Abstract: A gas sensor including a detecting element; and a protector having a tube portion surrounding the detecting portion, and a bottom portion the protector having a first opening disposed at the tube portion and a second opening at the bottom portion. The bottom portion includes first and second bottom wall portions, the second bottom wall portion protrudes toward the leading end side, and at least a part of the inner face thereof is located at the leading end side with respect to the outer face of the first bottom wall portion. The second opening is provided on a side opposite the inner space of the tube portion in a communication passage formed by the inner face of the second bottom wall portion, and an opening area of the second opening is larger than an area of the largest imaginary circle that can be placed inside the first opening.

Abstract: A gas sensor (200) includes a gas sensor element (10) extending in an axial direction (O), having a detection portion (11) provided at a front end thereof, and having electrode pads (12a) provided at a rear end thereof; connection terminals (31, 32) electrically connected to the respective electrode pads; and a cover (60, 61) covering the rear end of the gas sensor element and the connection terminals. The cover integrally has a connector portion (63) having an opening (63b) which allows an external connector to be inserted thereinto and removed therefrom in a predetermined direction, and has a connector terminal member (120) which can be inserted into the opening. The connector terminal member has a plurality of connector terminals (70) to be electrically connected to the respective connection terminals, and an insulator (121) integrally molded with the connector terminals. Also disclosed is a method for manufacturing the gas sensor.

Abstract: A gas sensor (200) includes a gas sensor element (10) extending in the direction of an axis O, and a housing (50) made of metal, radially surrounding the gas sensor element, and adapted for inserting at least partially into a sensor-mounting hole (350) of a mounting body (300). The gas sensor (200) further includes a resin member (60, 61) which radially surrounds the housing at least partially and having a contact portion (C) in contact with the housing that is at least partially disposed axially frontward with respect to the outer surface of the mounting body (300) around the sensor-mounting hole, and a heat sink member (80) that is in contact with the housing at an axial position the same as or located frontward of the axial position of the front end of the contact portion.

Abstract: A gas sensor (1) has an inner protector (120) and an outer protector (110); the inner protector (120) has an inner wall portion (160) having an inner gas inlet (170) for introducing gas to be measured into the interior of the inner protector (120); the outer protector (110) has an outer wall portion (130) having an outer gas inlet (140) for introducing the gas to be measured into the interior of the outer protector (110); a clearance of 1.35 mm or less is provided between the detection portion (11) and at least a portion of the inner wall portion (160); and when the gas sensor (1) is in use, the inner protector (120) is higher in temperature than the outer protector (110).

Abstract: A gas sensor including a gas sensor element that extends in an axial direction and has a detection section at a front-end side thereof, and an electrode pad at a rear-end side thereof; a connection terminal that is electrically connected to the electrode pad; and an insulated separator that extends along the axial direction and has an inserting hole into which the connection terminal is inserted. An element side section is arranged within the inserting hole and is connected the electrode pad, and an external circuit side section extends further to the outside in a diametrical direction than an outer surface of the separator through one or more first bending sections from the element side section.

Abstract: A sensor of the present invention includes a sensor element; a metallic shell; an outer tube member fixed to a rear end portion of the metallic shell; and a protective outer tube member covering an outer surface of the outer tube member. The outer tube member has a seal portion being circumferentially in contact with the protective outer tube member directly or via another member, and a front-side separation portion located frontward of the seal portion and spaced apart from and facing the protective outer tube member. A metal coating layer (plating layer) is formed on the outer surface of at least the front-side separation portion of the outer tube member.

Abstract: An intake system for an internal combustion engine includes an intake passage connected with an intake port of the internal combustion engine; an EGR passage merged with the intake passage at a junction portion; a gas sensor attached to the intake passage and configured to detect a concentration of specific gas; and a control section configured to control the internal combustion engine on the basis of an output signal of the gas sensor. A diameter-enlarged portion having an inner diameter larger than an inner diameter of the junction portion is formed at a portion of the intake passage which is located on a downstream side of the junction portion. The gas sensor is located downstream from the diameter-enlarged portion.

