WO2015128554A1 - Plastic automobile glazing with acoustic properties - Google Patents

Plastic automobile glazing with acoustic properties Download PDF

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Publication number
WO2015128554A1
WO2015128554A1 PCT/FR2015/050154 FR2015050154W WO2015128554A1 WO 2015128554 A1 WO2015128554 A1 WO 2015128554A1 FR 2015050154 W FR2015050154 W FR 2015050154W WO 2015128554 A1 WO2015128554 A1 WO 2015128554A1
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WO
WIPO (PCT)
Prior art keywords
glazing
acoustic
plastic
thickness
periphery
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Application number
PCT/FR2015/050154
Other languages
French (fr)
Inventor
François van Herpe
Patrick Chanudet
Original Assignee
Peugeot Citroen Automobiles Sa
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Peugeot Citroen Automobiles Sa filed Critical Peugeot Citroen Automobiles Sa
Priority to CN201580011193.3A priority Critical patent/CN106061778B/en
Priority to EP15704353.0A priority patent/EP3110640A1/en
Publication of WO2015128554A1 publication Critical patent/WO2015128554A1/en

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60J—WINDOWS, WINDSCREENS, NON-FIXED ROOFS, DOORS, OR SIMILAR DEVICES FOR VEHICLES; REMOVABLE EXTERNAL PROTECTIVE COVERINGS SPECIALLY ADAPTED FOR VEHICLES
    • B60J1/00—Windows; Windscreens; Accessories therefor
    • B60J1/008—Windows; Windscreens; Accessories therefor of special shape, e.g. beveled edges, holes for attachment, bent windows, peculiar curvatures such as when being integrally formed with roof, door, etc.

