JP7744646B2 - Soundproofing fittings and suspended ceiling structure - Google Patents

Description

The present invention relates to sound-insulating fittings that are attached to the ends of diagonal members in a suspended ceiling structure that has a ceiling substrate suspended from a structural body such as a building, and to the suspended ceiling structure to which they are attached.

For example, as disclosed in Patent Documents 1-3, earthquake-resistant reinforcement fittings are known that reinforce suspended ceiling structures, which have rafter supports and rafters suspended from building structures such as floor slabs or beams, at the intersections between the rafter supports and rafters. Here, in addition to conventional steel-based ceilings formed by rafter supports and rafters, various types of ceiling substructures known as system ceilings are known as suspended ceiling structures.

Incidentally, the suspended ceiling structures disclosed in Patent Documents 1-3 feature earthquake-resistant braces placed within the ceiling. Specifically, the lower ends of four diagonally placed braces are connected to a single earthquake-resistant reinforcing bracket attached to the intersection between the rafter support and the rafter.

As disclosed in Patent Document 4, vibration-damping members are sometimes installed to prevent vibrations caused by vehicle traffic, walking, etc. from being transmitted to the ceiling panels via the suspension bolts and braces and generating noise in the structure supporting the suspended ceiling. This document discloses a configuration in which vibration-damping hangers are attached midway along the suspension bolts, and vibration-damping members are attached midway along the braces.

Patent No. 4963484 Patent No. 4845212 Patent No. 6290167 Japanese Patent Application Laid-Open No. 2009-2435

However, while the seismic performance of earthquake-resistant reinforced ceilings has been confirmed, the reality is that the soundproofing performance, which is added as an additional function, has not yet been sufficiently confirmed through testing.

The present invention aims to provide a highly versatile sound-insulating metal fitting that can be applied to a variety of suspended ceiling structures and has high sound insulation properties, as well as a suspended ceiling structure to which it is attached.

To achieve the above-mentioned objective, the sound-insulating metal fittings of the present invention are attached to the ends of diagonal members of a suspended ceiling structure having a ceiling substrate suspended from a structure, and comprise a first member fixed to the ceiling substrate or the structure, a second member fixed to the end of the diagonal member, and a sound-insulating functional part interposed between the first member and the second member, characterized in that one of the first member and the second member is formed in a columnar shape and the other is formed in a cylindrical shape surrounding the first member.

Here, the first member and the second member can be configured such that one has a shaft portion formed in a columnar shape at the center of a flat plate portion, and the other has a sheath tube portion formed in a cylindrical shape surrounding the shaft portion, with vibration-damping material serving as the sound-insulating functional part interposed between the outer surface of the shaft portion and the inner surface of the sheath tube portion, and acoustic insulation is provided between the flat plate portion and the end face of the sheath tube portion. It is also preferable that the sheath tube portion be provided with attachment pieces for connecting the ends of multiple diagonal members.

The invention also relates to a suspended ceiling structure having a ceiling substrate suspended from a structure, and is characterized in that it comprises any of the sound-insulating metal fittings described above and a diagonal member having one end fixed to the sound-insulating metal fitting, the diagonal member connecting the structure and the ceiling substrate via the sound-insulating metal fitting. Here, the ceiling substrate may be suspended by a suspension bolt equipped with an anti-vibration hanger.

The sound-insulating metal fittings of the present invention, configured in this manner, are attached to the ends of diagonal members in a suspended ceiling structure with a ceiling substructure, such as a conventional steel-substrate ceiling. That is, the first member of the sound-insulating metal fitting is attached to the ceiling substructure, and the other, the second member, is attached to the end of the diagonal member. A sound-insulating functional part is then provided between the first and second members.

In this way, if it is interposed between the end of the diagonal member and the ceiling substrate, it can be installed regardless of the shape of the diagonal member, making it highly versatile and applicable to a variety of suspended ceiling structures to improve sound insulation.

Furthermore, such sound-insulating metal fittings can be easily manufactured by covering the shaft portion formed in the center of the flat plate with a sheath tube portion and placing vibration-damping material between the shaft portion and the sheath tube portion.

Furthermore, if the sheath tube section is provided with multiple mounting pieces, sound-insulating metal fittings can be placed where multiple diagonal members, such as braces, are concentrated, allowing a single fitting to provide sound-insulating functionality to multiple diagonal members.

In a suspended ceiling structure suspended from a structural body, soundproofing functionality can be easily ensured by attaching soundproofing fittings to the ends of the diagonal members connecting the structural body to the ceiling substrate. In particular, when the ceiling substrate is suspended by hanging bolts equipped with vibration-proof hangers, the diagonal members do not bear the weight of the ceiling panels, etc., allowing the soundproofing performance of the vibration-proof hangers to be fully utilized.

