Patent Publication Number: US-2023142874-A1

Title: Mobile terminal

Description:
This application claims priority to Chinese Patent Application No. 202010345451.4, filed with the China National Intellectual Property Administration on Apr. 27, 2020 and entitled “MOBILE TERMINAL”, which is incorporated herein by reference in its entirety. 
     TECHNICAL FIELD 
     This application pertains to the field of audio device technologies, and in particular, to a mobile terminal. 
     BACKGROUND 
     A terminal device such as a mobile phone, a tablet computer, or a notebook computer is equipped with a speaker. The speaker includes a box and a sound generation unit disposed in the box. When the speaker is applied to the terminal device, the box of the speaker communicates with an external environment through a sound hole. 
     In the conventional technology, the speaker communicates with internal space of the terminal device. Therefore, when a housing of the terminal device is pressed and a size of the internal space of the terminal device changes, atmospheric pressure in front space and rear space of a diaphragm in the box of the speaker changes correspondingly. In this case, vibration frequency of air in the sound generation unit is disturbed. Consequently, the diaphragm moves up and down to generate noise, and may touch a magnetic part in the sound generation unit and be damaged. In addition, there is relatively significant sibilance and a relatively significant metal sound when the speaker generates a sound. 
     SUMMARY 
     Embodiments of this application are intended to provide a mobile terminal, to resolve a technical problem, in the conventional technology, that when a housing of the mobile terminal is pressed and a size of internal space changes, there is relatively significant sibilance and a relatively significant metal sound when a speaker in the mobile terminal generates a sound. 
     To achieve the foregoing objective, technical solutions used in this application are as follows: A mobile terminal is provided. The mobile terminal includes a housing and a speaker disposed in the housing. The speaker includes a box and a sound generation unit configured to generate a sound. The box includes a first cover body and a second cover body and a cover plate that are located on the first cover body. The sound generation unit is disposed in the first cover body, and a first cavity is formed between the sound generation unit and an inner bottom wall of the first cover body. A sound hole that communicates with an external environment of the housing is disposed in the first cavity. A second cavity is formed between the sound generation unit and an inner top wall of the second cover body. The sound generation unit includes a diaphragm configured to generate a sound through vibration, and two opposite surfaces of the diaphragm respectively correspond to the first cavity and the second cavity. A resonant cavity is formed in the first cover body, the resonant cavity communicates with the first cavity, and a through hole is disposed on a side that is of the resonant cavity and that faces the second cavity. The cover plate covers the through hole, and a microhole that communicates with the second cavity is disposed on the cover plate. 
     In the mobile terminal provided in this embodiment of this application, the speaker is disposed in the housing of the mobile terminal, the first cavity is formed between the sound generation unit in the speaker and the first cover body of the box, the second cavity is formed between the sound generation unit and the second cover body of the box, the sound generated by the sound generation unit is output to the external environment through the sound hole, the first cavity communicates with the second cavity through the resonant cavity, the cover plate on which the microhole is disposed is disposed at the through hole of the resonant cavity, and the resonant cavity communicates with the second cavity through the microhole. In this way, balance of atmospheric pressure can be maintained for the first cavity and the second cavity of the box through the resonant cavity, so that the diaphragm in the sound generation unit vibrates normally. The second cavity communicates with the resonant cavity through the microhole, and a relatively small volume of airflow can pass through the microhole. Therefore, circulation of airflow in the second cavity is reduced. In this way, when the box is pressed or returns to a normal state from a pressed state, the airflow enters and exits the second cavity through the microhole, and therefore atmospheric pressure in the second cavity does not change significantly. The first cavity communicates with the external environment through the sound hole, and therefore atmospheric pressure in the first cavity also does not change significantly. Therefore, when the diaphragm in the sound generation unit vibrates, an amplitude of the diaphragm can be kept within a proper range. In this way, the diaphragm does not collide with a magnetic part in the sound generation unit during vibration, and therefore sibilance and a metal sound that exist when the speaker generates a sound, especially when a high-frequency sound is generated, are effectively suppressed, thereby improving quality of the high-frequency sound generated by the speaker. 
