JP2002296223A - Sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure mounting accuracy of a sensor and to facilitate its mounting work. SOLUTION: In this oxygen sensor 1, by the energizing force of a spring part 17 interlaid between a lead connection part 13 and an element contact part 15 of a lead frame 11, the lead frame 11 sticks firm to the sidewall of a separator sleeve 12, so that one terminal unit 10 is composed. Thereby, the lead frame 11 can be connected to a detection element 2 in a single operation by connecting the terminal unit 10 to the detection element 2. Since mounting of the detection element 2 to a main fitting 7 and electrical connection of the lead frame 11 to the detection element 2 are carried out in separate processes, the detection element 2 can accurately be mounted at a predetermined position of the main fitting 7 independently of the lead frame 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sensor which operates by fixing a detection element in a metal shell.

[0002]

2. Description of the Related Art The applicant has developed a gas sensor 100 as shown in FIG. 9, for example, as a connection terminal structure for extracting a signal from a sensor used in a high-temperature environment. That is, the gas sensor 100 includes a cylindrical metal shell 102 fixed to the exhaust pipe, a flat detection element 104 inserted into the metal shell 102, and a lower part of the metal shell 102 of the metal shell 102 for holding the detection element 104. The ceramic holder 106, the talc powder 108, the ceramic sleeve 110, and a plurality of lead frames 112 for extracting a detection signal of the detection element 104 are provided.

[0005] Of these, a substantially rectangular insertion hole is formed in the ceramic holder 106 and the ceramic sleeve 110 along the central axis along the cross-sectional shape of the detection element 104. The detection element 104 includes a ceramic holder 106, a talc powder 108, a ceramic sleeve 110, and a lead frame 11 disposed between the ceramic sleeve 110 and the ceramic holder 110, which are disposed from below the inside of the metal shell 102.
2 and is fixed to the metal shell 102.

[0004] The tip side (lower side in the figure) of this detecting element 104
Is formed with a detection unit 104a, and the detection unit 10
A plurality of electrode terminals 104b for extracting the detection signal generated at 4a are formed. One end of the lead frame 112 is connected to each electrode terminal 104b, and the other end is a lead wire 11 for extracting a detection signal to the outside.
6 is connected.

The lead frame 112 is formed by processing a long stainless steel plate or the like, and a corrugated portion 112a having relatively strong elasticity is formed at a portion in contact with the electrode terminal 104b of the detecting element 104. I have. Therefore, when the detecting element 104 is disposed on the ceramic sleeve 110, the electrode terminal 104b of the detecting element 104 abuts on the wavy portion 112a of the lead frame 112 and is firmly fixed by the elastic force.

On the outer periphery of the metal shell 102 on the rear end side,
The outer cylinder 118 is fixed by welding or the like, and the lead wire 1
16 is drawn out through the seal member 120 arranged inside the end of the outer cylinder 118. Then, the detection signal can be taken out of the gas sensor 100 via the lead wire 116.

[0007]

However, the gas sensor 100 having the above configuration has the following problems. First,
In the manufacturing process of the gas sensor 100, it is necessary to penetrate the lead frame 112 through the square hole provided in the ceramic sleeve 110. In this case, at the lower end of the lead frame 112, a locking portion 114 that locks to the lower end surface of the ceramic sleeve 110 is provided so as to extend outward for positioning with respect to the ceramic sleeve 110. For this reason, when inserting the lead frame 112 into the ceramic sleeve 110, a method of inserting the lead frame 112 from below the ceramic sleeve 110 with the upper end at the top is adopted, and the shape of the upper end of the lead frame 112 is It will be limited to a shape that can be inserted. Specifically, a lead wire 116 is attached to the upper end of the lead frame 112.
It is difficult to form a ring-shaped caulked portion that is generally employed for caulking and joining the tip end portions, and a joining method such as welding must be employed. Since the welding strength of the welded joint is lower than that of the caulked joint, there is a possibility that the resistance to vibration and impact is reduced.

Further, in the manufacturing process of the gas sensor 100, these are inserted into the square holes of the ceramic sleeve 110 with the detecting element 104 sandwiched between the lead frames 112.
The detection element 104 is also positioned by the locking of the locking portions 114 of the twelve. However, the clearance between the detection element 104 and the ceramic sleeve 110 at the time of insertion varies due to variations in the thickness of the detection element 104, the width of the square hole of the ceramic sleeve 110, and the like. Therefore, the extension of the wavy portion 112a when the lead frame 112 is inserted varies, and as a result, the insertion depth of the detection element 104 into the ceramic sleeve 110 varies. As a result, the protrusion dimension (position) of the detection unit 104a of the detection element 104 varies, which may adversely affect the characteristics of the gas sensor 100.

