Abstract: A switching module for use in a high voltage switch includes: a vacuum interrupter (VI), an elastomeric insulating sleeve disposed around the VI; an insulating housing molded around the VI and the sleeve; and a pair of grading capacitors. Each grading capacitor includes an inner and an outer electrode while insulation between the electrodes is solid insulation of the housing molded at the time when the housing is molded. One of the electrodes is galvanically connected to the fixed contact through a first terminal in the switching module and the other electrode is galvanically connected to the moving contact through a second terminal in the switching module. The capacitance of the first grading capacitor is substantially equal to the capacitance of the second grading capacitor.

Abstract: A maximal modifiable modular capacitor-generator (CAPGEN) architecture, dielectrics and electrodes may be modified and retain substantially all of the starting activated carbon powder surface area by encapsulating the activated carbon powder in a modifiable gaseous medium and pressure. The capacitor electrical conductivity may be further increased and resistance reduced by electrically reticulating the electrodes and/or modifying the carbon electrode with rarefied or pressurized gases, conventional electrolytes, radioisotopes, stratified radiation emitting materials such as gases, liquids, solids, or modified photovoltaic carbon powder, thereby the capacitor becomes self charging and the surface area, mass, voltage, capacitance, energy density, power density and working temperature are maximized so that the same capacitor base architecture may be maximally modified from a capacitor to a CAPGEN, to a photovoltaic-thermionic CAPGEN and helium generator.

Abstract: A vacuum variable capacitor includes a pre-vacuum enclosure for reducing a pressure differential across the bellows. 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.

Abstract: An NMR probe head has a capacitor with a dielectric (5), which surrounds a cavity (15) in which a capacitor piston (7) is disposed. A sliding bush (9) has a through hole (16) in which a piston operating rod (8) extends. The piston operating rod (8) is connected to a piezo-electric actuator and to the capacitor piston (7) in such a way that it displaces the capacitor piston linearly when a sawtooth voltage is applied to the piezo-electric actuator. The sliding bush thereby applies braking friction to the piston operating rod during linear displacement of the capacitor piston and only allows the piston operating rod to slide through during the steep edges of the sawtooth voltage. This avoids the disadvantages of prior art, wherein the NMR probe head remains compact and the material cost and manufacturing complexity are reduced.

Abstract: An electronic component comprising a first electrode, a second electrode, and a plurality of ball spacers is disclosed. The first electrode includes a plurality of first through holes formed according to a pattern. The second electrode includes a plurality of second through holes formed according to the pattern. Conductive surfaces of the first and second electrode face each other and the first through holes align with the second through holes. The plurality of ball spacers is disposed between the first and second electrodes. Each ball spacer is disposed between and partially disposed within pairs of aligned through holes.

Abstract: An embodiment of a tunable capacitor can include a plurality of capacitors connected in series where at least two capacitors of the plurality of capacitors share a common electrode where the at least two capacitors are in lateral proximity and a bias that is capable of being applied to the at least two capacitors whereby the at least two capacitors vibrate in opposite phase to each other when the bias and an RF signal is applied to the at least two capacitors.

Abstract: An improved overvoltage protection component is provided. The overvoltage protection component has a first internal electrode contained within a dielectric material. The first internal electrode is electrically connected to a first termination and a second internal electrode contained within the ceramic dielectric material is electrically connected to a second termination.

Abstract: A vacuum capacitor includes a fixed electrode, a movable electrode, a movable electrode shaft, a magnetic flux receiving unit, a magnetic flux generating unit and a capacitance control unit. The fixed electrode is formed from a plurality of electrode members in a vacuum casing. The movable electrode is formed from a plurality of electrode members arranged in gaps formed between the electrode members of the fixed electrode in the vacuum casing. The movable electrode shaft supports the movable electrode. Capacitance appearing between the movable electrode and the fixed electrode is varied by rotation of the movable electrode shaft. The magnetic flux receiving unit rotates the movable electrode shaft in the vacuum casing. The magnetic flux generating unit is located outside the vacuum casing and rotates the magnetic flux receiving unit by magnetic attraction. The capacitance control unit rotates the magnetic flux generating unit.

