WO2020002804A1 - Motor vehicle windscreen - Google Patents

Motor vehicle windscreen Download PDF

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Publication number
WO2020002804A1
WO2020002804A1 PCT/FR2019/051529 FR2019051529W WO2020002804A1 WO 2020002804 A1 WO2020002804 A1 WO 2020002804A1 FR 2019051529 W FR2019051529 W FR 2019051529W WO 2020002804 A1 WO2020002804 A1 WO 2020002804A1
Authority
WO
WIPO (PCT)
Prior art keywords
windshield according
piezoelectric transducer
windshield
resonant
electrical circuit
Prior art date
Application number
PCT/FR2019/051529
Other languages
French (fr)
Inventor
Marc MICHAU
Original Assignee
Saint-Gobain Glass France
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 Saint-Gobain Glass France filed Critical Saint-Gobain Glass France
Priority to CN201980002594.0A priority Critical patent/CN110870330A/en
Publication of WO2020002804A1 publication Critical patent/WO2020002804A1/en

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R3/00—Circuits for transducers, loudspeakers or microphones
    • H04R3/02—Circuits for transducers, loudspeakers or microphones for preventing acoustic reaction, i.e. acoustic oscillatory feedback
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B17/00—Layered products essentially comprising sheet glass, or glass, slag, or like fibres
    • B32B17/06—Layered products essentially comprising sheet glass, or glass, slag, or like fibres comprising glass as the main or only constituent of a layer, next to another layer of a specific material
    • B32B17/10—Layered products essentially comprising sheet glass, or glass, slag, or like fibres comprising glass as the main or only constituent of a layer, next to another layer of a specific material of synthetic resin
    • B32B17/10005—Layered products essentially comprising sheet glass, or glass, slag, or like fibres comprising glass as the main or only constituent of a layer, next to another layer of a specific material of synthetic resin laminated safety glass or glazing
    • B32B17/10009—Layered products essentially comprising sheet glass, or glass, slag, or like fibres comprising glass as the main or only constituent of a layer, next to another layer of a specific material of synthetic resin laminated safety glass or glazing characterized by the number, the constitution or treatment of glass sheets
    • B32B17/10036—Layered products essentially comprising sheet glass, or glass, slag, or like fibres comprising glass as the main or only constituent of a layer, next to another layer of a specific material of synthetic resin laminated safety glass or glazing characterized by the number, the constitution or treatment of glass sheets comprising two outer glass sheets
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
    • G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
    • G10K11/1785—Methods, e.g. algorithms; Devices
    • G10K11/17861—Methods, e.g. algorithms; Devices using additional means for damping sound, e.g. using sound absorbing panels
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/10—Applications
    • G10K2210/128—Vehicles
    • G10K2210/1282—Automobiles
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/10—Applications
    • G10K2210/129—Vibration, e.g. instead of, or in addition to, acoustic noise
    • G10K2210/1291—Anti-Vibration-Control, e.g. reducing vibrations in panels or beams
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/30—Means
    • G10K2210/321—Physical
    • G10K2210/3211—Active mounts for vibrating structures with means to actively suppress the vibration, e.g. for vehicles
    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K2210/00—Details of active noise control [ANC] covered by G10K11/178 but not provided for in any of its subgroups
    • G10K2210/50—Miscellaneous
    • G10K2210/509—Hybrid, i.e. combining different technologies, e.g. passive and active
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R17/00—Piezoelectric transducers; Electrostrictive transducers
    • H04R17/10—Resonant transducers, i.e. adapted to produce maximum output at a predetermined frequency
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R2440/00—Bending wave transducers covered by H04R, not provided for in its groups
    • H04R2440/05—Aspects relating to the positioning and way or means of mounting of exciters to resonant bending wave panels
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R2499/00—Aspects covered by H04R or H04S not otherwise provided for in their subgroups
    • H04R2499/10—General applications
    • H04R2499/13—Acoustic transducers and sound field adaptation in vehicles

