Laminated vehicle glass structure including three-dimensional printed piezoelectric speakers

Abstract

The laminated vehicle glass structure includes a printed piezoelectric actuator for generating sound. An annular piezoelectric actuator is printed on an inner surface of a selected one of the outer glass panel or the inner glass panel. The printing piezoelectric actuator is offset relative to a centerline extending longitudinally between the opposing glass panels. Methods for forming a laminated glass structure including at least one printed piezoelectric actuator are also disclosed. The laminated glass structure may be used anywhere around the vehicle where sound needs to be generated, such as passenger windows, sunroofs, front windshields, rear windshields, and the like. A printed ring piezoelectric actuator is used as a diaphragm to produce sound upon excitation.

Description

Technical Field

[0001] The subject disclosure relates to laminated vehicle glass structures, and more particularly, to laminated vehicle glass structures including a printed piezoelectric speaker for sound generation within the laminated glass structure, wherein the piezoelectric speaker is an annular piezoelectric actuator that is printed on a select glass surface prior to lamination such that the printed piezoelectric speaker is embedded in the laminating material within the laminated glass structure. Background Art

[0002] Current speaker technology used in vehicles typically employs moving coil and cone technology that is selectively placed in doors, dashboards, roofs, and other places throughout the vehicle to produce sound. The speaker acts as a transducer to convert amplified electrical waves from infotainment systems, phones, etc. into sound pressure waves that propagate through the air for the vehicle occupants to hear. The amplifier feeds the signal to two terminals on the back side of the speaker. These terminals pass the current into a cylindrical coil that is suspended in a circular gap between the poles of a permanent magnet. According to Faraday's law, when the current through the coil alternates in one direction with the applied signal, the coil moves back and forth within the magnetic field. The center of the speaker cone is attached to one end, which is driven back and forth by the moving coil. The cone is held at its edges by an airtight suspension or surround. As the cone moves, it pushes and pulls the surrounding air; by doing so, it creates pressure waves in the air in the form of sound.

[0003] Coil and cone speakers add considerable weight to the vehicle, require separate mounts and connections, take up valuable interior trim space, allow significant road noise intrusion, and are subject to considerable impact and environmental abuse. In addition, due to the limited trim space available for speaker placement, the speakers can be poorly positioned for listening. Their on-axis radiation is typically directed low in the vehicle toward the legs and midsection of seated occupants rather than at the occupants' ears. As a result, the direct sound from the speaker to the listener is typically far off axis, and the frequency response is highly variable, typically with insufficient high frequencies. In the high noise environment of the vehicle, this typically results in a loss of mid- and high-frequency audio information. "Imaging," the perception of where the sound is coming from, is also adversely affected because the speakers are typically mounted low in the vehicle; for the front passengers, the audio image is pulled down into the doors, while rear passengers have an image to the side or rear, rather than the image that should be presented in front of them.

[0004] Therefore, it is desirable to better position speakers within a vehicle while minimizing trim space requirements, weight, road intrusion noise, pollution, etc. Summary of the invention

[0005] In an exemplary embodiment, a laminated glass structure for a vehicle includes an outer glass panel, an inner glass panel, and a laminated material therebetween. The outer glass panel includes an outer surface facing the vehicle surroundings and an inner surface. The inner glass panel includes an outer surface facing the vehicle interior and an inner surface. The laminated material is located between the outer glass panel and the inner glass panel and is bonded to the inner surfaces of the outer glass panel and the inner glass panel. The laminated glass structure further includes at least one printed annular piezoelectric actuator on a frit material, wherein at least one printed annular piezoelectric actuator and the frit material are embedded in the laminated material and offset relative to a centerline extending longitudinally between the first glass panel and the second glass panel. In one or more aspects, at least one printed annular piezoelectric actuator is printed on the inner surface of the outer glass panel. In other aspects, at least one printed annular piezoelectric actuator is printed on the inner surface of the inner glass panel. In other aspects, at least one of the printed annular piezoelectric actuators is printed on the inner surface of the inner glass panel and printed on the inner surface of the outer glass panel.

