Sound detection device

Abstract

This suppresses a decrease in the detection accuracy of the sensor unit. [Solution] The device comprises a sensor unit 40 that outputs a detection signal corresponding to sound, a case 10 in which the sensor unit 40 is arranged, and a cover unit 70 assembled to the case 10 to protect the sensor unit 40. The cover unit 70 has an inner cover unit 80 arranged on the side of the sensor unit 40, and an outer cover unit 90 arranged on the opposite side of the sensor unit 40, sandwiching the inner cover unit 80, and covering the inner cover unit 80. The inner cover unit 80 is made of a windscreen member which is a porous material, and the outer cover unit 90 is made of a hard material which has a higher Young's modulus than the inner cover unit 80, and has a configuration in which a plurality of holes 91 are formed that penetrate between the inner surface 90b located on the side of the inner cover unit 80 and the outer surface 90a on the opposite side of the inner surface 90b.

Description

Technical Field

[0001] The present disclosure relates to a sound detection device.

Background Art

[0002] Conventionally, a sound detection device including a cover portion has been proposed (see, for example, Patent Document 1). Specifically, in this sound detection device, a cover portion is arranged so that foreign matter hardly reaches a sensor portion that outputs a detection signal according to sound. The cover portion is composed of a mesh or the like in which holes are formed, and is configured to introduce sound through the holes.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in such a sound detection device, foreign matter such as water may enter through the holes of the cover portion. For example, when the sound detection device is used as a detection unit for detecting sound generated from a machine tool, since the sound detection device is arranged in an environment where foreign matter such as water or oil is likely to scatter, the possibility of foreign matter entering through the holes of the cover is increased. And when foreign matter reaches the sensor portion, the detection accuracy of the sensor portion may decrease.

[0005] An object of the present disclosure is to suppress a decrease in the detection accuracy of the sensor portion.

Means for Solving the Problems

[0006] According to one aspect of this disclosure, the sound detection device comprises a sensor unit (40) that outputs a detection signal corresponding to sound, a case (10) in which the sensor unit is arranged, and a cover unit (70) assembled to the case to protect the sensor unit. The cover unit has an inner cover unit (80) located on the side of the sensor unit and an outer cover unit (90) located on the opposite side of the sensor unit, sandwiching the inner cover unit, and covering the inner cover unit. The inner cover unit is made of a windscreen member which is a porous material, and the outer cover unit is made of a hard member which has a higher Young's modulus than the inner cover unit, and has a plurality of holes (91) formed between an inner surface (90b) located on the side of the inner cover unit and an outer surface (90a) on the opposite side of the inner surface.

[0007] According to this, the cover portion has a configuration consisting of an outer cover portion made of a hard material and an inner cover portion made of a windscreen member made of a porous material. Therefore, even if foreign matter enters through the holes in the outer cover portion, the inner cover portion can prevent the foreign matter from reaching the sensor portion, thereby preventing a decrease in detection accuracy.

[0008] The reference numerals in parentheses attached to each component indicate an example of the correspondence between that component and the specific components described in the embodiments described later. [Brief explanation of the drawing]

[0009] [Figure 1] This is a cross-sectional view of the sound detection device in the first embodiment. [Figure 2] This is a cross-sectional view of the sound detection device in the second embodiment. [Figure 3] This is a cross-sectional view of the sound detection device in the third embodiment. [Figure 4] This is a plan view of the cover in the fourth embodiment. [Figure 5] This is a cross-sectional view of the vicinity of the outer edge of the lid in the fifth embodiment. [Figure 6] This is a cross-sectional view of the sound detection device in the sixth embodiment. [Figure 7]This is a cross-sectional view illustrating the condition when a foreign object enters the inside of the cover. [Figure 8] This is a cross-sectional view of the sound detection device in the seventh embodiment. [Figure 9] This is a cross-sectional view illustrating incident sound, reflected sound, and diffracted sound. [Figure 10] This is a cross-sectional view of the sound detection device in the eighth embodiment. [Figure 11] This is a cross-sectional view of the sound detection device in the ninth embodiment. [Figure 12] This is a cross-sectional view of the sound detection device in the tenth embodiment. [Figure 13] This is a cross-sectional view of the sound detection device in the 11th embodiment. [Figure 14] This is a cross-sectional view of the sound detection device in the 12th embodiment. [Figure 15] This is a cross-sectional view of the sound detection device in the 13th embodiment. [Modes for carrying out the invention]

[0010] The embodiments of this disclosure will be described below with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other will be denoted by the same reference numerals.

[0011] (First Embodiment) The first embodiment will be described with reference to the drawings. The sound detection device S1 of this embodiment is preferably used as a detection unit for detecting sounds generated from, for example, a machine tool.

[0012] As shown in Figure 1, the sound detection device S1 is configured to include a case 10, a wiring board 30, a sensor unit 40, a waterproof membrane 60, a cover unit 70, and the like.

[0013] The case 10 is configured by assembling the connector case 20 and the lid portion 50. The connector case 20 is formed into a substantially cylindrical shape made of, for example, a heat-resistant resin material such as PPS (that is, polyphenylene sulfide) or a metal material such as SUS. And, the connector case 20 of the present embodiment is configured such that a stepped portion 23 is provided between the first portion 21 on one end side and the second portion 22 on the other end side. Specifically, the circumferential length of the first portion 21 of the connector case 20 is made longer than the circumferential length of the second portion 22. In other words, in the cross section along the axial direction, the length of the opposing side surface of the first portion 21 of the connector case 20 is made longer than the length of the opposing side surface of the second portion 22. In FIG. 1, the upper portion of the connector case 20 on the paper surface becomes the first portion 21, and the lower portion on the paper surface becomes the second portion 22. Also, in FIG. 1, the vertical direction of the paper surface is the axial direction, and the circumferential direction is the direction around the axial direction. Further, the cross section along the axial direction is, for example, as shown in FIG. 1.

[0014] A recess 24 is formed in one surface 20a on one end side of the connector case 20. In the present embodiment, one surface 20a of the connector case 20 is formed such that the normal direction with respect to one surface 20a (hereinafter, also simply referred to as the normal direction) coincides with the axial direction. Further, an annular groove portion 25 is formed in the side surface 20b connected to one surface 20a of the connector case 20, and a sealing member 26 such as an O-ring is disposed in the groove portion 25. In the present embodiment, the groove portion 25 is formed so as to go around the side surface 20b of the first portion 21 in the circumferential direction. The lid portion 50 constituting the case 10 will be described later.

[0015] The wiring board 30 is composed of a printed board or the like having one surface 30a and the other surface 30b. Although not particularly shown in the present embodiment, one-side wiring is formed on the one surface 30a side, the other-side wiring is formed on the other surface 30b side, and through-hole wiring for connecting the one-side wiring and the other-side wiring is appropriately formed. And, the wiring board 30 is disposed in the recess 24 in a state where the other surface 30b faces the bottom surface of the recess 24.

