In various embodiments, the present disclosure relates generally to apparatuses, systems, and methods for incorporating thin film electroactive polymer devices. More specifically, the present disclosure relates to a frameless actuator module for moving and/or vibrating surfaces and components of a device. In particular, the present disclosure relates to a frameless haptic feedback module that can be integrated with a device for moving and/or vibrating surfaces and components of the device.
Some hand held devices and gaming controllers employ conventional haptic feedback devices using small vibrators to enhance the user's gaming experience by providing force feedback vibration to the user while playing video games. A game that supports a particular vibrator can cause the device or gaming controller to vibrate in select situations, such as when firing a weapon or receiving damage to enhance the user's gaming experience. While such vibrators are adequate for delivering the sensation of large engines and explosions, they are quite monotonic and require a relatively high minimum output threshold. Accordingly, conventional vibrators cannot adequately reproduce finer vibrations or non-periodic motions that evoke specific haptic effects such as button clicks. Besides low vibration response bandwidth, additional limitations of conventional haptic feedback devices include bulkiness and heaviness when attached to a device such as a smartphone or gaming controller.
To overcome these and other challenges experienced with conventional haptic feedback devices, the present disclosure provides Electroactive Polymer Artificial Muscle (EPAM™) based frameless actuator modules comprising dielectric elastomers that have the bandwidth and the energy density required to make frameless haptic devices that are both responsive and compact. These frameless actuator modules may find use in a variety of applications, and are not limited to haptic feedback. Such EPAM™ based frameless haptic feedback modules comprise a thin sheet, which comprises a dielectric elastomer film sandwiched between two electrode layers. When a high voltage is applied to the electrodes, the two attracting electrodes compress the film thickness in the energized area. The EPAM™ based frameless actuator device provides a slim, low-powered actuator module that can be placed underneath an inertial mass (usually a battery or a touch surface) on a movable suspension to generate haptic feedback that can be perceived by the user.
In one embodiment, a frameless actuator is provided. The frameless actuator comprises a frameless actuator comprising at least one elastomeric dielectric film disposed between first and second electrodes. A first pressure sensitive adhesive is applied on one side of the frameless actuator film. A second pressure sensitive adhesive is applied on an opposite side of the frameless actuator film.
The present invention will now be described for purposes of illustration and not limitation in conjunction with the figures, wherein:
Before explaining the disclosed embodiments in detail, it should be noted that the disclosed embodiments are not limited in application or use to the details of construction and arrangement of parts illustrated in the accompanying drawings and description. The disclosed embodiments may be implemented or incorporated in other embodiments, variations and modifications, and may be practiced or carried out in various ways. Further, unless otherwise indicated, the terms and expressions employed herein have been chosen for the purpose of describing the illustrative embodiments for the convenience of the reader and are not for the purpose of limitation thereof. Further, it should be understood that any one or more of the disclosed embodiments, expressions of embodiments, and examples can be combined with any one or more of the other disclosed embodiments, expressions of embodiments, and examples, without limitation. Thus, the combination of an element disclosed in one embodiment and an element disclosed in another embodiment is considered to be within the scope of the present disclosure and appended claims.
The present disclosure provides various embodiments of Electroactive Polymer Artificial Muscles (EPAM™) based frameless devices. Before launching into a description of various devices comprising EPAM™ based frameless actuator modules, the present disclosure briefly turns to
Advantages of the EPAM™ based actuator module 10 include providing force feedback sensations to the user that are more realistic feelings, can be felt substantially immediately, consume significantly less battery life, and are suited for customizable design and performance options. The actuator module 100 is representative of actuator modules developed by Artificial Muscle Inc. (AMI), of Sunnyvale, Calif.
Still with reference to
Additional disclosure of haptic feedback modules integrated with the device for moving and/or vibrating surfaces and components of a device are described in commonly assigned and concurrently filed International PCT Patent Application No. PCT/US2012/______, filed on an even date herewith, entitled “FLEXURE APPARATUS, SYSTEM, AND METHOD,” the entire disclosure of which is hereby incorporated by reference.
Various embodiments of frameless actuator modules are described in the present disclosure.
In one embodiment, at process 516, the first release liner 402 is removed from the actuator 400A to provide actuator 400B, which is attached, e.g., adhered, to the bottom plate 502 by way of the pressure sensitive adhesive 416. Thus, the actuator 400B is fixedly coupled to the bottom plate 502.
