JP5618788B2 - Sound absorbing material mounting structure - Google Patents

Description

The present invention relates to a sound absorbing material mounting structure for attaching a sound absorbing material to a ventilation path through which a gas such as air flows. In particular, the present invention relates to a sound absorbing material mounting structure in which a sound absorbing material is fixed to an inner peripheral surface of a member constituting a part of a ventilation path to reduce noise propagating in the ventilation path.

In various fields such as supply of air to an internal combustion engine, air blowing in an air cooling device, an air conditioner, and the like, a ventilation path is constituted by a duct member and the like, and air is sent through the ventilation path. In recent years, these ventilation paths are used not only in the intake system of internal combustion engines of automobiles, but also in cooling air blowing systems for cooling secondary batteries (storage batteries) provided in fuel cell vehicles and electric vehicles. It has been used widely. Since these ventilation paths often serve as noise transmission paths, in the configuration of these ventilation paths, fiber aggregates and synthetic resin foam are formed on the ducts forming the air flow paths and the inner surface of the expanded chamber portion. It is possible to reduce the noise over a relatively wide frequency range by attaching a sound-absorbing material made of a material (so-called sponge) and configuring it as a so-called sound-absorbing duct to absorb the acoustic energy of noise propagating in the ventilation path. Has been done.

In such a sound absorbing duct, various structures are known for attaching a sound absorbing material to the inner peripheral surface of the ventilation path. For example, Patent Document 1 describes a sound-absorbing material attached to the inner surface of a duct, and Patent Document 2 forms a duct by opposing and connecting bowl-shaped duct members. A sound absorbing material mounting structure is described in which a sound absorbing material arranged in a duct member is pressed and fixed at the tip of a holding plate (rib) formed integrally with the other duct member and parallel to the duct axial direction. Yes. In addition, as a structure for fixing the sound absorbing material in the duct, a structure using an adhesive or a double-sided tape, a structure in which the sound absorbing material is filled in a predetermined space, or a sound absorbing material for these members using a pin member or a claw member There are known structures for locking and mounting. For example, Patent Document 3 discloses that a sound absorbing material is passed through a boss standing on a cover member and the sound absorbing material is fixed by caulking the tip of the boss.

JP-A-11-117761 JP 09-49417 A Jissen-Benbun 02-85863

In order to attach the sound absorbing material inside the ventilation path, it is necessary to prevent the sound absorbing material from being displaced or turned up by the air current so as not to disturb the air flow inside the ventilation path. For this reason, many pins and claws for fixing the sound absorbing material are required, and the work of attaching the sound absorbing material tends to be complicated. In particular, the mounting structure using caulking as disclosed in Patent Document 3 involves a step of caulking by a mechanical means or an ultrasonic welding machine after the sound absorbing material is arranged in the mounting step of the sound absorbing material. For this reason, the work of attaching the sound absorbing material tends to be complicated.
Further, since it is necessary to use a plate-like member such as a washer or a plate-like member for the caulking portion, the surface area at which the sound absorbing material is exposed may be reduced, and the silencing effect may be insufficient.

In addition, if the sound absorbing material is attached using an adhesive or adhesive, the sound absorbing material may be wrinkled or sound absorbing, particularly when a large sound absorbing material is attached along a recess in the ventilation path. In many cases, it is difficult to adjust the mounting position of the material, which makes the mounting work difficult.

Therefore, the object of the present invention is to use a fixing structure different from the conventionally known sound absorbing material fixing structure, and to easily maintain the mounting state of the sound absorbing material, while the sound absorbing material can be easily attached. It is to provide a mounting structure.

The inventors have studied to lock and fix a sponge sound absorbing material made of a resin foam material (for example, urethane sponge) as a sound absorbing material and having a substantially flat elasticity to a member constituting the ventilation path. As shown schematically in FIG. 9, the sound absorbing material fixing structure for fixing the sound absorbing material by locking the peripheral edge portion of the sponge sound absorbing material 4 with a claw member 91 integrally formed with the ventilation path constituting member 9 is examined. went. According to this sound absorbing material mounting structure, the mounting is completed simply by hooking the sound absorbing material peripheral portion to the claw member 91 using the elasticity of the sound absorbing material, and the sound absorbing material can be easily mounted.

However, when such a sound absorbing material mounting structure is applied to a part that is directly exposed to an air flow during further investigation, depending on the flow velocity of the air flow, the locking by the claw member 91 may be released and the sound absorbing material may be peeled off. I knew that there was.

