JP6791317B2 - Air physical quantity sensor - Google Patents

Description

The present invention relates to an aerophysical quantity sensor that detects a specific physical quantity of air flowing through a distribution passage.

Conventionally, an aerophysical quantity sensor in which a sensor element that outputs a detection signal corresponding to a specific physical quantity is contained in a body recess of a sensor body that is opened at a body opening is widely known.

In the disclosed sensor of Patent Document 1 as a kind of such an aerophysical quantity sensor, a sensor filter is fixed to a sensor cap having a cap window portion penetrating between a circulation passage and a body opening. As a result, the sensor filter can prevent the sensor element in the body recess from being deteriorated by foreign matter in the air by filtering the air flowing into the body recess from the flow passage through the cap window and the body opening. It has become. Further, in the disclosed sensor of Patent Document 1, the sensor filter is arranged between the body recess and the sensor cap so as to be as close as possible to the sensor element in the body recess. As a result, the internal volume of the body recess is reduced, so that the arrival time of air from the circulation passage to the sensor element is shortened, so that the detection response by the sensor element can be improved.

Japanese Patent No. 5826355

By the way, in the disclosed sensor of Patent Document 1, one side of the sensor filter is fixed to the outer surface or the inner surface of the sensor cap by adhesion or welding with a part thereof. As a result, in the case of fixing by adhesive, the adhesive surface area becomes small, so that the sensor filter may be peeled off due to deterioration of the adhesive or the like. Further, in the case of fixing by welding, since the welding surface area becomes small, there is a risk that the sensor filter may peel off due to damage of the welded portion due to vibration or a change in cold heat.

When the sensor filter is peeled off in this way, in the case of fixing on the outer surface of the sensor cap, the sensor filter is separated from the normal position between the body recess and the sensor cap, resulting in deterioration or disappearance of filtration performance and a distribution passage. There is a concern that the sensor filter may flow out to the downstream side. On the other hand, in the case of fixing on the inner surface of the sensor cap, if the sensor filter is peeled off, the sensor filter may be separated from the normal position between the body recess and the sensor cap, resulting in deterioration or disappearance of filtration performance. Will be done.

The present invention has been made in view of the problems described above, and an object of the present invention is to provide an aerophysical quantity sensor that suppresses detachment of a sensor filter.

Hereinafter, the technical means of the invention for achieving the subject will be described. The scope of claims for disclosing the technical means of the invention and the reference numerals in parentheses described in this column indicate the correspondence with the specific means described in the embodiment described in detail later. It does not limit the technical scope of the invention.

The first invention disclosed to solve the above-mentioned problems is
An aerophysical quantity sensor (10) that detects a specific physical quantity related to air in a circulation passage (3, 6, 1006) through which air flows.
A sensor element (54) that outputs a detection signal according to a specific physical quantity, and
A sensor body (52) having a body recess (53) opened at the body opening (53a) and including a sensor element in the body recess.
The sensor board (40) holding the sensor body and
A sensor cover (56,205,3056,4056,5056) having a cover window portion (56f) penetrating between the distribution passage and the body opening and covering the sensor body,
A sensor filter (58, 6058, 7058, 8058) that is sandwiched between the sensor body and the sensor cover and filters air that flows into the body recess from the distribution passage through the cover window and body opening .
A resin body (80) in which a sensor cover is embedded on the outer peripheral side of the sensor body is provided.

According to the first invention as described above, the sensor cover sandwiches the sensor filter between the sensor cover and the sensor body that covers the sensor cover. According to this, it is possible to suppress the situation where the sensor filter is separated from the normal position between the sensor body and the sensor cover . The late, the sensor cover was Hiroshi, sensor filter can suppress a situation in which separates from the normal position to the circulation passage.

Further, in the disclosed second invention, the sensor filter spreads along the virtual plane (S) to form the outer peripheral portion (58a) of the filter.
The body opening and the cover window are contained in the filter region (R) on the inner peripheral side of the contour (58ae) of the outer peripheral portion of the filter in the projection view with respect to the virtual plane.

In the configuration of the first invention, which is the premise configuration of the second invention, the sensor body having the body recess opened at the body opening penetrates between the distribution passage and the body opening. It is covered by a sensor cover having a cover window portion. Under such a premise configuration, the body opening and the cover window are projected onto the virtual plane in the filter region on the inner peripheral side of the contour of the outer peripheral portion of the filter formed by the sensor filter spreading along the virtual plane. It fits in. As a result, the sensor filter is sandwiched between the sensor body and the sensor cover at the outer peripheral portion of the filter for projection vision, so that the sensor filter can be reliably suppressed from being separated from the gap.

It is a partial cross-sectional front view which shows the state which the air physical quantity sensor by 1st Embodiment is applied to the air flow detection unit in an internal combustion engine. It is a perspective view which shows the air flow detection unit to which the aerophysical quantity sensor by 1st Embodiment is applied. It is a partial cross-sectional perspective view which shows the airflow detection unit by 1st Embodiment. It is a top view which shows the aerophysical quantity sensor by 1st Embodiment. It is sectional drawing which shows the aerophysical quantity sensor by 1st Embodiment. It is sectional drawing which shows the sensor main body by 1st Embodiment. It is a top view which shows the sensor main body by 1st Embodiment. It is a schematic diagram for demonstrating the manufacturing method of the sensor main body by 1st Embodiment. It is a schematic diagram for demonstrating the detailed structure of the sensor main body by 1st Embodiment. It is a schematic diagram for demonstrating the detailed structure of the sensor main body by 1st Embodiment. It is a schematic diagram for demonstrating the detailed structure of the sensor filter by 1st Embodiment. It is sectional drawing which shows the sensor main body by 2nd Embodiment. It is a perspective view which shows the sensor main body by 2nd Embodiment. It is a schematic diagram for demonstrating the manufacturing method of the sensor main body by 2nd Embodiment. It is sectional drawing which shows the sensor main body by 3rd Embodiment. It is a top view which shows the sensor main body by 3rd Embodiment. It is a schematic diagram for demonstrating the manufacturing method of the sensor main body by 3rd Embodiment. It is sectional drawing which shows the sensor main body by 4th Embodiment. It is a perspective view which shows the sensor main body by 4th Embodiment. It is sectional drawing which shows the sensor main body by 5th Embodiment. It is a top view which shows the sensor main body by 5th Embodiment. It is sectional drawing which shows the sensor main body by 6th Embodiment. It is a top view which shows the sensor main body by 6th Embodiment. It is a schematic diagram for demonstrating the detailed structure of the sensor main body by 6th Embodiment. It is a schematic diagram for demonstrating the detailed structure of the sensor main body by 6th Embodiment. It is sectional drawing which shows the sensor main body by 7th Embodiment. It is a top view which shows the sensor main body by 7th Embodiment. It is a schematic diagram for demonstrating the detailed structure of the sensor main body by 7th Embodiment. It is a schematic diagram for demonstrating the detailed structure of the sensor main body by 7th Embodiment. It is sectional drawing which shows the sensor main body by 8th Embodiment. It is a schematic diagram for demonstrating the detailed structure of the sensor main body by 8th Embodiment. It is a schematic diagram which shows the modification of FIG. It is a schematic diagram which shows the modification of FIG. It is a schematic diagram which shows the modification of FIG. It is a schematic diagram which shows the modification of FIG. It is a schematic diagram which shows the modification of FIG. It is a top view which shows the modification of FIG. It is a top view which shows the modification of FIG. 27. It is a top view which shows the modification of FIG. It is a top view which shows the modification of FIG. 27. It is a top view which shows the modification of FIG. It is a top view which shows the modification of FIG. It is sectional drawing which shows the modification of FIG. It is sectional drawing which shows the modification of FIG. It is sectional drawing which shows the modification of FIG. It is a top view which shows the modification of FIG. It is a top view which shows the modification of FIG. It is a partial cross-sectional perspective view which shows the modification of FIG. It is sectional drawing for demonstrating the modification of FIG. 48. It is sectional drawing which shows the modification of FIG. It is sectional drawing which shows the modification of FIG.

Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings. In addition, duplicate description may be omitted by assigning the same reference numerals to the corresponding components in each embodiment. When only a part of the configuration is described in each embodiment, the configuration of the other embodiment described above can be applied to the other parts of the configuration. Further, not only the combination of the configurations specified in the description of each embodiment, but also the configurations of a plurality of embodiments can be partially combined even if the combination is not specified.

(First Embodiment)
As shown in FIG. 1, the aerophysical quantity sensor 10 according to the first embodiment of the present invention is applied to the air flow detection unit 2 of the internal combustion engine 1.

The airflow detection unit 2 is attached to the attachment hole 4a of the intake pipe 4 forming the intake passage 3 in the internal combustion engine 1. The airflow detection unit 2 includes a flow detection main body 5 at a position exposed to the intake passage 3. As shown in FIGS. 2 and 3, the flow detection main body 5 forms a bypass passage 6 in the detection body 5a. As shown by the dashed arrows in FIGS. 1 and 3, a part of the intake air flowing through the intake passage 3 and being sucked into the cylinder of the internal combustion engine 1 is diverted from the intake passage 3 to the bypass passage 6.

As shown in FIG. 3, the bypass passage 6 is composed of a first passage portion 7 and a second passage portion 8. The straight first passage portion 7 has both the inlet 7a and the outlet 7b open to the intake passage 3. As shown by the broken line arrow in FIG. 3, the first passage portion 7 allows the intake air to flow between the inlet 7a and the outlet 7b in substantially the same direction as the intake passage 3. The curved second passage portion 8 has an inlet 8a opened in the middle of the first passage portion 7, while an outlet 8b is opened in the intake passage 3. As a result, the second passage portion 8 branches from the first passage portion 7. As shown by the broken line arrow in FIG. 3, the second passage portion 8 circulates the intake air between the inlet 8a and the outlet 8b in the direction opposite to the intake passage 3 and then flows in the same direction as the passage 3. Let me.

The flow detection main body 5 further includes a flow rate sensor 9 together with such a bypass passage 6. The flow rate sensor 9 exposes the sensor element 9a in the second passage portion 8. The sensor element 9a outputs a flow rate signal corresponding to the flow rate of the intake air flowing through the second passage portion 8. The flow rate sensor 9 calculates the flow rate of the intake air in the intake passage 3 by processing the flow rate signal output from the sensor element 9a by the circuit module 9b. The flow rate calculated by the circuit module 9b in this way is transmitted to the engine control unit outside the intake passage 3 by signal transmission through the plurality of terminals 5b of the flow detection main body 5. In this way, the flow detection main body 5 detects the flow rate of the intake air flowing through the intake passage 3 by the sensor element 9a.

As shown in FIGS. 1 and 2, the aerophysical quantity sensor 10 is provided integrally with the air flow detection unit 2 as described above. The aerophysical quantity sensor 10 is exposed to the intake passage 3 as a “distribution passage” by being arranged outside the bypass passage 6. The aerophysical quantity sensor 10 has a predetermined width in the flow direction of the intake air in the intake passage 3 shown by the broken arrow in FIG. 1, and exhibits a thick band shape extending linearly in the direction perpendicular to the flow direction as a whole. ing. The flow direction of the intake air in the intake passage 3 is the X direction, the longitudinal direction in which the aerophysical quantity sensor 10 extends is the Z direction as the direction perpendicular to the flow direction, and the X direction and the direction perpendicular to the Z direction are the Y directions. , Each defined.

As shown in FIGS. 4 and 5, the aerophysical quantity sensor 10 includes a sensor case 20, a reinforcing plate 30, a sensor substrate 40, a sensor main body 50, a terminal 60, a circuit module 70, and a potting resin body 80. In addition, in order to make the explanation easy to understand, the potting resin body 80 is shown in the state where most of the potting resin body 80 is cut in FIG.

The sensor case 20 is made of a hard resin such as polyphenylene sulfide (PPS). The sensor case 20 has a thick band shape corresponding to the overall outer shape of the aerophysical quantity sensor 10. The sensor case 20 has a connector portion 22 and a housing recess 24. The connector portion 22 is provided at one end in the Z direction, which is the longitudinal direction of the sensor case 20. The accommodating recess 24 is provided in the sensor case 20 on the other end side of the Z-direction provided end portion of the connector portion 22. The accommodating recess 24 is open on the side of the flow detection main body 5 in the Y direction and has a rectangular bottomed hole shape in a plan view in the Y direction. The accommodating recess 24 is filled with the potting resin body 80 in a state of accommodating other partial components 30, 40, 50, 60 of the aerophysical quantity sensor 10.

The reinforcing plate 30 is made of a metal such as stainless steel. The reinforcing plate 30 has a thin band shape that is narrower and shorter than the sensor case 20. The reinforcing plate 30 is positioned and fixed on the bottom surface 24a of the accommodating recess 24 in a surface contact state. As a result, the reinforcing plate 30 is embedded in the potting resin body 80 in the accommodating recess 24.

The sensor substrate 40 is a so-called flexible printed circuit board formed of a soft resin such as polyimide. The sensor substrate 40 has a thin band shape that is narrower and shorter than the sensor case 20 and narrower and longer than the reinforcing plate 30. The sensor substrate 40 is positioned and fixed in a surface contact state on the reinforcing surface 30a on the side of the reinforcing plate 30 opposite to the bottom surface 24a of the accommodating recess 24. As a result, the sensor substrate 40 is embedded in the potting resin body 80 in the accommodating recess 24, and a part 40a in the Z direction, which is the longitudinal direction, is reinforced by the reinforcing plate 30. The sensor substrate 40 has a mounting surface 40b formed by a flat surface on the side opposite to the reinforcing plate 30 in the reinforcing portion 40a formed by the reinforcing plate 30.

The sensor body 50 detects the humidity representing the ratio of water vapor in the intake air as a "specific physical quantity" related to the intake air flowing through the intake passage 3 by the sensor element 54. The sensor body 50 outputs a humidity signal as a "detection signal" according to the humidity of the intake air to be detected from the sensor element 54. The sensor body 50 has a rectangular parallelepiped shape as a whole. The sensor body 50 is mounted on the mounting surface 40b of the reinforcing portion 40a on the sensor board 40. As a result, a part of the sensor body 50 in the Y direction is embedded in the potting resin body 80 in the accommodating recess 24, and the rest in the Y direction is exposed to the intake passage 3 outside the sensor case 20.

