Low profile keyboard switch assembly with snap action cantilever contact

Claim 2

A snap action switch swinger adapted to cooperate with a stationary switch contact comprising: a cantilever arm member extending from a conductive spring body member and said arm member having a fixed end and a free end; separating means for dividing said cantilever arm member into a support portion and a tongue portion, intermediate said fixed and free ends; means for introducing a difference in length as between said tongue portion and said support portion, said means imparting a curvature to the relatively longer portion, biasing said cantilever arm member into a first, stable, non-actuated configuration; and contact means at said free end, said cantilever arm member being operable, in response to movement in a direction opposite to the curvature of said longer portion, to reverse the curvature of said longer portion, biasing said cantilever arm member into a second, stable actuated configuration with said contact means in operational proximity to the stationary contact.

Claim 3

The snap action switch swinger of claim 1, above, wherein said separating means include a pair of slots extending from said fixed end toward said free end, the elongated portion intermediate said slots being considered said tongue portion and said means for introducing a difference in length include a crimp in said support portion thereby shortening said support portion relative to said tongue portion.

Claim 4

The snap action switch swinger of claim 1, above, wherein said contact means include a pair of opposed cantilever arm members, extending in a direction substantially orthogonal to said cantilever arm member direction of extension.

Claim 5

A snap action switch assembly including in combination: cantilever arm means extending from a conductive spring body member, said cantilever arm means having a fixed end and a free end; separating means for dividing said cantilever arm means into an elongated support portion and an elongated tongue portion, intermediate said fixed and free ends; means for introducing a difference in length as between said tongue portion and said support portion for imparting a curvature to the relatively longer portion and for biasing said cantilever arm means into a first, stable, non-actuated Configuration in a first direction; contact means at said free end of said cantilever arm means; and spacer support means below said conductive spring body member and including a tab portion extending under said longer portion to provide a bending point for said longer portion different from the bending point of said shorter portion in response to motion applied to said cantilever arm means; whereby motion of said cantilever arm means in a second direction, opposite to said first direction, causes said longer portion to engage said tab portion, forcing said longer portion to reverse its curvature into a second table actuated configuration for said arm means, reducing the magnitude of the force required to continue motion of said cantilever arm means in said second direction.

Claim 6

A snap action switch assembly including in combination: cantilever arm means extending from a conductive spring body member, said cantilever arm means having a fixed end and a free end; separating means for dividing said cantilever arm means into an elongated support portion and an elongated tongue portion, intermediate said fixed and free ends; means for introducing a difference in length as between said tongue portion and said support portion for imparting a curvature to the relatively longer portion and for biasing said cantilever arm means into a first, stable, non-actuated Configuration in a first direction; contact means at said free end of said cantilever arm means; and spacer support means below said conductive spring body member and including a tab portion extending under said longer portion to provide a bending point for said longer portion different from the bending point of said shorter portion in response to motion applied to said cantilever arm means; whereby motion of said cantilever arm means in a second direction, opposite to said first direction, causes said longer portion to engage said tab portion, forcing said longer portion to reverse its curvature into a second table actuated configuration for said arm means, reducing the magnitude of the force required to continue motion of said cantilever arm means in said second direction.

Claim 7

The snap action switch assembly of claim 4, above, including base plate means adjacent said spacer support means, said base plate means including fixed contact means operatively positioned to engage said contact means when said cantilever arm means are in the second stable actuated configuration.

Claim 8

The snap action switch assembly of claim 4, above, further including push button means adjacent said cantilever arm means for imparting motion in said second direction to said cantilever arm means, for actuating the switch assmebly and for maintaining the switch assembly in the second stable actuated configuration against the bias in said first direction, in response to continued operation of said push button means.

Claim 9

The snap action switch assembly of claim 4, above, wherein said relatively longer portion is said tongue portion and said relatively shorter portion is said support portion.

Claim 10

A snap action switch assembly including in combination: a. a conductive switch plate having a plurality of cantilever arms extending therefrom, each having a fixed end and a free end; b. means for providing each of said cantilever arms with a tongue portion and a support portion, and for introducing a difference in length as between said tongue portion and said support portion to impart a curvature to said tongue portion in a primary stable configuration; c. spacer support means adjacent said conductive switch plate including a plurality of tab portions, each underlying the tongue portion of a one of said arms, each said tab portion supplying a fulcrum to its associated tongue portion different from the corresponding support portion; and d. base plate means, adjacent said spacer support means, having a plurality of stationary contact elements each adapted to be engaged by a corresponding one of said cantilever arm free ends, whereby movement of a one of said cantilever arms in the direction of said base plate causes said tongue portion to engage said tab portion, reversing the curvature of said tongue portion into a secondary, stable configuration with said cantilever free end engaging said stationary contact element corresponding thereto, and whereby in the absence of a force holding said arm in said secondary, stable configuration, said arm returns to said primary stable configuration.