FIG. 2 is a side view illustrating the configuration of the suspended ceiling structure of the present embodiment. FIG. 2 is a perspective view illustrating the configuration of a suspended ceiling structure. FIG. 2 is an exploded perspective view illustrating the configuration of the sound-insulating metal fitting according to the present embodiment. FIG. 2 is an explanatory diagram showing the configuration of the outer member of the sound-insulating metal fitting. FIG. 1 is a perspective view illustrating the configuration of a sound-insulating metal fitting according to an embodiment of the present invention. FIG. 2 is an exploded perspective view illustrating the configuration of the reinforcing metal fitting. FIG. 2 is a perspective view illustrating the configuration of a reinforcing metal fitting. FIG. 10 is a perspective view illustrating a state in which a reinforcing metal fitting is attached to an intersection portion. FIG. 10 is a plan view illustrating the state in which the sound-insulating metal fitting is attached to the reinforcing metal fitting. 10 is a cross-sectional view taken along the arrow AA in FIG. 9. 10 is a cross-sectional view taken along the arrow BB in FIG. 9. 1 is an explanatory diagram showing a schematic diagram of the state of the suspended ceiling structure of the present embodiment. FIG. FIG. 1 is an explanatory diagram showing, in model form, four evaluation test specimens used in an experiment conducted to confirm the sound insulation properties of the suspended ceiling structure of this embodiment. FIG. 10 is an explanatory diagram comparing the experimental results of two evaluation specimens. FIG. 10 is an explanatory diagram comparing the experimental results of two other evaluation test specimens. 1 is an explanatory diagram showing a schematic configuration of a suspended ceiling structure according to a first embodiment of the present invention;

Embodiments of the present invention will now be described with reference to the drawings. Figures 1 and 2 are diagrams illustrating the configuration of a suspended ceiling structure 1 according to this embodiment. Figures 3 to 5 are diagrams illustrating the configuration of a sound-insulating metal fitting 2 according to this embodiment.

The suspended ceiling structure 1 is installed in a variety of buildings, such as gymnasiums, assembly halls, public facilities that serve as bases for disaster emergency response, and buildings. The suspended ceiling structure 1 of this embodiment can be applied to both existing suspended ceilings and newly constructed suspended ceilings.

As shown in Figure 1, multiple suspension bolts 13 are suspended at intervals from the underside of the floor slab 11 and beams that form the building's structural body, and the siding support parts 14 that form the ceiling substructure are suspended from hangers 131 at the lower ends of the suspension bolts 13, which serve as suspension members.

As shown in Figure 2, the siding members 15 that make up the ceiling underlayment are attached at intervals in the axial direction of the siding support members 14, facing in a direction that is approximately perpendicular to the siding support members 14. While this embodiment will be described using a ceiling underlayment formed by the siding support members 14 and the siding members 15 as an example, application is not limited to this. For example, the sound-insulating fittings 2 of this embodiment can also be applied to a system ceiling equipped with a ceiling underlayment made of T-bars arranged in a lattice pattern.

A ceiling panel 16, such as gypsum board, is attached to the underside of the rough edge 15. As shown in Figure 1, if the end 16a of the ceiling panel 16 is spaced a specified distance or more from the wall 12 of the building, the end 16a can be prevented from being pressed against the wall 12 and being damaged by shaking during an earthquake.

In this embodiment, we will explain how to reinforce a suspended ceiling suspended by suspension bolts 13 equipped with vibration-isolating hangers 7 by placing diagonal members such as braces in a manner that does not impair sound insulation. In other words, even if sound insulation is ensured by hanging the ceiling with suspension bolts 13 equipped with vibration-isolating hangers 7, if the braces placed afterwards do not have sound insulation properties, those braces will act as sound bridges, impairing the sound insulation provided by the vibration-isolating hangers 7.

As shown in Figure 2, the suspended ceiling structure 1 of this embodiment comprises a pair of braces 8, 8 as diagonal members in the soffit support direction, arranged in a roughly V-shape in side view along the axial direction of the soffit support portion 14, which is the first component of the ceiling substructure, and a pair of braces 8, 8 as diagonal members in the soffit direction, arranged in a roughly V-shape in side view along the axial direction of the soffit portion 15, which is the second component of the ceiling substructure.

The upper end of the brace 8 is fixed to the top of the hanging bolt 13 via a mounting bracket 81. Meanwhile, a reinforcing bracket 3 (described below) is attached to the intersection 17A between the siding support portion 14 and the siding portion 15. The lower end of the brace 8 is then attached to the sound-insulating bracket 2 attached to the reinforcing bracket 3.

As shown in Figure 3, the sound-insulating metal fittings 2 are primarily composed of an inner member 21, which serves as the first or second member, an outer member 22, which serves as the second or first member, and a vibration-damping material 23, which serves as a sound-insulating functional part and is interposed between the inner member 21 and the outer member 22.

