Patent Publication Number: US-2023165150-A1

Title: Piezoelectric haptic structure

Description:
RELATED APPLICATIONS 
     This application claims priority to Taiwanese Application Serial Number 110143250 filed Nov. 19, 2021, which is herein incorporated by reference. 
     BACKGROUND 
     Technical Field 
     The present disclosure relates to piezoelectric haptic structures. More particularly, the present disclosure relates to piezoelectric haptic structures applied to in-mold electronics (IME). 
     Description of Related Art 
     With the continuous improvement of the living standards nowadays, application of electronic products has become an indispensable part of life. Among different choices, the electronic products with touch function have become more and more popular. Correspondingly, with the rapid advancement of technology, the demand and expectation of people to the electronic products has also been increasing. 
     For example, in order to allow users to have a deeper experience when touching electronic products, the technology of interaction between human and computer of haptic feedback has also become more and more popular. Through the technology of haptic feedback, users can have a more precise and clear interaction when using electronic products. 
     SUMMARY 
     A technical aspect of the present disclosure is to provide a piezoelectric haptic structure, which can achieve a good effect of haptic feedback. 
     According to an embodiment of the present disclosure, a piezoelectric haptic structure includes a thin film, a structural plate and a piezoelectric actuator. The thin film is stacked on the structural plate. The structural plate includes a plate body, a vibrating portion and an elastic portion. The plate body has an inner wall. The inner wall defines a space. The vibrating portion is located in the space and is away from the inner wall. The vibrating portion has an outer wall. The outer wall and the inner wall define a gap therebetween. The elastic portion is elastically connected between the outer wall and the inner wall. The elastic portion seals the gap. The piezoelectric actuator is sandwiched between the thin film and the vibrating portion. 
     In one or more embodiments of the present disclosure, the elastic portion completely surrounds the vibrating portion. 
     In one or more embodiments of the present disclosure, the elastic portion abuts against the thin film. 
     In one or more embodiments of the present disclosure, the vibrating portion has a first thickness. The plate body has a second thickness. The elastic portion has a third thickness. The third thickness is less than the first thickness and the second thickness. 
     In one or more embodiments of the present disclosure, the outer wall and the inner wall are separated from each other by at least one distance. The elastic portion has a length extending between the outer wall and the inner wall. The length is equal to the distance. 
     In one or more embodiments of the present disclosure, the outer wall and the inner wall are separated from each other by a distance. The elastic portion has a length extending between the outer wall and the inner wall. The length is larger than the distance. 
     In one or more embodiments of the present disclosure, the elastic portion has at least one curved part located between the outer wall and the inner wall. 
     In one or more embodiments of the present disclosure, a first material of the elastic portion is the same as a second material of the plate body and the vibrating portion. 
     In one or more embodiments of the present disclosure, a first material of the elastic portion is different from a second material of the plate body and the vibrating portion. 
     In one or more embodiments of the present disclosure, the piezoelectric haptic structure further includes a plastic frame. The plastic frame is disposed on a side of the thin film facing to the elastic portion. The plastic frame at least partially surrounds the piezoelectric actuator. 
     The above-mentioned embodiments of the present disclosure have at least the following advantages: 
     (1) Since the position of the vibrating portion corresponds to the pressing zone on the thin film, and the elastic portion is elastically connected between the outer wall of the vibrating portion and the inner wall of the plate body, when the piezoelectric actuator vibrates, the elastic portion carries out reciprocally elastic deformations with regard to the vibration of the piezoelectric actuator. Thus, the vibrating portion can significantly vibrate relative to the plate body, such that the user can clearly feel vibration of the vibrating portion together with the piezoelectric actuator and know that the pressing on the pressing zone is properly completed. In this way, the piezoelectric haptic structure can achieve a good effect of haptic feedback. 
     (2) Since the structure of the piezoelectric haptic structure is simple, and the quantity of the components involved is small, the manufacturing time and the production cost of the piezoelectric haptic structure can be effectively reduced. 
