Abstract: A key switch and resilient actuator assembly that includes an electrical switching region and a hollow open ended actuator cover of elastomeric material overlaying the switching region with the open end of the actuator cover in surrounding relationship with the switching region. The actuator cover includes a first wall portion shaped to provide substantially linear resistive force during compression displacement of the cover toward the switching region and to provide substantially linear restoring force during expansion displacement of the actuator cover away from the switching region. The actuator cover further includes a second wall portion shaped to undergo buckling toward the switching region at a predetermined compression displacement and to undergo unbuckling away from the switching region at a predetermined expansion displacement that is smaller in total displacement than the predetermined compression displacement.

Abstract: Apparatus for controlling the feeding of paper about a printer platen. Controlled are paper aligning, rear roller feeding, front roller feeding and paper bail operation. The apparatus is primarily made up of a rocker button, reed switches, a drive motor, a cam gear, a comb, and a paper bail. Upon operator manipulation of the rocker button, the drive motor is turned on for rotating the cam gear. Rotation of the cam gear effects bi-directional rotation of the comb and a paper bail arm carrying the paper bail. Rotation of the comb in a first direction results in (1) a rear feed roller being displaced from the platen to provide a feeding path for paper when inserted into the printer, and (2) a paper aligner being positioned for aligning the paper. Rotation of the comb in a second direction results in the rear feed roller causing engagement of the paper and platen and the paper aligner being brought out of the feeding path of the paper.