The inventors conducted further experiments and studied the reason why the claw member is unlocked. As a result, it was found that the claw member 91 can be easily unlocked by the following mechanism. That is, as shown in FIG. 10, when an air flow flows along the surface of the sound absorbing material, dynamic pressure (negative pressure) is generated by the air flow, and due to this negative pressure fluctuation and a pressure difference between the front side and the back side of the sound absorbing material. It was found that the center portion of the sound absorbing material 4 that is not locked is deformed so as to be lifted. It has also been found that the sound absorbing material is significantly lifted up by the air current blowing on the surface of the sound absorbing material that is slightly lifted. In this way, when the sound absorbing material is lifted, the peripheral portion of the sound absorbing material is pulled out from directly below the claw member 91, and the claw member is not sufficiently locked and the sound absorbing material is detached. It becomes easier.

That is, the inventors do not lie in the cause that the sound absorbing material comes off, because the locking strength in the direction perpendicular to the sound absorbing material mounting surface (perpendicular direction) is insufficient, near the claw member, It has been found that the sound absorbing material is displaced in the horizontal direction (in-plane direction) with respect to the sound absorbing material mounting surface due to the air flow, and the claw member is not sufficiently locked.

The inventors have found that the reliability of the sound absorbing material can be improved by suppressing the horizontal shift, and have completed the present invention.

The present invention relates to a sound absorbing material mounting structure in which a rectangular and flat sound absorbing material made of a resin foam material is mounted on a mounting region provided on an inner peripheral surface of a member that constitutes a part of a ventilation path. A locking claw that is provided at the periphery of the material and that locks the sound absorbing material without penetrating the sound absorbing material to hold the sound absorbing material in a direction perpendicular to the mounting area surface, and in a direction that penetrates the sound absorbing material in the vicinity of the locking claw provided by by the projecting member for regulating a mounting region surface in the direction of movement of the sound absorbing material, and one side of the peripheral portion of at least the sound absorbing material is fixed, and, in the sides, the locking claw is of the side extension A plurality of sound absorbers are provided so as to be spaced apart from each other in the existing direction, and in the positional relationship in the extending direction of the side, the position where the projecting member is provided is a sound absorbing material mounting structure in the middle of adjacent locking claws. Yes (first invention).

In the conventional mounting structure, the sound-absorbing material mounting strength has been improved mainly by improving the holding force in the direction perpendicular to the mounting area surface by the locking member. And it was thought that the locking member that can be held in the in-plane direction of the attachment region does not contribute to the holding force in the direction perpendicular to the surface. However, in the present invention, the engaging claws that are held in the direction perpendicular to the mounting area surface are combined with a projecting member that restricts the movement in the mounting area surface direction, and their synergistic effect results in an unexpected increase in holding force. It is.

Further, in the present invention, the protruding member is a member that extends in the direction perpendicular to the surface of the attachment region and penetrates the sound absorbing material, and the protruding member substantially places the sound absorbing material in the direction perpendicular to the attachment region surface. It is preferable not to hold ( second invention).

Moreover, in this invention, it is preferable that a protrusion member is spaced apart and provided from a latching claw, and the separation distance between both is made into 1 time-10 times the thickness dimension of a sound-absorbing material ( 3rd invention).

According to the present invention (the first invention), the peripheral portion of the sound absorbing material is locked to the peripheral edge of the sound absorbing material to hold the sound absorbing material in the direction perpendicular to the attachment region surface, and the sound absorbing material is located in the vicinity of the locking claw. Since the sound absorbing material is fixed by a projecting member that restricts the movement of the sound absorbing material in the in-plane direction of the mounting area, the sound absorbing material is applied to the locking claws and the projecting member using the elasticity of the sound absorbing material. The sound absorbing material can be fixed by being hooked, and the mounting work of the sound absorbing material is simple.

And since the sound absorbing material peripheral portion is fixed by a combination of a locking claw that holds the sound absorbing material in the direction perpendicular to the mounting region surface and a protruding member that restricts the movement of the sound absorbing material in the mounting region surface direction, Even if the sound absorbing material floats up and is about to be pulled out, the protruding member prevents the sound absorbing material peripheral portion from being pulled out from the locking claw, and the retention force by the locking claw can be maintained, so that the ventilation environment can be maintained. The mounted state of the sound absorbing material can be properly maintained.

Further, in the present invention, a plurality of locking claws are provided on the fixed side so as to be separated from each other in the extending direction of the side, and the protruding member is provided in the positional relationship in the extending direction of the side. Since the position where the sound absorbing material is positioned is between the adjacent locking claws, the operation of elastically deforming the sound absorbing material peripheral portion and locking it to the locking claws is not obstructed by the protruding member, and the sound absorbing material mounting work is Especially simple.

Further, in the case of the second invention, the efficiency of the work of fixing the sound absorbing material by passing the protruding member through the sound absorbing material while reliably exhibiting the restraining effect in the in-plane direction of the protruding member. Can be increased.

Furthermore, in the case of the third invention, the mounting operation of the sound absorbing material is remarkably simplified and the mounting state of the sound absorbing material becomes more reliable.

It is a disassembled perspective view of the sound absorption duct to which the first embodiment of the present invention is applied. It is a perspective view which shows the shape of the lower case and sound-absorbing material in 1st Embodiment. It is XX sectional drawing of the sound-absorbing material and lower case in 1st Embodiment. It is a YY sectional view of a sound absorbing material and a lower case in the first embodiment. It is the figure which looked at the sound-absorbing material and lower case in 1st Embodiment from the attachment area | region surface direct direction. It is a figure which shows the other example of a shape of the latching claw in 1st Embodiment. It is sectional drawing of the decomposition | disassembly state of the air cleaner to which 2nd Embodiment of this invention was applied. It is a figure which shows embodiment of the other arrangement | positioning of the latching claw and projection member in this invention. It is a figure which shows the example of the sound-absorbing-material attachment structure by a prior art. It is a figure which shows the condition where the sound absorption material deform | transformed and became easy to remove | deviate in a prior art. It is a perspective view which shows the lower case which has the protrusion member of another shape in this invention. It is a perspective view which shows the other example of a shape of the sound-absorbing material in this invention. It is the figure which looked at the sound-absorbing material and lower case of embodiment which used the other locking member together in this invention from the attachment area | region surface direct direction.

Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. In addition, this invention is not limited to the separate embodiment shown below, The form can also be changed and implemented. 1 to 5 show an example of a sound absorbing duct in which the sound absorbing material mounting structure of the present invention is applied to a blower duct used for blowing cooling air for cooling a secondary battery of a hybrid vehicle.
FIG. 1 is an exploded perspective view showing the overall structure of the sound absorbing duct, and FIG. 2 is a perspective view of the duct lower case alone and the sound absorbing material. 3 is a cross-sectional view (XX cross-sectional view) in a plane along the axial direction of the duct of the portion where the sound absorbing material is disposed, and FIG. 4 is a duct of the portion where the sound absorbing material is disposed. It is sectional drawing in the plane orthogonal to the axial direction of (YY sectional drawing). FIG. 5 is a view of the lower case and the sound absorbing material viewed from the direction perpendicular to the sound absorbing material mounting surface.

The sound absorbing duct 1 is configured by integrally assembling two case members, an upper case 2 and a lower case 3, which are half-cracked along the duct path, and the internal space is a hollow cooling air ventilation path. FIG. 1 is an exploded view showing a state before the upper case 2 and the lower case 3 are integrated. In the secondary battery air cooling system, the sound absorbing duct 1 is used as a part of a series of ventilation paths by connecting an air intake port, a blower fan, a battery case, other duct members, and the like before and after the sound absorbing duct 1.

The upper case 2 and the lower case 3 are resin molded products formed by injection molding of a thermoplastic synthetic resin (polypropylene resin in the present embodiment), and the side edges of each other are bonded, welded, engaged, etc. Thus, the sound absorbing duct 1 is formed. In the present embodiment, the upper case 2 and the lower case 3 are both formed in a bowl shape having a substantially U-shaped cross section. In the present embodiment, both the upper case 2 and the lower case 3 are formed in substantially symmetrical shapes, and the sound absorbing material 4 is attached inside the upper case 2 and the lower case 3, so in the following description, the structure for mounting the sound absorbing material to the lower case The explanation will be focused on.

As shown in FIG. 2, the lower case 3 is formed in a bowl-like shape in which both end portions 30 and the whole define a ventilation path of the duct, and the lower wall 3 has a peripheral wall (on the lower surface side) at the center of the duct. The bulging part 31 provided so that a surrounding wall may protrude toward the duct lower side is formed. The sound absorbing material 4 is attached to the inside of the bulging portion 31. That is, in the present embodiment, the inner peripheral surface 31a on the lower side of the duct of the bulging portion 31 is an attachment region S where the sound absorbing material 4 is to be attached.