     (3) Since the elastic portion of the structural plate can have at least one curved part located between the outer wall and the inner wall, the buffering effect of the vibration of the vibrating portion and the thin film relative to the plate body is enhanced. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosure can be more fully understood by reading the following detailed description of the embodiments, with reference made to the accompanying drawings as follows: 
         FIG.  1    is a schematic top view of a piezoelectric haptic structure according to an embodiment of the present disclosure; 
         FIG.  2    is a schematic bottom view of the piezoelectric haptic structure of  FIG.  1   ; 
         FIG.  3    is a cross-sectional view along the sectional line A-A of  FIG.  1   ; 
         FIG.  4    is a cross-sectional view of a piezoelectric haptic structure according to another embodiment of the present disclosure; 
         FIG.  5    is a cross-sectional view of a piezoelectric haptic structure according to a further embodiment of the present disclosure; 
         FIG.  6    is a cross-sectional view of a piezoelectric haptic structure according to another embodiment of the present disclosure; 
         FIG.  7    is a cross-sectional view of a piezoelectric haptic structure according to a further embodiment of the present disclosure; 
         FIG.  8    is a cross-sectional view of a piezoelectric haptic structure according to another embodiment of the present disclosure; 
         FIG.  9    is a bottom view of the piezoelectric haptic structure of  FIG.  8   , in which the structural plate is omitted; 
         FIG.  10    is a bottom view of a piezoelectric haptic structure according to another embodiment of the present disclosure, in which the structural plate is omitted; 
         FIG.  11    is a bottom view of a piezoelectric haptic structure according to a further embodiment of the present disclosure, in which the structural plate is omitted; and 
         FIG.  12    is a bottom view of a piezoelectric haptic structure according to another embodiment of the present disclosure, in which the structural plate is omitted. 
     
    
    
     DETAILED DESCRIPTION 
     Drawings will be used below to disclose embodiments of the present disclosure. For the sake of clear illustration, many practical details will be explained together in the description below. However, it is appreciated that the practical details should not be used to limit the claimed scope. In other words, in some embodiments of the present disclosure, the practical details are not essential. Moreover, for the sake of drawing simplification, some customary structures and elements in the drawings will be schematically shown in a simplified way. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts. 
     Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meanings as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein. 
     Reference is made to  FIGS.  1 - 3   .  FIG.  1    is a schematic top view of a piezoelectric haptic structure  100  according to an embodiment of the present disclosure.  FIG.  2    is a schematic bottom view of the piezoelectric haptic structure  100  of  FIG.  1   .  FIG.  3    is a cross-sectional view along the sectional line A-A of  FIG.  1   . In this embodiment, as shown in  FIGS.  1 - 3   , a piezoelectric haptic structure  100  includes a thin film  110 , a structural plate  120  and a piezoelectric actuator  130 . The thin film  110  is stacked on the structural plate  120 . The thin film  110  defines a pressing zone PZ for a user to press thereon. The structural plate  120  includes a plate body  121 , a vibrating portion  123  and an elastic portion  125 . The plate body  121  has an inner wall  122 . The inner wall  122  surrounds and defines a space SP. The vibrating portion  123  is located in the space SP and is away from the inner wall  122 . This means the vibrating portion  123  does not directly contact with the plate body  121 . A position of the vibrating portion  123  corresponds to the pressing zone PZ on the thin film  110 . The vibrating portion  123  of the structural plate  120  has an outer wall  124 . The outer wall  124  of the vibrating portion  123  and the inner wall  122  of the plate body  121  define a gap GP therebetween. The elastic portion  125  is elastically connected between the outer wall  124  and the inner wall  122 . The elastic portion  125  seals the gap GP. To be specific, the piezoelectric actuator  130  is sandwiched between the thin film  110  and the vibrating portion  123 . In practical applications, the piezoelectric haptic structure  100  is applied to in-mold electronics (IME) (not shown). For example, the piezoelectric haptic structure  100  can be a part of an in-mold electronic, and the thin film  110  is a surface of the in-mold electronic. For the sake of drawing simplification, the cables/electrodes connected to the piezoelectric actuator  130  are not shown in  FIGS.  1 - 3    and other figures as described below. 
     When a user presses on the pressing zone PZ on the thin film  110 , the piezoelectric actuator  130  is actuated, and the piezoelectric actuator  130  converts the input electric energy into mechanical kinetic energy. For example, the piezoelectric actuator  130  generates vibration after being actuated. As mentioned above, since the position of the vibrating portion  123  corresponds to the pressing zone PZ on the thin film  110 , and the piezoelectric actuator  130  is sandwiched between the thin film  110  and the vibrating portion  123 , the position of the piezoelectric actuator  130  also corresponds to the pressing zone PZ. In addition, since the elastic portion  125  is elastically connected between the outer wall  124  of the vibrating portion  123  and the inner wall  122  of the plate body  121 , when the piezoelectric actuator  130  vibrates, the elastic portion  125  carries out reciprocally elastic deformations with regard to the vibration of the piezoelectric actuator  130 . Thus, the vibrating portion  123  can significantly vibrate relative to the plate body  121  and the loss of kinetic energy of the vibrating portion  123  can be reduced, such that the user can clearly feel vibration of the vibrating portion  123  together with the piezoelectric actuator  130  and know that the pressing on the pressing zone PZ is properly completed. In this way, the piezoelectric haptic structure  100  can achieve a good effect of haptic feedback. 
     It is worth to note that, the structure of the piezoelectric haptic structure  100  is simple, and the quantity of the components involved is small. Thus, the manufacturing time and the production cost of the piezoelectric haptic structure  100  can be effectively reduced. 
     In addition, structurally speaking, as shown in  FIG.  2   , since the elastic portion  125  of the structural plate  120  completely surrounds the vibrating portion  123 , the vibration of the vibrating portion  123  relative to the plate body  121  becomes stable. Thus, the piezoelectric haptic structure  100  can achieve a good effect of haptic feedback. 
     Moreover, as shown in  FIG.  3   , the elastic portion  125  of the structural plate  120  abuts against the thin film  110 . Thus, the overall strength of the structural plate  120  and the thin film  110  is enhanced. 
     Furthermore, as shown in  FIG.  3   , the vibrating portion  123  of the structural plate  120  has a first thickness TK 1 . The plate body  121  of the structural plate  120  has a second thickness TK 2 . The elastic portion  125  of the structural plate  120  has a third thickness TK 3 . In this embodiment, the third thickness TK 3  of the elastic portion  125  is less than the first thickness TK 1  of the vibrating portion  123 , and the third thickness TK 3  of the elastic portion  125  is also less than the second thickness TK 2  of the plate body  121 . In practice, for example, the first thickness TK 1  of the vibrating portion  123  can be within 0.5-5.0 mm. The second thickness TK 2  of the plate body  121  can be larger than or equal to the first thickness TK 1  of the vibrating portion  123 . The third thickness TK 3  of the elastic portion  125  can be within 0.0-2.0 mm. However, this does not intend to limit the present disclosure. 
     In practical applications, the structural plate  120  can be formed from injection molding. Therefore, the vibrating portion  123 , the elastic portion  125  and the plate body  121  can be an integrally formed structure, and the material of the elastic portion  125  is the same as the material of the plate body  121  and the vibrating portion  123 . For example, during the process of the injection molding, a user forms an avoiding zone AZ between the vibrating portion  123  and the plate body  121 . The avoiding zone AZ is substantially the space SP within which formation of the plastic does not occur during the process of the injection molding. In this way, the elastic portion  125  with thickness less than the vibrating portion  123  and the plate body  121  can be formed between the vibrating portion  123  and the plate body  121 . 
     According to the actual situations, the outer wall  124  of the vibrating portion  123  and the inner wall  122  of the plate body  121  can be surfaces parallel with each other or surfaces inclines with each other. However, this does not intend to limit the present disclosure. To be specific, as shown in  FIG.  3   , the outer wall  124  of the vibrating portion  123  and the inner wall  122  of the plate body  121  are separated from each other by a distance DT. The elastic portion  125  has a length LG extending between the outer wall  124  and the inner wall  122 . In this embodiment, the length LG of the elastic portion  125  is equal to the distance DT separated between the outer wall  124  of the vibrating portion  123  and the inner wall  122  of the plate body  121 . In other words, the elastic portion  125  is horizontally disposed relative to the vibrating portion  123  and the plate body  121  and elastically connected between the vibrating portion  123  and the plate body  121 . To be specific, the distance DT separated between the outer wall  124  of the vibrating portion  123  and the inner wall  122  of the plate body  121  is equal to the width of the gap GP between the outer wall  124  of the vibrating portion  123  and the inner wall  122  of the plate body  121 . In practice, for example, the distance DT can be larger than 0.5 mm. However, this does not intend to limit the present disclosure. 
