Abstract:
The present invention relates to a slim protector with a small thickness and a slim microspeaker having the same. The present invention provides a slim protector, which can reduce the thickness of a slim microspeaker by removing part of an injection product portion and exposing a steel portion to form a ledge for connecting a module case and the slim protector and allow the steel portion and the module case to engage other, and a slim microspeaker module having the same.

Description:
PRIORITY CLAIM 
       [0001]    The present application claims priority to Korean Patent Application No. 10-2013-0016379 filed on 15 Feb. 2013, the content of said application incorporated herein by reference in its entirety. 
       TECHNICAL FIELD 
       [0002]    The present invention relates to a slim protector which is made thin and a slim microspeaker having the same. 
       BACKGROUND 
       [0003]    Nowadays, multimedia devices such as TVs, smart phones, etc are being made thinner and slimmer overall. In line with this trend, microspeakers mounted on multimedia are required to have a slim profile. 
         [0004]      FIGS. 1 and 2  are views showing a conventional microspeaker. A yoke  21 , an inner ring magnet  22 , an outer ring magnet  23 , an inner ring top plate  24 , and an outer ring top plate  25  are installed within a frame  10 , and a voice coil  30  is placed in an air gap between the inner ring magnet  22  and the outer ring magnet  23 , and vibrates vertically when power is applied to the voice coil  30 . The voice coil  30  is mounted to the bottom side of a damper  50 , and a side diaphragm  41  and a center diaphragm  42  are installed on the top and bottom sides of the damper  50 , vibrate in synchrony with the vibration of the voice coil  30 , and produce a sound. A protector  60  is connected to the top of the side diaphragm  41  and center diaphragm  42  to protect the parts located inside the speaker. The protector  60  includes a ring-shaped steel portion  61  with an opening  63  in the middle to emit sound, and a ring-shaped injection product portion  62 , into which the steel portion  61  is insert injection-molded, and which is laminated on top of the frame  10 , the outer periphery of the side diaphragm  41 , and the outer periphery of the damper  50 . 
         [0005]      FIG. 3  is a view showing a connecting portion of a microspeaker and a module case according to the conventional art. 
         [0006]    The protector  60  of the conventional microspeaker is connected to a module case  1100  and  1200  surrounding the exterior of the microspeaker. The module case  1100  and  1200  includes a lower module case  1100  and an upper module case  1200 , and the upper module case  1200  has a ledge  1210  that projects inward than the outer circumference of the microspeaker and presses down the microspeaker from above. The protector  60  also has a ledge that engages the ledge  1210  of the upper module case  1200  so as to maintain its position relative to the module case  1100  and  1200  without deviating from its original position. The ledge of the protector  60  is a stepped portion  62   a  which is formed with a relatively small thickness on the outer edge of the injection product portion  62 . As the ledge  1210  of the module case  1200  having a predetermined thickness is connected to the stepped portion  62   a  of the injection product portion  62 , the thickness of the stepped portion  62   a  or the thickness of the ledge  1210  of the module case  1200  needs to be reduced in order to reduce the thickness of the microspeaker module. However, if the injection thickness of the stepped portion  62   a  becomes too small, its strength may get lower. Therefore, the stepped portion  62  needs to have an injection thickness of 0.15 mm or greater, and the introduction of a high-performance injector having high capacity is required. 
       SUMMARY 
       [0007]    An object of the present invention is to provide a slim protector, which can reduce the thickness of a slim microspeaker by removing part of an injection product portion and exposing a steel portion to form a ledge for connecting a module case and the slim protector and allow the steel portion and the module case to engage other, and a slim microspeaker module having the same. 
         [0008]    Another object of the present invention is to provide a slim protector, which can prevent the creation of a gap between a portion for injection to the inside of a steel portion and a portion for injection to the outside of the steel portion by forming holes in the steel portion to increase the coupling force between the steel portion and the injection portion, and a slim microspeaker module having the same. 
         [0009]    Yet another object of the present invention is to provide a slim protector, which improves bending strength by forming downward protruding ribs on the top side of a steel portion, and a slim microspeaker module having the same. 
         [0010]    The present invention provides a slim protector equipped in a slim microspeaker module comprising a microspeaker and a module case surrounding the exterior of the microspeaker, the protector including: a ring-shaped injection product portion whose outer periphery is shaped to engage a frame and which is hollow in the center; and a steel portion which is insert injection-molded and connected to the injection product portion and which has a top side exposed to the inside of the injection portion, an outer peripheral portion being shorter in height than the top side, and a sloped side provided between the outer peripheral portion and the top side, wherein a ledge for engaging the module case is formed with the outer peripheral portion of the steel portion exposed by removing part of the injection product portion. 
         [0011]    According to another aspect of the present invention, the outer peripheral portion and the sloped side are formed only in the portion exposed by removing the injection portion. 
