Abstract:
A keyboard includes a main board and at least one key structure positioned on the main board. The key structure includes a key switch and a key cap. The key cap is combined with the key switch. The key switch includes a key base and a shaft movably positioned on the key base. The keycap includes a main body and a cushion member. The main body is positioned on the shaft of the key switch. The main body is spaced apart from the contact surface of the key base. The main body is moved forward and backward relative to the key base with movement of the shaft. The cushion member is positioned at one side of the main body facing the contact surface. While the main body is moved to the contact surface, the cushion member abuts on the contact surface, so as to avoid the main body from hitting the key base directly, and hence minimizing the noise that is produced by the moving parts.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    This disclosure relates to a key cap, key structure and a keyboard and, more particularly, to a key cap, a key structure with key in mechanistic model, and a keyboard with the key structures. 
         [0003]    2. Related Art 
         [0004]    Keyboards have become the dominant peripheral device for inputting words, symbols and numbers. In addition to computers, consumer electronics or large factory machines are also equipped with key structures that allow for input in order to operate these machines. 
         [0005]    Overtime keyboards have evolved in their designs and functions. For example, there are foldable keyboards, thin film keyboards, waterproof keyboards and keyboards with backlight. More common keyboards are divided into two types: mechanistic model and the thin film model. 
         [0006]    The structure of keys in mechanistic model includes (1) key cap, (2) key base, and (3) a shaft. The structure also includes other equipment located inside the key base such as the spring. When user presses the key cap to have it move downwardly, the key cap drives the shaft down producing the signal which the key represents. However, when the user presses the key, the spring of the cap and the downward movement of the key cap produce a noise as it crashes into the key base. 
         [0007]    Due to this movement, the key base and the key cap sustain damage and may become inoperable overtime. Furthermore, the process also generates an unpleasant noise. The noise interferes with the work of users and may also affect others in the vicinity. Hence, it is not convenient to use this type of keyboard in a quiet environment such as an office or a library. Therefore, manufactures try to discover alternative methods in minimizing the noise of keyboards. 
       SUMMARY OF THE INVENTION 
       [0008]    In view of the limitations described above, this disclosure provides a key cap, a key structure and a keyboard with the key structure in order to solve the limitations of conventional keyboards that generate noise, limiting the uses of the keyboard to particular environments and creating inconvenience for users. 
         [0009]    The key cap is adapted for coupling with a key switch. The key switch includes a key base and a shaft. The shaft is movably positioned on the key base. The key cap includes a main body and a cushion member. The main body is positioned on the shaft and is spaced apart from a contact surface of the key base. The main body is moved forward and backward relative to the key base with movement of the shaft. The cushion member is positioned on one side of the main body facing the contact surface. When the main body moves to the contact surface, the cushion member abuts on the contact surface, and maintains resistance against the contact surface. 
         [0010]    The key structure includes a key switch and a key cap. The key switch includes a key base, a resilient member, and a shaft. The key base includes a contact surface. The resilient member and the shaft are located in the key base. The shaft is placed on the resilient member, and is moved forward and backwards between an operating position and a releasing position relative to the key base. The shaft stays at the releasing position, and presses the resilient member while at the operating position. The key cap is located on the shaft, and is spaced apart from the contact surface of the key base. The key cap includes a cushion member. The cushion member is located on one side of the key cap facing the contact surface. While the shaft is located at the operating position, the cushion member abuts on the contact surface, and maintains resistance against the contact surface. 
         [0011]    The keyboard includes a main board, and a plurality of key structures. The main board includes a plurality of cavities. The key structures are located in the said cavities. Each of the key structures includes a key switch, and a key cap. The key switch includes a key base, a resilient member, and a shaft. The key base includes a contact surface. The resilient member is positioned in the key base. The shaft is positioned on the resilient member and is able to be moved forward and back between an operating position and a releasing position relative to the key base. The shaft stays at the releasing position, and presses the resilient member while at the operating position. The key cap is placed on the shaft, and is spaced apart with the contact surface of the key base. The key cap includes a cushion member. The cushion member is positioned at one side of the key cap facing the contact surface. When the shaft is located at the operating position, the cushion member abuts on the contact surface and maintains resilience against the contact surface. Accordingly, a key cap with a cushion member is disclosed for preventing punching or crashing from the key cap and the key base, so as to absorb the force because of the material characters of the cushion member. In this way, the noise of the keyboard can be minimized, and the comfort of use can be increased, allowing the uses of these keyboards in various environments. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    The present invention will become more fully understood from the following detailed description of some illustrative embodiments in conjunction with the accompanying drawings, in which: 
           [0013]      FIG. 1  is a diagram view of a keyboard in assembling situation in accordance with a first embodiment; 
           [0014]      FIG. 2  is an exploded diagram view of a key structure in accordance with the first embodiment; 
           [0015]      FIG. 3  is a diagram view of the key structure in assembling situation in accordance with the first embodiment; 
           [0016]      FIG. 4  is a diagram view of the key structure in operation in accordance with the first embodiment; 
           [0017]      FIG. 5  is a diagram view of a key structure in assembling situation in accordance with a second embodiment; 
           [0018]      FIG. 6  is a diagram view of the key structure in operation in accordance with the second embodiment. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0019]    The following two embodiments disclose a key cap  220 , a key structure  200  and a keyboard  10  in mechanistic model in accordance with the present invention. 
         [0020]    Please refer to  FIGS. 1 to 3 ;  FIG. 1  is a diagram view of a keyboard in assembling situation in accordance with the first embodiment.  FIG. 2  is an exploded diagram view of a key structure in accordance with the first embodiment. 
         [0021]    The keyboard  10  is in accordance with the first embodiment and includes a main board  100  and a plurality of key structures  200 . The main board  100  includes a plurality of cavities  110 . Each of the key structures  200  couples to each of the cavities  110  so as to detachably engage with the main board  100 . Each of the key structures  200  includes a key switch  210  and a key cap  220 . The key cap  220  is detachably engaged on the key switch  210 . 
         [0022]    More specifically, the key switch  210  of the first embodiment includes a key base  211 , a resilient member  212  and a shaft  213 . The key base  211  includes a contact surface  2111  and a space. The space is defined inside the key base  211 . An opening of the space is formed at the contact surface  2111 . The resilient member  212  and the shaft  213  couple to the space of the key base  211  through the opening respectively. 
         [0023]    The shaft  213  is positioned onto the resilient member  212 , or in non-pressing situation stays at a releasing position P 1  relative to the key base  211 . The shaft  213  is able to press the resilient member  212  so as to move to the operating position P 2  relative to the key base  211  (as shown in  FIG. 4 ). Furthermore, the shaft  213  includes a protruding member  2131 . The protruding member  2131  is defined at one side of the shaft  213  opposite to the resilient member  212 . The shape of the protruding member  2131  can be designed, but should not be limited to a cylindrical or a polygon shape. The protruding member  2131  is exposed out through the opening and protrudes out of the contact surface for coupling with the key cap  220 . It is notable that the shaft  213  may be moved forward and back relative to the key base  211  via the elastic force generated from the resilient member  212 . The resilient member  212  in the first embodiment is a compression spring, but it should not be limited to the first embodiment. 
         [0024]    The key cap  220  includes a main body  221  and a cushion member  222 . The main body  221  is made of thermoplastic materials such as polybutylece terephthalate (PBT) or polyformaldehyde (POM). Using thermoplastic materials allows for easy shaping. Furthermore, the material has good crashworthiness and wear-resisting ability. 
         [0025]    A top surface and a bottom surface opposite to the top surface are defined in the main body  221 . A coupling slot  223  and a trench  224  are formed at the bottom surface of the main body  221 . More specifically, the coupling slot  223  is formed at an inner portion of a protruding part extended from the bottom surface, and the trench  224  is formed surround the outer portion of the protruding part extended from the bottom surface. In this way, a concave structure is formed at the bottom surface. The coupling slot  223  in the first embodiment is a blind hole, but it should not be limited to the first embodiment. The shape of the coupling slot  223  matches with the shape of the protruding member  2131 . The cushion member  222  is engaged within the trench  224 . The shape of the cushion member  222  matches with the shape of the trench  224 . The cushion member  222  can be made out of any materials with resilience, and which can absorb the force and the noise from crashing such as foam, silicon rubber pad, rubber pad; so as to provide the main body  221  a cushioning function. 
         [0026]    In addition, the engagement way of the cushion member  222  and the trench  224  can be done by agglutination or by embedment but it should not be limited to these methods alone. 
         [0027]    Please further refer to  FIGS. 2 to 4 .  FIG. 4  is a diagram view of the key structure in operation in accordance with the first embodiment. In greater detail, the coupling slot  223  in the main body  221  of the key cap  220  couples onto the protruding member  2131  of the shaft  213 , tightly engaging with each other. The cushion member  222  in the trench  224  of the main body faces the contact surface  2111  of the key base  211 . Therefore, when the shaft  213  stays at the releasing position P 1 , the main body  221  and the contact surface  2111  of the key base is spaced apart from each other with a distance. On the other hand, when the shaft  213  is pressed downwardly with an extra force and is moved to an operating position P 2 , the cushion member  222  abuts on the contact surface  2111 , and maintains resistance against the contact surface  2111  so as to absorb the force from the key cap and then provide a cushion function. As a result, the key cap  220  can prevent crashing the key base  211  directly so as to avoid clicking noise or damages. Besides, when the shaft  213  is pressed with additional force and is moved to the operating position P 2 , and thus compresses the resilient member  212 . The resilient member  212  generates an elastic force. When the extra force disappears, the shaft  213  is moved back to the releasing position P 1  with the elastic force. 
