Abstract:
A keyswitch includes a key cap, a base, a circuit board, a film, a resilient member and a pressure sensing member. The circuit board is disposed on the base. The film is disposed on the circuit board. The resilient member is disposed between the film and the key cap. The pressure sensing member is disposed at a position selected from a group consisting of a position between the resilient member and the film, a position between the film and the circuit board, and a position between the circuit board and the base. When the key cap is pressed by an external force, the pressure sensing member senses a magnitude of the external force.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The invention relates to a keyswitch and a keyboard and, more particularly, to a keyswitch capable of sensing a magnitude of a pressing force. 
         [0003]    2. Description of the Prior Art 
         [0004]    A keyboard, which is the most common input device, can be found in variety of electronic equipments for users to input characters, symbols, numerals and so on. From consumer electronic products to industrial machine tools are all equipped with a keyboard for purpose of operation. 
         [0005]    In general, the conventional keyboard is only used for purpose of input and cannot sense a pressing force generated by a user. Therefore, for example, when the user presses the keyswitch with a large force due to angry, the convention keyboard cannot sense the force generated by the user and then cannot inform the user to relax through a predetermined program installed in a computer. Furthermore, when the user presses the keyswitch with a slight force due to low spirit, the convention keyboard cannot sense the force generated by the user and then cannot inform the user to brace up through the predetermined program installed in the computer either. 
       SUMMARY OF THE INVENTION 
       [0006]    Therefore, an objective of the invention is to provide a keyswitch capable of sensing a magnitude of a pressing force. 
         [0007]    According to an embodiment, a keyswitch of the invention comprises a key cap, a base, a circuit board, a film, a resilient member and a pressure sensing member. The circuit board is disposed on the base. The film is disposed on the circuit board. The resilient member is disposed between the film and the key cap. The pressure sensing member is disposed at a position selected from a group consisting of a position between the resilient member and the film, a position between the film and the circuit board, and a position between the circuit board and the base. When the key cap is pressed by an external force, the pressure sensing member senses a magnitude of the external force. 
         [0008]    According to another embodiment, a keyswitch of the invention comprises a key cap, a base, a pressure sensing circuit board and a resilient member. The pressure sensing circuit board is disposed on the base. The resilient member is disposed between the pressure sensing circuit board and the key cap. When the key cap is pressed by an external force, the pressure sensing circuit board senses a magnitude of the external force. 
         [0009]    According to another embodiment, a keyswitch of the invention comprises a key cap, a base, a circuit board, a pressure sensing member and a resilient member. The circuit board is disposed on the base. The pressure sensing member is disposed on the circuit board. The resilient member is disposed between the pressure sensing member and the key cap. When the key cap is pressed by an external force, the pressure sensing member senses a magnitude of the external force. 
         [0010]    Another objective of the invention is to provide a keyboard, which comprises a base and a plurality of keyswitches disposed on the base. The structure of one of the keyswitches of the keyboard is mentioned in the above. 
         [0011]    As mentioned in the above, the invention adds the pressure sensing member into the keyswitch or integrates the pressure sensing member with other components (e.g. circuit board or film), so as to enable the keyswitch to sense a magnitude of a pressing force generated by a user. 
         [0012]    These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  is a schematic diagram illustrating a keyboard according to a first embodiment of the invention. 
           [0014]      FIG. 2  is a cross-sectional view illustrating a keyswitch along line X-X shown in  FIG. 1 . 
           [0015]      FIG. 3  is a cross-sectional view illustrating a keyswitch according to a second embodiment of the invention. 
           [0016]      FIG. 4  is a cross-sectional view illustrating a keyswitch according to a third embodiment of the invention. 
           [0017]      FIG. 5  is a cross-sectional view illustrating a keyswitch according to a fourth embodiment of the invention. 
           [0018]      FIG. 6  is a cross-sectional view illustrating a keyswitch according to a fifth embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0019]    Referring to  FIG. 1 ,  FIG. 1  is a schematic diagram illustrating a keyboard  1  according to a first embodiment of the invention. As shown in  FIG. 1 , the keyboard  1  comprises a base  3  and a plurality of keyswitches  5 . The keyswitches  5  are disposed on the base  3  for a user to press, so as to execute desired function correspondingly. 
         [0020]    Referring to  FIG. 2 ,  FIG. 2  is a cross-sectional view illustrating a keyswitch  5  along line X-X shown in  FIG. 1 . As shown in  FIG. 2 , the keyswitch  5  comprises a key cap  50 , a base  3 , a circuit board  52 , a film  54 , a resilient member  56 , a lift support device  58  and a pressure sensing member  59 . The circuit board  52  is disposed on the base  3 , the film  54  is disposed on the circuit board  52 , and the resilient member  56  is disposed between the film  54  and the key cap  50 . In practical applications, the circuit board  52  has a switch  520 , such as a membrane switch or other types of switches. The film  54  may be a mylar film or be made of other plastic materials for isolation. The resilient member  56  has a trigger portion  560 . The resilient member  56  may be, but not limited to, a rubber dome. The resilient member  56  is used to provide elastic force while the key cap  50  moves upward and downward with respect to the case  3 . When the keyswitch  5  is pressed, the trigger portion  560  of the resilient member  56  triggers the switch  520  of the circuit board  52 , so as to execute desired function correspondingly. 
