| 摘要 |
1,142,883. Sensing record cards. INTERNATIONAL COMPUTERS Ltd. 13 June, 1967 [8 July, 1966], No. 30677/66. Heading G4M. Perforations in a card 1 are sensed by means of fluid flowing from channel 5 to open-ended channel 9, a member being responsive to changes in pressure in the channel to produce an electrical signal. In Fig. 1 a diaphragm 12 stresses a piezoelectric element 14 by way of link 13. In Fig. 2 (not shown), fluid is supplied to the underside of the card by way of an open-ended chamber and a piezoelectric element is resiliently clamped across the mouth of this chamber. In Fig. 3 (not shown) fluid is supplied intermediate the open ends of a chamber and normally escapes across the card path from one end of the chamber, but when this end of the chamber is blocked by a non-perforated region of the card, the fluid escapes from the other end of the chamber and stresses a piezoelectric element clamped across this end of the chamber. |
