ACOUSTIC PANEL ASSEMBLY WITH SUSPENSION SYSTEM

Abstract

An acoustic panel assembly has only one acoustic panel with a back surface, a frame that peripherally surrounds the acoustic panel, a support integral with the frame, only one magnetic unit fixed to said support, only a voice coil fixed to the acoustic panel, a supporting structure integral with the frame, and a plurality of springs connected to the supporting structure. The springs are connected in different points of the back surface of the acoustic panel in such a way to elastically support the acoustic panel.

Claims

1. Acoustic panel assembly comprising: only one acoustic panel with a back surface; a frame that peripherally surrounds the acoustic panel; a support integral with the frame; only one magnetic unit fixed to said support; only one voice coil fixed to said acoustic panel; and a supporting structure integral with the frame; characterized in that it comprises: a plurality of springs connected to said supporting structure, said springs being connected in different points of the back surface of the acoustic panel in such a way to elastically support the acoustic panel.

2. The acoustic panel assembly of claim 1, wherein said supporting structure is shaped as a grill with a plurality of openings and said springs are disposed in at least some of said openings of the supporting structure.

3. The acoustic panel assembly of claim 2, wherein said openings of the supporting structure are disposed according to a pattern of lines and columns, all openings have the same dimensions, the magnetic unit is disposed in one of said openings and the springs are disposed in the remaining openings.

4. The acoustic panel assembly of claim 2, wherein said support of the magnetic unit is integral with the supporting structure and said magnetic unit is disposed in one of said openings of the supporting structure.

5. The acoustic panel assembly of claim 1, wherein said springs are integrally made in one piece with said supporting structure.

6. The acoustic panel assembly of claim 1, wherein each spring comprises damping means that comprise dampers made of a soft, elastic material, which are disposed above and under the spring.

7. The acoustic panel assembly of claim 1, wherein each spring comprises: a central portion fixed to the acoustic panel; two peripheral portions fixed to the support structure in diametrically opposite positions relative to the central portion; and two arms with a curved shape that connect the central portion with the peripheral portions.

8. The acoustic panel assembly of claim 1, wherein each spring comprises a centering device or spider having a disc-like shape with wavy cross-section, with a central portion fixed to the support structure and a peripheral annular portion fixed to the acoustic panel.

9. The acoustic panel assembly of claim 1, wherein said supporting structure comprises a plurality of rectilinear elastic tabs that act as springs, which protrude from the supporting structure and have one end fixed to the acoustic panel.

10. Acoustic panel assembly comprising: only one acoustic panel with a back surface; a frame that peripherally surrounds the acoustic panel; a support integral with the frame; only one magnetic unit fixed to said support; and only one voice coil fixed to said acoustic panel; characterized in that it comprises: a plurality of springs connected to said frame, said springs being connected in different points of the back surface of the acoustic panel in such a way to elastically support the acoustic panel.

11. The acoustic panel assembly of claim 10, wherein said frame comprises elastic tabs, which act as springs, protruding from the frame towards the acoustic panel and behind the acoustic panel, each elastic tab, which acts as spring, has a wavy shape and a planar ending section fixed to the acoustic panel.

12. Acoustic panel assembly comprising: only one acoustic panel with a back surface; a frame that peripherally surrounds the acoustic panel; a support integral with the frame; only one magnetic unit fixed to said support; and only one voice coil fixed to said acoustic panel; characterized in that: said frame is provided with through notches in such a way to obtain a plurality of elastic arms acting as springs that elastically connect a peripheral portion of the frame to a central portion of the frame fixed to the acoustic panel.

13. Acoustic panel assembly comprising: only one acoustic panel with a back surface; a frame that peripherally surrounds the acoustic panel; a support integral with the frame; only one magnetic unit fixed to said support; and only one voice coil fixed to said acoustic panel; characterized in that: said acoustic panel is provided with through notches in peripheral position in such a way to obtain a plurality of elastic arms acting as springs that elastically connect a central portion of the acoustic panel and a peripheral portion of the acoustic panel fixed to the frame.

