JP2018132407A - Gas sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas sensor having a terminal metal fitting connected to a lead wire in advance and inserted into a separator, so as to improve productivity of the gas sensor and to prevent the terminal metal fitting from being detached toward the rear end of the gas sensor.SOLUTION: A gas sensor 200 comprises an element 10 having an electrode pad 11, a terminal metal fitting 21 connected to the electrode pad 11, a lead wire 146, and a separator 166. The terminal metal fitting 21 includes: a main body part 21a; a lock part 21f which bends in a radial direction D and along a surface S perpendicular to a direction of an axial line O; and a flange part 21d which has a first tip-facing surface 301. The separator 166 includes: a shelf part 166a which is communicated with an insertion hole 166h and has a first rear-facing surface 302; and a second tip-facing surface 303 which is communicated with the insertion hole 166h. At a side closer to the tip than the second tip-facing surface 303, the lock part 21f protrudes to the outside of the insertion hole 166h in the radial direction D. A second rear-facing surface 304 of the lock part 21f abuts on the second tip-facing surface 303, and the first tip-facing surface 301 of the flange part 21d abuts on the first rear-facing surface 302 of the shelf part 166a. Thereby the terminal metal fitting 21 is prevented from being detached toward the tip end and the rear end of the gas sensor 200.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a gas sensor including a sensor element that detects the concentration of a gas to be detected.

As a gas sensor for detecting the concentration of oxygen or NOx in exhaust gas of an automobile or the like, one having a sensor element using a solid electrolyte is known.
As this type of gas sensor, an electrode pad is provided on the rear end side of the plate-like sensor element, and a separator (insulating member) is disposed so as to surround the radially outer side of the rear end side of the sensor element, and the insertion hole of the separator A terminal holding a metal terminal is used (Patent Document 1). The terminal fitting is electrically connected to the electrode pad of the sensor element, and the rear end side of the terminal fitting is caulked to the lead wire so that the sensor output signal from the sensor element can be taken out via the lead wire. ing. The lead wire is pulled out through a rubber grommet disposed on the rear end side of the gas sensor.
Also, the terminal fitting is provided with a plate-shaped retaining part, and when the lead wire pulled out of the gas sensor is pulled to the rear end side when the gas sensor is used, the rear facing surface of the retaining part is the tip of the separator. It contacts the facing surface to prevent the terminal fitting from coming out to the rear end side.

This gas sensor is assembled as follows. First, the terminal metal fitting is disposed on the front end side of the separator, the lead wire is passed through the insertion hole from the rear end side of the separator, and the front end side of the lead wire is caulked and connected to the rear end side of the terminal metal fitting.
Next, pull the lead wire on the rear end side of the separator to the rear end side until the retaining portion of the terminal metal fitting is caught on the surface facing the front end of the separator, and insert the terminal fitting from the front end side of the separator insertion hole into the insertion hole. Accommodate.

JP 2013-181769 A (FIGS. 8 and 10)

However, the operation of passing a soft lead wire through the insertion hole of the separator is complicated and causes a reduction in productivity. Therefore, productivity can be improved by passing a terminal fitting, to which a lead wire is connected in advance, from the rear end side of the separator through the insertion hole. However, in the case of the conventional terminal fitting, since the retaining portion to the rear end side interferes, it is impossible to insert the terminal fitting from the rear end side of the separator into the insertion hole.
Therefore, as shown in FIG. 10, it is assumed that a spring-like retaining portion 500 b is provided on the terminal fitting 500. The retaining portion 500b extends in the direction of the axis O, and can be bent in the direction of the axis O and the radial direction D with the tip end in the axis O direction serving as a fixed end and the rear end serving as a free end. The retaining portion 500b is accommodated in the radial direction D inside the insertion hole 1000h of the separator 1000, and is expanded in the radial direction D by the step portion 1000d extending radially outward from the insertion hole 1000h. It catches on the tip facing surface 1000a.
Therefore, when the lead wire 600 is caulked and connected to the rear end side of the terminal fitting 500 in advance and the terminal fitting 500 is inserted into the insertion hole 1000h from the rear end side of the separator 1000, the retaining portion 500b is accommodated in the insertion hole 1000h. The terminal fitting 500 and the lead wire 600 can be easily passed through the insertion hole 1000h.