     Optionally, an enclosure frame is disposed in the first cover body, the sound generation unit is mounted to the enclosure frame, a first region is formed at intervals between an inner sidewall of the first cover body and an outer sidewall of the enclosure frame, a block object is disposed in the first region, and the resonant cavity is disposed in the block object. The first region is formed at intervals between an inner wall of the first cover body and an outer wall of the enclosure frame, and the resonant cavity is disposed in the block object in the first region, so that assembly space in the box is fully used, and the resonant cavity is independently disposed with respect to the first cavity and the second cavity. 
     Optionally, the box further includes a multihole object, and the multihole object is disposed on the cover plate and covers the microhole. The multihole object is disposed on the cover plate, and the multihole object covers the microhole, so that a combination of the multihole object and the microhole is used to further limit a volume of airflow that enters and exits the second cavity, so as to further stabilize the atmospheric pressure in the second cavity. 
     Optionally, the multihole object is attached to a side that is of the cover plate and that faces or faces away from the resonant cavity. 
     Optionally, a concave cavity is disposed on a side that is of the cover plate and that faces or faces away from the resonant cavity, the multihole object is mounted in the concave cavity, and the microhole is disposed at a bottom of the concave cavity. The concave cavity is disposed on the cover plate, and the multihole object is mounted in the concave cavity, to improve connection stability between the multihole object and the cover plate, and to facilitate fast removal and replacement of the multihole object with respect to the cover plate. 
     Optionally, a gap is formed between an outer edge of the multihole object and a cavity wall of the concave cavity. 
     Optionally, the multihole object is a mesh, and the mesh is made of a nonwoven fabric; or 
     the mesh is formed by stacking a nonwoven fabric and degreased gauze. The multihole object is specifically set as a mesh. In this way, because of relatively good permeability of the mesh and the fact that holes on the mesh are relatively evenly and finely distributed, the mesh cooperates with the microhole, to precisely adjust the volume of airflow that enters and exits the second cavity. 
     Optionally, the box further includes a polyethylene-terephthalate (PET) film, the PET film covers a side that is of the cover plate and that faces the resonant cavity, and a first breather region that communicates with the resonant cavity is formed between the PET film and the cover plate. 
     Optionally, the box further includes a PET film, the PET film covers a side that is of the cover plate and that faces away from the resonant cavity, and a second breather region that communicates with the second cavity is formed between the PET film and the cover plate. 
     Optionally, the box further includes a PET film, the PET film covers a side that is of the cover plate and that faces or faces away from the resonant cavity, and several breather holes are disposed on the PET film. 
     Optionally, a connection channel is disposed on a cavity wall of the first cavity, the connection channel penetrates through the enclosure frame and the block object, and communicates with the resonant cavity, and a cross-sectional area of the connection channel is greater than an opening area of the microhole. It is set that the cross-sectional area of the connection channel is greater than the opening area of the microhole, so that a speed at which the airflow enters the resonant cavity from the first cavity is greater than a speed at which the airflow enters the second cavity from the resonant cavity, to reduce a speed at which the airflow is exchanged between the first cavity and the second cavity. 
     Optionally, the cross-sectional area of the connection channel is 2 to 15 times the opening area of the microhole. In this way, the speed at which the airflow is exchanged between the first cavity and the second cavity is precisely controlled. 
     Optionally, an aperture of the microhole ranges from 0.5 mm to 2 mm. In this way, the volume of airflow that enters and exits the second cavity is effectively controlled. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       To describe technical solutions in embodiments of this application or the conventional technology more clearly, the following briefly introduces the accompanying drawings required for describing embodiments or the conventional technology. It is clear that the accompanying drawings in the following descriptions show some embodiments of this application, and a person of ordinary skill in the art may still derive other drawings from these accompanying drawings without creative efforts. 
         FIG.  1    is an accompanying drawing in the conventional technology; 
         FIG.  2    is a schematic diagram of structures of a mobile terminal and a speaker according to an embodiment of this application; 
         FIG.  3    is a schematic diagram  1  of a cutaway structure of a speaker according to an embodiment of this application; 
         FIG.  4    is a schematic diagram  2  of a cutaway structure of a speaker according to an embodiment of this application; 
         FIG.  5    is a schematic diagram  3  of a cutaway structure of a speaker according to an embodiment of this application; 
         FIG.  6    is a schematic diagram  4  of a cutaway structure of a speaker according to an embodiment of this application; 
         FIG.  7    is a schematic diagram of an exploded structure of a speaker according to an embodiment of this application; 
         FIG.  8    is a schematic diagram  1  of a partial structure of a speaker according to an embodiment of this application; 
         FIG.  9    is a schematic diagram  2  of a partial structure of a speaker according to an embodiment of this application; 
         FIG.  10    is a cutaway drawing of a cross section of a mesh of a speaker according to an embodiment of this application; and 
         FIG.  11    is a schematic diagram  3  of a partial structure of a speaker according to an embodiment of this application. 