Claim 11

A snap action switch assembly including in combination: a. a conductive switch plate having a plurality of cantilever arms extending therefrom, each having a fixed end and a free end; b. means for providing each of said cantilever arms with a tongue portion and a support portion, and for introducing a difference in length as between said tongue portion and said support portion to impart a curvature to said tongue portion in a primary stable configuration; c. spacer support means adjacent said conductive switch plate including a plurality of tab portions, each underlying the tongue portion of a one of said arms, each said tab portion supplying a fulcrum to its associated tongue portion different from the corresponding support portion; and d. base plate means, adjacent said spacer support means, having a plurality of stationary contact elements each adapted to be engaged by a corresponding one of said cantilever arm free ends, whereby movement of a one of said cantilever arms in the direction of said base plate causes said tongue portion to engage said tab portion, reversing the curvature of said tongue portion into a secondary, stable configuration with said cantilever free end engaging said stationary contact element corresponding thereto, and whereby in the absence of a force holding said arm in said secondary, stable configuration, said arm returns to said primary stable configuration.

Claim 12

The snap action switch assembly of claim 8, above, further including: a plurality of keys, each adjacent a one of said cantilever arms for imparting motion to said arms, thereby placing said arms in the secondary stable configuration with said stationary contact engaged with the corresponding arm free end.

Claim 13

A keyboard assembly comprising, in combination: a. actuator means comprising a plurality of individually operable key members adapted to be depressed; b. a plurality of cantilevered, movable contact members having free ends and fixed ends, mounted adjacent said actuator means, each in operable proximity to a corresponding one of said plurality of key members, each of said movable contact members having an upward bias and a first, relatively stable configuration in a nonactuated, ''''up'''' position, and a second, relatively stable configuration in an aCtuated, ''''down'''' position; c. support means comprising a frame containing said plurality of movable contact members, and a plurality of fulcrum elements, each positioned adjacent and below the fixed end of a corresponding movable contact member; and d. a plurality of fixed contacts spaced apart from said plurality of movable contacts, each adapted to be engaged by a corresponding one of said plurality of movable contact members free ends, each of said movable contact members being operable in response to a limited depression of a corresponding key member to partially pivot against said fulcrum element against said upward bias to change from said first to said second relatively stable configuration, for electrically engaging said fixed and movable contacts, whereby engagement of said contacts is independent of further depression of said key member.

Claim 14

A keyboard assembly comprising, in combination: a. actuator means comprising a plurality of individually operable key members adapted to be depressed; b. a plurality of cantilevered, movable contact members having free ends and fixed ends, mounted adjacent said actuator means, each in operable proximity to a corresponding one of said plurality of key members, each of said movable contact members having an upward bias and a first, relatively stable configuration in a nonactuated, ''''up'''' position, and a second, relatively stable configuration in an aCtuated, ''''down'''' position; c. support means comprising a frame containing said plurality of movable contact members, and a plurality of fulcrum elements, each positioned adjacent and below the fixed end of a corresponding movable contact member; and d. a plurality of fixed contacts spaced apart from said plurality of movable contacts, each adapted to be engaged by a corresponding one of said plurality of movable contact members free ends, each of said movable contact members being operable in response to a limited depression of a corresponding key member to partially pivot against said fulcrum element against said upward bias to change from said first to said second relatively stable configuration, for electrically engaging said fixed and movable contacts, whereby engagement of said contacts is independent of further depression of said key member.

Claim 15

The keyboard assembly of claim 10, above, wherein each of said cantilevered movable contact members comprise separating means for dividing said contact member imto a support portion and a tongue portion intermediate said free ends including a pair of separate slots extending between said fixed and free ends; and means for introducing a difference in length as between said tongue portion and said support portion, imparting a curvature to the relatively longer portion, which in said first relatively stable configuration is a downward curvature and in said second relatively stable configuration is an upward curvature.

Claim 16

The keyboard assembly of claim 11, above, wherein said means for introducing a difference in length comprises a crimp in said support portion adjacent said contact member fixed end, whereby said tongue portion is the relatively longer portion, said crimp also providing said upward bias.