A plurality of terminals 60 are provided. Each terminal 60 is made of a metal such as phosphor bronze. Each terminal 60 has a thin band shape that is narrower and shorter than the sensor case 20. The terminals 60 are arranged in the X direction so as to be substantially parallel to each other. In each terminal 60, a part 60a in the Z direction is embedded in the sensor case 20 from the bottom wall 24b forming the bottom surface 24a of the accommodating recess 24, straddling the connector portion 22. In each terminal 60, the remaining portion 60b in the Z direction projects from the connector portion 22 to the outside of the sensor case 20. The remaining 60b of each terminal 60 is electrically connected to the engine control unit via any terminal 5b of the airflow detection unit 2. Here, it is desirable that each terminal 60 is formed of, for example, a thin wall having a thickness of about 0.2 mm and functions as a low thermal conductor. As a result, the heat insulating effect is exerted between the outside including the engine control unit and the circuit module 70 and the sensor element 54, so that the detection error due to the temperature rise of the sensor element 54 can be suppressed.

The circuit module 70 is electrically connected to the sensor element 54 and each terminal 60 via a metal conductor included in the sensor substrate 40. The circuit module 70 has a plurality of circuit elements 72 in order to process the humidity signal output from the sensor element 54. Each circuit element 72 is mounted on the mounting surface 40b of the reinforcing portion 40a on the sensor substrate 40. Of these circuit elements 72, the control circuit 72a calculates the humidity of the intake air in the intake passage 3 from the humidity signal. The humidity calculated by the control circuit 72a in this way is transmitted to the engine control unit by signal transmission through each terminal 60.

The potting resin body 80 is formed of a hard thermosetting resin such as an epoxy resin or polyurethane. The potting resin body 80 is provided so that most of the inside of the accommodating recess 24 is filled. As a result, the potting resin body 80 covers the entire area of the mounting surface 40b, thereby sealing all the circuit elements 72 on the same surface 40b. In each circuit element 72 in the sealed state in this way, for example, an electrical short circuit between each other, individual damage, and the like are suppressed.

(Sensor body)
Next, the detailed configuration of the sensor body 50 will be described.

As shown in FIGS. 6 and 7, the sensor main body 50 includes a sensor body 52, a sensor element 54, a sensor cover 56, and a sensor filter 58.

The sensor body 52 shown in FIG. 6 is formed of a thermosetting resin such as an epoxy resin. The sensor body 52 exhibits a rectangular parallelepiped shape having six surfaces along each direction of X, Y, and Z. One surface 52b of the sensor body 52 is held by the mounting surface 40b by being positioned and fixed on the mounting surface 40b of the sensor board 40 in a surface contact state.

The sensor body 52 has a body recess 53. As shown in FIGS. 6 and 7, the body recess 53 is provided at the center of the sensor body 52 in the X and Z directions. The body recess 53 is open on the side opposite to the sensor substrate 40 in the Y direction, and has a circular bottom hole shape in a plan view in the Y direction. As a result, the body recess 53 is opened at the body opening 53a that penetrates the side surface 52a of the sensor body 52 opposite to the mounting surface 40b. Here, in particular, the body recess 53 of the first embodiment is formed in the shape of a truncated cone hole, so that the diameter increases from its bottom surface 53b toward the body opening 53a.

The sensor element 54 shown in FIG. 6 senses the humidity of the intake air, for example, based on a change in the dielectric constant of the polymer film with a predetermined correlation with respect to a change in the humidity of the intake air flowing through the intake passage 3. .. The sensor element 54 is contained in the body recess 53 by being fixed in position on the bottom surface 53b while being separated from the body opening 53a. The sensor element 54 is electrically connected to the metal conductor on the sensor substrate 40 via a metal conductor (not shown) embedded in the bottom wall 53c forming the bottom surface 53b of the body recess 53 in the sensor body 52. As a result, the sensor element 54 can output a humidity signal that electrically changes according to the sensed humidity to the circuit module 70 shown in FIGS. 4 and 5.

The sensor cover 56 shown in FIG. 6 is formed of a hard resin such as PPS or polybutylene terephthalate (PBT) so that the difference in thermal expansion coefficient between the sensor case 20 and the potting resin body 80 is as small as possible. ing. As shown in FIGS. 6 and 7, the sensor cover 56 is open on the sensor substrate 40 side in the Y direction and has a rectangular bottomed cup shape in a plan view in the Y direction. As a result, the sensor cover 56 is a rectangular flat plate that closes the rectangular tubular cover peripheral wall portion 56b opened at the cover opening 56a and the cover peripheral wall portion 56b on the opposite side of the cover opening 56a in the Y direction. The cover bottom wall portion 56c having a shape is integrally provided.

A sensor body 52 is fitted on the inner peripheral side of the cover peripheral wall portion 56b along the Y direction. As a result, the cover peripheral wall portion 56b surrounds the entire peripheral side of the sensor body 52 in the circumferential direction. As shown in FIG. 6, the cover peripheral wall portion 56b forms a cover opening 56a at an end portion opposite to the cover bottom wall portion 56c in the Y direction. Of the cover peripheral wall portion 56b, the portion 56d that does not reach the cover bottom wall portion 56c from the cover opening portion 56a rushes into the potting resin body 80 and is fixed in position. As a result, the cover peripheral wall portion 56b forms an embedded portion 56d embedded in the potting resin body 80 from the cover opening 56a side on the outer peripheral side of the sensor body 52.

When the sensor cover 56 is embedded and fixed in the potting resin body 80 in order to manufacture the sensor body 50, the thermosetting resin 80a, which is the material for forming the potting resin body 80, is in a heat-melted state as shown in FIG. Inject into the accommodating recess 24 and then cool. At this time, in order to suppress the lifting of the sensor cover 56 due to the internal pressure of the injection resin 80a and continue to immerse the entire area of the buried portion 56d in the thermosetting resin 80a, the load toward the bottom surface 24a side of the accommodating recess 24 is applied. The sensor cover 56 is continuously acted as shown by the white arrow in FIG. In this way, the thermosetting resin 80a is cured on the mounting surface 40b of the sensor substrate 40 to form the potting resin body 80 in which the buried portion 56d of the cover peripheral wall portion 56b is embedded and fixed.

Here, since the thermosetting resin 80a is heat-shrinked as it is cooled and cured, it is possible to increase the fixing strength of the cover peripheral wall portion 56b by the potting resin body 80. Further, the thermosetting resin 80a is cooled and cured by wrapping around the fitting clearance 56i between the sensor body 52 and the cover peripheral wall portion 56b from the cover opening 56a, so that the cover peripheral wall portion 56b by the potting resin body 80 is formed. It is possible to increase the fixing strength of. Further, the thermosetting resin 80a is cooled and cured, and the embedded portion 56d is embedded and fixed in the potting resin body 80, so that the sensor body 52 and the cover bottom wall portion 56c are separated from each other by the sensor filter 58 described in detail later. The outer peripheral portion 58a of the filter is held.

As shown in FIGS. 6 and 7, the cover bottom wall portion 56c is provided substantially perpendicular to the end portion of the cover peripheral wall portion 56b opposite to the cover opening 56a in the Y direction and is continuous. The cover bottom wall portion 56c covers the sensor body 52 from the side opposite to the sensor substrate 40 in the Y direction in a state where the cover peripheral wall portion 56b is fitted to the outer peripheral side of the sensor body 52 and is embedded in the potting resin body 80. ing. The outer surface 56g of the cover bottom wall portion 56c opposite to the sensor body 52 secures a part of the intake passage 3 between the cover bottom wall portion 56c and the detection body 5a of the flow detection main body 5 shown in FIG. As a result, the cover bottom wall portion 56c exposes the outer surface 56g to the intake passage 3 as shown in FIG. The inner surface 56e of the cover bottom wall portion 56c on the side opposite to the outer surface 56g is separated from the side surface 52a of the sensor body 52 opposite to the mounting surface 40b in the Y direction.

