Soundproof cover

Abstract

This soundproof cover is attached to a noise source in an openable and closable manner and covers the noise source to reduce noise, and is provided with a first cover part 11 and a second cover part 12 which are connected through a hinge part 15. A claw part 31 having a first protrusion 32 protruding in a direction away from the hinge part 15 is provided in the first cover part 11, and an engagement part 41 having an engagement surface 42 that engages with the first protrusion 32 is provided in the second cover part 12. The first cover part 11 is provided with a restriction part 51 for restricting the engagement part 41 in a state of being engaged with the claw part 31 from being displaced in a direction away from the hinge part 15.

Description

soundproof cover

[0001] The present invention relates to a soundproof cover that reduces noise by covering a noise source.

[0002] In automobiles and other vehicles, soundproof covers have been proposed to cover noise sources such as engines, compressors, and motors in order to reduce noise generated by these noise sources. Electric vehicles (EVs) and hybrid vehicles (HVs) are particularly quieter than conventional internal combustion engine vehicles, and therefore require a corresponding reduction in noise levels from noise sources such as electric compressors for air conditioning systems. This demands soundproof covers with high sound-absorbing and sound-insulating properties. Patent Document 1 discloses a soundproof cover having multiple (e.g., two) cover sections connected by a hinge section formed of an integral hinge and molded to cover the entire outer surface of the noise source, each cover section having at least one fiber layer. For example, each cover section has a shape obtained by dividing a cylinder into two sections along a plane including its central axis, i.e., a semi-cylindrical shape. The cover sections are also called segments, surrounding walls, etc., and are formed, for example, from molded resin. The soundproof cover opens and closes as one cover part rotates relative to the other around the hinge axis; when open, the inner surfaces of each cover part are exposed, and when closed, the two cover parts come into contact with each other in places other than the hinge parts, forming a space that surrounds the noise source.

[0003] Similarly, Patent Documents 2 to 4 disclose soundproof covers having a structure in which a pair of semi-cylindrical cover sections, the inner surfaces of which are provided with a resin foam as a sound-absorbing material, are connected by a hinge section. Some kind of engagement mechanism is required to secure the soundproof cover in a closed state. The engagement mechanism is generally formed integrally with the cover sections, which are molded resin products. In the soundproof cover described in Patent Document 2, a first engagement part having an engagement piece formed with an engagement claw protruding outward is provided on one cover section, and a second engagement part having an elongated hole is provided, and the engagement piece is inserted into the elongated hole to engage with the first engagement part, thereby closing the soundproof cover. In the soundproof cover described in Patent Document 3, a first engagement part having a protrusion is provided on one cover section, and a second engagement part having a through hole is provided on the other cover section, and the soundproof cover is closed by engaging the protrusion with the through hole. In the soundproof cover described in Patent Document 4, an engaging portion having an engaging hole is provided on one cover portion, and an engaging receiving portion that is insertable and detachable into the engaging hole and that hooks onto the engaging portion when passed through the engaging hole is provided on the other cover portion. In particular, in the soundproof cover described in Patent Document 4, the engaging portion is configured to be expandable so that the engaging hole expands in the extension direction of the engaging portion, making it easy to attach the soundproof cover, and when removing the engaging portion from the engaging receiving portion, the engaging hole expands by pulling the tip of the engaging portion, allowing the engaging portion to be easily removed from the engaging receiving portion.

[0004] Although not related to soundproof covers, Patent Document 5 discloses a locking mechanism for engaging a protector body and a cover in a wire harness protector that houses and holds a wire harness. In this locking mechanism, the wire harness protector cover has an insertion piece with an engaging protrusion at its end, and further has elastic pieces cantilevered by notches formed on both ends of the engaging protrusion. The protector body has a frame wall portion with an engaging surface for engaging the insertion piece, and an insertion piece engaging portion that forms an insertion piece insertion hole by a wall member that is part of the side wall portion. In this locking mechanism, the insertion piece engages with the insertion piece insertion hole by pushing the insertion piece into the insertion piece insertion hole, and the engagement can be easily released by pressing the free end of the elastic piece.