Definitions

  • the invention relates to a motor vehicle windshield to which a base for an accessory such as, for example, an interior mirror or a camera is attached.
  • an accessory such as, for example, an interior mirror or a camera
  • the windshield vibrates, and with it the accessory.
  • an interior mirror this can cause the driver to have a blurred vision in the mirror glass.
  • the vision may also be blurred on the screen, resulting in a degraded driving aid.
  • a windshield consists of laminated glazing comprising two transparent substrates between which a viscoelastic interlayer is disposed.
  • a so-called acoustic PVB interlayer instead of a standard PVB interlayer.
  • the acoustic PVB interlayer is for example a three-layer interlayer comprising two external PVB layers having ordinary acoustic properties (PVB standard) between which is placed a central layer which is less rigid than the external layers, which is based on PVB and which contains more plasticizer than standard PVB.
  • PVB standard ordinary acoustic properties
  • the natural frequencies of the windshield between 10 Hz and 400 Hz, are not always well damped, which can cause vibration of the accessory and therefore of the glass of the rear view mirror or the camera.
  • the invention provides a motor vehicle windshield comprising two transparent substrates connected to each other by an interlayer of viscoelastic material, at least one of the substrates comprising on its surface an electromechanical resonator disposed in the immediate vicinity of a location for an accessory base such as an interior mirror or a camera.
  • the electromechanical resonator comprises a piezoelectric transducer and a resonant electrical circuit, connected together.
  • the resonant electrical circuit is a passive or semi-passive circuit comprising at least one inductor, the inductor being either a coil or a synthetic inductor.
  • the resonant electrical circuit further comprises a negative synthesis capacitance.
  • the resonant electrical circuit further includes a resistor.
  • the resonant electrical circuit is also adaptive by adjusting the inductance and / or the capacitance.
  • the resonant electrical circuit is a multi-resonant circuit.
  • the electromechanical resonator comprises a second piezoelectric transducer which is located on the other face of the trans parent substrate, opposite the first piezoelectric transducer, and which is connected to the same resonant electrical circuit as the first transducer piezoelectric.
  • the piezoelectric transducer has a surface of between 1 and 100 cm 2 , preferably between 30 and 70 cm 2 .
  • the piezoelectric transducer has a total thickness of between 1 ⁇ m and 2 mm, preferably between 500 ⁇ m and 1.5 mm, or even between 800 ⁇ m and 1.2 mm.
  • the piezoelectric transducer is transparent and preferably based on zinc oxide, or on titanium oxide and on barium of BaTi03 type, or on aluminum nitride, or on Titano-Zirconate of Lead (PZT ), or of polyvinylidene fluoride (PVDF), or of Titano-Zirconate of Lead doped with Lan thane (PLZT), or of block copolymer of poly (styrene-b-isoprene).
  • the piezoelectric transducer comprises a piezoelectric element, for example in the form of a thin layer, situated between two electrodes, for example in the form of a thin layer, at least one dielectric layer, for example thin, preferably being arranged between each electrode and the piezoelectric element.
  • the two electrodes are transparent and preferably consist of a stack of thin layers comprising at least one thin layer of transparent conductive oxide, for example ti tane oxide, and / or a thin metallic layer.
  • the piezoelectric transducer is fixed on a face of the substrate which is opposite the interlayer.
  • Figure 1 shows a front view of a windshield according to the invention
  • FIGS. 2 and 3 are a detailed sectional view of a windshield according to the invention, according to two separate embodiments;
  • Figure 5 shows an example of negative synthesis capacitance.
  • a transparent substrate is defined as a substrate with a glass function, in particular in soda-lime glass or in plastic, for example of the polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC), polymethyl methacrylate (PMMA) type or still poly (ethylene-co-tetrafluoroethylene) (ETFE).
  • PET polyethylene terephthalate
  • PEN polyethylene naphthalate
  • PC polycarbonate
  • PMMA polymethyl methacrylate
  • ETFE ethylene-co-tetrafluoroethylene
  • transparent defines a total transmission (direct and diffuse) greater than 1%, and preferably greater than 40%, for wavelengths visible to the human eye, from a spectrum composed of discrete lines. and / or continuous. These visible wavelengths are between 350 and 800 nm.
  • a piezoelectric transducer comprises a piezoelectric material placed between two electrodes and is adapted to transform an electrical signal into a mechanical movement and vice versa.
  • the invention relates to a motor vehicle windshield comprising two transparent substrates connected to each other by an interlayer of viscoelastic material. At least one of the substrates comprises on its surface an electromechanical resonator arranged in the immediate vicinity of a location for an accessory base such as an interior rearview mirror or a camera.
  • the electromechanical resonator makes it possible to absorb the vibrations of the windshield locally in the immediate vicinity of the base of the accessory. This allows then that the accessory, and therefore the mirror glass or the camera, no longer vibrates or does not vibrate sufficiently to make the vision blurry in the mirror glass or does not disturb the image captured by the camera.
  • FIG. 1 shows a front view of a windshield according to the invention.
  • the windshield 1 of a motor vehicle is a laminated glazing comprising two transparent substrates 2, 3 connected together by an interlayer 4 made of viscoelastic material.
  • Each substrate 2, 3 is made of organic or inorganic glass.
  • At least one of the substrates 2, 3 comprises, on at least one of its faces, an electromechanical resonator 10 which is disposed in the immediate vicinity of a location 7 for an accessory base such as an interior mirror or a camera.
  • the electromechanical resonator 10 is preferably positioned on a screen-printed part 8 of the windshield 1, so as to be as little visible as possible, or even not to be visible at all.
  • the base of the accessory is itself generally positioned on a screen-printed part 8 of the windshield 1.
  • the invention makes it possible to generate an attenuation peak which corresponds best to the vibration peak, in order to provide a vibrational response to the local vibratory behavior of the windshield.
  • FIGS. 2 and 3 are a detailed sectional view of a windshield according to the invention, according to two separate embodiments.
  • the electromechanical resonator 10 preferably comprises a piezoelectric transducer 5 and a resonant electrical circuit 6, which are connected together, preferably by a pair of conductive wires or conductive tracks 9a, 9b.
  • the inventors have demonstrated that the piezoelectric transducer 5 connected to a resonant electric circuit 6 is equivalent to a spring / mass system, but much lighter. This is very advantageous because it allows not to weigh down the windshield, and therefore not to induce an increase in the consumption of the vehicle.
  • the piezoelectric transducer 5 is preferably transparent but the resonant electric circuit 6 is not. Thus, at least the resonant electrical circuit 6 is preferably positioned on a screen-printed part 8 of the windshield 1.