Abstract: A vacuum capacitor includes a fixed electrode, a movable electrode, a movable electrode shaft, a magnetic flux receiving unit, a magnetic flux generating unit and a capacitance control unit. A plurality of electrode members in a vacuum casing form the fixed electrode. The fixed electrode is divided into a plurality of fixed electrodes, and each fixed electrode is lead outside the vacuum casing and electrically connected to each other in series. A plurality of electrode members arranged in gaps between the electrode members of the fixed electrode form the movable electrode. Rotating the movable electrode shaft, which supports the movable electrode, varies capacitance between the movable electrode and the fixed electrode. The magnetic flux receiving unit rotates the movable electrode shaft. The magnetic flux generating unit, located outside the vacuum casing, rotates the magnetic flux receiving unit by magnetic attraction. The capacitance control unit rotates the magnetic flux generating unit.

Abstract: The present invention can easily adjust capacitance of a vacuum capacitor while maintaining a vacuum state in a vacuum chamber of the vacuum capacitor. A fixed electrode 4 is formed by arranging a plurality of flat electrode members 5 in layers at a certain distance in an axial direction of a vacuum chamber 1b. A movable electrode 7 is formed by arranging a plurality of flat electrode members 8 in layers at a certain distance in the axial direction of the vacuum chamber 1b and fixing the electrode members 8 to a movable electrode shaft 9. By rotation of the movable electrode shaft 9, each electrode member 8 is inserted into and extracted from a gap between the electrode members 5 of the fixed electrode 4 in noncontact with the electrode members 5 of the fixed electrode 4. A magnetic flux receiving portion 106b is fixed to a seal member 102 side of a disk member 106a that is provided at the movable electrode shaft 9.

Abstract: An input device includes a movable electrode and a capacitance detection electrode provided on the upper and lower sides of the resin film substrate, respectively. The movable electrode includes a moving section, and an immobile section. The moving section includes a protrusion. The end of the protrusion comes in contact with the upper side of the resin film substrate in an initial state, or is bonded to the upper side of the resin film substrate. The protrusion has a curved shape so that the side surface of the protrusion is depressed relative to a straight line that connects the end and the base of the protrusion having an approximately trapezoidal cross-sectional shape, or at least one step is formed on the side surface of the protrusion, and the width of the protrusion increases stepwise from the end to the base of the protrusion.

Abstract: A novel semiconductor variable capacitor is presented. The semiconductor structure is simple and is based on a semiconductor variable MOS capacitor structure suitable for integrated circuits, which has at least three terminals, one of which is used to modulate the equivalent capacitor area of the MOS structure by increasing or decreasing its DC voltage with respect to another terminal of the device, in order to change the capacitance over a wide ranges of values. Furthermore, the present invention decouples the AC signal and the DC control voltage avoiding distortion and increasing the performance of the device, such as its control characteristic. The present invention is simple and only slightly dependent on the variations due to the fabrication process. It exhibits a high value of capacitance density and, if opportunely implemented, shows a linear dependence of the capacitance value with respect to the voltage of its control terminal.

Abstract: A vacuum capacitor has at least two electrodes in a vacuum, the electrodes being manufactured from, or coated with, aluminium or an aluminium alloy; and the housing of the vacuum capacitor includes an insulating (e.g., ceramic) part and two or more conducting parts.

Abstract: The present invention can easily adjust capacitance of a vacuum capacitor while maintaining a vacuum state in a vacuum chamber of the vacuum capacitor. A fixed electrode 4 is formed by arranging a plurality of flat electrode members 5 in layers at a certain distance in an axial direction of a vacuum chamber 1b. A movable electrode 7 is formed by arranging a plurality of flat electrode members 8 in layers at a certain distance in the axial direction of the vacuum chamber 1b and fixing the electrode members 8 to a movable electrode shaft 9. By rotation of the movable electrode shaft 9, each electrode member 8 is inserted into and extracted from a gap between the electrode members 5 of the fixed electrode 4 in noncontact with the electrode members 5 of the fixed electrode 4. A magnetic flux receiving portion 106b is fixed to a seal member 102 side of a disk member 106a that is provided at the movable electrode shaft 9.

Abstract: A variable capacitive element includes a first fixed electrode and a second fixed electrode that are insulated from each other, a movable electrode arranged to face the first fixed electrode and the second fixed electrode, a dielectric layer provided between the movable electrode and the first fixed electrode as well as the second fixed electrode, a first wiring part for applying a first driving voltage to the first fixed electrode with reference to a potential of the movable electrode, and a second wiring part for applying a second driving voltage to the second fixed electrode with reference to the potential of the movable electrode, the second driving voltage having a polarity different from a polarity of the first driving voltage.

