| 摘要 |
679,423. Statistical apparatus. INTERNATIONAL BUSINESS MACHINES CORPORATION. Sept. 18, 1950 [Nov. 23, 1949], No. 22852/50. Class 106 (i). A statistical machine record card which may be formed in a continuous strip and detached as required, is perforated so as to present a clear straight edge when separated on both sides of the weakened division. The record card 1 is then weakened along two parallel lines 3 closely spaced apart by perforating slits intermittently along each line in staggered relationship, so that the slits of one line are adjacent to the spaces between slits of the other as shown in Fig. 1. When one record card is detached from the next, tearing occurs only at 5 in Fig. 3, leaving straight edges 3 which are suitable for handling in card - controlled accounting machinery. |