The inner member 21 has a shaft portion 212 formed in a columnar shape in the center of the flat plate portion 211. Figure 4 shows a plan view and two side views of the inner member 21. The inner member 21 has a flat plate portion 211 that is rectangular in plan view, such as a square, and a shaft portion 212 that protrudes upward from the center of the flat plate portion 211.

Bolt holes 215 are drilled at each corner of the flat plate portion 211. These bolt holes 215 are holes for securing the inner member 21 to the reinforcing bracket 3, which will be described later. The shaft portion 212 of the inner member 21 can be formed, for example, from a rectangular steel pipe. In addition, the rigidity of the shaft portion 212 can be increased by closing the upper end opening of the square steel pipe with the upper cover portion 213.

As shown in Figure 3, a rectangular cylindrical vibration-damping material 23 is attached around the shaft portion 212 of this internal member 21. The vibration-damping material 23 is made of vibration-damping rubber or the like. This vibration-damping material 23 does not have to be formed in a rectangular cylindrical shape; for example, it may be formed in a rectangular sheet shape that is attached to each of the four side surfaces of the shaft portion 212.

The outer member 22 is formed in a cylindrical shape and surrounds the shaft portion 212 of the inner member 21 and the vibration-damping material 23. It is mainly composed of a rectangular cylindrical sheath tube portion 221 and multiple mounting pieces 222 for attaching the lower end of the brace 8.

The mounting pieces 222 extend from each corner of the sheath tube portion 221, with the extension directions of the four mounting pieces 222 intersecting at right angles at the center of the sheath tube portion 221. The mounting pieces 222 also have mounting holes 222a drilled into them for inserting fixing bolts or the like.

Figure 5 shows a perspective view of the sound-insulating fitting 2 with the vibration-damping material 23 and outer member 22 attached to the inner member 21. When the suspended ceiling structure 1 is in its normal state, a gap is formed between the lower end surface of the sheath tube portion 221 of the outer member 22 and the upper surface of the flat plate portion 211 of the inner member 21, providing acoustic insulation.

The size of the sheath tube portion 221 is set according to the thickness of the vibration-damping material 23 to be interposed between it and the shaft portion 212. By interposing the vibration-damping material 23 between the outer surface of the shaft portion 212 and the inner surface of the sheath tube portion 221, it is possible to suppress the transmission of micro-vibrations between the brace 8 and the reinforcing metal fitting 3. In short, as long as acoustic insulation is achieved between the brace 8 and the reinforcing metal fitting 3, a simple gap may be provided between the shaft portion 212 and the sheath tube portion 221.

The following provides an example of the details of the reinforcing bracket 3 used to attach the sound-insulating bracket 2 to the intersection 17A between the soffit support portion 14 and the soffit portion 15. The sound-insulating bracket 2 is not limited to being attached to the soffit support portion 14 via the reinforcing bracket 3; by modifying the reinforcing bracket appropriately depending on the components of the ceiling substrate, it can be adapted to any suspended ceiling. Furthermore, regardless of the type of suspended ceiling, the joint strength of the intersection 17A can be increased by inserting the reinforcing bracket 3.

As shown in Figures 6-8, the reinforcing bracket 3 is attached to the intersection 17A between the sill support portion 14 and the sill portion 15. The lower end of the brace 8 is then connected to this reinforcing bracket 3 via the sound-insulating bracket 2.

As shown in Figure 6, the sill support portion 14 onto which the hanger 131 of the suspension bolt 13 is hooked is formed in a roughly U-shaped cross section, for example, by an upper flange 141 forming the upper end surface of a roughly horizontal plane, a lower flange 142 that is roughly parallel to it, and a roughly vertical web 143 connecting the side edges of the upper flange 141 and lower flange 142.

On the other hand, the siding part 15, which is fixed to the siding support part 14, is formed by a bottom part 153, side walls 152, 152 rising from both sides of the bottom part, and lip parts 151, 151 bent twice inward from the upper edge of each of the side walls 152, 152. In other words, the siding part 15 can be made of steel material with a roughly U-shaped cross section and lip parts 151, 151. Furthermore, the lip part 151 is formed by its upper surface and hanging surface into a roughly L-shaped cross section facing horizontally.

As shown in Figures 6-8, the reinforcing bracket 3 is mainly composed of a first bracket 4 that is fixed to the sill support portion 14 located above, and a second bracket 5 that straddles the first bracket 4 and is fixed to the sill portion 15.

The first metal fitting 4 is mainly composed of a bent portion 41 located in the center and spanning the siding support portion 14, a notch 42 formed at the bottom so that the siding portion 15 can fit into it, and screws 43 as a joining means for fixing the first metal fitting 4 to the siding support portion 14.

As shown in Figure 6, the bent portion 41 is formed in a roughly gate-shaped cross section so as to cover the soffit support portion 14 from above. In other words, the bent portion 41 is formed in a shape that covers both sides of the upper flange 141 and web 143 of the soffit support portion 14.

The lower part of the bent part 41 has a notch 42 cut out in a shape that allows the upper part of the edge part 15 to fit into it. In other words, the notch 42 surrounds the top and both sides of the edge part 15.

The bent portion 41 formed in this way is placed on the upper flange 141 of the sill support portion 14, and the cutout portion 42 is fitted into the sill portion 15 below it, thereby placing the first metal fitting 4 on the upper end of the side wall portions 152, 152.

In addition, on both sides of the bent portion 41, screws 43, 43 are continuously inserted through the web 143 of the soffit support portion 14 and the first metal fitting 4 to join them. As a result, the first metal fitting 4 is fixed to the soffit support portion 14.

In this way, by using screws 43 that penetrate both the first metal fitting 4 and the soffit support portion 14 as the joining means, a strong joint can be achieved due to the shear resistance of the screws 43. In other words, if the screws 43 that penetrate the first metal fitting 4 are screwed directly into the web 143 of the soffit support portion 14, a strong joint can be achieved that prevents misalignment between the soffit support portion 14 and the first metal fitting 4. In this state, even if the soffit support portion 14 and the soffit portion 15 are not joined, movement of the first metal fitting 4 in any direction other than the axial direction of the soffit portion 15 will be restricted.

Furthermore, ribs 44, 44 extend from both axial edges of the sill support portion 14 of the first fitting 4 in a direction approximately parallel to the axial direction of the sill portion 15. These ribs 44, 44 increase the rigidity of the first fitting 4, which is manufactured by bending a sheet material such as a steel plate.

The second metal fitting 5 is placed over the first metal fitting 4 attached to the siding support 14 in this way. The second metal fitting 5 has a pair of plate portions (51, 52) that face each other across one lip portion 151 of the siding 15.

The pair of plate portions (51, 52) are each formed from a steel plate or the like with central grooves 511, 521 so that they can straddle the soffit support portion 14. Here, the plate portion located on the lip portion 151 side (inside the soffit portion 15) is referred to as the lip side plate portion 51, and the plate portion located on the outside of the soffit portion 15 is referred to as the stop plate portion 52.

The pair of plate portions (51, 52) are provided with stage portions 53A, 53B, which extend in opposite directions from their respective upper edges and form flat surfaces while contacting the upper flange 141, which forms the upper end surface of the sill support portion 14. Here, the flat surface provided on the lip portion side plate portion 51 is referred to as stage portion 53A, and the flat surface provided on the stop plate portion 52 is referred to as stage portion 53B.

The stage portion 53A has a recess 532A that connects to the groove 511 provided in the center of the lip side plate portion 51 to allow the siding support portion 14 to straddle it. Meanwhile, the stage portion 53B has a recess 532B that connects to the groove 521 provided in the center of the stop plate portion 52 to allow the siding support portion 14 to straddle it.

The recesses 532A, 532B provided on each of the pair of stage portions 53A, 53B form a continuous rectangular space as shown in Figure 7. The space formed by these recesses 532A, 532B accommodates the upper surface of the bent portion 41 of the first fitting 4. In short, the stage portions 53A, 53B and the upper surface of the bent portion 41 form a large, approximately flush rectangular plane on the sill support portion 14.

The wide rectangular plane formed by the pair of stage sections 53A, 53B and extending from the upper flange 141 has mounting holes 531 drilled in the vertical direction, for example near the corners. In this embodiment, an example is described in which four mounting holes 531 are provided in each corner.

In addition, a hook portion 512, which is generally L-shaped when viewed from the side, is provided on the lower part of the lip side plate portion 51, as shown in Figures 6 and 7. This hook portion 512 is positioned so that it can be hooked onto the lip portion 151 from below.

The hook portion 512 is formed by cutting a rectangular section of the lower part of the lip side plate portion 51 into the top and both sides and tilting it toward the lip portion 151 (see Figure 10).

As shown in Figures 6-8, an insertion hole 513 is drilled above the hook portion 512, and a bolt portion 54 passes through it, sandwiching the lip portion 151. This bolt portion 54 passes from the lip portion side plate portion 51 toward the insertion hole 523 of the retaining plate portion 52, and a nut is attached to the tip that protrudes toward the retaining plate portion 52.

In contrast, a washer 55 made of a rectangular (approximately square) steel plate or similar is positioned on the head side of the bolt 54, as shown in Figure 8. In other words, the fastening force introduced between the lip side plate 51 and the retaining plate 52 by tightening the bolt 54 is transmitted through the contact surface between the washer 55 and the lip side plate 51.