However, if the terminal fitting 500 held by the separator 1000 is pulled toward the rear end side, the retaining portion 500b is bent by a relatively weak force, or is bent inward in the radial direction D, and the terminal fitting 500 comes off from the separator 1000. There was found. This is because the retaining portion 500b bends not only in the radial direction D but also in the axis O direction.
On the other hand, if the spring force of the retaining part 500b is increased, the bending of the retaining part 500b and the terminal metal part 500 can be suppressed, but the insertion load of the terminal metal part 500 into the insertion hole 1000h of the separator 1000 is increased, and the productivity is increased. Will be reduced.

  Therefore, the present invention has an object to provide a gas sensor that improves productivity by inserting a terminal metal fitting, to which a lead wire is connected in advance, into an insertion hole of a separator and suppresses the terminal metal from coming out to the rear end side. And

  In order to solve the above-described problems, a gas sensor according to the present invention extends in the axial direction, has a detection portion on the front end side, and has a sensor element having an electrode pad on the outer surface on the rear end side, and extends in the axial direction, the electrode A terminal fitting electrically connected to the pad, a lead wire electrically connected to the rear end side of the terminal fitting and drawn out to the rear end side from the terminal fitting, and an insertion hole extending along the axial direction And a cylindrical separator that accommodates the terminal fitting in the insertion hole and surrounds the electrode pad of the sensor element, the terminal fitting extending in the axial direction. A plate-like main body portion supported in the insertion hole, a locking portion that is connected to the main body portion and is bent in a radial direction along a plane perpendicular to the axial direction, and connected to the main body portion. And before the main body A flange projecting in a radial direction and having a first tip-facing surface; and the separator communicates with the insertion hole and has a first rear-end facing surface; and a first communicating with the insertion hole. A second tip-facing surface, and the locking portion protrudes more radially outward than the insertion hole on the tip side than the second tip-facing surface of the separator. 2 The rear end facing surface is in contact with the second front end facing surface to prevent the terminal fitting from coming off to the rear end side, and the first front end facing surface of the flange is the first end of the shelf. The terminal fitting is in contact with the rear end-facing surface to prevent the terminal fitting from coming off to the tip side.

According to this gas sensor, since the locking portion bends in the radial direction, the terminal fitting to which the lead wire is connected in advance can be inserted into the insertion hole of the separator.
Moreover, although a latching | locking part bends in a radial direction along the surface perpendicular | vertical to an axial direction, it does not bend substantially in an axial direction. Therefore, when the second rear end facing surface of the locking portion is in contact with the second tip facing surface of the separator, the locking portion may be bent even if the terminal fitting is pulled to the rear end side, or the radially inner side Bending to the rear end side of the terminal fitting can be effectively prevented.
Further, the first tip-facing surface of the collar portion contacts the first rear-end facing surface of the shelf portion to prevent the terminal fitting from coming off to the tip side.

In the gas sensor of the present invention, the terminal fitting further includes a pressing portion that is connected to the main body portion on the opposite side of the locking portion across the main body portion in the radial direction and is bent in the axial direction, The pressing portion presses the wall surface of the insertion hole inside the insertion hole, and the flange portion is brought into contact with the wall surface of the insertion hole on the opposite side of the pressing portion with the main body portion sandwiched in the radial direction. Good.
According to this gas sensor, even if the terminal fitting is inserted in such a manner that the terminal fitting is shaken in the radial direction of the insertion hole (so that the flange portion moves away from the wall surface of the insertion hole), the pressing portion causes the flange portion to contact the wall surface of the insertion hole. The tip of the terminal fitting can be positioned in the radial direction, and the tip of the terminal fitting can be prevented from stepping off the electrode pad.

In the gas sensor according to the aspect of the invention, it is preferable that the flange portion is located on the rear end side with respect to the locking portion.
According to this gas sensor, since the engaging portion is located on the more distal end side, the notch from the leading edge of the separator is formed when the surface facing the leading end of the separator that is locked to the engaging portion is formed by the notched portion or the like. The length can be shortened, and the manufacture of the separator is facilitated.

