Haptic actuator having highly elastic polymer composition with high heat resistance - Patents.com

Abstract

A haptic actuator is provided that includes a housing having a top and a bottom and at least one sidewall between the top and bottom, first and second permanent magnets supported by the top and bottom of the housing, respectively, a field member supported by the housing and including at least one coil, first and second ends between the first and second permanent magnets, and optionally one or more mechanical reinforcements supported by the top of the housing, the bottom of the housing, or both. The haptic actuator includes a polymer composition having a melting temperature of about 250° C. or greater and a tensile modulus of about 16,000 MPa or greater, determined at a temperature of 23° C. according to ISO 527:2019.

Description

[Technical field]

[0001] Related Applications

[0001] This application is based on and claims the benefit of U.S. Provisional Patent Application No. 63 / 293,235, filed December 23, 2021, and U.S. Provisional Patent Application No. 63 / 402,997, filed September 1, 2022, which are incorporated herein by reference. [Background technology]

[0002]

[0002] Haptic technology is becoming increasingly popular as a method of conveying information to a user. Haptic technology, which may also be simply referred to as haptics, is a tactile feedback-based technology that stimulates a user's sense of touch by applying a relative amount of force to the user.

[0003]

[0003] A haptic device or actuator is an example of a device that provides tactile feedback to a user. In particular, a haptic device or actuator can apply a relative amount of force to a user by actuating a mass that is part of the haptic device. Information can be conveyed to a user by generating various forms of tactile feedback, such as relatively long and short bursts of force or vibration.

[0004]

[0004] It is generally desirable for the polymer components used in haptic actuators to have high creep resistance and stiffness. Furthermore, because assembly of electronic devices that include haptic actuators can involve exposure of the haptic actuators to high temperatures, it is also desirable for the polymer components to have high heat resistance.

[0005]

[0005] Therefore, there is a need for a haptic actuator that includes a material that is highly stiff and heat resistant. Summary of the Invention

[0006] According to one embodiment of the present invention, a haptic actuator is provided. The haptic actuator includes a housing having a top and a bottom and at least one sidewall between the top and bottom, first and second permanent magnets supported by the top and bottom of the housing, respectively, a field member supported by the housing and including at least one coil, first and second ends between the first and second permanent magnets, and optionally one or more mechanical reinforcements supported by the top of the housing, the bottom of the housing, or both. The haptic actuator includes a polymer composition having a melting temperature of about 250° C. or greater and a tensile modulus of about 16,000 MPa or greater, determined at 23° C. according to ISO 527:2019.

[0007]

[0007] Other features and aspects of the present invention are set forth in greater detail below.

[0008] A full and enabling disclosure of the present invention, including the best mode thereof to one of ordinary skill in the art, is set forth more particularly in the remainder of the specification, including references to the accompanying drawings, in which: [Brief description of the drawings]

[0008] [Figure 1]

[0009] FIG. 1 is a perspective view of a portion of a haptic actuator according to one embodiment of the present invention. [Diagram 2]

[0010] FIG. 2 is an exploded perspective view of the haptic actuator of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009]

[0011] Those skilled in the art will appreciate that this discussion describes exemplary embodiments only, and is not intended as limiting the broader aspects of the invention.

[0012] Generally speaking, the present invention relates to a haptic actuator comprising a polymer composition comprising a polymer matrix and a plurality of reinforcing fibers, the polymer composition having a unique combination of stiffness and high heat resistance that allows it to perform well in the haptic actuator. For example, the tensile modulus of the composition is generally about 16,000 MPa or more, in some embodiments about 20,000 MPa or more, in some embodiments about 20,500 MPa to about 40,000 MPa, in some embodiments about 21,000 MPa to about 36,000 MPa, in some embodiments about 22,000 MPa to about 25,000 MPa, in some embodiments about 30,000 MPa to about 36,000 MPa, as determined at 23°C according to ISO527:2019. Furthermore, the melting temperature of the composition is generally about 250°C or more, in some embodiments about 280°C or more, in some embodiments about 290°C or more, in some embodiments about 300°C or more, in some embodiments about 310°C to about 360°C.

[0010]

[0013] The composition may also exhibit a tensile strength of from about 120 to about 500 MPa, in some embodiments from about 130 to about 400 MPa, and in some embodiments, from about 140 to about 350 MPa, and / or a tensile strain at break of greater than or equal to about 0.3%, in some embodiments, from about 0.5% to about 5%, and in some embodiments, from about 0.8% to about 3%, as determined at 23° C. according to ISO 527:2019. The polymeric composition may also exhibit a flexural modulus of about 15,000 MPa or more, in some embodiments about 19,000 MPa to about 40,000 MPa, in some embodiments about 20,000 MPa to about 25,000 MPa, and in some embodiments about 30,000 MPa to about 35,000 MPa, a flexural strength of about 100 to about 500 MPa, in some embodiments about 150 to about 400 MPa, and in some embodiments about 200 to about 350 MPa, and / or a flexural strain at break of about 0.3% or more, in some embodiments about 0.8% to about 5%, and in some embodiments about 1.4% to about 3%, as determined at 23° C. according to ISO 179-1:2010. 2In some embodiments, about 10 to about 30 kJ / m 2 and in some embodiments, from about 15 to about 25 kJ / m 2 Charpy notched impact strength of approximately 10 kJ / m 2 or more, in some embodiments, about 15 kJ / m 2 ~about 50kJ / m 2 and in some embodiments, from about 20 to about 45 kJ / m 2 and in some embodiments, from about 25 to about 35 kJ / m 2 In addition, the deflection temperature under load (DTUL) may be about 180° C. or greater, in some embodiments from about 200° C. to about 350° C., in some embodiments from about 225° C. to about 325° C., and in some embodiments from about 240° C. to about 300° C., as measured at a specified load of 1.8 MPa in accordance with ASTM D648-18 (technically equivalent to ISO 75-2:2013).