Definitions

  • FIG. 1 illustrates an embodiment of a motor vehicle 2 comprising numerous glazings 4.
  • a large glazed area of a vehicle is a growing trend of embodiment, this being mainly related to the visual comfort that such an embodiment can provide to the car. user.
  • Another growing trend is the production of lighter vehicles, which are interesting from an economic point of view for the user, because it contributes to lower fuel consumption.
  • the windows of a motor vehicle are a significant part of its mass.
  • the ratio between the mass of a glass automotive glass and that of a plastic automotive glazing is of a factor substantially equal to two, of equivalent thickness.
  • the acoustic insulation of a glazing as an acoustic barrier has different characteristics on the different audible frequency ranges.
  • plastic glazing because of its lower density, offers poorer acoustic performance at low audible frequencies; At equivalent thickness, and also by its lower density, the plastic glazing has a drop in acoustic performance around 10kHz, where for glass glazing the fall occurs around 4kHz. It is therefore desirable that the realization of a motor vehicle with lightened glazing can satisfy an acceptable sound insulation of the vehicle, the lightening thereof should not be at the expense of the associated manufacturing cost.
  • the invention aims to facilitate the realization of a motor vehicle with plastic glazings so as to reduce the total mass of the vehicle and in an economically viable perspective. More particularly, the invention aims to improve the acoustic comfort of a vehicle with such glazing, more particularly to reduce the acoustic transmission over the frequency range 5kHz to 10kHz.
  • the invention relates to a plastic glazing intended to be mounted in abutment on its periphery, in particular on a motor vehicle body, remarkable in that the glazing comprises at least one portion of variable thickness, said portion being intended to modify the speed of propagation of vibratory waves in the glazing so as to reduce the acoustic transmission of said glazing over the frequency range 5 kHz to 10 kHz.
  • the glazing is made of material, preferably polycarbonate or preferably polymethyl methacrylate.
  • the portion has a thickness varying from 15% to 40% of the average thickness of the glazing.
  • the portion extends essentially to the periphery of the glazing, said portion being of variable thickness in a peripheral direction, said periphery having a width of between 1% and 15% of the largest dimension. glazing.
  • the portion is of variable thickness, moreover, in a direction orthogonal to the peripheral direction.
  • the portion extends in the central part of the glazing or on the entire surface of the glazing.
  • the glazing is of an average thickness of between 4 mm and 8 mm, the acoustic attenuation measurement of the glazing being improved from 0 to 5 dB over the frequency range corresponding to the acoustic coincidence zone of the glazing.
  • the invention also relates to a process for shaping a plastic glazing by injection molding, remarkable in that the glazing is in accordance with the invention.
  • the invention also relates to a tool, remarkable in that it is configured to implement the method according to the invention, said tool comprising a mold having a convex shape so as to shape the inner face of the glazing said face being intended to be inwardly of a motor vehicle.
  • the invention also relates to a motor vehicle, remarkable in that it comprises at least one plastic glazing according to the invention, said glazing being mounted on the vehicle body preferably by gluing.
  • the measurements of the invention are interesting in that they make it possible to reduce the noise in the vehicle over the critical range of high frequencies from 5 kHz to 10 kHz. Indeed, the thickness variation in the glazing changes the wavelength, and speed, of the bending wave in the glazing, so as to reduce the loss of transmission losses of the sound waves.
  • the acoustic barrier of the improved plastic glazing facilitates the realization of a lighter motor vehicle, while reducing the transmission of acoustic waves from the outside of the vehicle compared to known plastic windows.
  • FIG. 2 is a block diagram illustrating the loss of sound transmission through a glazing unit
  • FIG. 3 is a principle graph illustrating the drop in the transmission loss through the glazing unit of FIG. 2;
  • FIG. 4 is a radial sectional view of a glazing unit of FIG. 1 and an enlarged view of two portions of the glazing unit;
  • FIG. 5 is a graph illustrating the reduction of the loss of transmission losses of a glazing unit according to a preferred embodiment of the invention.
  • FIG. 6 is a front view of a glazing of the vehicle of Figure 1 according to a preferred embodiment
  • FIG. 7 is a sectional view of a periphery of the glazing of Figure 6;
  • FIG. 8 is a radial sectional view of the window of Figure 6.
  • Figure 1 is a view of a vehicle 2 comprising at least one outer glazing 4 according to the invention.
  • the glazing 4 is supported on the body and fixed by gluing on a body rebate.
  • the glazing 4 may be a quarter panel glazing or roof or rear window.
  • the glazing 4 is of organic main material 6, it is favorably plastic so as to lighten the vehicle. It is for example polycarbonate or polymethylmethacrylate.
  • FIGS. 2 and 3 illustrate known principles of the acoustic barrier as well as the fall in the acoustic performance of a glazing over a critical frequency range, phenomena that must be understood in order to understand their effect on the sound insulation of a vehicle.
  • FIG. 2 shows the glazing 4 of the vehicle 2, glazing above which is represented a first arrow illustrating an external sound power and below which is shown a second arrow, of smaller size, illustrating a sound power transmitted inside of the vehicle 2.
  • the difference in size arrows schematizes transmission losses (in dB) "transmission loss" of sound power through a glazing, specifically a solid and airtight glazing. These losses are embodied by a noise reduction between the outside and the inside, the glazing becoming commonly called an acoustic barrier.
  • dB transmission loss
  • Figure 3 illustrates the phenomenon of falling transmission losses of a glazing, in other words a greater passage of noise through the glazing, this phenomenon occurring according to the glazing over a certain critical frequency range f.
  • the image on the critical frequency zone C (in Hz) generally illustrates the suddenness of the phenomenon.
  • the low point of the loss loss corresponds physically to a spatial and frequency coincidence of the bending waves (A f i ex ) in the glazing and acoustic waves (A air ) in the air enveloping the glazing.
  • the plastic glazing in the context of the invention, is configured to provide a reduction in the noise transmission in the acoustic coincidence zone, more precisely in this frequency range of 5kHz to 10kHz more audible .
  • Figure 4 is a radial sectional view of the glazing unit 4 according to the invention.
  • the image also includes enlargements of two regions of the glazing.
  • the glazing 4 comprises at least one portion 8 of variable thickness T.
  • AD (shown in the image) corresponds to the variation of the variable thickness T in the portion 8 of the glazing 4.
  • the quality of the acoustic barrier of the glazing varies, as seen above, according to the speed V of propagation of the vibratory wave (or bending) in the glazing, itself dependent on the frequency of the sound wave as well as the flexural wavelength in the glazing. However, the non-uniformity of the thickness of the glazing directly influences this speed V.
  • the bending wave (A f i ex ) in the glazing 4 is proportional to the square root of the thickness T of the glazing 4.
  • the propagation velocity V in the portion 8 is also not.
  • the portion 8 not being limited in the glazing 4, the propagation velocity V may not be uniform over the entire surface of the glazing 4.
  • the portion 8 may extend in the central portion 12 of the glazing 4, it may also extend over the entire surface 14 of the glazing 4 or on its periphery 20.
  • AD is 15% to 40% of the average thickness 16 of the glazing 4.
  • the sound attenuation measurement of the glazing can be improved up to 5 dB over the frequency range 5 kHz to 10 kHz.
  • the glazing 4 is preferably made by a molding process by injection molding.
  • a tool is configured to implement the method, it comprises a mold having a convex shape so as to shape the inner face 18 of the glazing 4, said face being intended to be inwardly of a motor vehicle.
  • FIG. 5 illustrates by a graph the reduction of the drop in transmission losses of a glazing unit 4 according to the invention. More precisely, a first graph (in dashed line) represents the transmission losses of a conventional plastic glazing, the second graph (in solid lines) representing the transmission losses of a plastic glazing unit 4 according to the invention.
  • the thickness of the reference glazing is 6mm, that according to the invention is of a thickness ranging from 4mm to 8mm.
  • the second graph on the contrary remains on a sound barrier plateau equivalent to the acoustic reduction achieved for frequencies between 4kHz and 5Hz.
  • Figure 6 is a front view of the glazing 4 according to a preferred embodiment.
  • the portion 8 of variable thickness T extends to the periphery 20 of the glazing 4. It extends in this case over a portion of the periphery 20. Alternatively, the portion 8 may extend over the entire periphery 20.
  • the portion 8 at the periphery 20 may be of a width 22 between 1% and 15% of the largest dimension 24 of the glazing 4.
  • the portion 8 is of variable thickness T, in addition, in a direction orthogonal to the peripheral direction. The portion 8 then extends into the central portion 12 of the glazing 4. In a preferred embodiment the portion 8 may also extend over the entire surface 14 of the glazing 4.
  • Figure 7 is a sectional view along the periphery of the glazing 4 according to a preferred embodiment.
  • the variation in thickness AD1 of the portion 8 of variable thickness T extends in a peripheral direction.
  • Figure 8 is a radial sectional view to the glazing 4 according to a preferred embodiment.
  • the variation in thickness AD2 of the portion 8 of variable thickness T extends in a direction orthogonal to the peripheral direction.

Abstract

The invention relates to plastic glazing (4) intended to be mounted resting on its periphery (20), notably on automotive vehicle bodywork, said glazing (4) comprising at least one portion (8) of variable thickness T, said portion (8) being intended to alter the speed at which vibration waves propagate through the glazing (4) so as to reduce the sound transmission of said glazing (4). The invention also relates to a method for shaping such glazing (4) by injection moulding. The invention also relates to tooling for such a method, said tooling comprising a mould of a convex shape so as to shape the internal face (18) of the glazing, said face (18) being intended to face toward the inside of a motor vehicle. The invention also relates to a vehicle comprising such glazing.