[0006] At least one printed annular piezoelectric actuator may include a first conductive layer on a glass material, a piezoelectric material on the first conductive layer, and a second conductive layer on the piezoelectric material, wherein at least one printed annular piezoelectric actuator has an elliptical, circular, and / or polygonal shape. In one or more aspects, the laminated material includes polyvinyl butyral resin or ethylene vinyl acetate. In one or more embodiments, the laminated glass structure also includes a plastic layer, which is configured to provide solar reflectivity within the laminated material and between the inner glass panel and the outer glass panel. In one or more aspects, the outer glass panel has a thickness in the range of about 1.6 mm to about 3.5 mm, the inner glass panel has a thickness in the range of about 0.7 mm to about 3.5 mm, the laminated material has a thickness in the range of about 0.3 mm to about 2.0 mm, and at least one printed annular piezoelectric actuator has a thickness less than the laminated material. The glass material has a width greater than the width of the printed annular piezoelectric actuator and can be printed onto a selected inner glass surface. The glass material can be translucent. In one or more aspects, the piezoelectric material can be lead zirconium titanate.

[0007] In another exemplary embodiment, a method of forming a laminated glass structure for a vehicle includes printing an annular pattern of glass frit material on an inner surface of a selected glass panel. Then a first conductive layer is printed onto the annular pattern of glass frit material. A piezoelectric material is printed onto the first conductive layer, and a second conductive layer is printed onto the piezoelectric material to form a piezoelectric actuator. A selected glass panel, a laminated material sheet; and another glass panel stacked arrangement, wherein the inner surface of the selected glass panel contacts the laminated material sheet, and the other glass panel includes an inner surface that contacts the laminated material sheet so that the laminated material sheet is sandwiched therebetween. Heat and pressure are applied to laminate the selected glass panel to another glass panel, wherein the piezoelectric actuator on the annular pattern of glass frit material has a height dimension that is less than the thickness of the laminated material sheet. The laminated material sheet may include polyvinyl butyral resin or ethylene vinyl acetate. In one or more aspects, printing the glass frit material, the first conductive layer and the second conductive layer, and the piezoelectric material includes robotically depositing droplets of the glass frit material, the first conductive layer and the second conductive layer, and the piezoelectric material to form the piezoelectric actuator. In other aspects, printing the glass material, the first conductive layer and the second conductive layer, and the piezoelectric material comprises inkjet printing, screen printing, additive manufacturing, etching, or a combination comprising at least one thereof. Printing the piezoelectric material may comprise lead zirconium titanate, wherein the annular pattern may comprise a circle, an ellipse, or a polygon.

[0008] In another exemplary embodiment, a laminated glass structure for a vehicle includes an outer glass panel, an inner glass panel, and a laminated material therebetween. The outer glass panel has a thickness of about 1.6 mm to about 3.5 mm, and includes an outer surface and an inner surface exposed to the vehicle's surroundings. The inner glass panel has a thickness of about 0.7 mm to about 3.5 mm, and includes an inner surface and an outer surface exposed to the vehicle's interior. The laminated material has a thickness of about 0.3 mm to about 2 mm between the outer glass panel and the inner glass panel, and contacts the inner surfaces of the outer glass panel and the inner glass panel. The laminated material is polyvinyl butyral resin or ethylene vinyl acetate. The printed piezoelectric actuator has a thickness less than the thickness of the laminated material and is in the shape of a ring having a thickness less than the actual thickness of the laminated material. The printed piezoelectric actuator is disposed on a selected inner glass surface and is offset relative to a centerline extending between the inner surfaces of the outer glass panel and the inner glass panel, and contacts one of the inner surfaces of the outer glass panel or the inner glass panel, and the laminated glass structure forms a fixed glass roof system, a movable glass roof system, a front windshield, a rear quarter glass, a side movable glass and / or a non-removable side glass.

