Abstract:
A keyboard device including a lower cover, an upper cover for covering the lower cover and a keyboard module is provided. The lower cover has a plurality of hook structures, and the keyboard module includes a plurality of key caps and a plurality of scissor-type connecting elements. The plurality of hook structures are connected with the plurality of scissor-type connecting elements, and the plurality of scissor-type connecting elements are connected with the plurality of key caps. As a result, the lower cover is able to connect with the plurality of key caps without an additional base plate such that the cost of the keyboard device can be decreased and the volume of the keyboard device can be reduced.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention generally relates to a computer peripheral input device, and more particularly to a keyboard device. 
       BACKGROUND OF THE INVENTION 
       [0002]    The common computer peripheral input devices comprise the mouse devices, the keyboard devices, trackball devices and so on, wherein the keyboard devices have attracted increasing attention by the users and the manufacturers of the input devices since they can be used for directly keying in letters and symbols into the computers. 
         [0003]    An external structure of a keyboard device is illustrated hereinafter. Referring to  FIG. 1 ,  FIG. 1  illustrates a schematic structural external view of a conventional keyboard device. There are a plurality of keys located on a surface of the conventional keyboard  1 , wherein those keys are categorized into common keys  101 , number keys  102 , function keys  103  and so on, and a user can press down any one of the keys by using his finger, so as to generate a corresponding signal to a computer and thus enable the computer to execute a key function corresponding to the key being pressed down. For example, the common keys  101  can be used for keying in symbols such as English letters, the number keys  102  can be used for keying in numbers, while the function keys  103  can be used for executing various functions such as F1 to F12 and so on. 
         [0004]    An internal structure of the keyboard device  1  is illustrated hereinafter. Referring to  FIG. 2 ,  FIG. 2  illustrates a schematic structural side view of a conventional keyboard device. The conventional keyboard device  1  comprises a lower cover  11 , an upper cover  12  and a keyboard module  13 . Herein, the lower cover  11  is capable of carrying the keyboard module  13  thereon, while the upper cover  12  covers on the lower cover  11  and connects with the lower cover  11 , and the keyboard module  13  is exposed by the upper cover  12 , wherein both of the lower cover  11  and the upper cover  12  are made of plastic material, and the upper cover  12  and the lower cover  11  are connected with each other by screwing them together with screws  14 . In addition, the keyboard module  13  is disposed on the lower cover  11  and comprises a plurality of key caps  131 , a plurality of scissor-type connecting elements  132 , a plurality of elastic elements  133 , a membrane switch circuit  134  and a base plate  135 . Herein, the base plate  135  is disposed on the lower cover  11 , and the base plate  135  has a plurality of fixing hooks  1351  and a plurality of sliding hooks  1352 , wherein the plurality of fixing hooks  1351  and the plurality of sliding hooks  1352  are formed integrally with the base plate  135 , and the base plate  135  is made of metal material. In addition, the membrane switch circuit  134  is disposed on the base plate  135  and capable of generating a plurality of key signals by being triggered. Moreover, the plurality of elastic elements  133  are disposed on the membrane switch circuit  134  and capable of triggering the membrane switch circuit  134  or providing a plurality of elastic forces to the plurality of key caps  131 , wherein the plurality of elastic elements  133  are made of rubber material. 
         [0005]    Besides, the plurality of scissor-type connecting elements  132  are located between the plurality of key caps  131  and the base plate  135 . In addition, each one of the plurality of scissor-type connecting elements  132  comprises a first frame  1321  and a second frame  1322 . With regards to the plurality of first frames  1321 , a first end (not shown) of each one of the plurality of first frames  1321  connects with a corresponding one of the plurality of key caps  131 , while a second end  1321 B of each one of the plurality of first frames  1321  connects with a corresponding one of the plurality of fixing hooks  1351 . In contrast, with regards to the plurality of second frames  1322 , a first end  1322 A of each one of the plurality of second frames  1322  connects with a corresponding one of the plurality of sliding hooks  1351 , while a second end (not shown) of each one of the plurality of second frames  1322  connects with a corresponding one of the plurality of key caps  131 . Hence, when any one of the plurality of key caps  131  exposed by the upper cover  12  is pressed down, the second frame  1322  corresponding to the key cap  131  is swung relative to the first frame  1321  corresponding to the key cap  131 , so as to enable the key cap  131  to be moved downward relative to the base plate  135 . At the same time, the key cap  131  pushes the corresponding one of the elastic elements  133 , and thus the elastic element  133  is compressed and triggers the membrane switch circuit  134 , so as to enable the membrane switch circuit  134  to generate the corresponding key signal. Here, the structures and the operations of the conventional keyboard device  1  are illustrated. 
         [0006]    However, all of the products today tend to become thinner and lighter, and thus the most important desired improvement to the keyboard manufacturers is trying to minimize and thin the keyboard device. In addition, another desired improvement to the keyboard manufacturers is the cost of the keyboard device. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention is directed to providing a keyboard device with a smaller volume. 
         [0008]    The present invention is further directed to providing a keyboard device with lower cost. 
         [0009]    In a preferred embodiment, the present invention provides a keyboard device, comprising: 
         [0010]    a lower cover, having a plurality of hook structures; 
         [0011]    an upper cover, covering the lower cover and connecting with the lower cover; and 
         [0012]    a keyboard module, disposed on the lower cover and exposed by the upper cover, and the keyboard module comprising:
       a plurality of key caps, located over the lower cover, exposed by the upper cover, and capable of being pressed down; and   plurality of scissor-type connecting elements, connecting between the plurality of key caps and the plurality of hook structures respectively, and capable of connecting the plurality of key caps with the lower cover, wherein each one of the plurality of key caps is capable of being moved downward relative to the lower cover when being pressed down and moved upward relative to the lower cover when being released.       
 
         [0015]    In a preferred embodiment, the plurality of hook structures and the lower cover are formed integrally. 
         [0016]    In a preferred embodiment, the plurality of hook structures and the lower cover are made of plastic material. 
         [0017]    In a preferred embodiment, the lower cover further comprises a plurality of openings, while the upper cover comprises a plurality of screw pillars corresponding to the plurality of openings, and the plurality of screw pillars contact with the plurality of openings when the upper cover covers the lower cover. 
         [0018]    In a preferred embodiment, the keyboard device of the present invention further comprises a plurality of screws, which are capable of passing through the plurality of openings and being screwed onto the plurality of screw pillars, so as to connect the lower cover with the upper cover. 
         [0019]    In a preferred embodiment, the keyboard device of the present invention further comprises: 
         [0020]    a membrane switch circuit, located below the plurality of scissor-type connecting elements, and capable of generating a plurality of key signals by being triggered; and 
         [0021]    a plurality of elastic elements, located between the plurality of key caps and the membrane switch circuit, wherein the plurality of elastic elements are passing through the plurality of scissor-type connecting elements, and capable of being pushed by the plurality of key caps, so as to trigger the membrane switch circuit, or capable of providing elastic forces to the plurality of key caps, so as to return the plurality of key caps. 
         [0022]    In a preferred embodiment, each one of the plurality of scissor-type connecting elements comprises: 
         [0023]    a first frame, wherein a second end of the first frame connecting with a first side of a corresponding one of the plurality of key caps, and a first end of the first frame connecting with a corresponding one of the plurality of hook structures; and 
         [0024]    a second frame, connecting with the first frame and capable of being swung relative to the first frame, wherein a first end of the second frame connecting with a corresponding one of the plurality of hook structures, and a second end of the second frame connecting with a second side of a corresponding one of the plurality of key caps. 
         [0025]    In a preferred embodiment, each one of the plurality of hook structures comprises: 
         [0026]    a fixing hook, disposed below a second side of a corresponding one of the plurality of key caps and capable of connecting with the first end of the corresponding one of the plurality of first frames, so as to enable the first end of the corresponding one of the plurality of first frames to be rotated relative to the fixing hook; and 
         [0027]    a sliding hook, disposed below a first side of a corresponding one of the plurality of key caps and capable of connecting with the first end of the corresponding one of the plurality of second frames, so as to enable the first end of the corresponding one of the plurality of second frames to be slid relative to the sliding hook. 