Description

VITRAGE AUTOMOBILE EN PLASTIQUE A PROPRIETES ACOUSTIQUES  AUTOMOBILE PLASTIC GLAZING WITH ACOUSTIC PROPERTIES
L'invention a trait au domaine des véhicules automobiles pourvus de vitrages. Plus particulièrement l'invention a trait à la réalisation de véhicules automobiles pourvus de vitrages en plastique. La figure 1 illustre une réalisation de véhicule automobile 2 comprenant de nombreux vitrages 4. Une grande surface vitrée d'un véhicule est une tendance croissante de réalisation, celle-ci étant majoritairement liée au confort visuel qu'une telle réalisation peut procurer à l'utilisateur. Une autre tendance croissante est la réalisation de véhicules allégés, ceux-ci étant intéressants d'un point de vue économique pour l'utilisateur, car il contribue à une plus faible consommation de combustible. Or, les vitrages d'un véhicule automobile sont une partie non négligeable de sa masse. A titre d'exemple et d'ordre de grandeur, le rapport entre la masse d'un vitrage automobile en verre et celle d'un vitrage automobile en plastique est d'un facteur sensiblement égal à deux, à épaisseur équivalente. Or, un vitrage en verre est toujours jusqu'à aujourd'hui un mode majoritaire de réalisation notamment grâce à son coût relativement économique pour le constructeur du véhicule. Il est donc intéressant pour un constructeur automobile de réaliser un véhicule à vitrages plus légers, si le coût de fabrication reste toutefois contenu, la différentiation sur la masse du véhicule pouvant devenir un atout commercial. La réalisation d'un véhicule à vitrage plus léger ne peut se faire en revanche au détriment du confort au niveau des bruits pour l'utilisateur. Il est en effet connu que la qualité de l'isolation acoustique d'un véhicule est notamment liée au type de vitrages utilisés. The invention relates to the field of motor vehicles with glazing. More particularly the invention relates to the production of motor vehicles with plastic glazing. FIG. 1 illustrates an embodiment of a motor vehicle 2 comprising numerous glazings 4. A large glazed area of a vehicle is a growing trend of embodiment, this being mainly related to the visual comfort that such an embodiment can provide to the car. user. Another growing trend is the production of lighter vehicles, which are interesting from an economic point of view for the user, because it contributes to lower fuel consumption. However, the windows of a motor vehicle are a significant part of its mass. By way of example and order of magnitude, the ratio between the mass of a glass automotive glass and that of a plastic automotive glazing is of a factor substantially equal to two, of equivalent thickness. However, a glass glazing is still until now a majority mode of realization especially thanks to its relatively economic cost for the vehicle manufacturer. It is therefore interesting for a car manufacturer to make a vehicle with lighter glazing, if the manufacturing cost remains contained, the differentiation on the mass of the vehicle can become a commercial asset. The realization of a lighter glazed vehicle can not be done however at the expense of comfort in terms of noise for the user. It is indeed known that the quality of the acoustic insulation of a vehicle is particularly related to the type of glazing used.
L'isolation acoustique d'un vitrage en tant que barrière acoustique a des caractéristiques différentes sur les différentes plages de fréquences audibles. En termes comparatifs, le vitrage en plastique, de par sa plus faible densité, offre de moins bonnes performances acoustiques aux basses fréquences audibles ; A épaisseur équivalente, et aussi de par sa plus faible densité, le vitrage en plastique présente une chute de performances acoustiques autour des 10kHz, là où pour le vitrage en verre la chute se produit autour de 4kHz. Il est donc souhaitable que la réalisation d'un véhicule automobile avec des vitrages allégés puisse satisfaire à une isolation sonore acceptable du véhicule, l'allégement de celui-ci ne devant pas se faire au dépend du coût de fabrication associé. The acoustic insulation of a glazing as an acoustic barrier has different characteristics on the different audible frequency ranges. In comparative terms, plastic glazing, because of its lower density, offers poorer acoustic performance at low audible frequencies; At equivalent thickness, and also by its lower density, the plastic glazing has a drop in acoustic performance around 10kHz, where for glass glazing the fall occurs around 4kHz. It is therefore desirable that the realization of a motor vehicle with lightened glazing can satisfy an acceptable sound insulation of the vehicle, the lightening thereof should not be at the expense of the associated manufacturing cost.
De manière à réduire le bruit transmis, il est connu de chercher à réduire l'amplitude des ondes de flexion dans le vitrage par l'usage de verres laminés (ou feuilletés) enrobant des films intercalaires ayant des propriétés viscoélastiques, par exemple du polyvinyle de butyral. Cette modification est intéressante en ce qu'elle amortit la chute des pertes de transmission par dissipation de l'énergie mécanique (vibration) dans les films de plus faible raideur. Elle est toutefois difficilement applicable pour des vitrages organiques, notamment en plastique, en raison du surcoût associé. In order to reduce the transmitted noise, it is known to seek to reduce the amplitude of the bending waves in the glazing by the use of laminated glasses (or laminates) coating interlayer films having viscoelastic properties, for example polyvinyl butyral. This modification is interesting in that it damps the loss of transmission losses by dissipation of mechanical energy (vibration) in films of lower stiffness. However, it is difficult to apply for organic glazing, especially plastic, because of the additional cost associated.
