Patent Publication Number: US-8975547-B2

Title: Keyswitch and keyboard including the same

Description:
RELATED APPLICATIONS 
     This application claims priority to Taiwan Patent Application Serial Number 101211636, filed Jun. 15, 2012, which is herein incorporated by reference. 
     BACKGROUND 
     1. Technical Field 
     The present disclosure relates to a keyswitch and a keyboard including the keyswitch. 
     2. Description of Related Art 
     A keyboard is an essential input device for inputting characters or numbers when using a personal computer. Consumer electronics used in daily life or large-scale processing equipment used in industry need input devices having keyswitch structures for operating the consumer electronics products and the processing equipment. Known keyswitch structures are generally classified into dome switches and rubber switches. 
     In order to balance the force that a user applies onto a keyswitch of a keyboard, a scissors-like supporting structure is typically disposed under a keycap of the keyswitch for guiding the keycap to move vertically. Therefore, the force can be evenly distributed on the keycap, regardless of whether the force is applied at an edge or a corner of the keycap, so that the keyswitch can be easily pressed and operated by the user. 
     Furthermore, a screen-printing technique is used to print characters on a conventional keyboard. However, the raw materials used in such printing cause environmental problems. Moreover, after long-term use, the printed characters become worn and are not easily recognized. To allow visibility when working in dark places, keyboards having LED (light-emitting diode) backlights have been developed. A known configuration involves disposing each of the keyswitches of the keyboard (or each of the keyswitches thereof requiring visibility) on a light emitting-diode. 
     However, because the conventional illuminated keyboard includes structural components (e.g., a keycap, a scissors-like supporting structure, a linkage, etc.) provided in a stacked configuration, the problem of light leakage must be considered. In addition, the energy consumption and costs increase with the high number of light emitting-diodes used in such a conventional illuminated keyboard. Furthermore, the structural stacked components in the conventional keyboard are symmetric, and such a configuration blocks the light emitted from the light emitting-diodes that is directed toward the patterns on the keycaps, and thus the patterns are not easily recognized. 
     SUMMARY 
     In order to solve the problems of the prior art, the disclosure provides an improved keyswitch. The keyswitch adopts an asymmetric scissors-like supporting structure to provide support under a keycap, so that a certain portion (e.g., a corner of the keycap) is not occupied by the scissors-like supporting structure. Accordingly, the light emitted by a light source that is disposed at the bottom of the keyswitch is not obscured by the scissors-like supporting structure and can be transmitted to a pattern of a laser inside-engraving layer in a light pervious region of the keycap. Therefore, the display result of the pattern is visually appealing and easily recognized by users. Because the keyswitch adopts the asymmetric scissors-like supporting structure, the disclosure further improves the stability of the keycap during vertical movement by increasing the thickness of the keycap and the thickness of the scissors-like supporting structure, and additionally by disposing a linkage member for providing additional support to the keycap. 
     According to an embodiment of the disclosure, a keyswitch is disposed on a base plate. The keyswitch includes a keycap and a scissors-like supporting structure. The scissors-like supporting structure is disposed on the base plate and supports the keycap. The scissors-like supporting structure includes a first supporting member and a second supporting member. The first supporting member includes a first engaging shaft and a second engaging shaft. The first engaging shaft and the second engaging shaft are respectively engaged with the base plate and the keycap. A line connected between the centers of gravity of the first engaging shaft and second engaging shaft is not perpendicular to the axial direction of the first engaging shaft and the axial direction of the second engaging shaft. The second supporting member is pivotally connected to the first supporting member and includes a third engaging shaft and a fourth engaging shaft. The third engaging shaft and the fourth engaging shaft are respectively engaged with the base plate and the keycap. A line connected between the centers of gravity of the third engaging shaft and fourth engaging shaft is not perpendicular to the axial direction of the third engaging shaft and the axial direction of the fourth engaging shaft. 
