FR3097397A1 - Simplified acoustic enclosure - Google Patents

Abstract

Simplified acoustic enclosure Acoustic enclosure (1) comprising: - a box (5) comprising a wall (42) visible at least in part from outside the acoustic enclosure, and a fixing part (44) fixed to the visible wall , - at least one loudspeaker (10) fixed to the fixing part, the loudspeaker defining an axis (D) and comprising a magnetic circuit (18), and a movable assembly (22) mounted movable axially relative to the magnetic circuit around a position of equilibrium, the mobile assembly comprising a membrane (32) adapted to emit sound waves, the membrane defining a front side of the loudspeaker, - a first suspension joint (14) comprising a first end (50) radially inner fixed to the moving assembly, and - a second suspension joint (16) comprising a first end (56) attached to the moving assembly, the moving assembly, the casing and the first gasket suspension defining at least in part an internal volume confined air chamber (26). The first suspension joint comprises a second radially outer end (52) fixed to said visible wall. The second suspension joint has a second end (58) fixed to the box. Figure for the abstract: Figure 1

Description

Simplified acoustic enclosure

The present invention relates to an acoustic enclosure comprising:

- a box comprising a wall visible at least in part from the outside of the acoustic enclosure, and a fixing part fixed to the visible wall;

- at least one loudspeaker located in an opening defined by the casing, and fixed to the fixing part, the loudspeaker defining an axis and comprising a magnetic circuit, and a mobile assembly mounted mobile axially with respect to the magnetic circuit around from a position of equilibrium, the moving assembly comprising a membrane suitable for emitting sound waves, the membrane defining a front side of the loudspeaker along the axis;

- a first suspension joint comprising a first radially inner end fixed to the moving assembly; And

- a second suspension joint comprising a first end fixed to the moving assembly,

the moving assembly, the box and the first suspension joint defining at least in part an interior volume of confined air.

The loudspeaker also includes a chassis, also called a “salad bowl” because of its flared shape. The magnetic circuit is fixed to the chassis, and the two suspension joints connect the moving assembly to the chassis.

The chassis serves as a support for all the other elements of the loudspeaker, and is itself fixed to the box or to an internal structure integral with the box. In addition to its function as a chassis, the salad bowl also makes it easy to handle the loudspeaker and to fix it to the box.

In order to guarantee good acoustic quality of the loudspeaker, the membrane has a certain surface. It is also important that the volume of air trapped under the membrane inside the acoustic enclosure is as large as possible. To do this, the frame is generally perforated, that is to say it has openings allowing air to circulate between the space between the membrane and the frame on the one hand, and between the chassis and the box on the other hand.

In order to reduce costs, it is desirable to reduce the external volume of the acoustic enclosure, but this reduction comes up against the aforementioned constraints of maintaining a sufficient membrane surface and internal air volume.

An object of the invention is therefore to provide an acoustic enclosure whose manufacturing cost is reduced, while preserving its acoustic quality.

To this end, the subject of the invention is an acoustic enclosure of the above type, in which

- the first suspension seal comprises a second radially outer end fixed to said visible wall; And

- The second suspension joint comprises a second end fixed to the box.

According to particular embodiments, the acoustic enclosure comprises one or more of the following characteristics, taken separately or in all technically possible combinations:

- the fixing part is made in one piece with the visible wall;

- the magnetic circuit is fixed, preferably directly, on the fixing part;

- The fixing part defines said opening and forms an extension of the visible wall in the interior volume, the second end of the second suspension joint being fixed on the fixing part;

- the fixing part has a flared shape along the forward axis;

- the fixing part comprises a fixing portion extending in a plane perpendicular to the axis, the magnetic circuit being fixed on the fixing portion;

- the fixing part comprises a protuberance extending from the fixing portion towards the membrane, the second end of the second suspension joint being fixed on the protuberance;

- the protuberance is annular and centered on the axis;

- the fixing portion comprises a plate, and an area axially thicker than the plate, the loudspeaker comprising at least one fixing screw screwed into the axially thicker area; And

- the loudspeaker does not have a part fixed to the magnetic circuit and widening axially towards the front in the interior volume.

The invention will be better understood on reading the following description, given solely by way of example and made with reference to the appended drawings, in which:

Figure 1 is a schematic view, in section along a plane passing through the axis of the loudspeaker, of an acoustic enclosure according to a first embodiment of the invention, and

FIG. 2 is a view similar to FIG. 1, but of a loudspeaker according to a second embodiment of the invention.

Referring to Figure 1, a loudspeaker 1 is described according to a first embodiment of the invention.

The acoustic enclosure 1 comprises a box 5 defining two openings 7 and 9, and two loudspeakers 10, 12 located in the openings 7, 9, advantageously coaxial along an axis D defined by the loudspeaker 10, and for example head - spade along this axis. The acoustic enclosure also includes a first suspension joint 14 and a second suspension joint 16.

The two loudspeakers 10, 12 are therefore angularly distributed at 180° from each other around an axis Δ perpendicular to the axis D.