[0016] Furthermore, the wiring board 30 has a through hole 31 formed on its outer edge that penetrates between one surface 30a and the other surface 30b, and a terminal 27 is inserted through the through hole 31. The wiring board 30 is connected to the terminal 27 by placing a conductive material 32, such as solder, in the through hole 31. The terminal 27 is, for example, rod-shaped and is placed inside the connector case 20. Specifically, the terminal 27 is positioned in the connector case 20 such that the end on the wiring board 30 side is exposed from the recess 24, and the end on the opposite side of the wiring board 30 is exposed from a predetermined location in the connector case 20. The terminal 27 connects the wiring board 30 and the external circuit section by connecting the end on the opposite side of the wiring board 30 to the external circuit section.

[0017] The sensor unit 40 is configured to include a detection element that outputs a detection signal corresponding to the applied sound, and is arranged on one side 30a of the wiring board 30 and electrically connected to the wiring board 30. In this way, the sensor unit 40 is connected to the external circuit unit via the wiring board 30 and terminal 27. The detection element is not particularly limited, but can be composed of piezoelectric, electrostatic, or capacitor types, for example. The sensor unit 40 may also be a package in which the detection element is housed in a box-shaped housing with an introduction hole for introducing sound, or it may consist only of the detection element.

[0018] The lid portion 50 is made of a metal material such as SUS, and is a bottomed cylindrical shape having a bottom portion 51 and side portions 52. The lid portion 50 is assembled to the connector case 20 by crimping the open end 52a of the side portion 52 to the stepped portion 23 of the connector case 20, so that the sealing member 26 is crushed by the side portion 52 while the bottom portion 51 faces one surface 20a of the connector case 20. Furthermore, by assembling the lid portion 50 to the connector case 20 in this way, a housing space 41 is formed between the lid portion 50 and the recess 24 of the connector case 20, and the sensor portion 40 is positioned in the housing space 40.

[0019] Hereinafter, the bottom portion 51 will be described with the side opposite to the sensor portion 40 as one side 51a and the side facing the sensor portion 40 as the other side 51b.

[0020] In this embodiment, the lid 50 has a protrusion 53 formed in the center of the bottom 51, projecting toward one side 51a. In other words, the lid 50 has a stepped portion 54 formed on the outer edge of the bottom 51, recessed toward the other side 51b. That is, in this embodiment, one side 51a and the other side 51b of the bottom 51 have the central part protruding toward the one side 51a than the outer edge. The protrusion 53 is sized to accommodate a part of the sensor part 40 inside. The lid 50 is assembled to the connector case 20 so that a part of the sensor part 40 is housed within the protrusion 53.

[0021] Furthermore, the lid portion 50 has a through-hole 55 formed in the portion of the bottom portion 51 facing the sensor portion 40, extending between one surface 51a and the other surface 51b. As a result, sound is applied to the sensor portion 40 through the through-hole 55. In this embodiment, a protrusion 53 is formed in the center of the lid portion 50, and the through-hole 55 is formed in the protrusion 53. The space inside the through-hole 55 becomes a so-called acoustic space 56, and its size is appropriately changed according to the frequency of the sound to be detected.

[0022] Furthermore, the lid portion 50 is formed with a first engaging fixing portion 501 for engaging with the inner cover portion 80 (described later) to fix the inner cover portion 80, and a second engaging fixing portion 502 for engaging with the outer cover portion 90 (described later) to fix the outer cover portion 90. In this embodiment, the first engaging fixing portion 501 is formed at the outer edge end of the protrusion 53 and is a protrusion that protrudes along the surface direction of one surface 51a. The second engaging fixing portion 502 is formed at the outer edge end of the stepped portion 54 and is a protrusion that protrudes along the surface direction of one surface 51a.

[0023] The waterproof membrane 60 is made of a porous material such as fluororesin. The waterproof membrane 60 is positioned to close the through-hole 55 of the lid 50. In this embodiment, the waterproof membrane 60 is positioned on one side 51a of the bottom 51, but the waterproof membrane 60 may also be positioned on the other side 51b of the bottom 51. In this embodiment, the waterproof membrane 60 corresponds to a protective membrane. In this embodiment, the waterproof membrane 60 is positioned because a situation in which water as a foreign substance may penetrate is assumed, but in a situation in which oil as a foreign substance may penetrate, an oil-repellent membrane may be positioned instead of the waterproof membrane 60.

[0024] The cover portion 70 is assembled to the case 10 to protect the sensor portion 40, and in this embodiment, it has a configuration having an inner cover portion 80 and an outer cover portion 90. The outer cover portion 90 is positioned to cover the inner cover portion 80.

[0025] Specifically, the inner cover portion 80 is made of a windscreen member which is a porous material such as sponge, and is hemispherical in shape with an outer surface 80a and an inner surface 80b. The inner cover portion 80 in this embodiment is roughly bowl-shaped with a recess formed on the inside so that a cavity is formed on the inner surface 80b side. The inner cover portion 80 may be made of a material which readily absorbs (i.e., readily attenuates) specific frequencies. For example, if it is to absorb sounds related to human voices, the inner cover portion 80 may be made of a material which readily absorbs sounds in the 3-4 kHz range.

[0026] Furthermore, the inner cover portion 80 has a third engaging fixing portion 81 formed on its inner surface 80b, which corresponds to the first engaging fixing portion 501 of the lid portion 50. The inner cover portion 80 is fixed to the lid portion 50 by the engagement of the third engaging fixing portion 81 and the first engaging fixing portion 501, with the outer edge of the inner cover portion 80 in contact with the stepped portion 54 of the lid portion 50. In this embodiment, the third engaging fixing portion 81 is a recess, and the protrusion of the first engaging fixing portion 501 is snap-fitted into this recess.

[0027] Furthermore, in this embodiment, the inside of the inner cover portion 80 is hollow. Therefore, when the inner cover portion 80 is fixed to the lid portion 50, an internal space 100 is formed between the inner cover portion 80 and the lid portion 50.

[0028] The outer cover portion 90 is made of a hard material such as metal or resin with a higher Young's modulus than the inner cover portion 80, and has holes 91 formed therein that allow foreign matter to enter more easily than the inner cover portion 80. In this embodiment, the outer cover portion 90 is made of a mesh material formed by weaving metal wires into a net, or perforated metal, etc.

[0029] The outer cover portion 90 is hemispherical in shape with a circular arc cross-section corresponding to the inner cover portion 80, so as to cover the inner cover portion 80. In the following description, the outer cover portion 90 will be described with the side facing the inner cover portion 80 as the inner surface 90b and the side opposite to the inner cover portion 80 as the outer surface 90a.

[0030] The outer cover portion 90 has a fourth engaging fixing portion 92 formed at its outer edge. The outer cover portion 90 is fixed to the lid portion 50 by the engagement of the fourth engaging fixing portion 92 and the second engaging fixing portion 502. In this embodiment, the fourth engaging fixing portion 92 is a protrusion, and this protrusion is snap-fitted to the protrusion of the second engaging fixing portion 502.

