JP2016050835A - Gas sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas sensor that has a squeeze rate for a sealant with reduced variations and a smaller size in a longitudinal direction of the gas sensor.SOLUTION: The gas sensor includes a plurality of lead wires 3, covers 2A and 2B, and a plurality of sealants 4. The lead wires 3 are connected to electrodes of a sensor element, respectively, and are drawn in a longitudinal direction L of the sensor element. The covers 2A and 2B cover the connection parts of the lead wires 3. The sealants 4 are made of rubber and form an annular shape around a center axis line O along the longitudinal direction L, and are respectively installed on the lead wires 3. The covers 2A and 2B compress the sealants 4 from the inside 401 and the outside 402 of the longitudinal direction L of the sealants 4 until an internal circumference 404 of each sealant 4 in a radial direction R becomes in close contact with the lead wire 3.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a gas sensor having a lead wire holding structure.

In the gas sensor, a lead wire for connecting an electrode provided in the sensor element to the outside of the gas sensor is provided. Further, the lead wire is inserted into the hole provided in the holding member, and the lead wire is fixed by compressing the holding member from the outer periphery by the cover of the gas sensor.
Further, for example, in a sensor having a ventilation structure disclosed in Patent Document 1, a taper-shaped lead wire insertion hole having an inner diameter that increases toward the inside of the sensor is formed in the holding member. A lead wire is inserted through a conical seal ring. And the holding member is fixed in the outer cylinder, and the airtightness and watertightness around the lead wire are secured by the seal ring.

JP 2002-286585 A

  However, the seal ring is pressed from only one direction by the tapered lead wire insertion hole, and cannot move in the downward direction of the seal ring (the inner direction from which the lead wire is drawn out). Variation in the crushing ratio (compression ratio) as a ratio of crushing tends to occur. Further, in the longitudinal direction, which is the direction in which the lead wire extends, the length occupied by the holding member is large, and it is difficult to reduce the size of the gas sensor in the longitudinal direction.

  The present invention has been made in view of such a background, and has been obtained in an attempt to provide a gas sensor that can suppress variation in the crushing rate of the sealing material and can be downsized in the longitudinal direction of the gas sensor.

In one embodiment of the present invention, a plurality of lead wires respectively connected to a plurality of electrodes of the sensor element and led out in a longitudinal direction of the sensor element;
A cover for covering the connecting portions of the plurality of lead wires;
A plurality of rubber sealing materials that are respectively sheathed on the plurality of lead wires and have a ring shape around the central axis along the longitudinal direction,
The cover includes an inner side in the longitudinal direction of the sealing material, an outer side in the longitudinal direction of the sealing material, an outer peripheral side in a radial direction of the sealing material, and an inclination direction of the outer side and the outer peripheral side of the sealing material. The gas sensor is characterized in that the sealing material is compressed from any one of the two directions, and the radially inner peripheral side of the sealing material is brought into close contact with the lead wire.

In the gas sensor, depending on the cover, any one of the inner side in the longitudinal direction of the sealing material, the outer side in the longitudinal direction of the sealing material, the outer peripheral side in the radial direction of the sealing material, and the outer and outer peripheral sides in the inclined state of the sealing material. The sealing material is compressed from the direction, and the inner peripheral side in the radial direction of the sealing material is brought into close contact with the lead wire. The cover compresses the sealing material from two directions, so that the amount of crushing the sealing material by the cover can be easily maintained, and variation in the crushing rate (compression rate) of the sealing material can be reduced. .
The inclination direction on the outer side and the outer peripheral side of the sealing material is an inclination direction in which the cover can compress the sealing material simultaneously from both the outer side in the longitudinal direction of the sealing material and the outer peripheral side in the radial direction of the sealing material. That means.

  In general, when the heat resistance of the sealing material is improved, its crack resistance tends to deteriorate. In this regard, in the gas sensor described above, the sealing material can be used at an appropriate crushing rate by adopting a structure in which a rubber sealing material is packaged and compressed for each lead wire. Thereby, the rubber material excellent in crack resistance can be used for the sealing material, and the heat resistance of the sealing material can be improved.

