Abstract:
A nebulization structure includes a driving element, a structure plate and a nebulization plate. The structure plate is installed on a side of the driving element, and the structure plate is substantially in a circular disc shape and has a plurality of through holes, and at least one rib is formed between adjacent through holes to define a water guide passage. The nebulization plate is clamped between the driving element and the structure plate and made of a polymer material to overcome the problems of having easy metal fatigue and embrittlement of the nebulization plate made of metal, and being corroded by corrosive liquids.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This non-provisional application claims priority under 35 U.S.C. §119(a) on Patent Application No(s). 100221054 filed in Taiwan, R.O.C. on Nov. 8, 2011, the entire contents of which are hereby incorporated by reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a nebulization structure, in particular to the nebulization structure that uses a nebulization plate and a piezoelectric annular plate in a nebulization process. 
         [0004]    2. Description of the Related Art 
         [0005]    As science and technology advance and consumers have increasing higher requirements on a light, thin, short and compact design of various different products, different technical areas including medicine, bio-tech, computer technology, printing or energy industry tend to develop products with a fine and miniaturized design. 
         [0006]    With reference to  FIGS. 1 ,  2  and  3  for an exploded view, a perspective view and a cross-sectional view of a conventional nebulization structure respectively, the nebulization structure  1  is installed on a side of a cavity  14  and comprises a piezoelectric annular plate  11 , a nebulization plate  12  and a structure annular plate  13 . Wherein, both sides of the nebulization plate  12  are packaged and fixed between the piezoelectric annular plate  11  and the structure annular plate  13 . The structure annular plate  13  is provided for fixing the nebulization plate  12  and oscillated by the piezoelectric annular plate  11  to vibrate together with the piezoelectric annular plate  11 . 
         [0007]    When an electric field is applied to the piezoelectric annular plate  11  from the lateral side of the piezoelectric annular plate  11 , the piezoelectric annular plate  11  produces a transverse contraction and induces the deformation of the nebulization plate  12  to link the nebulization plate  12  and deform accordingly. Since the piezoelectric contraction produced by the piezoelectric annular plate  11  and the deformation of the nebulization plate  12  vary, the nebulization plate  12  of nebulization structure  1  is induced a curved movement to produce up and down oscillations of the nebulization plate  12 . 
         [0008]    When the operating frequency of the piezoelectric annular plate  11  is exactly equal to the vibration frequency of the overall structure, spray holes  121  formed on the nebulization plate  12  produce a very high speed of a spray, so that the inertia force of droplets formed on the spray holes  121  of the nebulization plate  12  is greater than the surface tension of the spray holes to spray micro droplets from the spray holes in order to achieve a fluid nebulization effect. 
         [0009]    Since metal has a better effect of transmitting the vibration energy, the conventional nebulization plate  12  is generally made of a metal material. Due to the limitation of the metal material, the metal nebulization plate  12  may become fatigued, embrittled, or gradually weaken in the oscillation effect easily to result in cracking the nebulization plate  12 , after the nebulization plate  12  has been operated at a high frequency oscillation for a long time. 
         [0010]    If the nebulization plate  12  is made of a polymer material instead, the drawbacks of the metal nebulization plate  12  can be overcome, but the polymer material has a loosened structural arrangement of molecules and an insufficient rigidity, the efficiency for the nebulization plate to receive the energy transmitted from the piezoelectric driving element becomes too low, so that the nebulization plate fails to transmit the vibration energy and results in a poor nebulization effect. 
         [0011]    In addition, the conventional structure annular plate  13  is an annular structure, so that when it is combined with the piezoelectric annular plate  11  and the nebulization plate  12  to form a nebulization structure, most of the vibration energy produced by the piezoelectric annular plate  11  can only be transmitted to the nebulization plate  12  which is relative to the inner side of the structure annular plate  13 , and thus causing the vibration energy failing to be transmitted to the center position of the nebulization plate  12  effectively. As a result, the center position of the nebulization plate  12  cannot be oscillated effectively, and the nebulization effect becomes low. 
       SUMMARY OF THE INVENTION 
       [0012]    Therefore, it is a primary objective of the present invention to provide a nebulization structure, particularly the nebulization structure that is applicable to corrosive liquids and has a nebulization plate capable of producing vibration energy up to a level that can achieve the expected nebulization effect. 
         [0013]    To achieve the aforementioned objective, the present invention provides a nebulization structure comprising a driving element, a structure plate and a nebulization plate. The structure plate is installed on a side of the driving element, and the structure plate is in a circular disc shape and has a plurality of through holes, and at least one rib formed between two adjacent through holes. The nebulization plate is clamped between the driving element and the structure plate. 
         [0014]    Wherein, the through holes are arranged radially into a circular shape with respect to the center position of the structure plate. 
         [0015]    Wherein, the driving element is a piezoelectric annular plate. 
