An electrical parking brake device includes an operation switch and a control circuit. The operation switch includes a switch button, miniature switches, operation switch terminals and inside conductors, the switch button being in one of an On state, an Off state and a neutral state, the miniature switches operating in conjunction with the state of the switch button. The control circuit includes control circuit terminals, a switch verification circuit, management circuitry and brake application command circuitry, the management circuitry managing the electrical parking brake device. The operation switch defines closed circuits that are independent in terms of a pair of the operation switch terminals, for each of the operating states. The closed circuits are closed circuits that, when one or more of the miniature switches fail, avoids influence of the failure, by the miniature switches other than the one or more failing miniature switches.

A safety circuit for an elevator system includes a first circuit having a plurality of switching contacts and a second circuit having a plurality of switching contacts. The switching contacts of the first circuit are connected in series, and the switching contacts of the second circuit are connected in parallel. Each switching contact of the first circuit is associated with a different switching contact of the second circuit. The switching contacts that are associated with each other are in opposite switching states.

A button structure comprises a base layer, a supporting structure arranged on the base layer, an elastic film layer, the elastic film layer covering the support structure and connected to the support structure, the support structure and the elastic film layer defining a cavity above the base layer, a first upper electrode arranged on the lower surface of the elastic film layer and located in the cavity, a first lower electrode, arranged on the base layer and located in the cavity, and a first variable resistance elastic body between the first upper and first lower electrodes, either arranged on the lower surface of the first upper electrode or arranged on the upper surface of the first lower electrode. When the elastic film layer is elastically deformed in the direction of the base layer, the first variable resistance elastic body connects the first upper electrode with the first lower electrode so as to generate a first signal related to the elastic deformation of the first variable resistance elastic body.