Patent Publication Number: US-8532326-B2

Title: Fastener structure and reversed sounding structure using the same

Description:
This application claims the benefit of Taiwan application Serial No. 100114518, filed Apr. 26, 2011, the subject matter of which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates in general to a fastener structure, and more particularly to a fastener structure and a reversed sounding structure using the same. 
     2. Description of the Related Art 
     Referring to  FIG. 1 , a cross-sectional view of a conventional sound tank structure is shown. In the conventional sound tank structure  100 , the speaker unit  120  normally contacts the circuit board  130  through an electrode  122  disposed at the bottom or by way of soldering the circuit board  130  through a wire. Due to the restriction in the height, if the bottom of the speaker unit  120  is directly disposed on the circuit board  130 , the venting side must face upwards and cannot face the vent (not illustrated). Consequently, the position of the vent of the sound tank housing  110  is not conformed to the design requirements. Moreover, if the bottom of the speaker unit  120  faces upwards, there will be no electrical conduction between the bottom of the electrode  122  and the circuit board  130 . 
     According to the prior method for resolving the problem of electrical conduction, a wire is soldered on the bottom electrode of the speaker unit, and then the speaker unit is electrically connected to the circuit board through a connector or by way of soldering. However, the prior method which requires high assembly cost and involves complicated procedures is not suitable for mass production. 
     SUMMARY OF THE INVENTION 
     The invention is directed to a reversed sounding structure and a fastener structure using the same for resolving the problem of electrical conduction to facilitate assembly and save cost. 
     According to a first aspect of the present invention, a fastener structure for retaining a speaker unit on a sound tank housing is provided. The fastener structure includes a spring piece and an elastic protrusion rib. The spring piece includes a board, a first bending portion and a second bending portion. The board located within a through hole of the sound tank housing. The first bending portion located at one end of the board is for retaining the speaker unit on a second side of the sound tank housing. The second bending portion located at the other end of the board is exposed over a first side of the sound tank housing and used as an elastic contact. The elastic protrusion rib is disposed within the through hole, and is protruded from one side of the board to lean against between the board and the through hole, so that the board is wedged within the through hole. 
     According to a second aspect of the present invention, a reversed sounding structure including a sound tank housing, a speaker unit and a fastener is provided. The sound tank housing has a front sound tank disposed on a first side of the sound tank housing. The speaker unit includes an electrode and a speaker, wherein the electrode is located on a bottom surface of the speaker, and a venting side of the speaker is located on the sound tank housing for emitting a vibration sound to the front sound tank. The fastener is for fixing the speaker unit on a second side of the sound tank housing, and one end of the fastener is elastically retained on the bottom surface of the speaker, and is electrically connected to the electrode. 
     The above and other aspects of the invention will become better understood with regard to the following detailed description of the preferred but non-limiting embodiment(s). The following description is made with reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a cross-sectional view of a generally known sound tank structure; 
         FIGS. 2A and 2B  respectively show an assembly diagram and a decomposition diagram of a reversed sounding structure according to an embodiment of the invention; 
         FIG. 3  shows a bottom view of a reversed sounding structure according to an embodiment of the invention; 
         FIG. 4  shows a cross-sectional view of a reversed sounding structure; 
         FIGS. 5A and 5B  respectively show a layout diagram and a side exploration diagram of a reversed sounding structure according to an embodiment of the invention; 
         FIGS. 6 and 7  respectively show a 3D schematic diagram of a fastener structure according to an embodiment of the invention; and 
         FIG. 8  shows a cross-sectional view of a fastener structure disposed within a through hole according to an embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In the reversed sounding structure and the fastener structure of the present embodiment, a speaker unit and a sound tank housing are reversed on a circuit board, so that the bottom electrode faces upwards, and the venting side of the speaker faces downwards. The reversed speaker unit can be fixed on one side of the sound tank housing through a set of fasteners, and one end of each fastener is elastically retained on the bottom surface of the speaker and electrically connected to the electrode on the bottom surface. The reversed sounding structure of the present embodiment has a miniaturized volume, so that the space utilization rate is increased, the position of the vent of the front sound tank is conformed to the appearance requirements and the appearance design with a lateral vent is thus achieved. 
       FIGS. 2A and 2B  respectively show an assembly diagram and a decomposition diagram of a reversed sounding structure according to an embodiment of the invention.  FIG. 3  shows a bottom view of a reversed sounding structure according to an embodiment of the invention. 