Abstract: A MEMS device comprises first and second opposing electrodes (42,46), wherein the second electrode (46) is electrically movable to vary the electrode spacing between facing first sides of the first and second electrodes. A first gas chamber (50) is provided between the electrodes, at a first pressure, and a second gas chamber (52) is provided on the second, opposite, side of the second electrode at a second pressure which is higher than the first pressure. This arrangement provides rapid switching and with damping of oscillations so that settling times are reduced.

Abstract: At least one of the conductive members has a hollow storage portion that is formed at the conductive member and a communication hole through which the storage portion and the vacuum chamber communicate with each other, a getter is set inside the storage portion, and an adsorbed object such as metal particles and gas in a vacuum chamber is adsorbed by the getter. By prevent application of the electric field to the getter, even though the electric field appears in a vacuum casing, a temperature of the getter does not reach a re-release temperature, and also electron stimulus desorption phenomenon does not occur, then it is possible to prevent the metal particles and the gas etc. which have been adsorbed once by the getter from being released.

Abstract: A varactor element, includes: a dielectric layer; a pair of signal electrodes, each disposed on one face of the dielectric layer and facing each other; and a pair of control electrodes, each disposed on another face of the dielectric layer and facing each other parallel to a direction intersecting a direction of the pair of signal electrodes facing each other.

Abstract: A MEMS device of an aspect of the present invention including a MEMS element includes a first lower electrode provided on a substrate, a first insulator which is provided on the upper surface of the first lower electrode, and has a first thickness, and a movable first upper electrode supported by an anchor in midair above the first lower electrode, and a capacitance element includes a second lower electrode provided on the substrate, a second insulator which is provided on the upper surface of the second lower electrode, and has a second thickness, and a second upper electrode provided on the second insulator, wherein the second thickness is less than the first thickness.

Abstract: A tuneable capacitor arrangement for RF use has two series coupled MEMS variable capacitors (C1,C2;C4,C5,C6,C7), varied according to a control signal. The series coupling enables the capacitor to withstand a higher voltage since this is shared by the individual capacitors in a series coupled arrangement. An increase in size of electrodes for each capacitor is compensated by a reduction in size of the springs supporting movable electrodes. These springs can have a larger stiffness value since the capacitance is larger. This means shorter springs, which can also result in a reduction in problems of stiction, resistance, and slow switching. The capacitances have a fixed and a movable electrode, with the RF signal coupled to the fixed electrode to avoid the springs needing to carry an RF signal. This can reduce the problems of inductance and resistance in the springs.

Abstract: A method of manufacturing capacitive elements for a capacitive device which comprises one or more layers is provided. At least one layer is etched from a first surface to a second surface thereof to form two sections of the layer, such that the sections are movable relative to one another, and such that a wall extending from the first surface to the second surface is formed on each of the two sections, the walls defining a gap therebetween. An etching step forms multiple recesses in each wall such that multiple capacitive elements are defined between adjacent recesses, the capacitive elements of one wall being offset from those of the other wall when the sections are stationary with respect to one another. A corresponding capacitive device is also provided.

Abstract: An array variable capacitor apparatus includes a line unit including a ground line and a signal line which operates as a lower electrode; and a plurality of plates which are engaged with the line unit to generate capacitance and which operate as upper electrodes, the plurality of plates being arranged in an array pattern and having different degrees of stiffness.

Abstract: A variable capacitor including a first electrode part, which is provided at a fixed part that includes a substrate, and a movable part, which has a second electrode part forming the capacity of said variable capacitor between itself and the first electrode part, and the movable part is displaced in response to a first drive signal to selectively go into an opposing status, in which the second electrode part opposes the first electrode part, and a non-opposing status, in which the second electrode part essentially does not oppose the first electrode part. This variable capacitor is able to obtain at least a two-value capacity in which the mutual ratio is large without specially requiring another capacitor or a switch, and it is able to obtain the desired capacity variation range by combining a plurality of capacitors.