         [0028]    In a preferred embodiment, each one of the plurality of fixing hooks is formed as a close structure without any gap, while each one of the plurality of sliding hooks is formed as an open structure with a gap. 
         [0029]    In a preferred embodiment, each one of the plurality of fixing hooks and the plurality of sliding hooks is formed as an open structure with a gap, and a length of each one the plurality of sliding hooks is longer than a length of a corresponding one of the plurality of fixing hooks. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0030]      FIG. 1  illustrates a schematic structural external view of a conventional keyboard device. 
           [0031]      FIG. 2  illustrates a schematic structural side view of a conventional keyboard device. 
           [0032]      FIG. 3  illustrates a schematic structural side view of a keyboard device according to a first preferred embodiment of the present invention. 
           [0033]      FIG. 4  illustrates a schematic partial structural cross-sectional view of a keyboard device according to a first preferred embodiment of the present invention. 
           [0034]      FIG. 5  illustrates a schematic partial structural cross-sectional view of a keyboard device according to a second preferred embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0035]    Reference will now be made in detail to specific embodiments of the present invention. Examples of these embodiments are illustrated in the accompanying drawings. While the invention will be described in conjunction with these specific embodiments, it will be understood that it is not intended to limit the invention to these embodiments. In fact, it is intended to cover alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims. In the following description, numerous specific details are set forth in order to provide a through understanding of the present invention. The present invention may be practiced without some or all of these specific details. In other instances, well-known process operations are not described in detail in order not to obscure the present invention. 
         [0036]    The present invention provides a kind of keyboard device capable of improving the disadvantages of the conventional technology. Referring to  FIG. 3  and  FIG. 4  together,  FIG. 3  illustrates a schematic structural side view of a keyboard device according to a first preferred embodiment of the present invention, while  FIG. 4  illustrates a schematic partial structural cross-sectional view of a keyboard device according to a first preferred embodiment of the present invention. The keyboard device  2  comprises a lower cover  21 , an upper cover  22 , a keyboard module  23  and a plurality of screws  24  (there is only one screw illustrated in  FIG. 3 ), wherein the lower cover  21  has a plurality of hook structures  211  and a plurality of openings  212 . In the present preferred embodiment, the plurality of hook structures  211  and the plurality of openings  212  are formed integrally with the lower cover  21 , and the plurality of hook structures  211 , the plurality of openings  212  and the lower cover  21  are all made of plastic material. In addition, the upper cover  22  covers on the lower cover  21  and connects with the lower cover  21 , and the upper cover  22  has a plurality of screw pillars  221  corresponding to the plurality of openings  212 . When the upper cover  22  covers the lower cover  21 , the plurality of screw pillars  221  contact with the plurality of openings  212 , so as to enable the plurality of screws  24  to pass through the plurality of openings  212  and to be screwed onto the plurality of screw pillars  221 . As a result, the lower cover  21  is connected with the upper cover  22 . In the present preferred embodiment, the plurality of screw pillars  221  are integrally formed with the upper cover  22 . 
