| 摘要 |
1300519 Selective printing CREED & CO 14 Oct 1971 47836/71 Heading B6F Linewise movements of a typewheel 1 are achieved by a pinion 5 driven at constant speed from a shaft 3, the pinion being keyed to a helical groove 7 in a rod 6 which can be operated in three modes: for maintaining the typewheel in a required position the rod 6 is rotated at the same speed as and in the same sense as the pinion 5 through a clutch 9, for advancing the typewheel along a print line the rod 6 is rotated faster than and in the same sense as the pinion 5 through a clutch 8, and for returning the typewheel to the beginning of a print line the rod 6 is stopped by a brake 10. The typewheel may rotate about the rod 6 or about an axis perpendicular thereto by suitable coupling with pinion 5. |
