Acoustic shutter assembly

Abstract

The acoustic shutter assembly (1) includes at least one window pane (2, 3) arranged in a frame (4). At least one ventilation duct (7) is arranged in the frame between an outer ventilation opening (8) and an inner ventilation opening (9), extending between a first layer of sound absorbing material arranged at an inside (5) and a second layer of sound absorbing material arranged at an outside. A number of acoustic reflectors (12) in the form of plate material are arranged between the first and second layers of sound absorbing material so that the ventilation duct is separated into a number of respective ventilation channels (13) formed between the acoustic reflectors. Each ventilation channel changes direction at least once between the outer ventilation opening and the inner ventilation opening, thereby at least substantially blocking any linear path from the outer ventilation opening to the inner ventilation opening.

Claims

1. An acoustic shutter assembly adapted to cover a window opening in a wall, including at least one window pane arranged in a frame having an inside adapted to be mounted on the wall and an outside adapted to face away from the wall, wherein at least one ventilation duct is arranged in the frame between an outer ventilation opening and an inner ventilation opening, wherein the ventilation duct extends between a first layer of sound absorbing material arranged at the inside of the frame and a second layer of sound absorbing material arranged at the outside of the frame, and wherein the first and second layers of sound absorbing material extend at least substantially in parallel with the window pane, wherein a plurality of elongate acoustic reflectors are arranged between the first and second layers of sound absorbing material, wherein each of the acoustic reflectors extends across the frame from a location proximate the outer ventilation opening to a location proximate the inner ventilation opening so that the ventilation duct is separated into a number of respective ventilation channels formed between and defined at least in part by the acoustic reflectors, and further wherein each ventilation channel changes direction at least once between the outer ventilation opening and the inner ventilation opening, thereby at least substantially blocking any linear path from the outer ventilation-opening to the inner ventilation opening.

2. An acoustic shutter assembly according to claim 1, wherein the ventilation duct is lined by means of a first perforated plate covering the first layer of sound absorbing material and a second perforated plate covering the second layer of sound absorbing material so that the acoustic reflectors extend from the first perforated plate to the second perforated plate.

3. An acoustic shutter assembly according to claim 1, wherein the first layer of sound absorbing material has a first thickness (t) and the second layer of sound absorbing material has a second thickness (T), wherein the second thickness (T) is greater than the first thickness (t).

4. An acoustic shutter assembly according to claim 3, wherein the second thickness (T) is at least 4/3 the first thickness (t).

5. An acoustic shutter assembly according to claim 3, wherein the second thickness (T) is at least 3/2 the first thickness (t).

6. An acoustic shutter assembly according to claim 3, wherein the second thickness (T) is at least double the first thickness (t).

7. An acoustic shutter assembly according to claim 1, wherein each acoustic reflector is V-formed with a first leg extending obliquely towards the outer ventilation opening and a second leg extending obliquely towards the inner ventilation opening, and wherein the first and second leg of each acoustic reflector connect about midway between the outer ventilation opening and the inner ventilation opening in a top point of the acoustic reflector.

8. An acoustic shutter assembly according to claim 1, wherein each outer ventilation opening is covered by a filter in the form of a perforated plate.

9. An acoustic shutter assembly according to claim 1, wherein the at least one ventilation duct is formed in an absorption module including a first absorption cassette holding the first layer of sound absorbing material and a second absorption cassette holding the second layer of sound absorbing material, and wherein each absorption cassette has at least two opposed U-formed profiles holding opposed edges of the corresponding layer of sound absorbing material.

10. An acoustic shutter assembly according to claim 1, wherein the frame has four frame members in the form of a top member, a bottom member, a first side member and a second side member, wherein a first ventilation duct is arranged at the first side member and a second ventilation duct is arranged at the second side member.

11. An acoustic shutter assembly according to claim 10, wherein a first shutter is arranged in an open position at the first side member and a second shutter is arranged in an open position at the second side member, and wherein the first and second shutters are arranged displaceably to respective closed positions thereby covering the at least one window pane.

12. An acoustic shutter assembly according to claim 11, wherein a plurality of pane parts are arranged displaceably in a plane extending between a plane of the first and second layers of sound absorbing material and a plane in which the first and second shutters are arranged displaceably.

13. An acoustic shutter assembly according to claim 11, wherein the at least one window pane is separated in a first pane part arranged in an open position at the first side member and a second pane part arranged in an open position at the second side member, and wherein the first and second pane parts are arranged displaceably to respective closed positions in which the first and second pane parts meet each other and covers the window opening.

14. An acoustic shutter assembly according to claim 13, wherein the pane parts are arranged displaceably in a plane extending between a plane of the first and second layers of sound absorbing material and a plane in which the first and second shutters are arranged displaceably.

15. An acoustic shutter assembly according to claim 10, wherein the at least one window pane is separated in a first pane part arranged in an open position at the first side member and a second pane part arranged in an open position at the second side member, and wherein the first and second pane parts are arranged displaceably to respective closed positions in which the first and second pane parts meet each other and covers the window opening.