14. Use of the acoustic panel assembly according to claim 3, wherein each spring is connected to a dynamometer to measure the force exerted on each spring during the operation of the acoustic panel assembly, in such a way to eliminate some springs or change the elasticity coefficient of some springs that negatively affect the operation of the acoustic panel assembly.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0031] Additional features of the invention will appear clearer from the following detailed description, which refers to merely illustrative, not limiting embodiments, which are illustrated in the appended drawings, wherein:

[0032] FIG. 1 is a sectional axial view of an acoustic panel assembly according to the prior art;

[0033] FIG. 2 is a sectional view of six types of elastic perimeter suspensions used in acoustic panels according to the prior art;

[0034] FIG. 3 is a top view of an acoustic panel assembly according to the invention;

[0035] FIG. 4 is a bottom view of the acoustic panel assembly of FIG. 3;

[0036] FIG. 5 is the same view as FIG. 4, which illustrates a variant of the supporting structure;

[0037] FIG. 6 is a plan view of a variant of a spring of the supporting structure;

[0038] FIG. 7 is an axial view taken along the sectional plane VII-VII of FIG. 7;

[0039] FIGS. 8 and 9 are bottom views of embodiments of the acoustic assembly panel wherein the springs of the supporting structure are molded in one piece with the supporting structure;

[0040] FIG. 10 is a bottom view of the acoustic panel assembly that illustrates a second embodiment of the springs of the supporting structure;

[0041] FIGS. 11 and 12 are bottom views of the acoustic panel assembly that illustrate a third embodiment of the springs of the supporting structure;

[0042] FIG. 13 is a bottom view of a second embodiment of the acoustic panel assembly, wherein the springs are connected to a frame;

[0043] FIG. 14 is a bottom view of a variant of the acoustic panel assembly of FIG. 13, which illustrate elastic tabs that act as springs;

[0044] FIG. 15 is a sectional view taken along the sectional plane XV-XV of FIG. 14;

[0045] FIG. 16 is a bottom view of a third embodiment of the acoustic panel assembly, wherein elastic arms, which act as springs, are obtained in the frame; and

[0046] FIG. 17 is a bottom view of a fourth embodiment of the acoustic panel assembly, wherein elastic arms, which act as springs, are obtained in a peripheral portion of the acoustic panel.

DETAILED DESCRIPTION OF THE INVENTION

[0047] With reference to FIGS. 3 to 12, a first embodiment of an acoustic panel assembly according to the invention is described, which is generally indicated with reference numeral 200.

[0048] Now with reference to FIGS. 3 and 4, the acoustic panel assembly (200) comprises: [0049] an acoustic panel (4); [0050] a frame (3) that peripherally surrounds the acoustic panel (4), [0051] a support (2) integral with the frame (3), [0052] a magnetic unit (1) fixed to the support (2), and [0053] a voice coil (6) fixed to the acoustic panel (4).

[0054] The frame (3) can have a rectangular shape.

[0055] Although the acoustic panel (4) is shown with a planar, rectangular shape, it may have a non-planar, non-rectangular shape. For example, the acoustic panel (4) may be composed of a portion of a vehicle that generally has a non-planar shape, such as for example the interior of a door, the cockpit, pillars and the like.

[0056] The voice coil (106) is immersed in a magnetic field generated by the magnetic unit (1). When the voice coil (6) is crossed by electrical current, it receives a Lorentz force in the gap, which causes its movement in axial direction.

[0057] A supporting structure (8) is integral with the frame (3) and a plurality of springs (7) is connected to the supporting structure. The acoustic panel has a back surface and the springs (7) elastically support the acoustic panel (4) in different points of the back surface of the acoustic panel. The springs (7) ensure an axial movement of the acoustic panel (4), especially when the magnetic unit (1) is disposed out of the center of the acoustic panel (4).