[0009] The above features and advantages and other features and advantages of the present disclosure are apparent from the following detailed description when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Other features, advantages and details appear, by way of example only, in the following detailed description, which refers to the accompanying drawings, in which:

[0011] Figure 1 is a top view of a ring-shaped piezoelectric actuator provided within a laminated glass structure according to one or more embodiments of the present disclosure;

[0012] Figure 2 According to one or more embodiments of the present disclosure, Figure 1 An enlarged cross-sectional view taken along line AA of FIG. 1 showing various printed layers defining an annular piezoelectric actuator embedded within a laminated glass structure;

[0013] Figure 3 is a cross-sectional view of a laminated glass structure including an annular piezoelectric actuator printed on an inner surface of an outer glass panel of the laminated glass structure according to one or more embodiments of the present disclosure; and

[0014] Figure 4 is a cross-sectional view of a laminated glass structure including an annular piezoelectric actuator printed on an outer surface of an inner glass panel of the laminated glass structure according to one or more embodiments of the present disclosure. DETAILED DESCRIPTION

[0015] The following description is merely exemplary in nature and is not intended to limit the present disclosure, its application, or uses.

[0016] According to an exemplary embodiment, a laminated glass structure for a vehicle is provided and includes one or more printed piezoelectric actuators within the laminated glass structure, and the one or more printed piezoelectric actuators can be printed as a three-dimensional structure on a selected inner glass surface corresponding to an outer or inner glass panel within the laminated glass structure. For example, regulated power can be supplied to the piezoelectric actuator via a vehicle infotainment system. In one or more embodiments, the infotainment amplifier system can be electrically connected to the piezoelectric actuator using a patterned conductive coating directly disposed on a selected inner glass surface within the laminated glass structure and / or by using a negative wire and a positive wire electrically connected to the piezoelectric actuator, which may or may not be insulated if sufficiently spaced from each other. In the case of patterned wires within the laminated structure, the conductive surface can be applied first and then patterned on a selected inner surface of the glass panel or on a selected surface of a plastic layer (if present) within the laminate.

[0017] Although reference will be made throughout this application to two glass panels defining a laminated glass structure, it should be apparent that more than two glass panels may be used, although the increase in weight would make it less practical. Laminated glass structures including one or more embedded piezoelectric actuators according to the present disclosure may be used in vehicles utilizing laminated glass components, including, for example, fixed glass roof systems, front windshields, side sliding glass, rear side panel glass, rear glass, etc. Unlike coil and cone based speakers, piezoelectric actuators advantageously occupy minimal space, have significantly lower weight, can be used to occupy space within a vehicle that was not previously used for speaker placement (i.e., in a laminated glass structure), and, in contrast to coil and cone speakers, which are typically placed within a decorative panel (e.g., a door panel) below the vehicle window, the piezoelectric actuators may be located above and / or beside the occupants.

[0018] A piezoelectric actuator is generally a transducer device that converts electrical energy into mechanical displacement or stress, or vice versa, based on the piezoelectric effect. The piezoelectric effect is defined as the ability of some materials to change their shape or size in response to an applied electric field. In the present disclosure, the printed piezoelectric actuator has a ring shape and can convert electrical energy into vibrations, thereby typically acting as a diaphragm to produce sound in a manner similar to a coil and cone speaker.

[0019] The method for printing a piezoelectric actuator generally includes printing a desired pattern of a (glass or ceramic) glass material, which may be opaque or translucent, depending on the glass material composition; printing a conductive layer onto the patterned glass material, and printing a paste of a powdered piezoelectric material onto the patterned conductive layer to form a piezoelectric ceramic layer. The specific printing method is not intended to be limited and may include screen printing, inkjet printing, etching, aerosol jet printing, 3D printing, droplet printing, selective laser sintering, free extrusion molding, stereolithography, digital light processing, laminated object manufacturing, etc. The method may also include robotic inkjet deposition of various materials and layers defining the printed piezoelectric actuator. For example, the method may include robotic deposition of droplets of about 80 microns to about 100 microns in size of each of a non-conductive glass material, a conductive paste, and a piezoelectric material, wherein the annular geometry may be adjusted to provide the desired sound quality, geometry, aesthetics, durability, transparency, quality, etc.