     
    
    
     REFERENCE NUMERALS IN THE DRAWINGS 
     
         
         
           
               10 : Speaker;  11 : Box;  12 : Sound generation unit; 
               13 : Cover plate;  14 : Multihole object;  15 : PET film; 
               16 : First region;  17 : Block object;  18 : Connection channel; 
               20 : Mobile terminal;  21 : Housing;  22 : Notch; 
               30 : Sound generation apparatus;  31 : Air discharge hole;  111 : First cavity; 
               112 : Second cavity;  113 : Sound hole;  114 : Resonant cavity; 
               115 : Microhole;  116 : Through hole;  117 : First cover body; 
               118 : Second cover body;  119 : Enclosure frame;  121 : Frame; 
               122 : Voice coil;  123 : Diaphragm;  124 : Washer; 
               125 : Magnetic part;  126 : Iron core;  127 : Flexible circuit board; 
               131 : Concave cavity;  141 : Mesh;  142 : Nonwoven fabric; 
               143 : Degreased gauze layer;  151 : First breather region;  152 : Second breather region; and 
               153 : Breather hole. 
           
         
       
    
     DESCRIPTION OF EMBODIMENTS 
     The embodiments of this application are described below in detail. Examples of the embodiments are shown in the accompanying drawings, and same or similar reference numerals represent same or similar elements or elements with same or similar functions. The embodiments described below with reference to  FIG.  1    to  FIG.  11    are examples, are intended to explain this application, and should not be understood as a limitation on this application. 
     In the descriptions of this application, it should be understood that directions or positional relationships indicated by terms such as “length”, “width”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, and “outside” are directions or positional relationships shown based on the accompanying drawings, are merely used for facilitating description of this application and for description simplicity, and do not indicate or imply that an indicated apparatus or element needs to have a specific direction or needs to be constructed and operated in a specific direction. Therefore, this should not be understood as a limitation on this application. 
     In addition, the terms “first” and “second” are merely intended for a purpose of description, and shall not be understood as an indication or implication of relative importance or implicit indication of the number of indicated technical features. Therefore, a feature limited by “first” or “second” may explicitly indicate or implicitly include one or more such features. In the descriptions of this application, unless otherwise expressly and specifically limited, “a plurality of” means two or more. 
     In this application, unless otherwise expressly specified and limited, terms such as “mounting”, “connected”, “connection”, and “fastening” should be understood in a broad sense. For example, there may be a fixed connection, a detachable connection, or an integrated connection; there may be a mechanical connection or an electrical connection; or there may be a direct connection, an indirect connection established by using an intermediate medium, or a connection inside two elements or an interaction relationship between two elements. A person of ordinary skill in the art may understand specific meanings of the foregoing terms in this application based on a specific situation. 
     For ease of understanding, technical terms in this application are first explained and described below. 
     A speaker is an energy conversion device that converts an electrical signal into a sound signal. The speaker electrically drives a voice coil in the speaker to vibrate, and drives a diaphragm to vibrate, so that air around the speaker resonates and generates a sound. 
     PET (Polyethylene-terephthalate) is a thermoplastic polyester including polyethylene terephthalate. PET is a polycondensate of terephthalic acid and ethylene glycol, and is commonly known as polyester resin in the industry. 
     A nonwoven fabric is made of an orientated or random fiber, and has advantages such as moisture-proof, breathable, flexible, lightweight, non-combustible, and easy to decompose. 
     Degreased gauze refers to pure cotton gauze obtained after degreasing treatment. 
       FIG.  1    is a schematic diagram of a structure of a sound generation apparatus  30  in the conventional technology. It is shown in  FIG.  1    that an air discharge hole  31  is disposed on a housing of the sound generation apparatus  30 . When the sound generation apparatus  30  is assembled into an external terminal device, the air discharge hole  31  of the sound generation apparatus communicates with internal space of the terminal device. 
