Gas sensor manufacturing method, gas sensor, and protective cover
AssigneeNGK Insulators, Ltd.
InventorToshiaki Kuno
Life of this patent
Estimating the term…
Abstract
In a method for manufacturing a gas sensor, a casing for holding a sensor element and a protective cover are connected to each other so that a distal end portion of the sensor element is covered with the protective cover. A first gas chamber, a sensor element chamber, and a second gas chamber into which gas is introduced from the outside are formed between the protective cover and the casing. In the gas introduction portion including the first gas chamber, the sensor element chamber, and the second gas chamber, there is no joint portion formed by welding.
Claims13
A method for manufacturing a gas sensor including a casing, a sensor element held by the casing, and a protective cover configured to protect a distal end portion of the sensor element that protrudes from the casing,
- wherein the protective cover includes an inner member disposed in the casing so as to surround the distal end portion of the sensor element, and an outer member disposed in the casing so as to cover the distal end portion of the sensor element and the inner member,
- the method comprising:
- forming the protective cover by fitting the inner member and the outer member to each other by press fitting;
- and
- connecting the outer member and a side surface of the casing to each other, connecting the inner member and the side surface of the casing to each other, and fixing by welding a connection portion between the outer member and the side surface of the casing, in a manner so that the distal end portion of the sensor element is covered with the protective cover, wherein
- a gas is introduced from outside into a space surrounded by the protective cover and the casing.
A gas sensor comprising:
- a casing;
- a sensor element held by the casing;
- and
- a protective cover configured to protect a distal end portion of the sensor element that protrudes from the casing, wherein
- the protective cover includes an inner member disposed in the casing so as to surround the distal end portion of the sensor element, and an outer member disposed in the casing so as to cover the distal end portion of the sensor element and the inner member,
- the protective cover is formed by fitting the inner member and the outer member to each other by press fitting,
- the distal end portion of the sensor element is covered with the protective cover by connecting the outer member and a side surface of the casing to each other, connecting the inner member and the side surface of the casing to each other, and fixing by welding a connection portion between the outer member and the side surface of the casing, and
- a gas is introduced from outside into a space surrounded by the protective cover and the casing.
A protective cover that protects a distal end portion of a sensor element held by a casing, the protective cover comprising:
- an inner member disposed in the casing so as to surround the distal end portion of the sensor element;
- and
- an outer member disposed in the casing so as to cover the distal end portion of the sensor element and the inner member, wherein
- the protective cover is formed by fitting the inner member and the outer member to each other by press fitting,
- the inner member and the outer member are connected by being fitted to each other,
- the outer member is connected to a side surface of the casing,
- the inner member is connected to the side surface of the casing, and
- a connection portion between the outer member and the side surface of the casing is fixed by welding.
Dependencies are inferred from the claim text.