Further, in the case of the above configuration, the detecting element 104
To the ceramic sleeve 1 via the lead frame 112.
10 is assembled to the metal shell 102 in an unstable state that is fixed in the inside 10. For this reason, at the time of assembling the two, there is a possibility that the mounting error may increase due to inclination of the metallic shell 102 or the like. Also, lead frame 1 to be performed later
At the time of welding the lead 12 and the lead 12, the ceramic separator 119 hinders the workability.

[0010] Such a problem is not limited to gas sensors.
As long as the sensor has a similar configuration, it is considered that the same occurs with other sensors such as a temperature sensor and a flow sensor. The present invention has been made in view of such a problem, and an object of the present invention is to secure assembling accuracy of a sensor and to facilitate the assembling work.

[0011]

SUMMARY OF THE INVENTION In view of the above problems, a sensor according to claim 1 has a detecting portion on a lower end side and extracts a detection signal of the detecting portion on a side surface on an upper end side. A flat detection element having a plurality of electrode terminals formed thereon,
A lead wire for extracting the detection signal to the outside, an element contact portion that contacts an electrode terminal of the detection element, a lead connection portion connected to the lead wire, and a connection between the element contact portion and the lead connection portion And a lead frame having a connecting portion.

The connecting portion has a bent portion at a lower portion of the lead frame, and is provided between the connecting portion connected to the element contact portion via the bent portion and the element contact portion. An interposer is interposed. According to such a configuration, although the form of the lead frame is defined in relation to the interposed body, the detection element can be attached to the metallic shell independently of the lead frame. Therefore, the detection dimension of the detection section of the detection element described above is not affected by the shape or deformation of the lead frame, and the detection element can be accurately attached to a predetermined position of the metal shell. as a result,
The characteristics of the sensor can be kept constant without the problem that the protrusion dimensions of the detection section of the detection element vary.

Further, since the element contact portion and the lead connection portion are connected via a connection portion having a bent portion below the lead frame, only the element contact portion is provided inside or inside the interposed body. Can be arranged. In other words, the lead connection portion can be drawn out of the interposer. Therefore, there is no restriction on the tip shape (the end shape opposite to the bent portion) of the lead connection portion. Therefore, a ring-shaped caulked portion is formed at the tip of the above-described lead connection portion, so that the bonding strength between the lead frame and the lead wire can be secured at a certain level or more. Resistance to a certain level or more can be secured.

Further, in such a configuration, the lead frame can be fixed to the interposer by sandwiching the interposer between the element contact portion and the lead connection portion, and the lead frame and the interposer are integrated. It can be configured as an integrated terminal unit. For this reason, at the time of electrical connection between the detection element and the lead frame (that is, the lead wire), it is only necessary to connect this terminal unit to the detection element which is fixed to the metal shell in advance. It will be easier.

If the lead frame outside the interposer is not restrained, it may come into contact with each other due to vibration or the like, or may come into contact with surrounding members. It is preferable to provide an insulating protection body outside the frame so that the connecting portion of the lead frame is accommodated inside the frame.

In this case, it is preferable that the interposition body and the insulating protection body are integrally formed as described in claim 3 because the terminal unit can be easily assembled. When the interposer and the insulating protection body are integrally formed as described above, or when the interposer for a plurality of lead frames is integrated, the interposer is formed from an insulating member. Become. On the other hand, when the interposition body and the insulating protection body are formed separately and provided for each of the plurality of lead frames, the interposition body is made of a conductive material such as a metal. can do.

By the way, also in the above configuration, in order to secure stable contact between the element contact portion and the electrode terminal,
It is preferable that means for urging the element contact portion of the lead frame toward the electrode terminal be provided. For example, as described in claim 4, it is conceivable to adopt a configuration in which the element contact portion is deformed so as to generate an elastic stress, and the element contact portion is sandwiched between the detection element and the interposed body. By doing so, the element contact portion and the electrode terminal can be stably contacted.

