Abstract: A pushbutton switch has a housing with a reciprocating plunger. The plunger is made in two parts with a hollow insert pressed in place to provide a slot inside the plunger with a longitudinally extending portion and a spirally extending portion. A rotatable shaft fits within the hollow insert and has a plurality of teeth at the lower end of the shaft. An electrical contact member with three circumferentially extending fingers is on the shaft over the teeth and with the fingers extending downwardly for contacting three electrical terminals in the housing to which contact may be made by external leads. When the plunger of the switch is depressed, the shaft moves downwardly and rotates without rotating the electrical contact member. When the plunger is released, the shaft also moves upwardly and rotates in the reverse direction whereupon a tooth engages a pawl extending downwardly from the contact member, advancing the contact member in rotation and changing the state of the switch.

Abstract: A pushbutton switch has a housing with a reciprocating plunger. The plunger is made in two parts with a hollow insert pressed in place to provide a slot inside the plunger with a longitudinally extending portion and a spirally extending portion. A rotatable shaft fits within the hollow insert and has a plurality of teeth at the lower end of the shaft. An electrical contact member with three circumferentially extending fingers is on the shaft over the teeth and with the fingers extending downwardly for contacting three electrical terminals in the housing to which contact may be made by external leads. When the plunger of the switch is depressed, the shaft moves downwardly and rotates without rotating the electrical contact member. When the plunger is released, the shaft also moves upwardly and rotates in the reverse direction whereupon a tooth engages a pawl extending downwardly from the contact member, advancing the contact member in rotation and changing the state of the switch.

Abstract: A pushbutton has a body including a barrel and a plunger longitudinally movable in the barrel. A plurality of longitudinally extending teeth on the plunger engage a plurality of longitudinally extending teeth on a rotatable ratchet coaxial with the plunger. The ratchet is spring loaded against the plunger. A rotatable electrical contact cup connected to the ratchet makes or breaks contact with a fixed electrical terminal in the body. The plunger teeth each include a driving face which causes rotation of the ratchet. The driving face has an angle from a normal to the longitudinal direction of the plunger wherein the angle is at least the arctangent of the coefficient of friction between the ratchet teeth and the plunger tooth plus the arctangent of the effective coefficient of friction between electrical contacts in the switch, plus a margin of safety greater than the arctangent of the effective coefficient of friction between other parts of the switch. The angle is up to about 30 degrees.