Abstract:
A speaker includes a yoke, a diaphragm, an electrode plate, a magnet and a lower plate. The yoke includes a base, a wall and a terminal plate connected integrally to each other. The wall has a chamber and is mounted on the base. The rest components are mounted in the chamber. An amount of the components of the speaker is reduced because of the integral connection among the base and the wall. Consequently, the manufacturing costs and assembly process will be lowered and simplified.

Description:
BACKGROUND  
       [0001]     1. Field of Invention  
         [0002]     The present invention relates to a speaker, and more particularly to a small type speaker and the speaker has minimized components.  
         [0003]     2. Description of Related Art  
         [0004]     The operational function of a speaker is to transform electric signals into audio signals. Speakers are important output components for electric products, and can be integrated into many kinds of earphones or headsets, such as walkman, audio, radio, multimedia devices, recorders or portable digital dictionaries. Speakers also could be assembled into handsets for making phone calls.  
         [0005]     Speakers have different structures and sizes for different purposes. Among them are used in various earphones or walkmans, and the speakers are the small type speakers.  
         [0006]     Reference is made to  FIG. 1 , which illustrates an exploded perspective view of a conventional speaker. A speaker  100  comprises a front cover  110 , a diaphragm  120 , a voice coil  130 , an electrode plate  140 , a magnet  150 , a plastic yoke  160 , a terminal plate  170  and a lower plate  180 .  
         [0007]     The plastic yoke  160  provides a slot  161  for holding a terminal part  171  of the terminal plate  170  and a middle hole  162  in which the lower plate  180  is mounted. The lower plate  180  is like a tub and makes the plastic yoke  160  have a chamber  163  (Reference is made to  FIG. 2 ). And the terminal part  171  has a terminal  172  for connecting power cord. Hence, The magnet  150 , the electrode plate  140  and the voice coil  130  could be mounted and held in the chamber  163  in sequence. Lastly, putting the diaphragm  120  and covering the front cover  110  into the chamber  163  complete a small type speaker (Reference is made to  FIG. 3 ).  
         [0008]     The above-mentioned speaker  100  needs several components and manufacturing processes. The cost and manufacturing processes of fabricating the speakers  100  are generally high. Since the speakers  100  are demanded in mass production, the cost accumulated is considerable.  
       SUMMARY  
       [0009]     An objective of the present invention is to provide a speaker which could moderately reduce some components to lower the manufacturing costs of the speaker.  
         [0010]     Another objective of the present invention is to provide a speaker that is small in size for the demands of being mounted in those thin, light and short electric instruments. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]     The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the drawings,  
         [0012]      FIG. 1  is an exploded perspective view of a conventional speaker;  
         [0013]      FIG. 2  is a perspective view of a plastic yoke and terminal plate of the speaker in  FIG. 1 ;  
         [0014]      FIG. 3  is a cross-sectional view of the speaker in  FIG. 1 ;  
         [0015]      FIG. 4  is an exploded perspective view of a speaker of the preferred embodiment in accordance with the present invention;  
         [0016]      FIG. 5  is a perspective view of a terminal plate of the speaker in  FIG. 4 ;  
         [0017]      FIG. 6  is a cross-sectional view of the speaker in  FIG. 4 ; and  
         [0018]      FIG. 7  is a perspective view of the speaker in  FIG. 4 . 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0019]     Reference is now made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.  
         [0020]     While the specification concludes with claims defining the features of the invention that are regarded as original, it is believed that the invention is better understood from a consideration of the following description in conjunction with the figures, in which like reference numerals are carried forward.  
         [0021]     Reference is made to  FIG. 4 , which illustrates an exploded perspective view of a speaker of the preferred embodiment in accordance with the present invention (In order to express the accurate structure of the speaker and apt to describe it, the present invention&#39;s figures illustrates in opposite orientation to prior art). A speaker  200  comprises a yoke  210 , a diaphragm  220 , a voice coil  230 , an electrode plate  240 , a magnet  250  and a lower plate  260 .  
         [0022]     The yoke  210  comprises a terminal plate  211 , a base  216  and a wall  217 . The base  216  and the wall  217  are made of insulating material, such as plastic.  
         [0023]     The wall  217  is integrally mounted on the base  216  and can be a ring, a chamber is defined inside the wall  217 . The wall  217  has a first step  213  and a second step  214  formed inside the chamber and a gap  215  defined in the wall  217 .  
         [0024]     The terminal plate  211  is mounted on the base  216  for connecting a power cord. The base  216  has an acoustic hole  212 . The acoustic hole  212  is defined completely through the base  216  and communicates with the chamber of the wall  217 . The base  216  has four corners extended out of the edge of the wall  217  onto which the terminal plate  211  is mounted.  