         [0021]    As shown in  FIG. 2 , the lift support device  58  is disposed between the key cap  50  and the base  3 . The key cap  50  has a first sliding groove  500  and a first engaging groove  502 . The base  3  has a second sliding groove  30  and a second engaging groove  32 . The lift support device  58  comprises a first support member  580  and a second support member  582 , wherein the second support member  582  is pivotally connected to the first support member  580 . The first support member  580  has a first sliding portion  5800  and a first pivoting portion  5802 , wherein the first sliding portion  5800  is slidably disposed in the first sliding groove  500  and the first pivoting portion  5802  is pivotally disposed in the second engaging groove  32 . The second support member  582  has a second sliding portion  5820  and a second pivoting portion  5822 , wherein the second sliding portion  5820  is slidably disposed in the second sliding groove  30  and the second pivoting portion  5822  is pivotally disposed in the first engaging groove  502 . Accordingly, when the keyswitch  5  is pressed, the key cap  50  will move toward the base  3  along with the lift support device  58 . 
         [0022]    In this embodiment, the pressure sensing member  59  may be, but not limited to, a strain gage. The pressure sensing member  59  is used to sense the magnitude of a pressing force. As shown in  FIG. 2 , the pressure sensing member  59  can be disposed between the resilient member  56  and the film  54 . When the key cap  50  is pressed by an external force, the resilient member  56  is pressed by the external force at the same time, so that the pressure sensing member  59  senses the magnitude of the external force via the resilient member  56 . Accordingly, the keyboard  1  of the invention can sense the magnitude of the external force, which is acted on the keyswitch  5  by a user, by the pressure sensing member  59 . 
         [0023]    Referring to  FIG. 3 ,  FIG. 3  is a cross-sectional view illustrating a keyswitch  5 ′ according to a second embodiment of the invention. As shown in  FIGS. 2 and 3 , the main difference between the first and second embodiments is that the pressure sensing member  59  is disposed between the film  54  and the circuit board  52 . It should be noted that the principles and structures of the components with identical labels in  FIGS. 3 and 2  are substantially the same, so they will not be depicted herein again. 
         [0024]    Referring to  FIG. 4 ,  FIG. 4  is a cross-sectional view illustrating a keyswitch  5 ″ according to a third embodiment of the invention. As shown in  FIGS. 2 and 4 , the main difference between the first and third embodiments is that the pressure sensing member  59  is disposed between the circuit board  52  and the base  3 . It should be noted that the principles and structures of the components with identical labels in  FIGS. 4 and 2  are substantially the same, so they will not be depicted herein again. 
         [0025]    Referring to  FIG. 5 ,  FIG. 5  is a cross-sectional view illustrating a keyswitch  7  according to a fourth embodiment of the invention. As shown in  FIG. 5 , the keyswitch  7  comprises a key cap  50 , a base  3 , a resilient member  56 , a lift support device  58  and a pressure sensing circuit board  70 . The pressure sensing circuit board  70  is disposed on the base  3 . The resilient member  56  is disposed between the pressure sensing circuit board  70  and the key cap  50 . Furthermore, a film (not shown) may be selectively disposed on the pressure sensing circuit board  70  of the keyswitch  7  and the film may be a mylar film or be made of other plastic materials for isolation. The main difference between the first and fourth embodiments is that the pressure sensing circuit board  70  consists of a strain gage and a circuit board. The pressure sensing circuit board  70  is capable of sensing the magnitude of a pressing force and provides a switch relative to the keyswitch  7 . For example, when the key cap  50  is pressed by an external force, the resilient member  56  is pressed by the external force at the same time, so that the pressure sensing circuit board  70  senses the magnitude of the external force via the resilient member  56 . Accordingly, the invention can sense the magnitude of the external force, which is acted on the keyswitch  7  by a user, by the pressure sensing circuit board  70 . It should be noted that the principles and structures of the components with identical labels in  FIGS. 5 and 2  are substantially the same, so they will not be depicted herein again. 
         [0026]    Referring to  FIG. 6 ,  FIG. 6  is a cross-sectional view illustrating a keyswitch  9  according to a fifth embodiment of the invention. As shown in  FIG. 6 , the keyswitch  9  comprises a key cap  50 , a base  3 , a circuit board  52 , a resilient member  56 , a lift support device  58  and a pressure sensing member  59 . The circuit board  52  is disposed on the base  3 . The pressure sensing member  59  is disposed on the circuit board  52 . The main difference between the first and fifth embodiments is that the keyswitch  9  does not comprise a film. In this embodiment, the pressure sensing member  59  may be a strain gage covered by an isolated material, such that the pressure sensing member  59  is capable of sensing the magnitude of a pressing force and can be used for isolation. For example, when the key cap  50  is pressed by an external force, the resilient member  56  is pressed by the external force at the same time, so that the pressure sensing member  59  senses the magnitude of the external force via the resilient member  56 . Accordingly, the invention can sense the magnitude of the external force, which is acted on the keyswitch  9  by a user, by the pressure sensing member  59 . It should be noted that the principles and structures of the components with identical labels in  FIGS. 6 and 2  are substantially the same, so they will not be depicted herein again. 
         [0027]    As mentioned in the above, the invention adds the pressure sensing member into the keyswitch or integrates the pressure sensing member with other components (e.g. circuit board or film), so as to enable the keyswitch to sense a magnitude of a pressing force generated by a user. For example, after sensing the magnitude of the pressing force generated by the user, a computer may obtain an emotion status of the user and then informs the user of a specific response through a predetermined program installed in the computer. When the user presses the keyswitch with a large force due to angry, the keyboard of the invention may inform the user to relax. Furthermore, when the user presses the keyswitch with a slight force due to low spirit, the keyboard of the invention may inform the user to brace up. It should be noted that the practical applications of the invention are not limited to the aforesaid embodiments. 
         [0028]    Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention.