Abstract: A gas sensor includes a metal shell, a gas sensor element held in the metal shell, a metal portion arranged between a flange portion of the gas sensor element and a seat portion of the metal shell and a porous thermal spray layer formed on the gas sensor element. When viewed in cross section along the direction of an axis of the gas sensor, a corner of the metal portion axially overlaps in position with or radially outwardly protrudes from an outer surface of a part of the thermal spray layer located on a side surface of the flange portion and is brought into contact with the seat portion. A rear end-facing surface of the metal portion is brought into contact with an outer surface of the thermal spray layer at a position radially inside the side surface of the flange portion.

Abstract: A protector has a two-stage structure that includes a large-diameter portion and a small-diameter portion. The large-diameter portion includes a cylindrical first peripheral wall and a first front end wall. The small-diameter portion includes a cylindrical second peripheral wall connected to the first front end wall and a second front end wall connected to a front end portion of the second peripheral wall. Opening portions are not formed in the first and second peripheral walls. First opening portions, which are opened toward only first recessed portions and an inner surface of the first peripheral wall, are formed at the first front end wall. A second recessed portion and second opening portions, which are formed in the second recessed portion and are opened toward an inner surface of the second peripheral wall, are formed in the second front end wall.

Abstract: A gas sensor suppresses the deterioration of gas tightness caused by failure of a sealing material. The gas sensor includes: a housing; a sensor element arranged inside the housing; a sealing material filling a gap between the sensor element and the housing; an insulation member arranged on a proximal end side of the sealing material; and an annular metal ring arranged on a proximal end side of the insulation member. The sealing material, the insulation member and the metal ring are fixed under pressure by caulking from a proximal end side to a distal. A proximal-end facing surface of an inner peripheral portion of the metal ring is spaced apart from the caulking portion in an opposing region where an inner end of the caulking portion and the metal ring face each other in an opposed manner.

Abstract: A gas sensor includes a metal shell, a gas sensor element held in the metal shell, a metal portion arranged between a flange portion of the gas sensor element and a seat portion of the metal shell and a porous thermal spray layer formed on the gas sensor element. When viewed in cross section along the direction of an axis of the gas sensor, a corner of the metal portion axially overlaps in position with or radially outwardly protrudes from an outer surface of a part of the thermal spray layer located on a side surface of the flange portion and is brought into contact with the seat portion. A rear end-facing surface of the metal portion is brought into contact with an outer surface of the thermal spray layer at a position radially inside the side surface of the flange portion.

Abstract: A gas sensor, including a cylindrical outer tube; and a seal member disposed in the outer tube, the seal member including: a lead wire insert hole and an atmosphere communication hole extending in an axial direction thereof. The gas sensor further includes: a protection portion which covers the atmosphere communication hole from the rear end of the gas sensor in the axial direction, the protection portion having a protrusion which protrudes toward a rear side of the gas sensor, and has an opening smaller than an opening of the atmosphere communication hole, wherein the protrusion is disposed at a further front end side of the rear end surface of the seal member.

Abstract: A protector has a two-stage structure that includes a large-diameter portion and a small-diameter portion. The large-diameter portion includes a cylindrical first peripheral wall and a first front end wall. The small-diameter portion includes a cylindrical second peripheral wall connected to the first front end wall and a second front end wall connected to a front end portion of the second peripheral wall. Opening portions are not formed in the first and second peripheral walls. First opening portions, which are opened toward only first recessed portions and an inner surface of the first peripheral wall, are formed at the first front end wall. A second recessed portion and second opening portions, which are formed in the second recessed portion and are opened toward an inner surface of the second peripheral wall, are formed in the second front end wall.