Once the actuator 400B is fixedly coupled to the bottom plate 502, in one embodiment, at process 518 the second release liner 404 is removed from the actuator 400B to provide actuator 400C, which is attached, e.g., adhered, to the top plate 504. It is noted that the removable pressure sensitive adhesive 512 remains attached to the second release liner 404 when it is removed by proper selection of release energy, as discussed below. The actuator 400C now comprises the first dielectric film 506 adhesively attached to the bottom plate 502 and the second dielectric film 508 adhesively attached to the top plate 504. As previously discussed, the first and second dielectric films 506, 508 are adhesively coupled by way of the film-to-film adhesive 510. The release layer 514 remains attached to the one side of the second dielectric film 508 opposite an inner wall portion of the top plate 504.
It will be appreciated that the release energies of the various pressure sensitive adhesives, removable pressure sensitive adhesives, first and second release liners, and release layer is selected as follows, in accordance with one embodiment. The release energy of the pressure sensitive adhesive 416/first release liner 402 interface is less than the release energy of the removable pressure sensitive adhesive 512/release layer 514 interface, which is less than the release energy of the second release liner 404/pressure sensitive adhesive 414 interface, which has approximately the same release energy as the second release liner 404/removable pressure sensitive adhesive 512 interface. TABLE 1 provides release energy data for various combinations of release surface and adhesive interfaces. TABLE 2 provides peel force data for various combinations of substrates and adhesive interfaces.
The singulated laminated actuator film structure can now be attached to a device. To attach the singulated laminated actuator film structure, the bottom release liner is removed 622 and attached 624 on top of the device. The top release liner is removed 626 and the at least one via can be filled 628.
TABLE 3 provides performance data for a 3-bar frameless actuator.
Those skilled in the art will appreciate that frameless actuator configurations as described herein provide a variety of benefits and advantages relative to framed actuator configurations. Such advantages include decrease in the overall thickness of the actuator module. For example, a two layer (2L) frameless actuator may be realized with a two-layer thickness of about 175 μm to about 215 μm and an overall thickness of about 500 μm for a actuator module. For example, a four layer (4L) frameless actuator may be realized with a four-layer thickness of about 275 μm to about 315 μm and an overall thickness of about 700 μm for a actuator module. By comparison, the thickness of framed actuators and modules would be about 500 to 600 μm and about 0.9 to 1.1 mm, respectively. In addition, the frameless actuator designs can potentially decrease material and manufacturing costs for die-cut pressure sensitive adhesives applied manually. Frameless actuators can be formed by non-contact printing and can be transparent with transparent electrodes and buss bars. Additional advantages of frameless actuators, as shown in
Furthermore, in other embodiments, an actuator module without a frame is provided to reduce the overall thickness. The actuator module comprises a frame (or liner) that is completely disposable. For example, if the adhesive is printed in the pattern of the output bars on one side of the actuator film and in the pattern of the frame on the other side of the actuator film, the film may be attached to a surface of a fixed substrate in a device, e.g., the back of a backlight and a housing of the unit, and finally cut away the disposable frame. In one embodiment, the method comprises pre-stretching or pre-straining the actuator film; printing windows in a ripstop or joining the actuator film to a temporary “frame” material strong enough to support the pre-strain after singulation; printing electrodes and bus bars; printing adhesive as described above; adding release liners; and singulating the actuators.
For single layer devices, the perimeter of the actuator film could be fully adhered to one of the rigid surfaces of a substrate. For multiple layers, a stronger film-to-film adhesive may need to be printed to better support the load. As a variation, a disposable frame could be printed on only one side of the actuator film. This may be, for example, the side with the output bars, since that would have less support from the rigid surfaces of the substrate to support the pre-strain. Such techniques would reduce the overall thickness of the actuator module. Additional techniques include using film-to-film adhesives, making vias/interconnections, selectively curing regions of adhesives to make them more rigid to create an intrinsic frame, imbibing reactive material in the appropriate places and then curing them up.
The disposable frame 818 may be employed to hold or support a pre-stretched actuator film 806 before it is attached to a rigid substrate. In one embodiment, the disposable frame 818 material outside of the actuator film 806 area is disposable. Accordingly, after the frameless actuator 800 is attached to a desired cartridge, the disposable frame 818 can be cut out and discarded. In one embodiment, the disposable frame 818 layers may be required to hold an actuator film 806. The disposable frame 818 can be printed as a ripstop and one or more frames 818 may be formed on the opposite side of the actuator film 806. If additional stiffness is required, for a particular application, it may be desirable to replace the adhesive layer 816 with a frame material.
A die-cut polyethylene terephthalate (PET) material may be employed as the disposable frame 818. In one embodiment, the disposable frame 818 may be needed only on an output bar side. The opposite side to disposable frame 818 pattern side (bottom side) can be attached on a substrate first and then the disposable frame 818 can be cut out. In one embodiment, the pressure sensitive adhesive may be extended printed around the actuator film 806 to perform the same function of the disposable frame 818. In one embodiment, a pressure sensitive adhesive can be extended printed on an output bar disposable area to support a pre-strained film to form a disposable frame. The release liners 802, 804 can be attached on both sides of the actuator 800 and die-cut for singulation. A printed extended pressure sensitive adhesive disposable frame 818 area formed on the top output bar side can support a pre-strained film of the singulated actuator 800 cartridge after removing the release liners 802 on the bottom sides. After attaching the bottom side of the actuator 800 to a substrate, the disposable pressure sensitive adhesive disposable frame 818 can be cut out. In one embodiment, a silicone pressure sensitive adhesive disposable frame 818 would be suitable for holding a pre-strained actuator film 806 substrates for long-term cycles. Preliminary testing shows that silicone pressure sensitive adhesives have good adhesion for frame-pattern pressure sensitive adhesive applications after 65° C./85% testing. A stronger pressure sensitive adhesive than silicone such as an acrylic type pressure sensitive adhesive may be used for printing output bar patterns. Because acrylic does not have good adhesion to silicone film, one print of frame material for the output bar can be used as intermediate tie layer.
In
In
In
During assembly of frameless actuators, dielectric films tend to lift up and adhere or stick to the bottom plate after pressure is applied, which makes it difficult to lift up the output bars. A top plate having a protruded output bar helps when it is applied first and then the bottom frame part is applied to the substrate. A fixture may be employed to push out the films surrounding the output bar for multi-bar design (e.g., three-bar designs). A spacer can also be used. A via interconnection may be formed by making a hole, filling the via material at the thickness of the dielectric films, and removing the release liners without distorting the via material. In one embodiment, the via hole may be made with a hole punch or staple and filled with hot melt adhesive. The hole punch or staple makes the hole through the film and the hot melt will be deposited into the via hole. The hole punch or staple should have a bottom fixture having a thickness of the bottom release liner such that it just deposits the hot-melt to the thickness of the dielectric film. An anisotropic conductive adhesive may be employed to make an electrical connection from the via hole to the flex circuit.
It will be appreciated that alternative processes, materials, and design modifications may be made without departing from the scope of the frameless actuator according to the present disclosure. For example, in one embodiment, a stiffer material may be employed as an adhesive making the frameless actuator easier to assemble. In another embodiment, a stronger bottom pressure sensitive adhesive may be employed for the output bar without epoxy. In yet another embodiment of the fabrication process, the lamination process may be conducted prior to printing the pressure sensitive adhesives to avoid over curing of the top pressure sensitive adhesive. In one embodiment, the top pressure sensitive adhesive is thermal curable and the bottom pressure sensitive adhesive is ultra-violet (UV) curable. In yet another embodiment, a color may be employed for the top pressure sensitive adhesive to make it easy to recognize the top side from the bottom side. With extended pressure sensitive adhesive designs where the pressure sensitive adhesive is used as a frame surrounding the actuator film, if a flex circuit is needed, the extended pressure sensitive adhesive on the flex circuit region is not printed so that attachment of the frameless actuator to the flex circuit and cut-out of the extended pressure sensitive adhesive do not pose any issues.
As previously discussed, for EPAM based actuator modules to be incorporated with devices, consideration is given to the overall thickness of the actuator module. For example, a two-layer, three-bar actuator may be as thick as 500 μm. Reduction of the overall thickness of a actuator module includes reduction of the frame thickness or elimination of the frame from the design in favor of a frameless actuator as described herein. Flexible, frameless laminated film based actuators, however, are more challenging to place onto a substrate because the laminated films have been stretched up to 30%.
Two methods are provided for performing the singulation process. In one embodiment, an entire casing foil is prepared in size similar to the stretch frame and the casing foil is precut into multiple units in size of the final frameless actuator. The casing foil components may be held together on the original location by friction or a polymer film with a release agent coating.
