Ngk Insulators, Inc.

Koichi Masuda

Nobukazu Ikoma

Mika Murakami

Takashi Hino

Hironori Sakakibara

Hirohito Kiyota

Kenji Isaka

Yosuke Adachi

Miyoshi Makino

Shodai Hirata

Kazuhito Sakakibara

In a gas sensor, a powder compact seals a void space between an inner peripheral surface of metal-made main hardware and a sensor element, and the inner peripheral surface has arithmetic average roughness of 0.5 to 5 &#x3bc;m. The gas sensor includes supporters, which are arranged in a penetration hole of the main hardware, which allow the sensor element to penetrate therethrough, and which press the powder compact in sandwiching relation from both sides in an axial direction. A surface of at least one of the supporters has the arithmetic average roughness of not more than 0.5 &#x3bc;m.

Gas sensor

A sensor element includes an element body having an elongate rectangular parallelepiped shape and including solid electrolyte layers with oxygen ion conductivity, an outer pump electrode disposed on a first surface of the element body, and a protective layer covering at least a part of a second surface of the element body on a side opposite to the first surface and including one or more exposed spaces (a lower space) to which the second surface is exposed.

Sensor element and gas sensor

A sensor element includes an element body having an elongate rectangular parallelepiped shape and including solid electrolyte layers with oxygen ion conductivity, an outer pump electrode disposed on a first surface of the element body, and a protective layer covering at least a part of the first surface of the element body and including one or more exposed spaces (an upper space) to which the first surface is exposed.

A sensor element includes an element body having an elongate rectangular parallelepiped shape and including solid electrolyte layers with oxygen ion conductivity, an outer pump electrode disposed on a first surface of the element body, and a protective layer covering at least a part of the first surface of the element body and including one or more spaces (an upper space) that are present apart from the first surface in a direction perpendicular to the first surface.

A sensor element includes an element body having an elongate rectangular parallelepiped shape and including solid electrolyte layers with oxygen ion conductivity, an outer pump electrode disposed on a first surface of the element body, and a protective layer covering at least a part of a second surface of the element body on a side opposite to the first surface and including one or more spaces (a lower space) that are present apart from the second surface in a direction perpendicular to the second surface.

In a gas sensor, not only a tubecovers lead wires, but also the tubecovers an outer peripheral surface of an end portion of an outer cylinderincluding an open end. A portion of the outer peripheral surface of the outer cylindercovered with the tubeis gripped by a clamp. Thus, the clampintegrally grips the tubeand the outer cylinder. Moreover, the tubeprotrudes from the clampto a side of the outer cylinderopposite from the open end(protrusion amount L&#x3e;0). Further, the open endof the outer cylinderforms a large-diameter portion whose outer diameter is larger than an inner diameter Dof the clamp

Insulating grip and apparatus for a gas sensor

In a gas sensor, a powder compactseals a void space between an inner peripheral surfaceof metal-made main hardwareand a sensor element, and the inner peripheral surfacehas arithmetic average roughness Ra of 0.5 to 5 &#x3bc;m. The gas sensorincludes supportersand, which are arranged in a penetration hole of the main hardware, which allow the sensor elementto penetrate therethrough, and which press the powder compactin sandwiching relation from both sides in an axial direction. A surface of at least one of the supportersandhas the arithmetic average roughness Ra of not more than 0.5 &#x3bc;m.

A contact fitting has a supporting portion capable of contacting a surface of a sensor element, and a conducting portion protruding in the same direction as the supporting portion and capable of contacting an electrode on the sensor element. Before the contact fitting is attached to the sensor element, a protrusion height of the conducting portion is 90% to 110% of a protrusion height of the supporting portion, and the protrusion heights and are relatively close to each other. The supporting portion and the conducting portion are elastically deformable and are curved in shape. The supporting portion and the conducting portion are arranged along a longitudinal direction of the contact fitting.

Contact member and manufacturing method of sensor

In a holding portion of a contact fitting, in a state before crimping of core wires, the thickness of a first distal end portion and the thickness of a second distal end portion are both 70% or less of the thickness of the bottom portion. The thicknesses are both smaller than the diameter of core wires of a lead wire to be crimped. The first distal end portion and the second distal end portion are formed by compression processing. Using the holding portion, a first side portion and a second side portion are curved such that they face the bottom portion, and the plurality of core wires are surrounded and crimped with the bottom portion, the first side portion, and the second side portion.

Crimp terminal, crimp body, and method for manufacturing crimp body

To provide a gas sensor which can stably carry out a securement of an electric continuity between a sensor element and a contact member. A contact member in which an electric connection to a sensor element is obtained by pinching and fixing the sensor element in an inserting port formed by a pair of housing members includes a constraint member which is provided in an outer periphery of a pair of housing members. The constraint member constrains a displacement of a pair of housing members within a predetermined range before the sensor element is pinched and fixed by a pair of housing members, and exists in a state of being pinched between the annular member and a pair of housing member without generating any reaction force with respect to the external force, after the sensor element is pinched and fixed.

Contact member for gas sensor, gas sensor, constraint member, connecting method of sensor element and contact member of gas sensor, manufacturing method of gas sensor

In a gas sensor, when an arithmetical mean roughness Ra of an inner periphery of a metal tubeis 1 &#x3bc;m or less and end portionsandof U-springsare formed as curved contact portions, the end portionsandof the U-springscan slide smoothly along the inner periphery of the metal tube. Therefore, when vibration is applied to the gas sensor, the U-springscan be prevented from being caught in the inner periphery of the metal tube, and the vibration can be absorbed by an elastic function of the U-springs. Even if the gas sensor vibrates, defective contact between a sensor elementand contact fittingsand wear and cracks in the sensor elementare less likely to occur. That is, the gas sensor resistant to vibration can be obtained.

Gas sensor and method for making the same

In a contact member for a gas sensor configured to fix a sensor element by sandwiching the sensor element in an insertion port defined by a pair of housing members to thereby obtain electrical connection with the sensor element, a restraint member provided at an outer circumference of the pair of housing members and having a restraint function for restraining a displacement of the pair of housing members within a predetermined range is used. The restraint member includes: two pressing surface portions to which a compression force that occurs when the annular member shrinkingly deforms is applied; a first side portion coupled perpendicularly to the two pressing surface portions; and a second side portion having an upper side portion coupled perpendicularly to one of the pressing surface portions and a lower side portion coupled perpendicularly to the other of the pressing surface portions.

Contact member for a gas sensor, method for connecting a contact member with a sensor element in a gas sensor, and method for manufacturing a gas sensor

Each of contact fittings is obtained by bending a die-cut member having a metal plate portion of substantially rectangular shape and a metal piece connecting to a long side of the metal plate portion. The metal piece is folded to be accommodated within a region directly above a surface of the metal plate portion opposite a surface in contact with a front-surface electrode or a back-surface electrode. Then, the metal piece is bent along the length of the metal plate portion to form a hook to be retained by a first housing or a second housing. Therefore, as compared to a structure in which hooks are orthogonal to the length of metal plate portions and bend outward from contact fittings, the arrangement width of the contact fittings arranged in a direction substantially orthogonal to the length of the contact fittings can be reduced.

Growing community of inventors

Nagoya, Japan

Koichi Masuda