| 摘要 |
A device for registering a sheet with a side stop at either one of the opposite lateral edges of a feed table in a printing press. The device includes a housing having a top surface which is flush with the feed table. A suction head is flushly recessed in the surface of the housing and mounted in a slide in the housing for limited reciprocating movement. The housing is shiftable between alternative working positions at the respective lateral edges of the feed table. For driving the suction head timed with the arrival of a sheet, a drive shaft is provided in the housing having a pair of face type cams spaced axially from one another cooperating with a cam follower which is secured to the suction head in a position between the cams. Springs are provided for biasing the suction head in opposite directions. A shiftable yoke selectively engages the springs with the suction head so that the cam follower engages a selected one of the cams. A rotary value on the drive shaft applies suction to the head timed with the movement of the head toward the adjacent side stop. The cams are in mirror image, that is, 180 DEG out of phase, so that the sheet moves into contact with one of the side guides, with application of suction, timed with the feeding of the sheet on the feed table regardless of which side stop is being employed. In a modified form of the invention application of suction to the sheet is followed by a puff of compressed air. |
