FR3128087A1 - DEVICE FOR FIXING A LOUDSPEAKER IN AN AERIAL OF A AUDIO HELMET AND ASSOCIATED FIXING METHOD - Google Patents

Abstract

The invention relates to the technical field of earpiece audio headsets comprising at least one loudspeaker, also relates to the method of mounting the loudspeaker inside each earpiece. The invention finds multiple applications, in particular for passive or active noise reduction headphones.

Description

DEVICE FOR FIXING A LOUDSPEAKER IN AN AERIAL OF A AUDIO HELMET AND ASSOCIATED FIXING METHOD

The invention relates to the technical field of audio headsets comprising at least one loudspeaker. The invention also relates to the method of mounting the loudspeaker inside each headset.

The invention finds multiple applications, in particular for passive or active noise reduction headphones.

STATE OF THE ART

Audio headsets have experienced significant growth in recent years, in particular with the development of a large number of electronic functions integrated into audio headsets. For example, audio headsets are integrating more and more electronic functions, such as the suppression of external noise to improve user comfort and the quality of the sound content transmitted to the user.

In addition, other electronic functions can also be integrated into these audio headsets, such as a function allowing the active noise reduction system to be switched off by an action by the user on an earpiece or even automatic transmission of telephone communications. received by the user on his mobile phone.

Another electronic function consists of recognizing when the user removes his headphones from his ears and ordering the shutdown of the electronic functions of the latter in order to save battery power.

Although these new functionalities have led to a growing development of the audio headset sector, the invention relates more generally to all types of audio headsets and also to passive audio headsets, that is to say audio headsets incorporating very few electronics or even no electronic control of the transmitted sound.

The invention relates more specifically to headsets comprising circum-auricular or supra-auricular earpieces, unlike intra-auricular earpieces.

These earpieces include a pad positioned on the ear or surrounding the ear of the user, and making it possible to create a frontal listening cavity soundproofed from the external environment. This frontal cavity is formed by a frontal wall supporting the loudspeaker to the edge of which the cushion is fixed. Behind this front wall, the earpieces generally incorporate a shell and possibly electronic means for controlling the loudspeaker.

Conventionally, the loudspeaker is fixed in the headset by gluing its bowl to the front wall. Indeed, a loudspeaker is conventionally sold with a circular basket fixed to the moving assembly. In some embodiments, the outer edge of the moving assembly is connected to the basket by means of a suspension. The internal edge of the suspension is, for its part, fixed to the membrane of the moving assembly, the movements of which ensure the generation of acoustic waves. To obtain the desired displacements of the mobile assembly, a motor is fixed to the basket and it generates a constant magnetic field. A variable voltage is applied in the coil of the mobile assembly, which makes it possible to move the mobile assembly with more or less amplitude.

The gluing of the loudspeaker basket on the front wall nevertheless imposes several technical problems.

First, to ensure effective bonding of the salad bowl to the front wall, it is often necessary to use a chemical glue presenting health risks to the personnel securing the salad bowl to the front wall.

In addition, this chemical glue is generally harmful to the environment.

In addition, gluing the bowl to the front wall greatly complicates the repairability of the headset because, to disassemble the loudspeaker from the front wall, it is necessary to heat the glue until it evaporates. This operation must be carried out under a suction system in order to limit the risk of poisoning. In addition, in some cases it is not even possible to remove this glue so that the helmet cannot be repaired.

Furthermore, during the operations of gluing the salad bowl to the front wall, it is necessary to ensure the limitation of acoustic leaks between the front cavity and the rear cavity of the headset, the rear cavity being defined between the shell and the front wall. Leaks between these two cavities can occur if part of the bowl is not perfectly stuck to the front wall. To guarantee limited leaks, when the loudspeaker is glued to the front wall, the operator must wait for the complete drying of the glue and must then check that the leaks are very limited, preferably completely zero, at the level of the zone of speaker bonding. If it detects leaks greater than a threshold value in this zone, it can then redeposit a layer of adhesive to fill these leaks. This operation is therefore very time consuming.

