Described embodiments include a microelectromechanical system (MEMS) array comprising a first MEMS device that includes a first movable electrostatic plate elastically connected to a first structure, the first movable electrostatic plate having a first mass, a first fixed electrostatic plate, and a first drive circuit having a first drive output coupled to the first fixed electrostatic plate. There is a second MEMS device that includes a second movable electrostatic plate elastically connected to a second structure, the second movable electrostatic plate having a second mass that is different than the first mass, a second fixed electrostatic plate, and a second drive circuit having a second drive output coupled to the second fixed electrostatic plate.

Described embodiments include a microelectromechanical system (MEMS) array comprising a first MEMS device that includes a first movable electrostatic plate elastically connected to a first structure, the first movable electrostatic plate having a first mass, a first fixed electrostatic plate, and a first drive circuit having a first drive output coupled to the first fixed electrostatic plate. There is a second MEMS device that includes a second movable electrostatic plate elastically connected to a second structure, the second movable electrostatic plate having a second mass that is different than the first mass, a second fixed electrostatic plate, and a second drive circuit having a second drive output coupled to the second fixed electrostatic plate.

A capacitor provides a plurality of selectable capacitance values, by selective connection of six capacitor sections of a capacitive element each having a capacitance value. The capacitor sections are provided in a plurality of wound cylindrical capacitive elements. Two vertically stacked wound cylindrical capacitance elements may each provide three capacitor sections. There may be six separately wound cylindrical capacitive elements each providing a capacitor section. The capacitor sections have a common element terminal.

A capacitor provides a plurality of selectable capacitance values, by selective connection of six capacitor sections of a capacitive element each having a capacitance value. The capacitor sections are provided in a plurality of wound cylindrical capacitive elements. Two vertically stacked wound cylindrical capacitance elements may each provide three capacitor sections. There may be six separately wound cylindrical capacitive elements each providing a capacitor section. The capacitor sections have a common element terminal.

The present invention relates to a vacuum capacitor (1, 30) comprising an enclosure (9) to contain a vacuum dielectric medium, a first electrode (12) and a second electrode (13) separated by said vacuum dielectric medium, the enclosure (9) comprising a first conductive collar (2) in electrical contact with the first electrode (12) and a second conductive collar (3) in electrical contact with the second electrode (13), the first conductive collar (2) and the second conductive collar (3) being separated by an insulating element (4) of the enclosure (9), wherein the enclosure (9) exhibits at least one protruding edge (6), said protruding edge (6) being in electrical contact with the closest of the first conductive collar (2) or the second conductive collar (3), wherein the vacuum capacitor (1, 30) comprises at least one protection means (7, 37) covering on the outside of the vacuum enclosure the protruding edge (6), wherein the protection means (7, 37) is made at least partially of an elastomer, wherein at least the outer surface (7b, 37b) of the protection means (7, 37) is electrically conductive and is at the same electrical potential as the closest conductive collar to the protruding edge (6), and wherein the outer surface (7b, 37b) of the protection means (7, 37) has a radius of curvature greater than the radius of curvature of the protruding edge (6).

A vacuum variable capacitor includes a pre-vacuum enclosure for reducing a pressure differential across the bellows, wherein a drive is disposed outside the enclosures of the vacuum variable capacitor. The vacuum force load on the drive system can thereby be reduced, allowing faster movement of the movable electrode, faster capacitance adjustment of the vacuum variable capacitor and longer lifetimes of the device.

The present invention relates to a vacuum capacitor (1, 30) comprising an enclosure (9) to contain a vacuum dielectric medium, a first electrode (12) and a second electrode (13) separated by said vacuum dielectric medium, the enclosure (9) comprising a first conductive collar (2) in electrical contact with the first electrode (12) and a second conductive collar (3) in electrical contact with the second electrode (13), the first conductive collar (2) and the second conductive collar (3) being separated by an insulating element (4) of the enclosure (9), wherein the enclosure (9) exhibits at least one protruding edge (6), said protruding edge (6) being in electrical contact with the closest of the first conductive collar (2) or the second conductive collar (3), wherein the vacuum capacitor (1, 30) comprises at least one protection means (7, 37) covering on the outside of the vacuum enclosure the protruding edge (6), wherein the protection means (7, 37) is made at least partially of an elastomer, wherein at least the outer surface (7b, 37b) of the protection means (7, 37) is electrically conductive and is at the same electrical potential as the closest conductive collar to the protruding edge (6), and wherein the outer surface (7b, 37b) of the protection means (7, 37) has a radius of curvature greater than the radius of curvature of the protruding edge (6).

The present invention relates to an electrode unit (10, 20) for an electric vacuum capacitor comprising a band-shaped capacitor plate (11, 21) with a height H, wherein the band-shaped capacitor plate (11, 21) is wound in a spiral with a maximum diameter D.sub.max and a constant distance between successive turns, wherein the band-shaped capacitor plate (11, 21) comprises a first longitudinal edge (11a, 21a) attached to a supporting part (12) and a second longitudinal edge (11b, 21b), the second longitudinal edge (11b, 21b) being free, wherein at the outer extremity of the spiral, the first longitudinal edge (11a, 21a) and the second longitudinal edge (11b, 21b) are connected by an inclined edge (11c, 21c) such that the first longitudinal edge (11a, 21a) is longer than the second longitudinal edge (11b, 21b), wherein the inclined edge (11c, 21c) forms with the longitudinal axis (B) of the band-shaped capacitor plate (11, 21) an angle α less than or equal to an angle α.sub.max=(45°.Math.π/180°). The invention relates also to a vacuum capacitor (30) comprising at least one electrode unit (10, 20) according to the present invention.

An electrostatic transducer (1) includes: an insulator sheet (11); a first electrode sheet (12); a lead (30); a first bonding part (61), electrically bonding the first electrode sheet (12) with a core wire (30a) of the lead (30) in a first area (Pa) where the first electrode sheet (12) and the core wire (30a) of the lead (30) are disposed overlapping each other; and a second bonding part (62), bonding the insulator sheet (11) with a coating (30b) of the lead (30) in a second area (Pb) where the insulator sheet (11) and the coating (30b) of the lead (30) are disposed overlapping each other.

A capacitor provides a plurality of selectable capacitance values, by selective connection of six capacitor sections of a capacitive element each having a capacitance value. The capacitor sections are provided in a plurality of wound cylindrical capacitive elements. Two vertically stacked wound cylindrical capacitance elements may each provide three capacitor sections. There may be six separately wound cylindrical capacitive elements each providing a capacitor section. The capacitor sections have a common element terminal. A pressure interrupter cover assembly is sealingly secured to the open end of case for the elements and has a deformable cover with a centrally mounted common cover terminal and a plurality of section cover terminals mounted at spaced apart locations. A conductor frangibly connects the common element terminal of the capacitor section to the common cover terminal and conductors respectively frangibly connect the capacitor section terminals to the section cover terminals. Deformation of the cover caused by failure of the capacitor element breaks at least some of the frangible connections sufficient to disconnect the capacitive element from an electric circuit in which it is connected. A cover insulation barrier mounted on the deformable cover, has a barrier cup substantially surrounding the common cover terminal and a plurality of barrier fins each extending radially outwardly from the barrier cup, and deployed between adjacent section cover terminals.