[0058] The springs (7) can have a different thickness and consequently a different rigidity. Moreover, they can have a different shape and can be disposed in different positions to ensure the balance of the mechanical moments of the acoustic panel (4) relative to two orthogonal axes passing through the center of the acoustic panel and lying on the plane of the acoustic panel.

[0059] In the example of FIG. 4, the supporting structure (8) of the springs is a grill comprising a plurality of openings (80). The springs (7) are disposed inside at least some of said openings (80). In such a case, the support (2) of the magnetic unit (1) is integral with the supporting structure (8) of the springs. In fact, the magnetic unit (1) is disposed inside an opening (80) of the supporting structure (8) of the springs.

[0060] FIG. 4 illustrates a supporting structure (8) with 16 openings (80) disposed according to a pattern of 4 lines and 4 columns. All openings (80) have the same dimensions.

[0061] The magnetic unit is disposed in an opening (80) of the supporting structure (1), and the springs (7) are disposed in all the remaining openings in such a way to uniformly cover the entire surface of the acoustic panel (4).

[0062] By means of experimental tests, each spring (7) can be connected to a dynamometer to measure the force exerted on each spring (7) during the operation of the acoustic panel assembly (200). In such a way, the effect caused on each spring by the movement of the acoustic panel (4) can be determined. If the operation of the acoustic panel is negatively affected by some of the springs (7), the possibility of eliminating some springs or the possibility of changing the elasticity coefficient of some springs can be considered, using a spring with a different shape, a different material or a different thickness compared to the other springs, in such a way to obtain an optimal operation of the acoustic panel assembly.

[0063] FIG. 4 illustrates a supporting structure (8) fixed to the frame (3) by means of fixing means (M1), such as screws. Obviously, the fixing means (M1) of the supporting structure can consist in gluing, welding or fitting. Alternatively, the supporting structure (8) can be obtained in one piece with the frame (3).

[0064] FIG. 4 illustrates springs (7) fixed to the supporting structure (8) by means of fixing means (M2), such as screws. Obviously, the fixing means (M2) of the springs can consist in gluing, welding or fitting. Alternatively, the springs (7) can be obtained in one piece with the supporting structure (8).

[0065] For illustrative purposes, each spring (7) comprises: [0066] a central portion (70) fixed to the acoustic panel (4); and [0067] two peripheral portions (71, 72) fixed to the supporting structure (8) in diametrically opposite positions relative to the central portion (70).

[0068] The central portion (70) is connected to the peripheral portions (71, 72) by means of two arms (73, 74) with a curved shape, such as a C-shape, in such a way that the spring has an S-shape.

[0069] In the example of FIG. 4, the springs (7) are all disposed in the same direction; i.e. in each spring the straight line passing through the peripheral portions (71, 72) and the central portion (70) of the spring is always parallel to one side of the frame (3).

[0070] FIG. 5 illustrates a variant, wherein the openings (80) of the supporting structure (8) have different dimensions and the springs (7) are disposed only in some of the openings (80).

[0071] Some springs are connected to the supporting structure (80) and to the frame (3).

[0072] Some springs (7) are angularly connected only to the frame (3). In such a case, the straight line passing through the peripheral portions (71, 72) and the central portion (70) of the spring is inclined by 45 relative to the sides of the frame (3).

[0073] The springs (7) can be made of the same plastic material as the frame (3) and the supporting structure (8). Alternatively, the springs (7) can be made of a plastic material that is different from the plastic material of the frame (3) and the supporting structure (8) by means of co-molding techniques. A different thickness and a different shape of the springs can be easily obtained with the plastic injection technology in order to obtain differentiated elastic forces in the different areas of the acoustic panel (4). In any case, the manufacturing cost of the springs can be reduced with the molding or co-molding technology.

[0074] The springs (7) can be metal springs, can be applied to or co-molded with the supporting structure (8). If metal springs are used, the choice of a different thickness or shape determines the distribution of differentiated forces on the back surface of the acoustic panel.

