| 摘要 |
A data entry device durable enough to withstand the rigors of industrial type usage in which the electronic components are isolated from the external environment is described. The device comprises a molded elastomer keyboard matrix with thin stainless steel keypads. Embedded into the elastomer beneath the keys are small magnets. Solid state Hall-effect switches are mounted at a predetermined distance from the magnets and are separated from them by a magnetically permeable stainless steel sheet which forms part of the enclosure isolating the electronic components from the environment. Depressing one of the keys on the elastomer matrix moves its associated magnet toward the respective Hall-effect device, causing a change in current which may be sensed by other electronic components. Because of the elastomer material, the keys spring back when released.
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