     In an embodiment of the disclosure, the length of the first engaging shaft is larger than the length of the second engaging shaft. The length of the fourth engaging shaft is larger than the length of the third engaging shaft. 
     In an embodiment of the disclosure, the keycap has a light pervious region. Both of the first supporting member and the second supporting member have an inwardly recessed shape at a location corresponding to the light pervious region. 
     In an embodiment of the disclosure, the keycap has a light pervious region. The length of the third engaging shaft is smaller than the length of the first engaging shaft, and the third engaging shaft is closer to the light pervious region than the first engaging shaft. The length of the second engaging shaft is smaller than the length of the fourth engaging shaft, and the second engaging shaft is closer to the light pervious region than the fourth engaging shaft. 
     In an embodiment of the disclosure, a thickness of the keycap is larger than 1 mm. 
     In an embodiment of the disclosure, a thickness of the scissors-like supporting structure is larger than 1.3 mm. 
     In an embodiment of the disclosure, the keyswitch further includes a linkage member. The linkage member is engaged with the base plate and an edge of the keycap. 
     In an embodiment of the disclosure, the keycap comprises a laser inside-engraving layer, and the laser inside-engraving layer is located at the light pervious region. 
     In an embodiment of the disclosure, the laser inside-engraving layer includes a pattern, and the pattern is a number, a symbol, a word, or a graph. 
     The disclosure further provides an improved keyboard. The keyboard disposes a light source under a keycap, and the light emitted by the light source is not obscured by a scissors-like supporting structure and can be transmitted to a pattern of a laser inside-engraving layer in a light pervious region of the keycap, so that the display result of the pattern is visually appealing and easily recognized by users. 
     According to an embodiment of the disclosure, a keyboard includes a base plate, a light source, and a plurality of keyswitches. The base plate has a plurality of holes. The light source is disposed under the base plate, and is used for emitting light via the holes. The keyswitches are disposed on the base plate. Each of the keyswitches includes a keycap and a scissors-like supporting structure. The keycap has a light pervious region corresponding to the light source. The scissors-like supporting structure is disposed on the base plate and supports the keycap. The scissors-like supporting structure includes a first supporting member and a second supporting member. The first supporting member includes a first engaging shaft and a second engaging shaft. The first engaging shaft and the second engaging shaft are respectively engaged with the base plate and the keycap. A line connected between the centers of gravity of the first engaging shaft and second engaging shaft is not perpendicular to the axial direction of the first engaging shaft and the axial direction of the second engaging shaft. The second supporting member is pivotally connected to the first supporting member and includes a third engaging shaft and a fourth engaging shaft. The third engaging shaft and the fourth engaging shaft are respectively engaged with the base plate and the keycap. A line connected between the centers of gravity of the third engaging shaft and fourth engaging shaft is not perpendicular to the axial direction of the third engaging shaft and the axial direction of the fourth engaging shaft. 
     It is to be understood that both the foregoing general description and the following detailed description are by examples, and are intended to provide further explanation of the disclosure as claimed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosure can be more fully understood by reading the following detailed description of the embodiment, with reference made to the accompanying drawings as follows: 
         FIG. 1  is a perspective view of a keyboard according to an embodiment of the disclosure; 
         FIG. 2  is a top view of a keyswitch in  FIG. 1 , in which the contour of a base plate is indicated by dotted lines; 
         FIG. 3  is a partial top view of the base plate in  FIG. 1 ; 
         FIG. 4  is a top view of a keycap of the keyswitch in  FIG. 1 ; 
         FIG. 5  is an exploded view of a scissors-like supporting structure of the keyswitch in  FIG. 1 ; 
         FIG. 6  is an assembled view of the scissors-like supporting structure in  FIG. 5 ; 
         FIG. 7  is a top view of a portion of the base plate and the scissors-like supporting structure of the keyswitch in  FIG. 1 ; 
         FIG. 8  is another top view of the keyswitch in  FIG. 1 , in which the scissors-like supporting structure is indicated by dotted lines; and 
         FIG. 9  is another top view of the keyswitch in  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to the present embodiments of the disclosure, 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. 
