Classifications

• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
  • H04R3/00—Circuits for transducers, loudspeakers or microphones
  • H04R3/007—Protection circuits for transducers

Definitions

• the invention relates to an electrical or electronic circuit element free from the phenomenon of electrical micro-discharges.
• C. designates the electrical capacity of the insulating layers immediately in contact with the electrical conductor
• C 2 the conductor capacity - reference voltage or ground
• e designates a spark gap "causing" the phenomenon of micro-discharge.
• the variable voltage recorded at the terminals of the electrical capacitance C : of the layers immediately in contact with the electrical conductor is represented in FIG. This tension testifies to the existence of very rapid relaxation oscillations whose recurrence frequency disturbs the audio frequency signal.
• the solution adopted in the above-mentioned French patent application No. 96 12369 to eliminate this phenomenon consists in applying a coating of semiconductor material on the external surface of the electrical conductor, whether or not provided with its layer. insulating.
• the linear resistivity of the applied semiconductor material is chosen within a range of values adapted so as to allow both the maintenance of the external surface of the electrical conductor at a static electrical potential of constant local value close to that of the electrical conductor and d 'absorb all the erratic electric discharge currents caused by parasitic micro-discharge phenomena.
• the operating mode corresponding to the aforementioned adopted solution therefore consists in attenuating the value of the radiated electric fields during the appearance, which is substantially erratic, of these interface micro-discharges, and, consequently, in suppressing their perceptible degrading effects. the quality of the sound reproduction.
• the present invention relates to the implementation of electrical or electronic circuit elements free from phenomena of electrical micro-discharges, in which the phenomena of discharge are substantially suppressed and not simply attenuated.
• Another object of the present invention is the implementation of electrical or electronic circuit elements, free from phenomena of electrical micro-discharges, these electrical or electronic circuit elements more particularly using, usually, bare electrical conductors, that is to say having no added dielectric electrical insulator.
• the electrical / electronic circuit element which is the subject of the present invention is particularly remarkable in that it comprises a sealed enclosure, comprising at least a first and a second external electrical connection terminal, this sealed enclosure delimiting an empty space consisting at a residual gas pressure below a determined value.
• an electrical circuit is provided, which is internally connected to the first and to the second electrical connection terminal. This makes it possible to substantially eliminate the phenomena of electrical micro-discharges which may appear in the vicinity of the electrical circuit.
• the electrical / electronic circuit element, object of the present invention finds application in the production of electrical / electronic components capable of use in any field of electrical or electronic construction.
• FIG. 2a shows an electrical or electronic circuit element according to the object of the present invention
• FIG. 2b shows, purely by way of illustration, an alternative embodiment of the electrical or electronic circuit element shown in Figure 2a;
• Figure 2c shows a particular non-limiting embodiment of the electrical or electronic circuit element, object of the present invention, shown in Figure 2b;
• FIG. 3a represents a first specific, non-limiting embodiment of an electrical or electronic circuit element in accordance with the object of the present invention, relating to an adjustable electrical capacitor;
• FIG. 4 represents a second specific, non-limiting embodiment of an electrical or electronic circuit element in accordance with the object of the present invention, relating to a filter for rejecting harmonic frequencies from the power sector;
• FIG. 5 shows a specific electrical or electronic circuit element, according to the object of the present invention, corresponding to an electrical capacitor provided with a spark gap.
• the electric or electronic circuit element, object of the invention comprises a sealed enclosure 1 comprising at least a first and a second electrical connection terminal, referenced 10 and 11, external.
• the sealed enclosure 1 delimits an empty space, this empty space being defined as consisting of a residual gas pressure below a determined value.
• an electrical circuit 2 is electrically connected internally to the first 10 and to the second terminal 11 of electrical connection. It is added that, in the case of FIG. 2a, the above-mentioned electric circuit 2 is shown in a non- limiting by a self-inductance for example.
• the electrical or electronic circuit element, object of the present invention comprises above all an electrical circuit, which, in general, is stripped.
• this electrical circuit in accordance with conventional prior techniques is placed in air at atmospheric pressure, the gas mixture, consisting of air, of course constitutes an insulating dielectric, but certain molecules of gas adsorbed at the surface external of the conductive element of the electrical circuit cause in particular the phenomenon of electrical micro-discharges and in particular of interface micro-discharges at the interface between the free or external surface of the electrical conductor constituting the electrical circuit and the sleeve d air surrounding this electrical conductor.
