118 and 120 firmly enough that there is no slippage between the material
and the power rollers, the loop 126 will grow in size. However, as the loop grows in
size, the pinch force acting on the sheet material will be reduced and slippage
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