         [0025]     Reference is made to  FIG. 4  and  FIG. 5 , which illustrate the terminal plate  211  of the preferred embodiment in accordance with the present invention. The terminal plate  211  includes a first connecting zone  2113 , a second connecting zone  2114  and at least one molding hole  2112 . The first connecting zone  2113  and the second connecting zone  2114  are generally “C” shaped and are arranged opposite to each other. Therefore, a gap  2111  and a through hole  2115  are defined between the first connecting zone  2113  and the second connecting zone  2114 . The terminal plate  211  has a parting line  2116  which is preformed adjacent to the first connecting zone  2113  and the second connecting zone  2114  of the terminal plate  211 . The first connecting zone  2113  and the second connecting zone  2114  can be separated from each other by breaking a part of the terminal plate  211  along the parting line  2116 .  
         [0026]     The terminal plate  211  can integrally be mounted with the base  216  and the wall  217  during the process of molding the base  216  and the wall  217 . The wall  217  passes through and is held in the through hole  2115 . The first connecting zone  2113  and the second connecting zone  2114  are mounted on the opposite pairs of corners of the base  216  respectively. Wires of the voice coil  230  could be connected to the zones  2113 ,  2114  of the terminal plate  211  via the gap  215  respectively. Hence, no additional terminals on the outer side of the wall  217  are needed, which could reduce the entire working height of the speaker. This speaker can be made small to meet the demands for speakers assembled into light, thin, short and small devices.  
         [0027]     Reference is made to  FIG. 4  and  FIG. 6  ( FIG. 6  is a cross-sectional view of a speaker of the preferred embodiment in accordance with the present invention).  
         [0028]     The diaphragm  220  is also called a vibrating film and could be made by paper, plastic or metallic materials. The edge of the diaphragm  220  could be connected to the second step  214  of the yoke  210 . The voice coil  230  connects to the diaphragm  220 . When the voice coil  230  vibrates, it could make the diaphragm  220  vibrate simultaneously, the vibration of the air around the diaphragm  220  turns into sound vibrations  
         [0029]     The wires of the voice coil  230  pass through the gap  215  of the yoke  210  and connect to the terminal plate  211 . When the voice coil  230  is energized, the metal wire could generate an electromagnetic field, and the strength of the electromagnetic field and the field of the magnet  250  are about the same. The positive pole and the negative pole of the coil exchange continuously, which changes the magnetic field of the coil and makes the coil shift forward and backward to cause the diaphragm  220  to vibrate and make sound.  
         [0030]     The magnet  250  and the electrode plate  240  are mounted in the chamber of the yoke  210  inside the wall  217 . The magnet  250  is a permanent magnet, which forms a permanent magnetic field. When the current passes through the voice coil  230 , the permanent field and the field of the voice coil  230  will be attractive or repulsive to each other; when the direction of current changes, so does the direction of the magnetic field; namely each time the direction of current changes, the voice coil  230  will produce a vibration.  
         [0031]     The lower plate  260  includes a protruding pole  261  that could pass through the voice coil  230 , and the lower plate  260  includes an air hole  262 . The air hole  262  could be a single hole or a plurality of holes. The lower plate  260  could be mounted against the first step  213  of the yoke  210  by a fastening means such as glue or solder. This results in the diaphragm  220 , the voice coil  230 , the electrode plate  240 , the magnet  250  and the lower plate  260  being assembled into the yoke  210  to form the speaker  200 .  
         [0032]     If any component needs to be disassembled, opening the lower plate  260  first, then the diaphragm  220 , the voice coil  230 , the electrode plate  240  and the magnet  250  can be removed without having to break the soldered voice coil  230  wire.  
         [0033]     Reference is made to  FIG. 5  and  FIG. 7 .  FIG. 7  illustrates an perspective view of a speaker of the preferred embodiment in accordance with the present invention. After the terminal plate  211 , the base  216  and the wall  217  are assembled together, a part of the terminal plate  211  is cut along the parting line  2116 . Therefore, the first connecting zone  2113  and the second connecting zone  2114  are separated and insulated electrically from each other.  
         [0034]     Therefore, the assembling process of the speaker is an inverse operation comparing to that of the conventional speaker. The diaphragm  220  is mounted into the yoke  210 . The voice coil  230  is mounted into the yoke  210  and connected to the diaphragm  210 . The electrode plate  240 , the magnet  250  and the lower plate  260  are mounted to the speaker yoke  210  in sequence. The speaker in accordance with the present invention is easier to assemble than conventional speaker because of the inverse assembling process.  
         [0035]     According to the composition and the embodiments above, there are many advantages of the present invention over the prior art, such as:  
         [0036]     1. The yoke and the terminal plate are assembled simultaneously, which will reduce the components and lower the costs.  
         [0037]     2. The terminal plate is mounted on the corners of the base so that the size and volume of the entire yoke is efficiently reduced.  
         [0038]     3. The corresponding “C” shaped connecting zones of the metal terminal plate are covered by the yoke, which makes the yoke more solid, and the strength and durability of the speaker also increase obviously.  
         [0039]     4. Because the terminal plate and the yoke are assembled together, the strength and the reliability among those components will be increased.  
         [0040]     It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.