| 摘要 |
1,017,747. Magnetic disc records and apparatus. INTERNATIONAL BUSINESS MACHINES CORPORATION. Oct. 9, 1964 [Oct. 30, 1963], No. 41223/64. Heading G5R. A record for language laboratory use takes the form of an apertured membrane of magnetically-coated terephthalate plastics 1, radially tensioned during manufacture (Fig. 1, not shown), the tension being maintained by epoxy resin-attached rings 8, 9. The tension is adjusted such that when a spherical head-tip 12 of some 3-inch radius is applied, the material 1, Fig. 3C (not shown), flows around the tip in intimate transducing contact, without the formation of " bowwaves," which would otherwise cause wow and flutter. |