Abstract: A glow plug including a center pole extending along an axial direction; a heater including a heating element capable of generating heat upon energization, which heater is connected to a leading end portion of the center pole so as to constitute together with the center pole an integrated heater/center pole member in a mechanically rigid state; a metal shell as defined herein; and a vibration preventing member for preventing vibration of the center pole, the vibration preventing member being fixed on an outer peripheral surface of the center pole at an axial position corresponding to a portion where an inside diameter of the axial hole of the metal shell is constant.

Abstract: A sensor includes: a sensor element extending in an axial direction comprising a leading end portion exposed to a gas measurement object; a metal shell covering a periphery of the sensor element; an outer cylinder member fixed to a rear end side of the metal shell, the outer cylinder member being composed of a first metal material; and a protection outer cylinder member covering an outer surface of the outer cylinder member, the protection outer cylinder being composed of a second metal material. The outer cylinder member further includes a sealing part in contact with a circumference of the protection outer cylinder member, and a spaced part positioned closer to a leading end side than the sealing part, and spaced from the protection outer cylinder member. The first metal material is less subject to rusting than the second metal material.

Abstract: A gas sensor includes a plate-like sensor element having solid electrolyte layers; a circuit board having a processing circuit for processing an output signal from the sensor element; terminals connected to the sensor element and to the circuit board and serving as electric junctions therebetween; and a metallic casing which encloses the sensor element, the circuit board, and the terminals and has attachment portions for attachment to an external object. The attachment portions are attached to an inlet pipe at a position located downstream of an EGR gas inlet or to a cylinder head.

Abstract: A sensor comprising a sensor element, a metallic housing holding therewithin the sensor element, an inner tubular member fixed to an axially rearward end of the metallic housing, and an outer tubular member radially surrounding the inner tubular member and having a radially inward crimping section for contact with an outer surface of the inner tubular member, wherein an axially forward end of the crimping section is disposed axially apart from an axially forward end of the outer tubular member by a distance of 1.5 mm or less.

Abstract: A gas sensor is constructed as follows. A protector (4) covering around a gas sensing element (2) has an inner hollow-cylindrical portion (6) and an outer hollow-cylindrical portion (7) that is provided coaxially with the inner hollow-cylindrical portion (6) with an air space (8) in between. Outer-wall gas inlet openings (13) are formed in the outer hollow-cylindrical portion (7), and guiding bodies (10) extending inward are attached to the outer-wall gas inlet openings (13). Inner-wall gas inlet openings (11) are formed in the inner hollow-cylindrical portion (6) at positions nearer to the gas sensing element (2) than the outer-wall gas inlet openings (13). A side wall (9) face of the inner hollow-cylindrical portion (6) opposite the outer-wall gas inlet openings (13) is formed so as to be parallel to a side wall (12) of the outer-hollow cylindrical portion (7) or so as to have a slop-like shape with a diameter enlarging in the axial direction toward a bottom wall (17) of the protector (4).

Abstract: To provide a sensor characterized in that corrosion of an outer tube member by adhesion of salt water or the like is restrained, thereby preventing deterioration in detection accuracy of the sensor, which could otherwise result from penetration of salt water or the like into the interior of the outer tube member. A sensor 100 of the present invention includes a sensor element 2; a metallic shell 4; an outer tube member 11 fixed to a rear end portion of the metallic shell 4; and a protective outer tube member 12 covering an outer surface of the outer tube member 11. The outer tube member 11 has a seal portion A being circumferentially in contact with the protective outer tube member 12 directly or via another member, and a front-side separation portion R1 located frontward of the seal portion A and spaced apart from and facing the protective outer tube member 12. A metal coating layer (plating layer M) is formed on the outer surface of at least the front-side separation portion R1 of the outer tube member 11.

Abstract: An object is to provide a glow plug in which a gap can be prevented from being generated between a ceramic heater and a cylindrical member even at the time of use in an internal combustion engine, etc. so that electrical conduction of the glow plug can be prevented from being lowered. A glow plug includes: a rod-shaped ceramic heater 2; a rod-shaped center pole 5 extending axially so as to electrically connect to the outside; and a cylindrical member 100 having a front end portion 101 bonded to an outer circumferential surface 2a of a rear end side of the ceramic heater 2, and a rear end portion 102 bonded to an outer circumferential surface of a front end side of the center pole 5, the cylindrical member 100 being made by a metal material for electrically connecting one of a pair of lead portions and the center pole 5 to each other, the glow plug characterized in that the cylindrical member 100 has a Vickers hardness of not lower than 200 HV at 25° C.