  • the piezoelectric transducer 5 is located on an external face of the windshield, preferably that which is intended to be turned towards the interior of the vehicle.
  • the piezoelectric transducer 5 is located on an internal face of the windshield, between the substrate 2 and the interlayer 4. This makes it possible to protect the transducer 5 and to position it more precisely at the place where the vibration level should be reduced.
  • the resonant electrical circuit 6 is either fixed on an external face of the windshield, or offset, for example in the base of the accessory or even outside the windshield.
  • the resonant electrical circuit 6 comprises at least one inductor, the inductor being either a coil or a synthetic inductor.
  • the piezoelectric transducer 5 acts as a capacitor.
  • the capacity is the equivalent of the spring of a spring / mass system and the inductance is the equivalent of the mass of a spring / mass system.
  • the synthetic inductor is however preferred to the coil.
  • the synthetic inductor is, for example, of the Antoniou type. An example of synthetic inductance is shown in Figure 4.
  • the resonant electrical circuit 6 can also comprise a negative synthesis capacitance, which is chosen as a function of the capacitance of the piezoelectric transducer 5.
  • a negative synthesis capacitance which is chosen as a function of the capacitance of the piezoelectric transducer 5.
  • the negative synthesis capacitance makes it possible to have an equivalent equivalent capacitance C eq which is then less than the capacitance of the piezoelectric transducer 5 alone, which makes it possible to better meet the needs in terms of local attenuation of a vibration peak.
  • An example of negative capacitance is shown in Figure 5.
  • the frequency band which makes it possible to attenuate, or even suppress, the vibrations of the windshield locally is determined using the following formula:
  • ⁇ R is the resonance frequency and corresponds to the center frequency of the peak of frequencies on which we want to attenuate / suppress the vibrations locally.
  • L eq is the value of the inductance carried out with a conventional coil or with a synthesis inductance, and C eq is equal, either to the capacitance of the transparent piezoelectric transducer alone, or to the sum of the capacitance of the transparent piezoelectric transducer and negative synthesis capacitance. In order to guarantee the stability of the system, it is necessary to check C eq > 0.
  • the value of the synthesis inductance, and possibly that of the negative capacitance, are then fixed as a function of the resonant frequency that one wishes, for example 100 Hz if one wishes to attenuate / suppress vibrations locally. on a frequency band around 100 Hz.
  • the attenuation peak is centered around a resonant frequency between 10 Hz and 400 Hz depending on the vibration system of the windshield once it is installed on a vehicle.
  • the resonant electrical circuit 6 can also comprise a resistor.
  • the presence of a resistor in the resonant electrical circuit makes it possible to adapt the quality factor of the resonance and makes it possible to adapt as best as possible to the vibratory peak of the windshield once it is installed on a vehicle.
  • the resonant electrical circuit 6 can also be adaptive by adjusting the synthesis inductance and / or the synthesis capacitance. This adjustment is made according to the preferred frequency band according to the formula cited above. To do this, the synthesis inductance circuit and / or that of the synthesis capacitance include, for example, an adjustable resistance. The fact that the resonant electrical circuit 6 is adaptive makes it possible to adapt even better to the vibratory peak of the windshield once it is installed on a vehicle.
  • the resonant electrical circuit 6 can also be a multi-resonant circuit. This allows to multiply the frequency bands on which we want to attenuate / suppress vibrations locally, by having at least two attenuation peaks.
  • the resonant electrical circuit may for example comprise at least two coils or two synthesis inductors, preferably connected two by two by a capacitance to avoid interference between the different inductances.
  • the multi-resonant electrical circuit preferably comprises a maximum of five resonances.
  • the resonant electrical circuit 6 is a passive or semi-passive circuit. Indeed, it is passive in the case where it comprises only one or more coils and it is semi-passive in the case where it comprises at least one synthetic component. Indeed, the components of synthesis include operational amplifiers which, to function, need to be supplied by a small quantity of electric current.
  • the system of the invention therefore has nothing to do with active attenuation.
  • the piezoelectric transducer 5, connected to the resonant electric circuit 6, captures the local movements of the substrate 2, 3 and modifies these movements in response, passively or semi-passively, as a spring / mass system, which is also a passive system. As we do not bring energy into the system, there is no risk of having instabilities, unlike an active control system.
  • the electromechanical resonator 10 may comprise a second piezoelectric transducer which is situated on the other face of the transparent substrate 2, 3, opposite the first piezoelectric transducer 5, and which is connected to the same resonant electrical circuit 6 as the first piezoelectric transducer 5.
  • two piezoelectric transducers seeing the same deformation of the substrate 2, 3, since they are in the same place of the latter, are connected to the same resonant electrical circuit 6. This makes it possible to increase the efficiency of the system and to increase the width of the frequency band over which the vibrations are to be attenuated / suppressed locally.
  • the piezoelectric transducer 5 has for example a surface of between 1 and 100 cm 2 , preferably between 30 and 70 cm 2 so as to have the most adequate amplitude of attenuation peak possible.
  • the piezoelectric transducer 5 has for example a total thickness comprised between 1 pm and 2 mm, preferably between 500 pm and 1.5 mm, or even between 800 pm and 1.2 mm so as to have an amplitude of attenuation peak as adequate as possible.
  • the piezoelectric transducer 5 is preferably transparent and for example based on zinc oxide, or on titanium and barium oxide of the BaTiO 3 type, or on aluminum nitride, or on Lead Zirconate (PZT), or of polyvinylidene fluoride (PVDF), or of Titano-Zirconate of Lead doped with Lanthanum (PLZT), or of block copolymer of poly (styrene-b-isoprene).
  • the piezoelectric transducer 5 comprises a piezoelectric element, which can for example be in the form of a thin layer, situated between two electrodes, which can for example be in the form of a thin layer. At least one dielectric layer is preferably disposed between each electrode and the piezoelectric element.
  • the two electrodes are preferably transparent and preferably consist of a stack of thin layers comprising at least one thin layer of transparent conductive oxide, for example titanium oxide, and / or a thin metallic layer.
  • Each first electrode is connected to one of the conductive wires or to one of the conductive tracks 9a, 9b and each second electrode is connected to the other conductive wire or conductive track 9b, 9a.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Health & Medical Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Otolaryngology (AREA)
  • Signal Processing (AREA)
  • Fittings On The Vehicle Exterior For Carrying Loads, And Devices For Holding Or Mounting Articles (AREA)
  • Apparatuses For Generation Of Mechanical Vibrations (AREA)