The part to which the sound absorbing material 4 is attached will be described in detail. In the present embodiment, the attachment region S to which the sound absorbing material 4 is to be attached is an inner peripheral surface 31a on the lower side of the bulging portion 31, which corresponds to the bottom surface of the bulging portion and is a substantially flat mounting surface. ing. The attachment region S has a rectangular shape. The depth of the bulging portion 31 (the amount of protrusion to the lower side of the duct compared to the duct end portion 30) is the same size as that of the sound absorbing material 4, and both ends of the lower case with the sound absorbing material 4 attached. The inner peripheral surface of the part 30 and the surface of the sound absorbing material 4 are connected almost smoothly.

The sound-absorbing material 4 attached to the attachment region S is an elastic sound-absorbing material made of a resin foam material (foamed urethane sponge or the like) and is formed so as to have a substantially flat plate shape in an unloaded state. The sound absorbing material 4 is formed in a flat plate shape that substantially matches the mounting region S, and is attached to the mounting region S so that the bulging portion 31 is filled with the sound absorbing material 4.

The sound absorbing material 4 is fixed as follows.
Locking claws 32 and 32 are provided along the periphery of the bulging portion 31 of the lower case 3, that is, along the periphery of the attachment region S. In the present embodiment, the locking claws 32, 32 are arranged at the corner portion of the rectangular attachment region S and at substantially the center of the side where the rectangular attachment region S faces the case end portions 30. . Furthermore, the locking claw 32 has a shape extending substantially parallel to the mounting surface 31a in the direction from the sound absorbing material peripheral edge toward the inside of the sound absorbing material so as to extend the bottom surface of the case both end portions 30 along the duct axial direction. The edge of the sound absorbing material 4 is arranged in the space between the locking claw 32 and the mounting surface 31a, and the sound absorbing material 4 is sandwiched between the locking claw 32 and the mounting surface 31a. The peripheral edge of the sound absorbing material 4 is held in the direction perpendicular to the attachment region S by the locking claws 32. It is preferable that the sound absorbing material 4 is sandwiched between the locking claw 32 and the mounting surface 31a so that the sound absorbing material is slightly compressed between them in order to secure the sound absorbing material. The degree of clamping may be such that the sound absorbing material can be prevented from moving in the direction perpendicular to the mounting surface by the locking claws, and the sound absorbing material does not necessarily need to be compressed. There may be a gap between the sound absorbing material and the locking claw.

Further, tapered pin-shaped projecting members 33 and 33 are provided from the mounting surface 31 a of the lower case 3, that is, the sound absorbing material mounting region S. The protruding member 33 is provided so as to extend substantially perpendicular to the mounting surface 31 a so as to penetrate the sound absorbing material 4. The sound absorbing material 4 is provided with through holes 41, 41 corresponding to the positions of the protruding members 33, and the protruding members 33, 33 are provided through the sound absorbing material through the through holes 41, 41, The movement of the sound absorbing material 4 in the in-plane direction with respect to the attachment region S is limited / restricted by the member 33. In the present embodiment, the protruding member 33 is only in light contact with the sound absorbing material 4 and has substantially no force to hold the sound absorbing material in the direction perpendicular to the mounting region surface of the sound absorbing material.

The protruding member 33 is provided in the vicinity of the locking claw 32. Assuming that the thickness of the resin foam material constituting the sound absorbing material 4 is d, the separation distance W (W is shown in FIG. 5) between the protruding member 33 and the locking claw 32 when viewed from the direction perpendicular to the mounting region S, It is preferable to satisfy d <W <10 * d, and it is particularly preferable to satisfy 2 * <W <5 * d. When the separation distance W is reduced, the workability of the mounting operation of the sound absorbing material 4 is lowered, and when the separation distance W is increased, the certainty of holding the sound absorbing material is easily impaired.

Further, in the present embodiment, in the positional relationship in the direction along the periphery of the sound absorbing material 4, the protrusion member 33 is particularly preferably at the middle position between the positions where the locking claws 32, 32 are provided. Provided in position.
In the present embodiment, a locking claw and a projecting member are provided on the side of the peripheral edge of the sound absorbing material on the side where the rectangular attachment region S faces the case both ends 30. The entire periphery of the periphery of the sound absorbing material may be fixed with such a fixing structure, or only a part of the periphery may be fixed as in this embodiment.