[0031] Furthermore, in this embodiment, the inner cover portion 80 and the outer cover portion 90 are fixed to the lid portion 50 with a predetermined space (i.e., gap) 110 between the inner cover portion 80 and the outer cover portion 90. Therefore, foreign matter that enters the interior through the hole 91 of the outer cover portion 90 is more likely to move along the inner surface 90b of the outer cover portion 90 than to move to the inner cover portion 80. Thus, it is possible to suppress foreign matter from reaching the inner cover portion 80 and then reaching the sensor portion 40 via the inner cover portion 80.

[0032] The above describes the configuration of the sound detection device S1 in this embodiment. Such a sound detection device S1 is placed, for example, near the part of the object to be detected that emits the sound. The sensor unit 40 outputs a detection signal corresponding to the sound when the sound generated by the object passes through the cover unit 70, the internal space 100, and the acoustic space 56 and is applied to it.

[0033] According to the embodiment described above, the cover portion 70 has a configuration comprising an outer cover portion 90 made of a hard material and an inner cover portion 80 made of a windscreen member made of a porous material. Therefore, even if foreign matter enters through the holes 91 of the outer cover portion 90, the inner cover portion 80 can prevent the foreign matter from reaching the sensor portion 40, thereby preventing a decrease in detection accuracy. Furthermore, since the outer cover portion 90 is made of a hard material, impact resistance can also be improved.

[0034] (1) In this embodiment, a space 110 is formed between the inner cover portion 80 and the outer cover portion 90. Therefore, foreign matter that enters the interior through the hole 91 of the outer cover portion 90 is more likely to move along the inner surface 90b of the outer cover portion 90 than to move to the inner cover portion 80. Thus, it is possible to suppress foreign matter from reaching the inner cover portion 80 and then reaching the sensor portion 40 via the inner cover portion 80.

[0035] (2) In this embodiment, the waterproof membrane 60 is positioned to close the through hole 55. This further suppresses water as foreign matter from reaching the sensor part 40.

[0036] (Second Embodiment) A second embodiment will now be described. This embodiment is a modification of the first embodiment in which the configuration of the inner cover portion 80 and the outer cover portion 90 is changed. Other aspects are the same as in the first embodiment, so a detailed explanation will be omitted here.

[0037] The sound detection device S1 of this embodiment is designed to handle situations where water, as a foreign substance, may enter. As shown in Figure 2, the inner cover portion 80 has a water-repellent portion 82 formed on its outer surface 80a. The outer cover portion 90 has a water-repellent portion 93 formed on its outer surface 90a. The water-repellent portions 82 and 93 are composed of, for example, an organic fluorine compound film.

[0038] According to the embodiment described above, since the cover portion 70 has an outer cover portion 90 and an inner cover portion 80, the same effects as in the first embodiment can be obtained.

[0039] (1) In this embodiment, a water-repellent portion 82 is formed on the inner cover portion 80, and a water-repellent portion 93 is formed on the outer cover portion 90. Therefore, it is possible to suppress the accumulation of water as foreign matter in the cover portion 70, and furthermore, to suppress foreign matter from reaching the sensor portion 40.

[0040] (Modified version of the second embodiment) A modified version of the second embodiment described above will now be explained. In the second embodiment described above, when the sound detection device S1 is used in a situation in which oil as a foreign substance may enter, the inner cover portion 80 may have an oil-repellent portion instead of a water-repellent portion 82, and the outer cover portion 90 may have an oil-repellent portion instead of a water-repellent portion 93. The oil-repellent portion is made of, for example, a fluorine-based polymer.

[0041] Furthermore, in the second embodiment described above, the water-repellent portion 82 may be formed on the outer surface 80a and inner surface 80b of the inner cover portion 80, and the water-repellent portion 93 may be formed on the outer surface 90a and inner surface 90b of the outer cover portion 90. Moreover, the water-repellent portion 82 may be formed only on the inner surface 80b of the inner cover portion 80, and the water-repellent portion 93 may be formed only on the inner surface 90b of the outer cover portion 90. In addition, the water-repellent portion 82 of the inner cover portion 80 and the water-repellent portion 93 of the outer cover portion 90 may be formed only by one of them.

[0042] Furthermore, in the second embodiment described above, the cover portion 70 may be composed of either an inner cover portion 80 or an outer cover portion 90, and water-repellent portions 82 and 93 may be provided on one of these cover portions. In the case where the cover portion 70 is composed only of an inner cover portion 80, the holes in the cover portion 70 are composed of holes in the porous material constituting the inner cover portion 80.

[0043] (Third embodiment) A third embodiment will now be described. This embodiment is a modification of the configuration of the outer cover portion 90 compared to the first embodiment. Other aspects are the same as in the first embodiment, so their explanation will be omitted here.

[0044] As shown in Figure 3, the sound detection device S1 of this embodiment has an outer cover portion 90 that comprises a first outer cover portion 910 and a second outer cover portion 920. Specifically, the first outer cover portion 910 and the second outer cover portion 920 are arranged in the order of the first outer cover portion 910 and the second outer cover portion 920 from the side opposite to the inner cover portion 80, and are integrated by sintering or the like. Therefore, in this embodiment, the outer surface 90a of the outer cover portion 90 is composed of the first outer cover portion 910, and the inner surface 90b of the outer cover portion 90 is composed of the second outer cover portion 920. In this embodiment, an example in which the first outer cover portion 910 and the second outer cover portion 920 are integrated by sintering is described, but the first outer cover portion 910 and the second outer cover portion 920 may also be integrated by adhesive or the like.

[0045] The first outer cover portion 910 has a higher Young's modulus than the second outer cover portion 920. Furthermore, the first outer cover portion 910 has a hole 911, and the second outer cover portion 920 has a hole 921. However, the opening size of the holes 911 and 921 in the second outer cover portion 920 is smaller than that of the first outer cover portion 910. In other words, the opening area of ​​the hole 921 in the second outer cover portion 920 is smaller than that of the hole 911 in the first outer cover portion 910. That is, the hole 921 in the second outer cover portion 920 is sized to make it more difficult for foreign matter to enter than the hole 911 in the first outer cover portion 910. In this case, it is preferable that the hole 921 in the second outer cover portion 920 is sized to at least satisfy IP6X. IP6X means that a substance with a diameter of 1 mm cannot penetrate it. In this embodiment, the hole 91 of the outer cover portion 90 is formed at the point where the hole 911 of the first outer cover portion 910 and the hole 921 of the second outer cover portion 920 are in communication.

[0046] Furthermore, in this embodiment, the second outer cover portion 920 has a thickness t2 that is thinner than the thickness t1 of the first outer cover portion 910.

[0047] According to the embodiment described above, since the cover portion 70 has an outer cover portion 90 and an inner cover portion 80, the same effects as in the first embodiment can be obtained.

[0048] (1) In this embodiment, the outer cover portion 90 is composed of a first outer cover portion 910 and a second outer cover portion 920 integrated together. The hole 921 of the second outer cover portion 920 is smaller than the hole 911 of the first outer cover portion 910. Therefore, compared to the case in which the outer cover portion 90 is composed of only the first outer cover portion 910, the intrusion of foreign matter into the interior can be further suppressed, and the decrease in detection accuracy can be further suppressed.