As shown in FIGS. 6 and 7, a cover window portion 56f is formed through the cover bottom wall portion 56c at the center portion in the X and Z directions. The cover window portion 56f is exposed to the intake passage 3 and is separated from the body opening 53a in the Y direction. As a result, the cover window portion 56f is provided between the intake passage 3 and the body opening 53a, and penetrates the cover bottom wall portion 56c in the Y direction. The cover window portion 56f has a circular through-hole shape (that is, a cylindrical hole shape) in a plan view in the Y direction.

The sensor filter 58 shown in FIG. 6 is formed in a porous shape with a soft resin such as polytetrafluoroethylene (PTFE). Here, in particular, since the sensor filter 58 formed of PTFE is excellent in chemical resistance and heat resistance, it is unlikely to deteriorate even in the high-temperature intake passage 3 through which the intake air containing oil flows. Further, in particular, since the sensor filter 58 formed of PTFE is excellent in water repellency and oil repellency, it is difficult for water droplets and oil in the intake air to spread inside, so that the filtration performance is unlikely to deteriorate.

As shown in FIGS. 6 and 7, the sensor filter 58 forms a filter outer peripheral portion 58a by exhibiting a flat film shape extending along a virtual plane S that is assumed to be deployed in the X and Z directions. The outer peripheral portion 58a of the filter has a rectangular contour 58ae in a plan view in the Y direction, and is surrounded from the outer peripheral side by the cover peripheral wall portion 56b. In the examples of FIGS. 6 and 7, the contour 58ae of the outer peripheral portion 58a of the filter is formed to have substantially the same size as the outer peripheral contour 52c of the sensor body 52, but the outer peripheral contour of the sensor body 52 is within a range satisfying Equation 1 described in detail later. It may be formed smaller than 52c.

As shown in FIG. 6, one surface 58b in the Y direction of the outer peripheral portion 58a of the filter is in surface contact with the side surface 52a of the sensor body 52 opposite to the mounting surface 40b in a non-bonded state. On the outer peripheral portion 58a of the filter, the side surface 58c opposite to the Y direction is in surface contact with the inner surface 56e of the cover bottom wall portion 56c in a non-bonded state. Due to surface contact with both the sensor body 52 and the cover bottom wall portion 56c, the filter outer peripheral portion 58a is sandwiched between the sensor body 52 and the cover bottom wall portion 56c. As a result, on the inner peripheral side of the sensor filter 58 from the sandwiched portion, one surface 58b is exposed to the intake passage 3 through the cover window portion 56f, and the opposite side surface 58c faces the body opening 53a in the Y direction. ..

In the sensor filter 58 in the sandwiched state, there is a possibility that minute deformation may occur due to the microscopic unevenness of the side elements 52 and 56c in contact with the outer peripheral portion 58a of the filter. However, the specifications (for example, dimensions and materials) of the sensor filter 58 and the side element 52, 56c are set so that such minute deformation can be suppressed within an allowable range that does not interfere with the filtration performance of the sensor filter 58.

Here, the region on the inner peripheral side of the outer peripheral portion 58a of the filter in the projection view in the Y direction with respect to the virtual plane S with respect to the contour 58ae is defined as the filter region R shown with dot hunting in FIG. Under this definition, both the cover window portion 56f and the body opening 53a are housed in the filter region R in the projection view in the Y direction with respect to the virtual plane S (that is, the projection view in FIG. 9). Further, the body opening portion 53a is contained within the contour of the cover window portion 56f in the filter region R in the projection view in the Y direction with respect to the virtual plane S.

In the first embodiment for establishing such a projection view, the body opening portion 53a and the cover window portion 56f having a circular contour and the filter region R having a rectangular contour 58ae are arranged so as to be substantially aligned as shown in FIG. There is. At the same time, in the first embodiment, the diameter A of the circular contour in the body opening 53a, the diameter B of the circular contour in the cover window portion 56f, and the minimum diameter of the rectangular contour 58ae of the filter outer peripheral portion 58a in the filter region R (that is, that is). (Minimum spacing on both sides in the radial direction) C satisfies the following equation 1 as shown in FIG.
A <B <C ... (Equation 1)

With the above configuration, the sensor filter 58 can exhibit filtration performance for the intake air flowing from the intake passage 3 into the body recess 53 through the cover window portion 56f and the body opening 53a. Here, when setting the filtration performance, the carbons 1000 having the smallest particle size among the assumed solid foreign substances in the intake air are in close contact with each other except for leaving a gap 1001 as shown in FIG. 11, and adhere to the sensor filter 58. Imagine the situation. Under such an assumed state, for example, assuming that the minimum particle size φc of each carbon 1000 is about 0.03 μm, the maximum diameter φo of the inscribed circle 1002 in contact with the surface of each carbon 1000 in the gap 1001 is about 0.0046 μm. This is larger than 0.0004 μm, which is the minimum diameter of the gap size through which water vapor in the intake air required for humidity detection can pass. Therefore, the coarseness of the mesh (that is, the size of the void through which the water vapor passes) that determines the filtration performance of the sensor filter 58 is, for example, 0.001 so that the water vapor in the intake air can pass through the sensor filter 58 through the gap 1001. It is set to about 0.003 μm. Further, the thickness between both sides 58b and 58c of the sensor filter 58 is set to, for example, about 0.1 mm in consideration of such roughness of the eyes.

(Action effect)
The effects of the first embodiment described so far will be described below.

According to the first embodiment, the sensor cover 56 sandwiches the sensor filter 58 with the sensor body 52 that covers the sensor cover 56. According to this, it is possible to suppress the situation where the sensor filter 58 is detached from the normal position between the sensor body 52 and the sensor cover 56. Further, the sensor cover 56 is embedded on the outer peripheral side of the sensor body 52 in the potting resin body 80 that seals the circuit element 72 on the mounting surface 40b of the sensor substrate 40 that holds the sensor body 52. As a result, the sensor cover 56 can be firmly fixed to the sensor substrate 40 by curing the potting resin body 80 and has a large buried surface area that can be secured on the outer peripheral side of the sensor body 52. Therefore, the sensor cover 56 whose position is fixed in this way can suppress the situation where the sensor filter 58 is separated from the normal position to the intake passage 3. Further, since the sensor cover 56 is fixed in position by using the potting resin body 80 that seals the circuit element 72, for example, adhesion or welding for fixing the position of the sensor cover 56 to the sensor substrate 40 or the sensor case 20 is performed. Dedicated steps such as, etc. can be omitted.

Further, according to the first embodiment, the bottomed cup-shaped sensor cover 56 holds the sensor filter 58 sandwiched between its own cover bottom wall portion 56c and the sensor body 52 from the outer peripheral side by its own cover peripheral wall portion 56b. It will be in an enclosed state. In the state of being sandwiched and surrounded by the sensor cover 56, it is possible to suppress a situation in which the sensor filter 58 is detached from the normal position between the sensor body 52 and the cover bottom wall portion 56c to the intake passage 3. Further, in the bottomed cup-shaped sensor cover 56, the cover peripheral wall portion 56b surrounding the sensor body 52 from the outer peripheral side is embedded in the potting resin body 80, so that the buried surface area that can be secured on the outer peripheral side is covered. It can be expanded as much as possible within the range of the axial length of the peripheral wall portion 56b. Therefore, the situation where the sensor filter 58 is separated from the normal position to the intake passage 3 can be reliably suppressed by the cover peripheral wall portion 56b of the sensor cover 56 whose position is fixed with respect to the sensor substrate 40.

