HEATER SCALE

摘要

A heater-scale (10) having a curved supporting member (12) upon which a bag of fluid to be heated can be placed, has a distributed two-dimensional heating element (24) affixed to a lower surface thereof. The curved member (12) is supported by a load cell (16) for generating an electrical signal proportional to the weight of the bag on the heater member (10), a thermistor is in contact with the fluid whose temperature is to be maintained, a thermistor is affixed to the heater member, and a control system senses the weight and temperature of the bag of fluid as well as the temperature of the heater member for the purpose of nonlinearly adjusting the electrical current supplied to the heater element as fluid is removed from or variable temperature fluid is added to the bag so as to maintain the bag at a predetermined temperature.