In the gas sensor, the sealing material can be directly pressed by the cover. Then, without using a holding member or the like between the cover and the sealing material, the inside and outside of the gas sensor can be sealed (sealed) around the lead wire to hold the lead wire on the gas sensor. . Thereby, the length which the sealing material holding a lead wire occupies in the longitudinal direction of the gas sensor can be reduced, and downsizing in the longitudinal direction of the gas sensor can be achieved.
Therefore, according to the gas sensor, variation in the crushing rate of the sealing material can be suppressed, and the gas sensor can be downsized in the longitudinal direction.

Sectional explanatory drawing which shows the gas sensor concerning Example 1. FIG. Sectional explanatory drawing which expands and shows the principal part of the gas sensor concerning Example 1. FIG. FIG. 2 is a diagram illustrating the gas sensor according to the first embodiment and is a cross-sectional view taken along the line II in FIG. 1. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory view showing a state in which each electrode spring is in contact with each electrode in a sensor element according to Example 1 in a cross section orthogonal to the longitudinal direction of the sensor element. Sectional explanatory drawing which shows the gas sensor concerning Example 2. FIG. Sectional explanatory drawing which expands and shows the principal part of the gas sensor concerning Example 2. FIG. FIG. 5 is a cross-sectional view taken along line II-II in FIG. Cross-sectional explanatory drawing which expands and shows the principal part of the other gas sensor concerning Example 2. FIG. Sectional explanatory drawing which expands and shows the principal part of the gas sensor concerning Example 3. FIG.

A preferred embodiment of the gas sensor described above will be described.
In the gas sensor, the cover includes a first cover that presses the entire inner circumference in the longitudinal direction of the sealing material, and an entire outer surface in the longitudinal direction of the sealing material that overlaps the first cover from the outside. A second cover that presses the periphery, and the seal material can expand to the outer peripheral side in the radial direction at a position adjacent to the entire outer periphery of the seal material in the radial direction. A seal space may be formed surrounded by the first cover and the second cover.
With the above configuration, the entire circumference of each sealing material can be compressed in the longitudinal direction by the first cover and the second cover, and variations in the crushing rate of each sealing material can be easily reduced. Further, the sealing material can be expanded using the sealing space, and the crushing rate of the sealing material can be set more appropriately.

In addition, the cover includes a first cover that presses the entire inner periphery of the seal material in the longitudinal direction and an outer periphery of the seal material, and overlaps the first cover from the outside in the radial direction of the seal material. A second cover that presses the outer peripheral side, and at a position adjacent to the other of the inside and outside in the longitudinal direction of the seal material, a seal space in which the seal material can expand is the first cover. It may be formed surrounded by one cover and the second cover.
With the configuration described above, the outer peripheral side of each sealing material can be compressed to the inner peripheral side by the first cover and the second cover, and variation in the crushing rate of each sealing material can be easily reduced. Further, the sealing material can be expanded using the sealing space, and the crushing rate of the sealing material can be set more appropriately.

The cover is inclined so that the first cover presses the entire inner circumference in the longitudinal direction of the sealing material, and the first cover overlaps with the first cover from the outside and is narrowed toward the outside in the longitudinal direction. And a second cover that presses the entire circumference of the sealing material in the inclined direction by an inclined surface, and the seal material is positioned at a position adjacent to the entire circumference on the outer peripheral side in the radial direction of the sealing material. A seal space in which the material can expand to the outer peripheral side in the radial direction may be formed surrounded by the first cover and the second cover.
With the above configuration, the entire circumference of each sealing material can be compressed in the longitudinal direction and the radial direction by the first cover and the second cover, and variations in the crushing rate of each sealing material can be easily reduced. Further, the sealing material can be expanded using the sealing space, and the crushing rate of the sealing material can be set more appropriately.