         [0037]    In addition, the keyboard module  23  is disposed on the lower cover  11  and partially exposed by the upper cover  22 , wherein the keyboard module  23  comprises a plurality of key caps  231 , a plurality of scissor-type connecting elements  232 , a plurality of elastic elements  233  and a membrane switch circuit  234 . Herein, the plurality of key caps  231  are located over the lower cover  21 , exposed by the upper cover  22 , and capable of being pressed down. The plurality of scissor-type connecting elements  232  connect between the plurality of key caps  231  and the plurality of hook structures  211  respectively, and are capable of connecting the plurality of key caps  231  with the lower cover  21 . In addition, when a key cap  231  is pressed down, a corresponding scissor-type connecting element  232  is activated, so as to enable the key cap  231  to be moved downward relative to the lower cover  21 . Moreover, each one of the plurality of scissor-type connecting elements  232  comprises a first frame  2321  and a second frame  2322 , wherein a second end  2321 B of the first frame  2321  connects with a first side  2311  of the corresponding one of the plurality of key caps  231  corresponding to the second end  2321 B thereof, and a first end  2321 A of the first frame  2321  connects with one of the plurality of hook structures  211  corresponding to the second end  2322  thereof. In contrast, the second frame  2322  connects with the first frame  2321  and is capable of being swung relative to the corresponding first frame  2321 , wherein a first end  2322 A of the second frame  2322  connects with one of the plurality of hook structures  211  corresponding to the first end  2322 A thereof, and a second end  2322 B of the second frame  2322  connects with a second side  2312  of one of the plurality of key caps  231  corresponding to the second end  2322 B thereof. 
         [0038]    Furthermore, the membrane switch circuit  234  is located below the plurality of scissor-type connecting elements  232 , and capable of generating a plurality of key signals by being triggered. In addition, the plurality of elastic elements  233  are located between the plurality of key caps  231  and the membrane switch circuit  234 , passes through the plurality of scissor-type connecting elements  232 , and capable of being pushed by the plurality of key caps  231 , so as to trigger the membrane switch circuit  234 , or capable of providing elastic forces to the plurality of key caps  231 , so as to return the plurality of key caps  231  to the locations before being pressed down. Here, a key cap  231 , a scissor-type connecting element  232 , an elastic element  233  and a part of the membrane switch circuit  234  of the keyboard module  23  are formed as a key together. In the present preferred embodiment, the plurality of elastic elements  233  are made of rubber material, and each one of the plurality of elastic elements  233  corresponds to one of the plurality of key caps  231  and one of the plurality of scissor-type connecting elements  232 . In contrast, in another preferred embodiment, the plurality of elastic elements  233  are made of metal material, and the plurality of elastic elements  233  are disposed on an elastic layer, i.e. the plurality of elastic elements  233  are formed integrally with the elastic layer. 
         [0039]    In the lower cover  21 , each one of the plurality of hook structures  211  comprises a fixing hook  2111  and a sliding hook  2112 , wherein the fixing hook  2111  is disposed below the second side  2312  of the corresponding one of the plurality of key caps  231  and capable of connecting with the first end  2121 A of the corresponding one of the plurality of first frames  2121 , so as to enable the first end  2121 A of the corresponding one of the plurality of first frames  2121  to be rotated relative to the fixing hook  2111 . In contrast, the sliding hook  2112  is disposed below the first side  2311  of the corresponding one of the plurality of key caps  231  and capable of connecting with the second end  2322 B of the corresponding one of the plurality of second frames  2322 , so as to enable the second end  2322 B of the corresponding one of the plurality of second frames  2322  to be slid relative to the sliding hook  2112 . In the present preferred embodiment, each one of the plurality of hook structures  211  corresponds to one of the scissor-type connecting elements  232 , each one of the plurality of fixing hooks  2111  and the plurality of sliding hooks  2112  is formed as an open structure with a gap, and a length L 2  of each one the plurality of sliding hooks  2112  is longer than a length L 1  of a corresponding one of the plurality of fixing hooks  2111 . Here, the open structure means a hook with a gas as illustrated in  FIG. 4 . 
         [0040]    In detail, when the user presses down any one key cap  231  of the plurality of key caps  231 , the pressed key cap  231  is moved downward relative to the lower cover  21 , and the corresponding second frame  2322  is swung relative to the corresponding first frame  2321 . At the same time, the first end  2321 A of the first frame  2321  is rotated relative to the corresponding fixing hook  2111 , and the first end  2322 A of the second frame  2322  is slid relative to the corresponding sliding hook  2312 , so as to enable the pressed key cap  231  to push the corresponding elastic element  233 . As a result, the elastic element  233  is compressed, accumulates an elastic force, and triggers the membrane switch circuit  234 , so as to enable the membrane switch circuit  234  to output a corresponding key signal. In contrast, when the user releases the pressed key cap  231 , the compressed elastic element  233  releases the elastic force to the pressed key cap  231 , so as to enable the pressed key cap  231  to be moved upward relative to the lower cover  21 , and the second frame  2322  is swung relative to the first frame  2321 . At the same time, the first end  2321 A of the first frame  2321  is rotated relative to the fixing hook  2111 , and the first end  2322 A of the second frame  2322  is slid relative to the sliding hook  2312 , so as to return the pressed key cap  231 . 