[0011]

[0014] Further, the polymer composition is -1 and / or a melt viscosity of about 300 Pa·s or less, in some embodiments about 200 Pa·s or less, in some embodiments about 100 Pa·s or less, in some embodiments about 10 to about 90 Pa·s, in some embodiments about 10 to about 80 Pa·s, and in some embodiments about 30 to about 60 Pa·s, determined at a shear rate of 1000 s. -1 The composition may have a melt viscosity of about 200 Pa·s or less, in some embodiments about 100 Pa·s or less, in some embodiments about 10 to about 70 Pa·s, in some embodiments about 10 to about 60 Pa·s, and in some embodiments about 30 to about 45 Pa·s, determined at a shear rate of 15° C. above the melting temperature of the composition according to ISO 11443:2021.

[0012]

[0015] Various embodiments of the invention will now be described in more detail. I. Polymer Composition A. Polymer matrix

[0016] The polymer matrix typically contains one or more liquid crystal polymers, generally in an amount of about 30 wt.% to about 90 wt.%, in some embodiments about 45 wt.% to about 75 wt.%, in some embodiments about 50 wt.% to about 70 wt.%, and in some embodiments about 55 wt.% to about 65 wt.% of the total polymer composition. Liquid crystal polymers are generally classified as "thermotropic" insofar as they can have a rod-like structure and exhibit crystalline behavior in their molten state (e.g., a thermotropic nematic state). The liquid crystal polymers used in the polymer composition can have a melting temperature of about 200°C or higher, in some embodiments about 220°C to about 350°C, and in some embodiments about 260°C to about 330°C, provided that the melting point of the total composition is about 280°C or higher. The melting temperature can be determined as is known in the art using differential scanning calorimetry ("DSC"), for example as determined by ISO test number 11357-3:2011. Such polymers can be formed from one or more types of repeat units, as is known in the art. Liquid crystal polymers, for example, generally have the following formula (I):

[0013] [ka]

[0014] [In the formula, Ring B is a substituted or unsubstituted 6-membered aryl group (e.g., 1,4-phenylene or 1,3-phenylene), a substituted or unsubstituted 6-membered aryl group fused to a substituted or unsubstituted 5- or 6-membered aryl group (e.g., 2,6-naphthalene), or a substituted or unsubstituted 6-membered aryl group bonded to a substituted or unsubstituted 5- or 6-membered aryl group (e.g., 4,4-biphenylene); Y1 and Y2 are independently O, C(O), NH, C(O)HN, or NHC(O). The aromatic ester may contain one or more aromatic ester repeat units represented by:

[0015]

[0017] Typically, at least one of Y1 and Y2 is C(O). Examples of such aromatic ester repeat units can include, for example, aromatic dicarboxylic acid repeat units (Y1 and Y2 in formula I are C(O)), aromatic hydroxycarboxylic acid repeat units (Y1 is O and Y2 is C(O) in formula I), and various combinations thereof.

[0016]

[0018] For example, aromatic hydroxycarboxylic acid repeat units derived from aromatic hydroxycarboxylic acids such as 4-hydroxybenzoic acid, 4-hydroxy-4'-biphenylcarboxylic acid, 2-hydroxy-6-naphthoic acid, 2-hydroxy-5-naphthoic acid, 3-hydroxy-2-naphthoic acid, 2-hydroxy-3-naphthoic acid, 4'-hydroxyphenyl-4-benzoic acid, 3'-hydroxyphenyl-4-benzoic acid, 4'-hydroxyphenyl-3-benzoic acid, and the like, as well as alkyl, alkoxy, aryl, and halogen substituents thereof, and combinations thereof, may be used. Particularly suitable aromatic hydroxycarboxylic acids are 4-hydroxybenzoic acid ("HBA") and 6-hydroxy-2-naphthoic acid ("HNA"). When used, repeat units derived from hydroxycarboxylic acids (e.g., HBA and / or HNA) typically comprise about 30 mol% or more of the polymer, in some embodiments from about 40 mol% to about 80 mol%, and in some embodiments from about 50 mol% to 70 mol%.

