MAGNETIC ELEMENT TEMPERATURE SENSORS

摘要

Small, low-cost wireless temperature sensors (26, 64, 96) are provided for sensing the temperature of an object (44). The temperature sensors (26, 64, 96) preferably include a plurality of individual, magnetically susceptible temperature sensor elements (28-34, 66, 92), as well as optional magnetic field-responsive data elements (38, 40, 20) adapted for attachment to object (44) or to a substrate (82) in turn attached to object (44). The temperature sensor elements (28-34, 66, 92) preferably have magnetic bodies (22, 70) exhibiting a re-magnetization response under the influence of an applied alternating magnetic field, which is different below and above a set point temperature, normally the Curie temperature of the magnetic body (22) or an adjacent sheath (74, 94). The temperature sensors (26, 64, 96) are used in conjunction with a detector (46) operable to generate a magnetic field of magnitude sufficient to cause re-magnetization responses of the temperature sensor elements (28-34, 66, 92) and optional data elements (38, 40, 20), to detect such responses, and to use the detected responses to determine the temperature of object (44) by means of a decoding algorithm. The temperature sensors (26, 64, 96) can be used in closed-loop heating systems (98) capable of controlling the heating of an object (114).