         [0041]    In addition, the present invention provides a second preferred embodiment as well. Referring to  FIG. 5 ,  FIG. 5  illustrates a schematic partial structural cross-sectional view of a keyboard device according to a second preferred embodiment of the present invention. The keyboard device comprises a lower cover  31 , an upper cover (not shown), a keyboard module and a plurality of screws (not shown), wherein the lower cover  31  has a plurality of hook structures  311  and a plurality of openings (not shown), while the upper cover has a plurality of screw pillars (not shown) corresponding to the plurality of openings. Further, the keyboard module comprises a plurality of key caps  331 , a plurality of scissor-type connecting elements  332 , a plurality of elastic elements  333  and a membrane switch circuit  334 . Most of the structures of the keyboard device of the present preferred embodiment are substantially the same as those of the keyboard device  2  of the foregoing first preferred embodiment and thus are omitted herein. 
         [0042]    In a word, the structures of the present preferred embodiment different from those of the first preferred embodiment include at least two points. First, each one of the hook structures  311  comprises a fixing hook  3111  and a sliding hook  3112 , wherein the fixing hook  3111  is disposed below a second side  3312  of the corresponding one of the plurality of key caps  331 , and capable of connecting with a first end  3321 A of a first frame  3321  of the corresponding one of the plurality of scissor-type connecting elements  332 , so as to enable the first end  3321 A of the first frame  3321  to be rotated relative to the fixing hook  3111 , while the sliding hook  3112  is disposed below a first side  3311  of the corresponding one of the plurality of key caps  331 , and capable of connecting with a first end  3322 A of a second frame  3322  of the corresponding one of the plurality of scissor-type connecting elements  332 , so as to enable the first end  3322 A of the second frame  3322  to be slid relative to the sliding hook  3112 . In the present preferred embodiment, the fixing hook  3111  is formed as a close structure without any gap, while the sliding hook  3112  is formed as an open structure with a gap. 
         [0043]    It should be noted that all of the key caps, the scissor-type connecting elements, the elastic elements and the hook structures descried in the present invention are one-to-one correspondence. However, it should be understood that, in the present invention, the key caps, the scissor-type connecting elements, the elastic elements and the hook structures are not limited to one-to-one correspondence. In another word, in the keyboard device of the present invention, part of the keys can connect with the key caps and the lower cover via the scissor-type connecting elements, and the other part of the keys can connect with the key caps and the lower cover by using other manners, wherein the other manners are well known to those of skilled in the art and thus are omitted herein. 
         [0044]    Based upon the descriptions of each of the preferred embodiments illustrated above, it should be understood that not only the plurality of hook structures of the base plate in the related art are disposed on the lower cover in the present invention but also the plurality of hook structures are connected with the plurality of scissor-type connecting elements, so as to enable the lower cover to be connected with the plurality of scissor-type connecting elements directly. In another word, since it is no more need to dispose a base plated in the keyboard device, a total thickness of the keyboard device of the present invention can be reduced, and thus a total volume of the keyboard device can be reduced accordingly as well, wherein the reduced thickness is substantially equal to the thickness of the base plate. In the other hand, the cost of the keyboard device of the present invention can be reduced as well since it is no more need to dispose a base plated in the keyboard device. 
         [0045]    Although specific embodiments of the present invention have been described, it will be understood by those of skill in the art that there are other embodiments that are equivalent to the described embodiments. Accordingly, it is to be understood that the invention is not to be limited by the specific illustrated embodiments, but only by the scope of the appended claims.