US 12,449,394 B2
Gas sensor and gas sensor attached structure
Kunihiko Yonezu, Nagoya (JP); Yuji Shimazaki, Nagoya (JP); and Masayuki Yoshida, Nagoya (JP)
Assigned to Niterra Co., Ltd., Nagoya (JP)
Appl. No. 18/013,312
Filed by NGK SPARK PLUG CO., LTD., Nagoya (JP)
PCT Filed Apr. 22, 2021, PCT No. PCT/JP2021/016262
§ 371(c)(1), (2) Date Dec. 28, 2022,
PCT Pub. No. WO2022/091455, PCT Pub. Date May 5, 2022.
Claims priority of application No. 2020-181915 (JP), filed on Oct. 29, 2020.
Prior Publication US 2023/0273149 A1, Aug. 31, 2023
Int. Cl. G01N 27/407 (2006.01); G01M 15/10 (2006.01)
CPC G01N 27/4077 (2013.01) [G01M 15/102 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A gas sensor comprising:
a sensor element which extends in an axial direction and has a detection section formed in a forward end portion and configured to detect a gas to be detected;
a tubular metallic shell which surrounds a circumference of the sensor element in a radial direction and holds the sensor element; and
a single-wall tubular protector fixed to a circumference of a forward end portion of the metallic shell and surrounding the forward end portion of the sensor element, wherein
the protector has a gas introduction hole and a gas discharge hole disposed on a forward end side in relation to the gas introduction hole, and the protector further has a step portion which is formed to extend in the radial direction or formed to have an angle with respect to the radial direction, and the gas introduction hole is provided in the step portion;
the metallic shell has a fixing portion whose outer surface is fixed directly or indirectly to a pipe through which the gas to be detected flows, and a larger-diameter tool engagement portion located on a rear end side of the fixing portion adapted for fixing the gas sensor to the pipe;
a distance L1 in the axial direction between the gas introduction hole and the gas discharge hole is greater than a distance L2 in the axial direction between the tool engagement portion and the gas introduction hole; and
a forward end of the sensor element is located on the forward end side in relation to the gas introduction hole.