GB2344016A

GB2344016A - An ABR loudspeaker using body panels to form a closed air box within a motor vehicle

Info

Publication number: GB2344016A
Application number: GB9924919A
Authority: GB
Inventors: Tiziano Nili
Original assignee: Ask Industries SpA
Current assignee: Ask Industries SpA
Priority date: 1998-11-23
Filing date: 1999-10-21
Publication date: 2000-05-24
Anticipated expiration: 2019-10-21
Also published as: PL195757B1; ES2160075B1; TR199902460A2; GB9924919D0; ES2160075A1; FR2786357B1; DE19956254A1; PL336730A1; ITRE980117A1; DE19956254C2; BR9907546A; AR021856A1; FR2786357A1; IT1305338B1; GB2344016B

Abstract

Empty volumes 1 usually present in glove compartments, doors and the like of motor vehicles, are used to constitute closed air volume boxes for "active" loudspeakers 6 combined with passive elements, ie a drone cone. The dimensions of the closed air volume being the same as are obtained by adopting the same ABR system in pre-arranged boxes. This arrangement increases the efficiency of the loudspeaker at the low frequencies.

Description

2344016 PASSIVE ELEMENTS IN CLOSED VOLUME FOR LOUDSPEAKERS The present

invention relates to passive elements for loudspeakers, that can be inserted and housed in closed volumes obtained in the empty spaces present in various parts of motor-cars, for instance in the finishing parts of the inside of panels, glove compartments and the like, wherein said closed volumes create the conditions necessary for the passive elements, on damping elements, associated to loudspeakers that exploit the same air volume.

As is known in the technology of sound transmission and in particular in the specific one concerning loudspeakers, by the term "passive" there is intended to indicate an element whose working is not generated by own "motors", having no coils, magnets or other elements suitable to serve for its operation as a conventional loudspeaker, but is only constituted by a membrane whose mass is so calibrated as to move in phase with a primary pilot or "active" loudspeaker that causes its excitation. It is also known that a passive element placed on a truing element, hinge or damping element, that works in co-operation with a loudspeaker exploiting the same air volume available, the dimensions being equal, produces, in respect of the latter, an increase in efficiency at low frequencies. This system increases the vibrating surface of the active element, as it is caused to move by the compressions and rarefactions generated by the movement of the membrane of the loudspeaker. The present combination of the so-called "active-passive" elements, is realized by creating special containers or boxes whose air volume is determined according to the characteristics of the active loudspeaker; in the same way, also the value of the mass of the corresponding passive membrane, which is so constituted as to move in phase with the loudspeaker, is calibrated and calculated according to said characteristics.

The internal air of the containment boxes is not connected with external air.

The realization of the above described system, while having proved to be valid with respect to the increase in efficiency of loudspeakers at low frequencies, the dimensions being the same, has some drawbacks with regard to the possible practical applications, especially those for radio and the like for motor vehicles in general, because of their overall size.

This invention seeks to solve the above drawbacks. According to the invention there is provided a passive element operating in combination with an active loudspeaker to produce an increase of the loudspeaker efficiency, particularly at low frequencies, and housed in an empty space having an air closed volume determined according to the characteristics of the loudspeaker, characterized in that the passive element and the active loudspeaker are housed in one of the empty spaces of a motor vehicle and in that the required air closed volume is obtained by at least partially exploiting said empty space of the motor vehicle. Thus the problem is solved by means of passive elements for loudspeakers inserted in closed volume that can be housed without restraints in various parts of motor vehicles, by means of which the following results are achieved: the loudspeakers and the related calibrated passive elements are housed in already existing spaces or spaces suitably configured during the forming of the vehicle body, in the inside of panels, glove compartments or the like. In this way, the same spaces take on the function of the conventional boxes having a pre-determined and circumscribed air volume, and the active loudspeakers, with the related passive membranes, are directly housed in their inside.

One advantage achieved according to the present invention lies essentially in that the spaces and empty volumes existing in the inside of the vehicle are directly 3- exploited to house the system, without needing specific supplementary boxes; the lack of boxes allows a reduction in weights, a reduction in the number of the components, a reduction in costs and an easier assembly; the application allows the desired increase in the efficiency of the acoustic system to be obtained at the low frequencies.

The invention will now be described in greater detail, by way of example, with reference to the drawings, in which:- Figure I is a schematic view of two combinations of active loudspeakers with the related passive membranes, inserted in empty spaces of different shapes, present in or obtained in vehicles; Figure 2 is the magnified cross-section of one embodiment of a passive membrane.