         [0012]    According to another aspect of the present invention, the sloped side includes via holes through which an injection product portion for injection to the inside of the steel portion and an injection product portion for injection to the outside of the steel portion are connected to prevent the creation of a gap between the steel portion and the injection portions inside and outside the steel portion. 
         [0013]    According to another aspect of the present invention, downward protruding ribs are formed on the top side of the steel portion to improve bending strength. 
         [0014]    Furthermore, the present invention provides a slim microspeaker module including: a microspeaker having the slim protector described above, a frame, a yoke, inner and outer ring magnets, inner and outer ring top plates, a voice coil, a diaphragm, and a terminal; and a module case surrounding the exterior of the microspeaker. 
         [0015]    A slim protector and a slim microspeaker module having the same according to the present invention can reduce the overall thickness of a microspeaker module only by changing the shape of a ledge of the protector. 
         [0016]    Those skilled in the art will recognize additional features and advantages upon reading the following detailed description, and upon viewing the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]      FIGS. 1 and 2  are views showing a conventional microspeaker. 
           [0018]      FIG. 3  is a view showing a connecting portion of a microspeaker and a module case according to the conventional art. 
           [0019]      FIGS. 4 and 5  are views showing a slim protector according to a first embodiment of the present invention. 
           [0020]      FIGS. 6 and 7  are views showing a slim protector according to a second embodiment of the present invention. 
           [0021]      FIGS. 8 and 9  are views showing a slim protector according to a third embodiment of the present invention. 
           [0022]      FIG. 10  is a view showing a slim microspeaker module according to an embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0023]    Hereinafter, the present invention will be described in more detail with reference to the drawings. 
         [0024]      FIGS. 4 and 5  are views showing a slim protector  600  according to a first embodiment of the present invention. 
         [0025]    The slim protector  600  according to the first embodiment of the present invention includes a steel portion  610  and an injection product portion  620 . The steel portion  610  is made of a steel material having a predetermined strength to protect the parts inside a microspeaker, and has a top side  612  which is at a predetermined distance from parts such as a diaphragm. The steel portion  610  is insert injection-molded into the injection product portion  620 , and the injection product portion  620  has the shape of a ring which is hollow in the center so as to expose the top side  612  of the steel portion  610 . 
         [0026]    The steel portion  610  includes the top side  612  exposed to the inside of the injection product portion  620 , an outer peripheral portion  614  being shorter in height than the top side  612 , and a sloped side  616  provided between the outer peripheral portion  614  and the top side  612 . 
         [0027]    To form a ledge that engages a ledge of the module case, in the slim protector  600  according to the first embodiment of the present invention, part of the outer side of the injection product portion  620  is removed, thereby exposing the outer peripheral portion  614  of the steel portion  610 . As the exposed outer peripheral portion  614  and the ledge of the module case engage each other, the relative positions of the microspeaker and the module case can be fixed. 
         [0028]    Referring to  FIG. 3 , in the conventional art, part of the injection product portion  62  is removed to cause the stepped portion  62   a  and the ledge  1210  of the module case  1200  to engage each other. This requires the stepped portion  62   a  to have a thickness of at least 0.15 mm to achieve a predetermined strength. On the other hand, the outer peripheral portion  614  of the slim protector  600  according to the first embodiment of the present invention can be made much thinner than the stepped portion  62   a  according to the conventional art because the outer peripheral portion  614  of the steel portion  610  and the ledge of the module case engage each other and steel has higher strength than an injection-molded material. Accordingly, an assembled slim microspeaker module can be made much slimmer. 
         [0029]      FIGS. 6 and 7  are views showing a slim protector according to a second embodiment of the present invention. Like in the first embodiment, the slim protector according to the second embodiment of the present invention includes a steel portion  610 ′ and an injection product portion  620 ′. However, the shapes of the steel portion  610 ′ and the injection product portion  620 ′ are somewhat different from those of the first embodiment. The slim protector according to the second embodiment of the present invention includes a top side  612 ′ exposed to the inside of the injection product portion  620 ′, an outer peripheral portion  614 ′ being shorter in height than the top side  612 ′, and a sloped side  616 ′ provided between the outer peripheral portion  614 ′ and the top side  612 ′. To form a ledge that engages a ledge of the module case, part of the outer side of the injection product portion  620 ′ is removed, thereby exposing the outer peripheral portion  614 ′ of the steel portion  610 ′. The outer peripheral portion  614 ′ is formed not over the entire area, but only in the portion from which the injection product portion  620 ′ is removed. 