[0017]

[0019] Aromatic dicarboxylic acid repeat units derived from aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, diphenyl ether-4,4'-dicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 4,4'-dicarboxybiphenyl, bis(4-carboxyphenyl)ether, bis(4-carboxyphenyl)butane, bis(4-carboxyphenyl)ethane, bis(3-carboxyphenyl)ether, bis(3-carboxyphenyl)ethane, and the like, as well as alkyl, alkoxy, aryl, and halogen substituents thereof, and combinations thereof, may also be used. Particularly suitable aromatic dicarboxylic acids may include, for example, terephthalic acid ("TA"), isophthalic acid ("IA"), and 2,6-naphthalenedicarboxylic acid ("NDA"). When used, repeat units derived from aromatic dicarboxylic acids (e.g., IA, TA, and / or NDA) typically each comprise from about 1 mol % to about 50 mol %, in some embodiments from about 2 mol % to about 40 mol %, and in some embodiments, from about 5 mol % to about 30 mol % of the polymer.

[0018]

[0020] Other repeat units may also be used in the polymer. In certain embodiments, repeat units derived from aromatic diols such as, for example, hydroquinone, resorcinol, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 4,4'-dihydroxybiphenyl (or 4,4'-biphenol), 3,3'-dihydroxybiphenyl, 3,4'-dihydroxybiphenyl, 4,4'-dihydroxybiphenyl ether, bis(4-hydroxyphenyl)ethane, and the like, as well as their alkyl, alkoxy, aryl and halogen substituents, and combinations thereof, may be used. Particularly suitable aromatic diols may include, for example, hydroquinone ("HQ") and 4,4'-biphenol ("BP"). When used, repeat units derived from aromatic diols (e.g., HQ and / or BP) typically comprise from about 1 mol% to about 30 mol%, in some embodiments from about 2 mol% to about 25 mol%, and in some embodiments from about 5 mol% to about 20 mol% of the polymer, respectively. Repeat units such as those derived from aromatic amides (e.g., acetaminophen ("APAP")) and / or aromatic amines (e.g., 4-aminophenol ("AP"), 3-aminophenol, 1,4-phenylenediamine, 1,3-phenylenediamine, etc.) may also be used. When used, repeat units derived from aromatic amides (e.g., APAP) and / or aromatic amines (e.g., AP) typically comprise from about 0.1 mol% to about 20 mol%, in some embodiments from about 0.5 mol% to about 15 mol%, and in some embodiments from about 1 mol% to about 10 mol% of the polymer. It should also be understood that various other monomeric repeat units may be incorporated into the polymer. For example, in certain embodiments, a polymer may contain one or more repeat units derived from non-aromatic monomers, such as aliphatic or alicyclic hydroxycarboxylic acids, dicarboxylic acids, diols, amides, amines, etc. Of course, in other embodiments, a polymer may be "fully aromatic" in that it lacks repeat units derived from non-aromatic (e.g., aliphatic or alicyclic) monomers.

[0019]

[0021] In some embodiments, the composition contains a "low naphthenic" liquid crystal polymer that contains a low content of repeat units derived from naphthenic hydroxycarboxylic acids and naphthenic dicarboxylic acids, such as naphthalene-2,6-dicarboxylic acid ("NDA"), 6-hydroxy-2-naphthoic acid ("HNA"), or a combination thereof. That is, the total amount of repeat units derived from naphthenic hydroxycarboxylic acids and / or dicarboxylic acids (e.g., NDA, HNA, or a combination of HNA and NDA) can be about 15 mol% or less of the polymer, in some embodiments about 10 mol% or less, in some embodiments about 6 mol% or less, and in some embodiments 0 mol% to about 5 mol%. In one embodiment, for example, the repeat units derived from HNA and / or NDA can be 0 mol% of the polymer. In such embodiments, the polymer can contain repeat units derived from HBA in an amount of about 40 mol% to about 80 mol%, in some embodiments about 45 mol% to about 75 mol%, and in some embodiments about 50 mol% to about 70 mol%. The polymer may also contain aromatic dicarboxylic acids (e.g., IA and / or TA) in amounts of about 1 mol% to about 20 mol%, in some embodiments about 4 mol% to about 15 mol%, and / or aromatic diols (e.g., BP and / or HQ) in amounts of about 1 mol% to about 20 mol%, in some embodiments about 4 mol% to about 15 mol%. In certain examples, the molar ratio of BP to HQ may be selectively controlled to be about 0.8 to about 2.5, in some embodiments about 1 to about 2.2, in some embodiments about 1.1 to about 2, and / or the molar ratio of TA to IA may be selectively controlled to be about 0.8 to about 2.5, in some embodiments about 1 to about 2.2, in some embodiments about 1.1 to about 2. For example, BP may be used in a molar amount greater than HQ such that the molar ratio is greater than 1, and / or TA may be used in a molar amount greater than IA such that the molar ratio is greater than 1.