To limit the rotation of the washer portion 55, ribs 514 as shown in Figure 10 can be made to protrude from the side edges of the lip side plate portion 51. In this case, ribs 514, 514 protrude from both axial edges of the siding portion 15 of the lip side plate portion 51 in a direction approximately parallel to the axial direction of the siding support portion 14. These ribs 514, 514 can increase the rigidity of the lip side plate portion 51, which is manufactured by bending a plate material such as a steel plate.

Furthermore, as shown in Figure 8, rib portions 522, 522 can be extended from both axial edges of the sill portion 15 of the retaining plate portion 52 in a direction approximately parallel to the axial direction of the sill support portion 14 to increase rigidity.

When a fastening force is applied between the plate portions (51, 52) by the bolt portion 54, the lip portion 151 is crushed, and the second fitting 5 is fixed to the edge portion 15. In other words, when the fastening force of the bolt portion 54 is transmitted to the lip portion side plate portion 51 via the washer portion 55, the lip portion 151 in contact with it is deformed and crushed.

The second fitting 5 is crimped by the applied fastening force and the deformed lip 151, restricting axial movement of the siding 15. The lip side plate 51 and stop plate 52, which are formed in a gate shape and straddle the first fitting 4 and siding support 14, also restrict axial movement of the siding 15 of the second fitting 5.

Furthermore, although not shown, it is preferable that the first metal fitting 4, which is fixed to the sill support portion 14, and the second metal fitting 5, which is fixed to the sill portion 15 across the first metal fitting 4, be joined by an integration means.

For example, a joining piece can be protruded from the lip side plate portion 51 at a substantially right angle and positioned along the outer surface of the bent portion 41 of the first fitting 4, and screws can be screwed in to join the first fitting 4 and the second fitting 5 together. In particular, by using multiple screws to join the first fitting 4 and the second fitting 5 together, the joining strength is increased compared to when they are joined together with a single screw, further enhancing the unity of the two.

In this way, the intersection 17A between the siding support 14 and the siding 15 can be fixed with the highly rigid reinforcing metal fitting 3. Simply attaching this reinforcing metal fitting 3 increases the joint strength of the intersection 17A, reinforcing it.

In addition, the stage portions 53A and 53B of the reinforcing bracket 3, to which the force from the brace 8 is transmitted, are in contact with the upper flange 141 of the siding support portion 14, so even if a load acts from above, it can be supported by the reaction force of the siding support portion 14.

On the other hand, as shown in Figure 2, reinforcing clips 6 and clips 61 are attached to intersections other than intersection 17A where reinforcing bracket 3 is attached. Reinforcing clip 6 can connect soffit support portion 14 and soffit portion 15 more firmly than a regular clip 61 attached to the intersection between soffit support portion 14 and soffit portion 15 where reinforcing bracket 3 is not attached.

The sound-insulating bracket 2 is attached to the stage portions 53A and 53B of the reinforcing bracket 3 attached to the intersection 17A in the manner described above. Figures 9-11 are plan and cross-sectional views illustrating the state in which the sound-insulating bracket 2 is attached to the reinforcing bracket 3.

Bolt holes 215 are drilled in the corners of the flat plate portion 211 of the inner member 21 that constitutes the lower part of the sound-insulating bracket 2 at positions that overlap with the mounting holes 531 of the stage portions 53A and 53B (see Figure 5). The inner member 21 can be fixed to the reinforcing bracket 3 by passing bolts 24 through these bolt holes 215 and mounting holes 531 (see Figure 8) and fastening them with nuts 241. Note that if the mounting holes 531 of the stage portions 53A and 53B have female threads, the inner member 21 can be fixed by bolts 24 screwed in from above without using nuts.

The mounting pieces 222 of the outer member 22, which are attached so as to surround the shaft portion 212 of the inner member 21, extend from each corner of the sheath tube portion 221 of the outer member 22 in the axial direction of the siding support portion 14 and the siding portion 15.

As shown in Figures 10 and 11, arm members 82 are attached diagonally to the mounting pieces 222 extending in the axial direction using bolts 821. The lower ends of the braces 8 are joined to these arm members 82.

The arm material 82 is formed in a roughly L-shaped cross section for attaching the lower ends of the braces 8. In this way, the lower ends of the four braces 8 arranged in two directions in a roughly V-shape when viewed from the side can be attached together to a single sound-insulating bracket 2.

The sound-proofing fittings 2 prevent vibrations and sounds generated on the structural side, such as on the floor slab 11, from being transmitted via the braces 8 to the space below the ceiling boards 16. Conversely, sound generated in the space below the ceiling boards 16 can also be prevented from being transmitted via the braces 8 to upper floors, etc.