• the confinement of the electrical circuit 2 in a vacuum enclosure makes it possible, during operation, to substantially eliminate the phenomena of electrical micro-discharges and therefore of interface micro-discharges likely to appear in the vicinity of the above-mentioned electrical circuit.
• the pressure p residual pressure of gas contained in the sealed enclosure 1, for a mono-atomic gas or for a mixture of gases such as air, is chosen to be less than 10 "3 mHg. It is recalled that 1 mmHg corresponds to a pressure of 133.42 N / m 2 .
• the sealed enclosure 1 can be constituted by a rigid base, bearing the reference 1a, and a cover or a capsule 1b making it possible to define the sealed enclosure.
• the electrical connection terminals, first 10 and second terminal 11, correspond to waterproof electrical bushings for example.
• the base 1a and the cover 1b are sealed by means of a waterproof sealant for example.
• the top of the cover lb can then include an outlet socket V allowing the vacuum to be carried out in the sealed enclosure 1, this outlet then being sealed while the electrical circuit 2 has been placed inside the sealed enclosure 1 and that the vacuum, that is to say the residual pressure, has been caused.
• the technique for manufacturing vacuum tubes known in electronics, can be used to produce the electrical or electronic circuit elements, objects of the present invention.
• the sealed enclosure 1 can be made of a dielectric material such as glass, quartz, plastic materials or metallic materials.
• any type of electrical circuit can constitute the electrical or electronic circuit element, object of the present invention, for the purpose of eliminating the phenomena of interface micro-discharges previously mentioned.
• these reactive circuits can be constituted for example by pure inductors, at the value of residual resistance near each inductor, or, on the contrary, in specific modes of application advantageous, by electrical capacitors, as will be described below in conjunction with FIGS. 2b to 2d and following.
• the electrical circuit 2 comprises a first 20 and a second 21 armature forming an electrical capacitor, the armature 20 being connected to the connection terminal 10 and the armature 21 to the connection terminal 11.
• the armature 20 being connected to the connection terminal 10 and the armature 21 to the connection terminal 11.
• FIG. 2b there is shown non-contiguous reinforcements nested so as to conventionally constitute a high-value capacitor.
• the armatures 20 and 21 are fixed to form a fixed electric capacitor for example.
• FIG. 2c another particular embodiment of a fixed electric capacitor has been shown in which the armatures 20 and 21 are produced in the form of metallic sheets wound so as to, for electric capacitors of determined capacity, reduce the volume occupied by the whole. It is understood under these conditions that the technology for manufacturing the wound capacitors can be used without difficulty.
• circuit element object of the present invention, it can, in a preferred embodiment, be arranged so as to produce and form, for example, an adjustable electric capacitor.
• an adjustable electric capacitor Such an embodiment is shown in Figures 3a and 3b.
• at least one of the frames, the frame 20 for example, is movable relative to the other frame, the frame 21.
• the mobile armature 20 is mounted so as to be able to rotate about a fixed axis 10a secured to the fixed armature 20 by means of an insert 20a, which is engaged on a threading of the above-mentioned fixed axis 10a.
• the fixed axis 10a is integral with the first connection terminal 10 and can advantageously constitute an extension of the latter.
• the first connection terminal 10 is then cylindrical and of revolution around the axis of symmetry of revolution XX of the assembly.
• the insert 20a can be constituted by a piece of brass for example, which ensures a suitable mounting for rotation of the assembly on the threaded part of the fixed axis 10a.
• the movable armature 20 can then be constituted, as shown in FIG. 3b, by a half-cylinder comprising a plurality of concentric half-cylinders, the concentric half-cylinders being connected by an upper plate 200 secured to the insert 20a mentioned above.
• the fixed armature 21 can be constituted by a vertical half-cylinder constituted by a plurality of concentric vertical half-cylinders, the vertical walls of the concentric vertical half-cylinders constituting the movable armature 20 and the fixed armature 21 being nested, as shown in FIG. 3a, to form a blade capacitor for example.
• the lower part of the vertical half-cylinders constituting the fixed frame 21 is connected by a semicircular metal plate, as shown in FIG. 3b, bearing the reference 210, this plate having a central orifice mounted on a cylindrical part or ring added in Teflon 10b mounted on the fixed axis 10a and, of course, on the first connection terminal 10.
• the mechanical and electrical connection between the second connection terminal 11 and the fixed frame 21 is produced by means of the aforementioned metal plate 210.
• the movable frame 20 comprises, integral with this movable frame via the insert 20a, a permanent magnet 20b polarized north-south and extending substantially in the direction of rectilinear edge of the semicircular plate 200 constituting the movable frame 20.
• the permanent magnet 20b constitutes a mark for the position of the rectilinear edge of the semicircular plate 200 and , finally, a relative position mark of the engagement of the movable armature 20 with respect to the movable armature 21 previously described, and therefore of the adjustment of the value of the capacity of the adjustable electric capacitor thus formed.
