Abstract:
A keyswitch and a keyboard are provided. A top plate of a keycap of the keyswitch, for being pressed and decoration, and a frame including groove bodies, for linking with a supporting mechanism, are separated into two components such that the top plate may be implemented as a plate structure with much thinner thickness while maintaining its strength, and the frame with the groove bodies is attached to the top plate via insert molding or adhering. The frame and the top plate form the keycap, in which the groove bodies at the frame and the top plate form sliding slots or engaging slots in cooperation with the supporting mechanism. The thickness of the keycap can be substantially reduced and meanwhile maintain the necessary stroke of the keyswitch and the strength of the keycap. The keyboard having the keyswitches is made possible for further miniaturized with thinner thickness.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to an input device, and more particularly to a keyswitch and a keyboard having a plurality of the keyswitches, wherein the keyswitch has a keycap with a thin top plate. 
       BACKGROUND OF THE INVENTION 
       [0002]    When using a personal computer, a keyboard for inputting characters, symbols or numerals is one of the indispensable input devices. Moreover, for all of the consumer electronic products in the daily life or large-scale processing devices used in the industry, a keyswitch structure is used as an input device for operating the electronic products or processing devices. 
         [0003]    Please refer to  FIG. 1 , which shows a schematic diagram of a keyswitch  1  of the prior art. As shown in  FIG. 1 , the keyswitch  1  includes a keycap  10 , a supporting mechanism  12  with a shape like scissors, and a base plate  14 . The supporting mechanism  12  includes two supports  120 ,  122 . The supports  120 ,  122  are attached between the keycap  10  and the base plate  14 , respectively, for supporting the keycap  10 . The keycap  10  can move vertically relative to the base plate  14  with the movement of the supporting mechanism  12 . 
         [0004]    As shown in  FIG. 1 , a keycap  10  includes a top plate  100 , two engaging slots  102  and two sliding slots  104 . The engaging slots  102  and the sliding slots  104  can engage with the supports  120 ,  122 , respectively. Generally speaking, the keycap  10  can be formed by injection molding so that the top plate  100 , the engaging slots  102  and the sliding slots  104  are integrally formed. Since the injection molding technique is used, and the engaging slots  102  and the sliding slots  104  must be formed on the top plate  100 , the keycap  10  may be formed of plastic materials. However the strength of plastic keycap  10  becomes weak if one wants to make the keycap  10  thinner. 
       SUMMARY OF THE INVENTION 
       [0005]    In order to solve the above problem, the invention provides a keyswitch, including a keycap, a base plate and a supporting mechanism. The keycap includes a top plate and a frame. The frame is attached on a side of the top plate, and is a hollow structure. The supporting mechanism is disposed between the keycap and the base plate. 
         [0006]    The invention also provides a keyboard, including a base plate and a plurality of keyswitches. The plurality of keyswitches is disposed on the base plate, wherein any one of the keyswitches includes a keycap and a supporting mechanism. The keycap includes a top plate and a frame. The frame is attached on a side of the top plate, and is a hollow structure. The supporting mechanism is disposed between the keycap and the base plate. 
         [0007]    In an embodiment of the invention, the top plate is a plate structure with a thickness smaller than or equal to 0.4 millimeter, and the top plate is made of stainless-steel, aluminum or plastic material. 
         [0008]    In an embodiment of the invention, the frame is attached to the side of the top plate via insert molding. 
         [0009]    In an embodiment of the invention, the frame has a frame body, a first groove body and a second groove body, the first groove body and the second groove body are disposed on a side of the frame body, the first groove body extends on a corner between adjacent sides of the frame body or on one of the sides, and the second groove body extends on a corner between adjacent sides of the frame body or on one of the sides. The first groove body and the second groove body are L-shaped. 
         [0010]    In an embodiment of the invention, the first groove body and the top plate form a first sliding slot, the second groove body and the top plate form a second sliding slot, the base plate has a base plate sliding slot and a base plate engaging slot, the supporting mechanism includes a first lever and a second lever. The first lever has a first sliding portion and a first pivoting portion, the first sliding portion is slidably disposed in the first sliding slot, while the first pivoting portion is rotatably pivoted in the base plate engaging slot. The second lever and the first lever are pivoted with each other, the second lever has a second sliding portion and a third sliding portion, the second sliding portion is slidably disposed in the second sliding slot, while the third sliding portion is slidably disposed in the base plate sliding slot. 
         [0011]    In an embodiment of the invention, the first groove body and the top plate form a first sliding slot, the second groove body and the top plate form a first engaging slot, the base plate has a base plate sliding slot and a base plate engaging slot, the supporting mechanism includes a first lever and a second lever. The first lever has a first sliding portion and a first pivoting portion, the first sliding portion is slidably disposed in the first sliding slot, while the first pivoting portion is rotatably pivoted in the base plate engaging slot. The second lever and the first lever are pivoted with each other, the second lever has a second sliding portion and a second pivoting portion, the second sliding portion is slidably disposed in the base plate sliding slot, while the second pivoting portion is rotatably pivoted in the first engaging slot. 