[0020] The laminated glass structure includes a first glass panel and a second glass panel (including a printed piezoelectric actuator on a selected inner surface thereof) and one or more laminated material sheets, one or more laminated material sheets are stacked and arranged so that the laminated material is located between the first glass panel and the second glass panel. The selected inner glass surface of these panels includes one or more of the three-dimensional printed piezoelectric actuators, which are configured to contact the laminated material sheets during assembly. The assembly is then subjected to heat and pressure to cohesively combine the first glass panel and the second glass panel and form a laminated glass assembly. In this way, the three-dimensionally printed piezoelectric actuator is contacted with one of the inner glass surfaces and embedded in the laminated material. In addition, because the piezoelectric actuator is printed on a selected one of the inner glass surfaces of the first glass panel or the second glass panel, the subsequent lamination causes the three-dimensionally printed piezoelectric actuator to be offset relative to the centerline extending longitudinally between the first glass panel and the second glass panel, which produces the maximum sound output.

[0021] As previously described, laminated glass assemblies including printed piezoelectric actuators can be used in vehicles that use laminated glass assemblies, including, for example, glass roofs, front and rear windshields, passenger windows, etc. Unlike coil and cone based speakers, printed piezoelectric actuators advantageously occupy minimal space, can have any printed pattern and configuration including decorative designs, can be formed from translucent materials, are lightweight, can be used to occupy space within a vehicle that was previously not used for speaker placement (i.e., within a laminated glass structure), and can be located above and / or beside occupants within the glass laminate, as opposed to coil and cone speakers, which are typically placed within a decorative panel (e.g., a door panel) below the window or occupy valuable roof space. This can limit the size of the laminated glass roof panel because conventional cone and coil based speakers are not attached to the glass.

[0022] Conventional techniques associated with the laminated glass manufacturing process for a vehicle may or may not be described in detail herein. In addition, the various tasks and process steps described herein may be incorporated into a more comprehensive program or process having additional steps or functions not described in detail herein. In particular, the various steps in the windshield manufacturing process are well known, and therefore, for the sake of brevity, many conventional steps will only be briefly mentioned herein or will be omitted entirely without providing well-known process details.

[0023] For ease of description, spatially relative terms such as "below," "beneath," "lower," "above," "upper," etc. may be used herein to describe the relationship of one element or feature to another element or features as shown. It should be understood that, in addition to the orientations shown in the figures, spatially relative terms are intended to cover different orientations of the device in use or operation. For example, if the device in the drawings is flipped, an element described as being "below" or "below" other elements or features will be oriented to be "above" the other elements or features. Thus, the term "below" can cover both orientations of above and below. The device may be oriented in other ways (rotated 90 degrees or in other orientations), and the spatially relative descriptors used herein are interpreted accordingly.

[0024] The following definitions and abbreviations are used to interpret the claims and specification. As used herein, the terms "comprises," "comprising," "includes," "including," "has," "having," "contains," or "containing," or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a composition, mixture, process, method, article, or apparatus that includes a list of elements is not necessarily limited to only those elements, but may include other elements not expressly listed or inherent to such composition, mixture, process, method, article, or apparatus.

[0025] The terms "one" and "an" do not indicate a limitation of quantity, but rather indicate the presence of at least one of the referenced items. Unless the context clearly indicates otherwise, the term "or" means "and / or". References to "aspects" throughout the specification mean that specific elements (e.g., features, structures, steps, or characteristics) described in conjunction with the aspect are included in at least one aspect described herein, and may or may not exist in other aspects. In addition, it should be understood that the described elements may be combined in any suitable manner in various aspects. In addition, the terms "upper", "lower", "top", "bottom", "left", and "right" and their derivatives shall relate to the described structures as they are oriented in the accompanying drawings. The same figure numbers in the various figures may refer to the same structural components or portions thereof.