[0049] (2) In this embodiment, the thickness t2 of the second outer cover portion 920 is thinner than the thickness t1 of the first outer cover portion 910. Therefore, compared to the case where the thickness t2 of the second outer cover portion 920 is the same as the thickness t1 of the first outer cover portion 910, the attenuation of sound when it passes through the hole portion 921 can be reduced. Thus, the detection accuracy can be improved.

[0050] (3) In this embodiment, the Young's modulus of the first outer cover portion 910 is higher than that of the second outer cover portion 920. Therefore, compared to the case where the Young's modulus of the first outer cover portion 910 is the same as that of the second outer cover portion 920, impact resistance can be improved.

[0051] (Modified version of the third embodiment) A modified example of the third embodiment described above will now be explained. In the third embodiment described above, the cover portion 70 may not include the inner cover portion 80 and may consist only of the outer cover portion 90.

[0052] (Fourth Embodiment) A fourth embodiment will now be described. This embodiment is modified from the first embodiment by adding a discharge passage to the outer cover portion 90. Other aspects are the same as in the first embodiment, so a detailed explanation will be omitted here.

[0053] In this embodiment, the sound detection device S1 has a discharge passage 94 formed on the outer surface 90a of the outer cover portion 90, as shown in Figure 4. In this embodiment, the discharge passage 94 is a recess formed in a different part from the hole portion 91, and is formed to extend radially from the center of the outer cover portion 90 in the normal direction. Note that the hole portion 91 is omitted in Figure 4. In other words, in the normal direction, it can also be said to be viewed from the normal direction. In this embodiment, the discharge passage 94 corresponds to the discharge structure.

[0054] Furthermore, in this embodiment, as in the second embodiment described above, a situation in which water as a foreign substance may enter is assumed. The outer cover portion 90 has a water-repellent portion 93 formed in a different part from the discharge passage 94, similar to the second embodiment.

[0055] According to the embodiment described above, since the cover portion 70 has an outer cover portion 90 and an inner cover portion 80, the same effects as in the first embodiment can be obtained.

[0056] (1) In this embodiment, a discharge passage 94 is formed in the outer cover portion 90. Therefore, foreign matter can be easily discharged from the outer cover portion 90 through the discharge passage 94. For example, when the sound detection device S1 is positioned so that the connector case 20 is on the ground side in the vertical direction and the outer cover portion 90 is on the top side in the vertical direction, the foreign matter flows to the outer edge of the outer cover portion 90 and is discharged as shown by arrow A. In contrast, when the sound detection device S1 is positioned so that the connector case 20 is on the top side in the vertical direction and the outer cover portion 90 is on the ground side in the vertical direction, the foreign matter flows in the opposite direction to arrow A and is discharged by gathering at the center of the outer cover portion 90.

[0057] (2) In this embodiment, the outer cover portion 90 has a water-repellent portion 93 formed in a portion different from the discharge passage 94. Therefore, in situations where water as foreign matter can enter, foreign matter that reaches the outer cover portion 90 is more easily guided to the discharge passage 94 and discharged from the discharge passage 94. Thus, it is possible to suppress the entry of foreign matter into the interior of the outer cover portion 90.

[0058] (Modified version of the fourth embodiment) A modification of the fourth embodiment will now be described. In the fourth embodiment described above, if the sound detection device S1 is used in a situation in which oil as a foreign substance may enter, similar to the modification of the second embodiment described above, an oil-repellent portion may be formed instead of the water-repellent portion 93.

[0059] Furthermore, in the fourth embodiment described above, the water-repellent portion 93 may also be formed in the discharge passage 94. In other words, if the water-repellent portion 93 is formed, it is sufficient that it is formed in a portion different from the discharge passage 94.

[0060] Furthermore, in the fourth embodiment described above, the cover portion 70 may not include the inner cover portion 80 and may consist only of the outer cover portion 90. Also, in the fourth embodiment described above, the water-repellent portion 93 may not be formed. Even with such a sound detection device S1, foreign matter can be easily discharged from the discharge passage 94.

[0061] (Fifth embodiment) A fifth embodiment will now be described. This embodiment is a modification of the configuration of the outer cover portion 90 compared to the third embodiment. Other aspects are the same as in the third embodiment, so a detailed explanation will be omitted here.

[0062] As shown in Figure 5, the sound detection device S1 of this embodiment has an outer cover portion 90 which comprises a first outer cover portion 910 and a second outer cover portion 920. In this embodiment, the outer edge of the second outer cover portion 920 is configured to terminate inward from the outer edge of the first outer cover portion 910, and the outer edge is positioned away from one surface 51a of the bottom portion 51 of the lid portion 50. In other words, a predetermined gap G is formed between the outer edge of the second outer cover portion 920 and one surface 51a of the bottom portion 51 of the lid portion 50. Therefore, the hole 911 on the outer edge side of the first outer cover portion 910 is exposed from the second outer cover portion 920. In this embodiment, the shape of the second outer cover portion 920 corresponds to the discharge structure. Figure 5 corresponds to an enlarged view of region V in Figure 3.

[0063] Furthermore, in this embodiment, the lid portion 50 is configured to have a protrusion 53 and a stepped portion 54 as described above. The outer edge end of the second outer cover portion 920 is positioned opposite the stepped portion 54 in the normal direction, and the gap G between the stepped portion 54 and one surface 51a is shorter than the height of the protrusion 53. In other words, the outer edge end of the second outer cover portion 920 is positioned on the side of the stepped portion 54 than the virtual plane along one surface 51a of the protrusion 53. To put it another way, the outer edge end of the second outer cover portion 920 is positioned between the height of the portion of one surface 51a in which the through hole 55 is formed and the height of the portion of the first outer cover portion 910 that is assembled to the lid portion 50.

[0064] According to the embodiment described above, since the cover portion 70 has an outer cover portion 90 and an inner cover portion 80, the same effects as in the first embodiment can be obtained.

[0065] (1) In this embodiment, the second outer cover portion 920 is positioned such that its outer edge is separated from one surface 51a of the bottom portion 51 of the lid portion 50. Therefore, when foreign matter enters the inner surface 90b of the outer cover portion 90 and moves along the inner surface 90b to the outer edge, the foreign matter is transmitted from the second outer cover portion 920 to the first outer cover portion 910. Furthermore, the hole 911 of the first outer cover portion 910 is larger than the hole 921 of the second outer cover portion 920. Therefore, it is expected that foreign matter that reaches the first outer cover portion 910 will be discharged to the outer surface 90a of the first outer cover portion 910 through the hole 911. Thus, it is possible to suppress the accumulation of foreign matter inside the cover portion 70.

[0066] (2) In this embodiment, the lid portion 50 is configured to have a protrusion 53 and a stepped portion 54. The outer edge end of the second outer cover portion 920 is positioned opposite the stepped portion 54 in the normal direction, and the gap G between it and one surface 51a of the stepped portion 54 is shorter than the height of the protrusion 53. Therefore, it is possible to suppress foreign matter from reaching one surface 51a of the protrusion 53, and to further suppress it from reaching the sensor portion 40 through the through hole 55.