Abstract: A micro fluidic device and method for capacitive sensing. The device includes a fluid channel including an inlet at a first end and an outlet at a second end, a cavity region coupled to the fluid channel, and a polymer based membrane coupled between the fluid channel and the cavity region. Additionally, the device includes a first capacitor electrode coupled to the membrane, a second capacitor electrode coupled to the cavity region and physically separated from the first capacitor electrode by at least the cavity region, and an electrical power source coupled between the first capacitor electrode and the second capacitor electrode and causing an electric field at least within the cavity region. The polymer based membrane includes a polymer.

Abstract: A mechanical drive system for a vacuum capacitor is provided and includes a drive screw and a nut, wherein the nut is arranged in a housing of the vacuum capacitor, wherein the drive screw is screwed through the nut, wherein a first electrode is arranged on one side of the drive screw, wherein, by a rotation of the drive screw, the first electrode is movable relative to a second electrode, and wherein the nut is at least partially manufactured out of a plastic material.

Abstract: A microfluidic device and method for capacitive sensing. The device includes a fluid channel including an inlet at a first end and an outlet at a second end, a cavity region coupled to the fluid channel, and a polymer based membrane coupled between the fluid channel and the cavity region. Additionally, the device includes a first capacitor electrode coupled to the membrane, a second capacitor electrode coupled to the cavity region and physically separated from the first capacitor electrode by at least the cavity region, and an electrical power source coupled between the first capacitor electrode and the second capacitor electrode and causing an electric field at least within the cavity region. The polymer based membrane includes a polymer.

Abstract: Capacitors (10,20,40,50,70,80) having a fluid dielectric material that is transported or undergoes a phase change are disclosed. The dielectric medium change results in a change in the total dielectric constant of the material between the electrodes (12, 14, 72, 74, 81, 82), thus changing the capacitance of the capacitors. Transporting or phase changing the dielectric fluids into and out of a the electric field of the capacitor, changes the effective dielectric constant and the capacitance of the capacitor.

Abstract: A device for varying the capacitance of an electronic circuit is disclosed. The device comprises a flexible membrane located above the electronic circuit, a metal layer connected to the flexible membrane, and bias circuitry located above the membrane. Variation of the capacitance of the electronic circuit is obtained by pulling the membrane upwards by means of the bias circuitry. The disclosed device provides a sizeable capacitance variation and high Q factor, resulting in overall low filter insertion loss. A nearly constant group delay over a wide operating bandwidth is also obtained.

Abstract: The disclosure describes a variable capacitor device, which is formed by a linear motor and a variable capacitor having at least one stator electrode and a movable electrode. A piezoelectric transducer of the linear motor is frictionally coupled to the movable electrode. Application of electrical signals to the piezoelectric transducer of the linear motor produces a motion of the surface of the piezoelectric transducer. The frictional coupling between the piezoelectric transducer surface and the movable electrode transmits a fraction of piezoelectric transducer motion to the movable piston electrode thereby changing the capacity of the variable capacitor. The amount and sign of the capacitance change is selectable by the operator through control of the electrical signals applied to the piezoelectric transducer.

Abstract: A vacuum capacitor includes a vacuum vessel, stationary and movable electrodes arranged in the vacuum vessel, and a bellows which follows the movable electrode to maintain the hermeticity of the inside of the vacuum vessel and which serves as a current path, wherein the bellows is formed of a conduction high-strength heat resisting alloy.

Abstract: A vacuum variable capacitor is includes of a vacuum container which is formed by sealing both end of a cylindrical insulator with a fixed-side end plate and a movable-side end plate, a movable conductive member which is disposed opposite to the fixed-side end plate in the vacuum container, a fixed electrode which is provided on the fixed-side end plate, a movable electrode which is provided on the movable conductive member, a bellows provided in the vacuum container, a rotating portion which is rotatably disposed outside of the vacuum container, and a ball screw through which the movable conductive member is supported by the rotating member.

Abstract: A vacuum variable capacitor includes an energization bellows arranged in a vacuum vessel and having ends mounted to a movable-electrode support plate and a movable side-end plate, respectively, a heat shielding bellows arranged inside the energization bellows and outside a slide-guide support and having ends mounted to the movable-electrode support plate and the movable side-end plate, respectively, and a cooling pipe interposed between the two bellows and for preventing transfer of heat generated in the energization bellows.