In the gas sensor of the present invention, the second tip-facing surface of the separator is formed as a tip-facing surface of a notch portion in which a part of the separator is cut away from the leading edge of the separator toward the rear end. The length L1 of the notch in the axial direction is longer than the length L2 of the locking portion in the axial direction, and the locking portion is accommodated in the notch and is behind the leading edge of the separator. It is good to be arranged on the side.
According to this gas sensor, since the length L1 is longer than the length L2, the locking portion is completely accommodated in the axial direction in the notch portion, and the locking portion is disposed on the rear end side of the front end edge of the separator. The For this reason, the tip of the terminal fitting is closer to the electrode pad side in the axial direction, the pressing of the tip due to the spring property (elasticity) of the terminal fitting becomes stronger, and the electrical connection between the electrode pad and the terminal fitting is further increased. Stabilize.

In the gas sensor according to the aspect of the invention, it is preferable that the locking portion is formed integrally with the main body portion.
According to this gas sensor, the productivity of the terminal fitting is improved, the strength of the engaging portion connected to the main body is improved, and the terminal fitting can be further reliably prevented from coming off to the rear end side.

  According to the present invention, a gas sensor can be obtained in which productivity is improved by inserting a terminal fitting, to which a lead wire is connected in advance, into the insertion hole of the separator, and the terminal fitting is prevented from coming out to the rear end side.

It is sectional drawing which follows the longitudinal direction of the gas sensor which concerns on embodiment of this invention. It is a perspective view of a sensor element. It is a perspective view of a terminal metal fitting. It is a bottom view of the separator seen from the front end side. It is a cross-sectional perspective view of the separator in the axial direction. It is a bottom perspective view of a separator seen from the tip side. It is a figure which shows the state which started passing the terminal metal fitting through the insertion hole of the separator. It is a figure which shows the final state by which the terminal metal fitting was inserted to the predetermined depth of the penetration hole. It is sectional drawing which follows the AA line of FIG. It is a figure explaining the malfunction at the time of letting the terminal metal fitting which connected the lead wire beforehand to the penetration hole of a separator.

Hereinafter, embodiments of the present invention will be described.
1 is an overall cross-sectional view of a gas sensor (oxygen sensor) 200 according to an embodiment of the present invention along the longitudinal direction, FIG. 2 is a perspective view of a sensor element 10, FIG. 3 is a perspective view of a terminal fitting 21, and FIG. It is a bottom view of the separator seen from.
The gas sensor 200 is an oxygen sensor that detects the oxygen concentration in the exhaust gas of automobiles and various internal combustion engines.

In FIG. 1, the gas sensor 200 includes a cylindrical metal shell 138 having a threaded portion 139 formed on the outer surface for fixing to an exhaust pipe, and an axis O direction (longitudinal direction of the gas sensor 200: up and down direction in the figure). The sensor element 10 having a plate-like shape that extends, a cylindrical ceramic sleeve 106 disposed so as to surround the periphery of the sensor element 10 in the radial direction, and the inside of the insertion hole 166h penetrating in the axial direction are provided inside the sensor element. 10 is a ceramic cylindrical separator 166 that is disposed so as to surround the periphery of the rear end portion, and four terminal fittings 21 that are disposed between the sensor element 10 and the separator 166 (only two in FIG. 1). Is shown).
Moreover, the gas detection part 10a at the tip of the sensor element 10 is covered with a porous protective layer 20 such as alumina (see FIG. 2).

  The metal shell 138 is made of stainless steel, has a through-hole 154 that penetrates in the axial direction, and has a substantially cylindrical shape that has a shelf 152 that protrudes radially inward of the through-hole 154. The sensor element 10 is disposed in the through hole 154 so that the tip of the sensor element 10 protrudes from the tip of the sensor element 10. Further, the shelf portion 152 is formed as an inwardly tapered surface having an inclination with respect to a plane perpendicular to the axial direction.

In addition, inside the through hole 154 of the metal shell 138, an annular ceramic holder 151 made of alumina in a state of surrounding the circumference of the sensor element 10, a powder filling layer 156 (hereinafter also referred to as a talc ring), and the above-mentioned The ceramic sleeves 106 are laminated in this order from the front end side to the rear end side.
Further, a caulking packing 157 is disposed between the ceramic sleeve 106 and the rear end portion 140 of the metal shell 138. The rear end portion 140 of the metal shell 138 is crimped so as to press the ceramic sleeve 106 toward the distal end side via the crimping packing 157.

  On the other hand, as shown in FIG. 1, a metal (for example, stainless steel) 2 having a plurality of holes and covering the protruding portion of the sensor element 10 on the outer periphery of the front end side (lower side in FIG. 1) of the metal shell 138. An external protector 142 and an internal protector 143, which are heavy protectors, are attached by welding or the like.