L'invention a pour objectif de faciliter la réalisation d'un véhicule automobile avec des vitrages en plastique de manière à réduire la masse totale du véhicule et ce dans une optique économiquement viable. Plus particulièrement l'invention a pour objectif d'améliorer le confort acoustique d'un véhicule muni de tels vitrages, plus particulièrement encore de diminuer la transmission acoustique sur la plage de fréquences de 5kHz à 10kHz. The invention aims to facilitate the realization of a motor vehicle with plastic glazings so as to reduce the total mass of the vehicle and in an economically viable perspective. More particularly, the invention aims to improve the acoustic comfort of a vehicle with such glazing, more particularly to reduce the acoustic transmission over the frequency range 5kHz to 10kHz.
L'invention a pour objet un vitrage en plastique destiné à être monté en appui sur sa périphérie, notamment sur une carrosserie de véhicule automobile, remarquable en ce que le vitrage comprend au moins une portion d'épaisseur variable, ladite portion étant destinée à modifier la vitesse de propagation d'ondes vibratoires dans le vitrage de manière à diminuer la transmission acoustique dudit vitrage sur la plage de fréquences de 5kHz à 10kHz. The invention relates to a plastic glazing intended to be mounted in abutment on its periphery, in particular on a motor vehicle body, remarkable in that the glazing comprises at least one portion of variable thickness, said portion being intended to modify the speed of propagation of vibratory waves in the glazing so as to reduce the acoustic transmission of said glazing over the frequency range 5 kHz to 10 kHz.
Selon un mode avantageux de l'invention, le vitrage est venu de matière, préférentiellement en polycarbonate ou préférentiellement en polyméthacrylate de méthyle. According to an advantageous embodiment of the invention, the glazing is made of material, preferably polycarbonate or preferably polymethyl methacrylate.
Selon un mode avantageux de l'invention, la portion a une épaisseur variant de 15% à 40% de l'épaisseur moyenne du vitrage. According to an advantageous embodiment of the invention, the portion has a thickness varying from 15% to 40% of the average thickness of the glazing.
Selon un mode avantageux de l'invention, la portion s'étend essentiellement à la périphérie du vitrage, ladite portion étant d'épaisseur variable dans une direction périphérique, ladite périphérie ayant une largeur comprise entre 1 % et 15% de la plus grande dimension du vitrage. Selon un mode avantageux de l'invention, la portion est d'épaisseur variable, en outre, dans une direction orthogonale à la direction périphérique. According to an advantageous embodiment of the invention, the portion extends essentially to the periphery of the glazing, said portion being of variable thickness in a peripheral direction, said periphery having a width of between 1% and 15% of the largest dimension. glazing. According to an advantageous embodiment of the invention, the portion is of variable thickness, moreover, in a direction orthogonal to the peripheral direction.
Selon un mode avantageux de l'invention, la portion s'étend dans la partie centrale du vitrage ou sur l'ensemble de la surface du vitrage. Selon un mode avantageux de l'invention, le vitrage est d'une épaisseur moyenne comprise entre 4mm et 8mm, la mesure d'affaiblissement acoustique du vitrage étant améliorée de 0 à 5dB sur la plage de fréquences correspondant à la zone de coïncidence acoustique du vitrage. According to an advantageous embodiment of the invention, the portion extends in the central part of the glazing or on the entire surface of the glazing. According to an advantageous embodiment of the invention, the glazing is of an average thickness of between 4 mm and 8 mm, the acoustic attenuation measurement of the glazing being improved from 0 to 5 dB over the frequency range corresponding to the acoustic coincidence zone of the glazing.
L'invention a également pour objet un procédé de mise à forme d'un vitrage en plastique par moulage à injection, remarquable en ce que le vitrage est conforme à l'invention. The invention also relates to a process for shaping a plastic glazing by injection molding, remarkable in that the glazing is in accordance with the invention.
L'invention a également pour objet un outillage, remarquable en ce qu'il est configuré pour mettre en œuvre le procédé conforme à l'invention, ledit outillage comportant un moule ayant une forme convexe de manière à mettre en forme la face interne du vitrage, ladite face étant destinée à être vers l'intérieur d'un véhicule automobile. The invention also relates to a tool, remarkable in that it is configured to implement the method according to the invention, said tool comprising a mold having a convex shape so as to shape the inner face of the glazing said face being intended to be inwardly of a motor vehicle.
L'invention a également pour objet un véhicule automobile, remarquable en ce qu'il comprend au moins un vitrage en plastique conforme à l'invention, ledit vitrage étant monté sur la carrosserie du véhicule préférentiellement par collage. Les mesures de l'invention sont intéressantes en ce qu'elles permettent de réduire le bruit dans le véhicule sur la plage critique de hautes fréquences de 5kHz à 10kHz. En effet, la variation d'épaisseur dans le vitrage modifie la longueur d'onde, et la vitesse, de l'onde de flexion dans le vitrage, de manière à réduire la chute de pertes de transmission des ondes sonores. La barrière acoustique du vitrage plastique ainsi améliorée facilite la réalisation d'un véhicule automobile plus léger, tout en diminuant la transmission d'ondes acoustiques de l'extérieur du véhicule par rapport à des vitrages en plastique connus. The invention also relates to a motor vehicle, remarkable in that it comprises at least one plastic glazing according to the invention, said glazing being mounted on the vehicle body preferably by gluing. The measurements of the invention are interesting in that they make it possible to reduce the noise in the vehicle over the critical range of high frequencies from 5 kHz to 10 kHz. Indeed, the thickness variation in the glazing changes the wavelength, and speed, of the bending wave in the glazing, so as to reduce the loss of transmission losses of the sound waves. The acoustic barrier of the improved plastic glazing facilitates the realization of a lighter motor vehicle, while reducing the transmission of acoustic waves from the outside of the vehicle compared to known plastic windows.