According to variants not shown, the acoustic enclosure 1 comprises a single loudspeaker.

According to other variants not shown, the acoustic enclosure 1 comprises N loudspeakers, with N greater than or equal to 3. The loudspeakers are for example distributed angularly around the axis Δ, advantageously regularly, i.e. that is to say that they form between them angles of 360°/N.

In the example shown, the acoustic enclosure 1 is substantially symmetrical with respect to a plane P perpendicular to the axis D. Also, the loudspeaker 12 and its connection with the box 5 will not be described in detail below. .

The loudspeaker 10 and the box 5 are for example substantially of revolution around the axis D.

The loudspeaker 10 comprises a magnetic circuit 18 defining an air gap 20, and a mobile assembly 22 mounted to move axially with respect to the magnetic circuit around an equilibrium position shown in FIG. 1.

Loudspeaker 10 does not have a basket which would be materially distinct from box 5.

The magnetic circuit 18 is directly fixed on an edge 24 of the box defining the opening 7.

The moving assembly 22, the box 5 and the first suspension joint 14 define with the loudspeaker 12 an interior volume 26 of confined air.

The moving assembly 22 comprises a coil 28 located in the air gap 20, a coil carrier 30 on which the coil is fixed, a membrane 32 fixed to the coil carrier and adapted to emit sound waves, and a core cover 34 attached to the membrane.

The membrane 32 defines with respect to the magnetic circuit 18 a front side of the loudspeaker 10 along the axis D. The membrane extends for example radially from the coil holder 30. The membrane is for example of generally flared shape towards the front, advantageously tapered.

According to a variant not shown, the membrane is spherical, the convexity of the membrane being advantageously facing forwards. In this case, the membrane is located in front of the spool holder and the core cover 34 is not present.

The spool holder 30 is for example cylindrical with an axis D. The spool holder is advantageously fixed to the membrane 32. The spool holder 30 advantageously has openings (not shown) to allow air to circulate freely between its side radially interior and its radially exterior side in the interior volume 26.

The core cover 34 makes it possible to hide the coil carrier 30 and the magnetic circuit 18 from the view of a user of the acoustic enclosure 1. The core cover is for example spherical, its convexity facing forwards.

The box 5 comprises for example a middle part 36 crossed by the plane P, a front part 38, and a rear part 40 symmetrical to the front part with respect to the plane P.

The middle part 36 is for example made of thermoplastic material.

The front part 38 is for example made of sheet steel.

The front part 38 comprises a wall 42 visible from the outside of the acoustic enclosure, and a fixing part 44 integral with the wall 42 and fixed to the magnetic circuit 18.

In the example shown, the fixing part 44 forms an extension of the wall 42 in the interior volume 26. The fixing part is not visible from the outside of the acoustic enclosure.

The fixing part advantageously defines one or more openings 46 suitable for allowing air to circulate freely inside the interior volume 26.

A passage 48 is advantageously made in the magnetic circuit 18 to allow air to pass axially within the interior volume 26.

The first suspension joint 14 has, for example, a "U"-shaped radial section, the base of the "U" being advantageously directed forwards. The first suspension joint comprises a first radially inner end 50 fixed to the mobile assembly 22, for example to the membrane 32, and a second radially outer end 52 fixed to the wall 42 of the casing 5, and not to a salad bowl as in conventional loudspeakers.

The second end 52 is advantageously fixed to a flat zone 54 of the wall 42, the flat zone being in the example shown substantially perpendicular to the axis D.

The second suspension joint 16 is advantageously of a type known in itself under the name of “spider”. The second suspension joint comprises a radially inner first end 56 fixed to the moving assembly, for example to the reel holder 30, and a radially outer second end 58 fixed to the fixing part 44.

To mount the acoustic enclosure 1, the magnetic circuit 18 is first mounted on the fixing part 44. Then the mobile assembly 22, without the core cover 34 is introduced into the air gap and the two seals are fixed on the fixed part 44. Then the core cover 34 is fixed on the membrane 32.

Finally, the first suspension joint 14 is fixed on the one hand to the fixing member 34, and on the other hand to the wall 42.

When the acoustic enclosure 1 is in operation, the air trapped in the interior volume 26 circulates freely radially through the spool holder 30, and axially via the passage 48.

Thanks to the characteristics described above, allowing the absence of a salad bowl, the acoustic enclosure 1 comprises fewer parts and is therefore relatively less expensive than in the state of the art. The dimensions of the membrane 32 and the interior volume 26 are at least preserved, which maintains the acoustic quality of the enclosure.

Referring to Figure 2, we will now describe a loudspeaker 100 according to a second embodiment of the invention. The acoustic enclosure 100 is similar to the acoustic enclosure 1 represented in FIG. 1. Similar elements bear the same reference numerals and will not be described again. Only the differences will be described in detail below.

The opening 7 in which the loudspeaker 10 is located is defined by the visible wall 42 of the box 5, and not by an edge 24 of the fixing part 44.

In the example shown, the moving assembly 22 does not include a core cover.