[0005] JP 2021-170086 A JP 2020-133408 A JP 2022-145996 A JP 2022-169192 A Japanese Patent No. 3066714 A

[0006] A soundproof cover, which has a structure in which a pair of semi-cylindrical cover parts are connected by a hinge part, is required to be easy to assemble to the noise source, not easy to open when assembled to the noise source, and easy to open when performing maintenance on the noise source. A locking mechanism that engages a claw part with an engaging part is used to close the soundproof cover, but in soundproof covers used in vehicles, etc., there is a risk that the claws will come off the engaging part due to creep caused by high temperatures or vibration, causing the soundproof cover to open unintentionally. If the claws are made more rigid to make it harder for them to come off the engaging part, it becomes difficult to open the soundproof cover for maintenance, etc.

[0007] An object of the present invention is to provide a soundproof cover whose claws do not easily come off from their engaging portions when exposed to high temperatures or vibrations, and which can be easily opened for maintenance, etc.

[0008] According to one aspect of the present invention, there is provided a soundproof cover having a resin cover and a sound-absorbing material provided on an inner surface of the resin cover, the resin cover having a first cover portion, a second cover portion, and a hinge portion connecting the first cover portion and the second cover portion, the soundproof cover being openable and closable by rotation of the first cover portion and the second cover portion around the hinge portion as a pivot axis. In this soundproof cover, one or more claw portions having a first protrusion protruding in a direction away from the hinge portion are formed on an edge portion of the first cover portion away from the hinge portion, and engaging portions having an engaging surface on a free end side that engages with the first protrusion are formed on an edge portion of the second cover portion away from the hinge portion at positions corresponding to the claw portions, the engaging portions engaging with the first protrusion when the soundproof cover is closed. Furthermore, a restricting portion corresponding to at least one of the claw portions is provided on the first cover portion to restrict displacement of the engaging portion away from the hinge portion when engaged with the claw portion.

[0009] According to the present invention, a soundproof cover is obtained in which the claws do not easily come off the engaging portions when exposed to high temperatures or vibrations, and which can be easily opened for maintenance, etc.

[0010] FIGS. 1A and 1B are a perspective view and a front view, respectively, of a soundproof cover according to a first embodiment of the present invention, and FIG. 1C is a perspective view of the soundproof cover in a half-open state. FIG. 2A is a perspective view of a resin cover, and FIG. 2B is a perspective view of a sound-absorbing material. FIG. 3A is an enlarged perspective view of a locking mechanism, and FIG. 3B is a schematic cross-sectional view illustrating the engagement process of the locking mechanism. FIGS. 4A, 4B, and 4C are an enlarged perspective view, an enlarged front view, and an enlarged plan view, respectively, of a locking mechanism having a restricting portion. FIG. 4D is an enlarged perspective view showing a portion belonging to the first cover portion in the locking mechanism having a restricting portion. FIG. 4E is an enlarged perspective view showing a portion belonging to the second cover portion in the locking mechanism having a restricting portion. FIG. 5A is a schematic cross-sectional view taken along line 5A-5A in FIG. 4B. FIG. 5B is a schematic cross-sectional view taken along line 5B-5B in FIG. 4B. FIG. 5C is a schematic cross-sectional view illustrating the disengagement operation of a locking mechanism having a restricting portion. FIG. 6A is an enlarged perspective view showing a locking mechanism in a soundproof cover according to the second embodiment, and FIG. 6B is a schematic cross-sectional view showing the disengagement operation of the locking mechanism in the second embodiment.

[0011] Next, embodiments of the present invention will be described with reference to the drawings. Figures 1A to 1C are diagrams illustrating a soundproof cover according to a first embodiment of the present invention. In particular, Figures 1A and 1B are a perspective view and a front view, respectively, of the soundproof cover in a closed state, and Figure 1C is a perspective view of the soundproof cover in a partially open state. This soundproof cover is used, for example, in an automobile to cover a noise-source component to block noise. Here, the noise-source component is an electric compressor for an air conditioner, and the soundproof cover is attached to this compressor. However, the object to which the soundproof cover according to the present invention is attached is not limited to a compressor.