In an approach to protect the environment and the personnel acting during the assembly and disassembly of the helmets, solutions are sought for fixing the basket on the front wall making it possible to respond to the drawbacks of the state of the art.

INVENTION

The invention proposes to respond to this technical problem by using a loudspeaker basket 10 removably fixed to the front wall 20 through the reversible cooperation of mechanical means.

To do this, as illustrated in the , the loudspeaker basket 10 has a substantially circular shape. The central ring 11 of the salad bowl 10 comprises an internal wall 12 intended to receive the moving assembly and an external wall 13 comprising said mechanical means. The loudspeaker, which includes the mobile assembly, the motor and the salad bowl 10 , is intended to fit into a central opening 21 of the front plate 20 , illustrated in the .

In particular, the outer wall 13 of the salad bowl 10 comprises a rigid insertion tongue 14 extending radially towards the outside of the salad bowl 10 . The insertion tab 14 can have a semi-circular shape or even a rectangular shape. The insertion tab 14 is intended to cooperate with an abutment housing 22 of the front wall 20 .

The abutment housing 22 is surmounted by a protrusion 23 extending radially towards the inside of the front wall 20 . Thus, when the salad bowl 10 is inserted into the central opening 21 of the front wall 20 , the protrusion 23 blocks any vertical translational movement of the tab, thus preventing the salad bowl from being extracted from the central opening 21 .

In addition, to limit any acoustic leaks that may appear with this type of mechanical assembly, the protrusion 23 has a through hole to accommodate a leak-proof screw 43 that presses against the insertion tab 14 in order to hold the salad bowl 10 pressed against the front wall 20 at the level of the insertion tongue 14 and thus to reduce the acoustic leaks in this zone. The salad bowl 10 also comprises at least one protrusion 15 intended to cooperate with a deformable lug 25 of the front wall 20 .

Preferably, the deformable lug 25 extends perpendicular to the front wall 20 over a length of between 0.5 and 1.5 cm. The deformable lug 25 comprises a body 27 surmounted by a head 26 having a beveled face making it possible to constrain the head 26 to rest on the protuberance 15 . Thus, when the salad bowl 10 is inserted into the central opening 21 of the front wall 20 , the deformable lug 25 retains the salad bowl in the central opening 21 .

In a preferred embodiment, the deformable lugs 25 and the corresponding protuberances 15 are two in number and are distributed symmetrically on either side of the abutment housing 22 .

In addition, to limit any acoustic leaks that may appear with this type of mechanical assembly, the salad bowl 10 also comprises at least two lugs 16 intended to come opposite two bases 24 for receiving the lugs 16 . The ears 16 have a square shape, the upper portion of which extends radially towards the outside of the salad bowl 10 . Each ear 16 has a through hole cooperating with a tapped hole of the bases 24 , for example a blind hole. The bases 24 are for example of cylindrical shape and extend perpendicularly with the front wall 20 . Alternatively, the salad bowl 10 may have only one ear 16 , diametrically opposite the insertion tongue 14 .

A leak-proof screw 34 can thus pass through the hole of the lug 16 and come to be plugged into the blind hole of the base 24 in order to maintain the bowl 10 pressed against the front wall 20 at the level of the lug 16 and thus to reduce leaks. acoustics in this area.

As shown on the , a cover 30 can be attached to the assembly formed by the combination of the bowl 10 and the front wall 20 . The cover 30 has reception sites 31 for fixing screws 33 of the cover 30 on the front wall 20 . The cover 30 may also include additional openings 32 allowing the insertion of the anti-leak screws 34 in the cavity formed between the cover 30 and the front wall 20 so as not to have to unscrew the cover 30 in order to fix the anti-leak screws 34 on the ears 16 .

As illustrated in Figures 1 and 4, the salad bowl 10 also includes a connector 17 including two pads 19 for connecting the loudspeaker to the electronic card. Connector 17 also includes a female plug 18 .

This connector 17 makes it possible to connect the loudspeaker to the electronic card of the helmet in two ways. This electronic card is for example positioned in the cavity formed between the cover 30 and the front wall 20 .