D'autres caractéristiques et avantages de la présente invention seront mieux compris à l'aide de la description de réalisations exemplaires et des dessins parmi lesquels : - la figure 1 illustre un véhicule automobile muni de vitrages conforme à l'invention ; Other features and advantages of the present invention will be better understood from the description of exemplary embodiments and the drawings among which: - Figure 1 illustrates a motor vehicle with glazing according to the invention;
- la figure 2 est un schéma de principe illustrant la perte de transmission sonore à travers un vitrage ; - la figure 3 est un graphique de principe illustrant la chute de la perte de transmission à travers le vitrage de la figure 2 ; FIG. 2 is a block diagram illustrating the loss of sound transmission through a glazing unit; FIG. 3 is a principle graph illustrating the drop in the transmission loss through the glazing unit of FIG. 2;
- la figure 4 est une vue en coupe radiale d'un vitrage de la figure 1 et une vue agrandie de deux portions du vitrage ; FIG. 4 is a radial sectional view of a glazing unit of FIG. 1 and an enlarged view of two portions of the glazing unit;
- la figure 5 est un graphique illustrant la réduction de la chute des pertes de transmission d'un vitrage selon une réalisation préférée de l'invention ; FIG. 5 is a graph illustrating the reduction of the loss of transmission losses of a glazing unit according to a preferred embodiment of the invention;
- la figure 6 est une vue de face d'un vitrage du véhicule de la figure 1 selon un mode préféré de réalisation ; - Figure 6 is a front view of a glazing of the vehicle of Figure 1 according to a preferred embodiment;
- la figure 7 est une vue en coupe d'une périphérie du vitrage de la figure 6; - Figure 7 is a sectional view of a periphery of the glazing of Figure 6;
- la figure 8 est une vue en coupe radiale du vitrage de la figure 6. La figure 1 est une vue d'un véhicule 2 comprenant au moins un vitrage 4 extérieur conforme à l'invention. Dans un mode préféré de l'invention, le vitrage 4 est en appui sur la carrosserie et fixé par collage sur une feuillure de carrosserie. A titre d'exemple, le vitrage 4 peut être un vitrage de custode ou de toit ou de lunette arrière. Le vitrage 4 est en matériau principal organique 6, il est favorablement en plastique de manière à alléger le véhicule. Il est à titre d'exemple en polycarbonate ou en polyméthacrylate de méthyle. - Figure 8 is a radial sectional view of the window of Figure 6. Figure 1 is a view of a vehicle 2 comprising at least one outer glazing 4 according to the invention. In a preferred embodiment of the invention, the glazing 4 is supported on the body and fixed by gluing on a body rebate. For example, the glazing 4 may be a quarter panel glazing or roof or rear window. The glazing 4 is of organic main material 6, it is favorably plastic so as to lighten the vehicle. It is for example polycarbonate or polymethylmethacrylate.
Les figures 2 et 3 illustrent des principes connus de la barrière acoustique ainsi que de la chute des performances acoustiques d'un vitrage sur une plage de fréquences critiques, des phénomènes qu'il est nécessaire d'appréhender de manière à comprendre leur effet sur l'isolation acoustique d'un véhicule. FIGS. 2 and 3 illustrate known principles of the acoustic barrier as well as the fall in the acoustic performance of a glazing over a critical frequency range, phenomena that must be understood in order to understand their effect on the sound insulation of a vehicle.
La figure 2 représente le vitrage 4 du véhicule 2, vitrage au-dessus duquel est représentée une première flèche illustrant une puissance sonore extérieure et en dessous duquel est représentée une deuxième flèche, de plus petite taille, illustrant une puissance sonore transmise à l'intérieur du véhicule 2. La différence de taille des flèches schématise les pertes par transmission (en dB) « transmission loss » de la puissance sonore à travers un vitrage, plus précisément un vitrage plein et étanche à l'air. Ces pertes se concrétisent par une réduction de bruit entre l'extérieur et l'intérieur, le vitrage devenant communément appelé une barrière acoustique. On peut voir sur l'image de la figure 2 l'onde acoustique de longueur Aair dans l'air ainsi que l'onde vibratoire (ou de flexion) de longueur Afiex dans le vitrage, l'onde acoustique se déplaçant de l'extérieur vers l'intérieur (du haut vers le bas sur l'image) et générant au passage une onde vibratoire dans le vitrage. 2 shows the glazing 4 of the vehicle 2, glazing above which is represented a first arrow illustrating an external sound power and below which is shown a second arrow, of smaller size, illustrating a sound power transmitted inside of the vehicle 2. The difference in size arrows schematizes transmission losses (in dB) "transmission loss" of sound power through a glazing, specifically a solid and airtight glazing. These losses are embodied by a noise reduction between the outside and the inside, the glazing becoming commonly called an acoustic barrier. In the image of FIG. 2, we can see the acoustic wave of length A air in the air as well as the vibratory wave (or flexion) of length A f i ex in the glazing, the acoustic wave moving from the outside to the inside (from top to bottom in the image) and generating a vibratory wave in the glazing.