On the other hand, when the element contact portion itself is deformed, the contact pressure between the element contact portion and the electrode terminal becomes locally too high, and there is a possibility that the electrode terminal may be damaged. Therefore, in the sensor according to the fifth aspect, an elastic body that generates elastic stress is interposed between the interposed body and the element contact portion.

According to a sixth aspect of the present invention, a configuration is conceivable in which a spring portion connected via a second bent portion is provided at an end of the element contact portion opposite to the bent portion. Can be The spring portion extends downward in a manner to be juxtaposed with the element contact portion, and is interposed between the interposed body and the element contact portion.

According to this structure, before the terminal unit is attached to the detecting element, the biasing force of the spring to the element contacting part is reversely applied to the interposed body as a reaction force. Become. This further increases the holding force of the element contact portion and the lead connection portion on a part of the interposed body, and realizes stable fixing of the lead frame to the interposed body.

Further, since the element contact portion can be formed in a flat plate shape, the elastic stress of the elastic body is uniformly applied to the electrode terminal, so that the possibility of damaging the electrode terminal can be reduced. On the other hand, after the terminal unit is attached to the detection element, the displacement of the spring portion toward the interposition body is prevented by the interposition body, so that the biasing force of the spring part toward the detection element can be maintained. Thus, the contact between the element contact portion and the electrode terminal of the detection element can be stably maintained.

Further, according to this configuration, by providing the spring portion itself with strong elasticity, the contact pressure between the element contact portion and the electrode terminal can be increased, and more stable electrical connection can be maintained. it can. However, when the detection element is inserted into the interposer, the lead frame may be unnecessarily drawn into the interposer due to the frictional force between the element contact portion and the electrode terminal caused by the contact pressure. . Especially when this contact pressure is large, it is not only difficult to set the contact position between the element contact portion and the electrode terminal to a regular position,
The lead frame may be deformed.

Therefore, as described in claim 7, at the end of the spring portion opposite to the second bent portion, the spring portion extends toward the interposition body and is locked to the lower surface of the interposition body. It is preferable to provide a locking portion. According to such a configuration, the lower surface of the interposition body prevents the spring portion, and hence the element contact portion from moving upward, so that the element contact portion can be held at a predetermined position in the interposition body.

The interposer does not necessarily have to be provided integrally with the main body, but may be integrated with the main body when the lead frame is assembled. For example, an insulating protection body is provided between the metal shell and the detection element to hold the detection element, and is formed of a sleeve disposed so as to cover the periphery of the lead connection portion at the upper end side, But,
It may be constituted by an insulating member interposed from above between the element contact portion and the lead connection portion.

With this configuration, the detecting element can be fixed to the metal shell in advance, and the lead frame can be mounted on the detecting element from this state. This insulating member may be interposed in a state where the lead frame is mounted on the detection element in advance, or may be used as a guide when the lead frame is mounted on the detection element.

In any case, by interposing the insulating member, the element contact portion of the lead frame can be stably fixed and held to the electrode terminal of the detection element. In this case, also in this case, when the interposition body is provided for each of the plurality of lead frames, the interposition body may be made of a conductive material such as a metal.

As described above, when the interposition body and the insulating protection body are separate from each other, the connecting portion of the lead frame is deformed so as to generate an elastic stress. It may be configured to be sandwiched between insulating protection members. Particularly in this case, the interposition member functions as a wedge driven into a gap between the element contact portion and the connection portion of the lead frame inserted between the detection element and the insulating protection member. The main body to which the lead frame is fixed is an insulating protective body.

Although the expression "up and down" is used in the above description, it does not represent an absolute position, but will be reversed if the sensor is mounted upside down. For convenience of the description of the claims showing the configuration of the sensor, this is merely described.

[0029]

Preferred embodiments of the present invention will be described below with reference to the drawings. [First Embodiment] In this embodiment, the sensor of the present invention is configured as an oxygen sensor, and FIG. 1 is a cross-sectional view showing the entire configuration of the oxygen sensor.

As shown in FIG. 1, the oxygen sensor 1 comprises a flat detecting element 2 having a rectangular cross section, a casing 3 for accommodating the detecting element 2, and the like. The detection element 2 is formed by laminating a plurality of oxygen concentration cell elements formed in a long plate shape and a plurality of heaters for activating the oxygen concentration cell elements (not shown). A cylindrical support member 4 made of ceramic for locking and fixing itself within the casing 3 is inserted and adhered to the outer periphery near the center in the axial direction. At the lower end of the detecting element 2, there is provided a detecting section 2a for detecting a gas component to be measured by being exposed to the gas to be measured, and an oxygen concentration cell generated by the detecting section 2a is provided at a side face at an upper end side. A plurality (four in this embodiment) of electrode terminals 2b for extracting an electromotive force are attached.