         [0016]    Wherein, the structure plate further includes a plurality of glue overflow passages, each formed at the external periphery of each respective through hole and at a position corresponding to the internal periphery of the piezoelectric annular plate. 
         [0017]    Wherein, the nebulization plate and the structure plate are coupled and combined by an adhesive. 
         [0018]    Wherein, the nebulization plate is made of a polymer material or a metal material. 
         [0019]    Wherein, if the nebulization plate is made of a polymer material, the polymer material is polyimide, polyethylene (PE), polypropylene (PP) or polyether ether ketone (PEEK). 
         [0020]    Wherein, the structure plate is made of a metal material or a polymer material. 
         [0021]    Wherein, if the structure plate is made of a polymer material, the polymer material is polyimide, polyethylene (PE), polypropylene (PP) or polyether ether ketone (PEEK). 
         [0022]    Wherein, if there are three or four through holes, each through hole is arranged radially into a circular shape with respect to the center position of the structure plate. 
         [0023]    Wherein, if there are four through holes, one of the four through holes is formed at the center position of the structure plate and the other three through holes are arranged radially into a circular shape with respect to the center position of the structure plate. 
         [0024]    Wherein, if there are five through holes, one of the five through holes is formed at the center position of the structure plate and the other four through holes are arranged radially into a circular shape with respect to the center position of the structure plate. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0025]      FIG. 1  is an exploded view of a conventional nebulization structure; 
           [0026]      FIG. 2  is a perspective view of a conventional nebulization structure; 
           [0027]      FIG. 3  is a cross-sectional view of a conventional nebulization structure; 
           [0028]      FIG. 4  is a perspective view of a nebulization structure in accordance with a first preferred embodiment of the present invention; 
           [0029]      FIG. 5  is a perspective view of a nebulization structure in accordance with the first preferred embodiment of the present invention; 
           [0030]      FIG. 6  is a cross-sectional view of a nebulization structure in accordance with the first preferred embodiment of the present invention; 
           [0031]      FIG. 7  is a schematic view of an operation of a nebulization structure in accordance with the first preferred embodiment of the present invention; 
           [0032]      FIG. 8  is a schematic microscopic view of an operation of a nebulization structure in accordance with the first preferred embodiment of the present invention; 
           [0033]      FIG. 9  is a schematic view of another implementation mode of a structure plate of a nebulization structure in accordance with the first preferred embodiment of the present invention; 
           [0034]      FIG. 10  is a schematic view of another implementation mode of a structure plate of a nebulization structure in accordance with the first preferred embodiment of the present invention; 
           [0035]      FIG. 11  is a schematic view of another implementation mode of a structure plate of a nebulization structure in accordance with the first preferred embodiment of the present invention; 
           [0036]      FIG. 12  is a schematic view of another implementation mode of a structure plate of a nebulization structure in accordance with the first preferred embodiment of the present invention; 
           [0037]      FIG. 13  is a schematic view of another implementation mode of a structure plate of a nebulization structure in accordance with the first preferred embodiment of the present invention; 
           [0038]      FIG. 14  is a schematic view of another implementation mode of a structure plate of a nebulization structure in accordance with the first preferred embodiment of the present invention; 
           [0039]      FIG. 15  is an exploded view of a nebulization structure in accordance with a second preferred embodiment of the present invention; 
           [0040]      FIG. 16  is a schematic view of another implementation mode of a structure plate of a nebulization structure in accordance with the second preferred embodiment of the present invention; 
           [0041]      FIG. 17  is a schematic view of another implementation mode of a structure plate of a nebulization structure in accordance with the second preferred embodiment of the present invention; and 
           [0042]      FIG. 18  is a schematic view of another implementation mode of a structure plate of a nebulization structure in accordance with the second preferred embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0043]    The technical content of the present invention will become apparent with the detailed description of preferred embodiments and the illustration of related drawings as follows. 
         [0044]    With reference to  FIGS. 4 ,  5  and  6  for perspective views and a cross-sectional view of a nebulization structure in accordance with the first preferred embodiment of the present invention respectively, the nebulization structure  2  is installed on a side of a cavity  24  and comprises a driving element  21 , a structure plate  22  and a nebulization plate  23 . 
         [0045]    In this preferred embodiment, the driving element  21  is a piezoelectric annular plate made of a piezoelectric ceramic material. 
         [0046]    The structure plate  22  is installed on a side of the driving element  21 . In this preferred embodiment, the structure plate  22  is in a circular disc shape and includes a plurality of through holes  221 , and at least one rib  222  formed between two adjacent through holes. In this preferred embodiment, there are five through holes  221 , wherein one of the five through holes  221  is formed at the center position of the structure plate  22 , and the other four through holes  221  are arranged radially in a circular shape with respect to the center of the structure plate  22 . In this preferred embodiment, the structure plate  22  is preferably made of metal to provide a better effect of transmitting vibration energy. Of course, the material is not limited to metal only, but it also can be a polymer such as polyimide, polyethylene (PE), polypropylene (PP) or polyether ether ketone (PEEK). 
