Patent ID: 7341650

Claim:
A sensor comprising: a plate-type detection element having a detection portion formed at a front end portion directed to an object to be measured, and an electrode terminal portion formed at a rear end portion thereof; a first powder layer and a second powder layer circumferentially covering a portion of the plate-type detection element located between the detection portion and the electrode terminal portion; and a metallic shell having a through-hole for accommodating the first powder layer and the second powder layer, wherein the first powder layer is previously formed from a first powder-compacted ring having an annular shape, which is first attached to the element at a predetermined position located between the detection portion and the electrode terminal portion, and is then accommodated in the metallic shell together with the detection element; and the second powder layer is placed and compressed in the metallic shell on a rear-end side of the first powder layer so as to fill a space between the metallic shell and the detection element, after the first powder layer is accommodated in the metallic shell; said sensor further comprising a protection cover circumferentially covering the first powder layer which intervenes between the first powder layer and the metallic shell, wherein the protective cover circumferentially covers a side surface of the first powder layer, wherein a ceramic holder is disposed on the front end side of the first powder layer.