     As shown in  FIG.  2   , an embodiment of this application provides a mobile terminal  20 . The mobile terminal  20  includes a housing  21  and a speaker  10  disposed in the housing  21 . The mobile terminal  20  includes but is not limited to a mobile phone, a tablet computer, a notebook computer, an ultra-mobile personal computer (ultra-mobile personal computer, UMPC), a netbook, a personal digital assistant (personal digital assistant, PDA), or the like. In particular, the mobile terminal  20  has a relatively high waterproof sealing property. A specific type of the mobile terminal  20  is not limited in this embodiment of this application. 
     Referring to  FIG.  2    and  FIG.  3   , the speaker  10  includes a box  11  and a sound generation unit  12  configured to generate a sound. The box  11  includes a first cover body  117  and a second cover body  118  and a cover plate  13  that are located on the first cover body  117 . The sound generation unit  12  is disposed in the first cover body  117 , and a first cavity  111  is formed between the sound generation unit  12  and an inner bottom wall of the first cover body  117 . A sound hole  113  that communicates with an external environment of the housing  21  is disposed in the first cavity  111 . A notch  22  is disposed at a position that is of the housing  21  of the mobile terminal  20  and that corresponds to the sound hole  113  of the speaker  10 , so that a sound generated by the speaker  10  is conducted to the external environment. A second cavity  112  is formed between the sound generation unit  12  and an inner top wall of the second cover body  118 . 
     In this embodiment of this application, the sound generation unit  12  may be a dome sound generation unit, a reed sound generation unit, a cone sound generation unit, or the like. Referring to  FIG.  3    to  FIG.  5   , basic components of the sound generation unit  12  may include a frame  121 , a voice coil  122  disposed in the frame  121 , and a diaphragm  123  that surrounds a periphery of the voice coil  122  and that is exposed to the frame  121 . A washer  124  and a magnetic part  125  are sequentially disposed below the diaphragm  123 , and an iron core  126  is disposed below the magnetic part  125 . Referring to  FIG.  7   , a flexible circuit board  127  configured to be electrically connected to a related electronic device in the mobile terminal  20  is further led out from the speaker  10 . 
     Referring to  FIG.  2    to  FIG.  4   , two opposite surfaces of the diaphragm  123  in the sound generation unit  12  respectively correspond to the first cavity  111  and the second cavity  112 . A resonant cavity  114  is formed in the first cover body  117 , the resonant cavity  114  communicates with the first cavity  111 , and a through hole  116  is disposed on a side that is of the resonant cavity  114  and that faces the second cavity  112 . The cover plate  13  covers the through hole  116 , and a microhole  115  that communicates with the second cavity  112  is disposed on the cover plate  13 . In this embodiment, a surface that is of the diaphragm  123  and that faces away from the magnetic part  125  is disposed to correspond to the first cavity  111 , and a surface that is of the diaphragm  123  and that faces the magnetic part  125  is disposed to correspond to the second cavity  112 . 
     More specifically, in this embodiment of this application, the second cavity  112  of the speaker  10  does not communicate with internal space of the housing  21  of the mobile terminal  20 , which is different from the design, in the conventional technology, in which the air discharge hole  31  that communicates with an inside of the terminal device is disposed on the housing of the sound generation apparatus  30  (as shown in  FIG.  1   ). As shown in  FIG.  2    to  FIG.  4   , the resonant cavity  114  communicates with the second cavity  112  through the microhole  115 . 
