Acoustic board

Abstract

The invention discloses an acoustic board, and relates to the technical field of noise reduction, the acoustic board comprises a plurality of first kerf groups arranged at intervals along a first direction X. Each first kerf group comprises a plurality of first kerfs arranged at intervals along a second direction Y. The first kerf penetrates through the two surfaces of the acoustic board in the thickness direction Z, and the first direction X, the second direction Y and the thickness direction Z are perpendicular to one another. When the acoustic board is stretched along the first direction X, the gap of the first kerf is widened and deformed, so that the acoustic board can be stretched along the first direction X more easily, and the size of the acoustic board in the first direction X is finely adjusted. Therefore, when the size of the wall surface is slightly different from the size of the acoustic board, the acoustic board can be matched with the size of the wall surface by stretching the acoustic board, so that the construction is more convenient, and the acoustic board can be conveniently paved on the wall surface and is more attractive.

Description

Technical Field

[0001] The invention relates to the technical field of noise reduction, and in particular to a sound absorbing board. Background Art

[0002] Sound-absorbing panels are a type of panel made of porous materials that can absorb sound and provide decoration. For example, they can be laid on the wall to absorb the energy of indoor sound waves and reduce noise. At the same time, the sound-absorbing panels themselves can beautify the wall and create a more beautiful indoor environment.

[0003] The applicant has found that the actual installation of the sound-absorbing board faces a problem. The wall sizes of each household are different, but the size of the sound-absorbing board is of uniform specifications. Therefore, during the installation on the wall, the remaining area of ​​the wall is often smaller than that of a single board. For example, the width / height of the wall is smaller than the width / height of the sound-absorbing board. In this case, it is necessary to measure the size on site, cut the PET board, and then install it on the wall.

[0004] There is an obvious problem with this approach: manual cutting has large errors, and after installation, it may not cover the entire wall well, leaving large gaps, affecting the sound absorption effect and aesthetics.

[0005] In addition, during the actual installation process, the remaining area of ​​the wall may be slightly larger than a single board. In this case, it is difficult to cut the sound-absorbing board to fill it, but not filling it will also leave a large gap, affecting the sound absorption effect and aesthetics.

[0006] The above contents are only used to help understand the technical solution of the present application and do not constitute an admission that the above contents are prior art. Summary of the invention

[0007] The object of the present invention is to provide a sound absorbing panel, the size of which can be conveniently adjusted.

[0008] To achieve the above-mentioned object of the invention, the present invention provides a sound absorbing plate, comprising a plurality of first slit groups arranged at intervals along a first direction X, each of the first slit groups comprising a plurality of first slits arranged at intervals along a second direction Y, the first slits passing through two surfaces of the sound absorbing plate in a thickness direction Z, and the first direction X, the second direction Y and the thickness direction Z are perpendicular to each other.

[0009] Furthermore, at least part of the first slits at the outermost sides of the first slit groups are connected to the outer side surface of the sound absorbing plate.

[0010] Furthermore, one or all of the two outermost first slits of one of two adjacent first slit groups are connected to the outer side surface of the sound absorbing plate;

[0011] One or all of the two outermost first slits of all the first slit groups are connected to the outer side surface of the sound absorbing plate.

[0012] Furthermore, the plurality of first slits in the first slit group are located on the same straight line.

[0013] Furthermore, two adjacent first slits along the first direction X are staggered in the second direction Y.

[0014] Furthermore, the distance between two adjacent first slits of the first slit group along the second direction Y is 5 mm to 100 mm;

[0015] The length of the first slit is 10 to 60 mm;

[0016] The interval between two adjacent first slit groups along the first direction X is 3 to 300 mm.

[0017] Further, a plurality of the first slit groups are distributed throughout the entire sound absorbing board along the first direction X; or,

[0018] The sound absorbing plate is provided with at least one first slit area, and the first slit group is arranged in the first slit area.

[0019] Furthermore, the surface of the sound absorbing board is covered with fluff to conceal the cut seams.

[0020] Furthermore, the sound absorbing plate includes a plurality of second slit groups arranged at intervals along the second direction Y, each of the second slit groups includes a plurality of second slits arranged at intervals along the first direction X, and the second slits penetrate both surfaces of the sound absorbing plate in the thickness direction Z.

