To relieve excessive pressure in a sensor unit provided with a pressure sensor.
This unit is provided with a case 50 defining a recess part 55 storing a pressure sensor 60 and a pressure introduction passage 56 introducing detected pressure, and a sensor cover 70 connected to the case 50 to cover the recess part 55. An elastically deformable sensor seal ring 20 is interposed between the pressure sensor 60 and an inner wall surface of the recess part 55. An elastically deformable cover seal ring 130 is interposed between the sensor cover 70 and the case 50. The sensor cover 70 is joined to the case 50 by snap fitting, the sensor seal ring 120 and the cover seal ring 130 are compressed. Seal function is surely provided under normal pressure, and on the other hand, the sensor seal ring 120 and the cover seal ring 130 elastically deform and open a passage to release pressure when excessive pressure is applied. Consequently, breakage of the pressure sensor 60 can be prevented.
MIURA MIGAKU
NAMIBE KEISUKE