         [0012]    In the keyswitch and keyboard of the invention, the keycap of each keyswitch is separated into a top plate and a frame, so that the top plate can be made by using metal or other material that can be easily made to have a plate shape. The thickness of the top plate of the keycap can be substantially reduced and meanwhile the necessary stroke of the keyswitch and the strength of the keycap are maintained. The keyboard with such structure is made possible for further miniaturized with thinner thickness in order to comply with the requirements of the miniaturized electronic devices. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    The present invention will become more readily apparent to those ordinarily skilled in the art after reviewing the following detailed description and accompanying drawings, in which: 
           [0014]      FIG. 1  is a schematic diagram showing a keyswitch of the prior art. 
           [0015]      FIG. 2  is a schematic diagram showing a keyboard of an embodiment of the invention. 
           [0016]      FIG. 3  is an exploded view drawing showing components of a keyswitch of an embodiment of the invention. 
           [0017]      FIG. 4  is schematic diagram showing a keycap of the keyswitch of  FIG. 3 . 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0018]    The present invention will now be described more specifically with reference to the following embodiments. It is to be noted that the following descriptions of preferred embodiments of this invention are presented herein for purpose of illustration and description only. It is not intended to be exhaustive or to be limited to the precise form disclosed. 
         [0019]    Please refer to  FIG. 2 , which is a schematic diagram showing a keyboard of an embodiment of the invention. The keyboard  3  has a plurality of keyswitches  30  and a base plate  34 . The keyswitches  30  of the keyboard  3  are disposed on the base plate  34 . The keyswitches  30  can be mechanical keyswitches or membrane keyswitches. In the keyswitch  30 , a scissors type supporting mechanism is used. 
         [0020]    Please refer to  FIG. 3 , which is an exploded view drawing showing components of the keyswitch  30  of the embodiment of the invention. The keyswitch  30  includes a keycap  40 , a base plate  34 , an elastic member  50  and a supporting mechanism  32 . The keycap  40  is disposed on the base plate  34 , and the supporting mechanism  32  is disposed between the keycap  40  and the base plate  34 . The supporting mechanism  32  supports a vertical movement of the keycap  40 , and enables the keycap  40  to move vertically downward relative to the base plate  34  when the keycap  40  is pressed. After that, the keycap  40  can be returned upwardly by the elastic member  50 . 
         [0021]    The supporting mechanism  32  preferably has a scissors-like structure. In another embodiment, the supporting mechanism  32  can has other structure to support the keycap  40 . The supporting mechanism  32  includes a first lever  321  and a second lever  322 . The first lever  321  has an upper end, a lower end, and pivot axes  325 . The upper end includes first sliding portions  324 , and the lower end includes first pivoting portions  323 . The second lever  322  has an upper end, a lower end, and pivot grooves  328 . The upper end includes second sliding portions  326 , and the lower end includes third sliding portions  327 . The first lever  321  and the second lever  322  pivot with each other by the pivot axes  325  and the pivot grooves  328 . The base plate sliding slots  343  and base plate engaging slots  342  are formed on the base plate  34  in corresponding to the supporting mechanism  32 . The first pivoting portions  323  of the first lever  321  are rotatably pivoted in the base plate engaging slots  342 , while the third sliding portions  327  of the second lever  322  are slidably and rotatably received within the base plate sliding slots  343 . Therefore, when the keycap  40  is pressed to move down the supporting mechanism  32 , the first pivoting portions  323  rotate in the base plate engaging slots  342 , while the third sliding portions  327  rotatably slide in the base plate sliding slots  343 . The elastic member  50  is disposed through the first lever  321  and the second lever  322  and abuts the keycap  40 . 
         [0022]    In the embodiment of the invention, the keycap  40  includes a top plate  42  and a frame  44 . The top plate  42  and the frame  44  are two independent components, which can be manufactured separately, and can be made by the same or different materials or manufacturing methods. The top plate  42  of the keycap  40  is a plate structure. In the embodiment of the invention, the top plate  42  can be made of stainless-steel, aluminum or plastic material. When maintaining strength of the top plate  42 , the thickness of the top plate  42  can be controlled to be smaller than or equal to 0.4 millimeter, and preferably between 0.2 millimeter and 0.4 millimeter. 
