Acoustic enclosure with back to back loudspeakers

Abstract

Acoustic enclosure (10) comprising a box (15) carrying two loudspeakers (26, 27) arranged head-to-tail and rigidly linked to each other, characterized in that it comprises, on the one hand, a single tie rod (40) connecting the two loudspeakers with two rigging ends, by complementary shape, each cooperating with a loudspeaker (26, 27), the two ends being fixed to each other in rotation around the axis (XX) of the tie rod (40) and, on the other hand, an axial stop (50, 55) between the tie rod (40) and each loudspeaker.

Description

[0001] The invention relates to an acoustic enclosure of the type comprising a box carrying two loudspeakers arranged head-to-tail and rigidly linked to each other.

[0002] The speakers dedicated to low frequencies are large and heavy components, capable of causing significant vibrations in the speaker enclosure. Therefore, they are arranged end-to-end so that the vibrations generated by one cancel out those generated by the other.

[0003] To protect these speakers and ensure proper sound propagation, an enclosure surrounds them, providing a rigid frame and acoustic insulation. These enclosures are heavy, being made of a resistant material such as metal. Connecting the two speakers and securing them within the enclosure is a complex process.

[0004] Solutions are described for example in document FR 3 087 067. US 7 062 054 B2 (D1) and US 2021 / 243520 (D2) also describe acoustic enclosures.

[0005] In figures 8 to 10, the two loudspeakers are attached by securing them to a central core.

[0006] A first speaker is screwed through the central core, the screw being received in the fixed structure of the speaker.

[0007] The second speaker has a flanged ring on its rear face, held in place by a screw. The central core includes a support block in which the flanged ring is held by two pins engaged transversely to the axis of the two speakers.

[0008] This arrangement allows for the mounting and dismounting of the speakers from a radial opening provided in the cabinet between the two speakers.

[0009] However, this device is heavy, and this is not suitable in certain areas of use where weight reduction is an objective, such as the automotive industry.

[0010] The invention aims to provide a lightweight acoustic enclosure.

[0011] For this purpose, the invention relates to an acoustic enclosure according to claim 1.

[0012] Depending on embodiments, the enclosure is according to any one of claims 2 to 6.

[0013] The invention also relates to an assembly method according to claim 7.

[0014] According to one embodiment, the method is according to claim 8.

[0015] The invention will be better understood upon reading the following description, given solely by way of example and made with reference to the drawings in which: [ Fig 1 ] there figure 1 is a perspective view of the acoustic enclosure in cross-section along a median longitudinal plane; [ Fig 2 ] there figure 2 is an exploded, perspective view of the acoustic enclosure shown on the figure 1 ; And [ Fig 3 ] there figure 3 is a partial perspective view of the acoustic enclosure, of the figures 1 And 2 , from an axial end of the enclosure carrying a loudspeaker.

[0016] The acoustic enclosure 10 shown on the figures 1 And 2 includes a cylindrical box with a circular cross-section 15 of axis XX made of plastic, defining two axial end openings 20, 25. The acoustic enclosure 10 includes two loudspeakers 26, 27 arranged head-to-tail along the axis XX and mounted in the two openings 20, 25. Alternatively, the shape of the box 15 is parallelepiped.

[0017] The box 15 includes a cylindrical skirt 31 partially closed at one end by a circular rim 32 made of the same material as the skirt and delimiting the speaker reception opening 20.

[0018] The two loudspeakers 26 and 27 are identical and each comprises a rigid basket 33 supporting a movable diaphragm 34. The loudspeaker includes a motor 35 having a magnetic circuit 36 ​​located at the bottom of the basket 33 and forming with it the fixed structure of the loudspeaker. The motor also includes a voice coil attached to the diaphragm 34.

[0019] The rigid bowl 33 has around its perimeter around the membrane 34 a peripheral fixing collar 37 with holes to accommodate screws.