[0021] Furthermore, at least part of the first slits at the outermost sides of the second slit groups are communicated with the outer side surface of the sound absorbing plate.

[0022] Further, one or all of the two outermost second slits of one of two adjacent second slit groups are connected to the outer side surface of the sound absorbing plate; or,

[0023] One or all of the two outermost second slits of all the second slit groups are connected to the outer side surface of the sound absorbing plate.

[0024] Furthermore, the plurality of second slits in the second slit group are located on the same straight line.

[0025] Further, two adjacent second slits along the second direction Y are staggered in the first direction X.

[0026] Furthermore, the distance between two adjacent second slits of the second slit group along the first direction X is 5 mm to 100 mm;

[0027] The length of the second slit is 10 to 60 mm;

[0028] The spacing distance between two adjacent second slit groups along the second direction Y is 3 to 300 mm.

[0029] Further, a plurality of the second slit groups are distributed throughout the entire sound absorbing board along the second direction Y; or,

[0030] The sound absorbing plate is provided with at least one second slit area, and the second slit group is arranged in the second slit area.

[0031] Compared with the prior art, the present invention has the following beneficial effects: in the present invention, the sound absorbing board includes a plurality of first slit groups arranged at intervals along the first direction X, each of the first slit groups includes a plurality of first slits arranged at intervals along the second direction Y, and the first slits penetrate the first slit groups on both surfaces of the sound absorbing board in the thickness direction Z. When the sound absorbing board is stretched along the first direction X, the gaps of the first slits will become wider and deformed, so that the sound absorbing board can be more easily stretched along the first direction X and its size in the first direction X can be fine-tuned. In this way, when the size of the wall is slightly different from that of the sound absorbing board, the size of the sound absorbing board and the wall can be matched by stretching the sound absorbing board, so that the construction is more convenient, and the wall can be easily covered, which is more beautiful. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 Schematic diagram of the structure of the sound absorbing board of some embodiments of the present invention, in which the sound absorbing board has slits.

[0033] Figure 2 yes Figure 1 A plan view of the acoustic panel is shown.

[0034] Figure 3 yes Figure 2 Enlarged view of part II.

[0035] Figure 4 It is a partial schematic diagram of the sound absorbing panel of some embodiments of the present invention.

[0036] Figure 5 1 is a plan view of a sound absorbing panel of some embodiments of the present invention, in which the sound absorbing panel includes cross-arranged slits.

[0037] Figure 6 yes Figure 5 Enlarged view of part III.

[0038] Figure 7 1 is a plan view of a sound absorbing panel of some embodiments of the present invention, in which the sound absorbing panel is provided with a first slit area and a second slit area.

[0039] Figure 8 1 is a plan view of a sound absorbing panel according to some embodiments of the present invention. DETAILED DESCRIPTION

[0040] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. It is to be understood that the specific embodiments described herein are only used to explain the present application, rather than to limit the present application. It should also be noted that, for ease of description, only some structures related to the present application are shown in the accompanying drawings, rather than all structures. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0041] The terms "including" and "having" and any variations thereof in this application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products or devices.

[0042] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0043] like Figure 1 As shown, the present invention proposes a sound absorbing board, which is roughly in the shape of a plate and has two surfaces located at both ends of its thickness direction Z and an outer side surface 1c connected between the two surfaces. The sound absorbing board includes a plurality of first slit groups 30 arranged at intervals along a first direction X, and each first slit group 30 includes a plurality of first slits 31 arranged at intervals along a second direction Y, and the first slits 31 penetrate the two surfaces of the sound absorbing board in the thickness direction Z. The first direction X, the second direction Y and the thickness direction Z are perpendicular to each other (the angles between them are all 90°).

[0044] The first slit group 30 is arranged so that when the sound absorbing board is stretched along the first direction X, the slits of the first slits 31 will become wider and deformed, so that the sound absorbing board can be more easily stretched along the first direction X and its size in the first direction X can be fine-tuned. In this way, when the size of the wall is slightly different from that of the sound absorbing board, the size of the sound absorbing board and the wall can be matched by stretching the sound absorbing board, which makes construction more convenient, and can be conveniently covered on the wall, making it more beautiful.