La figure 3 illustre le phénomène de chute des pertes de transmission d'un vitrage, en d'autres termes un passage plus important du bruit à travers le vitrage, ce phénomène se produisant selon le vitrage sur une certaine plage critique de fréquence f. L'image sur la zone de fréquence critique C (en Hz) illustre de manière générale la soudaineté du phénomène. Le point bas de la chute des pertes correspond physiquement à une coïncidence spatiale et fréquentielle des ondes de flexion (Afiex) dans le vitrage et des ondes acoustiques (Aair) dans l'air enveloppant le vitrage. La vitesse de propagation (ou célérité c ; c = A x f) des ondes sonores à l'extérieur du véhicule égalisant la vitesse de propagation des ondes vibratoires dans le vitrage. Figure 3 illustrates the phenomenon of falling transmission losses of a glazing, in other words a greater passage of noise through the glazing, this phenomenon occurring according to the glazing over a certain critical frequency range f. The image on the critical frequency zone C (in Hz) generally illustrates the suddenness of the phenomenon. The low point of the loss loss corresponds physically to a spatial and frequency coincidence of the bending waves (A f i ex ) in the glazing and acoustic waves (A air ) in the air enveloping the glazing. The speed of propagation (or velocity c; c = A xf) of the sound waves outside the vehicle equalizing the speed of propagation of the vibratory waves in the glazing.
Pour compenser la moins bonne isolation acoustique du vitrage plastique aux basses fréquences, présentée en relation avec l'état de l'art, son épaisseur peut être augmentée tout en contenant la masse du vitrage en deçà de celle d'un vitrage en verre utilisé aujourd'hui. En revanche, la plage de fréquences critique C sur laquelle un bruit accru est transmis est alors décalée de manière désavantageuse de la zone de 10kHz vers une plage de 5kHz à 10kHz plus audible pour l'oreille humaine. Le vitrage en plastique, dans le cadre de l'invention, est configuré de manière à ce qu'il apporte une diminution de la transmission du bruit dans la zone de coïncidence acoustique, plus précisément sur cette plage de fréquences de 5kHz à 10kHz plus audible. To compensate for the poor acoustic insulation of the plastic glazing at low frequencies, presented in relation to the state of the art, its thickness can be increased while containing the mass of the glazing below that of a glass glazing used today. 'hui. On the other hand, the critical frequency range C over which increased noise is transmitted is then disadvantageously shifted from the 10 kHz zone to a range of 5 kHz to 10 kHz more audible to the human ear. The plastic glazing, in the context of the invention, is configured to provide a reduction in the noise transmission in the acoustic coincidence zone, more precisely in this frequency range of 5kHz to 10kHz more audible .
La figure 4 est une vue en coupe radiale du vitrage 4 conforme à l'invention. L'image comprend aussi des agrandissements de deux régions du vitrage. Le vitrage 4 comprend au moins une portion 8 d'épaisseur variable T. AD (représentée sur l'image) correspond à la variation de l'épaisseur variable T dans la portion 8 du vitrage 4. La qualité de la barrière acoustique du vitrage varie, comme vu plus haut, selon la vitesse V de propagation de l'onde vibratoire (ou de flexion) dans le vitrage, elle-même dépendante de la fréquence de l'onde sonore ainsi que de la longueur d'onde de flexion dans le vitrage. Or la non uniformité de l'épaisseur du vitrage influence directement cette vitesse V. En effet, l'onde de flexion (Afiex) dans le vitrage 4 est proportionnelle à la racine carrée de l'épaisseur T du vitrage 4. Ainsi, à cause de l'épaisseur non uniforme de la portion 8, la vitesse de propagation V dans la portion 8 ne l'est pas non plus. La portion 8 n'étant pas limitée dans le vitrage 4, la vitesse de propagation V peut ne pas être uniforme sur toute la surface du vitrage 4. Ainsi, le phénomène de coïncidence acoustique à une fréquence acoustique particulière, phénomène à l'origine de la chute brutale de la perte de transmission acoustique, ne se manifeste pas systématiquement en utilisant un vitrage selon la présente invention. La portion 8 peut s'étendre dans la partie centrale 12 du vitrage 4, elle peut aussi s'étendre sur l'ensemble de la surface 14 du vitrage 4 ou sur sa périphérie 20. AD est de 15% à 40% de l'épaisseur moyenne 16 du vitrage 4. A titre d'exemple, le vitrage 4 est d'une épaisseur variable T= 4mm + 0.5mm à T=4mm - 1 .5mm. Le vitrage 4 peut aussi être, en l'occurrence encore à titre d'exemple, d'une épaisseur variable T=8mm + 1 mm à T=8mm - 3mm. Pour des vitrages 4 d'épaisseur moyenne 16 comprise entre 4 et 8mm, la mesure d'affaiblissement acoustique du vitrage peut être améliorée jusqu'à 5dB sur la plage de fréquences de 5kHz à 10kHz. Figure 4 is a radial sectional view of the glazing unit 4 according to the invention. The image also includes enlargements of two regions of the glazing. The glazing 4 comprises at least one portion 8 of variable thickness T. AD (shown in the image) corresponds to the variation of the variable thickness T in the portion 8 of the glazing 4. The quality of the acoustic barrier of the glazing varies, as seen above, according to the speed V of propagation of the vibratory wave (or bending) in the glazing, itself dependent on the frequency of the sound wave as well as the flexural wavelength in the glazing. However, the non-uniformity of the thickness of the glazing directly influences this speed V. In fact, the bending wave (A f i ex ) in the glazing 4 is proportional to the square root of the thickness T of the glazing 4. Thus because of the non-uniform thickness of the portion 8, the propagation velocity V in the portion 8 is also not. The portion 8 not being limited in the glazing 4, the propagation velocity V may not be uniform over the entire surface of the glazing 4. Thus, the phenomenon of acoustic coincidence at a particular acoustic frequency, a phenomenon at the origin of the sudden drop in acoustic transmission loss is not systematically manifested by using glazing according to the present invention. The portion 8 may extend in the central portion 12 of the glazing 4, it may also extend over the entire surface 14 of the glazing 4 or on its periphery 20. AD is 15% to 40% of the average thickness 16 of the glazing 4. For example, the glazing 4 is of variable thickness T = 4mm + 0.5mm at T = 4mm - 1 .5mm. The glazing 4 can also be, in this case still for example, a variable thickness T = 8mm + 1 mm at T = 8mm - 3mm. For glazing 4 of average thickness 16 between 4 and 8 mm, the sound attenuation measurement of the glazing can be improved up to 5 dB over the frequency range 5 kHz to 10 kHz.
Le vitrage 4 est de préférence réalisé par un procédé de mise à forme par moulage à injection. Un outillage est configuré pour mettre en œuvre le procédé, il comporte un moule ayant une forme convexe de manière à mettre en forme la face interne 18 du vitrage 4, ladite face étant destinée à être vers l'intérieur d'un véhicule automobile. The glazing 4 is preferably made by a molding process by injection molding. A tool is configured to implement the method, it comprises a mold having a convex shape so as to shape the inner face 18 of the glazing 4, said face being intended to be inwardly of a motor vehicle.
La figure 5 illustre par un graphe la réduction de la chute des pertes de transmission d'un vitrage 4 conforme à l'invention. Plus précisément, un premier graphe (en pointillé) représente les pertes de transmission d'un vitrage en plastique classique, le deuxième graphe (en trait plein) représentant les pertes de transmission d'un vitrage en plastique 4 conforme à l'invention. En l'occurrence, l'épaisseur du vitrage de référence est de 6mm, celui conforme à l'invention est d'une épaisseur variant de 4mm à 8mm. On peut observer l'amorce de la chute des pertes de transmission (en dB) du graphe de référence à partir d'une fréquence audible d'environ 5kHz. On peut voir en outre la chute prononcée des pertes du graphe de référence jusqu'à plus de 10kHz. Le deuxième graphe au contraire reste sur un plateau de barrière acoustique équivalent à la réduction acoustique atteinte pour des fréquences comprises entre 4kHz et 5Hz. FIG. 5 illustrates by a graph the reduction of the drop in transmission losses of a glazing unit 4 according to the invention. More precisely, a first graph (in dashed line) represents the transmission losses of a conventional plastic glazing, the second graph (in solid lines) representing the transmission losses of a plastic glazing unit 4 according to the invention. In this case, the thickness of the reference glazing is 6mm, that according to the invention is of a thickness ranging from 4mm to 8mm. We can observe the beginning of the fall of transmission losses (in dB) of the reference graph from an audible frequency of about 5kHz. We can also see the pronounced drop in the reference graph losses to more than 10kHz. The second graph on the contrary remains on a sound barrier plateau equivalent to the acoustic reduction achieved for frequencies between 4kHz and 5Hz.
Les figures suivantes 6 à 8 illustrent un mode préféré de réalisation du vitrage 4 conforme à l'invention. L'exemple de réalisation de l'invention décrit ci-après ne limite pas en soi l'étendue de l'invention revendiquée. The following figures 6 to 8 illustrate a preferred embodiment of the glazing unit 4 according to the invention. The exemplary embodiment of the invention described hereinafter does not limit in itself the scope of the claimed invention.
La figure 6 est une vue de face du vitrage 4 selon un mode préféré de réalisation. La portion 8 d'épaisseur variable T s'étend à la périphérie 20 du vitrage 4. Elle s'étend en l'occurrence sur une partie de la périphérie 20. Alternativement, la portion 8 peut s'étendre sur l'ensemble de la périphérie 20. La portion 8 à la périphérie 20 peut être d'une largeur 22 comprise entre 1 % et 15% de la plus grande dimension 24 du vitrage 4. Dans ce mode de réalisation, la portion 8 est d'épaisseur variable T, en outre, dans une direction orthogonale à la direction périphérique. La portion 8 s'étend alors dans la partie centrale 12 du vitrage 4. Dans un mode de réalisation préféré la portion 8 peut aussi s'étendre sur l'ensemble de la surface 14 du vitrage 4. Figure 6 is a front view of the glazing 4 according to a preferred embodiment. The portion 8 of variable thickness T extends to the periphery 20 of the glazing 4. It extends in this case over a portion of the periphery 20. Alternatively, the portion 8 may extend over the entire periphery 20. The portion 8 at the periphery 20 may be of a width 22 between 1% and 15% of the largest dimension 24 of the glazing 4. In this embodiment, the portion 8 is of variable thickness T, in addition, in a direction orthogonal to the peripheral direction. The portion 8 then extends into the central portion 12 of the glazing 4. In a preferred embodiment the portion 8 may also extend over the entire surface 14 of the glazing 4.
La figure 7 est une vue en coupe le long de la périphérie du vitrage 4 selon un mode préféré de réalisation. La variation d'épaisseur AD1 de la portion 8 d'épaisseur variable T s'étend dans une direction périphérique. Figure 7 is a sectional view along the periphery of the glazing 4 according to a preferred embodiment. The variation in thickness AD1 of the portion 8 of variable thickness T extends in a peripheral direction.
La figure 8 est une vue en coupe radiale au vitrage 4 selon un mode préféré de réalisation. La variation d'épaisseur AD2 de la portion 8 d'épaisseur variable T s'étend dans une direction orthogonale à la direction périphérique. Figure 8 is a radial sectional view to the glazing 4 according to a preferred embodiment. The variation in thickness AD2 of the portion 8 of variable thickness T extends in a direction orthogonal to the peripheral direction.

