Patent ID: 11885763
Assignee: ROHM CO., LTD.
Field: Measurement (Instruments)
Classification: CPC G  Y | IPC G

Claim 0:
1. A gas concentration measurement system, comprising:
a limiting current-type gas sensor;
a voltage source connected to the limiting current-type gas sensor;
a current detector connected to the limiting current-type gas sensor; and
a gas concentration arithmetic unit connected to the current detector, wherein
the voltage source is configured to supply a first voltage and a second voltage higher than the first voltage to the limiting current-type gas sensor,
the first voltage generates a first limiting current corresponding to a first gas in the limiting current-type gas sensor,
the second voltage generates a second limiting current corresponding to a second gas in the limiting current-type gas sensor,
the current detector is configured to:
acquire a first limiting current value of the limiting current-type gas sensor when the first voltage is applied to the limiting current-type gas sensor; and
acquire a second limiting current value of the limiting current-type gas sensor when the second voltage is applied to the limiting current-type gas sensor,

the gas concentration arithmetic unit includes circuitry configured to:
acquire a difference between the second limiting current value and the first limiting current value; and
obtain a concentration of the second gas on a basis of the difference, a limiting current-type gas sensor element comprising:
a solid electrolyte,
a first electrode disposed on the solid electrolyte,
a second electrode disposed on the solid electrolyte,
an insulating layer between the second electrode and the solid electrolyte, and
a gas introduction path is a layer extending between a first part of the first electrode opposed to the solid electrolyte and a gas inlet,

the insulating layer is disposed on each of:
an upper surface of the solid electrolyte,
a side surface of the solid electrolyte,
a side surface of the first electrode, and
a side surface of the gas introduction path, and

the insulating layer includes an opening in which a second part of the second electrode contacts the solid electrolyte.