[0045] Figure 1 and Figure 2 The sound absorbing board shown is rectangular. Usually, the shape of the wall is rectangular, so the rectangular sound absorbing board can better fit the wall. It is understandable that the laying area of ​​the sound absorbing board does not have to be a wall, but can also be other laying areas. The sound absorbing board can also be designed into other shapes as needed. For example, when the sound absorbing board is roughly circular, it is suitable for laying in a circular area, and when the sound absorbing board is trapezoidal, it is suitable for laying in a trapezoidal area. In other embodiments, the sound absorbing board can also be other shapes.

[0046] In some embodiments, at least part of the first slit groups 30 located at the outermost first slits 31 are connected to the outer side surface 1c of the sound absorbing board, so that the outer edge of the sound absorbing board does not play a framing role, and it is easier to stretch the sound absorbing board along the first direction X to deform the sound absorbing board. Further, optionally, among two adjacent first slit groups 30, at least one of the first slit groups 30 located at the outermost first slits 31 is connected to the outer side surface 1c of the sound absorbing board, for example, Figures 1 to 3 In the illustrated embodiment, the outermost first slit 31 of one of the two adjacent first slit groups 30 is connected to the outer side surface 1c of the sound absorbing board, while the other is not connected, so that the sound absorbing board can maintain a certain structural strength while being easily stretched and deformed. Figure 4 In the illustrated embodiment, the outermost first slits 31 of all first slit groups 30 are connected to the outer side surface 1c of the sound absorbing board, so that the sound absorbing board is more easily stretched and deformed. It is understandable that there are two outermost first slits 31 of the first slit group 30, one of which may be connected to the outer side surface 1c of the sound absorbing board and the other may not be connected, or both of the outermost two first slits 31 may be connected to the outer side surface 1c of the sound absorbing board, so that the sound absorbing board can be deformed more evenly.

[0047] Optionally, the plurality of first slits 31 of the first slit group 30 are located on the same straight line, so that the sound absorbing plate 30 can be better deformed along the first direction X and is less likely to be distorted in shape.

[0048] refer to Figures 1 to 3Two first slits 31 adjacent to each other in the first direction X are staggered in the second direction Y, so that the sound absorbing plate can reliably deform along the first direction X and has good structural strength.

[0049] It is understandable that parameters such as the number and spacing of the first slit groups 30 and the number, spacing and length of the first slits 31 have a great influence on the difficulty and elongation of the sound absorbing panel.

[0050] In some embodiments, reference Figure 3 , the distance D1 between two adjacent first slits 31 of the first slit group 30 along the second direction Y is 5 to 100 mm, so that the distance D1 between two adjacent first slits 31 is not too large to cause too small deformation of the sound absorbing board, nor is it too close to cause insufficient strength of the sound absorbing board and easy to tear. It can be understood that the distance between each two adjacent first slits 31 can be the same (that is, the first slits 31 of the first slit group 30 are arranged at equal distances) or different (that is, the first slits 31 of the first slit group 30 are arranged at unequal distances).

[0051] For ease of description, the slits connected to the outer side surface 1c of the sound absorbing plate are referred to as outer slits, and the slits not connected to the outer side surface 1c of the sound absorbing plate are referred to as inner slits. Figure 3 The length L2 of the inner slits of the first slit group 30 is 10 to 60 mm, so that the first slits 31 have a suitable length, and the sound absorbing board has a good deformation amount after stretching while ensuring the structural strength of the sound absorbing board. It can be understood that the lengths of all the inner slits can be the same, or the lengths of at least two inner slits can be different.

[0052] In some embodiments, reference Figure 3 , the spacing D2 between two adjacent first slit groups 30 along the first direction X is 3 to 300 mm, so that the spacing between two adjacent first slit groups 30 is more appropriate. On the one hand, the distance between two adjacent first slits 31 is not too small, which is conducive to ensuring the overall structural strength of the sound absorbing board, and can also prevent the adjacent slits from contacting due to misoperation during processing, and avoid the sound absorbing board from being cut off. On the other hand, the spacing between two adjacent first slits 31 is not too large, resulting in a small deformation amount or uneven deformation of the sound absorbing board. It can be understood that the distance between each two adjacent first slit groups 30 can be the same (that is, the first slit groups 30 are arranged at equal distances) or different (that is, the first slit groups 30 are arranged at unequal distances).