[0026] When an element such as a layer, film, region, or substrate is referred to as being "on" another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements present.

[0027] Unless stated to the contrary herein, all test standards are the most current standards in effect as of the filing date of this application or, if priority is claimed, the filing date of the earliest priority application in which the test standards appear.

[0028] Unless defined otherwise, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0029] As mentioned above, glass panels for vehicles are generally laminated glass structures, which include an outer glass panel and an inner glass panel laminated together using one or more sheets of polymer laminate material. The laminated structure can be used as a front windshield, rear glass, fixed glass roof system, movable glass roof system, side sliding glass, rear side panel glass, movable and static passenger windows, etc.

[0030] Laminated glass structures are typically formed of curved or flat glass panels having a shape intended for their end use. For example, car roof applications typically utilize rectangular flat or curved glass panels laminated together. Known glass panels can be made of heat ray absorbing glass, conventional clear glass, green glass, or UV green glass. In some embodiments, adjustments can be made so that the outer glass panel ensures the desired solar energy and / or tint absorptivity and the inner glass panel provides visible light transmittance. In addition, additional sheets within the laminated glass structure can also be used to provide certain features. For example, a plastic layer can be used within the laminated structure to provide solar reflectivity.

[0031] Although there is no particular limitation on the thickness of the laminated glass structure, for roof applications, the total thickness of the outer glass panels is generally set at about 1.6 to about 3.5 millimeters (mm), and the inner glass panels are generally set at about 0.7 to about 3.5 mm. The laminate can have a thickness in the range of about 0.3 mm to about 2 mm, but greater or lesser thicknesses can be used. In one or more embodiments, the thickness of the laminate is about 0.76 mm.

[0032] The process of laminating the laminated glass structure generally includes applying heat and pressure to bond two or more layers of glass together with a layer of laminating material (e.g., polyvinyl butyral, ethylene vinyl acetate, or the like) between them. The laminating material is generally melted and / or softened by heating, allowing it to bond the opposing layers of glass together and produce a strong, durable laminated structure. The temperature range for laminating glass is generally between 120°C and 150°C (248°F and 302°F), but some processes can use higher or lower temperatures, depending on the materials and equipment used. The pressure range for laminating glass can vary widely depending on the specific lamination process, but is generally between 10 and 15 psi (0.7 to 1 bar). Some processes can use higher pressures to achieve a stronger bond, while other processes can use lower pressures to reduce the risk of damaging the glass. In some applications, a mask layer (i.e., a frit layer) can be formed of ceramic, metal, etc. and can be provided around the periphery of one or two glass panels before lamination.

[0033] In one or more embodiments, a laminated glass structure for a vehicle includes a printed piezoelectric actuator disposed within a polymer laminate for laminating a first glass panel to a second glass panel. The printed piezoelectric actuator is configured to be asymmetrically disposed within the thickness of the polymer laminate relative to the distance from the outer glass panel and the inner glass panel. It has been found that if the piezoelectric actuator has the same thickness as the polymer laminate and contacts the inner surface of each glass panel, the vibrations are in opposite phases and cancel each other out, thereby generating no sound. Similarly, if the piezoelectric actuator is located in the middle of the polymer laminate (i.e., equidistant from the opposing inner glass surfaces), no sound will be generated. For example, a laminated glass structure will not generate sound, the laminated glass structure comprising two polymer laminate sheets of the same thickness and a piezoelectric actuator that is printed onto one of the sheet surfaces without contacting the inner surface of the glass panel facing the outside or the inner surface of the inner glass panel and at the same distance from each corresponding inner surface of the glass panel. The vibrations from the piezoelectric actuators of each respective glass panel will be in opposite phases and cancel each other out so that no sound is produced. However, if the piezoelectric actuator is configured to have a thickness less than that of the polymer laminate so that it is at least partially embedded in and in contact with or closer to the inner surface of the outer glass panel or the inner glass panel, the vibrations from the selected inner surface of the outer glass panel or the inner glass panel will have the same phase and provide sound.