[0020] The acoustic enclosure includes a unique 40 tie rod suitable for linking the fixed structures of the two speakers together.

[0021] As seen on the figure 1 , the tie rod 40 extending along the axis XX is a threaded rod, and carries two nuts 50, 55 serving as stops to rigidly link the two speakers 26, 27 together.

[0022] The single tie rod 40 has one end screwed into a tapped hole 56 provided axially on the fixed structure of the loudspeaker 26. The nut 50 is screwed against the loudspeaker 26 to prevent any movement of the loudspeaker 26 along the single tie rod 40.

[0023] The second end of the single tie rod 40 is screwed into a tapped hole 57 made at the rear of the speaker 27 with the nut 55 tightened against the fixed structure of the speaker 27.

[0024] Bolts 60 connect the loudspeaker 26 to the circular rim 32 of the enclosure 15. These bolts include a screw engaged from inside the enclosure 15 through aligned holes in the rim 32 and the peripheral collar 37 of the loudspeaker 26. The head of the screw is rotationally retained in a recess of complementary shape in the rim 32. A nut tightened from outside the loudspeaker 26 secures the connection.

[0025] An intermediate ring 65 is interposed between the box 15 and the speaker 27 to allow the angular positioning of the speaker 27 relative to the box.

[0026] This ring 65 extends the cylindrical skirt 31 of the enclosure 15 and extends radially inwards. It internally defines a circular opening 70 for receiving the loudspeaker 27. This circular opening 70 is the same size as the opening 20 for receiving the loudspeaker 26. The ring 65 has two concentric rings of holes to accommodate screws for attaching it to the enclosure 15 and the loudspeaker 27.

[0027] An outer ring is located on the flat face of the ring 65 along the outer edge, extending from the outer edge of the housing 15 on the side of the opening 25. The holes in this outer ring are peripheral slots 75 positioned in the thickness of the ring 65 and extending from the housing 15, visible on the figure 3 .

[0028] The slots each extend over approximately 5° of arc and are separated by a bridge extending over less than 1° of arc. They therefore cover most of the crown.

[0029] The inner ring is located on a circle of smaller diameter corresponding to the diameter of the circle of screw holes of the peripheral mounting collar 37 of the speaker 27.

[0030] The speaker 27 is connected to the ring 65 by bolts 80. The screw heads are rotationally secured in a recess of complementary shape in the ring. The screws are oriented from the inside of the ring 65 towards the outside of the speaker 27. The nuts are positioned from the outside face of the speaker 27.

[0031] The ring 65 and the loudspeaker 27 form a rotating assembly 85. Bolts 90 connect it to the housing 15. These bolts are placed in the slots of the outer ring of the ring and hold the rotating assembly 85 to the housing 15 with nuts held in notches 95 opening onto the cylindrical outer surface of the housing 15.

[0032] The box 15 has an opening 96 in a direction orthogonal to the axis XX. This opening 96 is wide enough to allow the passage of a tool for tightening the nuts 50, 55 on the tie rod 40.

[0033] A mounting bracket 100 is screwed onto this opening 96 by bolts 105. The mounting bracket 100 is designed to ensure the connection of the enclosure to the body of a motor vehicle.

[0034] The assembly of the acoustic enclosure 10 will now be briefly described, with reference to the figure 2 .

[0035] The speaker 26 is mounted on the enclosure 15 by placing screws 60 into the smooth holes of the circular rim 32, passing through the inside of the enclosure 15. These screws fix the speaker 26 to the enclosure by securing them with nuts from the outside of the speaker 26.

[0036] The tie rod 40 is screwed into the tapped hole 56 of the speaker 26 through the opening 25 in the enclosure 15. The tie rod carries the two nuts 50 and 55, which were previously fitted. The first nut 50 is tightened against the bottom of the speaker basket 33, thus preventing the tie rod 40 from rotating.

[0037] The speaker 27 is fixed to the ring 65 by placing the bolts 80.