Abstract: A gas sensor, including a cylindrical outer tube; and a seal member disposed therein, the seal member including: a lead wire insert hole and an atmosphere communication hole. The seal member has a groove extending outwards in a radial direction at a rear end-facing surface from the atmosphere communication hole while circumventing the lead wire insert hole, the groove having a cutout toward the front end of the seal member. The gas sensor further includes: a protection portion which covers the atmosphere communication hole; and an arm couples the protection portion and the outer tube, and extends in the radial direction, the arm being at least partially disposed in the groove of the seal member. and the arm is disposed so as to define a gap with the bottom surface of the groove.

Abstract: A gas sensor includes an inner electrode formed on an inner surface of a base body. The inner electrode has an inner sensing portion formed in a gas contact inner region such that the inner sensing portion is located on the whole of a heat-facing area of the gas contact inner region facing a heating portion in a radial direction of the base body, a terminal contact portion formed in a rear end region such that the terminal contact portion is located in at least a part of the rear end region in a circumferential direction of the base body and a lead portion formed only on a part of the inner surface of the base body in the circumferential direction of the base body so as to connect the inner sensing portion and the terminal contact portion to each other.

Abstract: [Objective] To provide a gas sensor in which a filter member provided in an aerial communication hole adapted to introduce the air for exposing a reference electrode of a detection element to the air is reliably protected through simple configuration. [Means for Solution] A filter member 87 having air permeability and waterproofness is disposed in an aerial communication hole 91 formed in a grommet 9 disposed in a rear end portion 38 of a housing tube 3. The housing tube 3 has a vent portion 34 provided for ensuring aerial communication while protecting the filter member 87. The vent portion 34 is connected, by means of arm portions 33, to an end portion (an opening end 32) of a side wall 39 of the housing tube 3. The side wall 39 surrounds the circumference of the grommet 9. Since the arm portions 33 are disposed in respective grooves 93 of the grommet 9, the grommet 9 is positioned relative to the housing tube 3.

Abstract: A gas sensor includes an inner electrode formed on an inner surface of a base body. The inner electrode has an inner sensing portion formed in a gas contact inner region such that the inner sensing portion is located on the whole of a heat-facing area of the gas contact inner region facing a heating portion in a radial direction of the base body, a terminal contact portion formed in a rear end region such that the terminal contact portion is located in at least a part of the rear end region in a circumferential direction of the base body and a lead portion formed only on a part of the inner surface of the base body in the circumferential direction of the base body so as to connect the inner sensing portion and the terminal contact portion to each other.

Abstract: A sensor including a tubular casing having an open rear end; and a first elastic member having a through hole so as to introduce ambient air into the casing and disposed so as to block the rear end opening of the casing.

Abstract: A gas sensor including a detection element having a detection portion; a metal shell that surrounds the detection element so as to expose the detection portion to a measured atmosphere; an outer tube that is fixed to the metal shell so as to cover a rear end side of the detection element; and a seal member that is contained inside the outer tube, the seal member having a lead wire insertion hole and a through hole that penetrates in the axial direction; a tubular holding member made of a resin having a lower coefficient of thermal expansion than the seal member, the tubular holding member being held inside the through hole, the tubular holding member having a ventilation hole; and a filter that covers the ventilation hole, the filter being joined to the holding member, the filter blocking water from passing therethrough, and the filter having air permeability.

Abstract: A gas sensor suppresses the deterioration of gas tightness caused by failure of a sealing material. The gas sensor includes: a housing; a sensor element arranged inside the housing; a sealing material filling a gap between the sensor element and the housing; an insulation member arranged on a proximal end side of the sealing material; and an annular metal ring arranged on a proximal end side of the insulation member. The sealing material, the insulation member and the metal ring are fixed under pressure by caulking from a proximal end side to a distal. A proximal-end facing surface of an inner peripheral portion of the metal ring is spaced apart from the caulking portion in an opposing region where an inner end of the caulking portion and the metal ring face each other in an opposed manner.