       FIG. 1  is a perspective view of a keyboard  1  according to an embodiment of the disclosure. 
     As shown in  FIG. 1 , the keyboard  1  of the disclosure can be an external keyboard (e.g., a keyboard with a PS/2 interface or a keyboard with a USB interface) used in a desktop computer, or can be a part of a computer system having an input device that is in the form of a keyboard (e.g., a notebook computer or a laptop computer), but the disclosure is not limited in this regard. That is, the keyboard  1  of the disclosure can be used in any electronic product that adopts keyswitches to be the input interface. In particular, the concepts of the disclosure can be used in keyboards having scissors-like supporting structures. 
     As shown in  FIG. 1 , the keyboard  1  includes at least a base plate  10  and a plurality of keyswitches  14 . The structures of components included in the keyboard  1  and connection relationships among the components are described in detail below. 
       FIG. 2  is a top view of one of the keyswitches  14  in  FIG. 1 , in which the contour of a base plate  10  is indicated by dotted lines. 
     As shown in  FIG. 2 , the base plate  10  of the keyboard  1  has a hole  100 . The keyboard  1  further includes a light source  12 , and the light source  12  is disposed at an appropriate location under a keycap  140  for emitting light toward the keycap  140 . The light source  12  can be located above or under the base plate  10 . In the embodiment of the disclosure, the light source  12  of the keyboard  1  is disposed under the base plate  10  and emits light via the hole  100  of the base plate  10 . The keyswitch  14  includes the keycap  140 , and a corner of the keycap  140  has a light pervious region  140   a  (i.e., the lower left corner of the keycap  140  in  FIG. 2  has the light pervious region  140   a ). The light pervious region  140   a  is aligned with the light source  12  which is disposed under the hole  100  of the base plate  10 . 
       FIG. 3  is a partial top view of the base plate  10  in  FIG. 1 .  FIG. 4  is a top view of the keycap  140  of the keyswitch  14  in  FIG. 1 . 
     As shown in  FIG. 3 , the base plate  10  of the keyboard  1  includes a first lower engaging portion  102  and a second lower engaging portion  104 . The first lower engaging portion  102  and the second lower engaging portion  104  of the base plate  10  are substantially arranged along a direction. As shown in  FIG. 4 , the bottom of the keycap  140  of the keyswitch  14  includes a first upper engaging portion  140   b  and a second upper engaging portion  140   c.  The first upper engaging portion  140   b  and the second upper engaging portion  140   c  of the keycap  140  are substantially arranged along a direction. 
       FIG. 5  is an exploded view of a scissors-like supporting structure  142  of the keyswitch  14  in  FIG. 1 .  FIG. 6  is an assembled view of the scissors-like supporting structure  142  in  FIG. 5 . 
     As shown in  FIG. 5  and  FIG. 6 , each of the keyswitches  14  of the keyboard  1  further includes a scissors-like supporting structure  142 . The scissors-like supporting structure  142  of the keyswitch  14  is disposed on the base plate  10  of the keyboard  1  and supports the keycap  140  of the keyswitch  14 . The scissors-like supporting structure  142  of the keyswitch  14  includes a first supporting member  142   a  and a second supporting member  142   b.  Both the first supporting member  142   a  and the second supporting member  142   b  of the scissors-like supporting structure  142  are roughly circular in shape, and the shape and size of the first supporting member  142   a  are such that the first supporting member  142   a  follows along and surrounds the periphery of the second supporting member  142   b  (i.e., the size of the first supporting member  142   a  is larger than the size of the second supporting member  142   b ). The first supporting member  142   a  of the scissors-like supporting structure  142  has two coaxial pivotal holes  142   a   3 , and the pivotal holes  142   a   3  are respectively located at inner walls of two opposite edges of the first supporting member  142   a . The second supporting member  142   b  of the scissors-like supporting structure  142  has two coaxial pivotal rods  142   b   3 , and the pivotal rods  142   b   3  are respectively located at outer walls of two opposite edges of the second supporting member  142   b.  When the first supporting member  142   a  surrounds the periphery of the second supporting member  142   b , the pivotal holes  142   a   3  of the first supporting member  142   a  can be pivotally connected with the pivotal rods  142   b   3  of the second supporting member  142   b  (i.e., the pivotal holes  142   a   3  of the first supporting member  142   a  and the pivotal rods  142   b   3  of the second supporting member  142   b  are coaxial after assembly). Therefore, the second supporting member  142   b  with a smaller size can rotate at the inner edge of the first supporting member  142   a.    