In another embodiment, the entire size of the casing foil can be used for lamination, which is similar in size to the stretch frame. In accordance with this method, the casing is not cut into individual actuator units until the lamination process is completed. After the lamination process is completed, similar cutting methods can be used to singulate the individual units to cut the lamination films into separate units of frameless actuators, with the metal foil of the casing cut at the same time. The cutting methods comprise mechanical stamping, diamond sawing, or blade, laser or water jet cutting. Although this embodiment provides a simpler process, it also depends on selecting a cutting method that is compatible with the actuator film components to prevent destroying them in the process. For example, the mechanical forces, debris, and heat generated during the process should not damage or impair the frameless actuator components.
One embodiment of a method for fabricating and singulating individual frameless actuator film actuators will now be described. First, in one embodiment, the plate foil 1700 (or 1800 in another embodiment) is prepared cut in multiple units. As shown, the plate foil 1700 is cut into units 1702, where each unit has a size of about 36 mm×about 42 mm, for example, and defines a pre cut outline 1704. Other numbers of units and sizes may be selected, without limitation. Second, a multi-layer actuator film (e.g., the two-layer [2L] or four-layer [4L] actuator film 806 discussed in connection with
Various methods for fabricating and singulating individual frameless actuator film actuators according to the present disclosure have been described. In summary, two singulation techniques have been presented. A first method comprises preparing a casing foil of a size similar to the stretch frame, laminating the actuator films, and singulating by cutting both the actuator films and the casing foil. A second method comprises preparing a casing foil, cutting the casing foil into multiple units having roughly the size of the actuator film, holding the components together using friction or plastic films, laminating the actuator films, and singulating the actuator films by cutting with a blade, or other technique discussed above.
The described methods for fabricating and singulating individual frameless actuator film actuators provide several advantages. For example, such methods combine lamination and casing foil in one step. The casing foil can support the frameless film actuators even if removed from the stretch holder. The methods are compatible with frameless film actuators to minimize thickness. Singulation of the film actuators can be done together with casing. Accordingly, the methods provide a simplified lamination, casing, and singulation in one step. The described methods enable the production of frameless film actuators without sacrificing yield and efficiency. The process is compatible with quality control methodologies.
Accordingly, at process 2312, the frameless actuator 2320 is placed between top and bottom plates 2316, 2314 (e.g., substrates) and then compressed to collapse and bond the expandable adhesive 2308′, 2310′, shown in a collapsed state. In one embodiment, heat may be added during the compression process or after the compression process to bond the expandable adhesive 2308′, 2310′ to the top and bottom plates 2316, 2314.
In one embodiment, the process described in connection with the flow diagram 2300 shown in
Having described various embodiments of frameless actuators, it will be appreciated that a variety of techniques and materials may be employed to fabricate such devices. Accordingly, in various embodiments either very stiff or very strongly adhering adhesives may be employed for an adhesive to support a pre-strained film while being adhered to rigid substrates, such as those of devices, for example. In one embodiment, either the modulus of adhesive or adhesion strength may be greater than the compressive force of a pre-strained film which may be employed in frameless actuator devices. For multilayer frameless actuator devices, the film-to-film adhesive is of lesser concern because the same adhesive, which is either stiff or of strong adhesion, can be used as a film-to-film adhesive. Adhesives are not limited to pressure sensitive and expandable adhesives but can be chosen from a wide range of materials including hot melt adhesives, b-stageable adhesives, and UV curable adhesives. Rigid or high modulus versions of the latter materials may offer the advantage of non-sticky surfaces which do not require the use of release liners.
Broad categories of previously discussed devices include, for example, personal communication devices, handheld devices, and mobile telephones. In various aspects, a device may refer to a handheld portable device, computer, mobile telephone, smartphone, tablet personal computer (PC), laptop computer, and the like, or any combination thereof. Examples of smartphones include any high-end mobile phone built on a mobile computing platform, with more advanced computing ability and connectivity than a contemporary feature phone. Some smartphones mainly combine the functions of a personal digital assistant (PDA) and a mobile phone or camera phone. Other, more advanced, smartphones also serve to combine the functions of portable media players, low-end compact digital cameras, pocket video cameras, and global positioning system (GPS) navigation units. Modern smartphones typically also include high-resolution touch screens (e.g., touch surfaces), web browsers that can access and properly display standard web pages rather than just mobile-optimized sites, and high-speed data access via Wi-Fi and mobile broadband. Some common mobile operating systems (OS) used by modern smartphones include Apple's IOS, Google's ANDROID, Microsoft's WINDOWS MOBILE and WINDOWS PHONE, Nokia's Symbian, RIM's BlackBerry OS, and embedded Linux distributions such as MAEMO and MEEGO. Such operating systems can be installed on many different phone models, and typically each device can receive multiple OS software updates over its lifetime. A device also may include, for example, gaming cases for devices (IOS, ANDROID, WINDOWS PHONES, 3DS), gaming controllers or gaming consoles such as an XBOX console and PC controller, gaming cases for tablet computers (IPAD, GALAXY, XOOM), integrated portable/mobile gaming devices, haptic keyboard and mouse buttons, controlled resistance/force, morphing surfaces, morphing structures/shapes, among others.
It is to be appreciated that the embodiments described herein illustrate example implementations, and that the functional elements, logical blocks, program modules, and circuits elements may be implemented in various other ways which are consistent with the described embodiments. Furthermore, the operations performed by such functional elements, logical blocks, program modules, and circuits elements may be combined and/or separated for a given implementation and may be performed by a greater number or fewer number of components or program modules. As will be apparent to those of skill in the art upon reading the present disclosure, each of the individual embodiments described and illustrated herein has discrete components and features which may be readily separated from or combined with the features of any of the other several embodiments without departing from the scope of the present disclosure. Any recited method can be carried out in the order of events recited or in any other order which is logically possible.
It is worthy to note that any reference to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. The appearances of the phrase “in one embodiment” or “in one aspect” in the specification are not necessarily all referring to the same embodiment.
It is worthy to note that some embodiments may be described using the expression “coupled” and “connected” along with their derivatives. These terms are not intended as synonyms for each other. For example, some embodiments may be described using the terms “connected” and/or “coupled” to indicate that two or more elements are in direct physical or electrical contact with each other. The term “coupled,” however, may also mean that two or more elements are not in direct contact with each other, but yet still co-operate or interact with each other.
It will be appreciated that those skilled in the art will be able to devise various arrangements which, although not explicitly described or shown herein, embody the principles of the present disclosure and are included within the scope thereof. Furthermore, all examples and conditional language recited herein are principally intended to aid the reader in understanding the principles described in the present disclosure and the concepts contributed to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. Moreover, all statements herein reciting principles, embodiments, and embodiments as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents and equivalents developed in the future, i.e., any elements developed that perform the same function, regardless of structure. The scope of the present disclosure, therefore, is not intended to be limited to the exemplary embodiments and embodiments shown and described herein. Rather, the scope of present disclosure is embodied by the appended claims.
The terms “a” and “an” and “the” and similar referents used in the context of the present disclosure (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as,” “in the case,” “by way of example”) provided herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention. It is further noted that the claims may be drafted to exclude any optional element. As such, this statement is intended to serve as antecedent basis for use of such exclusive terminology as solely, only and the like in connection with the recitation of claim elements, or use of a negative limitation.
Groupings of alternative elements or embodiments disclosed herein are not to be construed as limitations. Each group member may be referred to and claimed individually or in any combination with other members of the group or other elements found herein. It is anticipated that one or more members of a group may be included in, or deleted from, a group for reasons of convenience and/or patentability.
While certain features of the embodiments have been illustrated as described above, many modifications, substitutions, changes and equivalents will now occur to those skilled in the art. It is therefore to be understood that the appended claims are intended to cover all such modifications and changes as fall within the scope of the disclosed embodiments and appended claims.
This application claims the benefit, under 35 USC §119(e), of U.S. provisional patent application numbers: 61/433,640, filed Jan. 18, 2011, entitled “FRAME-LESS DESIGN CONCEPT AND PROCESS”; 61/442,913, filed Feb. 15, 2011, entitled “FRAME-LESS DESIGN”; 61/447,827, filed Mar. 1, 2011, entitled “FRAMELESS ACTUATOR, LAMINATION AND CASING”; 61/477,712, filed Apr. 21, 2011, entitled “FRAMELESS APPLICATION”; and 61/545,292, filed Oct. 10, 2011, entitled “AN ALTERNATIVE TO Z-MODE ACTUATORS”; the entire disclosure of each of which is hereby incorporated by reference.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US2012/021511 | 1/17/2012 | WO | 00 | 11/7/2013 |
Number | Date | Country | |
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61433640 | Jan 2011 | US | |
61442913 | Feb 2011 | US | |
61447827 | Mar 2011 | US | |
61477712 | Apr 2011 | US | |
61545292 | Oct 2011 | US |