Below, the example concerning a gas sensor is described with reference to drawings.
(Example 1)
As shown in FIGS. 1 to 3, the gas sensor 1 includes a plurality of lead wires 3, covers 2 </ b> A and 2 </ b> B, and a plurality of sealing materials 4. The plurality of lead wires 3 are connected to the plurality of electrodes 51 </ b> A and 51 </ b> B of the sensor element 5, respectively, and are drawn out in the longitudinal direction L of the sensor element 5. The covers 2 </ b> A and 2 </ b> B are configured to cover the connection portions 33 of the plurality of lead wires 3. The plurality of sealing materials 4 have a ring shape around the central axis O along the longitudinal direction L, are made of rubber, and are respectively covered with the plurality of lead wires 3. Covers 2 </ b> A and 2 </ b> B have a structure for holding the lead wire 3, compressing the sealing material 4 from the two directions of the inner side 401 and the outer side 402 of the sealing material 4, and the inner circumference of the sealing material 4 in the radial direction R The side 404 is in close contact with the lead wire 3.

Hereinafter, the gas sensor 1 of this example will be described in detail with reference to FIGS.
As shown in FIG. 1, the gas sensor 1 of this example is disposed in an exhaust pipe of an internal combustion engine, and is used for measuring the concentration of a specific gas in the exhaust gas flowing in the exhaust pipe. The gas sensor 1 includes a sensor element 5, and the sensor element 5 includes a plate-shaped solid electrolyte body having oxygen ion conductivity, and an insulator and a heater stacked on the solid electrolyte body. The sensor element 5 of this example is a laminated type, and is configured by laminating a plate-shaped solid electrolyte body with a plate-shaped insulator and a plate-shaped ceramic heater. A measured gas space into which a measured gas (exhaust gas) is introduced is formed between one surface of the solid electrolyte body and the insulator, and is formed between the other surface of the solid electrolyte body and the heater. The reference gas space into which the reference gas is introduced is formed. The sensor element 5 includes a gas to be measured (exhaust gas) in contact with the electrode 51A provided on one surface of the solid electrolyte body and a reference gas (atmosphere) in contact with the electrode 51A provided on the other surface of the solid electrolyte body. ) And the oxygen concentration difference. In FIG. 1, the electrodes 51A and 51B are schematically shown.

As shown in FIG. 3, a total of four lead wires 3 are arranged on a virtual circle C around the central axis of the covers 2A and 2B. Each lead wire 3 is connected to the electrode 51 via an electrode spring 61 that contacts the electrode 51 in an elastically deformed state. The lead wire 3 includes a conductor layer 31 located on the center side and an insulating coating layer 32 that covers the periphery of the conductor layer 31.
As shown in FIG. 1, the conductor layer 31 at the end of the lead wire 3 and the end of the electrode spring 61 are connected by a metal fitting as the connecting portion 33. The electrode 51 in the sensor element 5 is extended from the distal end side portion in the longitudinal direction L of the sensor element 5 to the proximal end side portion. The front end portion of the sensor element 5 is disposed so as to protrude into the exhaust pipe through which the gas to be measured flows. The electrode spring 61 is in contact with the electrode 51 at the proximal end portion of the sensor element 5 while being held on the inner peripheral side of the insulator 62.

  As shown in FIG. 4, the electrodes 51 </ b> A and 51 </ b> B in the sensor element 5 are disposed inside a pair of sensor electrodes 51 </ b> A drawn from the surface of the solid electrolyte body to the proximal end side in the longitudinal direction L, and the heater. There is a pair of heater electrodes 51B drawn from the heating element. The sensor electrode 51 </ b> A is provided at a position on the distal end side in the longitudinal direction L of the solid electrolyte body and is connected to an electrode measurement unit that is in contact with a measurement gas or a reference gas. The heater electrode 51B is connected to a heater heating element disposed at a position facing the electrode measuring section.

The pair of sensor electrodes 51 </ b> A are arranged on one surface of the sensor element 5 in a direction orthogonal to the longitudinal direction L, and the pair of heater electrodes 51 </ b> B are disposed on the other surface of the sensor element 5. These are arranged side by side in a direction orthogonal to the longitudinal direction L.
An electrode spring 61 and a lead wire 3 are connected to the pair of sensor electrodes 51A and the pair of heater electrodes 51B, respectively. The pair of sensor electrodes 51A can be used as electrodes for measuring oxygen concentration, measuring A / F (air-fuel ratio), measuring specific gas concentration, and the like. Two or more pairs of sensor electrodes 51A may be provided in accordance with the application.
The number of electrodes provided on the sensor element 5 can be an even number such as 2, 4, 6, 8, etc., depending on the specifications of the sensor element 5, and can be 3, 5, or 7. Or an odd number such as