Abstract: A glow plug including a center pole extending along an axial direction; a heater including a heating element capable of generating heat upon energization, which heater is connected to a leading end portion of the center pole so as to constitute together with the center pole an integrated heater/center pole member in a mechanically rigid state; a metal shell as defined herein; and a vibration preventing member for preventing vibration of the center pole, the vibration preventing member being fixed on an outer peripheral surface of the center pole at an axial position corresponding to a portion where an inside diameter of the axial hole of the metal shell is constant.

Abstract: A sensor comprising a sensor element, a metallic housing holding therewithin the sensor element, an inner tubular member fixed to an axially rearward end of the metallic housing, and an outer tubular member radially surrounding the inner tubular member and having a radially inward crimping section for contact with an outer surface of the inner tubular member, wherein an axially forward end of the crimping section is disposed axially apart from an axially forward end of the outer tubular member by a distance of 1.5 mm or less.

Abstract: An object is to provide a glow plug in which a gap can be prevented from being generated between a ceramic heater and a cylindrical member even at the time of use in an internal combustion engine, etc. so that electrical conduction of the glow plug can be prevented from being lowered. A glow plug includes: a rod-shaped ceramic heater 2; a rod-shaped center pole 5 extending axially so as to electrically connect to the outside; and a cylindrical member 100 having a front end portion 101 bonded to an outer circumferential surface 2a of a rear end side of the ceramic heater 2, and a rear end portion 102 bonded to an outer circumferential surface of a front end side of the center pole 5, the cylindrical member 100 being made by a metal material for electrically connecting one of a pair of lead portions and the center pole 5 to each other, the glow plug characterized in that the cylindrical member 100 has a Vickers hardness of not lower than 200HV at 25° C.

Abstract: A glow plug comprising: a ceramic heater which houses a heating element defined herein in a tip end side of said ceramic heater, and which elongates in an axial direction; a cylindrical metal shell which has a shaft hole, which houses a rear end portion of said ceramic heater in said shaft hole, and which holds said ceramic heater in said shaft hole directly or via another member; and a center pole including a center-pole rear end portion as defined herein and a center-pole tip end portion as defined herein, said ceramic heater being mechanically rigidly joined to said heater connecting portion, wherein a stress releasing portion in which a diameter is smallest in an area between said heater connecting portion and said center-pole rear end portion is formed in said center pole.

Abstract: A heater including: a rod-shaped ceramic heater including: a ceramic heater body extending in an axial direction and having a heating-element at its leading end portion for generating heat when energized; and first and second energizing lead terminals extending from the heating element and exposed to an outer circumference of a trailing end side of the ceramic heater body; a cylindrical outer cylinder for holding the ceramic heater while protruding a leading end portion and a trailing end portion of the ceramic heater; and a core rod arranged on said trailing end side of the ceramic heater in an axial direction and connected electrically with the first lead terminal, wherein the heater further includes: a ring member including: a ring leading end portion fixed by a tight fitting on an outer circumference of a trailing end side of the ceramic heater and connected electrically with the first lead terminal; and a ring trailing end portion protruding backward from a trailing end of the ceramic heater; and a metal

Abstract: A glow plug comprising: a ceramic heater which houses a heating element defined herein in a tip end side of said ceramic heater, and which elongates in an axial direction; a cylindrical metal shell which has a shaft hole, which houses a rear end portion of said ceramic heater in said shaft hole, and which holds said ceramic heater in said shaft hole directly or via another member; and a center pole including a center-pole rear end portion as defined herein and a center-pole tip end portion as defined herein, said ceramic heater being mechanically rigidly joined to said heater connecting portion, wherein a stress releasing portion in which a diameter is smallest in an area between said heater connecting portion and said center-pole rear end portion is formed in said center pole.