Keyswitch

Information

  • Patent Grant
  • 6242705
  • Patent Number
    6,242,705
  • Date Filed
    Tuesday, March 28, 2000
    24 years ago
  • Date Issued
    Tuesday, June 5, 2001
    23 years ago
Abstract
An improved keyswitch includes a stage having a mounting hole and a keycap having a plunger on a bottom thereof. The plunger is movably arranged within the mounting hole. The keyswitch is characterized in that one of the keycap and the stage is provided with at least one guiding rib, while the other of the keycap and the stage is provided with at least one dent corresponding to the guiding rib. The guiding rib is fit within the dent and the dent and guiding rib have multiple point contacts to restrict movement of the keycap with respect to the stage.
Description




FIELD OF THE INVENTION




The present invention relates to an improved keyswitch, especially to an improved keyswitch without using a scissors structure and having tactile effect like keyswitch using a scissors structure.




BACKGROUND OF THE INVENTION




The scissors structure comprising two levers is widely used in keyswitch, wherein the keycap is guided by the scissors structure to move upward and downward, and the. The rubber cone below the keycap is risen or collapsed to switch a circuit board on bottom of the keyswitch. The keyswitch using scissors structure has the advantages of excellent tactile effect and compact size. However, the manufacture cost is high.




It is an object of the present invention to provide an improved keyswitch wherein the keycap has restrict vertical movement within the stage, thus having more stability.




It is another object of the present invention to provide an improved keyswitch, which does not involve a scissors structure and has excellent tactile effect, thus providing compact and low-cost keyboard.




To achieve the above objects, in the inventive keyswitch, one of the keycap and the stage is provided with at least one guiding rib, another one of the keycap and the stage is provided with at least one dent corresponding to the guiding rib. The guiding rib is fit within the dent and the dent and guiding rib have multiple point contact to restrict vertical movement of the keycap within the stage.











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 perspective view of the present invention;





FIG. 2

is an exploded view of the present invention;





FIG. 3

is a longitudinal sectional view of the present invention;





FIG. 4

is a transverse sectional view of the present invention;





FIG. 5

depicting the pressing operation of keyswitch of the present invention;





FIG. 6

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





FIG. 7

is a transverse sectional view of another preferred embodiment of the present invention.











DETAILED DESCRIPTION OF PREFERRED EMBODIMENT





FIGS. 1 and 2

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


10


and a keycap


20


. The stage


10


is a hollow cylinder and formed on a base


11


. The stage


10


has a mounting hole


12


on center thereof and two clamping grooves


13


on two opposed sides thereof. The stage


10


has at least one dent


14


on outer lateral side thereof. In this preferred embodiment of the present invention, the stage


10


has four dents


14


on four comers thereof, each dent


14


has open top and lateral side.




The keycap


20


has a plunger


21


on bottom side thereof and movably arranged within the mounting hole


12


. The keycap


20


has two clamping poles


24


movably arranged within the clamping grooves


13


on two opposed sides of the stage


10


. The keycap


20


has at least one guiding rib


22


corresponding to the dent


14


. In this preferred embodiment of the present invention, the keycap


20


has four guiding ribs


22


of plate shape. The front end of the guiding rib


22


can be modified and the rear end of the guiding rib


22


has a reinforcing fork


23


. As shown in

FIG. 3

, the guiding rib


22


is fit within the dent


14


. The keyswitch is arranged atop the rubber cone


30


, the flexible circuit


40


and the base plate


50


.




As shown in

FIG. 5

, when the keycap


20


is pressed to lower down the plunger


21


, the pressing end


31


of the rubber cone


30


touches the flexible circuit


40


on the base plate


50


to switch on the flexible circuit


40


.




As shown in

FIG. 4

, 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


.




The present invention is characterized in that concave dent


14


and convex guiding rib


22


are provided between the stage


10


and the keycap


20


. The front end of the guiding rib


22


is such modified that the guiding rib


22


has multiple points contact with the dent


14


. Therefore, the concave dent


14


and convex guiding rib


22


can restrict vertical movement of the keycap


20


within the stage


10


.





FIGS. 6 and 7

show another preferred embodiment of the present invention, in the keyswitch, the stage


10


has at least one guiding rib


15


. In this preferred embodiment of the present invention, the stage


10


has four guiding ribs


15


on four corners thereof. The keycap


20


has at least one guiding pole


25


each having a dent


26


corresponding to the guiding rib


15


. In this preferred embodiment of the present invention, the keycap


20


has four dents


26


, each dent


26


has open top and lateral side. The present invention is characterized in that concave dent


26


and convex guiding rib


15


are provided between the stage


10


and the keycap


20


. The front end of the guiding rib


15


is such modified that the guiding rib


15


has multiple points contact with the dent


26


. Therefore, the concave dent


26


and convex guiding rib


15


can restrict vertical movement of the keycap


20


within the stage


10


.




To sum up, in the present invention, the provision of the concave dent and convex guiding rib can restrict vertical movement of the keycap within the stage. The stability of the keyswitch operation is enhanced without shaking problem. The inventive keyswitch does not involves scissors structure, the manufacturing cost is reduced while the compact advantage is preserved.




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 keyswitch comprising:a base plate; a flexible circuit overlaying said base plate; a rubber cone disposed on said flexible circuit, said rubber cone having a pressing end extending from an internal surface thereof and spaced from said flexible circuit; a hollow stage disposed on said flexible circuit, said stage having (a) a cavity into which said rubber cone is received, (b) a mounting hole formed through an upper surface thereof in open communication with said cavity and in aligned relationship with an upper end of said rubber cone, and (c) a plurality of vertically directed dents formed at corner portions of said stage, each dent having an open top end and lateral side; and, a keycap vertically displaceably disposed over said stage, said keycap having a plunger extending from a bottom surface thereof and passing through said mounting hole for contacting said upper end of said rubber cone, said keycap having a plurality of plate-shaped guiding ribs extending from said bottom surface and respectively disposed in aligned relationship with said plurality of dents, each said guiding rib extending through said open lateral side of a corresponding dent and having a front end shaped to provide a multipoint contact between said guiding rib and said corresponding dent, each said guiding rib having a rear end with a fork-shaped contour to provide reinforcement for said guiding rib.
  • 2. A keyswitch comprising:a base plate; a flexible circuit overlaying said base plate; a rubber cone disposed on said flexible circuit, said rubber cone having a pressing end extending from an internal surface thereof and spaced from said flexible circuit; a hollow stage disposed on said flexible circuit, said stage having (a) a cavity into which said rubber cone is received, (b) a mounting hole formed through an upper surface thereof in open communication with said cavity and in aligned relationship with an upper end of said rubber cone, and (c) a plurality of plate-shaped guiding ribs extending from corner portions of said stage; and, a keycap vertically displaceably disposed over said stage, said keycap having a plunger extending from a bottom surface thereof and passing through said mounting hole for contacting said upper end of said rubber cone, said keycap having a plurality of vertically directed concave dents extending from said bottom surface and respectively disposed in aligned relationship with said plurality of guiding ribs, each dent having an open end and lateral side, each said guiding rib extending through said open lateral side of a corresponding dent and having a front end shaped to provide a multipoint contact between said guiding rib and said corresponding dent.
US Referenced Citations (5)
Number Name Date Kind
4939324 English Jul 1990
5201824 Kato et al. Apr 1993
5670759 Hsu Sep 1997
5938009 Huang Aug 1999
6121564 Huang Sep 2000