[0067] (Modified version of the fifth embodiment) A modified example of the fifth embodiment described above will now be explained. In the fifth embodiment described above, the cover portion 70 may not include the inner cover portion 80 and may consist only of the outer cover portion 90.

[0068] (Sixth Embodiment) A sixth embodiment will now be described. This embodiment does not include the inner cover portion 80 compared to the first embodiment. Other aspects are the same as the first embodiment, so a detailed explanation will be omitted here.

[0069] As shown in Figure 6, the sound detection device S1 of this embodiment does not have an inner cover portion 80. In other words, in this embodiment, the cover portion 70 is composed of the outer cover portion 90.

[0070] In such a sound detection device S1, if foreign matter enters the inner surface of the outer cover portion 90, the foreign matter may reach one surface 51a of the bottom portion 51 of the lid portion 50. However, in this embodiment, the bottom portion 51 is constructed with a convex portion 53 and a stepped portion 54. Therefore, if foreign matter reaches the bottom portion 51, as shown by arrow B in Figure 7, the foreign matter W flows towards the stepped portion 54, preventing it from accumulating near the through hole 55. Thus, it is possible to prevent foreign matter W from reaching the sensor portion 40 through the through hole 55. Note that Figure 7 omits the cover portion 70, etc. Also, in this embodiment, the shape of the bottom portion 51 corresponds to the discharge structure.

[0071] According to the embodiment described above, since the bottom portion 51 has a convex portion 53 and a stepped portion 54, it is possible to suppress foreign matter from reaching the sensor portion 40 through the through hole 55, and thus suppress a decrease in detection accuracy. This effect can also be obtained when there is an inner cover portion 80 as in the first embodiment described above.

[0072] (Modified version of the sixth embodiment) A modified example of the sixth embodiment described above will now be explained. In the sixth embodiment, the cover portion 70 may not include an outer cover portion 90, but may consist of an inner cover portion 80.

[0073] (Seventh Embodiment) The seventh embodiment will now be described. In this embodiment, a tapered portion is formed on the bottom 51 of the lid 50, compared to the sixth embodiment. Other aspects are the same as in the sixth embodiment, so their explanation will be omitted here.

[0074] As shown in Figure 8, the sound detection device S1 of this embodiment has a tapered shape on the bottom 51 of the lid 50, with the portion where the through hole 55 of the protrusion 53 is formed being used as the reference position, and one surface 51a approaching the connector case 20 side from the reference position toward the outer edge. In other words, the bottom 51 has the portion where the through hole 55 is formed being the most prominent, and one surface 51a slopes toward the connector case 20 side toward the outer edge from this portion toward the outer edge. Note that Figure 8 omits the cover portion 70 and the like. Also, in this embodiment, the shape of the bottom 51 corresponds to the discharge structure.

[0075] In such a sound detection device S1, if foreign matter enters the inner surface of the outer cover portion 90, the foreign matter may reach one surface 51a of the bottom portion 51 of the lid portion 50. However, in this embodiment, the bottom portion 51 is tapered, with the portion where the through hole 55 is formed being the reference position, and one surface 51a approaching the connector case 20 side from this reference position toward the outer edge. Therefore, if foreign matter reaches the bottom portion 51, as shown by arrow C in Figure 8, the foreign matter flows toward the outer edge end, thus preventing the foreign matter from reaching the sensor portion 40 through the through hole 55.

[0076] According to the embodiment described above, the bottom portion 51 has a tapered shape, with the portion where the through hole 55 is formed serving as the reference position, and one surface 51a approaching the connector case 20 side from this reference position toward the outer edge. Therefore, it is possible to suppress foreign matter from reaching the sensor portion 40 through the through hole 55, and thus suppress a decrease in detection accuracy.

[0077] (1) In this embodiment, the bottom portion 51 is tapered, with the portion where the through hole 55 is formed being the reference position, and one surface 51a approaching the connector case 20 side from this reference position toward the outer edge. Therefore, a decrease in detection accuracy due to reflection and diffraction of the bottom portion 51 can be suppressed. That is, as shown in Figure 9, when one surface 51a of the bottom portion 51 is tapered, compared to the case where one surface 51a is not tapered, as in Figure 7, for example, incident sound reaching the bottom portion 51 is reflected away from the through hole 55 at the bottom portion 51, becoming reflected sound. Therefore, the distance over which this reflected sound is reflected by the cover portion 70 and reaches the through hole 55 becomes longer, and it is more easily attenuated. Consequently, it becomes more difficult for the reflected sound to reach the sensor portion 40, and the influence of reflected sound is reduced. In addition, when incident sound reaches the bottom portion 51, diffraction sound is generated, but in this embodiment, compared to the case where one surface 51a is not tapered, as in Figure 7, for example, diffraction sound is less likely to penetrate the through hole 55. Therefore, the effects of diffraction sound are more easily reduced. As a result, the sound detection device S1 of this embodiment can further suppress the decrease in detection accuracy.

[0078] (Variation of the 7th embodiment) A modified example of the seventh embodiment described above will now be explained. In the seventh embodiment, the cover portion 70 may have an inner cover portion 80, similar to the first embodiment. Alternatively, in the seventh embodiment, the cover portion 70 may not have an outer cover portion 90 and may consist only of the inner cover portion 80.

[0079] (Eighth embodiment) The eighth embodiment will now be described. In this embodiment, guide holes are formed in the inner cover portion 80 compared to the first embodiment. Other aspects are the same as in the first embodiment, so a detailed explanation will be omitted here.

[0080] In the sound detection device S1 of this embodiment, as shown in Figure 10, a guide hole 83 is formed in the inner cover portion 80, penetrating between the outer surface 80a and the inner surface 80b. In this embodiment, the guide hole 83 is formed such that its axis coincides with the axis of the through hole 55. In other words, the guide hole 83 is formed directly above the through hole 55.

[0081] According to the embodiment described above, since the cover portion 70 has an outer cover portion 90 and an inner cover portion 80, the same effects as in the first embodiment can be obtained.

[0082] (1) In this embodiment, guide holes 83 are formed in the inner cover portion 80. Therefore, when sound passes through the inner cover portion 80, sound attenuation can be suppressed in the area of ​​the guide holes 83. Thus, detection accuracy can be improved. In addition, because sound attenuation can be suppressed in the area of ​​the guide holes 83, it is also possible to give directionality to the detection direction.

[0083] (Variation of the 8th embodiment) A modified example of the eighth embodiment will now be described. In the eighth embodiment, the portion in which the guide hole 83 is formed can be appropriately changed according to the direction in which direction directionality is desired. Also, in the eighth embodiment, the cover portion 70 may not have an outer cover portion 90, but may consist of an inner cover portion 80.

[0084] (Ninth Embodiment) The ninth embodiment will now be described. This embodiment is a modification of the configuration of the inner cover portion 80 compared to the first embodiment. Other aspects are the same as in the first embodiment, so their explanation will be omitted here.