The casing 3 fixes the oxygen sensor 1 to a mounting portion such as an exhaust pipe, and has a detection element 2 on which the support member 4 is mounted, a filling member 5 made of talc powder, and a sleeve 6 for pressing the filling member 5. Etc. are housed inside. The casing 3 is provided with a metal shell 7 for projecting the detection portion 2a of the detection element 2 into an exhaust pipe or the like, and extends above the metal shell 7 to form a predetermined internal space with the detection element 2. And an outer cylinder 8.

The metallic shell 7 has an inwardly protruding step 7a on the inner periphery of the cylindrical body at the tip end side. The support member 4 is locked to the step 7a so that the detecting element 2 can be moved from below. I support it. Further, a filling member 5 is disposed between the inner peripheral surface of the metal shell 7 and the outer peripheral surface of the detection element 2 on the rear side (upper side in the figure) of the support member 4. A cylindrical sleeve 6 is inserted coaxially.

A circular upper opening is formed at the upper end (rear end) of the metal shell 7 by the front edge of a flange 7b extending inward. Locked from above. Then, the lower end opening end of the outer cylinder 8 is covered with the metallic shell 7 so as to cover the upper opening.
The outer cylinder 8 is attached to the metal shell 7 by externally crimping the lower end opening end from outside.

A terminal unit 10 is connected to the upper end of the detection element 2. This terminal unit 10
Has four terminals (lead frame 11). Each of the lead frames 11 has one end connected to each of the four electrode terminals 2b of the detection element 2 and the other end connected to a pair of lead wires 21 and 22 for extracting a detection signal of the detection unit 2a to the outside. A pair of lead wires for supplying power to the heater (located on the back side of the lead wires 21 and 22 in the figure)
Connected to each other. Details of these structures will be described later.

A cylindrical sealing member 20 made of rubber is provided in the upper opening of the outer cylinder 8, and the axial center position of the sealing member 20 is radially caulked via the outer cylinder 8. The seal between the outer cylinder 8 and the seal member 20 is maintained. The seal member 20 is formed with a through-hole for inserting each of the lead wires, and each lead wire is drawn out through an axial through-hole provided in the seal member 20. .

A metal double protector 31, 32 having a plurality of holes and covering a protruding portion of the detecting element 2 is attached to the outer periphery of the distal end side (lower side in the figure) of the metal shell 7 by welding. Have been. Next, a detailed structure around the terminal unit 10, which is a main part of the oxygen sensor 1, and a method of assembling the same to the detection element 2 will be described with reference to FIGS.

As shown in an exploded view of the terminal unit 10 in FIG. 2, the terminal unit 10 has four lead frames 11 connected to each of the four electrode terminals 2b of the detecting element 2.
And an insulating separator sleeve 12 for fixing the lead frame 11.

The lead frame 11 is formed, for example, by bending a long thin stainless steel plate or a corrosion-resistant heat-resistant superalloy plate capable of retaining elasticity (spring elasticity) even when repeatedly exposed to a high temperature at several places. , As shown in the lower part of FIG.
A lead connection portion 13 connected to each lead wire, an element contact portion 15 that contacts the electrode terminal 2b of the detection element 2, and a spring portion 17 are provided.

The lead connection part 13 and the element contact part 15
The element contact portion 15 and the spring portion 17 are connected to each other via a bent portion 11 a formed at a lower portion of the lead frame 11, and are connected to the second bent portion 1 connected to the upper end of the element contact portion 15.
1b. The lead connection part 13 and the element contact part 15 are arranged side by side substantially in parallel, and the spring part 17 is provided between the lead connection part 13 and the element contact part 15.
It extends downward along the element contact portion 15.

The spring portion 17 has a wavy shape and is formed so as to come into contact with the element contact portion 15 at several apexes of the wavy portion. A locking portion 17 a to be locked extends perpendicularly to the element contact portion 15 and in the direction of the lead connection portion 13.