Abstract: The present invention is directed to a capacitor apparatus of the capacity variable type. This capacitor apparatus is manufactured by Micro Electro-Mechanical System technology, and comprises an insulating substrate (2) in which at least two capacitor electrodes (3), (4) are formed on one surface (2a) in the state where they are insulated each other, an actuator (5) formed by insulating material and having an external shape to bridge over the respective capacitor electrodes (3), (4), the actuator (5) being such that a conductor which respectively constitutes capacitors between the conductor (6) and these capacitor electrodes (3), (4), and drive means (7) for allowing this actuator (5) to undergo an operation to come into contact with one principal surface (2a) of the insulating substrate (2) or to become away therefrom.

Abstract: The present invention is directed to a capacitor apparatus of the capacity variable type. This capacitor apparatus is manufactured by Micro Electro-Mechanical System technology, and comprises an insulating substrate (2) in which at least two capacitor electrodes (3), (4) are formed on one surface (2a) in the state where they are insulated each other, an actuator (5) formed by insulating material and having an external shape to bridge over the respective capacitor electrodes (3), (4), the actuator (5) being such that a conductor which respectively constitutes capacitors between the conductor (6) and these capacitor electrodes (3), (4), and drive means (7) for allowing this actuator (5) to undergo an operation to come into contact with one principal surface (2a) of the insulating substrate (2) or to become away therefrom.

Abstract: A new type of high-Q variable capacitor includes a substrate, a first electrically conductive layer fixed to the substrate, a dielectric layer fixed to a portion of the electrically conductive layer, and a second electrically conductive layer having an anchor portion and a free portion. The anchor portion is fixed to the dielectric layer and the free portion is initially fixed to the dielectric layer, but is released from the dielectric layer to become separated from the dielectric layer, and wherein an inherent stress profile in the second electrically conductive layer biases the free portion away from the dielectric layer. When a bias voltage is applied between the first electrically conductive layer and the second electrically conductive layer, electrostatic forces in the free portion bend the free portion towards the first electrically conductive layer, thereby increasing the capacitance of the capacitor.

Abstract: An integrated, tunable capacitance is specified in which the quality factor is improved by virtue of the fact that, instead of source/drain regions, provision is made of highly doped well terminal regions having a deep depth, for example formed as collector deep implantation regions. This reduces the series resistance of the tunable capacitance. The integrated, tunable capacitance can be used for example in integrated voltage-controlled oscillator circuits in which a high quality factor is demanded.

Abstract: This invention relates to an apparatus and method of using a high frequency, high power, fluid dielectric variable capacitor for an impedance matching network. The apparatus includes of a bow-tie rotary vane, a set of two fixed vanes, and a set of rotating vanes adapted to rotate interdigitally between the fixed vanes. A dielectric fluid is circulated between the fixed vanes and the rotating vanes for cooling the device. This arrangement facilitates production of a device having a higher capacitance and a smaller size, thus making it suitable for use in a matching network.

Abstract: A new type of high-Q variable capacitor includes a substrate, a first electrically conductive layer fixed to the substrate, a dielectric layer fixed to a portion of the electrically conductive layer, and a second electrically conductive layer having an anchor portion and a free portion. The anchor portion is fixed to the dielectric layer and the free portion is initially fixed to the dielectric layer, but is released from the dielectric layer to become separated from the dielectric layer, and wherein an inherent stress profile in the second electrically conductive layer biases the free portion away from the a dielectric layer. When a bias voltage is applied between the first electrically conductive layer and the second electrically conductive layer, electrostatic forces in the free portion bend the free portion towards the first electrically conductive layer, thereby increasing the capacitance of the capacitor.

Abstract: A varactor includes a first capacitor plate, a second capacitor plate, at least one fixed charge holder, and a control electrode. The second capacitor plate is spaced from and movable towards and away from the first capacitor plate. At least one fixed charge holder with an imbedded charge is on at least a portion of the second capacitor plate. The control electrode is spaced from the second capacitor plate. Applying a bias to the control electrode moves the second capacitor plate towards or away from the first capacitor plate depending on the polarity of the applied bias.

Abstract: The invention relates to a bellows in a vacuum capacitor, whose bellows structure (1) comprises a carrier material (2) and at least one electrically conductive layer (5, 6), whereby the latter has a uniform thickness over the entire bellows structure. The deviations of the layer thickness from the mean are less than ±50% and preferably less than ±10%. This results in an increased life span with mechanical loading. In order to increase the heat emission through radiation, the bellows structure (1) has an additional dark layer (7). The used method provides for the application of the electrically conductive layers prior to the shaping process, which results in homogeneous layer thicknesses.