[0034] The process for printing annular piezoelectric actuators generally comprises printing a frit pattern in an annular pattern onto a selected inner surface of an outer or inner glass panel in a laminated glass structure. Reference to an "inner surface" generally refers to the surface of the respective glass panel that contacts the laminating material when the outer glass panel, laminating material, and inner panel are stacked and subsequently subjected to heat and pressure to form the laminated glass structure. The annular pattern of the frit material can be formed during the application of the mask material or after the deposition of the mask material and subsequent etching process to form the pattern.

[0035] A first conductive layer of the conductive paste is deposited onto the annular pattern of the frit material, the annular pattern having a width that is generally smaller than the pattern width provided for the frit material.

[0036] A piezoelectric material, such as lead zirconium titanate, is deposited on the first conductive layer.

[0037] A second conductive layer of a conductive paste is deposited onto the piezoelectric material, which may be the same or different than the first conductive paste. The deposited individual layers of the piezoelectric actuator may be annealed and sintered prior to or during a subsequent lamination process.

[0038] Exemplary glass frit materials include a molten, quenched and granulated ceramic composite of a calcined mixture of sand and flux. It is deposited on the windshield in dots by digital deposition, screen printing, chemical vapor deposition, physical vapor deposition, etc. to produce varying degrees of opacity or translucency. The ceramic composite can be applied as a glass flux and fired at about 550°C, with a typical composition of 60-85% Bi, B, Zn, Si oxides, 15-40% stain with oxides of Cu, Co, Fe, Ni, Mn, Cr, and 0-15% additives of oxides, sulfides, metal compounds and silicates. The thickness of the deposited ceramic composite is typically in the range of about 0.03 to 0.25 mm, depending on the distribution and number of passes used to form the patterned glass frit material.

[0039] Exemplary conductive pastes include conductive metals such as palladium, silver, silver palladium, platinum, gold, etc. In addition, the paste may include a spreading agent commonly known in the art. The thickness of the deposited conductive paste layer is typically in the range of about 5 microns to about 30 microns.

[0040] The piezoelectric material may be lead zirconium titanate, calcium titanate, barium titanate, lead titanate, strontium titanate, etc. The thickness of the deposited piezoelectric material is typically in the range of about 5 microns to about 30 microns, as desired.

[0041] Figure 1is a top view of an assembly 50 including a laminated glass structure 52 having a circular piezoelectric actuator 54 printed onto one of the inner glass surfaces between opposing glass panels according to one or more embodiments of the present disclosure. The printed piezoelectric actuator 54 is not intended to be limited to a circular shape and may be any annular shape. For example, the annular three-dimensional printed piezoelectric actuator may be patterned as an ellipse; a polygon, such as a hexagon; an irregular annular shape, etc., which may be repeated at various locations on the inner glass surface. The repeating pattern is not intended to be limited and may include a variety of different shapes or the same shape repeated throughout the laminated glass structure. Printing the piezoelectric actuator on the glass surface may be accomplished in an offline process after or during the manufacture of the laminated glass structure, which advantageously eliminates the need to mount a traditional cone and coil speaker system on the outside of the laminated glass structure, thereby improving the process efficiency of manufacturing the vehicle.