As shown in FIG. 2, the covers 2 </ b> A and 2 </ b> B are provided between the first cover 2 </ b> A and the first cover 2 </ b> A attached to a housing that covers the connecting portion 33 of the lead wire 3 and holds the insulator 62 from the outer peripheral side. The second cover 2B overlaps the first cover 2A from the outside so as to sandwich the plurality of sealing materials 4. A plurality of (four in this example) lead wires 3 are provided on the base end portions 21A and 21B as the outer portions in the longitudinal direction L of the first cover 2A and the second cover 2B at positions overlapping with each other in the longitudinal direction L. An insertion hole 211 is formed for inserting the.
1st cover 2A and 2nd cover 2B are formed in the cup shape by base end side part 21A, 21B and outer peripheral side part 22A, 22B.

The proximal end portion 21A of the first cover 2A simultaneously contacts the inner side 401 in the longitudinal direction L of the plurality of sealing materials 4, and the proximal end portion 21B of the second cover 2B is in the longitudinal direction L of the plurality of sealing materials 4. Simultaneously touch the outside 402 of the. The plurality of sealing materials 4 are pressed on the entire circumference of the inner side 401 in the longitudinal direction L by the proximal end portion 21A of the first cover 2A, and the outer side 402 of the longitudinal direction L by the proximal end portion 21B of the second cover 2B. Is pressed all around.
Further, at a position adjacent to the entire circumference of the outer peripheral side 403 in the radial direction R of the sealing material 4, a seal space K1 in which the sealing material 4 can expand to the outer peripheral side 403 in the radial direction R is the first cover 2A and It is formed surrounded by the second cover 2B. The seal space K1 of this example is a space portion in which the plurality of lead wires 3 and the seal material 4 are not disposed between the proximal end portion 21A of the first cover 2A and the proximal end portion 21B of the second cover 2B. It is formed as. The sealing space K1 is formed in anticipation of the volume that expands when the sealing material 4 is heated to 300 ° C.

As shown in FIG. 1, the outer peripheral side portion 22B of the second cover 2B is in close contact with the outer periphery of the outer peripheral side portion 22A of the first cover 2A. At this time, the outer peripheral portion 22B of the second cover 2B can be fitted or press-fitted into the outer peripheral portion 22A of the first cover 2A, and can also be crimped to the outer peripheral portion 22A of the first cover 2A. . When the outer peripheral side portion 22B of the second cover 2B is fitted or press-fitted into the outer peripheral side portion 22A of the first cover 2A, the base end side portion 21A of the first cover 2A and the base end of the second cover 2B The interval W with the side portion 21B is fixed, and the crushing rate of each sealing material 4 is kept substantially constant.
When assembling the periphery of the lead wire 3, each lead wire 3 is inserted into each insertion hole 211 of the first cover 2A. Next, the sealing material 4 is sheathed on each lead wire 3 drawn from the first cover 2A. Thereafter, the first cover 2A holding the lead wires 3 and the sealing materials 4 and the second cover 2B are assembled, and all the sealing materials 4 are sandwiched between the first cover 2A and the second cover 2B. .

  The sealing material 4 of this example is an O-ring whose circular cross section is connected in an annular shape, and is attached to the outer periphery of the lead wire 3. The O-ring is made of fluoro rubber (FKM). Each sealing material 4 is sandwiched between a first cover 2A located on the inner side (front end side) 401 in the longitudinal direction L and a second cover 2B located on the outer side (base end side) 402 in the longitudinal direction L. Compressed in the longitudinal direction L. In the cross-section of the sealing material 4, the seal when the thickness (wire diameter) in the direction along the central axis O in the natural state is D (mm) and the crushing allowance in the direction along the central axis O is δ (mm) The crushing ratio δ / D × 100 (%) of the material 4 is set to 20 to 40%. When the crushing rate is less than 20%, there is a possibility that sufficient sealing performance around the lead wire 3 cannot be obtained. On the other hand, if the crushing rate exceeds 40%, the sealing material 4 may break.