         [0023]    The frame  44  is attached on a side of the top plate  42 . The frame  44  can be attached to the top plate  42  via adhering or insert molding. In the embodiment of the invention, the frame  40  is a rectangular-shaped structure having a frame opening  449  at its center, and the elastic member  50  abuts a lower surface of the top plate  42  through the frame opening  449 . The frame  44  is a hollow structure, which has a hollow frame body  440 , first groove bodies  441  and second groove bodies  442 . The frame  44  constitutes a portion of a linking structure for cooperation with the supporting mechanism  32 . As shown in  FIG. 3 , the first groove bodies  441  and the second groove bodies  442  are disposed on side walls  445 ,  446  of the frame body  440 , respectively. In this embodiment, the first groove bodies  441  extend on the side wall  445  or on the corners between the side wall  445  and the side walls  447 ,  448 , while the second groove bodies  442  extend on the side wall  446  or on the corners between the side wall  446  and the side walls  447 ,  448 . The first groove body  441  has a first upward opening, and the second groove body  442  has a second upward opening In another embodiment, the frame may be a loop-shaped structure with a frame opening at its center. The upper surfaces of the four side walls  445 ,  446   447 ,  448  are higher than the upper surface of the first groove bodies  441  and the second groove bodies  442 . 
         [0024]    Please also refer to  FIG. 4 , which is a schematic diagram showing the keycap  40  of  FIG. 3 . As shown in  FIG. 4 , when the top plate  42  of the keycap  40  is linked with the frame  44  to form an integral structure, the top plate  42  seals the first and second upward openings. Such that, first position-limiting spaces such as first sliding slots  443  are formed between the first groove bodies  441  of the frame  44  and the top plate  42 , and second position-limiting spaces such as second sliding slots  444  are formed between the second groove bodies  442  and the top plate  42 . The first sliding slots are, for example, horizontally extended. In this embodiment, since the first groove bodies  441  and the second groove bodies  442  are L-shaped structures extending on the side walls  445 ,  446  of the frame body  440 , the first sliding slots  443  and the second sliding slots  444  formed therebetween with the top plate  42  provide places to slidably dispose the first lever  321  and the second lever  322  of the supporting mechanism  32 . More specifically, the first sliding portions  324  of the first lever  321  of the supporting mechanism  32  are movably received in the first sliding slots  443 , while the second sliding portions  326  of the second lever  322  are movably received in the second sliding slots  444 . When the keycap  40  is pressed to move down the supporting mechanism  32 , the first sliding portions  324  slide in the first sliding slots  443 , while the second sliding portions  326  slide in the second sliding slots  444 . 
         [0025]    Except the embodiment shown in  FIG. 3 , in other embodiments of the invention, the two levers of the supporting mechanism  32  can be respectively linked with the base plate  34  and the keycap  40  by different combinations of sliding portions with sliding slots, or pivoting portions with engaging slots. For example, for the second groove bodies  442  on the frame  44  of the keycap  40 , the structure of the second groove bodies  442  extending on the frame body  440  can also form first engaging slots with the top plate  42 , while the cooperating second levers  322  can have second pivoting portions to rotatably pivot in the first engaging slots. When the keycap  40  is pressed to move down the supporting mechanism  32 , the first sliding portions  324  of the first lever  321  slide in the first sliding slots  443 , while the second pivoting portions of the second lever  322  rotate in the first engaging slots of the keycap  40 . In another embodiment, the first position-limiting space may be a pivot groove, and the upper end of the first lever is rotatably connected to the first position-limiting space. In addition, in the embodiment shown in  FIG. 3 , the first groove bodies  441  and the second groove bodies  442  are all disposed on the corners of the frame body  440  so that the openings of the first groove bodies  441  face each other, and the openings of the second groove bodies  442  face each other. Thus, the corresponding first sliding portions  324  and second sliding portions  326  are formed as pillar structures protruding outwardly as shown in the  FIG. 3 . However, the first groove bodies  441  or the second groove bodies  442  can also be disposed on the corresponding side wall  445  or  446  away from the corners, so that the openings of the first groove bodies  441  (or the second groove bodies  442 ) can face the side wall  447  and the side wall  448 , respectively. Thus, the corresponding first sliding portions  324  and second sliding portions  326  are formed as pillar structures protruding inwardly. Although several possible aspects are listed on the above, other modified aspects can also be adapted without further description here. 
         [0026]    For the keyswitch and the keyboard having those keyswitches of the invention, the keycap is formed by two separated components: the top plate and the frame. The top plate normally is decorated with character or symbol, and a user finger can touch the top plate to press down the keyswitch. The frame includes groove bodies which constitute portions of the linking structures for cooperation with the supporting mechanism. The top plate may be made of the material which is stronger than the material of the frame, and shaped as a plate structure, so its thickness is dramatically reduced while maintaining its strength substantially the same. The frame with the groove bodies is then attached to the top plate via insert molding or adhering, so the groove bodies and the top plate form sliding slots or engaging slots in cooperation with the supporting mechanism. The thickness of the keycap can be dramatically reduced and the strength of the keycap are maintained the same. Therefore, the thickness of the keyswitch with such keycap structure is also reduced. 
         [0027]    While the invention has been described in terms of what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention needs not be limited to the disclosed embodiment. On the contrary, it is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims which are to be accorded with the broadest interpretation so as to encompass all such modifications and similar structures.