[0020]

[0022] In some embodiments, the polymer composition contains a "highly naphthenic" liquid crystal polymer that contains a relatively high content of repeat units derived from naphthenic hydroxycarboxylic acids and naphthenic dicarboxylic acids, such as naphthalene-2,6-dicarboxylic acid ("NDA"), 6-hydroxy-2-naphthoic acid ("HNA"), or a combination thereof. That is, the total amount of repeat units derived from naphthenic hydroxycarboxylic acids and / or dicarboxylic acids (e.g., NDA, HNA, or a combination of HNA and NDA) can be greater than about 15 mol%, in some embodiments about 18 mol% or more, and in some embodiments, about 20 mol% to about 60 mol% of the polymer. In one particular embodiment, for example, repeat units derived from 6-hydroxy-2-naphthoic acid ("HNA") can comprise about 10 mol% to about 40 mol%, in some embodiments about 15 mol% to about 35 mol%, and in some embodiments about 20 mol% to about 30 mol% of the polymer. In such embodiments, the liquid crystal polymer may also contain various other monomers such as aromatic hydroxycarboxylic acids (e.g., HBA) in amounts of about 10 mol% to about 85 mol%, in some embodiments about 40 mol% to about 82 mol%, and in some embodiments about 70 mol% to about 80 mol%, aromatic dicarboxylic acids (e.g., IA and / or TA) in amounts of about 0 mol% to about 30 mol%, in some embodiments about 2 mol% to about 25 mol%, and / or aromatic diols (e.g., BP and / or HQ) in amounts of about 0 mol% to about 40 mol%, and in some embodiments about 2 mol% to about 35 mol%. In some embodiments, the high naphthenic liquid crystal polymer contains a small amount of aromatic dicarboxylic acid in addition to the naphthenic hydroxycarboxylic acid and HBA. For example, the liquid crystal polymer may contain TA and / or IA in amounts of about 0.1 mol% to about 5 mol%, in some embodiments about 0.2 mol% to about 2 mol%, and in some embodiments about 0.5 mol% to about 1 mol%.

[0021]

[0023] In certain embodiments, all of the liquid crystal polymers are "low naphthenic" polymers as described above. In other embodiments, all of the liquid crystal polymers are "high naphthenic" polymers as described above. In some cases, blends of such polymers may also be used. For example, the low naphthenic liquid crystal polymer may comprise from about 50 wt.% to about 95 wt.%, in some embodiments from about 60 wt.% to about 90 wt.%, in some embodiments from about 75 wt.% to about 85 wt.%, of the total amount of liquid crystal polymer in the composition, and the high naphthenic liquid crystal polymer may comprise from about 5 wt.% to about 50 wt.%, in some embodiments from about 10 wt.% to about 40 wt.%, in some embodiments from about 15 wt.% to about 25 wt.%. In other embodiments, the high naphthenic liquid crystalline polymer may comprise from about 50 wt.% to about 99 wt.%, in some embodiments from about 80 wt.% to about 97 wt.%, and in some embodiments from about 90 wt.% to about 95 wt.%, of the total amount of liquid crystalline polymer in the composition, and the low naphthenic liquid crystalline polymer may comprise from about 1 wt.% to about 50 wt.%, in some embodiments from about 3 wt.% to about 20 wt.%, and in some embodiments from about 5 wt.% to about 10 wt.% of the total amount of liquid crystalline polymer in the composition.

[0022] B. Reinforced Fiber

[0024] To provide such a polymeric composition with a high modulus, reinforcing fibers are typically dispersed within the polymer matrix. In general, any of a variety of different types of reinforcing fibers may be used in the polymeric composition of the present invention, such as polymeric fibers, metal fibers, carbonaceous fibers (e.g., graphite, carbide, etc.), inorganic fibers, etc., and combinations thereof. In some embodiments, the composition contains inorganic fibers, such as those derived from glass, titanates (e.g., potassium titanate), neosilicates, sorosilicates, inosilicates (e.g., calcium inosilicates such as wollastonite, calcium magnesium inosilicates such as tremolite, calcium magnesium iron inosilicates such as actinolite, magnesium iron inosilicates such as anthophyllite, etc.), phyllosilicates (e.g., aluminum phyllosilicates such as palygorskite), silicates such as tectosilicates, sulfates such as calcium sulfate (e.g., dehydrated gypsum or anhydrite), mineral wool (e.g., rock wool or slag wool), etc. Glass fibers, such as those formed from E-glass, A-glass, C-glass, D-glass, AR-glass, R-glass, S1-glass, S2-glass, and the like, and mixtures thereof, may be particularly suitable for use in the present invention. Carbon fibers, such as polyacrylonitrile (PAN)-based or pitch-based carbon fibers, also generally have high stiffness and are therefore particularly suitable for use in the polymer composition. If desired, the reinforcing fibers may be provided with a size or other coating as known in the art.

[0023]

[0025] The amount of reinforcing fibers can be selectively controlled to achieve the desired combination of stiffness and heat resistance. Reinforcing fibers can be used, for example, in an amount of about 10% to about 70%, in some embodiments about 20% to about 60%, in some embodiments about 30% to about 55%, in some embodiments about 35 wt.% to about 50 wt.%, and in some embodiments about 35% to about 45% by weight of the polymer composition. In some embodiments, the reinforcing fibers include only glass fibers. In other embodiments, the composition contains both glass fibers and carbon fibers. In such embodiments, the ratio of glass fibers to carbon fibers can be about 1:10 to about 25:1, in some embodiments about 1:1 to about 20:1, in some embodiments about 2:1 to about 15:1, in some embodiments about 5:1 to about 15:1, and in some embodiments about 6:1 to about 13:1. For example, in one embodiment, the glass fibers may comprise from about 10 wt.% to about 50 wt.%, in some embodiments from about 15 wt.% to about 45 wt.%, and in some embodiments, from about 25 wt.% to about 40 wt.%, while the carbon fibers may comprise from about 0.5 wt.% to about 10 wt.%, in some embodiments, from about 1 wt.% to about 8 wt.%, and in some embodiments, from about 1.5 wt.% to about 7 wt.% of the composition.

