发明名称 |
AIR FLOW DETECTION APPARATUS |
摘要 |
An air flow detection apparatus useful in operating an accessory item in an HVAC system includes a sensor printed circuit board assembly having a first thermistor adapted to be exposed to an air flow and associated with a first pair of heating resistors. A second thermistor is placed in parallel with the first thermistor and is adapted to be hidden from the air flow and is associated with a second pair of heating resistors. A control printed circuit board assembly is interconnected with the sensor printed circuit board assembly and has a voltage regulator circuit for applying a DC voltage source to a power regulator circuit and a sensor monitoring circuit interfaced therewith . The power regulator circuit enables the first thermistor and the second thermistor to be heated to a target temperature greater then a highest specified operating ambient temperature and maintains a temperature of the second thermistor regardless of the actual ambient temperature, and the sensor monitoring circuit responds to the cooling of th e first thermistor in the presence of air flow to output a signal operating the HVAC accessory item.
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申请公布号 |
CA2375950(A1) |
申请公布日期 |
2002.10.26 |
申请号 |
CA20022375950 |
申请日期 |
2002.03.11 |
申请人 |
RESEARCH PRODUCTS CORPORATION |
发明人 |
THOMPSON, LUKE P. |
分类号 |
G01F1/684;G01F1/696;(IPC1-7):F24F11/02 |
主分类号 |
G01F1/684 |
代理机构 |
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