     As indicated in  FIGS. 2A and 2B , the reversed sounding structure  200  includes a sound tank housing  210 , a speaker unit  220  and a fastener  230 . The sound tank housing  210  has a front sound tank  212  located on a first side  210   a  of the sound tank housing  210 . The speaker unit  220  includes an electrode  222  and a speaker  224 . The electrode  222  is located on a bottom surface  224   a  of the speaker  224 , and a venting side  224   b  of the speaker  224  is disposed on the sound tank housing  210  for emitting a vibration sound to the front sound tank  212 . The fastener  230  is for fixing the speaker unit  220  on a second side  210   b  of the sound tank housing  210 , wherein one end of the fastener  230  is elastically retained on the bottom surface  224   a  of the speaker  224  and is electrically connected to the electrode  222 . 
     As indicated in  FIGS. 2A and 2B , the electrode  222  of the speaker unit  220  faces upwards, and the venting side  224   b  of the speaker  224  faces downwards, so that the vibration sound outputted by the speaker  224  is emitted via a lateral vent  212   a  of the front sound tank  212 . Thus, the position of the vent side  224   b  is conformed to the appearance requirements of the lateral vent  212   a.    
     In addition, the electrode  222  of the speaker unit  220  includes as anode spring piece  222   a  and a cathode spring piece  222   b . The anode spring piece  222   a  is located on one side of the speaker  224 . The cathode spring piece  222   b  is located on the other side of the speaker  224 . The anode spring piece  222   a  and the cathode spring piece  222   b  are electrically connected to the anode and the cathode of the speaker  224  respectively for inputting a working voltage. Thus, when the working voltage is inputted, the thin film inside the speaker  224  is vibrated for emitting a vibration sound. Also, there can be two fasteners  230 , namely, the first fastener  230   a  and the second fastener  230   b . The first fastener  230   a  is located on one side of the speaker  224  and is bent towards the bottom surface  224   a  of the speaker  224  to form a bending portion for retaining the anode spring piece  222   a . The second fastener  230   b  is located on the other side of the speaker  224  and is bent towards the bottom surface  224   a  of the speaker  224  to form a bending portion for retaining the cathode spring piece  222   b . Thus, the first fastener  230   a  and the second fastener  230   b  are elastically retained on the bottom surface  224   a  of speaker  224  and are electrically connected to the anode spring piece  222   a  and the cathode spring piece  222   b  respectively. 
     In an embodiment, the reversed sounding structure  200  further includes a first sealing material  240  made from a sponge or other porous materials. The first sealing material, such as a bar-shaped sponge, is attached in a manner surrounding the sound tank housing  210  and used as a noise wall. Besides, the reversed sounding structure further includes a second sealing material  250  made from a sponge or other porous materials. The second sealing material  250 I, such as a bar-shaped sponge, is attached in a manner surrounding the lateral vent  212   a  of the front sound tank  212  and used as the other noise wall. 
     As indicated in  FIG. 3 , the front sound tank  212  is such as a U-shaped cover with a lateral vent  212   a . The bottom of the U-shaped cover is fixed on the first side  210   a  of the sound tank housing  210 , so that the lateral vent  212   a  faces a venting direction (indicated by the arrow B of  FIG. 2B ) of the sound tank housing  210 . As indicated in  FIG. 2B , the sound tank housing  210  has an exit  211  near the bottom of the front sound tank  212  via which the vibration sound is emitted to. Thus, when the venting side  224   b  of the speaker  224  emits a vibration sound, the sound wave is transmitted forwards to the front sound tank  212  via the exit  211  in a direction as indicated by the arrow A of  FIG. 2B . After the sound wave is reflected by the front sound tank  212  and resonation is generated, the sound wave is transmitted outwards via the lateral vent  212   a  in a direction as indicated by the arrow B of  FIG. 2B . 
     As indicated in  FIG. 2B and 3 , the sound tank housing  210  has a through hole  213  which penetrates to the second side  210   b  from the first side  210   a . The fastener  230  is disposed within the through hole  213 , and the other end is exposed over the first side  210   a  of the sound tank housing  210  and used as an elastic contact  230   c.    
