Keyboard switch assembly with multi-sectional key actuator

Claim 2

In a keyboard array including an insulator board supporting a circuit having at least one electrically conductive contact provided on one surface of said board, a resilient conductive layer means positioned to make contact with said contact upon application of a force thereto, and means separating said conductive layer means from said contact and having a window therethrough which said conductive layer may extend to make contact with said electrical contact, the improvement comprising an external plunger having a bore, an internal plunger slidably movable within a bore formed in an external plunger, a housing slidably supporting said external plunger, means coupling said housing to said board, first resilient biasing means biasing said external plunger away from said conductive layer means, second resilient biasing means biasing said internal plunger towards said conductive layer, said internal plunger positioned to apply a force against said conductive layer means to make electrical coNtact with said contact upon the application of a force applied to said external plunger, a key mounted on said external plunger and snap members provided on said external plunger to confine a portion of said internal plunger within said bore thereof.

Claim 3

In a keyboard array according to claim 1 in which said plunger portion positioned in said bore has tapered slots to permit easy entry into said bore.

Claim 4

In a keyboard array according to claim 2 in which vent channels are provided to facilitate movement of said internal plunger in said bore.

Claim 5

In a keyboard array according to claim 3 in which means are provided on both of said plungers for locating said second biasing means and wherein means are provided on said housing and external plunger for locating said first biasing means.

Claim 6

In a keyboard array including an insulator board supporting a circuit having at least one electrically conductive contact provided on one surface of said board, a resilient conductive layer means positioned to make contact with said contact upon application of a force thereto, and means separating said conductive layer means from said contact and having a window therethrough which said conductive layer may extend to make contact with said electrical contact, the improvement comprising an external plunger, an internal plunger slidably movable within a bore formed in an external plunger, a housing slidably supporting said external plunger, means coupling said housing to said board, first resilient biasing means biasing said external plunger away from said conductive layer means, second resilient biasing means biasing said internal plunger towards said conductive layer, said internal plunger positioned to apply a force against said conductive layer means to make electrical contact with said contact upon application of a force applied to said external plunger, a key mounted on said external plunger, and said array comprises a sandwich of said board, said circuit having said conductive contact on said board, said insulator layer having a window therethrough in alignment with at least a portion of said contact,said resilient conductive plastic layer means positioned on said insulator layer and said housing mounted with said plunger mounted on top of said conductive layer means.

Claim 7

In a keyboard array including an insulator board supporting a circuit having at least one electrically conductive contact provided on one surface of said board, a resilient conductive layer means positioned to make contact with said contact upon application of a force thereto, and means separating said conductive layer means from said contact and having a window therethrough which said conductive layer may extend to make contact with said electrical contact, the improvement comprising an external plunger, an internal plunger slidably movable within a bore formed in an external plunger, a housing slidably supporting said external plunger, means coupling said housing to said board, first resilient biasing means biasing said external plunger away from said conductive layer means, second resilient biasing means biasing said internal plunger towards said conductive layer, said internal plunger positioned to apply a force against said conductive layer means to make electrical contact with said contact upon application of a force applied to said external plunger, a key mounted on said external plunger, and said array comprises a sandwich of said board, said circuit having said conductive contact on said board, said insulator layer having a window therethrough in alignment with at least a portion of said contact,said resilient conductive plastic layer means positioned on said insulator layer and said housing mounted with said plunger mounted on top of said conductive layer means.

Claim 8

In a keyboard array according to claim 5 in which an insulator pad having a window therethrough in alignment with at least a portion of said window of said insulator layer and in which said housing has mounting portions which extend through holes formed in said pad, conductive layer, insulator layer means and board for joining said sandwich together.

Claim 9

In a keyboard array according to claim 2 in which said external plunger and said housing are provided with guide means for preventing rotation of said external plunger.

Claim 10

A key construction comprising a housing, a first plunger having at least a portion slidably movable within said housing and having a key attached thereto, a second plunger having a portion slidably movable within a portion of said first plunger, first resilient biasing means positioned between said plungers to urge them away from each other, said second plunger includes a portion having tapered slots and wherein said first plunger has resilient projections, said slots pushable over said projections to snap said second plunger into said first plunger and retain said second plunger within said first plunger for slidable movement therein.

Claim 11

A key construction comprising a housing, a first plunger having at least a portion slidably movable within said housing and having a key attached thereto, a second plunger having a portion slidably movable within a portion of said first plunger, first resilient biasing means positioned between said plungers to urge them away from each other, said second plunger includes a portion having tapered slots and wherein said first plunger has resilient projections, said slots pushable over said projections to snap said second plunger into said first plunger and retain said second plunger within said first plunger for slidable movement therein.