16. An acoustic shutter assembly according to claim 1, wherein at least one of the acoustic reflectors is curved from the outer ventilation opening to the inner ventilation opening to at least partially block the linear path from the outer ventilation-opening to the inner ventilation opening through at least one of the ventilation channels.

17. The acoustic shutter assembly according to claim 16, wherein the at least one acoustic reflector is curved into an arcuate shape.

18. An acoustic shutter assembly according to claim 1, wherein at least one of the acoustic reflectors is formed from a single piece of material extending across the frame.

19. An acoustic shutter assembly according to claim 1, wherein at least one of the acoustic reflectors is formed from a plurality of flattened planar segments.

20. An acoustic shutter assembly according to claim 1, wherein at least one of the acoustic reflectors extends fully across the frame from the outer ventilation opening to the inner ventilation opening.

Description

(1) The invention will now be explained in more detail below by means of examples of embodiments with reference to the very schematic drawing, in which

(2) FIG. 1 is a perspective view of an acoustic shutter assembly according to the invention, seen from the outside of the assembly, and with the right shutter and the outside of the right absorption module removed for illustration purposes;

(3) FIG. 2 is front view of the acoustic shutter assembly of FIG. 1, seen from the outside of the assembly, and with part of the right shutter and part of the outside of the right absorption module removed for illustration purposes;

(4) FIG. 3 is a cross-section along the line III-III of FIG. 2;

(5) FIG. 4 is a front view of an absorption module of the acoustic shutter assembly of FIG. 1, without the first and second layers of sound absorbing material;

(6) FIG. 5 is a side view of the absorption module of FIG. 4, seen from the right;

(7) FIG. 6 is a cross-section along the line VI-VI of FIG. 5;

(8) FIG. 7 is a partial cross-section along the line VII-VII of FIG. 4, seen on a larger scale and illustrating top and bottom parts of the absorption module;

(9) FIG. 8 is a top view of the absorption module of FIG. 4, seen on a larger scale;

(10) FIG. 9 is a complete front view of the acoustic shutter assembly according to the invention, corresponding to the view of FIG. 2;

(11) FIG. 10 illustrates in part, and on a larger scale, a cross-section along the line X-X of FIG. 9;

(12) FIG. 11 is a perspective view of a top module of the acoustic shutter assembly according to the invention;

(13) FIG. 12 is the detail XII of FIG. 11 illustrated on a larger scale; and

(14) FIG. 13 is the detail XIII of FIG. 11 illustrated on a larger scale.

(15) FIG. 1 shows an embodiment of an acoustic shutter assembly 1 according to the present invention adapted to cover a window opening in a not shown wall. The acoustic shutter assembly 1 includes a window pane 2, 3 arranged in a frame 4 having an inside 5 adapted to be mounted on the not shown wall and an outside 6 adapted to face away from said wall. The frame 4 has four frame members in the form of a top member 23, a bottom member 24, a first side member 25 and a second side member 26.

(16) A first ventilation duct 7 is arranged at the first side member 25 and a second ventilation duct 7 is arranged at the second side member 26. Each ventilation duct 7 is arranged in the frame 4 between an outer ventilation opening 8 and an inner ventilation opening 9, and the ventilation duct 7 extends between a first layer 10 of sound absorbing material arranged at the inside 5 of the frame 4 and a second layer 11 of sound absorbing material arranged at the outside 6 of the frame. The first and second layers 10, 11 of sound absorbing material extend at least substantially in parallel with the window pane 2, 3.

(17) A number of acoustic reflectors 12 in the form of metal plate material are arranged between the first and second layers 10, 11 of sound absorbing material so that each ventilation duct 7 is separated into a number of respective ventilation channels 13 formed between the acoustic reflectors 12. The metal plate material of each acoustic reflector 12 is V-formed with a first leg 16 extending obliquely towards the outer ventilation opening 8 and a second leg 17 extending obliquely towards the inner ventilation opening 9. Thereby, each ventilation channel 13 changes direction between the outer ventilation opening 8 and the inner ventilation opening 9, so that any linear path from the outer ventilation 8 opening to the inner ventilation opening 9 is blocked. This may of course be achieved with many other forms of the acoustic reflectors 12 than the illustrated V-form. For instance, the acoustic reflectors 12 could form an arc. In the illustrated embodiment, the first and second legs 16, 17 of each acoustic reflector 12 connect midway between the outer ventilation opening 8 and the inner ventilation opening 9 in a top point 18 of the acoustic reflector 12. As illustrated in FIG. 10, each outer ventilation opening 8 is covered by a filter 19 in the form of a perforated plate.

(18) Each ventilation duct 7 is lined by means of a first perforated plate 14 covering the first layer 10 of sound absorbing material and a second perforated plate 15 covering the second layer 11 of sound absorbing material so that the acoustic reflectors 12 extend from the first perforated plate 14 to the second perforated plate 15. The acoustic reflectors 12 are welded to the first and second perforated plates 14, 15.