[0053] It can be understood that when the slit groups are arranged along the first direction X, the sound absorbing board is more suitable for stretching and deforming along the first direction X. In order to enable the sound absorbing board to adjust its size in more directions to adapt to walls of different sizes, in some embodiments, reference Figure 5 and Figure 6 The sound absorbing board further includes a plurality of second slit groups 32 arranged at intervals along the second direction Y, each second slit group 32 includes a plurality of second slits 33 arranged at intervals along the first direction X, and the second slits 33 penetrate the two surfaces of the sound absorbing board in the thickness direction Z. In this way, the size of the sound absorbing board can be adjusted along the first direction X and the second direction Y, and can adapt to more situations where the size needs to be adjusted.

[0054] The structure and parameters of the second slit group 32 may refer to the above description of the first slit group 30 , and an example is as follows.

[0055] In some embodiments, at least part of the second slit groups 32 located at the outermost second slits 33 are connected to the outer side surface 1c of the sound absorbing board, so that the outer edge of the sound absorbing board does not play a framing role, and it is easier to stretch the sound absorbing board along the second direction Y to deform the sound absorbing board. Further, optionally, among two adjacent second slit groups 32, at least one of the second slit groups 32 located at the outermost second slits 33 is connected to the outer side surface 1c of the sound absorbing board, for example, Figure 5 and Figure 6 In the illustrated embodiment, the outermost second slit 33 of one of the two adjacent second slit groups 32 is connected to the outer side surface 1c of the sound absorbing board, while the other is not connected, so that the sound absorbing board can maintain a certain structural strength while being easily stretched and deformed. For another example, it can be arranged that the outermost second slits 33 of all the second slit groups 32 are connected to the outer side surface 1c of the sound absorbing board, so that the sound absorbing board is more easily stretched and deformed. It can be understood that there are two outermost second slits 33 of the second slit group 32, one of which can be connected to the outer side surface 1c of the sound absorbing board and the other not, or both of the outermost two second slits 33 can be connected to the outer side surface 1c of the sound absorbing board, so that the sound absorbing board can be deformed more evenly.

[0056] Optionally, the plurality of second slits 33 of the second slit group 32 are located on the same straight line, so that the sound absorbing plate 30 can be better deformed along the second direction Y and is less likely to be distorted in shape.

[0057] refer to Figure 5 and Figure 6 The two second slits 33 adjacent to each other in the second direction Y are staggered in the first direction X, so that the sound absorbing plate can reliably deform along the second direction Y and has good structural strength.

[0058] In some embodiments, the outermost second slit 33 (ie, outer slit) of the second slit group 32 is connected to the outer side surface 1c of the sound absorbing board, so that the outer edge of the sound absorbing board does not act as a frame, making it easier for the sound absorbing board to stretch along the second direction Y.

[0059] It can be understood that, similarly, parameters such as the number and spacing of the second slit groups 32 and the number, spacing and length of the second slits 33 have a great influence on the elongation of the sound absorbing panel.

[0060] In some embodiments, reference Figure 6 , the distance D3 between two adjacent second slits 33 of the second slit group 32 along the first direction X is 5 to 100 mm, so that the distance between two adjacent second slits 33 is not too large to cause too small deformation of the sound absorbing board, nor is it too close to cause insufficient strength of the sound absorbing board and easy to tear. It can be understood that the distance between every two adjacent second slits 33 can be the same (that is, the second slits 33 of the second slit group 32 are arranged at equal distances), or different (that is, the second slits 33 of the second slit group 32 are arranged at unequal distances).

[0061] In some embodiments, reference Figure 6 The length L3 of the second slit 33 is 10 to 60 mm, so that the second slit 33 has a suitable length, and the sound absorbing board has a good deformation amount after stretching while ensuring the structural strength of the sound absorbing board. It can be understood that the lengths of all the second slits 33 can be the same, or the lengths of at least two second slits 33 can be different.