The membrane 32 is substantially planar. The membrane is adapted to hide the spool holder 30 and the magnetic circuit 18.

The moving assembly comprises a connecting member 135 extending axially towards the rear from the membrane 32. The connecting member 135 advantageously defines openings 146 to allow the passage of air radially within the interior volume. 26.

The radially inner end 56 of the first suspension joint 16 is fixed to the connecting member 135.

The first suspension joint 14 also has a "U" shape, but the base of the "U" is advantageously directed rearward. The second radially outer end 52 of the first suspension joint is for example fixed on an edge 154 defined by the wall 42 of the box 5.

The box 5 is advantageously made in one piece, for example of thermoplastic material.

The fixing part 44 comprises a fixing portion 144 extending in the plane P, and a protuberance 146 extending axially from the fixing portion towards the membrane 32 and on which the second end 58 of the second suspension joint 16 is fixed.

The protuberance 146 is for example annular and advantageously centered on the axis D.

The fixing portion 144 comprises for example a plate 148, and a zone 150 axially thicker than the plate.

The loudspeaker 10 is fixed to the fixing part 44 using a screw 152 screwed into the axially thicker area 150 through the magnetic circuit 18.

As can be seen, the acoustic enclosure 100 is devoid of any part fixed to the magnetic circuit 18 and widening axially forwards in the interior volume 26, that is to say devoid of a salad bowl.

In the acoustic enclosure 100, the magnetic circuit 18 is therefore fixed from behind to the fixing part 44, which does not define the opening 7 in which the loudspeaker 10 is arranged, whereas, in the enclosure acoustic 1, the magnetic circuit 18 is fixed from the front on a fixing part 44 which defines the opening 7.

In the acoustic enclosure 100, the attachment part 44 delimits the rear of the interior volume 26, while the attachment portion 44 of the acoustic enclosure 1 crosses part of the interior volume 26.

Obviously, intermediate embodiments between the first and second embodiments described above are possible, that is to say that the fixing part 44 can be located axially at intermediate levels between the situations represented on the figures 1 and 2.

The acoustic enclosure 100 has the same advantages as the acoustic enclosure 1.

Claims (10)

Acoustic enclosure (1; 100) comprising:
- a box (5) comprising a wall (42) visible at least in part from the outside of the acoustic enclosure (1; 100), and a fixing part (44) fixed to the visible wall (42),
- at least one loudspeaker (10; 12) located in an opening (7, 9) defined by the casing (5), and fixed to the fixing part (44), the loudspeaker (10; 12) defining an axis (D) and comprising a magnetic circuit (18), and a movable assembly (22) mounted so as to be able to move axially with respect to the magnetic circuit (18) around an equilibrium position, the movable assembly (22) comprising a membrane (32) adapted to emit sound waves, the membrane (32) defining a front side of the loudspeaker (10; 12) along the axis (D),
- a first suspension joint (14) comprising a first radially inner end (50) fixed to the moving assembly (22), and
- a second suspension joint (16) comprising a first end (56) fixed to the moving assembly (22),
the moving assembly (22), the box (5) and the first suspension joint (14) defining at least in part an interior volume (26) of confined air,
characterized in that:
- the first suspension joint (14) comprises a second radially outer end (52) fixed to said visible wall (42), and
- the second suspension joint (16) comprises a second end (58) fixed to the box. Acoustic enclosure (1; 100) according to claim 1, in which the fixing part (44) is made integral with the visible wall (42). Acoustic enclosure (1; 100) according to Claim 1 or 2, in which the magnetic circuit (18) is fixed, preferably directly, to the fixing part (44). Acoustic enclosure (1) according to any one of claims 1 to 3, in which fixing part (44) defines said opening (7, 9) and forms an extension of the wall (42) visible in the interior volume (26) , the second end (58) of the second suspension joint (16) being fixed to the fixing part (44). Acoustic enclosure (1) according to Claim 4, in which the fixing part (44) has a flared shape along the axis (D) towards the front. Acoustic enclosure (1) according to any one of Claims 1 to 3, in which the fixing part (44) comprises a fixing portion (144) extending in a plane (P) perpendicular to the axis (D) , the magnetic circuit (18) being fixed on the fixing portion (144). Acoustic enclosure (1) according to claim 6, in which the fixing part (44) comprises a protrusion (146) extending from the fixing portion (144) towards the membrane (32), the second end (58) of the second suspension joint (16) being fixed on the protrusion (146). Acoustic enclosure (100) according to claim 7, in which the protuberance (146) is annular and centered on the axis (D). Acoustic enclosure (100) according to any one of claims 6 to 8, in which the fixing portion (144) comprises a plate (148), and an area (150) axially thicker than the plate (148), the top -loudspeaker (10; 12) comprising at least one fixing screw (152) screwed into the axially thicker zone (150). Acoustic enclosure (100) according to any one of Claims 1 to 9, in which the loudspeaker (10, 12) does not have a part fixed to the magnetic circuit (18) and widening axially towards the front in the interior volume (26).