| 摘要 |
PURPOSE:To obtain a miniaturized light wt. oxygen concn. detector, by providing a plug having a gas diffusion rate limiting hole to the opening end part of a cup shaped oxygen concn. detection element and forming a measuring chamber by connecting a heat resistant gas conduit for introducing gas to be measured and providing an air permeable buffer material between the conduit and the plug. CONSTITUTION:Pt electrodes 14, 15 are attached to the inner and outer surfaces of a cup shaped element main body 12 comprising an oxygen ion permeable electrolyte such as zirconia and a plug 3 having a gas diffusion rate limiting hole 13a, on which a platinum lead wire was printed, is provided to the opening end part of the main body 12 so as to be connected to an inside electrode 14. A heat resistant gas conduit 21 made of ceramic is received in the plug 13 and a buffer material 26 comprising porous ceramics is received in the connection part with the element 11 to form a measuring chamber 28 between the buffer material 26 and the plug 13 and gas to be measured is introduced into said measuring chamber 28 from the upper side passage 23 formed by the partition wall 22 provided to the pipe 21 to be exhausted from a lower side passage 24. By this structure, an oxygen concn. sensor is constituted and connected by a simple connector in a freely detachable manner to obtain a portable detector eliminated from an accident due to the deterioration of the gas conduit 21. |