     As shown in  FIG. 5  and also in  FIG. 3  and  FIG. 4 , the first supporting member  142   a  of the scissors-like supporting structure  142  includes a first engaging shaft  142   a   1  and a second engaging shaft  142   a   2 , and the first engaging shaft  142   a   1  and the second engaging shaft  142   a   2  are respectively located at the upper side and the lower side of the first supporting member  142   a . The first engaging shaft  142   a   1  of the first supporting member  142   a  can be engaged with the first lower engaging portion  102  of the base plate  10 , and the second engaging shaft  142   a   2  of the first supporting member  142   a  can be engaged with the first upper engaging portion  140   b  of the keycap  140 . Furthermore, the second supporting member  142   b  of the scissors-like supporting structure  142  includes a third engaging shaft  142   b   1  and a fourth engaging shaft  142   b   2 , and the third engaging shaft  142   b   1  and the fourth engaging shaft  142   b   2  are respectively located at the upper side and the lower side of the second supporting member  142   b.  The third engaging shaft  142   b   1  of the second supporting member  142   b  can be engaged with the second lower engaging portion  104  of the base plate  10 , and the fourth engaging shaft  142   b   2  of the second supporting member  142   b  can be engaged with the second upper engaging portion  140   c  of the keycap  140 . 
     In order to ensure that the keycap  140  can vertically move relative to the base plate  10  when the keyswitch  14  is pressed, the first engaging shaft  142   a   1  of the first supporting member  142   a  and the fourth engaging shaft  142   b   2  of the second supporting member  142   b  are slidably engaged with the first lower engaging portion  102  of the base plate  10  and the second upper engaging portion  140   c  of the keycap  140  respectively, and the second engaging shaft  142   a   2  of the first supporting member  142   a  and the third engaging shaft  142   b   1  of the second supporting member  142   b  are pivotally connected to the first upper engaging portion  140   b  of the keycap  140  and the second lower engaging portion  104  of the base plate  10  respectively. 
     Alternatively, in another embodiment of the disclosure, the first engaging shaft  142   a   1  of the first supporting member  142   a  and the fourth engaging shaft  142   b   2  of the second supporting member  142   b  are pivotally connected to the first lower engaging portion  102  of the base plate  10  and the second upper engaging portion  140   c  of the keycap  140  respectively, and the second engaging shaft  142   a   2  of the first supporting member  142   a  and the third engaging shaft  142   b   1  of the second supporting member  142   b  are slidably engaged with the first upper engaging portion  140   b  of the keycap  140  and the second lower engaging portion  104  of the base plate  10  respectively. Such a configuration can also make the keycap  140  vertically move relative to the base plate  10  when the keyswitch  14  is pressed. 
     As shown in  FIG. 5 , a line that is connected between the center of gravity  142   a   4  of the first engaging shaft  142   a   1  and the center of gravity  142   a   5  of second engaging shaft  142   a   2  is not perpendicular to the axial direction of the first engaging shaft  142   a   1  and the axial direction of the second engaging shaft  142   a   2 , and the length of the first engaging shaft  142   a   1  is greater than the length of the second engaging shaft  142   a   2 . That is, the shapes of the upper side and the lower side (i.e., the first engaging shaft  142   a   1  and the second engaging shaft  142   a   2 ) of the first supporting member  142   a  of the scissors-like supporting structure  142  are asymmetric. Similarly, a line that is connected between the center of gravity  142   b   4  of the third engaging shaft  142   b   1  and the center of gravity  142   b   5  of fourth engaging shaft  142   b   2  is not perpendicular to the axial direction of the third engaging shaft  142   b   1  and the axial direction of the fourth engaging shaft  142   b   2 , and the length of the fourth engaging shaft  142   b   2  is larger than the length of the third engaging shaft  142   b   1 . That is, the shapes of the upper side and the lower side (i.e., the third engaging shaft  142   b   1  and the fourth engaging shaft  142   b   2 ) of the second supporting member  142   b  of the scissors-like supporting structure  142  are asymmetric. It can be clearly seen that each of the lower-left corner of the first supporting member  142   a  and the lower-left corner of the second supporting member  142   b  of the scissors-like supporting structure  142  has an inwardly recessed shape. 
       FIG. 7  is a top view of a portion of the base plate  10  and the scissors-like supporting structure  142  of the keyswitch  14  in  FIG. 1 .  FIG. 8  is another top view of the keyswitch  14  in  FIG. 1 , in which the scissors-like supporting structure  142  is indicated by dotted lines. 
     As shown in  FIG. 7 , the inwardly recessed shapes respectively located at the lower-left corners of the first supporting member  142   a  and the second supporting member  142   b  of the scissors-like supporting structure  142  are aligned with the light pervious region  140   a  of the keycap  140 . Accordingly, the first supporting member  142   a  and the second supporting member  142   b  of the scissors-like supporting structure  142  do not occupy the space above the hole  100  of the base plate  10 , so the light emitted by the light source  12  that is disposed under the base plate  10  is not obscured by the first supporting member  142   a  and the second supporting member  142   b  of the scissors-like supporting structure  142  and can be transmitted to the keycap  140 . Furthermore, the length of the third engaging shaft  142   b   1  of the second supporting member  142   b  is smaller than the length of the first engaging shaft  142   a   1  of the first supporting member  142   a , and the third engaging shaft  142   b   1  is closer to the hole  100  of the base plate  10  than the first engaging shaft  142   a   1 . That is, the length of the third engaging shaft  142   b   1  of the second supporting member  142   b  is smaller, so the third engaging shaft  142   b   1  and the hole  100  of the base plate  10  can be arranged at the same side (i.e., the lower side in  FIG. 7 ) and opposite to the first engaging shaft  142   a   1  of the first supporting member  142   a.    
     As shown in  FIG. 8 , the inwardly recessed shapes respectively located at the lower-left corners of the first supporting member  142   a  and the second supporting member  142   b  of the scissors-like supporting structure  142  are aligned with the light pervious region  140   a  of the keycap  140  (i.e., the hole  100  of the base plate  10  is aligned with the light pervious region  140   a  of the keycap  140 ). Accordingly, the first supporting member  142   a  and the second supporting member  142   b  of the scissors-like supporting structure  142  do not occupy the space under the light pervious region  140   a  of the keycap  140 , so the light emitted by the light source  12  that is disposed under the base plate  10  is not obscured by the first supporting member  142   a  and the second supporting member  142   b  of the scissors-like supporting structure  142  and can be transmitted to the keycap  140 . Furthermore, the length of the second engaging shaft  142   a   2  of the first supporting member  142   a  is smaller than the length of the fourth engaging shaft  142   b   2  of the second supporting member  142   b , and the second engaging shaft  142   a   2  is closer to the light pervious region  140   a  of the keycap  140  than the fourth engaging shaft  142   b   2 . That is, the length of the second engaging shaft  142   a   2  of the first supporting member  142   a  is smaller, so the second engaging shaft  142   a   2  and the light pervious region  140   a  of the keycap  140  can be arranged at the same side (i.e., the lower side in  FIG. 8 ) and opposite to the fourth engaging shaft  142   b   2  of the second supporting member  142   b.    