• the circuit element, object of the present invention comprises, outside the sealed enclosure 1, a south-north bipolar magnetic circuit, which allows the movement in rotation of the permanent magnet 20b polarized north-south and of the movable armature 20. It is thus understood that the assembly makes it possible to adjust the value of the adjustable electric capacitor as a function of the position of the permanent magnet 20b, which drives in rotation, via the insert 20a, the movable frame 20.
• the sealed enclosure 1 can be provided, outside of the latter, with a support 4, substantially circular or cylindrical support disposed at the top of the capsule 1b, the support 4 comprising for example advantageously a cover 40 mounted for rotation by means of a sliding track 41.
• the south-north bipolar magnetic circuit 3 is engaged in the cover 40 according to a diameter of the latter for example, the assembly constituted by the cover 40 and the bipolar magnetic circuit 3 thus being mounted for rotation about the axis of rotation XX.
• the north pole and the south pole of the south-north bipolar magnetic circuit 3 are brought opposite the south pole and the north pole respectively of the permanent magnet 20b, the assembly thus constituted by the cover 40 and the south-north bipolar magnetic circuit 3 movable in rotation about the axis XX making it possible to drive the assembly constituted by the permanent magnet 20b and the movable armature 20 to ensure adjustment of the adjustable electric capacitor thus formed.
• the cover 40 can thus constitute a knurled knob for adjusting the value of the capacity of the above-mentioned adjustable electric capacitor.
• the electric or electronic circuit element, object of the present invention is not limited to the use of electric capacitors.
• FIG. 4 represents an application of the invention to an electrical or electronic circuit element in the case where the electrical circuit 2 is constituted by a filter rejecting harmonic frequencies from the power sector.
• such a circuit comprises the sealed enclosure 1 comprising five electrical connection terminals, that is a first 10 and a second 11 input terminal normally connected to the supply sector in operation, as well as a first 12 and a second 13 output terminal and a reference voltage terminal 14, that is to say a reference voltage terminal intended to be connected to the ground voltage of the device supplied by the sector.
• the electrical circuit 2 is a quadrupole electrical circuit plus reference voltage, which then forms a frequency-rejecting filter.
• this frequency rejection filter comprises a first L A and a second L 3 self-inductance each interconnected at one of their ends to the first 10 and to the second 11 input terminal respectively, as well as a first C A and a second C 3 electric capacitor connected in series.
• the branch formed by the first C A and the second C B electric capacitor is connected to the other end of the first and of the second self-inductance L ⁇ , respectively L 3 , and the other end of the first and of the second self-inductance L A and L 3 respectively is connected to the first 12, respectively to the second 13 output terminal, while the midpoint of the branch formed by the electric capacitors C A and C 3 is connected to the terminal of reference voltage 14.
• vacuum encapsulation of electrical circuits in accordance with the subject of this document invention relates to all types of electrical circuits as mentioned above.
• the electrical or electronic components concerned are bare electrical conductors, that is to say having no added insulating layer because electrical discharges or micro-discharges at the conductor-insulator interface are liable then to happen.
• the electric circuit element free of micro-discharges when this corresponds to an electric capacitor, can then be placed at critical places in a circuit where micro-discharges and other high frequency parasites are liable to create disastrous phenomena, in particular at the input and output of the amplifiers, at the level of the compensation capabilities or of the feedback correction capabilities.
• the vacuum does not propagate sound disturbances, it is then quite possible to provide a higher vacuum, the circuit elements thus obtained, when these form capacitors, which can then be installed in the speaker filters and even at the terminals of the speakers themselves for which the drive coils are particularly generating micro-discharges.
• the electrical or electronic circuit elements, objects of the present invention, forming capacitors can be systematically associated with capacitors of greater value, added air or dielectric capacitors, the electrical or electronic circuit elements forming capacitors in accordance with the object of the present invention then making it possible to filter and absorb the micro-charges generated by the conventional capacitors with which they are associated.
• an electrical or electronic circuit element forming a capacitor in accordance with the object of the present invention may be associated with a spark gap calibrated inside the sealed enclosure 1, as shown in FIG. 5.

Landscapes

• Physics & Mathematics (AREA)
• Engineering & Computer Science (AREA)
• Acoustics & Sound (AREA)
• Signal Processing (AREA)
• Filters And Equalizers (AREA)
• Coils Or Transformers For Communication (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=9506971

Family Applications (1)

Country Status (6)

Cited By (1)

Families Citing this family (1)

Family Cites Families (6)

• 1997
  • 1997-05-16 FR FR9706045A patent/FR2763469B1/fr not_active Expired - Fee Related
• 1998
  • 1998-05-05 TW TW87106887A patent/TW382722B/zh not_active IP Right Cessation
  • 1998-05-12 AU AU76626/98A patent/AU7662698A/en not_active Abandoned
  • 1998-05-12 EP EP98924420A patent/EP0976300A1/de not_active Ceased
  • 1998-05-12 WO PCT/FR1998/000944 patent/WO1998053639A1/fr not_active Application Discontinuation
  • 1998-05-12 JP JP55002698A patent/JP2001526014A/ja active Pending

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events