     As shown in  FIG.  3   , the speaker  10  provided in this embodiment of this application is further described below. In the speaker  10  provided in this embodiment of this application, the sound generation unit  12  of the speaker  10  is disposed in the box  11 , the first cavity  111  is formed between the sound generation unit  12  and the first cover body  117  of the box  11 , the second cavity  112  is formed between the sound generation unit  12  and the second cover body  118  of the box  11 , the sound generated by the sound generation unit  12  is output to the external environment through the sound hole  113 , the first cavity  111  communicates with the second cavity  112  through the resonant cavity  114 , the cover plate  13  on which the microhole  115  is disposed is disposed at the through hole  116  of the resonant cavity  114 , and the resonant cavity  114  communicates with the second cavity  112  through the microhole  115 . In this way, balance of atmospheric pressure can be maintained for the first cavity  111  and the second cavity  112  of the speaker  10  through the resonant cavity  114 , so that the diaphragm  123  in the sound generation unit  10  vibrates normally. The second cavity  112  communicates with the resonant cavity  114  through the microhole  115 , and a relatively small volume of airflow can pass through the microhole  115 . Therefore, circulation of airflow in the second cavity  112  is reduced. In this way, when the box  11  is pressed or returns to a normal state from a pressed state, the airflow enters and exits the second cavity  112  through the microhole  115 , and therefore atmospheric pressure in the second cavity  112  does not change significantly. The first cavity  111  communicates with the external environment through the sound hole  113 , and therefore atmospheric pressure in the first cavity  111  also does not change significantly. Therefore, when the diaphragm  123  in the sound generation unit  12  vibrates, an amplitude of the diaphragm  123  can be kept within a proper range. In this way, the diaphragm  123  does not collide with the magnetic part  125  in the sound generation unit  12  during vibration, and therefore sibilance and a metal sound that exist when the speaker  10  generates a sound, especially when a high-frequency sound is generated, are effectively suppressed, thereby improving quality of the high-frequency sound generated by the speaker  10 . 
     The through hole  116  is disposed on one side of the resonant cavity  114 , and the microhole  115  is formed on the cover plate  13  that covers the through hole  116 . In this way, when an aperture size of the microhole  115  needs to be adjusted, the cover plate  13  may be removed and replaced with a cover plate  13  that includes a microhole  115  with a corresponding aperture, to flexibly adjust an aperture of the microhole  115 . 
     Optionally, the cover plate  13  may be mounted to the through hole  116 , to improve convenience of removing and replacing the cover plate  13  with respect to the second cavity  112 , or may be bonded to an outer edge of the through hole  116  in a manner such as gluing or hot-melt bonding, to improve assembly stability of the cover plate  13  with respect to the second cavity  112 . 
     Optionally, the microhole  115  may be an irregularly shaped hole such as a round hole, an elliptical hole, or a rectangular hole. A specific hole type of the microhole  115  may be determined based on a volume of to-be-exchanged airflow designed for the second cavity  112 . 
     In some other embodiments of this application, as shown in  FIG.  5    to  FIG.  7   , an enclosure frame  119  is disposed in the first cover body  117 , the sound generation unit  12  is mounted to the enclosure frame  119 , a first region  16  is formed at an interval between an inner wall of the first cover body  117  and an outer wall of the enclosure frame  119 , a block object  17  is disposed in the first region  16 , the resonant cavity  114  is disposed in the block object  17 , and a connection channel  18  penetrates through the enclosure frame  119  and the block object  17 , and communicates with the resonant cavity  114 . 
     Specifically, space between the sound generation unit  12  and the enclosure frame  119  may be sealed through gluing. In this way, the first cavity  111  and the second cavity  112  are isolated and sealed, and glue is used as a buffer between the sound generation unit  12  and the enclosure frame  119 , to eliminate excessive vibration caused due to mutual collision between the sound generation unit  12  and the enclosure frame  119 , so as to improve a sound generation effect of the sound generation unit  12 . 
     The first region  16  is formed at intervals between the inner wall of the first cover body  117  and the outer wall of the enclosure frame  119 , and the resonant cavity  114  is disposed in the block object  17  in the first region  16 , so that assembly space in the box  11  is fully used, and the resonant cavity  114  is independently disposed with respect to the first cavity  111  and the second cavity  112 . 
     Optionally, the block object  17  may be integrally formed with the first cover body  117 , to reduce manufacturing costs of the box  11 . Alternatively, the block object  17  may be independently manufactured and formed, and then mounted to or bonded to the first region  16 . In this way, the block object  17  and the first cover body  117  may not need to be made of a same material. For example, the first cover body  17  may be made of a plastic part, and the block object  17  may be made of a metal part. In addition, the block object may be in a square shape or an irregular shape. A shape of the block object may be determined based on a size and a shape of assembly space available in the first region  16 . 
     In some other embodiments of this application, as shown in  FIG.  3   ,  FIG.  7   , and  FIG.  8   , the box  11  further includes a multihole object  14 , and the multihole object  14  is disposed on the cover plate  13  and covers the microhole  115 . 
     Specifically, the multihole object  14  is disposed on the cover plate  13 , and the multihole object  14  covers the microhole  115 , so that a combination of the multihole object  14  and the microhole  115  is used to further limit a volume of airflow that enters and exits the second cavity  112 , so as to further stabilize the atmospheric pressure in the second cavity  112 . 