[0012] The soundproof cover has a substantially cylindrical shape when closed and includes a resin cover 10 and sound-absorbing materials 21 and 22 attached to the inner surface of the resin cover 10. FIG. 2A is a perspective view of the resin cover 10 when the soundproof cover is fully open, and FIG. 2B is a perspective view of the sound-absorbing materials 21 and 22. The resin cover 10 is divided into a first cover portion 11 and a second cover portion 12, each of which is substantially semi-cylindrical. The first cover portion 11 and the second cover portion 12 are connected via a hinge portion 15, and the soundproof cover opens and closes when the first cover portion 11 and the second cover portion 12 rotate around the hinge portion 15. When the soundproof cover is open, a substantially rectangular opening is formed by the first cover portion 11 and the second cover portion 12, and the hinge portion 15 is formed along substantially the entire length of one long side of the substantially rectangular opening, with the hinge portion 15 serving as the rotation axis. In the first cover portion 11 and the second cover portion 12, the edges of the openings that appear when the soundproof cover is opened are the edges of the first cover portion 11 and the second cover portion 12, respectively. In other words, each of the first cover portion 11 and the second cover portion 12 has a substantially rectangular edge, i.e., an outer periphery, and a hinge portion 15 is provided on one of the long sides of the edge. In practice, the first cover portion 11, the second cover portion 12, and the hinge portion 15 are integrally formed by injection molding of a flexible resin. When the soundproof cover is closed, the edge of the first cover portion 11 and the edge of the second cover portion 12 come into contact with each other, forming a space surrounded by the first cover portion 11 and the second cover portion 12.

[0013] The sound-absorbing material consists of two pieces, with sound-absorbing material 21 provided on the inner surface of first cover portion 11 and sound-absorbing material 22 provided on the inner surface of second cover portion 12. Sound-absorbing materials 21, 22 have a recessed shape that corresponds to the outer shape of the compressor to which the soundproof cover is attached. Sound-absorbing materials 21, 22 are not provided in locations required for attaching the compressor to the vehicle body or in locations where wiring and piping connected to the compressor must pass through; small openings are provided in first cover portion 11 and second cover portion 12 in such locations. By attaching the soundproof cover to the compressor and closing it, sound-absorbing materials 21, 22 come into contact with and surround the compressor, and further, resin cover 10, i.e., first cover portion 11 and second cover portion 12, encases the compressor together with sound-absorbing materials 21, 22. As a result, the sound generated by the compressor is blocked or absorbed by the sound absorbing materials 21 and 22, and is further blocked by the resin cover 10.

[0014] In the soundproof cover of this embodiment, the resin cover 10 maintains its shape as a soundproof cover, improving the ease of assembly of the soundproof cover to components such as compressors, while also providing sound insulation. When the soundproof cover is used, for example, in the engine compartment of an automobile, the resin cover 10 is also required to be heat-resistant. Therefore, for example, a resin that is flexible, heat-resistant, and injection-moldable is used for the resin cover 10. Examples of resin materials that can be used to form the resin cover 10 include polypropylene (PP), polyethylene (PE), acrylonitrile-butadiene-styrene copolymer resin (ABS), ethylene propylene diene rubber (EPDM), polyamide (PA), polyacetal (also known as polyoxymethylene) (POM), and melamine resin (sponge). These resin materials may contain additives (fillers) such as talc. Meanwhile, the sound-absorbing materials 21 and 22 have sound-absorbing and sound-insulating properties as well as vibration-damping capabilities. Furthermore, it is preferable that the sound-absorbing materials 21, 22 do not generate abnormal noise when rubbing against noise-producing components such as a compressor that are in contact with them. From this perspective, the sound-absorbing materials 21, 22 are made of, for example, an open-cell, i.e., breathable, soft urethane resin foam. In addition to soft urethane resin foam, ethylene propylene diene rubber foam or the like can also be used for the sound-absorbing materials 21, 22.

[0015] To enhance the soundproofing and absorbing effects, the sound-absorbing materials 21, 22 are preferably configured to interfere with each other when the soundproof cover is closed, i.e., to press against each other at their outer peripheries. Furthermore, a protruding piece 13 is formed on the edge of the second cover part 12, which overlaps with the inner surface of the first cover part 11 when the soundproof cover is closed, enhancing soundproofing. An extension part 14 is formed on the protruding piece 13 to prevent the protruding piece 13 from extending over the outer surface of the first cover part 11 when the soundproof cover is closed, and this extension part 14 initially abuts against the first cover part 11 to guide the protruding piece 13 when the soundproof cover is closed.

[0016] In the soundproof cover of this embodiment, multiple locking mechanisms for maintaining the closed state are provided at positions away from the hinge portion 15. Each locking mechanism is composed of at least a claw portion 31 provided on the first cover portion 11 and an engagement portion 41 provided on the second cover portion 12 so as to engage with the claw portion 31. In the illustrated example, four locking mechanisms, designated A to D, are provided on the soundproof cover. Since locking mechanisms A to D are provided so as to straddle the first cover portion 11 and the second cover portion 12, the positions of locking mechanisms A to D on the soundproof cover will be explained by explaining the positions of locking mechanisms A to D on the first cover portion 11. The edge of the first cover portion 11 is generally rectangular, and locking mechanisms A to C are provided in this order along the long side of the generally rectangular edge that is not provided with the hinge portion 15—in other words, on the edge opposite the hinge portion 15. The locking mechanism D is provided on the short side of the substantially rectangular edge of the first cover part 11 .

[0017] FIG. 3A is an enlarged perspective view illustrating the locking mechanism, and FIG. 3B is a schematic cross-sectional view illustrating the engagement process of the locking mechanism. As described below, of the four locking mechanisms A to D, locking mechanism A further includes a restriction portion 51 (see FIGS. 4A to 4E and 5A to 5C). Therefore, FIGS. 3A and 3B illustrate locking mechanisms B to D. Each locking mechanism is composed of a claw portion 31 provided at the edge of the first cover portion 11 so as to be slightly raised above the outer surface of the first cover portion 11, and an engagement portion 41 provided on the second cover portion 12 so as to engage with the claw portion 31. The claw portion 31 is formed integrally with the first cover portion 11 from resin, and the engagement portion 41 is formed integrally with the second cover portion 12 from resin. The claw portion 31 is provided with a first protrusion 32 that protrudes in a direction away from the hinge portion 15. The engaging portion 41 is formed to extend from the edge of the second cover portion 12 toward the first cover portion 11 when the soundproof cover is closed, and is provided at its free end with an engaging surface 42 that engages with the first protrusion 32. In the illustrated example, the engaging portion 41 is formed in a "U" shape with two legs 43, 44 that connect to the second cover portion 12, and a beam-like portion that connects the legs 43, 44 is formed at the free end of the engaging portion 41, and this beam-like portion serves as the engaging surface 42. In order to increase the mechanical strength of the engaging portion 41, the legs 43, 44 and the beam-like portion that connects them all have an "L" shaped cross section.

[0018] When the soundproof cover is closed, the first cover part 11 and the second cover part 12 rotate relatively around the rotation axis of the hinge part 15, and the engaging part 41 approaches the claw part 31 as shown by the arrow in Fig. 3B and abuts against the claw part 31 so as to climb over the first protrusion 32. Thereafter, when the soundproof cover is completely closed, the first protrusion 32 of the claw part 31 fits into the inner part of the U-shaped part of the engaging part 41 and engages with the engaging surface 42 of the engaging part 41. Because the first protrusion 32 is engaged with the engaging surface 42, the first cover part 11 and the second cover part 12 are prevented from rotating relatively around the rotation axis in the direction in which the soundproof cover opens.