     Reference is made to  FIG.  4   .  FIG.  4    is a cross-sectional view of a piezoelectric haptic structure  100  according to another embodiment of the present disclosure. In this embodiment, as shown in  FIG.  4   , according to different characteristics of the vibration of the vibrating portion  123  relative to the plate body  121 , for example, for the sake of enhancement of a buffering effect of the vibration of the vibrating portion  123  and the thin film  110  relative to the plate body  121 , the elastic portion  125  of the structural plate  120  has at least one curved part  126  located between the outer wall  124  and the inner wall  122 . Therefore, the length LG of the elastic portion  125  extending between the outer wall  124  of the vibrating portion  123  and the inner wall  122  of the plate body  121  is larger than the distance DT separated between the outer wall  124  and the inner wall  122 . Moreover, as shown in  FIG.  4   , the portion of the thin film  110  connecting with the curved part  126  is also curved or bent with the curved part  126 . 
     Reference is made to  FIGS.  5 - 6   .  FIG.  5    is a cross-sectional view of a piezoelectric haptic structure  100  according to a further embodiment of the present disclosure.  FIG.  6    is a cross-sectional view of a piezoelectric haptic structure  100  according to another embodiment of the present disclosure. In this embodiment, as shown in  FIGS.  5 - 6   , according to different characteristics of the vibration of the vibrating portion  123  relative to the plate body  121 , for example, for the sake of enhancement of a buffering effect of the vibration of the vibrating portion  123  and the thin film  110  relative to the plate body  121 , the elastic portion  125  of the structural plate  120  has a plurality of curved parts  126  located between the outer wall  124  and the inner wall  122 . Moreover, the length LG of the elastic portion  125  extending between the vibrating portion  123  and the plate body  121  is larger than the distance DT separated between the outer wall  124  and the inner wall  122 . For example, as shown in  FIG.  5   , the elastic portion  125  has two curved parts  126  located between the outer wall  124  and the inner wall  122 . The curved part  126  relatively near to the vibrating portion  123  protrudes towards a side of the thin film  110 , while the curved part  126  relatively near to the plate body  121  protrudes towards a side away from the thin film  110 . On the other hand, for example, as shown in  FIG.  6   , the elastic portion  125  also has two curved parts  126  located between the outer wall  124  and the inner wall  122 . The curved part  126  relatively near to the vibrating portion  123  protrudes towards a side away from the thin film  110 , while the curved part  126  relatively near to the plate body  121  protrudes towards a side of the thin film  110 . 
     Reference is made to  FIG.  7   .  FIG.  7    is a cross-sectional view of a piezoelectric haptic structure  100  according to a further embodiment of the present disclosure. For example, in this embodiment, as shown in  FIG.  7   , in order to enhance the buffering effect of vibration of the vibrating portion  123  and the thin film  110  relative to the plate body  121  and also reinforce the overall stiffness of the elastic portion  125  and the thin film  110 , the elastic portion  125  of the structural plate  120  can be flexible plastic. This means the material of the elastic portion  125  is different from the material of the plate body  121  and the vibrating portion  123 . In other words, according to the actual situations, the elastic portion  125  is not integrally formed with the vibrating portion  123  and the plate body  121 . 