[0075] FIGS. 6 and 7 illustrate an improvement of the spring (7) that provides for damping means (75) suitable for dampening the undesired elastic oscillations of the spring. The damping means (75) comprise two dampers (75a, 75b) with disc-like shape disposed above and under the springs (7). Each damper (75a, 75b) is made of soft elastic material, such as rubber, foam or silicone.

[0076] The first damper (75a) is disposed around the central portion (70) of the spring and is held by means of a lid comprising a shank (76) that is engaged in the central portion (70) of the spring and a flange (77) that radially protrudes from the shank (76) in order to hold the damper (75). The second damper (75b) is disposed between the acoustic panel (4) and the spring (7).

[0077] FIGS. 8 and 9 illustrate two embodiments of the acoustic panel assembly (200), wherein the frame (3), the support (2), the supporting structure (8) and the springs (7) are made in one piece by means of plastic injection molding.

[0078] FIG. 13 illustrates springs (207) according to a second embodiment. In such a case, the springs (207) consist in spiders, which are normally used to elastically support a voice coil of a loudspeaker. The spring (207) has a disc-like shape with a wavy cross-section. The spring (207) has a central portion (270) fixed to the supporting structure (8) and a peripheral annular portion (271) fixed to the acoustic panel (4). In such a case, the supporting structure (8) comprises brackets connected to the frame (3) and to the support (2) of the magnetic unit.

[0079] FIGS. 11 and 12 illustrate springs (307) according to a third embodiment. In such a case, rectilinear elastic tabs, which act as springs (307), protrude from the supporting structure (8). One end (370) of each spring (307) is fixed to the acoustic panel (4).

[0080] FIG. 13 illustrates an acoustic panel assembly (300) according to a second embodiment, wherein the springs (7) are connected to the frame (3) and to the acoustic panel (4). The support (2) is a curved bracket connected to the frame (3). In such a case, the springs (7) are only connected to the frame (3) in correspondence of the four corners of the frame (3) and no supporting structure of the springs is provided.

[0081] FIGS. 14 and 15 illustrate a variant of the acoustic panel assembly (300) of FIG. 13, wherein elastic tabs, which act as springs (107), protrude from the frame (3) towards the acoustic panel (4) and behind the acoustic panel (4). The spring (107) has a wavy shape and a planar ending section (170) fixed to the acoustic panel (4) by means of fixing means (M3), such as gluing or welding. The spring (107) has a length (L1) and a width (W) that are chosen according to the areas of the acoustic panel (4) to be elastically supported.

[0082] FIG. 16 illustrates an acoustic panel assembly (400) according to a third embodiment. In such a case, elastic arms, which act as springs (407), elastically connect a peripheral portion (33) of the frame to a central portion (30) of the frame fixed to the acoustic panel (4). Said elastic arms that act as springs (407) are obtained by means of through notches (31, 32) in the frame. Each elastic arm that acts as spring (407) has an internal portion (470) connected to the central portion (30) of the frame and an external portion (471) connected to the peripheral portion (33) of the frame.

[0083] The elastic arms that act as springs (407) can be integrally obtained with the frame (3), for example, by means of injection molding or co-molding in the same material as the frame (3) or in a different material.

[0084] FIG. 17 illustrates an acoustic panel assembly (500) according to a fourth embodiment.

[0085] In such a case, elastic arms that act as springs (507) elastically connect a central portion (40) of the acoustic panel to a peripheral portion (4e) of the acoustic panel (4) fixed to the frame (3). Said elastic arms that act as springs (507) are obtained by means of through notches (41, 42) in the acoustic panel. Each elastic arm that acts as spring (407) has an internal portion (570) connected to the central portion (40) of the acoustic panel, and an external portion (571) connected to the peripheral portion (43) of the acoustic panel.

[0086] Numerous equivalent variations and modifications can be made to the present embodiments of the invention, which are within the reach of an expert of the field and fall in any case within the scope of the invention as disclosed by the appended claims.