[0042] Now go to Figure 2 , depicting along Figure 1 AA of the laminated glass structure assembly 50. The laminated glass structure assembly 50 includes a first glass panel 60 and a second glass panel 62, respectively, and a laminating material 65 located between the first glass panel 60 and the second glass panel 62, for bonding the first glass panel 60 and the second glass panel 62 together, respectively. The first glass panel 60 includes an outer surface 64 and an inner surface 58. The second glass panel 62 also includes an outer surface 66 and an inner surface 68. The annular piezoelectric actuator 54 is formed on a glass material layer 56, which is deposited on a selected inner surface of the glass panel (e.g., the inner surface 58 of the first glass panel 60 as shown). The glass material layer 56 can be deposited and patterned to have a shape similar to the annular piezoelectric actuator 54, or can be a continuous layer. Typically, the width of the annular piezoelectric actuator 54 is less than the width of the glass material layer 56. The glass material layer 56 can be a glass or ceramic material, and is selected to be opaque or translucent according to the composition. Forming the piezoelectric actuator 54 includes depositing a first conductive paste layer 70 in a desired annular shape onto the patterned frit layer 56. A piezoelectric material 72 is then printed on the first conductive paste layer 70, followed by depositing a second conductive paste layer 74 on the printed piezoelectric material 72 to form the piezoelectric actuator 54. As previously described, the various layers may be robotically deposited onto selected interior surfaces of a glass panel (e.g., the interior surface 58 of the first glass panel 60 as shown).

[0043] As shown, piezoelectric actuator 54 has a thickness less than laminate 65 and is off-axis relative to the longitudinal centerline between opposing first and second glass panels 60, 62, respectively. Additionally, piezoelectric actuator 54 is configured such that frit layer 56 is wider than the width dimension of piezoelectric actuator 54.

[0044] Depending on the type of piezoelectric material and the desired shape and size of the piezoelectric actuator, there are many non-limiting methods to print piezoelectric materials onto glass or ceramic substrates. For example, inkjet printing can be used to deposit droplets of piezoelectric ink (e.g., PVDF-TrFE) onto a substrate including a conductive electrode using an inkjet printer to form a piezoelectric actuator. The ink is then sintered and tempered to form a piezoelectric layer. In another example, a three-dimensional (3-D) printer can be used to manufacture an annular piezoelectric actuator layer by layer. The piezoelectric material used in the piezoelectric actuator can be a polymer, ceramic, or composite material. 3-D printing can be accomplished by polarizing the piezoelectric material before, during, or after the printing process. Polarization is the process of applying an electric field to align the electric dipoles in the piezoelectric material and enhance their piezoelectric effect. In other examples, a screen printer can be used to deposit a layer of piezoelectric slurry (such as lead zirconium titanate) onto a substrate together with an electrode (i.e., a conductive layer). The slurry is then fired to form a piezoelectric actuator.

[0045] Now turn to Figure 3 , depicting a cross-sectional view of a laminated glass structure 100 according to one or more embodiments of the present disclosure. The laminated glass structure 100 includes a first glass panel 102, a second glass panel 104, a lamination layer 106 intermediate the first glass panel 102 and the second glass panel 104, respectively, and an annular piezoelectric actuator 108 disposed on an inner surface 110 of the first glass panel 102. When the first and second glass panels 102, 104, and the lamination layer 106 are exposed to heat and pressure to form the laminated glass structure 100, the piezoelectric actuator 108 is printed onto the inner surface 110 of the first glass panel 102 at a desired location on a glass frit material (not shown) as generally described in the previous embodiments, and is embedded within the lamination layer 106. The first glass panel 102 also includes an outer surface 112 that faces the external environment when in use. The second glass panel 104 includes an outer surface 114 and an inner surface 116 that face the interior of the vehicle. The electrical signal provided to the piezoelectric actuator 108 can be used to generate sound from the laminated glass structure and into the interior of the vehicle. For example, the laminated glass structure 100 may be used as a vehicle roof panel (fixed or movable) and may include a plurality of piezoelectric actuators 108 spaced around the panel in a decorative pattern to provide sound directly above the vehicle occupants without impacting the decorative panel space.

