A key structure includes a membrane circuit board, an elastic element and a high impedance layer. The membrane circuit board includes a lower plate, an upper plate, a spacer plate and a circuit layer. The upper plate is located over the lower plate. The upper plate has an opening through the upper plate. The spacer plate is arranged between the lower plate and the upper plate. The circuit layer is arranged between the spacer plate and the upper plate. The elastic element is disposed on the membrane circuit board and substantially aligned with opening. The high impedance layer is disposed on a bottom surface of a bottom part of the elastic element and disposed within the opening of the upper plate. The high impedance layer is in contact with a part of the circuit layer.

A switch device includes: an operation unit including a first switch, a second switch, a first resistor, a second resistor, and a first terminal; and a control unit including a second terminal coupled to the first terminal. A series circuit of the first switch and the first resistor and a series circuit of the second switch and the second resistor are coupled between the first terminal and a ground. The control unit monitors a potential of the first terminal which changes in response to on/off of the first and second switches via the second terminal, and determines the operation state of each switch based on the potential. A contact of the first switch is configured of a contact in which a resistance value between contacts at the time of opening and closing changes more sharply as compared with a contact of the second switch.

Systems and methods for identifying relay contact position within an appliance. In one embodiment, an appliance includes a first motor, a second motor, and a relay. The relay can be configured to be adjusted between at least a first position associated with a first circuit of the first motor and a second position associated with a second circuit of the second motor. The appliance can also include one or more control device(s) configured to identify the position of the relay within the appliance. For instance, the control device(s) can provide a test signal to the relay and detect an output signal that is based at least in part on the input signal. The output signal can be associated with the second circuit. The control device(s) can determine whether the relay is in the first position or the second position based at least in part on the output signal.

A redundant and dissimilar system for monitoring the status of contactors of an aircraft control stick. This monitoring system comprises at least one electrical power source, at least one processor and several circuits for monitoring the status of the switches of the contactors. Each monitoring circuit comprises and electrical power source, a switch for each contactor, the switches of a contactor being connected to each other, and an electronic assembly provided with receivers arranged in series with each other. Each switch is arranged in parallel with at least one receiver so as to short-circuit the at least one receiver when the switch is in the closed state. Each processor measures and analyses an electrical feature of the electronic assembly, such as a mains voltage VE as the terminals of the electronics assembly, in order to determine the status of each switch.

The invention relates to a circuit arrangement (100) for evaluating at least two switching states of an actuating element, having a moveable contact means (110) which is connectable to the actuating element, a first evaluation circuit (140a) with a first voltage divider, which has first node points (K1a, K2a, K3a, K4a, K5a) and a first tap (150a) for tapping off a first output signal (A1, A3, A5) of the first evaluation circuit (140a), at least one second evaluation circuit (140b) with a second voltage divider, which has second node points (K1b, K2b, K3b, K4b, K5b) and a second tap (150a) for tapping off a second output signal (A2, A4, A6) of the second evaluation circuit (140b), first contact surfaces (121a, 122a, 123a, 124a, 125a) which are each electrically connected to one of the first node points (K1a to K5a), and second contact surfaces (121b, 122b, 123b, 124b, 125b) which are each electrically connected to one of the second node points (K1b to k5b), wherein via the movable contact means (110), depending on the switching state of the actuating element at least one of the first contact surfaces (121a to 125a) and/or at least one of the second contact surfaces (121b and 125b) are electrically connectable to a predetermined reference potential (P). The invention also relates to a method for operating a circuit arrangement (100), and to a switching device having a circuit arrangement (100).

Apparatuses, systems, and methods of manufacturing are described that provide a rotary switch. An example rotary switch includes a substrate and a plurality of electrical contacts supported by the substrate. The rotary switch includes a resistor network of a plurality of resistors in electrical communication with the plurality of electrical contacts and a commutator that moves relative to the substrate along the plurality of electrical contacts. The commutator electrically connects a pair of adjacent electrical contacts so as to modify an output voltage of the rotary switch corresponding to a position of the rotary switch. Each resistor of the resistor network is positioned so as to electrically connect a respective pair of adjacent electrical contacts. Each resistor in the resistor network comprises a resistance value that is different from resistance values of other resistors in the resistor network.

Apparatuses, systems, and methods of manufacturing are described that provide a rotary switch. An example rotary switch includes a substrate and a plurality of electrical contacts supported by the substrate. The rotary switch includes a resistor network of a plurality of resistors in electrical communication with the plurality of electrical contacts and a commutator that moves relative to the substrate along the plurality of electrical contacts. The commutator electrically connects a pair of adjacent electrical contacts so as to modify an output voltage of the rotary switch corresponding to a position of the rotary switch. Each resistor of the resistor network is positioned so as to electrically connect a respective pair of adjacent electrical contacts. Each resistor in the resistor network comprises a resistance value that is different from resistance values of other resistors in the resistor network.

A redundant and dissimilar system for monitoring the status of contactors of an aircraft control stick. This monitoring system comprises at least one electrical power source, at least one processor and several circuits for monitoring the status of the switches of the contactors. Each monitoring circuit comprises and electrical power source, a switch for each contactor, the switches of a contactor being connected to each other, and an electronic assembly provided with receivers arranged in series with each other. Each switch is arranged in parallel with at least one receiver so as to short-circuit the at least one receiver when the switch is in the closed state. Each processor measures and analyses an electrical feature of the electronic assembly, such as a mains voltage VE as the terminals of the electronics assembly, in order to determine the status of each switch.

A control circuit of a surgical device is disclosed. The control circuit includes a first circuit portion coupled to at least one switch operable between an open state and a closed state. The first circuit portion communicates with a surgical generator over a conductor pair to receive a control signal to determine a state of the at least one switch.

The invention relates to a circuit arrangement (100) for evaluating at least two switching states of an actuating element, having a moveable contact means (110) which is connectable to the actuating element, a first evaluation circuit (140a) with a first voltage divider, which has first node points (K1a, K2a, K3a, K4a, K5a) and a first tap (150a) for tapping off a first output signal (A1, A3, A5) of the first evaluation circuit (140a), at least one second evaluation circuit (140b) with a second voltage divider, which has second node points (K1b, K2b, K3b, K4b, K5b) and a second tap (150a) for tapping off a second output signal (A2, A4, A6) of the second evaluation circuit (140b), first contact surfaces (121a, 122a, 123a, 124a, 125a) which are each electrically connected to one of the first node points (K1a to K5a), and second contact surfaces (121b, 122b, 123b, 124b, 125b) which are each electrically connected to one of the second node points (K1b to k5b), wherein via the movable contact means (110), depending on the switching state of the actuating element at least one of the first contact surfaces (121a to 125a) and/or at least one of the second contact surfaces (121b and 125b) are electrically connectable to a predetermined reference potential (P). The invention also relates to a method for operating a circuit arrangement (100), and to a switching device having a circuit arrangement (100).