摘要 |
An electronic autoclave cycle passively records the number of thermal cycles to which an instrument has been subjected in a steam autoclave. When a sterilization cycle has been completed, and the instrument is next energized in use, a microprocessor is employed to read the sensor and record the occurrence of a sterilization cycle. Information as to the cumulative number of cycles through which the instrument has been subjected is stored in a non-volatile memory. This data is suitably displayed on a display panel. The sensor employed uses either the Curie temperature or a temperature near but below the Curie temperature of a ferromagnetic material by first magnetizing the material and then, later, checking its flux density to determine whether a thermal cycle has occurred. In a first embodiment, a Hall effect sensor is used to directly measure the magnetic field strength of the magnetizable material. In a second embodiment, a sensor winding is used to sense the magnetic field strength of the magnetizable material. The sensor winding is interconnected with an amplifier so that changes in flux can be sensed.
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