  In the gas sensor 1 of the present example, the first cover 2A and the second cover 2B compress the sealing material 4 from the two directions of the inner side 401 and the outer side 402 in the longitudinal direction L of the sealing material 4, and the radial direction of the sealing material 4 The inner peripheral side 404 of R is brought into close contact with the lead wire 3. Then, the first cover 2A and the second cover 2B compress the sealing material 4 from two directions, so that it becomes easy to keep the amount of crushing the sealing material 4 constant. ) Can be reduced.

  Moreover, generally, when the heat resistance of the sealing material 4 is improved, the crack resistance tends to deteriorate. In this regard, in the gas sensor 1, the sealing material 4 can be used at an appropriate crushing rate by adopting a structure in which the rubber sealing material 4 is packaged and compressed for each lead wire 3. Thereby, the rubber material excellent in crack resistance can be used for the sealing material 4, and the heat resistance of the sealing material 4 can be improved.

Further, in the gas sensor 1, the sealing material 4 can be directly pressed by the first cover 2A and the second cover 2B. Then, without using a holding member or the like between the first cover 2 </ b> A and the second cover 2 </ b> B and the sealing material 4, sealing (sealing) between the inside and the outside of the gas sensor 1 around the lead wire 3 is performed. The lead wire 3 can be held by the gas sensor 1.
When the lead wire 3 is held by the gas sensor by caulking the cover using a holding member or the like, it is necessary to ensure the length in the longitudinal direction L for caulking. Therefore, it is difficult to reduce the length of the gas sensor in the longitudinal direction L to a certain length or less. On the other hand, in the gas sensor 1 of this example, the structure which compresses the sealing material 4 comprised from an O-ring etc. is employ | adopted. Therefore, the length of the sealing material 4 holding the lead wire 3 in the longitudinal direction L of the gas sensor 1 can be reduced, and the gas sensor 1 can be downsized in the longitudinal direction L.
Therefore, according to the gas sensor 1 of this example, variation in the crushing rate of the sealing material 4 can be suppressed, and the gas sensor 1 can be downsized in the longitudinal direction L.

Further, each sealing material 4 contacts the first cover 2A and the second cover 2B on the entire circumference of the ring shape. Thereby, a high surface pressure can be applied to each sealing material 4, and the sealing performance around the lead wire 3 by each sealing material 4 can be easily ensured.
Further, in the gas sensor 1 of this example, the step of deforming the first cover 2A and the second cover 2B in order to caulk the holding member or the like can be omitted.
Further, a sufficient seal space K1 is formed at a place where the seal material 4 is disposed. Thereby, even when the gas sensor 1 becomes high temperature and the sealing material 4 expands, the sealing performance around the lead wire 3 by the sealing material 4 can be ensured.

(Example 2)
In this example, as shown in FIG. 5 to FIG. A case where the inner peripheral side 404 in the radial direction R of the sealing material 4 is brought into close contact with the lead wire 3 is shown.
As shown in FIG. 5, the covers 2A and 2B of this example are overlapped with the first cover 2A that presses the entire circumference of the inner side 401 in the longitudinal direction L of the seal material 4 and the first cover 2A from the outside. 4 and the second cover 2B that presses the outer peripheral side 403 in the radial direction R. The first cover 2A has the same shape as the first cover 2A of the first embodiment. The second cover 2B of this example includes a pressing portion 23 for pressing each sealing material 4 from the outer peripheral side 403 in the radial direction R inside the proximal end portion 21B. The pressing portion 23 is formed around the holding recess 24 by forming a holding recess 24 that holds the sealing material 4 in the second cover 2B.

As shown in FIG. 6, at a position adjacent to the outer side 402 in the longitudinal direction L of the sealing material 4, a sealing space K <b> 2 in which the sealing material 4 can expand to the outer side 402 in the longitudinal direction L is formed with the first cover 2 </ b> A. It is surrounded by the second cover 2B. The seal space K2 is formed as a space portion between the proximal end portion 21A of the first cover 2A and the proximal end portion 21B of the second cover 2B in which the plurality of lead wires 3 and the sealing material 4 are not disposed. ing.
When assembling the periphery of the lead wire 3, each lead wire 3 is inserted into each insertion hole 211 of the first cover 2A. Further, each sealing material 4 is held in the holding recess 24 of the second cover 2B. Thereafter, the lead wires 3 in the first cover 2A are press-fitted into the inner peripheral holes of the seal members 4 in the second cover 2B, and the first cover 2A and the second cover 2B are assembled together. All the sealing materials 4 are crushed by the 2 cover 2B.