The work of attaching the sound absorbing material 4 to the lower case 3 can be performed using the elasticity of the sound absorbing material. That is, with respect to the lower case 3 and the locking claws 32, 32 and the protruding members 33, 33 formed by means such as injection molding, the sound absorbing material 4 formed in a predetermined size is placed inside the bulging portion 31, that is, the attachment region. The sound absorbing material 4 is placed on the S, elastically deforming the sound absorbing material, and the projecting members 33 and 33 are passed through the through holes 41 and 41 of the sound absorbing material 4, while the peripheral portion of the sound absorbing material 4 is below the locking claws 32 and 32. The attachment of the sound-absorbing material 4 is completed by pushing and engaging. If necessary, other attachment members such as a locking claw member, a pin member, and an adhesive tape provided in other parts can be used in combination. In particular, when the sound absorbing material is large, it is preferable to provide these other mounting members at the center of the sound absorbing material.

When the attachment of the sound absorbing material is completed, the sound absorbing material 4 returns to a shape that fills the bulging portion 31 by the restoring force due to the elasticity of the sound absorbing material 4, and the periphery of the sound absorbing material is attached to the attachment region surface by the locking claws 32, 32. While being held in the straight direction, the movement of the sound absorbing material in the in-plane direction of the sound absorbing material is restricted by the projecting members 33, 33, and the sound absorbing material 4 is attached and fixed inside the lower case bulging portion 31.

As the resin foam material constituting the sound absorbing material 4, for example, a polyurethane foam material having an open cell structure can be used. Other preferable sound absorbing materials include synthetic resin foams such as polyolefin foams (polyethylene foams, foamed ethylene-vinyl acetate copolymers, etc.) and polyvinyl chloride foams.

The cell structure of the resin foam material may be any of a closed cell structure, an open cell structure, or a combination of both, but a structure containing at least open cells is preferable from the viewpoint of improving sound absorption. Moreover, when there exists a skin layer on the surface of the manufactured resin foam material, it is preferable to remove and use a skin layer. The ratio of open cells is 60 to 100% (for example, 65 to 99.9%) in all bubbles, and preferably about 70 to 99%.

Further, the density of the sound absorbing material can be selected from a range of about 10 to 100 kg / m ³ , and for example, 15 to 70 kg / m ³ , preferably 18 to 48 kg / m ³ , more preferably, in order to improve the sound deadening property. Is about 20 to 46 kg / m ³ . The air permeability of the sound absorbing material (method based on JIS K6400-7 A method) can be selected from the range of about 0.05 to ⁵ dm ³ / sec. For example, 0.07 to ² dm ³ for improving the sound deadening property. / Sec, preferably 0.1 to 1.4 dm ³ / sec, more preferably about 0.2 to 1.3 dm ³ / sec (particularly 0.3 to 1.2 dm ³ / sec).

The degree of elasticity of the sound absorbing material is as follows. The degree of elasticity is indicated by a value obtained by a hardness measurement test according to JIS K6400. Specifically, a test piece having a size of 380 mm × 380 mm and a thickness of 50 mm is used, and the thickness at the time of 5N load is 75. After compression, the compression is performed again to 25% of the original thickness, and the load (N) after 20 seconds is measured. The degree of elasticity preferable as the sound-absorbing material used in the present invention is the above-mentioned hardness, which is 30 to 500N, preferably 50 to 350N, and more preferably 70 to 260N. If the hardness is too small, the holding force of the sound absorbing material tends to be insufficient, and if the hardness is too large, it becomes difficult to house the sound absorbing material 4 in the bulging portion 31 of the lower case and fix it with the claw member.

The thickness and size of the sound absorbing material may be determined based on the relationship between the sound deadening performance and the layout space, but the preferred thickness t of the sound absorbing material in the representative embodiment is about 3 mm to 100 mm, more preferably about 5 mm to 30 mm. The length and width are preferably about 30 to 500 mm, more preferably about 50 to 300 mm.

The effect which the said embodiment of this invention has is demonstrated.
According to the embodiment, the locking claw 32 that holds the sound absorbing material 4 in the direction perpendicular to the surface of the attachment region S, and the protruding member 33 that restricts the movement of the sound absorbing material 4 in the in-plane direction of the attachment region S. By using in combination, the sound absorbing material 4 can be easily fixed to the mounting region. That is, without using an adhesive or an adhesive, the sound absorbing material can be attached using the elasticity of the sound absorbing material, and the operation is simple. And it is possible to reduce the number of places where the use of adhesives and adhesives and the caulking process of pin members, which was the cause of complicated installation work, is effective in simplifying the process of attaching the sound absorbing material. is there.