Further, according to the first embodiment, in the bottomed cup-shaped sensor cover 56, the entire outer peripheral side of the sensor body 52 is covered with the cover peripheral wall portion 56b. According to this, it is difficult for foreign matter to enter the body recess 53 from between the sensor body 52 and the cover peripheral wall portion 56b through between the sensor body 52 and the cover bottom wall portion 56c, and the sensor element due to the foreign matter is prevented from entering. Deterioration of 54 can be suppressed.

In addition, in the first embodiment, the sensor body 52 having the body recess 53 opened at the body opening 53a penetrates the cover window portion 56f between the intake passage 3 and the body opening 53a. It is covered by the sensor cover 56 that it has. Under such a configuration, the body opening 53a and the cover window 56f are located in the filter region R on the inner peripheral side of the contour 58ae of the outer peripheral portion 58a of the filter formed by the sensor filter 58 extending along the virtual plane S. It fits in the projection view with respect to the virtual plane S. As a result, the sensor filter 58 is sandwiched between the sensor body 52 and the sensor cover 56 by the outer peripheral portion 58 of the filter for projection vision, so that the sensor filter 58 can be reliably suppressed from being separated from the gap.

In addition, according to the first embodiment, the body opening 53a is contained in the cover window portion 56f in the filter region R in the projection view with respect to the virtual plane S. According to this, the air that has passed through the cover window portion 56f and the sensor filter 58 from the intake passage 3 flows from the body opening 53a into the body recess 53 without being blocked by the sensor body 52 around the body opening 53a. Can flow in. Therefore, the air from the intake passage 3 can easily reach the sensor element 54 in the body recess 53. Here, the sensor filter 58 along the virtual plane S between the sensor body 52 and the sensor cover 56 comes as close as possible to the sensor element 54 in the body recess 53. As a result, the internal volume of the body recess 53 is reduced, so that the arrival time of air from the intake passage 3 to the sensor element 54 can be shortened. Therefore, according to these reachability and reachability shortening, the detection response by the sensor element 54 can be enhanced.

Furthermore, according to the first embodiment, the air in which foreign matter is easily mixed in the intake passage 3 of the internal combustion engine 1 is prevented from entering the body recess 53 by the sensor filter 58 whose separation is suppressed as described above. It will be filtered. According to this, it is possible to prevent the detached sensor filter 58 from being sucked into the cylinder on the downstream side from the intake passage 3 while suppressing the deterioration of the sensor element 54 in the body recess 53 due to foreign matter.

(Second Embodiment)
The second embodiment of the present invention is a modification of the first embodiment.

As shown in FIGS. 12 and 13, the bottomed cup-shaped sensor cover 2056 according to the second embodiment has a through hole portion 2056h in the cover peripheral wall portion 56b. One through hole portion 2056h is provided on each of the two rectangular tubular four walls facing each other in the cover peripheral wall portion 56b. Each through hole portion 2056h penetrates the cover peripheral wall portion 56b, which is embedded in the potting resin body 80, in the Z direction. Here, in particular, each through hole portion 2056h of the second embodiment opens the end portion of the cover peripheral wall portion 56b on the cover opening 56a side which constitutes the buried portion 56d, and communicates with the opening portion 56a. ing.

As shown in FIG. 14, the thermosetting resin 80a, which is the material for forming the potting resin body 80 in the second embodiment, is filled in each through hole portion 2056h in a heat-melted state, and then the sensor body 52 and the cover. It wraps around the fitting clearance 56i between the peripheral wall portions 56b and is cooled and cured. As a result, as shown in FIG. 12, the potting resin body 80 fills the inside of each through hole portion 2056h and straddles the fitting clearance 56i between the sensor body 52 and the cover peripheral wall portion 56b from each of the through hole portions 2056h. It is provided.

As described above, in the bottomed cup-shaped sensor cover 2056 according to the second embodiment, the potting resin body 80 straddles between the sensor body 52 and the cover peripheral wall portion 56b from the through hole portion 2056h penetrating the cover peripheral wall portion 56b. Will be provided. As a result, in the sensor cover 2056, the surface integration between the sensor body 52 and the cover peripheral wall portion 56b can be added to the buried surface area that can be secured on the outer peripheral side of the sensor body 52. Therefore, the effect of suppressing the situation where the sensor filter 58 is separated from the normal position to the intake passage 3 can be enhanced by effectively utilizing the cover peripheral wall portion 56b of the sensor cover 2056 whose position is fixed with respect to the sensor substrate 40.

(Third Embodiment)
The third embodiment of the present invention is a modification of the second embodiment.

As shown in FIGS. 15 and 16, the bottomed cup-shaped sensor cover 3056 according to the third embodiment has a through hole portion 3056h different from that of the second embodiment in the cover peripheral wall portion 56b. One through hole portion 3056h is provided on each of the four rectangular tubular walls of the cover peripheral wall portion 56b. Each through hole portion 3056h penetrates the cover peripheral wall portion 56b, which is embedded in the potting resin body 80, in the X direction or the Z direction. Here, in particular, each through hole portion 3056h of the third embodiment penetrates the buried portion 56d between the end portions of the cover peripheral wall portion 56b on the cover opening 56a side and the cover bottom wall portion 56c side. ..

Also in such a third embodiment, as shown in FIG. 17, the thermosetting resin 80a is filled in each through hole portion 3056h in a heat-melted state, and then fitted between the sensor body 52 and the cover peripheral wall portion 56b. It wraps around the clearance 56i and is cooled and cured. As a result, as shown in FIG. 15, the potting resin body 80 fills the inside of each through hole portion 3056h and straddles the fitting clearance 56i between the sensor body 52 and the cover peripheral wall portion 56b from each of the through hole portions 3056h. It is provided.

As described above, in the bottomed cup-shaped sensor cover 3056 according to the third embodiment, the through hole portion 3056h penetrates the cover peripheral wall portion 56b between the ends of the cover opening 56a side and the cover bottom wall portion 56c side. There is. According to this, when the thermosetting resin 80a, which is the potting resin body 80 before curing, is injected into the through hole portion 3056h, the internal pressure of the injected resin is utilized to lift the sensor cover 3056 with respect to the sensor substrate 40. Can be suppressed. Therefore, since the sensor cover 3056 is fixed at the desired position with respect to the sensor substrate 40, it is possible to avoid a situation in which the sensor filter 58 between the sensor cover 3056 and the sensor body 52 deviates from the normal position. In the third embodiment in which such an action effect is exhibited, a load according to the first embodiment may be continuously applied under the state of immersion of the embedded portion 56d in the thermosetting resin 80a, and FIG. 27 shows. As shown, it is not necessary to continuously apply the load by utilizing the weight of the sensor cover 3056.

(Fourth Embodiment)
The fourth embodiment of the present invention is a modification of the first embodiment.