[0085] In the sound detection device S1 of this embodiment, as shown in Figure 11, the inner cover portion 80 does not have a cavity formed on the inner surface 80b side. Furthermore, the inner cover portion 80 is positioned to abut against one surface 51a of the protrusion 53 and close the through hole 55. For this reason, in this embodiment, no internal space 100 is formed between the inner cover portion 80 and the lid portion 50. Also, since the inner cover portion 80 is positioned to close the through hole 55, a waterproof membrane 60 is not provided.

[0086] According to the embodiment described above, since the cover portion 70 has an outer cover portion 90 and an inner cover portion 80, the same effects as in the first embodiment can be obtained.

[0087] (1) In this embodiment, the inner cover portion 80 is positioned to be in contact with one surface 51a of the protrusion 53. As a result, a space is less likely to exist between the inner cover portion 80 and the protrusion 53, and sound scattering between the inner cover portion 80 and the protrusion 53 can be suppressed.

[0088] (Modified version of the 9th embodiment) A modified example of the ninth embodiment described above will now be explained. In the ninth embodiment, a waterproof membrane 60 may be provided. Also, in the ninth embodiment, the cover portion 70 may not have an outer cover portion 90, but may consist of an inner cover portion 80.

[0089] (Tenth embodiment) A tenth embodiment will now be described. This embodiment is similar to the first embodiment in that a filling member is placed inside. Other aspects are the same as the first embodiment, so a detailed explanation will be omitted here.

[0090] As shown in Figure 12, the sound detection device S1 of this embodiment has a filling member 120 made of gel or the like placed in the housing space 41 between the inner cover portion 80 and the connector case 20. However, the filling member 120 is placed in a portion of the sensor portion 40 that does not overlap with the through hole 55 in the normal direction. In other words, the filling member 120 is placed in a portion of the sensor portion 40 that is not easily exposed to sound through the through hole 55.

[0091] According to the embodiment described above, since the cover portion 70 has an outer cover portion 90 and an inner cover portion 80, the same effects as in the first embodiment can be obtained.

[0092] (1) In this embodiment, the filling member 120 is placed in the housing space 41 between the inner cover portion 80 and the connector case 20. This suppresses sound from entering the housing space 41 and suppresses sound reverberation within the housing space 41. Therefore, detection accuracy can be improved. The filling member 120 is placed in a portion of the sensor portion 40 that is different from the portion that overlaps with the through hole 55 in the normal direction. Therefore, the filling member 120 does not make it difficult for sound to be transmitted to the sensor portion 40.

[0093] (Modified version of the 10th embodiment) A modified example of the tenth embodiment described above will now be explained. In the tenth embodiment, the cover portion 70 may be composed of either an inner cover portion 80 or an outer cover portion 90.

[0094] (11th embodiment) The eleventh embodiment will now be described. This embodiment is similar to the first embodiment in that a protective member is added. Other aspects are the same as the first embodiment, so further explanation will be omitted here.

[0095] In this embodiment, as shown in Figure 13, the sound detection device S1 has a protective member 130 positioned where the lid 50 is crimped to the connector case 20. The protective member 130 is made of, for example, potting resin.

[0096] According to the embodiment described above, since the cover portion 70 has an outer cover portion 90 and an inner cover portion 80, the same effects as in the first embodiment can be obtained.

[0097] (1) In this embodiment, a protective member 130 is placed in the portion where the lid 50 is crimped to the connector case 20. This prevents foreign matter from entering between the connector case 20 and the lid 50, and prevents excessive stress from being generated in the crimped portion. Therefore, the lifespan of the sound detection device S1 can be extended.

[0098] (Modified version of the 11th embodiment) A modified example of the 11th embodiment described above will now be explained. In the 11th embodiment described above, the cover portion 70 may be composed of either an inner cover portion 80 or an outer cover portion 90.

[0099] (12th embodiment) A twelfth embodiment will now be described. This embodiment differs from the first embodiment in that the shape of the connector case 20 is changed and mounting members are added. Other aspects are the same as in the first embodiment, so a detailed explanation will be omitted here.

[0100] As shown in Figure 14, the sound detection device S1 of this embodiment has a flared shape in the second portion 22 of the connector case 20, which widens from the side of the first portion 21 toward the opposite side. In other words, in a cross-section along the axial direction, the second portion 22 of the connector case 20 has a tapered shape in which the length of the opposing side surfaces gradually increases from the side of the first portion 21 toward the opposite side.

[0101] Furthermore, the sound detection device S1 has a magnet 140 as a mounting member positioned at the other end of the second part 22 opposite to the first part 21 side.

[0102] According to the embodiment described above, since the cover portion 70 has an outer cover portion 90 and an inner cover portion 80, the same effects as in the first embodiment can be obtained.

[0103] (1) In this embodiment, the second portion 22 of the connector case 20 has a flared shape that widens from the first portion 21 side toward the opposite side. Therefore, when attaching the sound detection device S1 to a mounting member such as a machine tool, the mounting area can be widened, making attachment easier. Furthermore, in this embodiment, a magnet 140 as an attachment member is also arranged at the other end of the second portion 22. Therefore, if the mounting location of the mounting member is made of metal or the like, the sound detection device S1 can be easily attached by the magnet 140. In other words, the sound detection device S1 of this embodiment can improve the ease of attachment to the mounting member.

[0104] (Modified version of the 12th embodiment) A modified example of the 12th embodiment described above will now be explained. In the 12th embodiment described above, the cover portion 70 may be composed of either an inner cover portion 80 or an outer cover portion 90.

[0105] (13th Embodiment) A thirteenth embodiment will now be described. This embodiment adds a control unit to the first embodiment. Other aspects are the same as the first embodiment, so their explanation will be omitted here.

[0106] As shown in Figure 15, the sound detection device S1 of this embodiment is equipped with a control unit 200 connected to a sensor unit 40 via a terminal 27 or the like. The control unit 200 is composed of a microcomputer or the like, which includes a CPU and a storage unit composed of non-transitional physical storage media such as ROM, RAM, flash memory, and HDD. Note that CPU is an abbreviation for Central Processing Unit, ROM is an abbreviation for Read Only Memory, RAM is an abbreviation for Random Access Memory, and HDD is an abbreviation for Hard Disk Drive.

[0107] The control unit 200 then performs various control operations by having the CPU read and execute programs (i.e., the routines described later) from a storage unit such as ROM. The storage unit such as ROM pre-stores various data used when executing programs (for example, initial values, lookup tables, maps, etc.).

[0108] Specifically, when the control unit 200 is installed in a machine tool as a component to be mounted, it performs an abnormality determination of the machine tool based on the detection signal detected by the sensor unit 40. The control unit 200 also performs a self-diagnosis determination of the sensor unit 40 based on the detection signal detected by the sensor unit 40. For example, if a foreign object enters the sensor unit 40 of the sound detection device S1 or if damage occurs due to mechanical stress, the detection signal will change even if the machine tool is not in operation. Therefore, in this embodiment, for example, a self-diagnosis determination is performed based on the detection signal when the machine tool is not in operation. The control unit 200 is connected to a notification unit (not shown) and transmits a determination signal indicating the determination result to the notification unit. As a result, the notification unit notifies the operator of the content corresponding to the determination signal.