[0024]

[0026] In some embodiments, the reinforcing fibers may include only carbon fibers. In such embodiments, the carbon fibers may comprise about 10 wt.% to about 50 wt.%, such as about 25 wt.% to about 40 wt.%, of the composition. The inventors have discovered that haptic actuators made from compositions using carbon fibers as the reinforcing fibers may be quieter than those formed from compositions using glass fibers as the reinforcing fibers.

[0025] C. Optional Ingredients

[0027] A wide variety of additional additives may also be included in the polymer composition, such as particulate fillers (e.g., talc, mica, etc.), antimicrobial agents, pigments (e.g., carbon black), antioxidants, stabilizers, surfactants, waxes, solid solvents, flame retardants, anti-drip additives, and other materials added to improve properties and processability. Lubricants capable of withstanding the processing conditions of the liquid crystal polymer without substantial degradation may also be used in the polymer composition. Examples of such lubricants include fatty acid esters, their salts, esters, fatty acid amides, organic phosphate esters, and hydrocarbon waxes of the type commonly used as lubricants in the processing of engineering plastic materials, including mixtures thereof. Suitable fatty acids typically have a backbone carbon chain of about 12 to about 60 carbon atoms, such as myristic acid, palmitic acid, stearic acid, arachidic acid, montanic acid, octadecinic acid, parinric acid, and the like. Suitable esters include fatty acid esters, fatty alcohol esters, wax esters, glycerol esters, glycol esters, and complex esters. Fatty acid amides include fatty primary amides, fatty secondary amides, methylene and ethylene bisamides, and alkanolamides, such as palmitic acid amide, stearic acid amide, oleic acid amide, N,N'-ethylene bisstearamide, and the like. Metal salts of fatty acids, such as calcium stearate, zinc stearate, magnesium stearate, and the like; hydrocarbon waxes, including paraffin wax, polyolefin wax, and oxidized polyolefin wax, and microcrystalline wax, are also suitable. Particularly suitable lubricants are stearic acid, salts, or amides, such as pentaerythritol tetrastearate, calcium stearate, or N,N'-ethylene bisstearamide. When used, the lubricant typically comprises from about 0.05 wt.% to about 1.5 wt.%, and in some embodiments from about 0.1 wt.% to about 0.5 wt.% (by weight) of the polymer composition.

[0026]

[0028] The components used to form the polymer composition may be combined together using any of a variety of different techniques as known in the art. In one particular embodiment, for example, the liquid crystal polymer, reinforcing fibers, and other optional additives are melt processed as a mixture in an extruder to form the polymer composition. The mixture may be melt kneaded in a single screw extruder or a multi-screw extruder, such as at a temperature of about 250°C to about 450°C. In one embodiment, the mixture may be melt processed in an extruder that includes multiple temperature zones. The temperature of the individual zones is typically set within about -60°C to about 25°C relative to the melt temperature of the polymer. For example, the mixture may be melt processed using a twin screw extruder, such as a Leistritz 18mm co-rotating fully intermeshing twin screw extruder. A versatile screw design may be used to melt process the mixture. In one embodiment, the mixture including all the components may be fed by a volumetric feeder to the feed throat of the first barrel. In another embodiment, different components may be added at different addition points in the extruder, as is known. For example, the polymer may be applied at the feed throat and certain additives (e.g., reinforcing fibers) may be fed downstream at the same or different temperature zones. The resulting mixture may then be melted and mixed and then extruded through a die. The extruded polymer composition may then be quenched in a water bath to solidify and pelletized in a pelletizer, followed by drying.

[0027] II. Haptic Actuators

[0029] As shown above, the polymer composition of the present invention can be used in a haptic actuator.Typically, the haptic actuator comprises a housing having a top and a bottom and at least one sidewall between the top and the bottom, a first and a second permanent magnet supported by the top and the bottom of the housing, respectively, a field member supported by the housing and including at least one coil, a first and a second end between the first and the second permanent magnet, and optionally one or more mechanical reinforcements supported by the top of the housing, the bottom of the housing, or both.

[0028]

[0030] 1 and 2, one embodiment of a haptic actuator 40 includes a housing 41 having a top 42, a bottom 43, and a sidewall 46. The housing 41 has a rectangular shape. Of course, the housing 41 may be another shape and have different dimensions.

[0029]

[0031] Each mechanical stiffener 47, 48 may be supported by the top 42 and bottom 43 of the housing 41. Each mechanical stiffener 47, 48 may be non-ferritic, and more specifically, non-ferritic steel. Any number of mechanical stiffeners, including zero, may be used and may be supported by any portion of the housing 41.