As shown in FIGS. 18 and 19, the bottomed cup-shaped sensor cover 4056 according to the fourth embodiment has a plurality of anchor portions 4056j. The anchor portion 4056j projects one by one from two walls of the four rectangular tubular walls facing each other in the cover peripheral wall portion 56b. Each anchor portion 4056j projects from the portion 56d of the cover peripheral wall portion 56b embedded in the potting resin body 80 to the side opposite to the sensor body 52 along the Z direction. Here, in particular, each anchor portion 4056j of the fourth embodiment projects from the buried portion 56d to the opposite side with a substantially constant thickness. Due to such a protruding form, the entire anchor portion 4056j is embedded in the potting resin body 80. As the configuration of the sensor main body 50 other than the above-described configuration, any of the configurations of the second and third embodiments may be adopted instead of the configuration described in the first embodiment.

In the bottomed cup-shaped sensor cover 4056 according to the fourth embodiment, the anchor portion 4056j protruding from the cover peripheral wall portion 56b is embedded on the outer peripheral side of the sensor body 52. As a result, in the sensor cover 4056, the anchor portion 4056j is caught by the cured potting resin body 80, which makes it difficult to pull out, and the surface integration of the anchor portion 4056j is added to the buried surface area that can be secured on the outer peripheral side of the sensor body 52. obtain. Therefore, the cover peripheral wall portion 56b and the anchor portion 4056j of the sensor cover 4056 whose position is fixed with respect to the sensor substrate 40 can enhance the effect of suppressing the situation where the sensor filter 58 is separated from the normal position into the distribution passage.

(Fifth Embodiment)
The fifth embodiment of the present invention is a modification of the first embodiment.

As shown in FIGS. 20 and 21, the bottomed cup-shaped sensor cover 5056 according to the fifth embodiment has an overhanging portion 5056k. The overhanging portion 5056k overhangs the cover bottom wall portion 56c of the sensor cover 5056 toward the inner peripheral side of the cover window portion 56f. Here, in particular, the overhanging portion 5056k of the fifth embodiment projects from two locations facing each other in the radial direction in the cover window portion 56f having a circular contour, and connects the two locations. Further, in particular, the overhanging portion 5056k of the fifth embodiment is in surface contact with the side surface 58c of the sensor filter 58 opposite to the sensor body 52 on the inner surface 56e side of the cover bottom wall portion 56c. As the configuration of the sensor main body 50 other than those described above, any configuration of any of the second to fourth embodiments may be adopted instead of the configuration described in the first embodiment.

By the way, in the unlikely event that the sensor filter 58 is deformed in shape due to vibration, a change in cold heat, or the like and enters the inner peripheral side of the cover window portion 56f, there is a concern that the sensor filter 58 may be detached from the normal position. However, in the sensor cover 5056 according to the fifth embodiment, the situation where the deformed sensor filter 58 enters the inner peripheral side of the cover window portion 56f and is detached is ensured by the overhanging portion 5056k extending to the inner peripheral side. Can be suppressed.

(Sixth Embodiment)
The sixth embodiment of the present invention is a modification of the first embodiment.

As shown in FIG. 22, in the sensor filter 6058 according to the sixth embodiment, one surface 58b of the filter outer peripheral portion 58a is in a surface contact state with the side surface 52a of the sensor body 52 opposite to the mounting surface 40b, for example, by welding or adhesion. It is joined with. As a result, as shown in FIGS. 22 and 23, the outer peripheral portion 58a of the filter forms a body-side joint portion 6058d having a substantially constant width and a continuous annular band shape in a plan view in the Y direction with the sensor body 52. doing.

In the sensor filter 6058 as well, the outer peripheral portion 58a of the filter is formed by bringing the side surface 58c opposite to the sensor body 52 into surface contact with the inner surface 56e of the cover bottom wall portion 56c of the sensor cover 56 shown in FIG. It is sandwiched between the cover bottom wall portions 56c. Further, in the sensor filter 6058 joined to the sensor body 52 in such a sandwiched state, there is a possibility that minute deformation may occur due to the microscopic unevenness of the side elements 52 and 56c in contact with the outer peripheral portion 58a of the filter. However, the specifications (for example, dimensions and materials) of the sensor filter 6058 and the side element 52, 56c are set so that such minute deformation can be suppressed within an allowable range that does not interfere with the filtration performance of the sensor filter 6058.

Here, as shown in FIG. 24, under the definition of the filter region R similar to that of the first embodiment, the body side joint portion 6058d together with the cover window portion 56f and the body opening portion 53a is projected in the Y direction with respect to the virtual plane S. It is housed in the filter area R. Further, the body side joint portion 6058d is located outside the contour of the body opening 53a and outside the contour of the cover window portion 56f in the filter region R in the projection view in the Y direction with respect to the virtual plane S. That is, the body-side joint portion 6058d is provided between the contour 58ae of the outer peripheral portion 58a of the filter and the contour of the cover window portion 56f in the projection view in the Y direction with respect to the virtual plane S.

In the sixth embodiment in which such a projection view is established, the annular band-shaped body side joint portion 6058d, the circular contour body opening 53a and the cover window portion 56f, and the rectangular contour 58ae filter region R are shown in FIG. As shown, they are substantially aligned. At the same time, in the second embodiment, the inner peripheral side diameter D and the outer peripheral side diameter E of the body side joint portion 6058d, the diameter A of the body opening portion 53a, the diameter B of the cover window portion 56f, and the contour 58ae in the filter region R. The minimum diameter C of the above satisfies the following equation 2 as shown in FIG. As the configuration of the sensor main body 50 other than those described above, any configuration of any of the second to fifth embodiments may be adopted instead of the configuration described in the first embodiment.
A <B <D <E <C ... (Equation 2)

As described above, the sensor filter 6058 according to the sixth embodiment is joined to the sensor body 52 in a state of being sandwiched between the sensor body 52 and the sensor cover 56, so that the sensor filter 6058 is surely separated from the normal position between the sensor bodies 52. Can be suppressed.

(Seventh Embodiment)
The seventh embodiment of the present invention is a modification of the first embodiment.

As shown in FIG. 26, in the sensor filter 7058 according to the seventh embodiment, the side surface 58c of the outer peripheral portion 58a of the filter opposite to the sensor body 52 is welded or welded to the inner surface 56e of the cover bottom wall portion 56c of the sensor cover 56, for example. They are joined in a surface contact state by adhesion or the like. As a result, as shown in FIGS. 26 and 27, the outer peripheral portion 58a of the filter forms a cover-side joint portion 7058e having a substantially constant width and a continuous annular band shape in a plan view in the Y direction with the sensor cover 56. doing.

In the sensor filter 7058 as well, the outer peripheral portion 58a of the filter is the sensor body 52 and the cover bottom wall portion 56c by bringing one surface 58b into surface contact with the side surface 52a of the sensor body 52 shown in FIG. 26 opposite to the mounting surface 40b. It is sandwiched between them. Further, in the sensor filter 7058 joined to the sensor cover 56 in such a sandwiched state, there is a possibility that minute deformation may occur due to the microscopic unevenness of the side elements 52 and 56c in contact with the outer peripheral portion 58a of the filter. However, the specifications (for example, dimensions and materials) of the sensor filter 7058 and the side element 52, 56c are set so that such minute deformation can be suppressed within an allowable range that does not interfere with the filtration performance of the sensor filter 7058.

Here, as shown in FIG. 28, under the definition of the filter region R similar to that of the first embodiment, the cover side joint portion 7058e together with the cover window portion 56f and the body opening portion 53a is projected in the Y direction with respect to the virtual plane S. It is housed in the filter area R. Further, the cover-side joint 7058e is located outside the contour of the body opening 53a and outside the contour of the cover window 56f in the filter region R in the projection view in the Y direction with respect to the virtual plane S. That is, the cover-side joint portion 7058e is provided between the contour 58ae of the outer peripheral portion 58a of the filter and the contour of the cover window portion 56f in the projection view in the Y direction with respect to the virtual plane S.