[0062] In some embodiments, reference Figure 6 , the spacing D4 between two adjacent second slit groups 32 along the second direction Y is 3 to 300 mm, so that the spacing between two adjacent second slit groups 32 is more appropriate. On the one hand, the distance between two adjacent second slits 33 is not too small, which is conducive to ensuring the overall structural strength of the sound absorbing board, and can also prevent the adjacent slits from contacting due to misoperation during processing, avoiding the sound absorbing board from being cut off. On the other hand, the spacing between two adjacent second slits 33 is not too large, resulting in a small deformation amount or uneven deformation of the sound absorbing board. It can be understood that the distance between each two adjacent second slit groups 32 can be the same (that is, the second slit groups 32 are arranged at equal distances) or different (that is, the second slit groups 32 are arranged at unequal distances).

[0063] Optionally, the surface of the sound absorbing board is covered with fluff, which may be of the material itself (for example, PET board itself has fluff), or may be added later. When the sound absorbing board is stretched and the deformation of the sound absorbing board in the first direction X and / or the second direction Y does not exceed 2%, since the deformation of each cut is very small, the cut is basically unrecognizable under the coverage of the fluff, which is more beautiful.

[0064] In some embodiments, one of the first direction X and the second direction Y is the length direction of the sound absorbing board, and the other is the width direction of the sound absorbing board, so that the length and width of the sound absorbing board can be adjusted. It can be understood that the first direction X and the second direction Y do not necessarily correspond to the length direction or the width direction of the sound absorbing board, and can also be arranged obliquely.

[0065] By providing the slit groups arranged at intervals in the first direction X and the second direction Y of the sound absorbing plate, the size of the sound absorbing plate in the first direction X and the second direction Y can be adjusted. When the length and / or width of the sound absorbing plate is slightly smaller than the wall, the sound absorbing plate can be stretched to make its length and / or width adapt to the size of the wall, so as to more fully cover the wall and ensure the aesthetics and sound absorption effect.

[0066] In some embodiments, a plurality of first slit groups 30 are distributed throughout the entire sound absorbing board along the first direction X, so that the adjustable size range of the sound absorbing board can be maximized. In other embodiments, the sound absorbing board is provided with at least one first slit area 34, and the first slit group 30 is provided in the first slit area 34, so that the size range of the sound absorbing board that can be stretched can be adjusted by adjusting the size of the first slit area 34 in the first direction X, thereby reducing damage to the sound absorbing board and ensuring aesthetics. Figure 7 The case where one first slit area 34 is provided is shown. When there are two or more first slit areas 34 , the plurality of first slit areas 34 are arranged along the first direction X at intervals.

[0067] Similarly, in some embodiments, a plurality of second slit groups 32 are distributed throughout the entire sound absorbing board along the second direction Y, so that the adjustable size range of the sound absorbing board can be maximized. In other embodiments, the sound absorbing board is provided with at least one second slit area 35, and the second slit group 32 is provided in the second slit area 35, so that the size range of the sound absorbing board that can be stretched can be adjusted by adjusting the size of the second slit area 35 in the second direction Y, thereby reducing damage to the sound absorbing board and ensuring aesthetics. Figure 7 The case where one second slit area 35 is provided is shown. When there are two or more second slit areas 35 , the plurality of second slit areas 35 are arranged along the second direction Y at intervals.

[0068] It is understandable that when stretching the sound absorbing board, the part that needs to be stretched can be stretched as needed, without stretching the entire board. For example, Figure 8 In the case shown, the sound absorbing plate is tilted at one side for some reason, so the sound absorbing plate is trapezoidal. At this time, the upper left corner can be stretched to deform it into a rectangle ( Figure 7 By stretching different parts of the sound-absorbing board, the shape of the sound-absorbing board can be adjusted more flexibly according to the usage scenario, making it more convenient to use.

