| 摘要 |
PURPOSE:To stabilize the measurement of gas concentration, by processing a porous material using impregnation liquid containing a component connected thereto to allow the control of the diffusion of a gas. CONSTITUTION:An air/fuel ratio sensor is equipped with an element (A) comprising electrodes a1 and b1 and a solid electrolytic plate 3, an element (B) comprising electrodes c4 and d5 and a solid electrolytic plate 6, an internal reference oxygen, source (R) comprising the electrode a1 formed as a buried porous electrode at a lap between the element (A) and a shielding body 7, a leak resistance section comprising a porous insulator Z with one end thereof contacting a lead of the electrode a1 and the other end thereof through hole of a porous electrode b2 and a lead section of the electrode b2 and a measuring gas chamber 9 formed between the electrodes b2 and c4 as opposed by laminating the elements (A) and (B) through a spacer 8 as lamellar intermediate member. Then, the spacer 8 is replaced at four points with porous material to make a gas diffusion restricting section T. When the porous material is treated by an impregnating liquid, the pore will be reduced to enhance the gas diffusion restricting effect. |
