A dome-shaped push switch includes a sheet and a conducting layer disposed at a low surface of the sheet. The sheet has a pressing portion arching upward. The conducting layer is disposed at a lower surface of the sheet. The conductivity of the sheet is greater than that of the sheet. The pressing portion includes at least one through hole penetrating through the pressing portion. The through hole has a side wall, the side wall sequentially has a shear surface and a tear surface from bottom up, and a fillet is provided between the shear surface and a lower surface of the pressing portion.

A double breaker switch comprises a contact bridge connected to an actuator at a connection point, a first fixed contact, and a second fixed contact. The contact bridge includes a first bridge contact connected to the connection point by a first arm and a second bridge contact connected to the connection point by a second arm. The second arm is longer than the first arm. The first bridge contact electrically connects with the first fixed contact at a first contact point in a closed state of the double breaker switch. The second bridge contact electrically connects with the second fixed contact at a second contact point and a third contact point in the closed state of the double breaker switch.

A vacuum switching device may have at least one cup-shaped contact closed by a disc of contact material and a conical mechanical support, which acts to prevent the contact disc from becoming concave. The cup-shaped contact may include a plurality of slots in the sidewalk that extend into the base of the cup, the slots oriented to produce an axial magnetic field when current flows through the contacts. The support may be made of a metal that is a poor conductor of electricity. The narrow end of the cone may be capped by a circular ring or disc, and the wide end may be formed with a flange. The flange may be circular and may be sized and formed to locate the cone centrally in the base of the contact cup. The cone may have apertures to facilitate the evacuation of gas inside the cone.

A vacuum switching device may have at least one cup-shaped contact closed by a disc of contact material and a conical mechanical support, which acts to prevent the contact disc from becoming concave. The cup-shaped contact may include a plurality of slots in the sidewalk that extend into the base of the cup, the slots oriented to produce an axial magnetic field when current flows through the contacts. The support may be made of a metal that is a poor conductor of electricity. The narrow end of the cone may be capped by a circular ring or disc, and the wide end may be formed with a flange. The flange may be circular and may be sized and formed to locate the cone centrally in the base of the contact cup. The cone may have apertures to facilitate the evacuation of gas inside the cone.

A double breaker switch comprises a contact bridge connected to an actuator at a connection point, a first fixed contact, and a second fixed contact. The contact bridge includes a first bridge contact connected to the connection point by a first arm and a second bridge contact connected to the connection point by a second arm. The second arm is longer than the first arm. The first bridge contact electrically connects with the first fixed contact at a first contact point in a closed state of the double breaker switch. The second bridge contact electrically connects with the second fixed contact at a second contact point and a third contact point in the closed state of the double breaker switch.

A dome-shaped push switch includes a sheet and a conducting layer disposed at a low surface of the sheet. The sheet has a pressing portion arching upward. The conducting layer is disposed at a lower surface of the sheet. The conductivity of the sheet is greater than that of the sheet. The pressing portion includes at least one through hole penetrating through the pressing portion. The through hole has a side wall, the side wall sequentially has a shear surface and a tear surface from bottom up, and a fillet is provided between the shear surface and a lower surface of the pressing portion.