[0030]

[0032] The haptic actuator 40 also includes first and second coils 44, 45 (i.e., electrical coils) supported, respectively, by the top and bottom portions 42, 43 of the housing 41. The first and second coils 44, 45 each have a loop or "racetrack" shape and are aligned and spaced apart in a stacked relationship, as shown.

[0031]

[0033] Haptic actuator 40 may also include a field member 50 supported by housing 41. Field member 50 includes permanent magnets 51, 52 between first and second coils 44, 45, as shown, and is movable within housing 41. While the movement of field member 50 may be described as being movable in one direction, i.e., a linear haptic actuator, it should be understood that in some embodiments, the field member may be movable in the other direction, i.e., an angular haptic actuator, or a combination of both linear and angular haptic actuators.

[0032]

[0034] The permanent magnets 51, 52 may be, for example, neodymium and may be positioned in opposite directions relative to their respective poles. The permanent magnets 51, 52 also have a rectangular shape and are aligned along the length of the first and second coils 44, 45. While a pair of rectangular shaped permanent magnets are illustrated, it will be understood that there may be any number of permanent magnets having any shape between the first and second coils 44, 45.

[0033]

[0035] The field member 50 also includes first and second ends 53,54. The first and second ends 53,54 have first and second sets of protrusions 55,56, respectively, for coupling to the first and second sets of bias members 71,72. The first and second sets of protrusions 55,56 are in the shape of circular protrusions as shown and extend outwardly in opposite directions. There may be an equal number of protrusions extending in each direction.

[0034]

[0036] The field member 50 includes a first mass 57 between the first end 53 and the pair of permanent magnets 51, 52. A second mass 58 is between the second end 54 and the pair of permanent magnets 51, 52. A third mass 59 extends between the first and second masses 57, 58. The third mass 59 has a reduced width relative to the first and second masses 57, 58. This allows the permanent magnets 51, 52 to be on either side of the third mass 59. In some embodiments, the third mass 59 may not be included and / or may have a different shape, for example. Each of the first, second, and third masses 57, 58, 59 may be, for example, tungsten. Each of the first, second, and third mass bases may be of a different material.

[0035]

[0037] The first, second and third masses 57, 58, 59, which may be collectively referred to as the "moving portion", are spaced apart by a relatively small gap from the first and second coils 44, 45. In other words, the first and second coils 44, 45 do not contact the first, second and third masses 57, 58, 59.

[0036]

[0038] The haptic actuator 40 also includes a first shaft 61 that slidably couples the first mass 57 to the housing 41. A second shaft 62 slidably couples the second mass 58 to the housing 41. The first and second shafts 61, 62 can be, for example, a nickel-chromium alloy. The first and second shafts 61, 62 can be approximately parallel to one another and can limit motion to a desired translational movement that can be parallel to the y-axis (width), as will be appreciated by those skilled in the art. The first and second shafts 61, 62 can also limit motion in other directions, for example, lateral movement, rotation, and / or rocking.

[0037]

[0039] The first and second mechanical bearings 63, 64 are carried by the first and second masses 57, 58 and slidably receive the first and second shafts. The first and second mechanical bearings 63, 64 may be slot bearings.

[0038]

[0040] Those skilled in the art will appreciate that the first and second shafts 61, 62 can slide against a combination of circular and slot bearings 63, 64, thus constraining forces in undesired directions while reducing the possibility of interference from over-containment. The first and second mechanical bearings can be mounted on the moving masses 57, 58, 59 (and thus the shafts 61, 62 are fixed to the housing 41) or on the housing (and thus the shafts are fixed to the moving masses).

[0039]

[0041] The haptic actuator 50 also includes a first set of bias members 71 between the first end 53 of the field member 50 and the housing 41, and a second set of bias members 72 between the second end 54 of the field member and the housing. The first and second sets of bias members 71, 72 may be, for example, springs, more specifically, coil springs and / or leaf springs, and may be steel. The first and second sets of bias members 71, 72 may be other types of bias members and may be another material. As discussed above, the first, second, and third masses are spaced apart from the first and second coils 44, 45. The first and second sets of bias members 71, 72 help maintain this spacing and provide increased stiffness. Although a total of twelve bias members are shown in the form of coil springs (i.e., mechanical coils), it should be understood that any number and type of bias members may be used. Each of the first and second sets of bias members 71, 72 may, for example, have an equal number between each one of the first and second ends 44, 45 and an adjacent portion of the housing, respectively.