[0019] However, both the claw portion 31 and the engaging portion 41 are molded from resin, and due to the flexibility of resin, creep may occur when the soundproof cover is subjected to vibration or exposed to high temperatures, causing the first protrusion 32 of the claw portion 31 to disengage from the engaging surface 42 of the engaging portion 41, resulting in the soundproof cover opening unintentionally. To prevent the soundproof cover from opening unintentionally, the soundproof cover of this embodiment includes a restricting portion 51 on the first cover portion 11 of the locking mechanism A that restricts the engaging portion 41, when engaged with the claw portion 31, from displacing away from the hinge portion 15. The restricting portion 51 is also formed integrally with the first cover portion 11 from a resin having the same flexibility as the first cover portion 11. The locking mechanism A equipped with the restricting portion 51 will be described below with reference to FIGS. 4A to 4E and 5A to 5C. FIGS. 4A to 4C are an enlarged perspective view, an enlarged front view, and an enlarged plan view, respectively, of the locking mechanism A. Fig. 4D is an enlarged perspective view showing a portion of locking mechanism A that belongs to first cover portion 11, and Fig. 4E is an enlarged perspective view showing a portion of locking mechanism A that belongs to second cover portion 12. Fig. 4D illustrates claw portion 31 and restricting portion 51 of locking mechanism A, and Fig. 4E illustrates engaging portion 41 of locking mechanism A. Fig. 5A is a schematic cross-sectional view taken along line 5A-5A in Fig. 4B, Fig. 5B is a schematic cross-sectional view taken along line 5B-5B in Fig. 4B, and Fig. 5C is a schematic cross-sectional view showing the disengagement operation of locking mechanism A.

[0020] Like the locking mechanisms B to D, the locking mechanism A also has a claw portion 31 provided on the first cover portion 11 and an engaging portion 41 provided on the second cover portion 12. The claw portion 31 of the locking mechanism A has the same configuration as the claw portion 31 in the locking mechanisms B to D. The engaging portion 41 of the locking mechanism A has the same configuration as the engaging portion 41 in the locking mechanisms B to D, but differs from the engaging portion 41 in the locking mechanisms B to D in that a second protrusion 45 that protrudes in a direction away from the hinge portion 15 is formed on the free end side of the leg portions 43, 44. The restricting portion 51 is formed in an arc shape with both ends connected to the first cover portion 11 so that a hole 52 through which the engaging portion 41 can be inserted is formed between the restricting portion 51 and the surface of the first cover portion 11. When the soundproof cover is closed, as shown in FIGS. 4A and 5B , the second protrusion 45 of the engaging portion 41 passes through the hole 52 and engages with the restricting portion 51. In this state, the engaging portion 41 abuts against the restricting portion 51, so that even if the engaging portion 41 attempts to move away from the hinge portion 15, the engaging portion 41 cannot move. As a result, the engagement between the claw portion 31 and the engaging portion 41 is not released, preventing the soundproof cover from opening unintentionally. On the other hand, when intentionally opening the soundproof cover, as shown in FIG. 5C , the operator places the index finger 61 of their hand 60 over the restricting portion 51 and bends the restricting portion 51 toward them, i.e., outward, as shown in [1]. Then, the operator uses their thumb 62 to push the engaging portion 41 upward, i.e., in the direction to open the soundproof cover, as shown in [2]. By performing this operation, the second protrusion 45 comes off the restricting portion 51, whereby the engagement between the restricting portion 51 and the engaging portion 41 can be easily released, and the soundproof cover can be opened.

