Stable keyswitch

Information

  • Patent Grant
  • 6204462
  • Patent Number
    6,204,462
  • Date Filed
    Tuesday, March 28, 2000
    24 years ago
  • Date Issued
    Tuesday, March 20, 2001
    23 years ago
Abstract
An improved keyswitch comprises a stage having a mounting hole and a keycap having a plunger on bottom thereof. The plunger is movably arranged within the plunger. At least one guiding rib is provided within the stage or on lateral side of the keycap; and at least one groove corresponding to the guiding rib is provided on lateral side of the keycap or within the stage, the guiding rib fit within the groove such that the keycap is movable upward and downward within the mounting hole without shaking. The keycap is in contact with the stage on lateral side thereof, the friction therebetween is reduced.
Description




FIELD OF THE INVENTION




The present invention relates to a stable keyswitch, especially to a stable keyswitch, which will not shake during operation and has compact height.




BACKGROUND OF THE INVENTION




As shown in

FIG. 1

, a conventional keyswitch comprises a keycap


10




a


and a stage


11




a


. The stage


11




a


has a mounting hole


12




a


on center thereof. The keycap


10




a


has a plunger


13




a


on bottom thereof and movably fit within the mounting hole


12




a


. When the keycap


10




a


is pressed to lower down the plunger


13




a


, the pressing end


15




a


of the rubber cone


14




a


touches the flexible circuit


16




a


on the base plate


17




a


to switch on the flexible circuit


16




a


. When the keycap


10




a


is released, the pressing end


15




a


of the rubber cone


14




a


leaves the flexible circuit


40


due to the elasticity of the rubber cone


30


, thus switching off the flexible circuit


40


. However, the above mentioned keyswitch has relatively large height and keycap is unstable if the height of the keyswitch is reduced without careful design.




It is an object of the present invention to provide a stable keyswitch wherein the keycap has restrict vertical movement within the stage, thus having more stability. The friction between the keycap and the stage is reduced.




To achieve the above objects, in the inventive keyswitch, at least one guiding rib is provided within the stage or on lateral side of the keycap; and at least one groove corresponding to the guiding rib is provided on lateral side of the keycap or within the stage, the guiding rib fit within the groove such that the keycap is movable upward and downward within the mounting hole without shaking. The keycap is in contact with the stage on lateral side thereof, the friction therebetween is reduced.




The various objects and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawing, in which:











BRIEF DESCRIPTION OF DRAWING





FIG. 1

is a sectional view of prior art keyswitch;





FIG. 2

is a longitudinal sectional view of the present invention;





FIG. 3

is a transverse sectional view of the present invention;





FIG. 4

is an exploded view of the present invention;





FIG. 5

is a perspective view of the present invention;





FIG. 6

is a longitudinal sectional view of another preferred embodiment of the present invention;





FIG. 7

is an exploded view of another preferred embodiment of the present invention;





FIG. 8

is a perspective view of another preferred embodiment of the present invention.











DETAIL DESCRIPTION OF PREFERRED EMBODIMENT





FIGS. 4 and 5

show a preferred embodiment of the present invention, the keyswitch comprises a stage


10


and a keycap


20


. The stage


10


is a hollow tube and formed on a base


11


. The stage


10


has a mounting hole


12


on center thereof and two mute bevels


13


on two inner sides of the mounting hole


12


as shown in FIG.


4


. Moreover, the mounting hole


12


has at least one guiding groove


14


on inner sidewall thereof. In this embodiment, the mounting hole


12


has eight guiding grooves


14


on four inner sidewalls thereof.




As shown in

FIG. 2

, the keycap


20


is of hollow-hat shape and has a plunger


24


. The keycap


20


has extrusive skirt


21


on bottom side thereof and two elastic hooks


22


formed on outer side of the extrusive skirt


21


. The extrusive skirt


21


has at least one guiding rib


23


on outer side thereof In this embodiment, the extrusive skirt


21


has eight guiding ribs


23


on four outer sidewalls thereof.




As shown in

FIG. 2

, the keycap


20


is assembled into the mounting hole


12


from the bottom thereof direction and the keycap


20


is movable upward and downward within the mounting hole


12


. The extrusive skirt


21


is blocked by a flange


25


on the top end of the mounting hole


12


to confine the motion of the keycap


20


and prevent the ejection of the keycap


20


. The two elastic hooks


22


contact the two mute bevels


13


on two inner sides of the mounting hole


12


to reduce striking noise between the keycap


20


and the stage


10


. As shown in

FIG. 3

, the guiding ribs


23


is fit into corresponding guiding groove


14


. The thus-assembled keyswitch is arranged on the rubber cone


30


, the flexible circuit


40


and base plate


50


of the keyboard.