With reference to the drawings, the situation required to achieve the purposes and advantages mentioned is obtained in the inside of any motor vehicle, such as a motor car, exploiting the necessary closed air volume of the partial or total configurations of the finishing spaces which are usually present in the inside of door panels, glove compartments or the like (2). As an alternative and depending on the expectation of the manufacture of a series of motor vehicles the reduced air volume closed empty spaces (1) necessary to achieve the same purposes mentioned above, may be realized, according to the configurations and dimensions desired, directly with the molding and assembly operations for the production of vehicle bodies and/or body parts of the motor vehicles. In any case, the openings in corresponding loudspeakers (6) and passive membranes (7) are applied and created on the internal supporting structures (3) of said spaces. Openings (4) are enclosed and their surfaces are protected, towards the inside of the vehicles, with porous coverings such as the remaining covering moquettes and/or the like (5).

Loudspeakers (6) are co-axially attached with respect to corresponding openings (4) by conventional fastening means. The passive membranes (7) instead, are connected to the supporting structures (3) through, for instance, peripheral crowns (8) on which central masses (9) engage by means of damping elastic elements or intermediate truing elements (10). The central masses, or passive radiators (9), are obtainable also from punched surfaces derived from the same supporting structure and may be possibly coupled to calibration or mechanical balance masses (11) to obtain the exact calculated weight, according to the primary loudspeakers (6) that pilots it.

In substance, the invention lies in that the situation obtainable by the whole constituted by a passive element (7), placed on a damping element (10), which operates in co-operation with a loudspeaker (6) exploiting the same closed air volume (1), the same as that constituted by a conventional box (12) to generate an increase in efficiency of the loudspeaker at the low frequencies and, the dimensions being the same, this is obtained in the inside of a motor vehicle wherein the necessary closed air volume is created by such a configuration as to partly or totally exploit the existing empty spaces (2) or spaces realized during the formation of the car bodies, situated between the finishing of the inside of said panels, said glove compartments and/or other similar or suitable places of the motor vehicle.

Obviously, depending on the configurations and/or the various requirements of applicability in the closed air volume empty spaces (1) available, either existing or specially obtained, the passive vibrating elements (7) may also be realised with different structures, provided their mass is so calculated and calibrated as to achieve the primary requirement of their moving being in phase with the associated active elements or loudspeakers (6).

Claims

1. A passive element operating in combination with an active loudspeaker to produce an increase of the loudspeaker efficiency, particularly at low frequencies, and housed in an empty space having an air closed volume determined according to the characteristics of the loudspeaker, characterized in that the passive element and the active loudspeaker are housed in one of the empty spaces of a motor vehicle and in that the required air closed volume is obtained by at least partially exploiting said empty space of the motor vehicle.

2. The passive element according to claim 1, wherein the empty space containing the required air closed volume is that already existing in the inside of the motor vehicle.

3. The passive element according to claim 1, wherein the empty space containing the required air closed volume is realized during the molding of the motor vehicle body.

4. The passive element according to claim 1, wherein the empty space containing the required air closed volume is realized during the molding of parts of the motor vehicle body.

5. The passive element according to claim 4, wherein the empty space containing the required air closed volume is realized during the molding of door panels of the motor vehicle.

6. The passive element according to claim 4, wherein the empty space containing the required air closed volume is realized during the molding of glove compartments.

7. The passive element according to claim 1, wherein the empty space containing the required air closed volume is realized during the assembly of the motor vehicle body.

8. The passive element according to any one of the preceding claims, wherein the empty space containing the required air closed volume is arranged in the inside of the panels.

9. The passive element according to any one of the preceding claims from 1 to 5, wherein the empty space containing the required air closed volume is arranged in the inside of glove compartments.

10. The passive element according to any one of the preceding claims, wherein the passive element is connected to a supporting structure by peripheral crowns.

11. The passive element according to claim 10, wherein the peripheral crowns engage central masses or passive radiators by means of damping elastic elements or intermediate truing elements.

12. The passive element according to claim 11, wherein the central masses or passive radiators are obtained from punched surfaces of the supporting structure, optionally, coupled to calibration or mechanical match added masses.

13. A passive element operating in combination with an active loudspeaker to produce an increase of the loudspeaker efficiency, particularly at low frequencies, and housed in an empty space having an air closed volume determined according to the characteristics of the loudspeaker and substantially as described herein with reference to the drawings.