Further, the lead connection portion 13 is bent toward the element contact portion 15 by a predetermined amount in the vicinity of the second bent portion 11b,
At its tip, a cylindrical crimping portion 13a crimped to the lead wire is provided in parallel with the element contact portion 15. On the other hand, the separator sleeve 12 has a columnar main body made of insulating ceramic. FIG. 2A shows an axial sectional view of the upper part, and FIG.
-A cross section is shown.

More specifically, the separator sleeve 12
Has an outer wall along the shape of the lead connection portion 13,
It is formed symmetrically in FIG. Also,
A pair of partitioning portions 12a extending outward by a predetermined amount along the outer shape are formed at the center in the depth direction of FIG. In the center of the main body, a housing part 1 opened downward is provided.
4 is formed at a position corresponding to the partition portion 12a of the storage portion 14 and a partition portion 14a extending inward by a predetermined amount.
Are formed. Further, in the center of the lower surface of the main body, a flat base portion 16 mounted on the upper surface of the sleeve 6 is provided.
Extends downward.

Then, as shown by the arrows, by assembling the four lead frames 11 from below the separator sleeve 12, the terminal unit 10 shown in the upper part of FIG. 3A is completed. In this embodiment, the width W1 of the housing portion 14 is 3.7 ± 0.1 (mm), and the thickness of the lead frame 11 (that is, the distance between the outer vertex of the spring portion 17 and the element contact portion 15) t1 is 1.25 ± 0.1 (m
m), the thickness T1 of the detection element 2 is 2.0 ± 0.2 (mm)
The fitting allowance (press-fit allowance) is 0.8 ± 0.5
(Mm).

Therefore, the spring portion 1 of the lead frame 11
The biasing force applied to the element contact portion 15 by the element 7 acts as a reaction force and is applied to the inner wall of the separator sleeve 12. By this action, the lead connection portion 13 is strongly adhered along the outer wall of the separator sleeve 12, and the lead frame 11 is stably fixed to the separator sleeve 12.

FIG. 4B shows a cross section taken along the line BB of FIG.
Are separated from each other by the partitions 12a, 14a or the space in the left-right direction, and the short circuit is prevented. And
As shown by an arrow in FIG.
0 to the detection element 2 previously fixed to the sleeve 6 (that is, to the metal shell 7) from above,
Each lead wire is electrically connected to the detection element 2.

This state is shown in FIG. FIG. 2B shows a C-C section thereof. At this time, the terminal unit 10 is fixed at a fixed position with respect to the detection element 2 by mounting the base portion 16 on the upper surface of the sleeve 6. In addition, the lead frame 11 is
7a is locked to the lower surface of the separator sleeve 12, so that the position thereof does not shift when connected to the detecting element 2. Therefore, the element contact portion 15 is also fixed at a fixed position in contact with the electrode terminal 2b.

Also, since the inner wall of the separator sleeve 12 prevents the spring portion 17 from being displaced outward,
The urging force of the spring portion 17 toward the detection element 2 can be maintained at a certain level or more, and a stable contact state between the element contact portion 15 and the electrode terminal 2b can be maintained.

As described above, in the oxygen sensor 1 of the present embodiment, the attachment of the detection element 2 to the metal shell 7 and the electrical connection of the lead frame 11 to the detection element 2 are performed in separate steps. Therefore, the detection element 2 can be accurately attached to a predetermined position of the metal shell 7. as a result,
The characteristics of the sensor can be kept constant without the problem that the protrusion dimensions of the detection section 2a of the detection element 2 vary.

Further, since the lead frame 11 is configured as the terminal unit 10 integrated with the separator sleeve 12, the lead frame 11 can be mounted on the detecting element 2 with one touch, and the mounting becomes extremely easy. . As a result, workability is improved. [Second Embodiment] The oxygen sensor of the present embodiment does not have the structure of the terminal unit as described in the first embodiment. Is fixed.

FIG. 5 shows an oxygen sensor 201 according to this embodiment.
3 is a cross-sectional view illustrating a configuration around a main part of FIG. Since the oxygen sensor 201 has the same configuration as the oxygen sensor 1 of the first embodiment except for the configuration of the main part, the same components as those of the first embodiment are denoted by the same reference numerals, or The description will be omitted, and the description thereof will be omitted.

As shown in the figure, the sleeve 206 of the oxygen sensor 201 has a different shape from that of the sleeve 6 of the first embodiment, and has a projecting portion 207 projecting upward at the upper center of the cylindrical main body. Having. The detecting element 2 and the lead frame 211 are connected and fixed via an insulating member 220 in a housing portion 208 formed inside the projecting portion 207.