       FIG. 4  shows a cross-sectional view of a reversed sounding structure.  FIGS. 5A and 5B  respectively show a layout diagram and a side exploration diagram of a reversed sounding structure according to an embodiment of the invention. 
     As indicated in  FIG. 4 , the reversed sounding structure  200  further includes an outer casing  260  which has a divider  262  inside. The divider  262  is jointed to the surrounding of the sound tank housing  210 , so that a chamber  260   a  is formed between the outer casing  260  and the sound tank housing  210 . In an embodiment, the size of the chamber  260   a  is larger than that of the speaker unit  220  so that the speaker unit  220  can be received in the chamber  260   a . In  FIG. 4 , the chamber  260   a  is located at the rear of the speaker unit  220 , so that the chamber  260   a  can be used as a rear sound tank of the speaker unit  220 . When the venting side  224   b  of the speaker unit  220  emits a vibration sound, a part of the sound wave generates resonation within the rear sound tank and the characteristics of the sound wave are changed accordingly. Based on the resonation between the front and the rear sound tanks, the speaker unit  220  adjusts the tone quality accordingly. 
     In  FIG. 4 , the sound tank housing  210  covers the top surface of the divider  262 , and the first sealing material  240  is sealed between the divider  262  and the sound tank housing  210  and used as a noise wall. In addition, the front sound tank  212  is engaged with an acoustical board  264  of the outer casing  260 , and the second sealing material  250  is sealed between the front sound tank  212  and the acoustical board  264  and used as the other noise wall. Thus, the sound wave vibrating within the front and the rear sound tanks is isolated from the exterior so that the resonation is enhanced and the vibration sound is transmitted to the exterior of the outer casing  260  via the lateral vent  212   a.    
     The reversed sounding structure  200  further includes a circuit board  270  disposed on the first side  210   a  of the sound tank housing  210 , so that the reversed speaker unit  220  and the sound tank housing  210  are enclosed between the outer casing  260  and the circuit board  270 , and the reversed speaker unit  220  can be electrically connected to the circuit board  270  via the fastener  230 . The fastener  230  is for transmitting the signal inputted by the circuit board  270  to the speaker unit  220  for driving the speaker  224  to emit a vibration sound. 
       FIGS. 6 and 7  respectively show a 3D schematic diagram of a fastener structure according to an embodiment of the invention.  FIG. 8  shows a cross-sectional view of a fastener structure disposed within a through hole according to an embodiment of the invention. To elaborate the fastener  230  wedged within the through hole  213  in greater details, the details structures of the fastener  230  are illustrated in  FIGS. 6 and 7  but the through hole  213  of the sound tank housing  210  is not illustrated. As indicated in  FIGS. 6 ,  7  and  8 , the fastener  230  includes a spring piece  231  and an elastic protrusion rib  235 . The spring piece  231  includes a board  232 , a first bending portion  233  and a second bending portion  234 . The board  232  is located within a through hole  213  of the sound tank housing  210  as indicated in  FIG. 8 . The first bending portion  233  is located at one end of the board  232  for retaining the speaker unit  220  on one side (that is, the second side  210   b ) of the sound tank housing  210  as indicated in  FIG. 2A . The second bending portion  234  is located at the other end of the board  232  and is exposed over the opposite side (that is, the first side  210   a ) of the sound tank housing  210  and used as an elastic contact  230   c  as indicated in  FIG. 3 . The elastic protrusion rib  235  is disposed within the through hole  213 , wherein the elastic protrusion rib  235  leans against between the board  232  and the through hole  213 , so that the board  232  is wedged within the through hole  213 . 
     In an embodiment, the first bending portion  233  and the second bending portion  234 , such as L-shaped bending portions, integrally form a U-shaped structure with the board  232 , so that the spring piece  231  has the functions of elastic retaining and electrical conduction. In addition, a colloid  239 , such as a thermosetting colloid, can be interposed into the through hole  213  of the sound tank housing  210 , so that the board  232  of the spring piece  231  can be fixed within the through hole  213  through the colloid  239  dispensed within the through hole  213 . 
