SENSOR UNIT FOR UREA TANK HAVING RETURN PIPE FOR THAWING FROZEN WATER

摘要

The present invention relates to a sensor unit which is mounted at an urea storage tank of an SCR type exhaust gas post-processing system, and to an improved sensor unit for an urea tank which can correctly measure a level or temperature of urea within the storage tank in real time, can prevent a the urea from freezing during the winter season or in cold weather, and can immediately supply the urea to a dosing unit by rapidly thawing the frozen urea if the urea is in a frozen state. The present invention can rapidly thaw the frozen urea around an urea suction pipe by particularly increasing the length of a urea return pipe to arrange the urea return pipe near the urea suction pipe and injecting the heated urea through a plurality of nozzles formed at an outer circumference thereof, and can rapidly and efficiently thaw the frozen urea in the initial cold stage by electrically heating the urea suction pipe or a heating pipe.