         [0030]    Further, as shown in  FIG. 7 , the injection product portion  620 ′ includes a lower injection product portion  622 ′ for injection to the bottom of the sloped side  616 ′ and an upper injection product portion  624 ′ for injection to the top of the sloped side  616 ′, both the lower injection product portion  622 ′ and the upper injection product portion  624 ′ being attached onto the steel portion  610 ′, which is a foreign material. Since the foreign material is adhered by insert injection-molding, the lower injection product portion  622 ′ and the upper injection product portion  624 ′ might fall off from the steel portion  610 ′, creating a gap between the lower and upper injection portions  622 ′ and  624 ′ and the steel portion  610 ′. To avoid this, via holes  618 ′ are formed on the sloped side  616 ′ of the steel portion  610 ′ in the protector according to the second embodiment. As an injection-molded material  626 ′ is filled in the via holes  618 ′ during injection-molding of the injection product portion  614 ′, the lower injection product portion  622 ′ and the upper injection product portion  624 ′ are connected by the injection-molded material  626 ′. This prevents the foreign material from falling off from the steep portion  610 ′ and creating a gap between the steep portion  610 ′ and the lower and upper injection portions  622 ′ and  624 ′. 
         [0031]      FIGS. 8 and 9  are views showing a slim protector according to a third embodiment of the present invention. Like in the first and second embodiments, the slim protector according to the third embodiment of the present invention includes a steel portion  610 ″ and an injection product portion  620 ″. However, the shape of the steel portion  610 ″ is somewhat different from those of the first and second embodiments. The slim protector according to the third embodiment of the present invention includes a top side  612 ″ exposed to the inside of the injection product portion  620 ″, an outer peripheral portion  614 ″ being shorter in height than the top side  612 ″, and a sloped side  616 ″ provided between the outer peripheral portion  614 ″ and the top side  612 ″. To form a ledge that engages a ledge of the module case, part of the outer side of the injection product portion  620 ″ is removed, thereby exposing the outer peripheral portion  614 ″ of the steel portion  610 ″. 
         [0032]    The slim protector according to the third embodiment of the present invention includes a plurality of downward protruding ribs  611 ″ which are formed on the top side  612 ″ to increase the strength of the top side  612 ″ of the steel portion  610 ″. As the overall height of the slim microspeaker module decreases by making the steel portion  610 ″ thinner, the steel portion  610 ″ becomes weaker in bending strength. To compensate for this, a plurality of ribs  611 ″ are formed. The downward protruding ribs  611 ″ have an advantage over upward protruding ribs in reducing the overall height of the slim microspeaker module. 
         [0033]      FIG. 10  is a view showing a slim microspeaker module according to an embodiment of the present invention. 
         [0034]    The microspeaker is configured as follows. A magnetic circuit comprising of a yoke  210 , an inner ring magnet  220 , an outer ring magnet  230 , an inner ring top plate  240 , and an outer ring top plate  250  is installed within a frame  100 . 
         [0035]    A voice coil  300  is placed in an air gap between the inner ring magnet  220  and the outer ring magnet  230 , and vibrates vertically when power is applied to the voice coil  300 . The voice coil  300  is mounted to the bottom side of a damper  500 , and a side diaphragm  410  and a center diaphragm  420  are installed on the top and bottom sides of the damper  500 , vibrate in synchrony with the vibration of the voice coil  300 , and produce a sound. A protector  600 ′ is connected to the top of the side diaphragm  410  and center diaphragm  420  to protect the parts located inside the speaker. Terminals  700  for receiving power from a device where the slim microspeaker module is mounted are installed on the frame  100 . 
         [0036]    The slim microspeaker module includes a lower module case  1100  to be connected to the bottom of the microspeaker and an upper module case  1200  to be connected to the top of the microspeaker. The upper module case  1200  includes a plurality of ledges  1210  that protrude upward of the microspeaker in order to prevent the microspeaker from falling out. Ledges for engaging the ledges  1210  are provided in the protector  600 ′. The ledges provided in the protector  600 ′ are formed by removing part of the outer side of the injection product portion  620 ′ and exposing the outer peripheral portion  614 ′ of the steel portion  610 ′. 
         [0037]    While a slim microspeaker module according to an embodiment of the present invention employs the protector according to the second embodiment of the present invention, it also may employ the protector according to the first embodiment of the present invention or the protector according to the third embodiment of the present invention. Besides, a protector having two or more of the features of the protectors according to the first, second, and third embodiments may be employed. 
         [0038]    Spatially relative terms such as “under”, “below”, “lower”, “over”, “upper” and the like, are used for ease of description to explain the positioning of one element relative to a second element. These terms are intended to encompass different orientations of the device in addition to different orientations than those depicted in the figures. Further, terms such as “first”, “second”, and the like, are also used to describe various elements, regions, sections, etc. and are also not intended to be limiting. Like terms refer to like elements throughout the description. 
         [0039]    As used herein, the terms “having”, “containing”, “including”, “comprising” and the like are open-ended terms that indicate the presence of stated elements or features, but do not preclude additional elements or features. The articles “a”, “an” and “the” are intended to include the plural as well as the singular, unless the context clearly indicates otherwise. 
         [0040]    With the above range of variations and applications in mind, it should be understood that the present invention is not limited by the foregoing description, nor is it limited by the accompanying drawings. Instead, the present invention is limited only by the following claims and their legal equivalents.