     Reference is made to  FIGS.  8 - 9   .  FIG.  8    is a cross-sectional view of a piezoelectric haptic structure  100  according to another embodiment of the present disclosure.  FIG.  9    is a bottom view of the piezoelectric haptic structure  100  of  FIG.  8   , in which the structural plate  120  is omitted. In this embodiment, as shown in  FIGS.  8 - 9   , in order to enhance the buffering effect of vibration of the vibrating portion  123  and the thin film  110  relative to the plate body  121 , the piezoelectric haptic structure  100  further includes a plastic frame  140 . The plastic frame  140  is disposed on a side of the thin film  110  facing to the elastic portion  125 . The plastic frame  140  at least partially surrounds the piezoelectric actuator  130 . For example, the plastic frame  140  is formed form soft glue. To be specific, in the manufacturing process of the piezoelectric haptic structure  100 , after the piezoelectric actuator  130  and the plastic frame  140  are respectively disposed on the thin film  110 , the structural plate  120  is disposed on the thin film  110  by injection molding, and the piezoelectric actuator  130  and the plastic frame  140  are respectively sandwiched between the thin film  110  and the structural plate  120 , while the vibrating portion  123  and the elastic portion  125  respectively correspond to the piezoelectric actuator  130  and the plastic frame  140 . In this embodiment, the plastic frame  140  and the piezoelectric actuator  130  are separated from each other. This means plastic frame  140  and the piezoelectric actuator  130  are not in contact with each other. 
     Reference is made to  FIG.  10   .  FIG.  10    is a bottom view of a piezoelectric haptic structure  100  according to another embodiment of the present disclosure, in which the structural plate  120  is omitted. In this embodiment, as shown in  FIG.  10   , according to the actual situations, the plastic frame  140  surrounds and mutually connects with the piezoelectric actuator  130 . 
     Reference is made to  FIGS.  11 - 12   .  FIG.  11    is a bottom view of a piezoelectric haptic structure  100  according to a further embodiment of the present disclosure, in which the structural plate  120  is omitted.  FIG.  12    is a bottom view of a piezoelectric haptic structure  100  according to another embodiment of the present disclosure, in which the structural plate  120  is omitted. In this embodiment, as shown in  FIGS.  11 - 12   , the plastic frame  140  surrounds the piezoelectric actuator  130  and is separated from the piezoelectric actuator  130 . This means the plastic frame  140  and the piezoelectric actuator  130  are not in contact with each other. For example, as shown in  FIG.  11   , the plastic frame  140  includes two C-shaped frames  141 . The opening of each of the C-shaped frames  141  faces to each other. The C-shaped frames  141  are separated from each other and surround the piezoelectric actuator  130 . On the other hand, for example, as shown in  FIG.  12   , the plastic frame  140  includes four rod-shaped frames  142 . The rod-shaped frames  142  are separated from each other and surround the piezoelectric actuator  130  in the form of a rectangular arrangement. 
     In conclusion, the aforementioned embodiments of the present disclosure have at least the following advantages: 
     (1) Since the position of the vibrating portion corresponds to the pressing zone on the thin film, and the elastic portion is elastically connected between the outer wall of the vibrating portion and the inner wall of the plate body, when the piezoelectric actuator vibrates, the elastic portion carries out reciprocally elastic deformations with regard to the vibration of the piezoelectric actuator. Thus, the vibrating portion can significantly vibrate relative to the plate body, such that the user can clearly feel vibration of the vibrating portion together with the piezoelectric actuator and know that the pressing on the pressing zone is properly completed. In this way, the piezoelectric haptic structure can achieve a good effect of haptic feedback. 
     (2) Since the structure of the piezoelectric haptic structure is simple, and the quantity of the components involved is small, the manufacturing time and the production cost of the piezoelectric haptic structure can be effectively reduced. 
     (3) Since the elastic portion of the structural plate can have at least one curved part located between the outer wall and the inner wall, the buffering effect of the vibration of the vibrating portion and the thin film relative to the plate body is enhanced. 
     Although the present disclosure has been described in considerable detail with reference to certain embodiments thereof, other embodiments are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the embodiments contained herein. 
     It will be apparent to the person having ordinary skill in the art that various modifications and variations can be made to the structure of the present disclosure without departing from the scope or spirit of the present disclosure. In view of the foregoing, it is intended that the present disclosure cover modifications and variations of the present disclosure provided they fall within the scope of the following claims.