[0046] exist Figure 4, a cross-sectional view of a laminated glass structure 200 according to one or more embodiments of the present disclosure is depicted. The laminated glass structure 200 includes a first glass panel 202, a second glass panel 204, a laminating layer 206 intermediate the first glass panel 202 and the second glass panel 204, respectively, and a piezoelectric actuator 208 disposed on an inner surface 210 of the second glass panel 204. The second glass panel 204 also includes an outer surface 212 facing the interior of the vehicle. The annular piezoelectric actuator 208 is printed to the inner surface 210 of the second glass panel 204 at a desired location on a glass frit material (not shown), and is embedded within the laminated glass structure 200 when the first and second glass panels 202, 204, and the laminating layer 206 are exposed to heat and pressure, respectively. The first glass panel 202 also includes an outer surface 214 facing the external environment when in use, and an inner surface 216. The electrical signal provided to the piezoelectric actuator 208 can be used to generate sound from the laminated glass structure 200 and into the interior of the vehicle.

[0047] In the above embodiments, when annular piezoelectric actuators are utilized within a laminated glass structure, the piezoelectric actuators may be printed at the same plane (i.e., on a patterned frit material deposited onto the same interior surface of an outer glass panel or an inner glass panel and substantially offset relative to a centerline extending longitudinally between the first glass panel and the second glass panel).

[0048] Although the above disclosure has been described with reference to exemplary embodiments, it will be appreciated by those skilled in the art that various changes may be made and equivalents may be substituted for its elements without departing from its scope. In addition, many modifications may be made to adapt specific circumstances or materials to the teachings of the disclosure without departing from the basic scope of the disclosure. Therefore, it is intended that the disclosure is not limited to the specific embodiments disclosed, but will include all embodiments falling within its scope.

Claims

1. A laminated glass structure for a vehicle, comprising: an outer glass panel including an inner surface and an outer surface facing the environment surrounding the vehicle; an inner glass panel including an inner surface and an outer surface facing an interior of the vehicle; a laminate material disposed between the outer glass panel and the inner glass panel and bonded to inner surfaces of the outer glass panel and the inner glass panel; as well as and at least one printed annular piezoelectric actuator on a frit material formed on a selected one of the inner surfaces, wherein the at least one printed annular piezoelectric actuator and the frit material are embedded within the laminate and offset relative to a centerline extending longitudinally between the outer glass panel and the inner glass panel.

2. The laminated glass structure of claim 1, wherein at least one printed annular piezoelectric actuator is printed on an inner surface of the outer glass panel.

3. The laminated glass structure of claim 1, wherein at least one printed annular piezoelectric actuator is printed on an inner surface of the inner glass panel.

4. The laminated glass structure of claim 1, wherein at least one printed annular piezoelectric actuator has an elliptical shape, a circular shape, and / or a polygonal shape.

5. The laminated glass structure of claim 1, further comprising a plastic layer configured to provide solar reflectivity within the laminate and intermediate the inner glass panel and the outer glass panel.

6. The laminated glass structure of claim 1, wherein the frit material has a width greater than a width of the printed annular piezoelectric actuator.

7. A method of forming a laminated glass structure for a vehicle, comprising: printing an annular pattern of frit material on an inner surface of a selected glass panel; printing a first conductive layer onto the annular pattern of the annular pattern of frit material; printing a piezoelectric material onto the first conductive layer; printing a second conductive layer onto the piezoelectric material to form a piezoelectric actuator; Arranging the selected glass panels, laminate sheets in a stack; and another glass panel, wherein an inner surface of the selected glass panel contacts the sheet of laminate material, and the other glass panel includes an inner surface that contacts the sheet of laminate material such that the sheet of laminate material is sandwiched therebetween; as well as Heat and pressure are applied to laminate the selected glass panel to the other glass panel, wherein the piezoelectric actuators on the annular pattern of frit material have a height dimension that is less than the thickness of the laminate material sheet.

8. The method of claim 7, wherein printing the frit material, first and second conductive layers, and the piezoelectric material comprises robotically depositing droplets of the frit material, first and second conductive layers, and the piezoelectric material to form the piezoelectric actuator.

9. The method of claim 7, wherein printing the frit material, the first and second conductive layers, and the piezoelectric material comprises inkjet printing, screen printing, additive manufacturing, etching, or a combination comprising at least one thereof.

10. The method of claim 7, wherein the annular pattern comprises a circular shape, an elliptical shape, or a polygonal shape.

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