     Optionally, the multihole object  14  may be removably disposed on the cover plate  13  by using double-sided adhesive or the like. In this way, multihole objects  14  with different thicknesses may be used through replacement, to further precisely adjust the volume of airflow that enters and exits the second cavity  112 , so as to precisely adjust and control the atmospheric pressure in the second cavity  112 . 
     In some other embodiments of this application, the multihole object  14  is attached to a side that is of the cover plate  13  and that faces or faces away from the resonant cavity  114 . 
     Specifically, the multihole object  14  may be mounted on the side that is of the cover plate  13  and that faces or faces away from the resonant cavity  114  based on a size of assembly space on the side that is of the cover plate  13  and that faces or faces away from the resonant cavity  114 . 
     In some other embodiments of this application, as shown in  FIG.  7    to  FIG.  9   , a concave cavity  131  is disposed on a side that is of the cover plate  13  and that faces or faces away from the resonant cavity  114 , the multihole object  14  is mounted in the concave cavity  131 , and the microhole  115  is disposed at a bottom of the concave cavity  131 . 
     Specifically, the concave cavity  131  is disposed on the cover plate  13 , and the multihole object  14  is mounted in the concave cavity  131 , to improve connection stability between the multihole object  14  and the cover plate  13 , and to facilitate fast removal and replacement of the multihole object  14  with respect to the cover plate  13 . 
     Optionally, the multihole object  14  is bonded to the concave cavity  131 , to improve assembly stability of the multihole object  14  in the concave cavity  131 . In addition, an outer edge of the multihole object  14  may be connected to a cavity wall of the concave cavity  131  or an edge at the bottom of the concave cavity  131  through gluing or by attaching double-sided adhesive, so that when the airflow flows into the multihole object  14  through the microhole  115 , the airflow does not flow out from a gap between the multihole object  14  and the cavity wall of the concave cavity  131 , and most of the airflow flows into the second cavity  112  or the resonant cavity  114  through the multihole object  14 . In this way, utilization of the multihole object  14  is improved, and a function of blocking the airflow by the multihole object  14  is fully used. 
     In some other embodiments of this application, a gap is formed between the outer edge of the multihole object  14  and the cavity wall of the concave cavity  131 . 
     Specifically, a gap is formed between the outer edge of the multihole object  14  and the cavity wall of the concave cavity  131 . In this way, it may be convenient to pull the multihole object  14  out of the concave cavity  131 , so that the multihole object  14  can be quickly removed from the concave cavity  131 , and assembly convenience of the multihole object  14  with respect to the concave cavity  131  is improved. 
     In some other embodiments of this application, the multihole object  14  is a mesh  141 , and the mesh  141  may be made of a nonwoven fabric  142 . 
     Specifically, the multihole object  14  is specifically set as the mesh  141 . In this way, because of relatively good permeability of the mesh  141  and the fact that holes on the mesh  141  are relatively evenly and finely distributed, the mesh  141  cooperates with the microhole  115 , to precisely adjust the volume of airflow that enters and exits the second cavity  112  and to improve smoothness and evenness of the airflow that enters and exits the second cavity  112 . In addition, the mesh  141  is easy to obtain and is manufactured at low costs. Therefore, overall manufacturing costs of the speaker  10  are reduced. 
     The nonwoven fabric  142  has advantages of breathable, flexible, lightweight, and non-toxic. Therefore, the nonwoven fabric  142  can effectively control the volume of airflow that enters and exits the second cavity  112 , and improve environmental friendliness of the speaker  10  in terms of material selection. 
     In some other embodiments of this application, as shown in  FIG.  10   , the mesh  141  may be formed by stacking a nonwoven fabric  142  and a degreased gauze layer  143 . In this way, in addition to the foregoing advantages, the mesh  141  can further effectively prevent a fine impurity in the air from entering and exiting the second cavity  112 , to prevent the fine impurity from flowing freely between the first cavity  111  and the second cavity  112 , so as to prevent the fine impurity from affecting vibration of the diaphragm  123 . Therefore, quality of a sound generated by the speaker  10  is improved. 
     Optionally, the multihole object  14  may alternatively be made of a material such as a sponge in consideration of costs and the like. 