     The elastic protrusion rib  235  can be a deformable metal piece protruded from one side of the board  232 . As indicated in  FIG. 7 , the elastic protrusion rib  235  can be integrally formed in a recess  237  of the board  232  as a tongue  236  by way of stamping. The terminal end of the tongue  236  is not truncated but is fixed on the board  232 , so that the front end  236   a  of the tongue  236  can be protruded outwards. In the present embodiment, the tongue  236  is elastically bent so that the front end  236   a  is obliquely protruded from the recess  237  for at least a thickness W 1 . When the tongue  236  is disposed within the through hole  213 , the front end  236   a  of the tongue  236  is squeezed and dented into the recess  237 , and the generated deformation is about the same with the displacement of the front end  236   a  of the tongue  236 . In the present embodiment, the board  232  is wedged within the through hole  213  through the deformation of the elastic protrusion rib  235 . Thus, the first bending portion  233  located at one end of the board  232  as indicated in  FIG. 2A  retains the speaker unit  220  on one side (that is, the first side  210   a ) of the sound tank housing  210 , and the second bending portion  234  located at the other end of the board  232  is exposed over an opposite side (that is, the second side  210   b ) of the sound tank housing  210  and used as an elastic contact  230   c . The elastic contact  230   c  is electrically connected to the circuit board  270  (referring to  FIG. 4 ), so that the spring piece  231  is electrically connected between the circuit board  270  and the speaker unit  220  for transmitting the signal inputted by the circuit board  270  to the speaker unit  220  for driving the speaker  224  to emit a vibration sound. 
     As indicated in  FIGS. 7 and 8 , the board  232  has at least a dented portion  238  disposed within the through hole  213 , wherein the dented portion  238  is protruded towards the other side of the board  232  for a thickness W 2 , so that the dented portion  238  leans against between the board  232  and the through hole  213 . In an embodiment, there are two dented portions  238  integrally formed a bottom of the board  232  by way of stamping. The total thickness of the bottom of the processed board  232  and the dented portion  238  being W 2 +W 3  is larger than the original thickness of the board  232  being W 3 . The thickness of the lower part of the board  232  is increased but the thickness of the upper part of the board  232  remains unchanged, so that the upper part of the board  232  can pass through the through hole  213  and the lower part of the board  232  is wedged within the through hole  213 . 
     In an embodiment, the elastic protrusion rib  235  leans against the first hole wall  213   a  of the through hole  213 , and the dented portion  238  leans against the second hole wall  213   b  of the through hole  213 . The distance between the first hole wall  213   a  and the second hole wall  213   b  is the aperture W 4  of the through hole  213 . As indicated in  FIG. 8 , when a tolerance gap (loose matching) exists between the through hole  213  and the lower part of the board  232 , that is, when the aperture of the through hole  213  is larger than the total thickness of the lower part of the board  232 , W 4 &gt;W 2 +W 3 , the elastic protrusion rib  235  will be protruded from one side of the board  232  for at least a thickness to compensate the tolerance gap. In other embodiments, when there is no tolerance gap between the through hole  213  and the lower part of the board  232  (tight matching), that is, when the aperture W 4  of the through hole  213  is about the same with the total thickness of the lower part of the board  232 , W 4 ≈W 2 +W 3 , the elastic protrusion rib  235  will not be protruded from one side of the board  232  but will be dented into the recess  237  instead. Thus, regardless the matching between the through hole  213  and the board  232  is loose matching or tight matching, the tightness of matching can be adjusted through the deformation of the elastic protrusion rib  235  for wedging the board  232  within the through hole  213 . 
     According to the reversed sounding structure and the fastener structure disclosed in the above embodiments, the speaker unit and the sound tank housing are reversed on the circuit board, so that the bottom electrode faces upwards and the venting side of the speaker faces downwards. Thus, the position of the vent of the front sound tank is conformed to the appearance requirements and the appearance design with a lateral vent is thus achieved. In addition, the reversed speaker unit can be fixed on one side of the sound tank housing through a set of fastener, and one end of each fastener is elastically retained on the bottom surface of the speaker and electrically connected to the bottom electrode. The fastener has elastic retaining function and can also be electrically connected between the speaker unit and the circuit board. In comparison to the prior solution for resolving the electrical conduction problem by way of soldering, the fastener of the present embodiment being a metal piece integrally formed in one piece can be wedged within the through hole as an element for electrical conduction without using additional soldering wire or connector. Therefore, the fastener of the present embodiment is easy to assemble, incurs low assembly cost and is suitable for mass production. 
     While the invention has been described by way of example and in terms of the preferred embodiment(s), it is to be understood that the invention is not limited thereto. On the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures.