| 摘要 |
<p>A sheet feeder comprising a platform (42) for stacking sheets (S) and feed head assembly (100) at the front of the platform (42) for acquiring individual sheets (S') from the stack and feeding separate sheets (S') into a sheet handling machine. The feed head assembly (100) is comprised of a vacuum plenum (102) having a port plate (101a), across which a perforated belt(s) (104) moves in a closed loop. The port plate (101a) includes ports (105,106) wherein the air flow through some of the ports (105) is restricted by an intermediate plate (110) positioned within the plenum (102) which, in turn, has a restrictive passage (111) therein through which air from the restricted ports (105) must flow into the plenum (102). <IMAGE></p> |