[0109] According to the embodiment described above, since the cover portion 70 has an outer cover portion 90 and an inner cover portion 80, the same effects as in the first embodiment can be obtained.

[0110] (1) In this embodiment, a control unit 200 is provided, which performs self-diagnosis and determination of the sensor unit 40. Therefore, it is possible to suppress the determination of abnormality of the machine tool when the sound detection device S1 is abnormal.

[0111] (2) In this embodiment, the control unit 200 is located on the outside of the case 10. Therefore, it is easy to change the control of the control unit 200 depending on the application.

[0112] (Modified version of the 13th embodiment) A modified example of the 13th embodiment described above will now be explained. In the 13th embodiment described above, the cover portion 70 may be composed of either an inner cover portion 80 or an outer cover portion 90.

[0113] Furthermore, the control unit 200 may not be located outside the case 10, but may be incorporated into the wiring board 30, for example. This allows for a smaller sound detection device S1 compared to the case where the control unit 200 is externally mounted.

[0114] (Other embodiments) This disclosure is described in accordance with embodiments, but it is understood that this disclosure is not limited to such embodiments or structures. This disclosure also includes various modifications and variations within the scope of equivalents. In addition, various combinations and forms, as well as other combinations and forms that include only one, more, or fewer of those elements, fall within the scope and idea of ​​this disclosure.

[0115] In each of the above embodiments, the configuration of the case 10 can be changed as appropriate. For example, in the first embodiment, the case 10 may be made up of a connector case 20, and the inner cover portion 80 and the outer cover portion 90 may be fixed to the connector case 20.

[0116] Furthermore, in each of the above embodiments, for example, in the first embodiment, the bottom portion 51 may not have a protrusion 53 formed on it, and one surface 51a may be flat.

[0117] Furthermore, in each of the above embodiments, the wiring board 30 may not be provided, and the sensor unit 40 may be directly connected to the terminal 27 or the like.

[0118] Furthermore, the above embodiments can be combined as appropriate. For example, the second embodiment may be combined as appropriate to include water-repellent parts 82 and 93. The third embodiment may be combined as appropriate to configure the outer cover part 90 with a first outer cover part 910 and a second outer cover part 920. The fourth embodiment may be combined as appropriate to include a discharge passage 94. The fifth embodiment may be combined as appropriate to have a first outer cover part 910 and a second outer cover part 920, and the positional relationship of the second outer cover part 920 may be adjusted. The sixth embodiment may be combined as appropriate to configure the cover part 70 with the outer cover part 90. The seventh embodiment may be combined as appropriate to make one surface 51a of the lid part 50 tapered. The eighth embodiment may be combined as appropriate to form a guide hole 83 in the inner cover part 80. The ninth embodiment may be combined as appropriate to make the inner cover part 80 in contact with one surface 51a around the through hole 55. The tenth embodiment may be combined as appropriate to include a filling member 120. The 11th embodiment described above may be combined as appropriate to include the protective member 130. The 12th embodiment described above may be combined as appropriate to make the second portion 22 flared outwards and include the magnet 140. The 13th embodiment described above may be combined as appropriate to include the control unit 200.

[0119] The control unit and its method described herein may be implemented by a dedicated computer provided by configuring a processor and memory programmed to perform one or more functions embodied by a computer program. Alternatively, the control unit and its method described herein may be implemented by a dedicated computer provided by configuring a processor by one or more dedicated hardware logic circuits. Alternatively, the control unit and its method described herein may be implemented by one or more dedicated computers configured by a combination of a processor and memory programmed to perform one or more functions and a processor configured by one or more hardware logic circuits. Furthermore, the computer program may be stored as instructions executed by the computer on a computer-readable non-transitional tangible recording medium.

[0120] [Disclosure of the Invention] The above disclosure can be understood from the following perspectives, for example. [First point of view] A sound detection device, A sensor unit (40) that outputs a detection signal corresponding to sound, The case (10) in which the sensor unit is arranged, The case is assembled to a cover portion (70) that protects the sensor portion, The cover portion has an inner cover portion (80) positioned on the sensor portion side, and an outer cover portion (90) positioned on the opposite side of the sensor portion, sandwiching the inner cover portion, and covering the inner cover portion. The inner cover portion is composed of a windscreen member made of a porous material. The sound detection device is characterized in that the outer cover portion is made of a hard material with a higher Young's modulus than the inner cover portion, and a plurality of holes (91) are formed that penetrate between the inner surface (90b) located on the inner cover portion side and the outer surface (90a) on the opposite side of the inner surface.

[0121] [Second perspective] The sound detection device according to the first aspect, wherein the outer cover portion and the inner cover portion are arranged such that a predetermined space (110) is formed between the outer cover portion and the inner cover portion.

[0122] [Third perspective] The sound detection device according to the first or second aspect, wherein at least one of the outer cover portion and the inner cover portion has a water-repellent portion (82, 93) or an oil-repellent portion formed thereon.

[0123] [Fourth perspective] The outer cover portion is formed by joining a first outer cover portion (910) having a hole (911) and a second outer cover portion (920) having a hole (921), and the hole portion of the outer cover portion is formed in the portion where the hole portion of the first outer cover portion and the hole portion of the second outer cover portion communicate with each other. The first outer cover portion and the second outer cover portion are arranged such that the second outer cover portion is positioned on the side of the inner cover portion. The sound detection device according to any one of the first to third views, wherein the hole formed in the second outer cover portion has a smaller opening size than the hole formed in the first outer cover portion.

[0124] [Fifth perspective] The sound detection device according to the fourth aspect, wherein the second outer cover portion has a thickness (t2) that is thinner than the thickness (t1) of the first outer cover portion.

[0125] [Sixth perspective] The sound detection device according to any one of the first to fifth views, wherein the inner cover portion has an induction hole (83) formed through the inner cover portion.

[0126] [Perspective 7] The sound detection device according to any one of the first to sixth views, wherein at least one of the case and the cover portion is provided with a discharge structure (50, 94, 920) for discharging foreign matter.

[0127] [Perspective 8] The sound detection device according to the seventh aspect, wherein the discharge structure is a discharge passage (94) formed on the outer surface of the outer cover portion that serves as a passage for foreign matter.

[0128] [Perspective 9] The sound detection device according to the eighth aspect, wherein the outer cover portion has a water-repellent portion (93) or an oil-repellent portion formed on its outer surface in a portion different from the discharge passage.

[0129] [Perspective 10] The case comprises a connector case (20) having a recess (24) formed therein, and a lid (50) having a bottom (51) with one surface (51a) and another surface (51b) opposite to the one surface, the other surface facing the bottom surface of the recess, and the bottom being assembled to the connector case such that it closes the recess of the connector case, thereby forming a housing space (41) between the case and the lid. The aforementioned detection unit is arranged in the aforementioned containment space. The sound detection device according to any one of the seventh to ninth views, wherein the cover portion has a through hole (55) formed in the portion facing the sensor portion.

