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 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 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: 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 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 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: 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.