A key entry device including a housing, a keypad array disposed within the housing and including a plurality of keys, a key contact array disposed within the housing below the keypad array and including a plurality of contact pairs, a dome array underlying the keypad array and the key contact array and including a plurality of domes, and a protrusion array underlying the dome array and including a plurality of protrusions, whereby depression of one of the plurality of keys of the keypad array causes a corresponding one of the domes of the dome array to be displaced downwardly and to be deformed by pushing engagement with a corresponding one of the protrusions of the protrusion array into contact with at least one of the contact pairs of the key contact array.

A electromechanical relay device (100) comprising a source electrode (102), a beam (104) mounted on the source electrode at a first end and electrically coupled to the source electrode; a first drain electrode (112) located adjacent a second end of the beam, wherein a first contact (110) on the beam is arranged to be separated from a second contact (112) on the first drain electrode when the relay device is in a first condition; a first gate electrode (106 arranged to cause the beam to deflect, to electrically couple the first contact and the second contact such that the device is in a second condition; and wherein the first and second contacts are each coated with a layer of nanocrystalline graphite.

A key entry device including a housing, a keypad array disposed within the housing and including a plurality of keys, a key contact array disposed within the housing below the keypad array and including a plurality of contact pairs, a dome array underlying the keypad array and the key contact array and including a plurality of domes, and a protrusion array underlying the dome array and including a plurality of protrusions, whereby depression of one of the plurality of keys of the keypad array causes a corresponding one of the domes of the dome array to be displaced downwardly and to be deformed by pushing engagement with a corresponding one of the protrusions of the protrusion array into contact with at least one of the contact pairs of the key contact array.

An electrical switch includes a coil assembly, an armature rotatable about an axis of rotation and driven by the coil assembly, and a contact assembly having a contact spring directly connected to the armature. The contact spring is a spring pack including a plurality of springs. At least one of the springs of the spring pack is formed of a first material and at least another one of the springs of the spring pack is formed of a second material different from the first material.

An electrical contact device includes a high electric potential-side contact and a low electric potential-side contact having a lower electric potential than the high electric potential-side contact. The high electric potential-side contact and the low electric potential-side contact are configured to be brought into and out of contact with each other. At least one of the high electric potential-side contact and the low electric potential-side contact is formed of a low-boiling point material whose boiling point is lower than 2562 C. or a mixed material that contains the low-boiling point material.

A motor starter for operating an electric motor connected to a multiphase power supply includes a semiconductor switch arranged in a current-carrying phase of the multiphase power supply, and an electromechanical switch arranged in parallel relation to the semiconductor switch in the current-carrying phase. The electromechanical switch includes a movable switching piece configured tiltable to reduce a current gradient in the semiconductor switch.

An electrically conductive membrane pressure switch, such as a graphene membrane pressure switch. The electrically conductive membrane pressure switch includes an electrically conductive membrane, source, drain plane, actuator, and movable element (such as a piston element). The actuator drives the movable element to create a pressure differential that moves the suspended section of the electrically conductive membrane between its on, off, and neutral states.

An electrical switch includes a coil assembly, an armature rotatable about an axis of rotation and driven by the coil assembly, and a contact assembly having a contact spring directly connected to the armature. The contact spring is a spring pack including a plurality of springs. At least one of the springs of the spring pack is formed of a first material and at least another one of the springs of the spring pack is formed of a second material different from the first material.

A force activated electrical switch including a conductor that is screen printed on a first base and a conductor that is screen printed on a second base. The switch includes a plurality of nodes of dielectric material printed in a spaced apart pattern on at least one of the bases. The first base is positioned over the second base so that when a downward force is applied to the first base, the distance between at least a portion of the conductors decreases. The switch may be employed in a system that includes a controller operatively connected to the conductors. The controller includes a sensing circuit or processor configured to detect the presence of the occupant when the force is great enough to cause the conductors to contact one another, thereby activating the electrical switch.

Systems and methods for a hack-proof security keyboard are described. In some embodiments, a keyboard module may include a first circuit configured to detect activation of a plurality of keys and a second circuit configured to detect activation of a subset of the plurality of keys, where the second circuit overlies the first circuit. In other embodiments, a method may include detecting an electrical signal received from a secondary membrane of a keyboard, where the keyboard includes a primary membrane configured to detect individual activation of any of a plurality of keys, and where the secondary membrane is configured to output the electrical signal in response to concurrent activation of a subset of the plurality of keys. The method may also include performing a selected action in response to the detection.