[0069] It is understandable that in order to allow the sound-absorbing board to be stretched and deformed, the sound-absorbing board is preferably made of a flexible porous material with good sound absorption performance and anti-fracture performance. When a 9 mm thick board is folded at least 100 times without breaking, it can be considered that the board is made of a flexible material. Optionally, the material of the sound-absorbing board is melamine sound-absorbing foam, melamine cotton, polyurethane foam or polyester fiber.

[0070] The above are only specific embodiments of the present invention, and any other improvements made based on the concept of the present invention are considered to be within the protection scope of the present invention.

Claims

1. A sound absorbing panel, characterized in that: The sound absorbing plate comprises a plurality of first slit groups (30) arranged at intervals along a first direction X, each of the first slit groups (30) comprises a plurality of first slits (31) arranged at intervals along a second direction Y, the first slits (31) penetrate two surfaces of the sound absorbing plate in a thickness direction Z, and the first direction X, the second direction Y and the thickness direction Z are perpendicular to each other.

2. The sound absorbing panel according to claim 1, characterized in that: At least part of the first slits (31) at the outermost sides of the first slit group (30) are in communication with the outer side surface (1c) of the sound absorbing plate.

3. The sound absorbing panel according to claim 2, characterized in that: One or all of the two outermost first slits (31) of one of two adjacent first slit groups (30) are in communication with the outer side surface (1c) of the sound absorbing plate; One or all of the two outermost first slits (31) of all the first slit groups (30) are in communication with the outer side surface (1c) of the sound absorbing plate.

4. The sound absorbing panel according to claim 1, characterized in that: The plurality of first slits (31) of the first slit group (30) are located on the same straight line.

5. The sound absorbing panel according to claim 1, characterized in that: Two adjacent first slits (31) along the first direction (X) are staggered in the second direction (Y).

6. The sound absorbing panel according to claim 1, characterized in that: The distance between two adjacent first slits (31) of the first slit group (30) along the second direction Y is 5 mm to 100 mm; The length of the first slit (31) is 10 to 60 mm; The spacing distance between two adjacent first slit groups (30) along the first direction X is 3 to 300 mm.

7. The sound absorbing panel according to claim 1, characterized in that: A plurality of the first slit groups (30) are distributed throughout the entire sound absorbing board along the first direction X; or, The sound absorbing plate is provided with at least one first slit area (34), and the first slit group (30) is arranged in the first slit area (34).

8. The sound absorbing panel according to claim 1, characterized in that: The surface of the sound absorbing board is covered with fluff to cover the cut seams.

9. The sound absorbing panel according to any one of claims 1 to 8, characterized in that: The sound absorbing plate comprises a plurality of second slit groups (32) arranged at intervals along a second direction Y, each of the second slit groups (32) comprises a plurality of second slits (33) arranged at intervals along the first direction X, and the second slits (33) penetrate two surfaces of the sound absorbing plate in a thickness direction Z.

10. The sound absorbing panel according to claim 9, characterized in that: At least part of the first slits (31) at the outermost sides of the second slit group (32) are in communication with the outer side surface (1c) of the sound absorbing plate.

11. The sound absorbing panel according to claim 10, characterized in that: One or all of the two outermost second slits (33) of one of two adjacent second slit groups (32) are in communication with the outer side surface (1c) of the sound absorbing plate; or, One or all of the two outermost second slits (33) of all the second slit groups (32) are in communication with the outer side surface (1c) of the sound absorbing plate.

12. The sound absorbing panel according to claim 9, characterized in that: The plurality of second slits (33) of the second slit group (32) are located on the same straight line.

13. The sound absorbing panel according to claim 9, characterized in that: Two adjacent second slits (33) along the second direction Y are staggered in the first direction X.

14. The sound absorbing panel according to claim 9, characterized in that: The distance between two adjacent second slits (33) of the second slit group (32) along the first direction X is 5 mm to 100 mm; The length of the second slit (33) is 10 to 60 mm; The spacing distance between two adjacent second slit groups (32) along the second direction Y is 3 to 300 mm.

15. The sound absorbing panel according to claim 9, characterized in that: A plurality of the second slit groups (32) are distributed throughout the entire sound absorbing board along the second direction Y; or, The sound absorbing plate is provided with at least one second slit area (35), and the second slit group (32) is arranged in the second slit area (35).

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