The detailed structure of the main part of the oxygen sensor 201 and the method of assembling it to the detecting element 2 will be described below with reference to FIGS.
It will be described based on. FIG. 6 shows a detailed structure of a main part of the sleeve 6 and an assembling mode of the detecting element 2.

The sleeve 206 is formed of an insulating ceramic, and as shown in the figure, at the center of the protruding portion 207, the housing portion 208 communicating with the insertion hole 206a of the lower detecting element 2 is formed. I have. This storage unit 208
It has a larger angular cross section than the insertion hole 206a, and is smoothly connected to the insertion hole 206a via the inclined portion 209. In addition, the axial length (depth) of the housing portion 208
Is longer than the length of the electrode terminal 2b of the detection element 2.

FIG. 4B is a sectional view taken along the line DD of FIG.
As shown in the cross-sectional view, a pair of partitioning portions 20 projecting inward by a predetermined amount are provided in the center of the accommodation portion 208 in the depth direction.
8a are formed. The detection element 2 is
06, it is fixed in advance at a position where the upper end face of the projection 207 coincides with the upper end face of the projection 207 (in this embodiment, the height of the projection 207 is defined as such).

Then, as shown in FIG. 7A, from this state, each of the four lead frames 211
08 from above. The lead frame 211 is
An element contact portion which is formed by bending a long thin plate-like stainless steel similar to that of the first embodiment and which is connected to each lead wire, and which contacts the electrode terminal 2b of the detection element 2. 215. However, unlike the first embodiment, the lead connection part 213 also serves as the spring part 213a.

The lead connection part 213 and the element contact part 215 are connected to the bent part 2 formed below the lead frame 211.
They are connected to each other via 11a. This bent part 21
1a has an inclined portion along the inclined portion 209. The lead connection part 213 and the element contact part 215 are arranged side by side substantially in parallel, and the wavy part of the spring part 213a is formed so as to contact the inner wall of the housing part 208 at several points at its apex.

Further, at the upper end of the lead connection portion 213,
A cylindrical caulking portion 213b to be caulked to the lead wire is provided. As shown in FIG. 2B, a cross section taken along line EE of FIG. 2A prevents the short circuit between the lead frames 211 arranged adjacent in the depth direction by the partitioning portion 208a.

Then, as shown in FIG. 8A, a pair of insulating members 220 are connected to the element contact portion 215 and the spring portion 213a.
(That is, the lead connection portion 213).
The insulating member 220 is made of a plate-like small piece made of insulating ceramic, has a length substantially equal to the depth of the housing portion 208, a width slightly smaller than the width of the housing portion 208 in the depth direction in the drawing, and It has a thickness that is larger by a predetermined amount than the distance between the apex inside the spring part 213a and the element contact part 215. In addition, a tapered portion 220a is formed outside the lower portion of the insulating member 220 in consideration of insertability.

Specifically, in this embodiment, FIG.
As shown in FIG. 8A and FIG. 8A, the width W2 of the housing portion 208 is 5.9 ± 0.1 (mm), and the press-fit width of the lead frame 11 (that is, the vertex inside the spring portion 213a and the element Distance t2 between contact part 215) is 0.6 ± 0.1 (mm),
The thickness t3 of the insulating member 220 is 1.0 ± 0.1 (m
m), the thickness T1 of the detection element 2 is 2.0 ± 0.2 (mm)
It has become.

Therefore, when these insulating members 220 are interposed, the space between the spring portion 213a and the element contact portion 215 is pushed and expanded, and the shape of the spring portion 213a is deformed by a predetermined amount. At this time, the biasing force of the spring portion 213a of the lead frame 211 is transmitted to the element contact portion 215 via the insulating member 220, and by this action, the element contact portion 215 comes into close contact with the electrode terminal 2b, and the stable contact is made. Is achieved.

As shown in FIG. 7B, which is a cross-sectional view taken along line FF of FIG. 8A, the insulating member 220 is formed of two lead frames 211 and two electrode terminals 2b adjacent in the depth direction in the figure. Although it looks like cross-linking, there is no fear of short-circuiting because the insulating member 220 has insulating properties.