         [0047]    The nebulization plate  23  is clamped between the driving element  21  and the structure plate  22  and has a plurality of firing holes  231 . In this preferred embodiment, the nebulization plate  23  is made of a polymer such as polyimide, polyethylene (PE), polypropylene (PP) or polyether ether ketone (PEEK) to prevent the nebulization plate  23  from being embrittled or having metal fatigue by high frequency oscillations for a long time which results in a gradually decreasing oscillation effect or a crack of the nebulization plate  23 . However, the material used for making the nebulization plate  23  is not limited to the aforementioned polymers only, but it can also be made of metal depending on actual requirements. Wherein, at least one rib  222  formed on the structure plate  22  can support the nebulization plate  23  and combine with the nebulization plate  23  more securely, so that the vibration energy produced by the driving element  21  can be transmitted to the structure plate  22  directly, and then the structure plate  22  produces vibrations directly to drive the nebulization plate  23  to nebulize a liquid. Therefore, the oscillation frequency for the operation of the combined nebulization plate  23  and structure plate  22  is close to the oscillation frequency of the driving element  21 , so that a better nebulization effect can be achieved. 
         [0048]    With reference to  FIGS. 7 and 8  for a schematic view and a schematic microscopic view of an operation of a nebulization structure of the present invention respectively, the driving element  21  is driven by an electric field to expand and contract transversally during the operation of the nebulization structure  2  in order to drive the nebulization plate  23  to oscillate. A liquid to be nebulized and contained in the cavity  24  is transmitted through a plurality of guide passages formed by the at least one rib  222  and through the through hole  221  to a plurality of firing holes  231  of the nebulization plate  23 . In addition, the rib  222  can transmit the oscillation energy to the nearby firing holes  231  through an energy transmission passage formed by the driving element  21 . When the liquid to be nebulized and the vibration energy are transmitted to the firing holes  231 , the high speed produced at the neighborhood of the firing hole  231  makes the inertia force of the nebulized droplets greater than the surface tension of the liquid to be nebulized at the firing holes  231 , so that the micro droplets can be sprayed out from the firing holes  231  to achieve a fluid nebulization effect. In addition, due to the thickness of the structure plate, a mini cavity is formed by the through hole on the structure plate so as to reduce of the back pressure of the liquid to be nebulized to improve the nebulization effect. 
         [0049]    In other implementation modes, the structure plate  22  has three, four or more through holes, and the through holes  221  are symmetrically and radially arranged with respect to the center of the structure plate  22 , and one of the through holes  221  is formed at the center position of the structure plate  22 , but the invention is not limited to such arrangement only, but it can also be arranged as shown in  FIGS. 9 to 14 . 
         [0050]    With reference to  FIG. 15  for an exploded view of a nebulization structure in accordance with the second preferred embodiment of the present invention, the nebulization structure  3  is installed on a side of a cavity  34  and comprises a driving element  31 , a structure plate  32  and a nebulization plate  33 . The structure plate  32  has a plurality of through holes  321  formed thereon and at least one rib  322  formed between two adjacent through holes  321 . 
         [0051]    In this preferred embodiment, the structure and functions of the driving element  31 , the rib  322  and the nebulization plate  33  are the same as those of the first preferred embodiment, and thus will not be described. The difference of this preferred embodiment and the first preferred embodiment resides on that the structure plate  32  further includes a plurality of glue overflow passages  35  formed thereon and disposed with an interval apart at the external periphery of the through holes  321  and at positions corresponding to the internal periphery of the piezoelectric element  31 . The glue overflow passages  35  are provided for extra glues to overflow therein in order to prevent the extra glues from flowing into the through holes  321  or affecting the nebulization effect. 
         [0052]    In other implementation modes, the shape and arrangement of the through holes  321  and the glue overflow passage  35  can be as shown in  FIGS. 16 to 18 . 
         [0053]    In one of the characteristics of the nebulization structure of the present invention, the nebulization plate is made of a polymer material instead, so that the metal nebulization plate can have a better stability and improve the chemical resistance. 
         [0054]    In another characteristic of the nebulization structure of the present invention, the rib formed between two adjacent through holes on the structure plate can support the nebulization plate and combine the nebulization plate closely, so that the oscillation frequency of the nebulization plate is close to the vibration frequency of the driving element. 
         [0055]    In a further characteristic of the nebulization structure of the present invention, the ribs formed on the structure plate can be used as a passage for transmitting vibration energy and the liquid to be nebulized. Compared with the prior art, the present invention can transmit energy and liquid to be nebulized to the whole area of the nebulization plate more effectively and efficiently, so as to improve the nebulization effect.