An outer cylinder 144 is fixed to the outer periphery of the rear end side of the metal shell 138. Further, the opening on the rear end side (upper side in FIG. 1) of the outer cylinder 144 is electrically connected to the four terminal fittings 21 (only two are shown in FIG. 1) of the sensor element 10, respectively. A rubber grommet 170 in which lead wire insertion holes (not shown) through which four lead wires 146 (only two are shown in FIG. 1) are inserted is disposed.
Further, a through-hole 170h for introducing air serving as a reference atmosphere is formed at the center of the grommet 170 in the axis O direction, and a cylindrical filter fitting 172 is fitted into the through-hole 170h. A water-repellent filter 174 that is disposed between the through hole 170h and the filter fitting 172 so as to close the through hole 170h and allows air to pass therethrough (air permeability) but does not allow water to pass therethrough is retained. The atmosphere can be introduced into and out of the gas sensor 200 through the hole 170h.
A grommet 170 and a cylindrical holding member 175 are arranged in this order from the rear end side inside the outer cylinder 144, and the grommet 170 and the holding member 175 are caulked from the outside of the outer cylinder 144. A grommet 170 is held inside the outer cylinder 144.

  A separator 166 is disposed on the rear end side (upper side in FIG. 1) of the sensor element 10 protruding from the rear end portion 140 of the metal shell 138. The separator 166 is arranged around a total of four electrode pads 11 (only two are shown in FIG. 1) formed on the main surface on the rear end side of the sensor element 10. The separator 166 is formed in a cylindrical shape having an insertion hole 166h penetrating in the axial direction, and is provided with a flange portion 167 that protrudes radially outward from the outer surface. The separator 166 is held inside the outer cylinder 144 by the flange portion 167 coming into contact with the outer cylinder 144 via the holding member 169.

As shown in FIG. 2, the sensor element 10 has a plate shape extending in the direction of the axis O, the tip portion 10 s is a gas detection portion 10 a that detects the oxygen concentration, and the gas detection portion 10 a is a porous protective layer 20. Covered. The sensor element 10 itself has a known configuration, and although not shown, the gas detector having an oxygen ion permeable solid electrolyte body and a pair of electrodes, and the gas detector are heated and maintained at a constant temperature. And a heater unit.
Two electrode pads 11 are arranged in the width W direction on the rear end side of one main surface of the sensor element 10, and a sensor output signal from the gas detection unit 10 a is passed through a lead part (not shown). Output from the electrode pad 11. Two electrode pads 11 are also arranged in the width W direction on the rear end side of the other main surface provided so as to face the main surface, and power is supplied to the heater portion via a lead portion (not shown). It comes to supply.
Each electrode pad 11 has a rectangular shape elongated in the direction of the axis O, and can be formed as a sintered body mainly composed of Pt, for example.

FIG. 3 shows a perspective view of the terminal fitting 21. In this embodiment, as will be described later, the gas sensor 200 has four terminal fittings 21, but these four terminal fittings 21 are the respective vertices of rectangles in the separator 166 as shown in FIG. 4. The terminal fittings 21 adjacent to each other are arranged symmetrically, and the terminal fittings 21 on the diagonal line have the same shape. That is, there are two types of terminal fittings 21 in FIG. 3 and terminal fittings which are symmetrical with the terminal fitting 21 in the right direction in FIG. 3 (corresponding to the terminal fitting 21 on the right side in FIG. 4). Since it is substantially the same, only the terminal fitting 21 of FIG. 3 will be described.
As shown in FIG. 3, the terminal fitting 21 includes a plate-like main body portion 21 a that is substantially plate-shaped and extends in the direction of the axis O, and a front-end portion 21 b that is folded back from the front end edge of the main body portion 21 a toward the rear end. , A crimp terminal portion 21c connected to the rear end of the main body portion 21a, and a pair of flange portions bent in an L shape from both ends of the main body portion 21a between the crimp terminal portion 21c and the front end portion 21b in the axis O direction. 21d, a pressing portion 21e, and a locking portion 21f that protrudes in a radial direction from one end (left side in the drawing) in the width direction of the main body portion 21a on the tip side of the flange portion 21d.

Here, the pair of flange portions 21d are formed in an L shape between the crimp terminal portion 21c and the distal end portion 21b from both ends of the main body portion 21a toward the folding direction of the distal end portion 21b (the sensor element 10 side described later). It is a portion that is bent and further protrudes and extends in the radial direction from the rear end side of the bent portion toward the turning direction of the tip end portion 21b. Further, when viewed from the direction of the axis O, the pair of flange portions 21d extend in parallel with the main body portion 21a interposed therebetween, and the tip-facing surfaces 301 of the pair of flange portions 21d are flush with each other.
Of the bent portions from both ends of the main body portion 21a, one bent portion (right side in the figure) is cut toward the tip in the direction of the axis O, and the cut portion is the plate surface of the bent portion. A pressing portion 21e is formed in a piece shape so as to expand radially outward and toward the free end on the rear end side with reference to the fixed end on the front end side.
Thereby, the pressing part 21e is bent together in the axis O direction along the surface T parallel to the axis O direction and in the radial direction D intersecting with the axis O direction.

The locking portion 21f extends in a radial direction from one end in the width direction of the main body portion 21a (left side in FIG. 3), and the fixed end of the locking portion 21f is connected to the one end of the main body portion 21a. Therefore, the locking portion 21f bends in the radial direction D along the surface S perpendicular to the axis O direction, but does not substantially bend in the axis O direction except for slight deformation.
Further, a rear end facing surface 304 is formed in the locking portion 21f.

The crimp terminal portion 21c has a known cylindrical shape, and the lead wire 146 is electrically connected by inserting and crimping the lead wire 146 with the conductive wire exposed in the cylinder.
The front end edge of the front end portion 21b is folded back toward the rear end to form a free end. And the front-end | tip part 21b is pressed to the electrode pad 11 side by the spring property (elasticity) of the terminal metal fitting 21 itself, so that a reliable electrical connection is obtained between the electrode pad 11 and the terminal metal fitting 21. It has become.
The terminal fitting 21 can be manufactured, for example, by punching a single metal plate (Inconel (registered trademark), etc.) and then bending the tip portion 21b. However, the present invention is not limited to this.

FIG. 5 shows a sectional perspective view of the separator 166 in the direction of the axis O, and FIG. 6 shows a bottom perspective view of the separator 166 as seen from the front end side.
As shown in FIG. 4, a rectangular insertion hole 166 h passes through the center of the separator 166 in the axial direction. Further, four rectangular holes are integrally communicated with the insertion holes 166h on the radially outer side of the respective apexes of the rectangle of the insertion holes 166h, and the insertion holes 166h as a whole are substantially H-shaped when viewed from the axis O direction. Is formed. Then, the four terminal fittings 21 are inserted into the portions located at the respective vertices of the rectangle of the insertion hole 166h.

As shown in FIG. 5, the separator 166 is formed with a shelf portion 166 a that communicates with the insertion hole 166 h and has a rear end facing surface 302.
As shown in FIG. 6, the separator 166 has a tip-facing surface 303 that communicates with the insertion hole 166h. In the present embodiment, the front-facing surface 303 is formed as a front-facing surface of a notch 166s in which a part of the separator 166 is cut out from the front edge 166f of the separator 166 toward the rear end.
In FIG. 6, the length in the axis O direction of the notch 166s from the tip edge 166f is L1, and the length in the axis O direction of the locking portion 21f is L2.

  The front-facing surfaces 301 and 303 correspond to “first front-facing surface” and “second front-facing surface” in the claims, respectively, and the rear-facing surfaces 302 and 304 respectively correspond to “first-facing surfaces” in the claims. It corresponds to “1 rear end facing surface” and “second rear end facing surface”.

Next, with reference to FIGS. 7 to 9, a mode in which the terminal fitting 21 to which the lead wire 146 is connected in advance is passed through the insertion hole 166 h from the rear end side of the separator 166 will be described. FIG. 7 shows a state in which the terminal fitting 21 starts to pass through the insertion hole 166h from the rear end side of the separator 166, and FIG. 8 shows a final state in which the terminal fitting 21 is inserted to a predetermined depth of the insertion hole 166h. FIG. 9 shows a cross section taken along line AA of FIG.
7 (a) and 8 (a) are sectional perspective views of the separator 166 in the direction of the axis O, and FIGS. 7 (b) and 8 (b) are bottom views of the separator 166 as viewed from the front end side. The figure is shown.

As shown in FIG. 7A, when the terminal fitting 21 to which the lead wire 146 is connected is passed through the insertion hole 166h from the rear end side of the separator 166, the locking portion 21f does not hit the insertion hole 166h (so as not to interfere). ), The locking portion 21f is bent in the radial direction. In the present embodiment, the locking portion 21f protrudes in the radial direction from the near side of the paper surface of FIG. 7 toward the back, and collides with the wall surface of the insertion hole 166h on the back side of the paper surface.
Therefore, the locking portion 21f is bent in the radial direction toward the front of the sheet of FIG. 7A (from the top to the bottom in FIG. 7B), and the terminal fitting 21 is moved from the rear end side of the separator 166. It passes through the insertion hole 166h.
Actually, for example, the terminal fitting 21 is passed through the insertion hole 166h, and the whole of the terminal fitting 21 is inserted into the insertion hole 166h while being pushed in the radial direction toward the back of the paper surface of FIG. be able to.
On the other hand, when the terminal fitting 21 is passed through the insertion hole 166h, the pressing portion 21e is bent in the direction of the axis O and accommodated inside the insertion hole 166h, so that it does not collide (interfere) with the wall surface of the insertion hole 166h. It is inserted into the insertion hole 166h.

When the terminal fitting 21 is further inserted into the distal end side of the insertion hole 166h, as shown in FIGS. 5 and 9, the distal-facing surface 301 of the flange portion 21d on one side (the right side in FIG. 7A) becomes the separator 166. The insertion depth is defined by contacting the rear end facing surface 302 of the shelf 166a.
At this time, as shown in FIG. 8A, the locking portion 21f bent in the radial direction and accommodated in the insertion hole 166h is formed in the radial direction at the notch portion 166s on the distal end side from the distal facing surface 303. It is released and protrudes (expands diameter) outward in the radial direction from the insertion hole 166h. Then, the rear end facing surface 304 of the locking portion 21f contacts the front end facing surface 303 of the separator 166 (FIG. 9).
Further, at this time, the main body portion 21a of the terminal fitting 21 is pressed to the left side of the paper surface of FIG. 9 by the spring property (elasticity) of the terminal fitting 21 itself, and is pressed against the wall surface of the main body portion 21a insertion hole 166h. The locking part 21f is positioned.

As described above, since the locking portion 21f is bent in the radial direction, the terminal fitting 21 to which the lead wire 146 is connected in advance can be inserted into the insertion hole 166h of the separator 166.
The locking portion 21f bends in the radial direction along the surface S (see FIG. 3) perpendicular to the axis O direction, but does not substantially bend in the axis O direction. Therefore, when the rear end facing surface 304 of the locking portion 21f is in contact with the front end facing surface 303 of the separator 166, the locking portion 21f may be bent even if the terminal fitting 21 is pulled to the rear end side, or the radial direction Can be prevented from bending to the rear end side of the terminal fitting 21 effectively.
Furthermore, the tip-facing surface 301 of the flange portion 21d abuts against the rear-end facing surface 302 of the shelf 166a to prevent the terminal fitting 21 from coming off to the tip side.
Further, by being pressed against the wall surface of the main body portion 21a insertion hole 166h, the locking portion 21f is suppressed from moving to the right side of the paper surface of FIG. 9, and the locking portion 21f can be effectively prevented from coming off. .

In the present embodiment, the terminal fitting 21 has a pressing portion 21e that is connected to the main body portion 21a on the opposite side of the locking portion 21f across the main body portion 21a in the radial direction. The pressing portion 21e is bent in the direction of the axis O inside the insertion hole 166h and presses the wall surface of the insertion hole 166h. Then, as shown in FIG. 8B, the reaction force F1 is applied to the terminal fitting 21, and the wall surface of the insertion hole 166h opposite to the pressing portion 21e (the wall surface on the right side in FIG. 8B) The part 21d is brought into contact.
Thus, even if the terminal fitting 21 is inserted in such a manner that the terminal fitting 21 is shaken in the radial direction of the insertion hole 166h (so that the flange portion 21d moves away from the wall surface of the insertion hole 166h), the pressing portion 21e causes the flange portion 21d to pass through the wall surface of the insertion hole 166h. Therefore, the tip of the terminal fitting 21 can be positioned in the radial direction, and the tip of the terminal fitting 21 can be prevented from stepping off the electrode pad 11.

  In the present embodiment, the flange portion 21d of the terminal fitting 21 is located on the rear end side with respect to the locking portion 21f. As a result, the locking portion 21f is located on the more distal end side, and therefore, when the leading end facing surface 303 of the separator 166 locked to the locking portion 21f is formed by the cutout portion 166s or the like, the leading edge 166f of the separator 166 is formed. The notch length from can be shortened, and manufacture of the separator 166 becomes easy.

In the present embodiment, when the above-described length L1 is longer than the length L2, the locking portion 21f is completely accommodated in the notch 166s in the direction of the axis O, and the locking portion 21f is more than the leading edge 166f of the separator 166. Is also arranged on the rear end side.
Therefore, the tip 21b of the terminal fitting 21 approaches the electrode pad 11 side in the direction of the axis O, and the pressing of the tip 21b due to the spring property (elasticity) of the terminal fitting 21 becomes stronger. During this period, the electrical connection is further stabilized.

It goes without saying that the present invention is not limited to the above-described embodiment, but extends to various modifications and equivalents included in the spirit and scope of the present invention.
For example, the shape, the number, and the like of the main body portion, the locking portion, the flange portion, and the pressing portion of the terminal fitting are not limited to the above embodiment. The shape of the separator, the shape of the insertion hole or shelf of the separator, the number, etc. are not limited to the above embodiment.
Furthermore, examples of the gas sensor include an oxygen sensor, a full-range air-fuel ratio sensor, a NOx sensor, and the like.

DESCRIPTION OF SYMBOLS 10 Sensor element 10a Detection part 11 Electrode pad 21 Terminal metal fitting 21a Main body part 21d Bump part 21e Press part 21f Locking part 146 Lead wire 166 Separator 166a Shelf part 166f Separator tip edge 166h Insertion hole 166s Notch part 200 Gas sensor 3011 Front end facing surface 302 First rear end facing surface 303 Second front end facing surface 304 Second rear end facing surface O Axis S Surface perpendicular to the axial direction D Radial direction L1 Axial length of the notch L2 L2 of the locking portion Axial length

Claims (5)

A sensor element that extends in the axial direction, has a detection part on the front end side, and has an electrode pad on the outer surface on the rear end side;
A terminal fitting extending in the axial direction and electrically connected to the electrode pad;
A lead wire that is electrically connected to the rear end side of the terminal fitting and is drawn out to the rear end side of the terminal fitting;
A cylindrical separator having an insertion hole extending along the axial direction, containing the terminal fitting in the insertion hole and surrounding the electrode pad of the sensor element;
A gas sensor comprising:
The terminal fitting extends in the axial direction and is supported in the insertion hole, and is connected to the main body and bends in a radial direction along a plane perpendicular to the axial direction. A stop portion and a flange portion connected to the main body portion and projecting in the radial direction from the main body portion and having a first tip-facing surface;
The separator further includes a shelf portion that communicates with the insertion hole and has a first rear end facing surface, and a second front end facing surface that communicates with the insertion hole,
The locking portion protrudes more outward in the radial direction than the insertion hole on the tip side of the second tip-facing surface of the separator, and a second rear-end facing surface of the locking portion is the second tip. The terminal is brought into contact with the facing surface to prevent the terminal fitting from being pulled out to the rear end side, and the first tip-facing surface of the flange portion is brought into contact with the first rear-end facing surface of the shelf portion to thereby form the terminal. A gas sensor characterized by preventing the metal fitting from coming off to the tip side. The terminal fitting further includes a pressing portion that is connected to the main body portion on the opposite side of the locking portion across the main body portion in the radial direction and bends in the axial direction.
The pressing portion presses the wall surface of the insertion hole inside the insertion hole, and the flange portion is brought into contact with the wall surface of the insertion hole on the opposite side of the pressing portion with the main body portion sandwiched in the radial direction. The gas sensor according to claim 1, wherein:   The gas sensor according to claim 1, wherein the flange portion is located on a rear end side with respect to the locking portion. The second front-facing surface of the separator is formed as a front-facing surface of a notch part in which a part of the separator is cut out from the front edge of the separator toward the rear end.
The axial length L1 of the notch is longer than the axial length L2 of the locking portion, and the locking portion is accommodated in the notch and is longer than the leading edge of the separator. It arrange | positions at the rear-end side, The gas sensor as described in any one of Claims 1-3 characterized by the above-mentioned.   The gas sensor according to any one of claims 1 to 4, wherein the locking portion is configured integrally with the main body portion.

Images