When the keycap


20


is pressed to lower down the plunger


24


, the plunger


24


touches the rubber cone


30


. The pressing end


31


of the rubber cone


30


switch on the flexible circuit


40


on the base plate


50


. When the keycap


20


is released, the pressing end


31


of the rubber cone


30


leaves the flexible circuit


40


due to the elasticity of the rubber cone


30


, thus switching off the flexible circuit


40


.





FIGS. 7 and 8

show another preferred embodiment of the present invention, in the keyswitch, the mounting hole


12


has an inner stage


15


of hollow cylinder shape therein, The two mute bevels


13


are placed on two opposed inner sides of the inner stage


15


, as shown in FIG.


6


. The guiding grooves


14


are arranged on the outer side of the inner stage


15


, the two elastic hooks


22


are arranged on the inner side of the keycap


20


. The keycap


20


is assembled into the mounting hole


12


from top direction and the keycap


20


is movable upward and downward within the mounting hole


12


. The two elastic hooks


22


contact the two mute bevels


13


on two inner sides of the mounting hole


12


. The guiding ribs


23


are fit into corresponding guiding grooves


14


.




Moreover, the position of the guiding ribs


23


and the guiding grooves


14


can be interchanged. That is, the guiding ribs


23


are arranged on the stage


10


and the guiding grooves


14


are arranged on the keycap


20


.




The present invention is characterized in that concave groove


14


and convex guiding rib


23


are provided between the stage


10


and the keycap


20


. The concave groove


14


and convex guiding rib


22


can restrict vertical movement of the keycap


20


within the stage


10


. The keycap


20


is in contact to the stage


10


by the lateral side thereof, the friction is reduced. Moreover, the height of the keyboard is reduced while the key stroke is unchanged.




To sum up, in the present invention, the provision of the concave groove and convex guiding rib can restrict vertical movement of the keycap within the stage. The stability of the keyswitch operation is enhanced and the height of the keyswitch is reduced without shaking problem.




Although the present invention has been described with reference to the preferred embodiment thereof, it will be understood that the invention is not limited to the details thereof. Various substitutions and modifications have suggested in the foregoing description, and other will occur to those of ordinary skill in the art. Therefore, all such substitutions and modifications are intended to be embraced within the scope of the invention as defined in the appended claims.



Claims
  • 1. A stable keyswitch comprising:a stage having a mounting hole and a base surrounding the mounting hole, the base having a flange portion overlaying a portion of said mounting hole; and, a keycap having a plunger extending from a bottom thereof, the keycap being movably arranged within the stage for displacing the plunger, the keycap including a circumferential outwardly extended skirt formed on a lower end thereof, one of the stage within the mounting hole or on a lateral side of the skirt of the keycap being formed with at least one guiding rib thereon, and an opposite one of lateral side of the skirt of the keycap or the stage within mounting hole having at least one groove formed therein corresponding to the at least one guiding rib, the at least one guiding rib being disposed within the at least one groove such that the keycap is movable upward and downward within the mounting hole without shaking, upward movement of the keycap being limited by the skirt contacting the flange portion of the base.
  • 2. The stable keyswitch as recited in claim 1, wherein the keycap is assembled to the stage from beneath the stage.
  • 3. The stable keyswitch as recited in claim 1, wherein the skirt of the keycap and the mounting hole of the stage each includes four sidewalls, each of the four sidewalls of the skirt having a pair of guiding ribs formed thereon and each of the four sidewalls of the mounting hole having a corresponding pair of grooves formed therein for respective receipt of the pair of guiding ribs therein.
  • 4. The stable keyswitch as recited in claim 1, wherein the skirt of the keycap and the mounting hole of the stage each includes four sidewalls, each of the four sidewalls of the mounting hole having a pair of guiding ribs formed thereon and each of the four sidewalls of the skirt having a corresponding pair of grooves formed therein for respective receipt of the pair of guiding ribs therein.
US Referenced Citations (7)
Number Name Date Kind
4556769 Inaba Dec 1985
5406277 Lee Apr 1995
5496982 Tsai Mar 1996
5710397 Liao Jan 1998
5907612 Aggus et al. May 1999
5938009 Huang Aug 1999
6056456 Kinoshita May 2000