Claims

REVENDICATIONS
1 . Vitrage en plastique (4) destiné à être monté en appui sur sa périphérie (20), notamment sur une carrosserie de véhicule automobile ;  1. Plastic glazing (4) intended to be mounted in abutment on its periphery (20), in particular on a motor vehicle body;
caractérisé en ce que  characterized in that
le vitrage (4) comprend au moins une portion (8) d'épaisseur variable T, ladite portion (8) étant destinée à modifier la vitesse de propagation d'ondes vibratoires dans le vitrage (4) de manière à diminuer la transmission acoustique dudit vitrage (4) sur la plage de fréquences de 5kHz à 10kHz.  the glazing (4) comprises at least one portion (8) of variable thickness T, said portion (8) being intended to modify the speed of propagation of vibratory waves in the glazing (4) so as to reduce the acoustic transmission of said glazing (4) over the frequency range 5kHz to 10kHz.
2. Vitrage (4) selon la revendication 1 , caractérisé en ce qu'il est venu de matière, préférentiellement en polycarbonate ou préférentiellement en polyméthacrylate de méthyle. 2. Glazing (4) according to claim 1, characterized in that it is made of material, preferably polycarbonate or preferably polymethyl methacrylate.
3. Vitrage (4) selon l'une des revendications 1 et 2, caractérisé en ce que la portion (8) a une épaisseur T variant de 15% à 40% de l'épaisseur moyenne (16) du vitrage (4). 3. Glazing (4) according to one of claims 1 and 2, characterized in that the portion (8) has a thickness T ranging from 15% to 40% of the average thickness (16) of the glazing (4).
4. Vitrage (4) selon l'une des revendications 1 à 3, caractérisé en ce que la portion (8) s'étend essentiellement à la périphérie (20) du vitrage (4), ladite portion (8) étant d'épaisseur variable T dans une direction périphérique, ladite périphérie (20) ayant une largeur (22) comprise entre 1 % et 15% de la plus grande dimension (24) du vitrage (4). 4. Glazing (4) according to one of claims 1 to 3, characterized in that the portion (8) extends substantially to the periphery (20) of the glazing (4), said portion (8) being thick variable T in a peripheral direction, said periphery (20) having a width (22) between 1% and 15% of the largest dimension (24) of the glazing (4).
5. Vitrage (4) selon la revendication 4, caractérisé en ce que la portion (8) est d'épaisseur variable T, en outre, dans une direction orthogonale à la direction périphérique. 5. Glazing (4) according to claim 4, characterized in that the portion (8) is of variable thickness T, in addition, in a direction orthogonal to the peripheral direction.
6. Vitrage (4) selon l'une des revendications 1 à 5, caractérisé en ce que la portion (8) s'étend dans la partie centrale (12) du vitrage ou sur l'ensemble de la surface (14) du vitrage (4). 6. Glazing (4) according to one of claims 1 to 5, characterized in that the portion (8) extends in the central portion (12) of the glazing or on the entire surface (14) of the glazing (4).
7. Vitrage (4) selon l'une des revendications 1 à 6, caractérisé en ce que le vitrage (4) est d'une épaisseur moyenne (16) comprise entre 4mm et 8mm, la mesure d'affaiblissement acoustique du vitrage (4) étant améliorée jusqu'à 5dB sur la plage de fréquences correspondant à la zone de coïncidence acoustique du vitrage (4). 7. Glazing (4) according to one of claims 1 to 6, characterized in that the glazing (4) is of an average thickness (16) between 4mm and 8mm, the measurement of acoustic impairment of the glazing (4 ) being improved to 5 dB over the frequency range corresponding to the acoustic coincidence zone of the glazing (4).
8. Procédé de mise à forme d'un vitrage (4) en plastique par moulage à injection, caractérisé en ce que le vitrage (4) est conforme à l'une des revendications 1 à 7. 8. Process for shaping a plastic glazing (4) by injection molding, characterized in that the glazing (4) is according to one of claims 1 to 7.
9. Outillage de mise à forme, caractérisé en ce qu'il est configuré pour mettre en œuvre le procédé de moulage selon la revendication 8, ledit outillage comportant un moule ayant une forme convexe de manière à mettre en forme la face interne (18) du vitrage, ladite face (18) étant destinée à être vers l'intérieur d'un véhicule automobile. 9. Tooling forming, characterized in that it is configured to implement the molding method according to claim 8, said tool comprising a mold having a convex shape so as to shape the inner face (18) glazing, said face (18) being intended to be inwardly of a motor vehicle.
10. Véhicule automobile, caractérisé en ce qu'il comprend au moins un vitrage (4) en plastique conforme à l'une des revendications 1 à 7, ledit vitrage (4) étant monté sur la carrosserie du véhicule préférentiellement par collage. 10. Motor vehicle, characterized in that it comprises at least one glazing (4) of plastic according to one of claims 1 to 7, said glazing (4) being mounted on the vehicle body preferably by gluing.
PCT/FR2015/050154 2014-02-28 2015-01-22 Plastic automobile glazing with acoustic properties WO2015128554A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
CN201580011193.3A CN106061778B (en) 2014-02-28 2015-01-22 Plastic automotive vehicle window with acoustic characteristic
EP15704353.0A EP3110640A1 (en) 2014-02-28 2015-01-22 Plastic automobile glazing with acoustic properties

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR1451624A FR3018049B1 (en) 2014-02-28 2014-02-28 AUTOMOTIVE GLAZING IN PLASTIC WITH ACOUSTIC PROPERTIES.
FR1451624 2014-02-28

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WO2015128554A1 true WO2015128554A1 (en) 2015-09-03

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CN (1) CN106061778B (en)
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FR2670438A1 (en) * 1990-12-14 1992-06-19 Ppg Industries Inc Windscreen for a collimating driving system
EP0550898A1 (en) * 1992-01-10 1993-07-14 Toyota Jidosha Kabushiki Kaisha Structure of panel
DE10112935A1 (en) * 2001-03-12 2002-10-10 Volkswagen Ag Pane for car side window has tapering, curved shape, angle of taper lying in plane between normal to pane and direction of vision of passenger
DE102004063509A1 (en) * 2004-12-27 2006-07-06 Brose Fahrzeugteile Gmbh & Co. Kommanditgesellschaft, Coburg Window assembly for cabriolet-vehicle, has window pane whose cross section extends in sub region, where cross section is different from cross section of sliding area and pane stands in contact with frame unit in form fit manner over region
DE102005019227A1 (en) * 2005-04-20 2006-10-26 Brose Fahrzeugteile Gmbh & Co. Kommanditgesellschaft, Coburg Movable window pane of lateral door of vehicle, comprising projection in upper area engaging with complementary segment at sealing element

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JPS61177984U (en) * 1985-04-25 1986-11-06

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2670438A1 (en) * 1990-12-14 1992-06-19 Ppg Industries Inc Windscreen for a collimating driving system
EP0550898A1 (en) * 1992-01-10 1993-07-14 Toyota Jidosha Kabushiki Kaisha Structure of panel
DE10112935A1 (en) * 2001-03-12 2002-10-10 Volkswagen Ag Pane for car side window has tapering, curved shape, angle of taper lying in plane between normal to pane and direction of vision of passenger
DE102004063509A1 (en) * 2004-12-27 2006-07-06 Brose Fahrzeugteile Gmbh & Co. Kommanditgesellschaft, Coburg Window assembly for cabriolet-vehicle, has window pane whose cross section extends in sub region, where cross section is different from cross section of sliding area and pane stands in contact with frame unit in form fit manner over region
DE102005019227A1 (en) * 2005-04-20 2006-10-26 Brose Fahrzeugteile Gmbh & Co. Kommanditgesellschaft, Coburg Movable window pane of lateral door of vehicle, comprising projection in upper area engaging with complementary segment at sealing element

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FR3018049A1 (en) 2015-09-04
CN106061778A (en) 2016-10-26
CN106061778B (en) 2019-09-06
FR3018049B1 (en) 2017-10-20
EP3110640A1 (en) 2017-01-04

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