Abstract: A capacitor with protection device is mainly used to distribute power supply, and to protect capacitor load. The invention can not only display electrical characteristics, but also distribute electric power to every loader. Furthermore, it can protect the capacitor and load by a protection device, and it saves the time and money necessary to install a protection element.

Abstract: An improved vacuum variable capacitor can include one or more characteristics that provide advantages over previous vacuum variable capacitors. In particular, the vacuum variable capacitor can be constructed so as to enable the capacitance to be adjusted more easily, reduce parasitic electrical characteristics that degrade the performance of the vacuum variable capacitor, increase the strength of the capacitor plates of the vacuum variable capacitor, reduce the size of the vacuum variable capacitor, and/or make the shape of the vacuum variable capacitor more easily integrated into a system of which the vacuum variable capacitor is part.

Abstract: An adjuster nut is rotatably supported to a vacuum container of a vacuum variable capacitor of a vacuum variable capacitor device. The adjuster nut has a nut portion, and a shank made of an insulating material. The shank has a first end integrated with the nut portion and a second end adapted to be directly coupled with a rotational shaft of a driving portion of the vacuum variable capacitor device. Another type of the adjuster nut has a deformable bellows, a nut portion, and a shank made of an insulating material. A second end of the nut portion is coupled with a first end of the bellows. The shank has a first end coupled with a second end of a bellows, and a second end adapted to be directly coupled with the rotational shaft of the driving portion of the vacuum variable capacitor device.

Abstract: A capacitor for connecting to components within a vacuum system in which the space between the capacitor plates is at the pressure of the vacuum system is provided. One of the be plates provides a feed-through which permits closer coupling of the capacit or to other circuits the system and also eliminates the need for additional components. The capacitor can be a mounted and thus thermally coupled to a vacuum manifold which provides temperature stabilization.

Abstract: A vacuum variable capacitor includes a vacuum bellows for allowing a pressure differential between two volumes inside the capacitor, wherein one of the volumes may be a vacuum volume. The vacuum variable capacitor further includes a conductive bellows disposed within the vacuum volume. In such an arrangement, the materials selected for the vacuum bellows and the conductive bellows may be selected to optimize the function of each bellows.

Abstract: A capacitor is described, in particular a vacuum capacitor, comprising two electrodes (1, 1′), at least one insulator (5), and means for fastening (4, 4′). A process is proposed according to which the two electrodes (1, 1′) are each produced as one piece of an electrode material through a cold-flow extrusion process. The electrodes so produced are distinguished by a high surface quality. The result of this, in the capacitors produced from such electrodes, is high quality-factors, low temperature coefficients, a high current-carrying capacity, and an excellent dielectric strength, as well as a compact structure with a simultaneous reduction in the number of components required. Capacitors of this type, in particular vacuum capacitors, find application in HF technology for fixed and variable capacitance values.

Abstract: The variable capacitor (1) is characterized by the fact that the safety end switches (6, 7) as well as a displacement detector (10) are integrated in the housing (1) or in an additional housing (5) provided at one of the front ends of the capacitor housing (1). Due to this construction, the entire device becomes more compact and more precise in operation.

Abstract: A variable capacitor formed of two flexible interleaved films, each having a dielectric layer and a superposed electrically conductive layer. The films are coiled about an axis in sliding contact with each other and are movable axially relative to each other to vary the capacitance.

Abstract: A method of batch producing capacitive pressure sensors in which a sheet of semiconductive material is provided with an insulating layer 4 on one side thereof and a plurality of cavities 1 are formed in the semiconductive sheet by removing part of the insulating layer and part of the semiconductive sheet. Simultaneously with producing the cavities in the semiconductive sheet, at least one recess is provided, again by removing part of the insulating layer and part of the semiconductive sheet.

Abstract: In an adjustable vacuum condenser, in which two interengaging electrode systems are arranged in a vacuum-tight housing, the upper electrode system of which is displaceably connected with the cover of the housing via a set of bellows serving as current feed, the interfering self-inductivity is reduced by adapting the outside diameter of the set of bellows and the inside diameter of the electrically conducting jacket surrounding the set of bellows to one another.