| 摘要 |
The arrangement comprises a magnetic key (3) which has one behind another in its direction of insertion a plurality of permanently magnetic coding areas (17), which are arranged in an array having predetermined array spaces and which define a key code. The magnetic key (3) further has one behind another in the direction of insertion at the array spacing of the coding areas permanently magnetic clock-pulse areas (21), which are arranged with alternating direction of the magnetic field and define an item of clock-pulse information. A reading device scans the coding areas (17) and the clock-pulse areas (21) by means of magnetic-field sensors (19, 23) in a serial fashion. The clock-pulse areas (21) are mutually offset by half an array spacing in the direction (5) of insertion relative to the coding areas (17). The key code information is evaluated as a function of clock pulses which the reading device generates as a function of the minimum in the absolute value of the field strength between adjacent clock-pulse areas (21). Alternatively, the clock-pulse areas (21) can also be aligned relative to the coding areas (17) in the array, if instead the magnetic-field sensor (23) supplying the clock-pulse information is offset by half an array spacing with respect to the magnetic-field sensors (19) scanning the coding areas (17). In such a magnetic key arrangement, the key code of the magnetic key can be read serially using magnetic-field sensors of simple construction which, as the case may be, operate in an analog fashion. <IMAGE>
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