公开(公告)号：US3566356A

公开(公告)日：1971-02-23

申请号：US3566356D

申请日：1968-02-29

申请人： MINNESOTA MINING & MFG

发明人： HOLM JOHN D ,  VOGELGESANG PETER J

IPC分类号： G11B5/706 ,  C09D5/23 ,  C09D7/12 ,  G06K19/10 ,  G06K19/12 ,  G07F7/08 ,  G11B5/70 ,  G11B5/80 ,  G11B5/62

CPC分类号： G11B5/7006 ,  G06K19/12 ,  G07F7/086

摘要： A DOCUMENT SUCH AS A CREDIT CARD OR TRNSPORTATION TICKET HAS A SUBSURFCE MAGNETIC RECORDING MEDIUM FOR ELECTRONIC PROCESSING OF INFORMATION ASSOCIATED WITH USE OF THE DOCUMENT. THE RECORDING MEDIUM EITHER BY ITSELF OR IN A COMPOSITE WITH OTHER MAGNETIZABLE MATERIAL IN THE DOCUMENT HAS AN A.C. DEMAGNETIZATION CURVE OF GRADUAL SLOPE WHICH LENDS ITSELF TO A UNIQUE AND ECONOMICAL TEST FOR VALIDITY AS A SAFEGUARD AGAINST COUNTERFEITING. THE GRADUAL DEMAGNETIZATION CURVE IS CONVENIENTLY ACHIEVED THROUGH THE USE OF MAGNETIZABLE PARTICLES OF TWO DISTINCTLY DIFFERENT COERCIVITIES.

公开(公告)号：US3668699A

公开(公告)日：1972-06-06

申请号：US3668699D

申请日：1970-11-12

申请人： MINNESOTA MINING & MFG

发明人： VOGELGESANG PETER J ,  HOLM JOHN D

IPC分类号： G06K7/08 ,  G08B5/24 ,  G08B5/26

CPC分类号： G06K7/087

摘要： A device for providing a visual indication of data represented by magnetic polarity alignments at each of a plurality of disparate magnetized regions defining a fixed two-dimensional pattern. The device comprises a board containing a plurality of disks positioned in said fixed pattern, which disks are constrained to rotate with their flat surfaces in the plane of the fixed pattern. Each disk comprises magnetized magnetic material having a magnetic polarity alignment parallel to a given flat surface of the disk and a plurality of visible indicia positioned on the given flat surface of the disk in a predetermined order in relation to the polarity alignment. A mask is positioned on the board to cover the disks and contains apertures aligned over a predetermined portion of each disk position for providing a view of whichever ones of the visible indicia on the disks are rotatably aligned with the apertures.

摘要翻译： 一种用于在限定固定二维图案的多个不同的磁化区域中的每一个处提供由磁极性对准表示的数据的视觉指示的装置。 该装置包括一个板，该板包含位于所述固定图案中的多个盘，该盘被限制为在其固定图案的平面中的平坦表面旋转。 每个盘包括具有平行于盘的给定平坦表面的磁极性对准的磁化磁性材料和相对于极性对准以预定顺序定位在盘的给定平坦表面上的多个可见标记。 掩模位于板上以覆盖盘，并且包含在每个盘位置的预定部分上对准的孔，用于提供盘上的可见标记中的哪一个与孔可旋转对准的视图。