The oxygen sensor 201 of the present embodiment described above
Also in the configuration of FIG.
Independent of the sleeve 206 (that is, the metal shell 7)
The lead frame 211 can be attached to the detection element 2 in this state.

Therefore, similarly to the first embodiment, the detecting element 2
Can be accurately attached to a predetermined position of the metal shell 7. Further, since the fixing between the lead frame 211 and the detecting element 2 is performed by a simple and simple method of interposing the insulating member 220, the assembling becomes extremely easy.

The embodiments of the present invention have been described above. However, the embodiments of the present invention are not limited to the above-described embodiments, and may take various forms within the technical scope of the present invention. Needless to say. For example, the second
In the embodiment, the insulating member 220 is interposed in a state where the lead frame 211 is mounted on the detection element 2. However, when the lead frame 211 is mounted on the detection element 2, the insulating member 220 is It may be used as the guide.

[Brief description of the drawings]

FIG. 1 is a sectional view illustrating an overall configuration of an oxygen sensor according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram illustrating a configuration of a terminal unit according to the first embodiment.

FIG. 3 is an explanatory diagram showing a configuration of a terminal unit of the first embodiment and an assembling mode thereof.

FIG. 4 is an explanatory diagram showing a manner of assembling the terminal unit of the first embodiment to a detection element.

FIG. 5 is a cross-sectional view illustrating a configuration of a main part of an oxygen sensor according to a second embodiment.

FIG. 6 is an explanatory diagram showing an assembling mode of a main part of the oxygen sensor according to the second embodiment.

FIG. 7 is an explanatory diagram showing an assembling mode of a main part of the oxygen sensor according to the second embodiment.

FIG. 8 is an explanatory diagram showing an assembling mode of a main part of the oxygen sensor according to the second embodiment.

FIG. 9 is a cross-sectional view illustrating an entire configuration of a conventional oxygen sensor.

[Explanation of symbols]

1,201 ... oxygen sensor, 2 ... detection element,
2a: detection unit, 2b: electrode terminal, 6,206
... Sleeve, 7 ... Metal shell, 10 ... Terminal unit, 11, 211 ... Lead frame, 11
a, 211a: bent portion, 11b: second bent portion, 13a, 213b: caulked portion, 12: separator sleeve, 13, 213: lead connection portion,
15, 215 ... element contact portion, 17, 213a ...
Spring part, 17a: locking part, 220: insulating member

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2G004 BB04 BC02 BD04 BF18 BF27 BG05 BH04 BH09 BJ03 BJ05

Claims (8)

[Claims] 1. A flat detection element having a detection portion on a lower end side, and a plurality of electrode terminals formed on a side surface on an upper end side for extracting a detection signal of the detection portion to the outside; A lead frame having an element contact portion that comes into contact with the lead wire and the electrode terminal to be drawn out, a lead connection portion connected to the lead wire, and a connection portion that connects the element contact portion and the lead connection portion. Wherein the connecting portion has a bent portion at a lower portion of the lead frame, and the connecting portion connects to the element contact portion via the bent portion and the element contact. A sensor comprising an interposed body interposed between the sensor and a part. 2. An insulating protection body disposed so as to cover a periphery of an upper end of the detection element on a side where the electrode terminal is formed, wherein the lead frame is fixed between the insulation protection body and the detection element. The sensor according to claim 1, wherein: 3. The sensor according to claim 1, wherein the interposition body and the insulating protection body are integrated. 4. The element contact portion is deformed so as to generate an elastic stress.
The sensor according to claim 1, wherein the element contact portion is fixed between the interposition body and the electrode terminal. 5. The device according to claim 1, wherein the element contact portion has a plate shape, and an elastic body that generates elastic stress is interposed between the interposed body and the element contact portion. 3. The sensor according to 3. 6. The lead frame has a second bent portion at an end opposite to the bent portion with the element contact portion interposed therebetween, and extends downward from the second bent portion. The sensor according to claim 5, wherein an extending portion is formed, and the extending portion forms the elastic body. 7. A locking portion is provided at an end of the extension portion opposite to the second bent portion, the locking portion extending toward the interposition body and being locked to a lower surface of the interposition body. 7. The sensor according to claim 6, wherein: 8. A connecting portion between the interposition body and the insulating protection body is deformed so as to generate an elastic stress, and the lead frame is moved by the elastic stress of the connecting portion between the insulating protection body and the detecting element. The sensor according to claim 2, wherein the sensor is fixed between the sensors.