     Because the keyswitch  14  of the disclosure adopts the asymmetric scissors-like supporting structure  142  to provide support under the keycap  140 , the stability of vertical movement of the keycap  140  relative to the base plate  10  may be adversely affected. In order to solve the problem of insufficient stability during vertical movement of the keycap  140  relative to the base plate  10 , in an embodiment of the disclosure, a thickness of the keycap  140  of the keyswitch  14  is larger than 1 mm. In another embodiment of the disclosure, a thickness of the scissors-like supporting structure  142  of the keyswitch  14  is larger than 1.3 mm. However, the disclosure is not limited in this regard, and these dimensions can be adjusted according to practical requirements. 
     As shown in  FIG. 3  and  FIG. 4 , the keyswitch  14  further includes a linkage member  144 . The base plate  10  of the keyboard  1  further includes a third lower engaging portion  106 , and the bottom of the keycap  140  further includes a third upper engaging portion  140   d . The third upper engaging portion  140   d  of the keycap  140  is located at an edge of the bottom of the keycap  140 . The linkage member  144  of the keyswitch  14  is engaged with the third lower engaging portion  106  of the base plate  10  and the third upper engaging portion  140   d  of the keycap  140 , and assists to support the keycap  140  when the keycap  140  vertically moves relative to the base plate  10 , so that the stability of vertical movement of the keycap  140  relative to the base plate  10  can be improved. 
       FIG. 9  is another top view of the keyswitch  14  in  FIG. 1 . 
     As shown in  FIG. 9 , the keycap  140  of the keyswitch  14  can be made of a transparent material. The keycap  140  of the keyswitch  14  includes a laser inside-engraving layer  140   e  (e.g., the pattern “caps lock” in  FIG. 9 ), and the laser inside-engraving layer  140   e  is substantially located at the light pervious region  140   a  that is aligned with the hole  100  of the base plate  10 . Because the scissors-like supporting structure  142  does not occupy the space that is above the hole  100  of the base plate  10  and under the light pervious region  140   a  of the keycap  140 , the light emitted by the light source  12  that is disposed under the base plate  10  is not obscured by the scissors-like supporting structure  142  and can be transmitted to the pattern of the laser inside-engraving layer  140   e  of the keycap  140 . Therefore, the display result of the pattern is visually appealing and easily recognized by users. 
     In an embodiment of the disclosure, the pattern included in the laser inside-engraving layer  140   e  of the keycap  140  can be a number, a symbol, a word, or a figure, but the disclosure is not limited in this regard. 
     According to the foregoing recitations of the embodiments of the disclosure, it can be seen that the keyswitch of the disclosure adopts an asymmetric scissors-like supporting structure to provide support under a keycap, so that a certain portion (e.g., a corner of the keycap) is not occupied by the scissors-like supporting structure. Accordingly, the light emitted by a light source that is disposed at the bottom of the keyswitch is not obscured by the scissors-like supporting structure and can be transmitted to a pattern of a laser inside-engraving layer in a light pervious region of the keycap. Therefore, the display result of the pattern is visually appealing and easily recognized by users. Because the keyswitch adopts the asymmetric scissors-like supporting structure, the disclosure further improves the stability of the keycap during vertical movement by increasing the thickness of the keycap and the thickness of the scissors-like supporting structure, and additionally by disposing a linkage member for providing additional support to the keycap. 
     It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present disclosure without departing from the scope or spirit of the disclosure. In view of the foregoing, it is intended that the present disclosure cover modifications and variations of this disclosure provided they fall within the scope of the following claims.