[0130] [Perspective 11] A sound detection device according to the tenth aspect, comprising a porous material and having a protective membrane (60) arranged to close the through-holes.

[0131] [Perspective 12] The outer cover portion is formed by joining a first outer cover portion (910) having a hole (911) and a second outer cover portion (920) having a hole (921), and the hole portion of the outer cover portion is formed in the portion where the hole portion of the first outer cover portion and the hole portion of the second outer cover portion communicate with each other. The holes formed in the second outer cover portion have smaller openings than the holes formed in the first outer cover portion. The first outer cover portion and the second outer cover portion are integrated such that the second outer cover portion is positioned on the side of the inner cover portion, and the outer edge of the first outer cover portion is exposed from the second outer cover portion. The first outer cover portion has an outer edge end that is exposed from the second outer cover portion and is assembled to the lid portion. The sound detection device according to the tenth or eleventh aspect, wherein the second outer cover portion is positioned away from the lid portion as the discharge structure.

[0132] [Perspective 13] The sound detection device according to the twelfth view, wherein the outer edge of the second outer cover portion is located between the height of the portion of the surface in which the through hole is formed and the height of the portion of the first outer cover portion that is assembled to the lid portion.

[0133] [Perspective 14] The lid portion has a protrusion (53) formed on the bottom portion opposite to the sensor portion, which serves as the discharge structure, and a stepped portion (54) formed on the bottom portion that is different from the protrusion, and the through hole is formed in the protrusion. The sound detection device according to any one of the 10th to 13th views, wherein a portion of the sensor portion is arranged in the space within the protrusion.

[0134] [Perspective 15] The sound detection device according to any one of the 10th to 13th views, wherein one surface of the lid is tapered, with the portion where the through hole is formed being the reference position, and the tapered shape increases as it moves from the reference position toward the outer edge end.

[0135] [Perspective 16] The sound detection device according to any one of the 10th to 14th views, wherein the inner cover portion is arranged to abut against one surface of the lid portion and closes the opening of the through hole on the one surface side. [Explanation of Symbols]

[0136] 10 cases 40 Sensor section 70 Cover section 80 Inner cover section 90 Outer cover section 90a Inner surface 90b External surface 91 Hole

Claims

1. A sound detection device, A sensor unit (40) that outputs a detection signal corresponding to sound, The case (10) in which the sensor unit is arranged, The case is assembled to a cover portion (70) that protects the sensor portion, The cover portion has an inner cover portion (80) positioned on the sensor portion side, and an outer cover portion (90) positioned on the opposite side of the sensor portion, sandwiching the inner cover portion, and covering the inner cover portion. The inner cover portion is composed of a windscreen member made of a porous material. The sound detection device is characterized in that the outer cover portion is made of a hard material with a higher Young's modulus than the inner cover portion, and a plurality of holes (91) are formed that penetrate between the inner surface (90b) located on the inner cover portion side and the outer surface (90a) on the opposite side of the inner surface.

2. The sound detection device according to claim 1, wherein the outer cover portion and the inner cover portion are arranged such that a predetermined space (110) is formed between the outer cover portion and the inner cover portion.

3. The sound detection device according to claim 1, wherein at least one of the outer cover portion and the inner cover portion has a water-repellent portion (82, 93) or an oil-repellent portion formed thereon.

4. The outer cover portion is formed by joining a first outer cover portion (910) having a hole (911) and a second outer cover portion (920) having a hole (921), and the hole portion of the outer cover portion is formed in the portion where the hole portion of the first outer cover portion and the hole portion of the second outer cover portion communicate with each other. The first outer cover portion and the second outer cover portion are arranged such that the second outer cover portion is positioned on the side of the inner cover portion. The sound detection device according to claim 1, wherein the hole formed in the second outer cover is smaller in size than the hole formed in the first outer cover.

5. The sound detection device according to claim 4, wherein the second outer cover portion has a thickness (t2) that is thinner than the thickness (t1) of the first outer cover portion.

6. The sound detection device according to claim 1, wherein the inner cover portion has an induction hole (83) that penetrates the inner cover portion.

7. The sound detection device according to claim 1, wherein at least one of the case and the cover portion has a discharge structure (50, 94, 920) for discharging foreign matter.

8. The sound detection device according to claim 7, wherein the discharge structure is a discharge passage (94) formed on the outer surface of the outer cover portion that serves as a passage for foreign matter.

9. The sound detection device according to claim 8, wherein the outer cover portion has a water-repellent portion (93) or an oil-repellent portion formed on its outer surface in a portion different from the discharge passage.

10. The case comprises a connector case (20) having a recess (24) formed therein, and a lid (50) having a bottom (51) with one surface (51a) and another surface (51b) opposite to the one surface, the other surface facing the bottom surface of the recess, and the bottom being assembled to the connector case such that it closes the recess of the connector case, thereby forming a storage space (41) between the case and the lid. The aforementioned detection unit is arranged in the aforementioned containment space. The sound detection device according to any one of claims 7 to 9, wherein the lid portion has a through hole (55) formed in the portion facing the sensor portion.

11. The sound detection device according to claim 10, comprising a porous material and a protective membrane (60) arranged to close the through-hole.

12. The outer cover portion is formed by joining a first outer cover portion (910) having a hole (911) and a second outer cover portion (920) having a hole (921), and the hole portion of the outer cover portion is formed in the portion where the hole portion of the first outer cover portion and the hole portion of the second outer cover portion communicate with each other. The holes formed in the second outer cover portion have smaller openings than the holes formed in the first outer cover portion. The first outer cover portion and the second outer cover portion are integrated such that the second outer cover portion is positioned on the side of the inner cover portion, and the outer edge of the first outer cover portion is exposed from the second outer cover portion. The first outer cover portion has an outer edge end that is exposed from the second outer cover portion and is assembled to the lid portion. The sound detection device according to claim 10, wherein the second outer cover portion is positioned as the discharge structure, with its outer edge portion separated from the lid portion.

13. The sound detection device according to claim 12, wherein the outer edge of the second outer cover portion is located between the height of the portion of the surface in which the through hole is formed and the height of the portion of the first outer cover portion that is assembled to the lid portion.

14. The lid portion has a protrusion (53) formed on the bottom portion opposite to the sensor portion, which serves as the discharge structure, and a stepped portion (54) formed on the bottom portion that is different from the protrusion, and the through hole is formed in the protrusion. The sound detection device according to claim 10, wherein a portion of the sensor portion is arranged in the space within the protrusion.

15. The sound detection device according to claim 10, wherein one surface of the lid is tapered, and as the discharge structure, with the portion where the through hole is formed being the reference position, the surface tapers closer to the connector case side as it moves from the reference position toward the outer edge end.

16. The sound detection device according to claim 10, wherein the inner cover portion is arranged to abut against one surface of the lid portion and closes the opening of the through hole on the one surface side.

Images