[0040]

[0042] It is noted that the polymer composition of the present invention may be used in any of the various parts of the haptic actuator. For example, referring again to Figures 1 and 2, the polymer composition may be used to form all or part of the housing 41, including the top 42, bottom 43, and sidewalls 46. The desired parts may be formed using a variety of different techniques. Suitable techniques may include, for example, injection molding, low pressure injection molding, extrusion compression molding, gas injection molding, foam injection molding, low pressure gas injection molding, low pressure foam injection molding, gas extrusion compression molding, foam extrusion compression molding, extrusion molding, foam extrusion molding, compression molding, foam compression molding, gas compression molding, and the like. For example, an injection molding system may be used that includes a mold into which the polymer composition may be injected. The time in the injector may be controlled and optimized so that the polymer matrix does not pre-solidify. Once the cycle time is reached and the barrel is full for ejection, a piston may be used to inject the composition into the mold cavity. Compression molding systems may also be used. Similar to injection molding, shaping of the polymer composition into the desired article also occurs in the mold. The composition can be placed into a compression mold using any known technique, such as by being picked up by an automated robotic arm. The temperature of the mold can be maintained at or above the solidification temperature of the polymer matrix for a desired period of time to allow solidification. The molded product can then be solidified by bringing it to a temperature below the melting temperature. The resulting product can be demolded. The cycle time of each molding process can be tailored to the polymer matrix to achieve sufficient bonding and improve overall process productivity.

[0041]

[0043] The resulting haptic actuators can be used in a wide variety of electronic devices, such as portable electronic devices (eg, mobile phones, portable computers, tablets, watches, etc.), as known in the art.

[0042]

[0044] The invention may be better understood with reference to the following examples. Test Method

[0045] Melt viscosity: Melt viscosity (Pa·s) is measured at 1,000 s according to ISO test number 11443:2021. -1 or 400s -1 and a temperature 15°C above the melt temperature. The rheometer orifice (die) had a diameter of 1 mm, a length of 20 mm, an L / D ratio of 20.1, and an entrance angle of 180°. The barrel diameter was 9.55 mm + 0.005 mm and the rod length was 233.4 mm.

[0043]

[0046] Melting temperature: Melting temperature ("Tm") may be determined by differential scanning calorimetry ("DSC") as known in the art. Melting temperature is the differential scanning calorimetry (DSC) peak melting temperature as determined by ISO test number 11357-2:2020. In the DSC procedure, samples were heated and cooled at 20°C per minute as described in ISO standard 10350, using DSC measurements performed on a TA Q2000 instrument.

[0044]

[0047] Deflection Temperature Under Load ("DTUL"): Deflection under load temperature may be determined according to ISO Test No. 75-2:2013 (technically equivalent to ASTM D648-18). More specifically, a specimen sample with a length of 80 mm, a thickness of 10 mm, and a width of 4 mm may be subjected to an edgewise three-point bending test with a specified load (maximum external fiber stress) of 1.8 megapascals. The sample may be lowered into a silicone oil bath where the temperature is increased at 2°C per minute until the sample deflects 0.25 mm (0.32 mm per ISO Test No. 75-2:2013).

[0045]

[0048] Tensile modulus, tensile stress, and tensile elongation: Tensile properties may be tested according to ISO test number 527:2019 (technically equivalent to ASTM D638-14). Modulus and strength measurements may be performed on the same specimen sample with a length of 80 mm, a thickness of 10 mm, and a width of 4 mm. The test temperature may be 23°C, and the test speed may be 1 or 5 mm / min.

[0046]

[0049] Flexural modulus, flexural stress, and flexural elongation: Flexural properties may be tested according to ISO test number 178:2019 (technically equivalent to ASTM D790-10). The test may be performed on a 64 mm support span. The test may be performed on the center portion of an uncut ISO 3167 utility bar. The test temperature may be 23° C. and the test speed may be 2 mm / min.

[0047]

[0050] Charpy Impact Strength: Charpy properties may be tested according to ISO test number ISO179-1:2010 (technically equivalent to ASTM D256-10, Method B). This test may be performed using a Type 1 specimen size (80 mm length, 10 mm width, and 4 mm thickness). When testing notched impact strength, the notch may be a Type A notch (0.25 mm base radius). The specimen may be cut from the center of a utility bar using a single tooth milling machine. The test temperature may be 23°C.

[0048] Examples 1 to 5

[0051] Samples 1-5 are formed from various proportions of LCP1, LCP2, LCP3, LCP4, glass fiber, carbon fiber, carbon black, and lubricant, as shown in Table 1. LCP1 is formed from approximately 60 mol% HBA, 13 mol% TA, 12 mol% BP, 8 mol% HQ, and 7 mol% IA. LCP2 is formed from approximately 62.5 mol% HBA, 5 mol% HNA, 16.4 mol% TA, 11.2 mol% BP, and 5 mol% APAP. LCP3 is formed from 73 mol% HBA and 27 mol% HNA. LCP4 is formed from 79.3 mol% HBA, 20 mol% HNA, and 0.7 mol% TA. Values ​​are listed in weight percent of total composition.

[0049] [Table 1]

[0050]

[0052] Parts are injection molded into plaques from the samples of Examples 1-5 and tested for mechanical properties, with the results shown in Table 2 below.

[0051] [Table 2]

[0052] Examples 6 to 10

[0053] Samples 6-10 are formed from various proportions of LCP3, LCP4, carbon fiber, and lubricant, as shown in Table 3.

[0053] [Table 3]

[0054] Parts are injection molded into plaques from the samples of Examples 6-10 and tested for mechanical properties, with the results shown in Table 4 below.

[0055] [Table 4]

[0056]

[0055] These and other modifications and variations of the present invention may be practiced by those skilled in the art without departing from the spirit and scope of the present invention. It should further be understood that aspects of the various embodiments may be interchanged, either in whole or in part. Furthermore, those skilled in the art will appreciate that the foregoing description is merely exemplary and is not intended to limit the invention as further described in such appended claims.