(19) The first and second layers 10, 11 of sound absorbing material may be made of a PET (Polyethylene terephthalate) felt or any other suitable sound absorbing material. As illustrated in FIG. 10, between the first perforated plate 14 and the first layer 10 of sound absorbing material and between the second perforated plate 15 and the second layer 11 of sound absorbing material, a sound absorbing foil 29 is arranged that may also act as a vapour barrier.

(20) According to the present invention, the first layer 10 of sound absorbing material has a first thickness t and the second layer 11 of sound absorbing material has a second thickness T, and the second thickness T is greater than the first thickness t. In the illustrated embodiment, the first thickness t is 20 millimetres and the second thickness T is 40 millimetres. In any way, according to the present invention, it may be preferred that the second thickness T is preferably at least 4/3 of, more preferred at least 3/2 of, and most preferred about the double of, the first thickness t.

(21) As illustrated in FIGS. 4 to 8, the at least one ventilation duct 7 is formed in an absorption module 20 including a first absorption cassette 21 holding the first layer 10 of sound absorbing material and a second absorption cassette 22 holding the second layer 11 of sound absorbing material. It should be noted, however, that FIGS. 4 to 8 illustrate the absorption module 20 without the first and second layers 10, 11 of sound absorbing material. As particularly well illustrated in FIG. 8, each absorption cassette 21, 22 has two opposed U-formed profiles 23 adapted to hold opposed edges of the corresponding layer 10, 11 of sound absorbing material. The U-formed profiles 23 are welded to the vertical side edges of the first and second perforated plates 14, 15. The top and bottom edges of the first and second perforated plates 14, 15 are held together at a distance from each other in that they are welded to a U-formed profile 31. The arrangement of the layers 10, 11 of sound absorbing material in the absorption cassettes 21, 22 is illustrated in FIG. 3.

(22) As seen for instance in FIG. 9, a first shutter 27 is arranged in its open position at the first side member 25 and a second shutter 28 is arranged in its open position at the second side member 26. The first and second shutters 27, 28 are arranged displaceably to respective closed positions in which the shutters abut each other centrally and the window pane 2, 3 is covered.

(23) As also seen in FIG. 9, the window pane 2, 3 is separated in a first pane part 2 which is slideable to its open position at the first side member 25 and a second pane part 3 which is slideable to its open position at the second side member 26. In the illustrated situation, the first and second pane parts 2, 3 are in their closed positions in which the first and second pane parts 2, 3 meet each other and covers the window opening. As seen in FIG. 10, the pane parts 2, 3 are arranged displaceably in a plane extending between the second layer 11 of sound absorbing material and a plane in which the first and second shutters 27, 28 are arranged displaceably. The front side of the second layer 11 of sound absorbing material is covered by means of a metal plate 30 in order to cover the outside of the sound absorbing material when the first and second shutters 27, 28 are moved to their closed positions.

(24) As illustrated in FIGS. 10 and 11, the first and second shutters 27, 28 are arranged displaceably in that a bracket 32 mounted at the upper edge of each shutter 27, 28 carries first rollers 33 rolling in a track 34 of the frame 4 and second rollers 35 running on either side of a track 36 of the frame 4. Pins 46 at the lower edge of each shutter 27, 28 steer in a groove 47 of the frame 4. The first and second shutters 27, 28 are driven by means of an electric motor 37 by means of a wire 38 driven by the electric motor 37. The wire 38 runs over a first wire roller 39 driven by the motor and a second opposed wire roller 40. The wire 38 is tensioned by means of a tensioning roller 41 held by a spring 42. The wire 38 is connected to each shutter 27, 28 by means of respective brackets 43.

(25) The first and second pane parts 2, 3 are arranged manually displaceably in that rollers 44 at the top of each pane part 2, 3 roll in a track 45 of the frame 4. A lower edge 48 of the first and second pane parts 2, 3 steers in a groove 49 of the frame 4.

LIST OF REFERENCE NUMBERS

(26) t thickness of first layer of sound absorbing material T thickness of second layer of sound absorbing material 1 acoustic shutter assembly 2 left window pane part 3 right window pane part 4 frame 5 inside of frame 6 outside of frame 7 ventilation duct 8 outer ventilation opening 9 inner ventilation opening 10 first layer of sound absorbing material 11 second layer of sound absorbing material 12 acoustic reflector 13 ventilation channel 14 first perforated plate 15 second perforated plate 16 first leg of V-formed acoustic reflector 17 second leg of V-formed acoustic reflector 18 top point of acoustic reflector 19 filter of outer ventilation opening 20 absorption module 21 first absorption cassette 22 second absorption cassette 23 top member of frame 24 bottom member of frame 25 first side member of frame 26 second side member of frame 27 first shutter 28 second shutter 29 sound absorbing foil 30 metal plate 31 U-formed profile 32 bracket 33 first roller 34 track of frame 35 second rollers 36 track of frame 37 electric motor 38 wire 39 first wire roller 40 second wire roller 41 tensioning roller 42 spring 43 brackets 44 roller of pane part 45 track of frame 46 pin of shutter 47 groove of frame 48 lower edge of pane part 49 groove of frame