     In some other embodiments of this application, as shown in  FIG.  4   ,  FIG.  5   , and  FIG.  11   , in a manner of replacing the multihole object  14 , the box  11  further includes a PET film. The PET film  15  covers a side that is of the cover plate  13  and that faces the resonant cavity  114 , and a first breather region  152  (as shown in  FIG.  4   ) that communicates with the resonant cavity  114  is formed between the PET film  15  and the cover plate  13 . Alternatively, the PET film  15  covers a side that is of the cover plate  13  and that faces away from the resonant cavity  114 , and a second breather region  151  (as shown in  FIG.  5   ) that communicates with the second cavity  112  is formed between the PET film  15  and the cover plate  13 . 
     Specifically, as shown in  FIG.  4   ,  FIG.  5   , and  FIG.  11   , in this embodiment, the PET film  15  is used to replace the multihole object  14 , and the PET film  15  covers the cover plate  13 . In this way, the airflow that enters and exits the second cavity  112  through the microhole  115  may be blocked by the PET film  15  and enter the resonant cavity  114  through the first breather region  152  or enter the second cavity  112  through the first breather region  151 . The volume of airflow that enters and exits the second cavity  112  may be effectively adjusted by controlling a size of region space of the first breather region  152  or the first breather region  151 . Therefore, costs of adjusting the volume of airflow that enters and exits the second cavity  112  are reduced. The PET film  15  has high impact resistance performance and a non-toxic property, and therefore the PET film  15  can be used stably in the speaker  10  for a long time, and improve environmental friendliness of the speaker  10  in terms of material selection. 
     Optionally, as shown in  FIG.  6   , as an alternative to canceling the design of the first breather region  152  or the first breather region  151 , several breather holes  153  may be directly disposed on the PET film  15 , so that the PET film  15  is breathable, and the airflow that enters and exits the second cavity  112  may directly flow into the second cavity  112  or the resonant cavity  114  through the breather holes  153  after passing through the microhole  115 . In this way, a breathable structure of the PET film  15  can be simplified, to reduce overall manufacturing costs of the speaker  10 . 
     In some other embodiments of this application, as shown in  FIG.  7    to  FIG.  9   , the connection channel  18  is disposed on an inner wall of the enclosure frame  119 , the connection channel  18  communicates with the resonant cavity  114 , and a cross-sectional area of the connection channel  18  is greater than an opening area of the microhole  115 . Specifically, the connection channel  18  may be disposed through mechanical processing, or may be formed during injection molding of the box  11 . 
     It is set that the cross-sectional area of the connection channel  18  is greater than the opening area of the microhole  115 , so that a speed at which the airflow enters the resonant cavity  114  from the first cavity  111  is greater than a speed at which the airflow enters the second cavity  112  from the resonant cavity  114 , to reduce a speed at which the airflow is exchanged between the first cavity  111  and the second cavity  112 . 
     In some other embodiments of this application, the cross-sectional area of the connection channel  18  is 2 to 15 times the opening area of the microhole  115 . Specifically, it is set that the cross-sectional area of the connection channel  18  is 2 to 15 times the opening area of the microhole  115 , to precisely control the speed at which the airflow is exchanged between the first cavity  111  and the second cavity  112 . 
     Optionally, the cross-sectional area of the connection channel  18  is 4 to 9 times the opening area of the microhole  115 . Specifically, it is set that the cross-sectional area of the connection channel  18  is 4 to 9 times the opening area of the microhole  115 , to precisely control the speed at which the airflow is exchanged between the first cavity  111  and the second cavity  112 , and to avoid a case in which the microhole  115  is manufactured with an excessively small size to meet a multiple relationship between the opening area of the microhole  115  and the cross-sectional area of the connection channel  18 . In this way, the volume of airflow that enters and exits the second cavity  112  is controlled, and difficulty in disposing the microhole  115  is reduced. 
     In some other embodiments of this application, the aperture of the microhole  115  ranges from 0.5 mm to 2 mm. Specifically, the aperture of the microhole  115  is set to range from 0.5 mm to 2 mm, to effectively control the volume of airflow that enters and exits the second cavity  112 . 
     The foregoing description is merely example embodiments of this application, but is not intended to limit this application. Any modification, equivalent replacement, or improvement made without departing from the spirit and principle of this application should fall within the protection scope of this application.