Further, in the positional relationship in the circumferential direction of the sound absorbing material, when the position where the protruding member 33 is provided is between the locking claws 32, 32 adjacent to each other, the sound absorbing material is placed below the locking claws 32. Since the projecting member 33 can be operated without interfering with the operation of pushing into the sound absorbing member, it is particularly effective from the viewpoint of simplifying the sound absorbing material attaching operation.

Further, as in the above-described embodiment, the projecting member 33 is a tapered pin-shaped member extending in the direction perpendicular to the mounting region S (that is, the direction through the sound absorbing material) and has a length that penetrates the sound absorbing material. If the projecting member 33 is configured so that the sound absorbing material 4 is not substantially held / restrained in the direction perpendicular to the mounting area surface, the sound absorbing material may be caught by the projecting member 33 during the mounting operation. This is particularly effective for simplifying the operation of mounting the sound absorbing material.

From the viewpoint of simplifying the mounting operation of the sound absorbing material, it is preferable that the projecting member 33 and the locking claw 32 are provided apart from each other, and the distance W is defined as d < When W <10 * d, it is particularly effective in simplifying the sound absorbing material mounting operation while enhancing the mounting reliability. When the sound absorbing material is relatively hard (elastic modulus is large), even if the separation distance W is increased with respect to the thickness d, the sound absorbing material is easily retained.

And according to this invention, the latching nail | claw 32 which hold | maintains the sound-absorbing material 4 in the surface normal direction of the attachment area | region S, and the projection member 33 which regulates the movement of the sound-absorbing material 4 to the in-plane direction of the attachment area | region S are provided. By using in combination and fixing at least a part of the sound absorbing material peripheral portion, it is possible to improve the reliability of the sound absorbing material attachment at the site.
That is, in the sound-absorbing material mounting structure of the present invention, even if the sound-absorbing material is likely to float up as shown in FIG. The protrusion member 33 provided in the vicinity of the front end prevents the peripheral edge of the sound absorbing material 4 from being pulled out from the stop claw 32 and prevents the stop claw 32 from being insufficiently locked. . Therefore, it becomes difficult to be influenced by the air flow inside the duct, and the mounting state of the sound absorbing material by the locking claws can be reliably maintained.

In order to secure the effect of locking the sound absorbing material by the locking claw 32, a protrusion, a row of protrusions, a ridge, a sawtooth protrusion, and a return shape are formed on the portion where the locking claw 32 contacts the surface of the sound absorbing material. It is preferable to additionally provide a shape that prevents the sound absorbing material 4 and the locking claw 4 from shifting, and an example of such a locking claw shape is shown in FIG. In FIG. 6, only the engaging claw portion is shown in an enlarged manner, and the lower case member shows only a cut portion.

In the example of the latching claw shown in FIG. 6, a protruding line 32 b is provided on the lower side of the locking claw body part 32 a, that is, on the surface directly facing the sound absorbing material. The cross section is provided in a return shape that prevents the sound absorbing material from moving in the direction of separation. According to the locking claw of this example, the sound absorbing material 4 is more effectively prevented from being detached from the locking claw, and the sound absorbing material is attached more reliably.

The present invention is not limited to the first embodiment, and can be implemented with various modifications. Although other embodiments of the present invention will be described below, in the following description, portions different from the above embodiment will be mainly described, and the same portions will be denoted by the same reference numerals and detailed description thereof will be omitted. . These embodiments and modifications can be implemented by combining some of them or replacing some of them.

FIG. 7 shows an example in which a sound absorbing material is attached to the inside of an air cleaner provided in an intake path for supplying air to an automobile engine as a second embodiment of the present invention. FIG. 7 shows a sectional view of the air cleaner in an exploded state. The air cleaner is composed of a box-like lower case 5, an upper case 6 and a filter element 7 sandwiched between them, and the air flows upstream of the air cleaner. A duct member (not shown) that flows into the lower case 5 through the suction port 50, is filtered by the filter element 7, and is provided downstream of the air cleaner from the discharge port 61 provided in the upper case 6. A ventilation path is constructed and used to be supplied to the engine through (not shown).

In this embodiment, the sound absorbing material 4 is attached to an attachment region provided inside the lower surface of the lower case 5. The sound absorbing material 4 is fixed at its peripheral edge by claw members 52 and 52 and projecting members 53 and 53. In the present embodiment, the claw member 52 is configured by a short wall-like portion that rises vertically from the bottom surface of the lower case, and a claw portion that is provided so as to be bent from the upper edge of the wall-like portion to the upper surface of the sound absorbing material. . Other points are the same as in the first embodiment.