The first way consists in connecting a layer of wire 41 , for example of the FPC type, connected to the electronic card of the helmet in the female plug 18 . The electronic card can be screwed into the outer shell of the helmet, which is located behind the cover 30 . The sheet of wires 41 then passes through an opening made in the cover 30 to join the electronic card.

The second way consists in bringing a male connector 35 comprising two pins 36 into contact with the two pads 19 of the connector 17 . The male connector 35 is preferably located under the cover 30 . Closing the cover causing pins 36 to come into contact with pads 19 . Alternatively, if the helmet is passive, it does not include a cover 30 . It is directly the outer shell of the helmet which allows the pins 36 to be brought into contact with the pads 19 .

Alternatively, the electronic card can be positioned anywhere in the helmet.

As shown on the , the invention also relates to a method of mounting 100 of the loudspeaker inside each headset and of verifying the compliance of the attachment with respect to acoustic leaks.

More specifically, as shown in the , the first step 101 of the method consists in positioning the insertion tab 14 in the abutment housing 22 . To do this, the abutment housing 22 preferably has a semi-circular shape extending radially outwards relative to the center of the loudspeaker when the latter is fixed to the front wall 20 . The insertion tab 14 also preferably has a shape adapted to the semi-circular shape of the abutment housing 22 . When the insertion tab 14 is inserted into the abutment housing 22 , the bowl 10 can be pressed against the front wall 20 so as to cause the at least one deformable lug 25 of the front wall 20 to cooperate with the at least a protuberance 15 of the salad bowl 10 , in a step 102 .

Preferably, the salad bowl 10 can comprise two protrusions 15 capable of cooperating with two deformable lugs 25 .

The deformable lugs 25 are preferably positioned with the insertion tongue 14 so as to substantially form an equilateral triangle inscribed in the ring of the salad bowl 10 .

The loudspeaker motor can be attached to the salad bowl 10, for example by means of the housings 44 . The motor is fixed by the rotation of fins in the housings 44 .

In step 103 , a cover 30 can then be attached to the front wall 20 . For example, in a step 104 , the partial fixing of the cover 30 can be ensured by the screwing of two first fixing screws 33 . These first fixing screws 33 are inserted into reception sites 31 provided for this purpose on the cover 30 . These reception sites 31 have a through opening and cooperate with studs 29 of the front plate 20 . The studs 29 further comprise an opening making it possible to screw in the first fixing screws 33 . Thus, the first fixing screws 33 pass through the reception sites 31 before plugging into the studs 29 , thus holding the cover to the front plate 20 . The reception sites 31 of the first fixing screws 33 are preferably furthest from the openings 32 in order to homogenize the distribution of the screws. In this same step 104 , two anti-leakage screws 34 are fixed through the cover 30 by crossing the openings 32 . These leak-proof screws 34 penetrate the openings of the ears 16 to be screwed into the bases 24 and limit acoustic leaks.

After fixing the cover 30 , the leaks between the front cavity and the rear cavity can be measured, in a step 105 , so as to determine whether the anti-leak screws 34 are sufficient to guarantee the limitation of acoustic leaks according to the desired performance. To do this, a microphone can be placed in the front cavity and in the rear cavity while the loudspeaker is used to generate sounds over an expected frequency range.

If a new need for limiting leaks is observed, it is possible, in a step 106 , to add two other fixing screws 37 to the cover 30 . To do this, the two other fixing screws 37 are also inserted into reception sites 31 provided for this purpose on the cover 30 . These reception sites 31 also cooperate with studs 29 of the front plate 20 .

In a step 107 , the leaks between the front cavity and the rear cavity are again measured. If a new need for limiting leaks is observed, it is possible, in a step 108 , to improve the fixing of the bowl 10 on the front wall 20 by dismantling the fixing screws 33 , 37 and the anti-leakage screws 34 of the cover 30 and inserting a new anti-leakage screw 43 into the protrusion 23 to press against the insertion tab 14 .

Finally, step 109 aims to reassemble the cover 30 with the four fixing screws 33, 37 and the two anti-leak screws 34 and to measure the remaining leaks in order to ascertain the compliance of the assembly of the salad bowl 10 with respect to the desired performance.

Claims (1)

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