As shown in FIG. 7, the pressing portion 23 of this example has a structure that presses the entire circumference of the outer peripheral side 403 in the radial direction R of each sealing material 4.
In addition to this, the pressing portion 23 may be configured to partially press each portion in the circumferential direction of each sealing material 4 in order to reduce the weight of the second cover 2B. The pressing portion 23 includes a center-side pressing portion formed on the center side of the arrangement of the plurality of lead wires 3 and the sealing material 4 arranged on the virtual circle C, and an outer periphery of the arrangement of the plurality of lead wires 3 and the sealing material 4. It can also be comprised by the outer peripheral side press part formed in the side. In this case, the center side pressing portion presses the center side portion on the outer peripheral side 403 in the radial direction R of each sealing material 4, and the outer peripheral side pressing portion is the outer periphery on the outer peripheral side 403 in the radial direction R of each sealing material 4. The side portion is configured to be pressed.

  In the gas sensor 1 of this example, the first cover 2A and the second cover 2B compress the sealing material 4 from the two directions of the inner side 401 in the longitudinal direction L of the sealing material 4 and the outer peripheral side 403 in the radial direction R. It becomes easy to keep the amount of crushing the sealing material 4 constant, and variation in the crushing rate (compression rate) of the sealing material 4 can be reduced.

Further, instead of adopting a structure in which the first cover 2A presses the entire circumference of the inner side 401 in the longitudinal direction L of the sealing material 4, the second cover 2B is arranged in the longitudinal direction L of the sealing material 4 as shown in FIG. A structure in which the entire circumference of the outer side 402 is pressed may be employed. In this case, the seal space K2 is formed by being surrounded by the first cover 2A and the second cover 2B at a position adjacent to the inner side 401 of the seal material 4 in the longitudinal direction L. Further, a cover in which the first cover 2A and the second cover 2B are integrated is adopted, and by this cover, the entire circumference of the outer side 402 in the longitudinal direction L of the sealing material 4 and the outer peripheral side in the radial direction R of the sealing material 4 The entire circumference of 403 can also be pressed. In these cases, the same effects as described above can be obtained.
Also in this example, other configurations and reference numerals in the other drawings are the same as those in the first embodiment, and the same operational effects as those in the first embodiment can be obtained.

(Example 3)
In this example, as shown in FIG. 9, the second cover 2 </ b> B is formed on the outer side 402 and the outer side 403 of the sealing material 4 by the inclined portion 25 that is inclined so that the inner diameter is reduced toward the outer side in the longitudinal direction L. The case where the whole periphery of the inclination direction 405 is pressed is shown.
The inclined portion 25 is formed by projecting the periphery of each insertion hole 211 through which the lead wire 3 is inserted in the second cover 2B so as to swell outward in the longitudinal direction L in a triangular pyramid shape. The inclination direction 405 of the outer side 402 and the outer peripheral side 403 of the sealing material 4 is that the inclined portion 25 of the second cover 2B is connected to the outer side 402 of the sealing material 4 in the longitudinal direction L and the outer peripheral side 403 of the sealing material 4 in the radial direction R. It refers to an inclination direction in which the sealing material 4 can be compressed simultaneously from both sides. Other shapes of the second cover 2B and the shape of the first cover 2A are the same as those in the first embodiment.

Further, at a position adjacent to the outer peripheral side 403 in the radial direction R of the sealing material 4, a seal space K3 in which the sealing material 4 can expand to the outer peripheral side 403 in the radial direction R is the first cover 2A and the second cover. And 2B.
When assembling the periphery of the lead wire 3, each lead wire 3 is inserted into each insertion hole 211 of the first cover 2A. Next, the sealing material 4 is sheathed on each lead wire 3 drawn from the first cover 2A. Thereafter, the first cover 2A holding the lead wires 3 and the sealing materials 4 and the second cover 2B are assembled, and all the sealing materials 4 are sandwiched between the first cover 2A and the second cover 2B. .

