| 摘要 |
<p>An oxygen concentration sensor comprises a sensor element (10) with a gas-sensing portion (11) formed at a distal end (10a) thereof. The gas-sensing portion (11) is surrounded by cup-like inner and outer covers (31, 32) that have bottoms (311, 321) facing the distal end (10a) of the sensor element (10). The outer cover (32) is provided with a gas hole (23) only at the bottom (321) thereof. The gas hole (23) introduces the gas inside the outer cover (31). A flowing direction of the gas is substantially perpendicular to the axial direction of the oxygen concentration sensor (1). Thus, in the gas stream, unburned substances flow in parallel with the opening of gas hole (23). As a result, the amount of the unburned substances deposited in the vicinity of the gas hole (23) can be reduced greatly. And, the amount of the unburned substances passing through the gas hole (23) can be reduced greatly. <IMAGE> <IMAGE></p> |