Also in the present embodiment, as in the first embodiment, it is possible to ensure the attachment of the sound absorbing material while simplifying the operation of attaching the sound absorbing material.

As described above, the member to which the sound absorbing material is attached in the present invention is not particularly limited as long as it is a member constituting a part of a series of ventilation paths. It may be a duct member as in the first embodiment, or may be a case member of an air cleaner as in the second embodiment, or a member that forms part of another case member, for example, an air-cooled battery housing case. May be.

The shape of the mounting area of the sound absorbing material is not particularly limited, but from the viewpoint of easily using a flat plate-shaped sound absorbing material with excellent availability, the mounting area is a flat plate, a curved surface with a small degree of bending, or a bent surface. It is preferable. In addition, the shape of the sound absorbing material and its mounting region is not limited to the rectangle as in the above embodiment, and the present invention can be applied to various shapes of the sound absorbing material such as a circle, an ellipse, a triangle, and other polygonal shapes. It is.

The specific shape of the locking claw is that the sound absorbing material peripheral edge is sandwiched between the sound absorbing material mounting surface (31a) and the locking claw (32) and can be held in the direction perpendicular to the sound absorbing material mounting area. Various shapes can be used. For example, as in the locking claw 32 of the first embodiment, it may be configured to extend the portion constituting the peripheral duct surface, or like the locking claw 52 of the second embodiment, A short wall may be raised from the bottom surface of the case once perpendicularly to the bottom surface, and a claw portion for locking the sound absorbing material so as to be bent from the upper edge of the wall may be provided.

The specific shape of the protruding member is not limited to the tapered pin shape shown in the above embodiment, and various shapes of protruding members such as a rod shape, a plate shape, and a hollow column shape can be employed. An example in which a plate-like protruding member is erected on the lower case member 3 is shown in FIG. If the surface of the protruding member is smooth, the sound absorbing material attaching operation is facilitated. On the contrary, if the protrusion of the protruding member is provided with a return protrusion, the certainty of fixing the sound absorbing material can be further increased. And the hole 41 provided in the sound-absorbing material 4 corresponding to the protruding member may be a through hole or a hole that does not penetrate. The shape of the hole does not need to exactly match the shape of the protruding member, and there may be a gap between the hole and the protruding member. Note that it is preferable that the hole and the projecting member be assembled without gaps in order to securely hold the sound absorbing material. Further, the hole provided in the sound absorbing material may be a circular hollow hole 41 as illustrated in FIG. 2 with respect to the first embodiment, but as in the example of the sound absorbing material illustrated in FIG. It may be a slit-shaped hole 41 ′ in which a slit is cut. Even if the cross-section of the hole is smaller than the cross-section of the protruding member, such as a slit-shaped hole, if the foamed resinous sound-absorbing material is extended around the hole, installation is easy and sound-absorbing It is preferable for securely holding the material.

FIG. 8 shows a variation in the relative arrangement of the locking claws and the protruding members as seen from the direction perpendicular to the mounting region. The present invention can also be implemented in this way. In these drawings, the sound-absorbing material, the locking claw, and the projecting member are mainly shown, and details of the case member are omitted. In the example of FIG. 8A, the protruding members 33, 33 are engaged with the locking claws 32, 32 in the direction along the peripheral edge of the sound absorbing material with respect to the locking claws 32, 32 arranged at the peripheral edge of the sound absorbing material 4. They are provided at positions corresponding to each other (that is, at positions that match each other) at positions inside the sound absorbing material periphery from the locking claws 32. With such a configuration, it is possible to directly suppress the sound absorbing material from coming out of the locking claw by the projecting member, so that the sound absorbing material can be particularly securely attached.

Further, in the example shown in FIG. 8B, the projecting members 33 and 33 are adjacent to each other in the direction along the periphery of the sound absorbing material with respect to the locking claws 32 and 32 arranged on the periphery of the sound absorbing material 4. It is arranged in the middle of the locking claws 32, 32 (preferably at a substantially central position) and close to the periphery of the sound absorbing material to the extent that the locking claws protrude toward the inside of the sound absorbing material. Yes. Providing the protruding member at such a position can also effectively prevent the sound absorbing material from coming out of the locking claw, and in particular, the sound absorbing material can be securely attached.