[0038] The rotating assembly 85, formed by the loudspeaker 27 and the ring 65, is then screwed onto the tie rod 40. The tie rod 40, remaining stationary due to the nut 50, is inserted into the threaded hole 57 of the loudspeaker 27 by the latter's rotation. The rotating assembly 85 continues to turn until the ring 65 rests against the housing 15.

[0039] The nuts are placed in the notches 95 to securely hold the screws thus linking the rotating assembly 85 to the housing 15.

[0040] The screws 90 are inserted into the peripheral slots 75, the length of which allows the screws 90 to be aligned with the associated holes in the housing 15. If alignment is impossible, the rotating assembly 85 is turned a few more degrees to ensure that the peripheral slots 75 are opposite the holes in the housing 15. The screws 90 are tightened.

[0041] Nut 55 is tightened until it comes to a stop against the bottom of the speaker bowl 33 27, passing through the opening 96.

[0042] The electrical connections between the two speakers 26 and 27 are made once the two speakers are rigidly connected to each other, limiting the impact of the rotation of speaker 27 on the electronic coupling of the two speakers. The screws forming part of the bolts 105 are installed along the opening 96 before the latter is closed.

[0043] The opening 96 is obstructed by the fixing bracket 100 using the bolts 105 and tightening the corresponding nuts.

[0044] For the dismantling of the acoustic enclosure 10, the reverse procedure is used.

[0045] The acoustic enclosure 10 has the advantage of being compact, simple to assemble and disassemble and does not require glue or other chemical elements.

Claims

1. Acoustic enclosure (10) comprising a casing (15) containing two loudspeakers (26, 27) arranged back to back and rigidly connected to each other, characterised in that it comprises, on the one hand, a single tie rod (40) for connecting the two loudspeakers with two hooking ends, each cooperating in a form-fitting manner with one loudspeaker (26, 27), the two ends being integral with each other in rotation around the axis (X-X) of the tie rod (40) and, on the other hand, an axial stop (50, 55) between the tie rod (40) and each loudspeaker (26, 27), in which the tie rod (40) has a threaded rod, characterised in that each stop comprises a nut (50, 55) mounted on the threaded rod and supported on each loudspeaker (26, 27).

2. Acoustic enclosure (10) according to claim 1, in which each loudspeaker (26, 27) is connected to the casing (15).

3. Acoustic enclosure (10) according to claim 2, comprising, at least for one loudspeaker, an intermediate ring (65) provided with a set of peripheral slots (75) interposed between the loudspeaker (27) and the casing (15), and screws (90) for retaining the ring (65) on the casing (15) engaged in the set of slots (75), the loudspeaker (27) being secured to the ring (65).

4. Acoustic enclosure (10) according to any one of the preceding claims, in which the casing (15) is made of plastic.

5. Acoustic enclosure (10) according to any one of the preceding claims, in which the casing (15) defines an opening (96) providing access to the tie rod (40).

6. Acoustic enclosure (10) according to claim 5, in which a console (100) obstructs access to the opening (96).

7. Assembly method for the acoustic enclosure (10) according to any one of the preceding claims, said method comprising: - fixing a first loudspeaker (26) to the casing (15); - fixing the tie rod (40) to the rear of the first loudspeaker (26); and - fixing the rear of the second loudspeaker (27) to the tie rod (40), when mounting the second loudspeaker (27) on the casing.

8. Assembly method according to claim 7, of the acoustic enclosure (10) according to claim 3, said method further comprising: - fixing the second loudspeaker (27) to the ring (65) to form a rotary assembly (85); - fixing the rear of the second loudspeaker (27) to the tie rod (40) when mounting the rotary assembly (85) comprising the second loudspeaker (27) on the casing (15); and - fixing the rotary assembly (85) to the casing (15) by inserting the retaining screws (90) in the peripheral slots (75) of the ring (65).

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