Abstract

The invention relates to a motor vehicle windscreen comprising two transparent substrates (2, 3) that are connected together by an insert (4) made of viscoelastic material, at least one of the substrates (2, 3) comprising, on its surface, an electromechanical resonator (10) disposed in the immediate vicinity of a position (7) for a base of an accessory such as a rear-view mirror or a camera. The invention makes it possible to attenuate, or even eliminate, vibrations of the glass of the rear-view mirror or of the camera.

Description

PARE-BRISE DE VEHICULE AUTOMOBILE  MOTOR VEHICLE WINDSHIELD
L’invention concerne un pare-brise de véhicule automobile sur lequel est des tinée à être fixée une embase pour un accessoire tel que, par exemple, un rétrovi seur intérieur ou une caméra. Lorsque le véhicule roule, le pare-brise vibre, et avec lui l’accessoire. Dans le cas d’un rétroviseur intérieur, cela peut entraîner une vision floue dans la vitre du rétroviseur pour le conducteur. Dans le cas d’une caméra, la vision peut également être floue sur l’écran, entraînant une aide à la conduite dé gradée. The invention relates to a motor vehicle windshield to which a base for an accessory such as, for example, an interior mirror or a camera is attached. When the vehicle is moving, the windshield vibrates, and with it the accessory. In the case of an interior mirror, this can cause the driver to have a blurred vision in the mirror glass. In the case of a camera, the vision may also be blurred on the screen, resulting in a degraded driving aid.
Un pare-brise est constitué d’un vitrage feuilleté comprenant deux substrats transparents entre lesquels est disposé un intercalaire viscoélastique. Afin de limiter les vibrations du pare-brise, qui génèrent du bruit, il est connu d’utiliser un interca laire en PVB dit acoustique au lieu d’un intercalaire en PVB standard. L’intercalaire en PVB acoustique est par exemple un intercalaire tri-couche comprenant deux couches externes en PVB ayant des propriétés acoustiques banales (PVB stan dard) entre lesquelles est disposée une couche centrale moins rigide que les couches externes, qui est à base de PVB et qui contient plus de plastifiant que le PVB standard. Toutefois, ce type d’intercalaire ne permet pas d’amortir les ondes acoustiques de façon équivalente sur l’ensemble des fréquences audibles.  A windshield consists of laminated glazing comprising two transparent substrates between which a viscoelastic interlayer is disposed. In order to limit the vibrations of the windshield, which generate noise, it is known to use a so-called acoustic PVB interlayer instead of a standard PVB interlayer. The acoustic PVB interlayer is for example a three-layer interlayer comprising two external PVB layers having ordinary acoustic properties (PVB standard) between which is placed a central layer which is less rigid than the external layers, which is based on PVB and which contains more plasticizer than standard PVB. However, this type of interlayer does not dampen the acoustic waves in an equivalent manner over all the audible frequencies.
Ainsi, les fréquences propres du pare-brise, comprises entre 10 Hz et 400 Hz, ne sont pas toujours bien amorties, ce qui peut entraîner une vibration de l’ac cessoire et donc de la vitre du rétroviseur intérieur ou de la caméra.  Thus, the natural frequencies of the windshield, between 10 Hz and 400 Hz, are not always well damped, which can cause vibration of the accessory and therefore of the glass of the rear view mirror or the camera.
Il y a donc un besoin pour un pare-brise de véhicule automobile qui permette d’atténuer, voire de supprimer, les vibrations de l’accessoire.  There is therefore a need for a motor vehicle windshield which makes it possible to attenuate, or even eliminate, the vibrations of the accessory.
Pour cela, l’invention propose un pare-brise de véhicule automobile compre nant deux substrats transparents reliés entre eux par un intercalaire en matériau viscoélastique, au moins un des substrats comprenant à sa surface un résonateur électromécanique disposé à proximité immédiate d’un emplacement pour une em base d’accessoire tel qu’un rétroviseur intérieur ou une caméra.  For this, the invention provides a motor vehicle windshield comprising two transparent substrates connected to each other by an interlayer of viscoelastic material, at least one of the substrates comprising on its surface an electromechanical resonator disposed in the immediate vicinity of a location for an accessory base such as an interior mirror or a camera.
Selon une autre particularité, le résonateur électromécanique comprend un transducteur piézoélectrique et un circuit électrique résonant, reliés entre eux.  According to another particular feature, the electromechanical resonator comprises a piezoelectric transducer and a resonant electrical circuit, connected together.
Selon une autre particularité, le circuit électrique résonant est un circuit passif ou semi-passif comprenant au moins une inductance, l’inductance étant, soit une bobine, soit une inductance de synthèse. Selon une autre particularité, le circuit électrique résonant comprend en outre une capacitance de synthèse négative. According to another particular feature, the resonant electrical circuit is a passive or semi-passive circuit comprising at least one inductor, the inductor being either a coil or a synthetic inductor. According to another particular feature, the resonant electrical circuit further comprises a negative synthesis capacitance.
Selon une autre particularité, le circuit électrique résonant comprend en outre une résistance.  In another feature, the resonant electrical circuit further includes a resistor.
Selon une autre particularité, le circuit électrique résonant est en outre adap tatif par réglage de l’inductance et/ou de la capacitance.  According to another particular feature, the resonant electrical circuit is also adaptive by adjusting the inductance and / or the capacitance.
Selon une autre particularité, le circuit électrique résonant est un circuit multi- résonnant.  According to another particular feature, the resonant electrical circuit is a multi-resonant circuit.
Selon une autre particularité, le résonateur électromécanique comprend un second transducteur piézoélectrique qui est situé sur l’autre face du substrat trans parent, en vis-à-vis du premier transducteur piézoélectrique, et qui est relié au même circuit électrique résonant que le premier transducteur piézoélectrique.  According to another particular feature, the electromechanical resonator comprises a second piezoelectric transducer which is located on the other face of the trans parent substrate, opposite the first piezoelectric transducer, and which is connected to the same resonant electrical circuit as the first transducer piezoelectric.
Selon une autre particularité, le transducteur piézoélectrique a une surface comprise entre 1 et 100 cm2, de préférence entre 30 et 70 cm2. According to another particular feature, the piezoelectric transducer has a surface of between 1 and 100 cm 2 , preferably between 30 and 70 cm 2 .
Selon une autre particularité, le transducteur piézoélectrique a une épaisseur totale comprise entre 1 pm et 2 mm, de préférence entre 500 pm et 1 ,5 mm, voire entre 800 pm et 1 ,2 mm.  According to another particular feature, the piezoelectric transducer has a total thickness of between 1 μm and 2 mm, preferably between 500 μm and 1.5 mm, or even between 800 μm and 1.2 mm.
Selon une autre particularité, le transducteur piézoélectrique est transparent et de préférence à base d’oxyde de zinc, ou d’oxyde de titane et de baryum de type BaTi03, ou de nitrure d’aluminium, ou de Titano-Zirconate de Plomb (PZT), ou de polyfluorure de vinylidène (PVDF), ou de Titano-Zirconate de Plomb dopé au Lan thane (PLZT), ou encore de copolymère à bloc de poly(styrène-b-isoprène).  According to another particularity, the piezoelectric transducer is transparent and preferably based on zinc oxide, or on titanium oxide and on barium of BaTi03 type, or on aluminum nitride, or on Titano-Zirconate of Lead (PZT ), or of polyvinylidene fluoride (PVDF), or of Titano-Zirconate of Lead doped with Lan thane (PLZT), or of block copolymer of poly (styrene-b-isoprene).
Selon une autre particularité, le transducteur piézoélectrique comprend un élément piézoélectrique, par exemple sous forme de couche mince, situé entre deux électrodes, par exemple sous forme de couche mince, au moins une couche diélec trique, par exemple mince, étant de préférence disposée entre chaque électrode et l’élément piézoélectrique.  According to another particular feature, the piezoelectric transducer comprises a piezoelectric element, for example in the form of a thin layer, situated between two electrodes, for example in the form of a thin layer, at least one dielectric layer, for example thin, preferably being arranged between each electrode and the piezoelectric element.
Selon une autre particularité, les deux électrodes sont transparentes et de préférence constituées d’un empilement de couches minces comprenant au moins une couche mince en oxyde transparent conducteur, par exemple en oxyde de ti tane, et/ou une couche mince métallique.  According to another particular feature, the two electrodes are transparent and preferably consist of a stack of thin layers comprising at least one thin layer of transparent conductive oxide, for example ti tane oxide, and / or a thin metallic layer.
Selon une autre particularité, le transducteur piézoélectrique est fixé sur une face du substrat qui est en vis-à-vis de l’intercalaire. D’autres caractéristiques et avantages de l’invention vont à présent être dé crits en regard des dessins sur lesquels : According to another particularity, the piezoelectric transducer is fixed on a face of the substrate which is opposite the interlayer. Other characteristics and advantages of the invention will now be described with reference to the drawings in which:
• La figure 1 représente une vue de face d’un pare-brise selon l’inven tion ;  • Figure 1 shows a front view of a windshield according to the invention;
• Les figures 2 et 3 sont une vue de détail en coupe d’un pare-brise selon l’invention, selon deux modes de réalisation distincts ;  • Figures 2 and 3 are a detailed sectional view of a windshield according to the invention, according to two separate embodiments;
• La figure 4 représente un exemple d’inductance de synthèse ;  • Figure 4 shows an example of synthesis inductance;
• La figure 5 représente un exemple de capacitance de synthèse néga tive.  • Figure 5 shows an example of negative synthesis capacitance.
Les numéros de référence qui sont identiques sur les différentes figures re présentent des éléments similaires ou identiques.  The reference numbers which are identical in the various figures re show similar or identical elements.
Un substrat transparent est défini comme un substrat à fonction verrière, no tamment en verre sodo-calcique ou en plastique par exemple de type polyéthylène téréphtalate (PET), polyéthylène naphtalate (PEN), polycarbonate (PC), polymé- thylmétacrylate (PMMA) ou encore poly(éthylène-co-tetrafluoroéthylène) (ETFE).  A transparent substrate is defined as a substrate with a glass function, in particular in soda-lime glass or in plastic, for example of the polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC), polymethyl methacrylate (PMMA) type or still poly (ethylene-co-tetrafluoroethylene) (ETFE).
Le terme « transparent » définit une transmission totale (directe et diffuse) supérieure à 1 %, et de préférence supérieure à 40 %, pour des longueurs d’onde visibles de l’œil humain, à partir d’un spectre composé de raies discrètes et/ou con tinues. Ces longueurs d’onde visibles sont comprises entre 350 et 800 nm.  The term "transparent" defines a total transmission (direct and diffuse) greater than 1%, and preferably greater than 40%, for wavelengths visible to the human eye, from a spectrum composed of discrete lines. and / or continuous. These visible wavelengths are between 350 and 800 nm.
Un transducteur piézoélectrique comprend un matériau piézoélectrique dis posé entre deux électrodes et est adapté à transformer un signal électrique en un mouvement mécanique et inversement.  A piezoelectric transducer comprises a piezoelectric material placed between two electrodes and is adapted to transform an electrical signal into a mechanical movement and vice versa.
L’invention se rapporte à un pare-brise de véhicule automobile compre nant deux substrats transparents reliés entre eux par un intercalaire en matériau viscoélastique. Au moins un des substrats comprend à sa surface un résonateur électromécanique disposé à proximité immédiate d’un emplacement pour une em base d’accessoire tel qu’un rétroviseur intérieur ou une caméra.  The invention relates to a motor vehicle windshield comprising two transparent substrates connected to each other by an interlayer of viscoelastic material. At least one of the substrates comprises on its surface an electromechanical resonator arranged in the immediate vicinity of a location for an accessory base such as an interior rearview mirror or a camera.
Ainsi, le résonateur électromécanique permet d’absorber les vibrations du pare-brise localement à proximité immédiate de l’embase de l’accessoire. Cela per met alors que l’accessoire, et donc la vitre du rétroviseur ou la caméra, ne vibre plus ou ne vibre pas de façon suffisante pour rendre la vision floue dans la vitre du ré troviseur ou ne perturbe pas l’image captée par la caméra.  Thus, the electromechanical resonator makes it possible to absorb the vibrations of the windshield locally in the immediate vicinity of the base of the accessory. This allows then that the accessory, and therefore the mirror glass or the camera, no longer vibrates or does not vibrate sufficiently to make the vision blurry in the mirror glass or does not disturb the image captured by the camera.
La figure 1 représente une vue de face d’un pare-brise selon l’invention. Le pare-brise 1 de véhicule automobile est un vitrage feuilleté comprenant deux substrats 2, 3 transparents reliés entre eux par un intercalaire 4 en matériau viscoélastique. Chaque substrat 2, 3 est en verre organique ou inorganique. Au moins un des substrats 2, 3 comprend, sur au moins une de ses faces, un résona teur électromécanique 10 qui est disposé à proximité immédiate d’un emplacement 7 pour une embase d’accessoire tel qu’un rétroviseur intérieur ou une caméra. Figure 1 shows a front view of a windshield according to the invention. The windshield 1 of a motor vehicle is a laminated glazing comprising two transparent substrates 2, 3 connected together by an interlayer 4 made of viscoelastic material. Each substrate 2, 3 is made of organic or inorganic glass. At least one of the substrates 2, 3 comprises, on at least one of its faces, an electromechanical resonator 10 which is disposed in the immediate vicinity of a location 7 for an accessory base such as an interior mirror or a camera.
Le résonateur électromécanique 10 est de préférence positionné sur une par tie sérigraphiée 8 du pare-brise 1 , afin d’être le moins visible possible, voire de ne pas être visible du tout. L’embase de l’accessoire est elle-même généralement po sitionnée sur une partie sérigraphiée 8 du pare-brise 1 .  The electromechanical resonator 10 is preferably positioned on a screen-printed part 8 of the windshield 1, so as to be as little visible as possible, or even not to be visible at all. The base of the accessory is itself generally positioned on a screen-printed part 8 of the windshield 1.
L’invention permet de générer un pic d’atténuation qui corresponde au mieux avec le pic de vibration, afin d’apporter une réponse vibratoire au comportement vibratoire local du pare-brise.  The invention makes it possible to generate an attenuation peak which corresponds best to the vibration peak, in order to provide a vibrational response to the local vibratory behavior of the windshield.
Les figures 2 et 3 sont une vue de détail en coupe d’un pare-brise selon l’in vention, selon deux modes de réalisation distincts.  Figures 2 and 3 are a detailed sectional view of a windshield according to the invention, according to two separate embodiments.
Le résonateur électromécanique 10 comprend de préférence un transducteur piézoélectrique 5 et un circuit électrique résonant 6, qui sont reliés entre eux, de préférence par une paire de fils conducteurs ou de pistes conductrices 9a, 9b. Les inventeurs ont mis en évidence que le transducteur piézoélectrique 5 relié à un cir cuit électrique résonnant 6 est équivalent à un système ressort/masse, mais beau coup plus léger. C’est très avantageux car cela permet de ne pas alourdir le pare- brise, et donc de ne pas induire une augmentation de la consommation du véhicule.  The electromechanical resonator 10 preferably comprises a piezoelectric transducer 5 and a resonant electrical circuit 6, which are connected together, preferably by a pair of conductive wires or conductive tracks 9a, 9b. The inventors have demonstrated that the piezoelectric transducer 5 connected to a resonant electric circuit 6 is equivalent to a spring / mass system, but much lighter. This is very advantageous because it allows not to weigh down the windshield, and therefore not to induce an increase in the consumption of the vehicle.
Le transducteur piézoélectrique 5 est de préférence transparent mais le cir cuit électrique résonant 6 ne l’est pas. Ainsi, au moins le circuit électrique résonant 6 est de préférence positionné sur une partie sérigraphiée 8 du pare-brise 1 .  The piezoelectric transducer 5 is preferably transparent but the resonant electric circuit 6 is not. Thus, at least the resonant electrical circuit 6 is preferably positioned on a screen-printed part 8 of the windshield 1.
Sur la figure 2, le transducteur piézoélectrique 5 est situé sur une face ex terne du pare-brise, de préférence celle qui est destinée à être tournée vers l’inté rieur du véhicule.  In FIG. 2, the piezoelectric transducer 5 is located on an external face of the windshield, preferably that which is intended to be turned towards the interior of the vehicle.
Sur la figure 3, le transducteur piézoélectrique 5 est situé sur une face interne du pare-brise, entre le substrat 2 et l’intercalaire 4. Cela permet de protéger le trans ducteur 5 et de le positionner plus précisément à l’endroit où le niveau vibratoire doit être réduit. Dans les deux modes de réalisation, le circuit électrique résonant 6 est, soit fixé sur une face externe du pare-brise, soit déporté, par exemple dans l’embase de l’accessoire ou même en dehors du pare-brise. In FIG. 3, the piezoelectric transducer 5 is located on an internal face of the windshield, between the substrate 2 and the interlayer 4. This makes it possible to protect the transducer 5 and to position it more precisely at the place where the vibration level should be reduced. In both embodiments, the resonant electrical circuit 6 is either fixed on an external face of the windshield, or offset, for example in the base of the accessory or even outside the windshield.
Tout le reste est identique sur les deux figures.  Everything else is identical in the two figures.
Le circuit électrique résonant 6 comprend au moins une inductance, l’induc tance étant, soit une bobine, soit une inductance de synthèse. Le transducteur pié zoélectrique 5 agit comme une capacité. La capacité est l’équivalent du ressort d’un système ressort/masse et l’inductance est l’équivalent de la masse d’un système ressort/masse. Pour gagner en place et en poids, l’inductance de synthèse est tou tefois préférée à la bobine. L’inductance de synthèse est par exemple du type An- toniou. Un exemple d’inductance de synthèse est représenté sur la figure 4.  The resonant electrical circuit 6 comprises at least one inductor, the inductor being either a coil or a synthetic inductor. The piezoelectric transducer 5 acts as a capacitor. The capacity is the equivalent of the spring of a spring / mass system and the inductance is the equivalent of the mass of a spring / mass system. To gain space and weight, the synthetic inductor is however preferred to the coil. The synthetic inductor is, for example, of the Antoniou type. An example of synthetic inductance is shown in Figure 4.
Le circuit électrique résonant 6 peut en outre comprendre une capacitance de synthèse négative, qui est choisie en fonction de la capacitance du transducteur piézoélectrique 5. En effet, la capacitance du transducteur piézoélectrique 5 est parfois trop élevée par rapport aux besoins. La capacitance de synthèse négative permet d’avoir une capacitance résultante équivalente Ceq qui est alors inférieure à la capacitance du transducteur piézoélectrique 5 seul, ce qui permet de mieux ré pondre aux besoins en termes d’atténuation locale d’un pic de vibration . Un exemple de capacitance négative est représenté sur la figure 5. The resonant electrical circuit 6 can also comprise a negative synthesis capacitance, which is chosen as a function of the capacitance of the piezoelectric transducer 5. In fact, the capacitance of the piezoelectric transducer 5 is sometimes too high compared to the requirements. The negative synthesis capacitance makes it possible to have an equivalent equivalent capacitance C eq which is then less than the capacitance of the piezoelectric transducer 5 alone, which makes it possible to better meet the needs in terms of local attenuation of a vibration peak. An example of negative capacitance is shown in Figure 5.
La bande de fréquences qui permet d’atténuer, voire de supprimer, les vibra tions du pare-brise localement est déterminée à l’aide de la formule suivante :
Figure imgf000007_0001
The frequency band which makes it possible to attenuate, or even suppress, the vibrations of the windshield locally is determined using the following formula:
Figure imgf000007_0001
où†R est la fréquence de résonance et correspond à la fréquence centrale du pic de fréquences sur lequel on veut atténuer/supprimer les vibrations localement. Leq est la valeur de l’inductance réalisée avec une bobine classique ou avec une inductance de synthèse, et Ceq est égale, soit à la capacitance du transducteur pié zoélectrique transparent seul, soit à la somme de la capacitance du transducteur piézoélectrique transparent et de la capacitance de synthèse négative. Afin de ga rantir la stabilité du système, il faut vérifier Ceq>0. where † R is the resonance frequency and corresponds to the center frequency of the peak of frequencies on which we want to attenuate / suppress the vibrations locally. L eq is the value of the inductance carried out with a conventional coil or with a synthesis inductance, and C eq is equal, either to the capacitance of the transparent piezoelectric transducer alone, or to the sum of the capacitance of the transparent piezoelectric transducer and negative synthesis capacitance. In order to guarantee the stability of the system, it is necessary to check C eq > 0.
La valeur de l’inductance de synthèse, et éventuellement celle de la capaci tance négative, sont alors fixées en fonction de la fréquence de résonance que l’on souhaite, par exemple 100 Hz si l’on souhaite atténuer/supprimer les vibrations lo calement sur une bande de fréquences autour de 100 Hz. Le pic d’atténuation est centré autour d’une fréquence de résonnance comprise entre 10 Hz et 400 Hz en fonction du système vibratoire du pare-brise une fois qu’il sera installé sur un véhi cule. The value of the synthesis inductance, and possibly that of the negative capacitance, are then fixed as a function of the resonant frequency that one wishes, for example 100 Hz if one wishes to attenuate / suppress vibrations locally. on a frequency band around 100 Hz. The attenuation peak is centered around a resonant frequency between 10 Hz and 400 Hz depending on the vibration system of the windshield once it is installed on a vehicle.
Le circuit électrique résonant 6 peut en outre comprendre une résistance. La présence d’une résistance dans le circuit électrique résonant permet d’adapter le facteur de qualité de la résonance et permet de s’adapter au mieux au pic vibratoire du pare-brise une fois qu’il sera installé sur un véhicule.  The resonant electrical circuit 6 can also comprise a resistor. The presence of a resistor in the resonant electrical circuit makes it possible to adapt the quality factor of the resonance and makes it possible to adapt as best as possible to the vibratory peak of the windshield once it is installed on a vehicle.