Abstract: A gas sensor unit including: a gas sensor which includes a gas detection element, a sensor terminal and a cylindrical surrounding body which surrounds a periphery of the rear end of the sensor terminal; and a sensor cap. The sensor cap includes a cap terminal and a cap body which has an insertion hole surrounding a part of the rear end of the surrounding body. The cap body is formed of a resin, and a cap body seal surrounding the surrounding body is fitted into the insertion hole. The cap body includes a rear end seal pressing portion that contacts a rear end side surface of the cap body seal; and a leading end seal pressing portion that contacts a leading end side surface of the cap body seal, which holds the cap body seal.

Abstract: A gas sensor has a sensor element, extending axially, that detects a particular gas component in a gas under measurement, a metal housing causing the end of the sensor element to protrude farther than the end thereof to expose it to the gas under measurement and that surrounds the periphery of the sensor element and an outer tube disposed at the rear end inside the metal housing and a seal member that is disposed farther to the rear than the detection element and also inside the rear end of the outer tube, and that has formed therein a atmosphere-introduction hole passing therethrough in the axial direction, the gas sensor further having a crimped part, formed in the outer tube, for the purpose of holding the seal member a hollow-cylindrical member in contact with the inner peripheral surface of the atmosphere-introduction hole so as to oppose the crimped part, and a metal filter that joins to the hollow-cylindrical member at the rear end of the hollow-cylindrical member and also farther to the rear than the

Abstract: The present invention relates to improvement in the corrosion resistance of a weld joint between a metal shell and an outer casing. As a solution to this object, a metal shell 11 and an outer metal casing 16 are laser welded to each other via a weld joint 100 by irradiating a laser beam onto the entire circumference of a crimped area 90 in a circumferential direction of the outer metal casing 16. This laser welding operation is performed at a plurality of positions (two positions) displaced from each other in the direction of an axis O so that the weld joint 100 is formed with a front weld zone 110 and a rear weld zone 120.

Abstract: A gas sensor, including a cylindrical outer tube; and a seal member disposed in the outer tube, the seal member including: a lead wire insert hole and an atmosphere communication hole extending in an axial direction thereof. The gas sensor further includes: a protection portion which covers the atmosphere communication hole from the rear end of the gas sensor in the axial direction, the protection portion having a protrusion which protrudes toward a rear side of the gas sensor, and has an opening smaller than an opening of the atmosphere communication hole, wherein the protrusion is disposed at a further front end side of the rear end surface of the seal member.

Abstract: A gas sensor, including a cylindrical outer tube; and a seal member disposed therein, the seal member including: a lead wire insert hole and an atmosphere communication hole. The seal member has a groove extending outwards in a radial direction at a rear end-facing surface from the atmosphere communication hole while circumventing the lead wire insert hole, the groove having a cutout toward the front end of the seal member. The gas sensor further includes: a protection portion which covers the atmosphere communication hole; and an arm couples the protection portion and the outer tube, and extends in the radial direction, the arm being at least partially disposed in the groove of the seal member. and the arm is disposed so as to define a gap with the bottom surface of the groove.

Abstract: A gas sensor having an axis including a detecting element; a metal shell; an outer cylinder; and a plug member, as defined herein, and the gas sensor includes a first protective member that covers an air vent of the plug member so as to protect the filter member, the protective member having a ventilation portion having an opening smaller than an opening of the air vent and at least partially overlapping the air vent in the axial direction, and at least one of the outer cylinder and the plug member is provided with a locking portion that limits rotation of the protective member around the axis.

Abstract: A gas sensor extending along an axial direction, the gas sensor including: a housing having a through hole, the through hole including an expanding portion at a leading end thereof; a gas sensing element inserted into the housing, having a closed leading end, and provided with a sensor electrode on an outer surface of the leading end side thereof; a heater inserted into the gas sensor, and including a contact portion where the heater contacts an inner surface; an protector fixed on the leading end side of the housing and having an outer protector including an outer air hole and an inner protector being positioned within the outer protector and spaced apart from the outer protector in the radial direction; and an inner air vent provided between the inner protector and the leading end of the housing.