Thin keyboard having torsion bar keyswitch hinge members

A method for producing a keyswitch assembly from a thin sheet of resilient material having a first resiliency, the method comprising the steps of:

• cutting out a keyswitch keyface hinge member from the sheet of material, the keyface hinge member having a base section and an intermediate section which interface at a first living hinge along the first axis, the hinge member further including a keyface section which interfaces with the intermediate section at a second living hinge along the second axis, the base section including a side still connected to a remainder of the sheet, the key face section being farthest from the connection to the remainder of the sheet, wherein the base section defines a first plane and the keyface section defines a second plane substantially parallel to said first plane when said hinge member is in a quiescent condition, said intermediate section defining a third plane traverse to said first plane and said second plane when the keyface hinge member is in said quiescent condition;
• and
• increasing the resiliency of the first and second living hinges to a second resiliency greater than the first resiliency.

A keyswitch assembly comprising:

• electrical contact members having normally separated contacts, which make electrical contact when the keyswitch assembly is vertically compressed;
• a resilient material having a cutout hinge member, the hinge member supporting a key face affixed thereon and pivotable about first and second horizontal axes intersecting the hinge member, the hinge member having a first resiliency, the hinge member including a base section and an intermediate section which interface at a first living hinge along the first axis, the hinge member further including a key section which interfaces with the intermediate section at a second living hinge along the second axis, the first and second living hinges having a second resiliency which is greater than the first resiliency, wherein the first and second living hinges have a chemical makeup, as a result of at least one (i) optical treatment, (ii) chemical treatment, and (iii) thermal treatment, which results in the second resiliency;
• whereby, when the key face is pressed, the hinge member pivots about the first and second axes to make the electrical contact between the electrical contact members, and the intermediate section acts as a torsion bar to restrain the key face from twisting when pressed.

A method for producing a keyswitch assembly from a resilient material having a first resiliency, the method comprising:

• forming a keyswitch keyface hinge member from the material, the keyface hinge member having a base section and an intermediate section which interface at a first living hinge along the first axis, the hinge member further including a keyface section which interfaces with the intermediate section at a second living hinge along the second axis, the base section including a side connected to a remainder of the sheet, the key face section being farthest from the connection to the remainder of the sheet;
• and
• increasing the resiliency of the first and second living hinges to a second resiliency greater than the first resiliency, wherein the step of increasing the resiliency includes changing a chemical makeup of the material at the first and second living hinges.