Le circuit électrique résonant 6 peut en outre être adaptatif par réglage de l’inductance de synthèse et/ou de la capacitance de synthèse. Ce réglage est réa lisé en fonction de la bande de fréquence préférentielle selon la formule citée plus haut. Pour ce faire, le circuit de l’inductance de synthèse et/ou celui de la capaci tance de synthèse comprennent par exemple une résistance réglable. Le fait que le circuit électrique résonant 6 soit adaptatif permet de s’adapter encore mieux au pic vibratoire du pare-brise une fois qu’il sera installé sur un véhicule.  The resonant electrical circuit 6 can also be adaptive by adjusting the synthesis inductance and / or the synthesis capacitance. This adjustment is made according to the preferred frequency band according to the formula cited above. To do this, the synthesis inductance circuit and / or that of the synthesis capacitance include, for example, an adjustable resistance. The fact that the resonant electrical circuit 6 is adaptive makes it possible to adapt even better to the vibratory peak of the windshield once it is installed on a vehicle.
Le circuit électrique résonant 6 peut en outre être un circuit multi-résonnant. Cela permet de multiplier les bandes de fréquences sur laquelle on veut atté nuer/supprimer les vibrations localement, en ayant au moins deux pics d’atténua tion. Dans ce cas, le circuit électrique résonant peut par exemple comprendre au moins deux bobines ou deux inductances de synthèse, de préférence reliées deux à deux par une capacitance pour éviter les interférences entre les différentes induc tances. Le circuit électrique multi-résonant comprend de préférence au maximum cinq résonances.  The resonant electrical circuit 6 can also be a multi-resonant circuit. This allows to multiply the frequency bands on which we want to attenuate / suppress vibrations locally, by having at least two attenuation peaks. In this case, the resonant electrical circuit may for example comprise at least two coils or two synthesis inductors, preferably connected two by two by a capacitance to avoid interference between the different inductances. The multi-resonant electrical circuit preferably comprises a maximum of five resonances.
Le circuit électrique résonant 6 est un circuit passif ou semi-passif. En effet, il est passif dans le cas où il ne comporte qu’une ou plusieurs bobines et il est semi- passif dans le cas où il comporte au moins un composant de synthèse. En effet, les composants de synthèse comportent des amplificateurs opérationnels qui, pour fonctionner, ont besoin d’être alimentés par une petite quantité de courant élec trique. Le système de l’invention n’a donc rien à voir avec l’atténuation active. Le transducteur piézoélectrique 5, relié au circuit électrique résonant 6, capte les mou vements locaux du substrat 2, 3 et modifie ces mouvements en réponse, de manière passive ou semi-passive, comme le ferait un système ressort/masse, qui est égale ment un système passif. Comme on n’apporte pas d'énergie dans le système, on ne risque pas d’avoir des instabilités, contrairement à un système de contrôle actif. Le résonateur électromécanique 10 peut comprendre un second transduc teur piézoélectrique qui est situé sur l’autre face du substrat transparent 2, 3, en vis- à-vis du premier transducteur piézoélectrique 5, et qui est relié au même circuit électrique résonant 6 que le premier transducteur piézoélectrique 5. Ainsi, deux transducteurs piézoélectriques voyant la même déformation du substrat 2, 3, puisqu’ils sont au même endroit de ce dernier, sont reliés au même circuit électrique résonant 6. Cela permet d’augmenter l’efficacité du système et d’augmenter la lar geur de la bande de fréquences sur laquelle les vibrations sont à atténuer/supprimer localement. The resonant electrical circuit 6 is a passive or semi-passive circuit. Indeed, it is passive in the case where it comprises only one or more coils and it is semi-passive in the case where it comprises at least one synthetic component. Indeed, the components of synthesis include operational amplifiers which, to function, need to be supplied by a small quantity of electric current. The system of the invention therefore has nothing to do with active attenuation. The piezoelectric transducer 5, connected to the resonant electric circuit 6, captures the local movements of the substrate 2, 3 and modifies these movements in response, passively or semi-passively, as a spring / mass system, which is also a passive system. As we do not bring energy into the system, there is no risk of having instabilities, unlike an active control system. The electromechanical resonator 10 may comprise a second piezoelectric transducer which is situated on the other face of the transparent substrate 2, 3, opposite the first piezoelectric transducer 5, and which is connected to the same resonant electrical circuit 6 as the first piezoelectric transducer 5. Thus, two piezoelectric transducers seeing the same deformation of the substrate 2, 3, since they are in the same place of the latter, are connected to the same resonant electrical circuit 6. This makes it possible to increase the efficiency of the system and to increase the width of the frequency band over which the vibrations are to be attenuated / suppressed locally.
Le transducteur piézoélectrique 5 a par exemple une surface comprise entre 1 et 100 cm2, de préférence entre 30 et 70 cm2 de façon à avoir une amplitude de pic d’atténuation la plus adéquate possible. The piezoelectric transducer 5 has for example a surface of between 1 and 100 cm 2 , preferably between 30 and 70 cm 2 so as to have the most adequate amplitude of attenuation peak possible.
Le transducteur piézoélectrique 5 a par exemple une épaisseur totale com prise entre 1 pm et 2 mm, de préférence entre 500 pm et 1 ,5 mm, voire entre 800 pm et 1 ,2 mm de façon à avoir une amplitude de pic d’atténuation la plus adéquate possible.  The piezoelectric transducer 5 has for example a total thickness comprised between 1 pm and 2 mm, preferably between 500 pm and 1.5 mm, or even between 800 pm and 1.2 mm so as to have an amplitude of attenuation peak as adequate as possible.
Le transducteur piézoélectrique 5 est de préférence transparent et par exemple à base d’oxyde de zinc, ou d’oxyde de titane et de baryum de type BaTi03, ou de nitrure d’aluminium, ou de Titano-Zirconate de Plomb (PZT), ou de polyfluo- rure de vinylidène (PVDF), ou de Titano-Zirconate de Plomb dopé au Lanthane (PLZT), ou encore de copolymère à bloc de poly(styrène-b-isoprène).  The piezoelectric transducer 5 is preferably transparent and for example based on zinc oxide, or on titanium and barium oxide of the BaTiO 3 type, or on aluminum nitride, or on Lead Zirconate (PZT), or of polyvinylidene fluoride (PVDF), or of Titano-Zirconate of Lead doped with Lanthanum (PLZT), or of block copolymer of poly (styrene-b-isoprene).
Le transducteur piézoélectrique 5 comprend un élément piézoélectrique, qui peut par exemple être sous forme de couche mince, situé entre deux électrodes, qui peuvent par exemple être sous forme de couche mince. Au moins une couche diélectrique est de préférence disposée entre chaque électrode et l’élément piézoé lectrique. Les deux électrodes sont de préférence transparentes et de préférence constituées d’un empilement de couches minces comprenant au moins une couche mince en oxyde transparent conducteur, par exemple en oxyde de titane, et/ou une couche mince métallique.  The piezoelectric transducer 5 comprises a piezoelectric element, which can for example be in the form of a thin layer, situated between two electrodes, which can for example be in the form of a thin layer. At least one dielectric layer is preferably disposed between each electrode and the piezoelectric element. The two electrodes are preferably transparent and preferably consist of a stack of thin layers comprising at least one thin layer of transparent conductive oxide, for example titanium oxide, and / or a thin metallic layer.
Chaque première électrode est connectée à un des fils conducteurs ou à une des pistes conductrices 9a, 9b et chaque deuxième électrode est reliée à l’autre fil conducteur ou piste conductrice 9b, 9a.  Each first electrode is connected to one of the conductive wires or to one of the conductive tracks 9a, 9b and each second electrode is connected to the other conductive wire or conductive track 9b, 9a.