In the seventh embodiment in which such a projection view is established, the ring-shaped cover-side joint portion 7058e, the circular contour body opening 53a and the cover window portion 56f, and the rectangular contour 58ae filter region R are shown in FIG. 29. As shown, they are substantially aligned. At the same time, in the seventh embodiment, the inner peripheral side diameter F and the outer peripheral side diameter G of the cover side joint portion 7058e, the diameter A of the body opening 53a, the diameter B of the cover window portion 56f, and the contour 58ae in the filter region R. The minimum diameter C of the above satisfies the following equation 3 as shown in FIG. 29. As the configuration of the sensor main body 50 other than those described above, any configuration of any of the second to fifth embodiments may be adopted instead of the configuration described in the first embodiment.
A <B <F <G <C ... (Equation 3)

As described above, the sensor filter 7058 according to the seventh embodiment is joined to the sensor cover 56 in a state of being sandwiched between the sensor body 52 and the sensor cover 56, so that the sensor filter 7058 is surely separated from the normal position between the two. Can be suppressed.

(Eighth embodiment)
The eighth embodiment of the present invention is a modification in which the sixth and seventh embodiments are combined.

As shown in FIG. 30, the sensor filter 8058 according to the eighth embodiment is joined to the sensor body 52 and the sensor cover 56 that sandwich the sensor body 52 in a surface contact state by, for example, welding or adhesion. As a result, the sensor filter 8058 forms a body-side joint portion 6058d similar to the sixth embodiment and a cover-side joint portion 7058e similar to the seventh embodiment.

Here, under the definition of the filter region R similar to that of the first embodiment, both the projection vision similar to that of the seventh embodiment and the projection vision similar to that of the eighth embodiment are realized. Further, in the seventh embodiment in which such a projection view is established, as shown in FIG. 31, the inner peripheral side diameter D of the body side joint portion 6058d and the inner peripheral side diameter F of the cover side joint portion 7058e substantially coincide with each other. There is. At the same time, in the seventh embodiment, the outer peripheral side diameter E of the body side joint portion 6058d and the outer peripheral side diameter G of the cover side joint portion 7058e are substantially the same. As the configuration of the sensor main body 50 other than those described above, any configuration of any of the second to fifth embodiments may be adopted instead of the configuration described in the first embodiment.

Since the sensor filter 8058 according to the eighth embodiment is joined to the elements 52 and 56 on both sides of the sensor filter 8058 while being sandwiched between the sensor body 52 and the sensor cover 56, the sensor filter 8058 from the normal position between them is used. Withdrawal can be reliably suppressed for a long period of time.

(Other embodiments)
Although a plurality of embodiments of the present invention have been described above, the present invention is not construed as being limited to those embodiments, and various embodiments and combinations are included within the scope of the gist of the present invention. Can be applied.

As a modification 1 relating to the first to eighth embodiments, the cover window portion 56f is contained within the contour of the body opening 53a in the filter region R shown in FIG. 32 in the projection view in the Y direction with respect to the virtual plane S. It may have been. As a result, in the modified example 1 relating to the first to fifth embodiments, the following equation 4 is satisfied as shown in FIG. 33. Further, in the first modification relating to the sixth and eighth embodiments, the following equation 5 is satisfied as shown in FIG. 34. Furthermore, in the first modification relating to the seventh and eighth embodiments, the following equation 6 is satisfied as shown in FIG. 34. 32 and 33 show the first modification, and FIG. 34 shows the first modification regarding the eighth embodiment.
B <A <C ... (Equation 4)
B <A <D <E <C ... (Equation 5)
B <A <F <G <C ... (Equation 6)

As a modification 2 relating to the sixth and eighth embodiments, the body side joint portion 6058d is within the contour of the cover window portion 56f in the filter region R shown in FIG. 35 in the projection view in the Y direction with respect to the virtual plane S. Moreover, it may be located outside the contour of the body opening 53a. That is, the body-side joint portion 6058d may be provided between the contour of the body opening 53a and the contour of the cover window portion 56f in the projection view in the Y direction with respect to the virtual plane S. In such a modification 2, the following equation 7 is satisfied as shown in FIG. 36. Note that FIGS. 35 and 36 show a modification 2 relating to the sixth embodiment.
A <D <E <B <C ... (Equation 7)

As a modification 3 according to the eighth embodiment, the inner peripheral side diameter D of the body side joint portion 6058d and the inner peripheral side diameter F of the cover side joint portion 7058e may be different. As a modification 4 according to the eighth embodiment, the outer peripheral side diameter E of the body side joint portion 6058d and the outer peripheral side diameter G of the cover side joint portion 7058e may be different.

As a modification 5 relating to the sixth and eighth embodiments, the body side joint portion 6058d is formed so as to exhibit a shape other than the annular band shape in a plan view in the Y direction, for example, the rectangular band shape shown in FIG. 37. You may. As a modification 6 relating to the seventh and eighth embodiments, the cover-side joint portion 7058e is formed so as to exhibit a shape other than the annular band shape, for example, the rectangular band shape shown in FIG. 38 in a plan view in the Y direction. You may. Note that FIG. 37 shows a modification 5 relating to the sixth embodiment, and FIG. 38 shows a modification 6 relating to the seventh embodiment.

As a modification 7 relating to the sixth and eighth embodiments, as shown in FIG. 39, body-side joints 6058d may be provided at a plurality of locations in the circumferential direction on the outer peripheral portion 58a of the filter at intervals from each other. .. As a modification 8 relating to the seventh and eighth embodiments, as shown in FIG. 40, cover-side joints 7058e may be provided at a plurality of locations on the outer peripheral portion 58a of the filter in the circumferential direction at intervals from each other. .. Note that FIG. 39 shows a modification 7 according to the sixth embodiment, and FIG. 40 shows a modification 8 according to the seventh embodiment.

As a modification 9 relating to the first to eighth embodiments, the body opening 53a may be formed so as to exhibit a shape other than a circle, for example, a rectangle shown in FIG. 41 in a plan view in the Y direction. As a modification 10 regarding the first to eighth embodiments, the cover window portion 56f may be formed so as to exhibit a shape other than a circle, for example, a rectangle shown in FIG. 41 in a plan view in the Y direction. As a modification 11 regarding the first to eighth embodiments, the outer peripheral portion 58a of the filter is formed so as to have a shape other than a rectangle, for example, a contour 58ae such as a circle shown in FIG. 42 in a plan view in the Y direction. May be good. In addition, FIG. 41 shows the modified examples 9 and 10 regarding the first embodiment, and FIG. 42 shows the modified example 11 regarding the first embodiment.

The sensor filters 58, 6058, 7058, 8058 of the modified example 12 relating to the first to eighth embodiments are not limited to the porous filter formed by PTFE, and are, for example, waterproof and breathable, and the sixth to sixth. (Viii) In the case of the embodiment, a fibrous filter formed of another material may be adopted in consideration of bondability and the like. As a modification 13 relating to the first to eighth embodiments, for example, a plurality of filter elements 58f having different materials, roughness, thickness, etc. are laminated as shown in FIG. 43 to form sensor filters 58, 6058. , 7058, 8058 may be formed. As a modification 14 relating to the first to eighth embodiments, the sensor substrate 40 is composed of a hard substrate such as a glass epoxy substrate other than the soft flexible printed circuit board, so that the reinforcing plate 30 is formed as shown in FIG. It may be omitted. It should be noted that FIGS. 43 and 44 show modifications 13 and 14 of the first embodiment, respectively.