Claims

1. A haptic actuator, a housing having a top and a bottom and at least one sidewall between the top and bottom; first and second permanent magnets respectively supported by the top and bottom of the housing; a field member carried by the housing and including at least one coil between the first and second permanent magnets and having first and second ends; Optionally, one or more mechanical stiffeners supported by the top of the housing, the bottom of the housing, or both; Including, The haptic actuator comprises a polymer composition having a melting temperature of about 250° C. or greater and a tensile modulus of about 16,000 MPa or greater, determined at a temperature of 23° C. according to ISO 527:2019.

2. 10. The haptic actuator of claim 1, wherein the polymer composition has a hardness of 400 seconds according to ISO 11443:2021. －１ and at a temperature 15° C. greater than the melting temperature of the composition, the haptic actuator exhibiting a melt viscosity of 200 Pa·s or less.

3. 10. The haptic actuator of claim 1, wherein the polymer composition exhibits a flexural modulus, determined at 23° C. according to ISO 178:2019, of about 15,000 MPa or greater.

4. 10. The haptic actuator of claim 1, wherein the polymer composition has a modulus of about 10 kJ / m, determined at 23° C. according to ISO 179-1:2010. ２ A haptic actuator exhibiting a Charpy notch-free impact strength of at least 100 MPa.

5. 10. The haptic actuator of claim 1, wherein the polymer composition has a modulus of about 5 kJ / m2 as determined at 23° C. according to ISO 179-1:2010. ２ A haptic actuator exhibiting a Charpy notched impact strength of or greater.

6. The haptic actuator of claim 1 , wherein the polymer composition exhibits a tensile strength, determined according to ISO 527:2019, of about 120 to about 500 MPa.

7. The haptic actuator of claim 1 , wherein the polymer composition exhibits a deflection temperature under load of about 180° C. or greater, measured at a specified load of 1.8 MPa according to ISO 75-2:2013.

8. 10. The haptic actuator of claim 1, wherein the polymer composition exhibits a flexural modulus of greater than or equal to about 15,000 MPa, determined at 23° C. according to ISO Test No. 178:2019.

9. 10. The haptic actuator of claim 1, wherein the polymer composition exhibits a flexural strength of about 100 MPa to about 500 MPa, determined at 23° C. according to ISO Test No. 178:2019.

10. The haptic actuator of claim 1 , wherein the polymer composition comprises a polymer matrix having reinforcing fibers dispersed therein.

11. The haptic actuator of claim 10, wherein the polymer matrix contains a first liquid crystal polymer that includes repeat units derived from 4-hydroxybenzoic acid.

12. The haptic actuator of claim 11 , wherein the first liquid crystal polymer further contains repeat units derived from terephthalic acid, isophthalic acid, hydroquinone, and 4,4′-biphenol.

13. The haptic actuator of claim 12, wherein the molar amount of 4,4'-biphenol is greater than the molar amount of hydroquinone and / or the molar amount of terephthalic acid is greater than the molar amount of isophthalic acid.

14. The haptic actuator of claim 13 , wherein the polymer matrix further comprises a second liquid crystal polymer.

15. The haptic actuator of claim 14, wherein the second liquid crystal polymer includes units derived from 6-hydroxy-2-naphthoic acid.

16. The haptic actuator of claim 15, wherein the second liquid crystal polymer contains units derived from 6-hydroxy-2-naphthoic acid in an amount of about 10 mol % to about 40 mol %.

17. 17. The haptic actuator of claim 16, wherein the first liquid crystal polymer comprises about 50 wt.% to about 95 wt.% of the polymer matrix and the second liquid crystal polymer comprises about 5 wt.% to about 50 wt.% of the polymer matrix.

18. 11. The haptic actuator of claim 10, wherein the polymer matrix contains at least one high naphthenic liquid crystal polymer that includes repeat units derived from 6-hydroxy-2-naphthoic acid in an amount of about 10 mol % to about 40 mol %.

19. 20. The haptic actuator of claim 18, wherein the high naphthenic liquid crystalline polymer comprises about 50 wt. % or more of a total amount of liquid crystalline polymer in the composition.

20. The haptic actuator of claim 10 , wherein the reinforcing fibers include glass fibers.

21. The haptic actuator of claim 10 , wherein the reinforcing fibers include carbon fibers.

22. The haptic actuator of claim 10 , wherein the reinforcing fibers include carbon fibers and glass fibers.

23. 23. The haptic actuator of claim 22, wherein a ratio of glass fibers to carbon fibers by weight is from about 1:10 to about 25:

1.

24. The haptic actuator of claim 10, wherein the reinforcing fibers comprise between about 10 wt. % and about 70 wt. % of the composition.

25. The haptic actuator of claim 1 , wherein at least a portion of the housing contains the polymer composition.

26. An electronic device comprising the haptic actuator of claim 1 .

27. 27. The electronic device of claim 26, wherein the device is a mobile phone, a portable computer, a tablet, or a watch.

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