[0021] In this embodiment, an inclined portion 53 is formed on the inner peripheral wall of the hole 52 of the restricting portion 51 so that the hole 52 of the restricting portion 51 tapers toward the direction in which the engaging portion 41 moves when the soundproof cover is closed. By providing such an inclined portion 53, the engaging portion 41 that enters the hole 52 when closing the soundproof cover first abuts against the inclined portion 53. This configuration prevents the engaging portion 41 from climbing over the hole 52 and moving toward the outside of the restricting portion 51, and the engaging portion 41 is properly guided to engage with the restricting portion 51. Furthermore, the inclined portion 53 makes it easier to bend the restricting portion 51 with the index finger 61, making it easier to open the soundproof cover. Furthermore, as shown by the arrow in FIG. 4C , the width of the hole 52 is larger than the width of the engaging portion 41 so that the engaging portion 41 can move in the width direction while engaged with the restricting portion 51. The width direction here refers to the direction in which the edge of the first cover part 11 extends at the position of the locking mechanism A, which is the left-right direction in the example shown in Fig. 4C. By allowing the engagement part 41 to move in the width direction within the hole 52, it becomes easier to engage the engagement part 41 with the restriction part 51 and to release the engagement and open the soundproof cover.

[0022] The soundproof cover of this embodiment is provided with four locking mechanisms A to D, and the claws 31 and engagement portions 41 of each locking mechanism A to D engage with each other to maintain the soundproof cover in a closed state. When closing the soundproof cover, as described with reference to FIGS. 3A and 3B , the beam-shaped portions of the engagement portions 41 must overcome the first protrusions 32 of the claws 31. This requires applying a load to the soundproof cover. If the engagement portions 41 of all four locking mechanisms A to D were to simultaneously overcome the claws 31, the load to be applied to the soundproof cover would increase, worsening the ease of attaching the soundproof cover to the noise source. Therefore, in this embodiment, as shown in FIG. 1B , the soundproof cover is placed on a horizontal plane, and the positions at which the first protrusions 32 and engagement surfaces 42 engage are vertically offset for each locking mechanism. That is, the positions at which the first protrusions 32 and engagement surfaces 42 engage are distributed along three straight lines L1 to L3. With this configuration, in a soundproof cover provided with multiple locking mechanisms, when the first cover part 11 and the second cover part 12 are rotated relatively around the rotation axis to close the soundproof cover, the engaging parts 41 of each locking mechanism overcome the claw parts 31 at different rotation angles, dispersing the load. Also, when opening the soundproof cover, after the claw parts 31 have been disengaged from the engaging parts 41 in one locking mechanism, when the claw parts 31 are disengaged from the engaging parts 41 in the other locking mechanisms, the initially disengaged claw parts 31 can be prevented from re-engaging with the engaging parts 41.

[0023] Next, the location of the locking mechanism A including the restricting portion 51 will be described. It is preferable to provide multiple locking mechanisms in the soundproof cover, regardless of whether the restricting portion 51 is provided, to ensure that the closed state can be maintained. In particular, it is preferable to provide multiple locking mechanisms on the edge of the first cover portion 11 opposite the hinge portion 15. On the other hand, considering the operation of intentionally opening the soundproof cover, it is preferable to provide only one locking mechanism including the restricting portion 51. From the perspective of preventing the soundproof cover from opening unintentionally, it is preferable to provide the locking mechanism including the restricting portion 51 on the edge of the first cover portion 11 opposite the hinge portion 15. When multiple locking mechanisms are provided on the edge of the first cover portion 11 opposite the hinge portion 15, it is preferable to provide the restricting portion 51 on the locking mechanism closest to the center of the first cover portion 11. Alternatively, the restricting portion 51 may be provided on the locking mechanism closest to the center of the multiple locking mechanisms provided on the edge of the first cover portion 11 opposite the hinge portion 15. By arranging the locking mechanism having the regulating portion 51 in this manner, damage or detachment of the engaging portion 41 is prevented, and the ease of opening and closing the soundproof cover is improved. Furthermore, the locking mechanism having the regulating portion 51 can function as a positional reference and guide when assembling the soundproof cover to the noise source.