Furthermore, by providing sound-insulating brackets 2 on the reinforcing brackets 3 attached to the intersection 17A between the siding support 14 and the siding 15, the installation locations are consolidated, reducing the number of parts used and improving workability. In other words, compared to the case where vibration-damping members are interposed on each of the four braces 8, it is only necessary to install the sound-insulating brackets 2 at one location, the intersection 17A, which significantly reduces the number of parts, making this a more rational solution.

Next, the state of the sound-insulating fittings 2 will be explained with reference to the schematic diagram of the construction procedure for the suspended ceiling structure 1 shown in Figure 12. The suspended ceiling structure 1, which is suspended by the suspension bolts 13, which are elastic axial force members, can be represented as a model in which the suspension bolts 13 and braces 8 are set by their axial stiffness.

The state shown on the left side of Figure 12 models the state before ceiling boards 16 are attached to the siding (not shown) supported by siding support 14, which forms the ceiling substrate. Here, the overall axial stiffness of the hanging bolt 13 is set as a series connection of hanging members with axial stiffness _2k1 sandwiching a vibration-proof hanger 7 with a low axial stiffness _k3 , and the vertical component of the axial stiffness of the brace 8 is set to _k2v . Here, as shown in the enlarged view on the left, the connection between the brace 8 and the ceiling substrate is based on the presence of sound-insulating metal fittings 2.

In normal construction procedures, when ceiling panels 16 are attached to the ceiling substrate suspended from the floor slab 11 in this state and weight W is added, the ceiling substrate will sink by δ. The resistance of the suspension bolts 13 at this time is _r1 , the resistance of the vibration-isolating hangers 7 is _r3 , and the vertical component of the resistance of one brace 8 is _r2v /2.

As shown in the enlarged view on the right side of Figure 12, after the ceiling panel 16 has been attached, the state of the sound-insulating fittings 2 is such that the outer member 22 is spaced apart from the inner member 21, and only the vibration-damping material 23 can be interposed between the inner member 21 and the outer member 22. In other words, acoustic insulation is achieved between the inner member 21 and the outer member 22, and it can be said that sound insulation can be ensured by interposing the sound-insulating fittings 2 between the brace 8 and the joist support 14.

Next, an experiment conducted to confirm the sound insulation properties of the suspended ceiling structure 1 of this embodiment will be described.
The tests were carried out in a floor impact sound testing room (box-type reverberation chamber). The floor impact sound testing room is a two-story testing room separated by a 200mm thick cast-in-place concrete slab, with the test specimen placed on the lower floor (the space below the slab).

The vibration isolation performance of the ceiling is evaluated based on the damping performance of the vibration acceleration generated when the upper floor slab (corresponding to floor slab 11) is vibrated with an impact hammer. Specifically, the vertical vibration acceleration of the underside of floor slab 11 and the top surface of ceiling board 16 is measured simultaneously, and the transfer function between the two is experimentally determined for evaluation.

Vibration isolation performance is measured as the relative value of the transfer function between the two and the 1/3 octave vibration acceleration level. Figure 13 shows a model of the four evaluation specimens used in the experiment. Figure 13(a) shows a suspended ceiling structure 1 of this embodiment, in which sound-insulating fittings 2 are attached to the lower ends of the braces 8 and vibration-isolating hangers 7 are also provided on the suspension bolts 13 (evaluation specimen a: this embodiment).

Figures 13(b), (c), and (d) are evaluation test specimens for comparison. Figure 13(b) shows a suspended ceiling suspended only by suspension bolts 13 equipped with vibration-isolating hangers 7 (evaluation test specimen b: general vibration-isolating ceiling). Figure 13(c) shows a general earthquake-resistant suspended ceiling equipped with normal suspension bolts 13 and braces 8 (evaluation test specimen c: general earthquake-resistant ceiling), and Figure 13(d) shows a suspended ceiling equipped with suspension bolts 13 equipped with vibration-isolating hangers 7 and normal braces 8 (evaluation test specimen d: normal brace vibration-isolating ceiling).

Figure 14 is an explanatory diagram comparing the experimental results of evaluation specimen a (this embodiment) and evaluation specimen d (a standard braced vibration-isolation ceiling). Meanwhile, Figure 15 is an explanatory diagram comparing the experimental results of evaluation specimen b (a standard vibration-isolation ceiling) and evaluation specimen c (a standard earthquake-resistant ceiling).

The experimental results for evaluation test specimen a (this embodiment: Figure 14) and evaluation test specimen b (general vibration-isolation ceiling: Figure 15) are similar in that they both have a resonance peak at around 10 Hz. Furthermore, the experimental results for evaluation test specimen a and evaluation test specimen b show a positive acceleration level difference, and share a common frequency band where sound insulation is ensured. In other words, evaluation test specimen a can be said to have sound insulation performance on par with that of a general vibration-isolation ceiling.