In the gas sensor 1 of this example, the first cover 2 </ b> A and the second cover 2 </ b> B compress the sealing material 4 from two directions 401 in the longitudinal direction L of the sealing material 4 and the inclined direction 405 of the sealing material 4. It becomes easy to keep the amount of crushing the sealing material 4 constant, and variation in the crushing rate (compression rate) of the sealing material 4 can be reduced.
Also in this example, other configurations and reference numerals in the other drawings are the same as those in the first embodiment, and the same operational effects as those in the first embodiment can be obtained.

DESCRIPTION OF SYMBOLS 1 Gas sensor 2A, 2B Cover 3 Lead wire 4 Sealing material 401 Inner 402 Outer 403 Outer peripheral side 404 Inner peripheral side 405 Inclination direction 5 Sensor element 51A, 51B Electrode

Claims (6)

A plurality of lead wires (3) respectively connected to the plurality of electrodes (51A, 51B) of the sensor element (5) and led out in the longitudinal direction (L) of the sensor element (5);
A cover (2A, 2B) covering the connection portion (33) of the plurality of lead wires (3);
A plurality of rubber seals (4) each having a ring shape around a central axis (O) along the longitudinal direction (L), each packaged on the plurality of lead wires (3),
The cover (2A, 2B) includes an inner side (401) in the longitudinal direction (L) of the sealing material (4), an outer side (402) in the longitudinal direction (L) of the sealing material (4), and the sealing material. From the outer peripheral side (403) in the radial direction (R) of (4) and any two directions of the outer side (402) and the inclined direction (405) of the outer peripheral side (403) of the sealing material (4). The gas sensor (1), wherein the sealing material (4) is compressed, and the inner peripheral side (404) in the radial direction (R) of the sealing material (4) is brought into close contact with the lead wire (3). ). The cover (2A, 2B) includes a first cover (2A) that presses the entire inner circumference (401) of the seal material (4) in the longitudinal direction (L), and an outer side of the first cover (2A). And a second cover (2B) that presses the entire circumference of the outer side (402) in the longitudinal direction (L) of the sealing material (4),
The seal material (4) expands toward the outer peripheral side (403) in the radial direction (R) at a position adjacent to the entire circumference on the outer peripheral side (403) in the radial direction (R) of the seal material (4). The gas sensor (1) according to claim 1, wherein a seal space (K1) capable of being formed is surrounded by the first cover (2A) and the second cover (2B). The cover (2A, 2B) includes a first cover (2A) that presses the entire circumference of either the inner side (401) or the outer side (402) in the longitudinal direction (L) of the sealing material (4); A second cover (2B) that overlaps the first cover (2A) from the outside and presses the outer peripheral side (403) in the radial direction (R) of the sealing material (4),
In a position adjacent to the other of the inside (401) and the outside (402) in the longitudinal direction (L) of the sealing material (4), there is a sealing space (K2) in which the sealing material (4) can expand. The gas sensor (1) according to claim 1, wherein the gas sensor (1) is surrounded by the first cover (2A) and the second cover (2B). The cover (2A, 2B) includes a first cover (2A) that presses the entire inner circumference (401) of the seal material (4) in the longitudinal direction (L), and an outer side of the first cover (2A). The entire circumference of the sealing material (4) in the inclined direction (405) is pressed by the inclined portion (25) that is overlapped and inclined so that the inner diameter is reduced toward the outside in the longitudinal direction (L). A second cover (2B),
The seal material (4) expands toward the outer peripheral side (403) in the radial direction (R) at a position adjacent to the entire circumference on the outer peripheral side (403) in the radial direction (R) of the seal material (4). The gas sensor (1) according to claim 1, wherein a seal space (K3) that can be formed is surrounded by the first cover (2A) and the second cover (2B).   The gas sensor (1) according to any one of claims 1 to 4, wherein the sealing material (4) is an O-ring having a circular cross section connected to an annular shape.   The gas sensor (1) according to any one of claims 1 to 5, wherein the sealing material (4) is compressed in a state where a crushing rate is 20 to 40%.

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