[0024] Next, a soundproof cover according to a second embodiment will be described. The soundproof cover according to the second embodiment is similar to the soundproof cover according to the first embodiment described with reference to FIGS. 1A through 5C, except for the configuration of the restricting portion 51. FIGS. 6A and 6B show the locking mechanism A of the soundproof cover according to the second embodiment, with FIG. 6A being an enlarged perspective view and FIG. 6B being a schematic cross-sectional view showing the disengagement operation. In the soundproof cover according to the second embodiment, a lever-shaped handle 55 is provided on the upper surface of the restricting portion 51 of the locking mechanism A so as to bend away from the edge of the first cover portion 11. With this locking mechanism A, the operation for closing the soundproof cover is the same as that of the first embodiment, but the operation for opening the soundproof cover is different. To open the soundproof cover, first, push the handle 55 toward the second cover portion 12, as indicated by the arrow [1] in FIG. 6B. As a result, the restricting portion 51 bends outward (toward the user) so as to rotate using the principle of a lever, with the connection point between the restricting portion 51 and the first cover portion 11 as the fulcrum. As a result, the engagement between the engaging portion 41 and the restricting portion 51 is released. Thereafter, as in the first embodiment, the soundproof cover can be opened by pushing the engaging portion 41 in the direction indicated by the arrow [2]. The second embodiment has the advantage that the force required to bend the restricting portion 51 to open the soundproof cover is smaller.

[0025] REFERENCE SIGNS LIST 10 Resin cover 11 First cover portion 12 Second cover portion 13 Convex piece 14 Extension portion 15 Hinge portion 21, 22 Sound absorber 31 Claw portion 32 First protrusion 41 Engagement portion 42 Engagement surface 45 Second protrusion 51 Restriction portion 52 Hole portion 53 Inclined surface 55 Handle A to D Locking mechanism

Claims

1. A soundproof cover having a resin cover and sound-absorbing material provided on the inner surface of the resin cover, the resin cover having a first cover part, a second cover part, and a hinge part connecting the first cover part and the second cover part, and capable of being opened and closed by the first cover part and the second cover part rotating around the hinge part which is a rotation axis, one or more claw parts having a first protrusion protruding in a direction away from the hinge part are formed at one or more positions away from the hinge part on the edge part of the first cover part, an engagement part having an engagement surface on a free end side which engages with the first protrusion is formed at each position away from the hinge part on the edge part of the second cover part corresponding to the claw parts, the claw part and the engagement part engage with each other when the soundproof cover is closed, and a restricting part is provided on the first cover part corresponding to at least one of the claw parts, which restricts the displacement of the engagement part when engaged with the claw part in the direction away from the hinge part.

2. A soundproof cover as described in claim 1, wherein a second protrusion protruding in a direction away from the hinge portion is formed on the free end side of the engagement portion, the restricting portion is flexible and formed in an arc shape with both ends connected to the first cover portion so that a hole portion through which the engagement portion is inserted is formed between the restricting portion and the surface of the first cover portion, and an inclined portion is formed on the inner wall of the hole portion in the restricting portion.

3. The soundproof cover according to claim 2, wherein the second projection of the engagement portion inserted through the hole engages with the restriction portion.

4. A soundproof cover as described in claim 3, wherein the direction in which the edge of the first cover part extends at the position where the regulating part is provided is defined as the width direction, and the width of the hole is larger than the width of the engaging part so that the engaging part can move in the width direction in the hole when the second protrusion is engaged with the regulating part.

5. A soundproof cover as described in any one of claims 1 to 4, wherein a plurality of claw portions are provided on the first cover portion, and the regulating portion is provided corresponding to the claw portion that is closest to the center position of the first cover portion in the extension direction of the pivot axis among the claw portions provided on the edge side of the first cover portion opposite the hinge portion.

6. A soundproof cover as described in any one of claims 1 to 4, wherein a plurality of claw portions are provided on the first cover portion so that at least one of the claw portions engages with the corresponding engagement portion at a rotation angle different from the other claw portions when the first cover portion and the second cover portion rotate around the rotation axis to close the soundproof cover.

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