         [0028]    Accordingly, users can type in words by repeating the clicking action described previously. The noise produced by typing can be minimized, because the cushion member  222  provides the cushion function so as to prevent the main body  221  of the key cap  220  from crashing into the key base  211  directly. 
         [0029]    Please refer to  FIGS. 5 and 6 .  FIG. 5  is a diagram view of a key structure in assembling situation in accordance with a second embodiment.  FIG. 6  is a diagram view of the key structure in operation in accordance with the second embodiment. The key cap  220 , the key structure  200  and the keyboard disclosed in the second embodiment are similar with those disclosed in the first embodiment. The following description will focus on the differences. 
         [0030]    The key cap  220 , in accordance with the second embodiment, includes a main body  221  and a cushion member  222 . The main body  221  is made of thermoplastic materials such as polybutylece terephthalate (PBT) or polyformaldehyde (POM). Thermoplastic materials are easy to shape and have good crashworthiness and wear-resisting properties. 
         [0031]    A top surface and a bottom surface opposite to the top surface are also defined in the main body  221 . A coupling slot  223  and a trench  224  are formed at the bottom surface of the main body  221 . More specifically, the coupling slot  223  is a blind hole formed at an inner portion of a protruding part extended from the bottom surface. The shape of the coupling slot  223  matches with the shape of the protruding member  2131  of the shaft  213 . The trench  224  is a concave structure formed around the outer portion of the protruding part extended from the bottom surface. 
         [0032]    The difference between the second embodiment and the first embodiment is that the cushion member  222  of the key cap  220  is a spring in the second embodiment. One end of the cushion member  222  is engaged within the trench  224  of the main body  221 . The cushion member  222  is slipped onto the outer surface of the protruding part. In other words, the cushion member  222  surrounds the coupling slot  223 . The other end of cushion member  222  can be against the contact surface  2111  of the key base  211 , but should not be limited. In this way, the cushion member  222 , a spring, is able to provide cushion function via the elastic force of the spring. In addition, the disposition of the cushion member  222  can be designed in other ways. For example, one end of the cushion member  222  can be fixed on the main body  221 ; the other end of the cushion member  222  can be dangled above the contact surface  2111  of the key base. In this way, the cushion function can also be provided during the process that the main body  221  of the key cap  220  is moved backward and forward relative to the key base  211 . 
         [0033]    When the shaft  213  stays at a releasing position P 1  as usual, or during non-pressing situation, the main body  221  and the contact surface  2111  of the key base  211  are spaced apart with a distance from each other. On the other hand, when the key cap  220  is pressed downwardly with additional force, the main body  221  is moved to the contact surface  2111  and presses the shaft  213  downwardly to an operating position P 2  so as to compress the cushion member  222  to abut on the contact surface  2111 . In this way, when the main body  221  of the key cap  220  is moved to the key base, a cushion function can be provided by the cushion member  222 . Therefore, the noise from the main body  221  of the key cap  220  crashing the key base  211  directly can be prevented. Additionally, when the resilient member  212  of the key switch  210  is compressed by the shaft  213 , the resilient member  212  generates an elastic force. When the extra force disappears, the shaft  213  is moved back to the releasing position P 1  with the elastic force, and also the motion of the shaft  213  drives the main body  221  of the key cap  220  to be moved away from the contact surface  2111  of the key base  211 . 
         [0034]    Accordingly, users can use the keyboard by repeating the clicking action described previously. The noise produced during typing can be avoided, because the cushion member  222  provides the cushion function so as to prevent the main body  221  of the key cap  220  from crashing the key base  211  directly. 
         [0035]    Therefore, the keyboard with keycaps having cushion member prevents the key cap and the key base from crashing while operating. In addition, the cushion member is able to absorb the crashing force because of the materials which the cushion member made from. Hence, the noise produced by pressing the keys can be significantly decreased and improve comfort of users as to meet the users&#39; needs. 
         [0036]    The foregoing description of the exemplary embodiments of the disclosure has been presented only for the purposes of illustration and description and is not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Many modifications and variations are possible in light of the disclosure above. The embodiments were chosen and described in order to explain the principles of the disclosure and their practical application so as to enable others of ordinary skill in the art to utilize the disclosure and various embodiments and with various modifications as are suited to the particular use contemplated. Alternative embodiments will become apparent to those of ordinary skills in the art to which the present disclosure pertains without departing from its spirit and scope. Accordingly, the scope of the present disclosure is defined by the appended claims rather than the foregoing description and the exemplary embodiments described therein.