On the other hand, the experimental results for evaluation specimen c (general earthquake-resistant ceiling: Figure 15) showed that the acceleration level difference was negative, particularly in the high-frequency range (for example, the range above 31.5 Hz), and sound insulation was not achieved across almost the entire range. Furthermore, the experimental results for evaluation specimen d (normally braced vibration-proof ceiling: Figure 14) showed that sound insulation was impaired in part of the high-frequency range. It is presumed that in this frequency range, the normally positioned braces 8 acted as sound bridges, compromising the effectiveness of the vibration-proof hangers 7. Furthermore, if connections were made using a method other than the sound-proofing fittings 2 of this embodiment, the braces 8 would bear a significant portion of the load of the ceiling panel 16, which would reduce the weight burden on the vibration-proof hangers and thereby reduce sound insulation performance.

Next, the operation of the sound-insulating metal fittings 2 and the suspended ceiling structure 1 of this embodiment will be described.
The sound-insulating metal fittings 2 of this embodiment configured as described above are attached to the ends of braces 8 of a suspended ceiling structure 1 having joist support portions 14 and joist portions 15 that form the ceiling substrate. That is, the inner member 21 of the sound-insulating metal fitting 2 is attached to the joist support portion 14, and the other outer member 22 is attached to the lower end of the brace 8. Then, between the inner member 21 and the outer member 22, there are provided vibration-damping materials 23 that function as sound-insulating functional parts, and spacing, or simple spacing.

In this way, if sound-insulating brackets 2 are interposed between the ends of the braces 8 and the sill support parts 14 (ceiling substrate), they can be applied to a variety of suspended ceilings, for example, where the braces 8 are placed on the ceiling substrate of a system ceiling using brackets other than the reinforcing brackets 3, making them highly versatile.

Furthermore, as mentioned above, the sound insulation performance of the sound-insulating fittings 2 and suspended ceiling structure 1 of this embodiment has been confirmed through experiments, and it can be said that the sound insulation performance of various suspended ceiling structures can be easily improved.

Furthermore, such sound-insulating metal fittings 2 can be easily manufactured by covering the shaft portion 212 formed in the center of the flat plate portion 211 with the sheath tube portion 221 and interposing vibration-damping material 23 between the shaft portion 212 and the sheath tube portion 221.

Furthermore, since the sheath tube portion 221 is provided with multiple mounting pieces 222, by interposing a sound-insulating bracket 2 at a location where braces 8 are gathered from four directions, for example, a single bracket can provide sound insulation to four braces 8.

In addition, in a suspended ceiling structure 1 suspended from a structural body such as a floor slab 11, sound insulation functionality can be easily ensured by attaching sound-insulating fittings 2 to the ends of the braces 8 connecting the floor slab 11 and the joist support 14.

In particular, when the ceiling substrate is suspended by a suspension bolt 13 equipped with an anti-vibration hanger 7, if the sound-insulating fitting 2 of this embodiment has a vibration-insulating material 23 interposed between the shaft portion 212 and the sheath tube portion 221, the brace 8 will not bear the weight of the ceiling panel 16. The anti-vibration hanger 7 of the suspension bolt 13 is designed to provide sufficient sound-insulating performance even when the weight of the ceiling panel 16 is acting on it. Therefore, if a sound-insulating fitting 2 is used in which the brace 8 does not bear even a portion of the weight of the ceiling panel 16, the sound-insulating performance of the anti-vibration hanger 7 can be fully demonstrated.

Furthermore, by attaching sound-insulating brackets 2 to the intersection 17A via reinforcing brackets 3, the braces 8 are connected to the intersection 17A via the reinforcing brackets 3, improving earthquake resistance. Furthermore, the sound-insulating brackets 2 are interposed between the vibrations of the braces 8 and the ceiling panel 16, ensuring sound insulation.

In other words, simply by attaching reinforcing metal fittings 3 to the intersection 17A between the siding support portion 14 and the siding portion 15 and connecting each of the four braces 8 to the reinforcing metal fittings 3 via sound-insulating metal fittings 2, earthquake resistance and sound insulation can be efficiently improved. Furthermore, experiments have confirmed that sufficient earthquake resistance and sound insulation can be ensured.

The following describes another use of the sound-insulating metal fittings 2 of the above-described embodiment. Note that the same or equivalent parts as those described in the above embodiment will be described using the same terms or symbols.

In the above embodiment, we have described the case where sound-insulating metal fittings 2 are attached to the lower ends of the braces 8, but this is not limited to this. For example, it can also be used as in the suspended ceiling structure 1A shown schematically in Figure 16. That is, in the suspended ceiling structure 1A of Example 1, the sound-insulating metal fittings 2 are interposed when the upper ends of the braces 8 are fixed to the tops of the suspension bolts 13 on the structural body side. With this arrangement, the suspension bolts 13 can also be repurposed as the shaft portions 212 of the sound-insulating metal fittings 2.

In this way, sound insulation between the upper and lower floors can be ensured simply by placing sound-insulating metal fittings 2 on one end of the brace 8, which transmits vibrations and sound. Furthermore, the brace to which the sound-insulating metal fittings 2 can be attached is not limited to those arranged in a V-shape, but may also be a brace that is a single diagonal member or a brace arranged in an X-shape.
The other configurations and effects are substantially the same as those of the above embodiment, and therefore the description thereof will be omitted.

The above describes in detail the embodiments and examples of the present invention with reference to the drawings, but the specific configuration is not limited to these embodiments or examples, and design changes that do not deviate from the gist of the present invention are included in the present invention.

For example, in the above embodiment, the inner member 21 is the first member and the outer member 22 is the second member, but this is not limited to this. The inner member 21 can also be the second member fixed to a brace 8 or the like, and the outer member 22 can be the first member fixed to a floor slab 11 or the like.

In addition, in the above embodiment, an attachment piece 222 for connecting the end of the brace 8 to the corner of the sheath tube portion 221 was described, but this is not limited to this, and the side edge of the attachment piece can also be fixed to the side of the sheath tube portion.

Furthermore, in the above embodiment, a configuration in which the rectangular parallelepiped shaft portion 212 is surrounded by a rectangular cylindrical sheath tube portion 221 is described, but this is not limited to this, and a configuration in which a cylindrical or polygonal prism-shaped shaft portion is surrounded by a cylindrical or polygonal tubular sheath tube portion may also be used.

Furthermore, in the above embodiment, a configuration was described in which vibration-damping material 23 is interposed between the outer peripheral surface of the shaft portion 212 and the inner peripheral surface of the sheath tube portion 221, but this is not limited to this, and there may simply be an air gap between the outer peripheral surface of the shaft portion and the inner peripheral surface of the sheath tube portion.

1, 1A: Suspended ceiling structure 11: Floor slab (structure)
13: Hanging bolt 14: Rafter support (ceiling base)
15: Rough edge (ceiling base)
2: Sound-insulating metal fitting 21: Inner member (first member or second member)
211: Flat plate portion 212: Shaft portion 22: Outer member (second member or first member)
221: sheath tube portion 222: mounting piece 23: vibration-proof material (sound-insulating functional portion)
8: Brace (diagonal member)

Claims (4)

In a suspended ceiling structure having a ceiling substrate suspended from a structural body via a suspension bolt equipped with an anti-vibration hanger, a sound-insulating metal fitting is attached to the lower end of a diagonal member whose upper end is fixed to the upper part of the suspension bolt,
A first member fixed to the ceiling substrate;
a second member fixed to a lower end of the diagonal member;
a sound-insulating function portion interposed between the first member and the second member,
The first and second members are formed such that one is columnar and the other is cylindrical and surrounds the first, and a vibration-damping material that serves as the sound-insulating functional part is interposed between them, so that the weight of the ceiling panel attached to the ceiling substrate is borne by the hanging bolt equipped with the vibration-damping hanger, which has an overall axial rigidity higher than the axial rigidity of the vibration-damping material, causing the first member to sink below the second member. One of the first member and the second member has a shaft portion formed in a columnar shape at the center of a flat plate portion, and the other has a sheath tube portion formed in a cylindrical shape surrounding the periphery of the shaft portion,
2. The sound-insulating metal fitting according to claim 1, wherein a vibration-isolating rubber is interposed between the outer peripheral surface of the shaft portion and the inner peripheral surface of the sheath tube portion, and acoustic insulation is provided between the flat plate portion and the end face of the sheath tube portion. A sound-insulating fitting as described in claim 2, characterized in that the sheath tube portion is provided with mounting pieces for connecting the lower ends of multiple diagonal members. A suspended ceiling structure having a ceiling substrate suspended from a structural body via suspension bolts equipped with vibration-isolating hangers,
The sound-insulating metal fitting according to any one of claims 1 to 3,
a diagonal member having a lower end fixed to the sound-insulating metal fitting,
The structure and the ceiling underlayment are connected via the hanging bolt, the diagonal member whose upper end is fixed to the top of the hanging bolt, and the sound-insulating metal fittings,
A suspended ceiling structure characterized in that the first member sinks more than the second member as the weight of the ceiling panel attached to the ceiling substructure is borne by the hanging bolt equipped with the vibration-damping hanger, whose overall axial rigidity is higher than the axial rigidity of the vibration-damping material.