Further, the sound absorbing material mounting structure of the present invention can be used together with a conventionally known sound absorbing material mounting member (such as a caulking pin member). In FIG. 13, the figure which looked at the sound-absorbing material and the lower case from the direction perpendicular to the sound-absorbing material mounting surface is shown for still another embodiment. In the present embodiment, the periphery of the sound absorbing material 4 is fixed by the locking claws 32 and the projection members 33 similar to those of the first embodiment, and further, the sound absorbing material 4 is locked so as to penetrate the substantially central portion of the sound absorbing material 4. A protrusion 34 is provided. The locking projection 34 is provided such that a portion raised from the bottom surface of the case member 3 in a plate shape penetrates the sound absorbing material, and a claw portion formed so as to bend the tip of the plate-shaped portion is integrated. Is provided. In the locking projection 34, the plate-like portion holds the sound absorbing material in the mounting area plane direction, and the claw portion holds the sound absorbing material in the mounting area plane direction. While the locking protrusion 34 is added to the central portion of the sound absorbing material as in the present embodiment, the sound absorbing material has a sound absorbing material mounting structure in which the peripheral edge of the sound absorbing material is combined with the locking claw 32 and the protruding member 33 as in the first embodiment. When fixing the sound-absorbing material, the protruding member 33 is located inside the triangle, particularly preferably near the center of gravity of the triangle, with respect to the locking protrusion 34 and the locking claws 32, 32 arranged close to each other in a triangular arrangement. Thus, it is preferable to arrange the projecting member 33. In such a case, it is particularly easy to perform the operation of attaching the sound absorbing material.

The flat sound absorbing material 4 made of a resin foam material may be a flat plate shape as a whole shape of the sound absorbing material, and is not limited to one having a smooth surface, and is formed by so-called profile processing. In this case, a plurality of ridges and valleys may be formed so as to be distributed on the surface of the sound absorbing material, or a plurality of ridges and grooves may be alternately arranged in a wave shape. . It is preferable that the sound-absorbing material subjected to such profile processing is particularly attached so that the surface side on which the unevenness exists directly faces the attachment region S of the case member. By mounting in such a manner, a so-called back air layer can be formed between the sound absorbing material 4 and the case member, so that the sound absorbing performance is improved.

The sound absorbing material mounting structure can be widely applied to other technical fields other than those described in the embodiment. For example, the present invention is not limited to the case where a sound absorbing material is attached to the inner surface of a member constituting a part of a duct system through which air flows, and the sound absorbing material is applied to an object formed in a panel shape. It can also be applied when mounting. Examples of such panel-like members include automobile engine covers, instrument panels, and various soundproof cover members, and the sound absorbing material attaching method of the present invention can be applied when attaching sound absorbing materials to these members. is there.

According to the present invention, it is possible to reliably attach a sound absorbing material to a case member constituting a series of ventilation paths by a simple mounting operation, and to provide noise reduction to the ventilation path. High utility value.

DESCRIPTION OF SYMBOLS 1 Sound absorption duct 2 Upper case member 3 Lower case member 31 The bulging part 32 Locking claw 33 Projection member S Sound absorption material attachment area 31a, Mounting surface 4 Sound absorption material 5 Lower case member 52 Locking claw 53 Projection member 6 Upper case member 7 Filter element

Claims (3)

In the attachment area provided on the inner peripheral surface of the member constituting a part of the ventilation path,
A sound absorbing material mounting structure in which a rectangular and flat sound absorbing material made of a resin foam material is mounted,
A locking claw that is provided at the periphery of the sound absorbing material and that locks the sound absorbing material without passing through the sound absorbing material and holds the sound absorbing material in a direction perpendicular to the mounting area surface;
With a protruding member that is provided in the direction penetrating the sound absorbing material in the vicinity of the locking claw and restricts the movement of the sound absorbing material in the in-plane direction of the mounting area,
At least one side of the peripheral portion of the sound absorbing material is fixed , and
In the side, a plurality of locking claws are provided so as to be separated from each other in the extending direction of the side,
In the positional relationship in the extending direction of the sides, the sound absorbing material mounting structure in which the position where the protruding member is provided is the middle of the adjacent locking claws . The projecting member is a member that extends in a direction perpendicular to the surface of the mounting region and that penetrates the sound absorbing material, and the projecting member does not substantially hold the sound absorbing material in the direction perpendicular to the mounting region surface. Sound absorbing material mounting structure. The sound absorbing material mounting structure according to claim 1 or 2, wherein the protruding member is provided apart from the locking claw, and a distance between the protruding members is set to 1 to 10 times a thickness of the sound absorbing material.

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