The anchor portion 4056j of the modified example 15 according to the fourth embodiment is formed in a protruding form other than the protruding form having a constant thickness, for example, as shown in FIG. 45, the thickness becomes thinner toward the protruding side. May be good. The overhanging portion 5056k of the modified example 16 according to the fifth embodiment may be formed in an overhanging form as shown in FIGS. 46 and 47, other than the overhanging form in which the two points of the cover window portion 56f are connected. Good. Here, in the cover window portion 56f of the modified example 15 shown in FIG. 46, an overhanging portion 5056k that connects two locations facing each other in the radial direction and an overhanging portion connecting two other locations facing each other in the radial direction are connected. The 5056k projectes toward the inner circumference. On the other hand, the cover window portion 56f of the modified example 16 shown in FIG. 47 projects from two locations facing each other in the radial direction toward the inner peripheral side with a length that does not reach the center of the circular contour.

As a modification 17 relating to the first to eighth embodiments, as shown in FIG. 48, the aerophysical quantity sensor 10 is integrally configured with the air flow detection unit 2, so that the sensor is connected to the second passage portion 8 of the bypass passage 6. The main body 50 may be exposed. Here, in the modified example 17 shown in FIG. 48, the sensor case 20 is shared with the detection body 5a of the flow detection main body 5, and the terminal 60 is shared with the terminal 5b of the flow detection main body 5. Further, in the modification 17 shown in FIG. 48, the sensor main body 50 and the circuit module 70 are mounted on the sensor board 40 together with the sensor element 9a and the circuit module 9b. As a result, the sensor filter 58 of the sensor body 50 filters a part of the intake air that flows into the body recess 53 from the bypass passage 6 as the “circulation passage” through the cover window portion 56f and the body opening 53a. It becomes. In FIG. 48, the illustration of each component constituting the sensor main body 50 of the applied embodiment is omitted.

As a further modification 18 of the modification 17 relating to the first to eighth embodiments, another bypass passage separated from the bypass passage 6 and having the inlet 1006a and the outlet 1006b opened in the intake passage 3 as shown in FIG. 49. The sensor body 50 may be exposed in the other bypass passage 1006 with 1006 as the “circulation passage”. However, in the case of the modification 18, the sensor board 40 on which the sensor element 9a and the circuit module 9b are not mounted is adopted as in the first embodiment. In FIG. 49, the illustration of each component constituting the sensor main body 50 of the applied embodiment is omitted.

As a modification 19 relating to the first to eighth embodiments, as shown in FIG. 50, the hole 53d penetrating the sensor body 52 in the Y direction is closed by the sensor substrate 40 on which the sensor element 54 is mounted. , The body recess 53 may be formed. As a modification 20 according to the first to eighth embodiments, even if the sensor element 54 senses and detects a specific physical quantity other than humidity related to air, for example, temperature, pressure, thermal conductivity, concentration, or flow rate. Good. As a modification 21 according to the first to eighth embodiments, as shown in FIG. 51, a plurality of sensor elements 54 having different or the same specific physical quantities to be detected may be included in the body recess 53. Note that FIGS. 50 and 51 show modifications 19 and 21 of the first embodiment, respectively.

1 Internal combustion engine, 2 Airflow detection unit, 3 Intake passage, 6,1006 Bypass passage, 10 Air physical quantity sensor, 20 Sensor case, 40 Sensor board, 40b mounting surface, 50 Sensor body, 52 Sensor body, 53 Body recess, 53a body Opening, 54 sensor element, 56,205,3056,4056,5056 Sensor cover, 56a cover opening, 56b cover peripheral wall, 56c cover bottom wall, 56f cover window, 56i fitting clearance, 58,6058,7058 , 8058 sensor filter, 58a filter outer circumference, 58ae contour, 70 circuit module, 72 circuit element, 80 potting resin body, 2056h, 3056h through hole part, 4056j anchor part, 5056k overhang part, 6058d body side joint part, 7058e cover Side junction, R filter area, S virtual plane

Claims (12)

An aerophysical quantity sensor (10) that detects a specific physical quantity related to air in a circulation passage (3, 6, 1006) through which air flows.
A sensor element (54) that outputs a detection signal corresponding to the specific physical quantity, and
A sensor body (52) having a body recess (53) opened at the body opening (53a) and including the sensor element in the body recess.
The sensor substrate (40) holding the sensor body and
A sensor cover (56,205,3056,4056,5056) having a cover window portion (56f) penetrating between the distribution passage and the body opening and covering the sensor body.
A sensor filter (58, 6058, 7058, which is sandwiched between the sensor body and the sensor cover and filters the air flowing into the body recess from the flow passage through the cover window and the body opening. 8058) and
An aerophysical quantity sensor including a resin body (80) in which the sensor cover is embedded on the outer peripheral side of the sensor body . The sealed by a resin body, air physical quantity sensor according to claim 1, further comprising a circuit element (72) for processing the detection signal. The sensor cover has a bottomed cup shape that is opened at the cover opening (56a), and the cover bottom wall portion (56c) that sandwiches the sensor filter with the sensor body, and the sensor. It has a cover peripheral wall portion (56b) that surrounds the body and the sensor filter from the outer peripheral side.
The aerophysical quantity sensor according to claim 1 or 2 , wherein the cover peripheral wall portion is embedded in the resin body from the cover opening side. The sensor cover (4056) has an anchor portion (4056j) protruding from the cover peripheral wall portion.
The aerophysical quantity sensor according to claim 3 , wherein the anchor portion is embedded in the resin body. The aerophysical quantity sensor according to claim 3 or 4 , wherein the sensor cover (56) covers the entire outer peripheral side of the sensor body with the cover peripheral wall portion. The sensor cover (2056, 3056) has through hole portions (2056h, 3056h) penetrating the cover peripheral wall portion.
The aerophysical quantity sensor according to claim 3 or 4, wherein the resin body is provided so as to straddle between the through hole portion, the sensor body, and the cover peripheral wall portion. The aerophysical quantity sensor according to claim 6 , wherein the through hole portion (3056h) penetrates the cover peripheral wall portion between the end portions on the cover opening side and the cover bottom wall portion side. The aerophysical quantity sensor according to any one of claims 1 to 7 , wherein the sensor cover (5056) has an overhanging portion (5056k) protruding toward the inner peripheral side of the cover window portion. The sensor filter extends along a virtual plane (S) to form a filter outer peripheral portion (58a).
Claims 1 to 8 show that the body opening and the cover window are contained in the filter region (R) on the inner peripheral side of the contour (58ae) of the outer peripheral portion of the filter in the projection view with respect to the virtual plane. The aerophysical quantity sensor according to any one item. The aerophysical quantity sensor according to claim 9 , wherein the body opening is housed in the cover window in the projected view. The aerophysical quantity sensor according to any one of claims 1 to 10 , wherein the sensor filter (6058, 7058, 8058) is joined to at least one of the sensor body and the sensor cover. The aerophysical quantity sensor according to any one of claims 1 to 11 , wherein the sensor filter (58) filters the air flowing through the intake passage (3) as the circulation passage in the internal combustion engine (1).

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