Claims

REVENDICATIONS
1 . Pare-brise de véhicule automobile comprenant deux substrats trans parents (2, 3) reliés entre eux par un intercalaire (4) en matériau viscoélastique, au moins un des substrats (2, 3) comprenant à sa surface un résonateur électroméca nique (10) disposé à proximité immédiate d’un emplacement (7) pour une embase d’accessoire tel qu’un rétroviseur intérieur ou une caméra.  1. Motor vehicle windshield comprising two trans parent substrates (2, 3) interconnected by an interlayer (4) of viscoelastic material, at least one of the substrates (2, 3) comprising on its surface an electromechanical resonator (10) disposed in the immediate vicinity of a location (7) for an accessory base such as an interior mirror or a camera.
2. Pare-brise selon la revendication 1 , dans lequel le résonateur électro mécanique (10) comprend un transducteur piézoélectrique (5) et un circuit élec trique résonant (6), reliés entre eux. 2. Windshield according to claim 1, in which the electro-mechanical resonator (10) comprises a piezoelectric transducer (5) and an electrical resonant circuit (6), interconnected.
3. Pare-brise selon la revendication 2, dans lequel le circuit électrique résonant (6) est un circuit passif ou semi-passif comprenant au moins une induc tance, l'inductance étant, soit une bobine, soit une inductance de synthèse. 3. Windshield according to claim 2, in which the resonant electric circuit (6) is a passive or semi-passive circuit comprising at least one inductor, the inductor being either a coil or a synthetic inductor.
4. Pare-brise selon la revendication 3, dans lequel le circuit électrique résonant (6) comprend en outre une capacitance de synthèse négative. 4. Windshield according to claim 3, wherein the resonant electrical circuit (6) further comprises a negative synthesis capacitance.
5. Pare-brise selon la revendication 3 ou 4, dans lequel le circuit élec trique résonant (6) comprend en outre une résistance. 5. Windshield according to claim 3 or 4, wherein the resonant electrical circuit (6) further comprises a resistor.
6. Pare-brise selon l’une des revendications 3 à 5, dans lequel le circuit électrique résonant (6) est en outre adaptatif par réglage de l’inductance et/ou de la capacitance. 6. Windshield according to one of claims 3 to 5, wherein the resonant electrical circuit (6) is further adaptive by adjusting the inductance and / or the capacitance.
7. Pare-brise selon l’une des revendications 2 à 6, dans lequel le circuit électrique résonant (6) est un circuit multi-résonnant. 7. Windshield according to one of claims 2 to 6, in which the resonant electrical circuit (6) is a multi-resonant circuit.
8. Pare-brise selon l’une des revendications 2 à 7, dans lequel le réso nateur électromécanique (10) comprend un second transducteur piézoélectrique qui est situé sur l’autre face du substrat transparent, en vis-à-vis du premier transduc teur piézoélectrique, et qui est relié au même circuit électrique résonant que le pre mier transducteur piézoélectrique. 8. Windshield according to one of claims 2 to 7, in which the electromechanical resonator (10) comprises a second piezoelectric transducer which is located on the other face of the transparent substrate, opposite the first transducer piezoelectric sensor, and which is connected to the same resonant electrical circuit as the first piezoelectric transducer.
9. Pare-brise selon l’une des revendications 2 à 8, dans lequel le trans ducteur piézoélectrique (5) a une surface comprise entre 1 et 100 cm2, de préfé rence entre 30 et 70 cm2. 9. Windshield according to one of claims 2 to 8, in which the piezoelectric transducer (5) has a surface of between 1 and 100 cm 2 , preferably between 30 and 70 cm 2 .
10. Pare-brise selon l’une des revendications 2 à 9, dans lequel le trans ducteur piézoélectrique (5) a une épaisseur totale comprise entre 1 pm et 2 mm, de préférence entre 500 pm et 1 ,5 mm, voire entre 800 pm et 1 ,2 mm. 10. Windshield according to one of claims 2 to 9, in which the piezoelectric transducer (5) has a total thickness of between 1 μm and 2 mm, preferably between 500 μm and 1.5 mm, or even between 800 pm and 1, 2 mm.
1 1 . Pare-brise selon l’une des revendications 2 à 10, dans lequel le trans- ducteur piézoélectrique (5) est transparent et de préférence à base d’oxyde de zinc, ou d’oxyde de titane et de baryum de type BaTiC>3, ou de nitrure d’aluminium, ou de Titano-Zirconate de Plomb (PZT), ou de polyfluorure de vinylidène (PVDF), ou de Titano-Zirconate de Plomb dopé au Lanthane (PLZT), ou encore de copolymère à bloc de poly(styrène-b-isoprène). 1 1. Windshield according to one of Claims 2 to 10, in which the piezoelectric transducer (5) is transparent and preferably based on zinc oxide, or on titanium and barium oxide of BaTiC type> 3 , or aluminum nitride, or lead titano-zirconate (PZT), or polyvinylidene fluoride (PVDF), or titano-lead zirconate doped with lanthanum (PLZT), or of poly block copolymer (styrene-b-isoprene).
12. Pare-brise selon l’une des revendications 2 à 1 1 , dans lequel le trans ducteur piézoélectrique (5) comprend un élément piézoélectrique, par exemple sous forme de couche mince, situé entre deux électrodes, par exemple sous forme de couche mince, au moins une couche diélectrique, par exemple mince, étant de préférence disposée entre chaque électrode et l’élément piézoélectrique. 12. Windshield according to one of claims 2 to 1 1, wherein the piezoelectric transducer (5) comprises a piezoelectric element, for example in the form of a thin layer, located between two electrodes, for example in the form of a thin layer , at least one dielectric layer, for example thin, being preferably disposed between each electrode and the piezoelectric element.
13. Pare-brise selon la revendication 12, dans lequel les deux électrodes sont transparentes et de préférence constituées d’un empilement de couches minces comprenant au moins une couche mince en oxyde transparent conducteur, par exemple en oxyde de titane, et/ou une couche mince métallique. 13. Windshield according to claim 12, in which the two electrodes are transparent and preferably consist of a stack of thin layers comprising at least one thin layer of transparent conductive oxide, for example titanium oxide, and / or a metallic thin layer.
14. Pare-brise selon l’une des revendications 2 à 13, dans lequel le trans- ducteur piézoélectrique (5) est fixé sur une face du substrat (2, 3) qui est en vis-à- vis de l’intercalaire (4). 14. Windshield according to one of claims 2 to 13, in which the piezoelectric transducer (5) is fixed on a face of the substrate (2, 3) which is opposite the interlayer ( 4).
PCT/FR2019/051529 2018-06-28 2019-06-21 Motor vehicle windscreen WO2020002804A1 (en)

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FR1855865A FR3083165A1 (en) 2018-06-28 2018-06-28 MOTOR VEHICLE WINDSHIELD

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP4053924A1 (en) * 2021-03-01 2022-09-07 Saint-Gobain Glass France Metamaterial glazing unit with acoustic insulation properties

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112802442A (en) * 2021-04-15 2021-05-14 上海鹄恩信息科技有限公司 Control method of electrostatic field noise reduction glass, electrostatic field noise reduction glass and storage medium

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1997016817A1 (en) * 1995-11-02 1997-05-09 Trustees Of Boston University Sound and vibration control windows
DE10116166A1 (en) * 2001-03-31 2002-10-10 Daimler Chrysler Ag Active panel, especially vehicle windscreen, has inner panel facing interior elastically joined to outer panel at edges, actuators acting on inner panel to control vibration behavior of inner panel
JP2004232678A (en) * 2003-01-28 2004-08-19 Tokai Rubber Ind Ltd Vibration suppressing method for plate
JP2007040382A (en) * 2005-08-02 2007-02-15 Tokai Rubber Ind Ltd Vibration suppression device

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7551749B2 (en) * 2002-08-23 2009-06-23 Bose Corporation Baffle vibration reducing
EP1413603A1 (en) * 2002-10-25 2004-04-28 Titecs Japan Corporation Vibration-damping material composition
JP2011223473A (en) * 2010-04-13 2011-11-04 Seiko Epson Corp Vibration piece, vibrator, and piezoelectric device
JP2014032137A (en) * 2012-08-06 2014-02-20 Seiko Epson Corp Vibration piece, electronic device and electronic apparatus
CN104536477A (en) * 2014-12-29 2015-04-22 中国电子科技集团公司第二十九研究所 Glass noise active control silencing system and operating method
CN106685258B (en) * 2017-02-28 2018-11-06 江苏大学 It is a kind of using noise and the power generation sound control glass of mechanical oscillation

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1997016817A1 (en) * 1995-11-02 1997-05-09 Trustees Of Boston University Sound and vibration control windows
DE10116166A1 (en) * 2001-03-31 2002-10-10 Daimler Chrysler Ag Active panel, especially vehicle windscreen, has inner panel facing interior elastically joined to outer panel at edges, actuators acting on inner panel to control vibration behavior of inner panel
JP2004232678A (en) * 2003-01-28 2004-08-19 Tokai Rubber Ind Ltd Vibration suppressing method for plate
JP2007040382A (en) * 2005-08-02 2007-02-15 Tokai Rubber Ind Ltd Vibration suppression device

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
JUN LU ET AL: "New Windshield Improves Vehicle Interior Cabin Noise and Articulation Index", JOURNAL OF SOUND AND VIBRATION, 31 December 2003 (2003-12-31), XP055587428, Retrieved from the Internet <URL:https://www.eastman.com/Literature_Center/A/AIAUTO6549.pdf> [retrieved on 20190510] *
MISOL M ET AL: "Experimental investigation of different active noise control concepts applied to a passenger car equipped with an active windshield", JOURNAL OF SOUND AND VIBRATION, ELSEVIER, AMSTERDAM, NL, vol. 331, no. 10, 3 January 2012 (2012-01-03), pages 2209 - 2219, XP028461314, ISSN: 0022-460X, [retrieved on 20120110], DOI: 10.1016/J.JSV.2012.01.001 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP4053924A1 (en) * 2021-03-01 2022-09-07 Saint-Gobain Glass France Metamaterial glazing unit with acoustic insulation properties
WO2022184648A3 (en) * 2021-03-01 2022-10-13 Saint-Gobain Glass France Metamaterial glazing unit with acoustic insulation properties

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