Parkhurst & Oliff
Oxygen sensor
 An oxygen sensor for determining an oxygen partial pressure of a measurement gas in a measurement-gas space, includes an elongate planar sensing element, a tubular protective device, and a retainer housing. The sensing element has an oxygen detecting portion adjacent to one longitudinal end thereof, and electrical terminal contacts adjacent to the other longitudinal end thereof. The tubular protective device accommodates therein the sensing element, and includes a first protective covering for protecting at least an end portion of the sensing element which is located within the measurement-gas space and exposed to the measurement gas and which includes the oxygen detecting portion. The tubular protective device further comprises a second protective covering for covering the remaining portion of the sensing element which is not exposed to the measurement gas. The tubular protective device is attached by the retainer housing to a partition wall defining the measurement-gas space. The elongate planar oxygen sensing element has a length of at least 40 mm as measured from the partition wall to the said other longitudinal end. 
NGK Insulators, Ltd.
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inventional inventional inventional inventional
Takao Nobuhide
Murase Kato