FR2561830A1 - METHOD AND DEVICE FOR ELECTRICALLY LOADING AND DISCHARGING AN ELEMENT - Google Patents

Abstract

THE INVENTION RELATES TO A DEVICE FOR ELECTRICALLY CHARGING OR DISCHARGING AN ELEMENT. THE DEVICE INCLUDES A DIELECTRIC ELEMENT 3 OF WHICH ONE SIDE CARRIES AN INDUCTOR ELECTRODE 4 AND THE OPPOSITE SIDE A DISCHARGE ELECTRODE 5 WHICH IS ARRANGED, IN RELATION TO ELECTRODE 4, SO AS TO BE CLOSER TO A LATERAL EDGE OF THE LATTER ON THE OPPOSITE LATERAL EDGE. A SOURCE 6 APPLIES AN ALTERNATIVE VOLTAGE BETWEEN THE INDUCTOR ELECTRODE AND THE DISCHARGE ELECTRODE IN ORDER TO PRODUCE, TO THE SURFACE OF THE DIELECTRIC ELEMENT 3 CARRYING THE DISCHARGE ELECTRODE 5, A AREA OF SURFACE DISCHARGE WHOSE EDGE COINCIDATES SENSITIVELY WITH THE SIDE EDGE OF THE INDUCING ELECTRODE TO WHICH THE DISCHARGE ELECTRODE 5 IS CLOSEST. FIELD OF APPLICATION: ELECTROPHOTOGRAPHY, ELECTROSTATIC RECORDING, ETC.

Description

The invention relates to a method for electrically charging or discharging

  an element and a discharge device embodying this method, the device and method being usable for electrostatic recording, electrophotography operation, etc. In the field of electrophotography and

  electrostatic recording, charging devices

  geometry and discharge using the corona effect or ef-

  Electrical fluids are known and widely used, devices in which a high voltage is applied to a thin wire of 0.1 mm in diameter, for example, for

  produce a discharge of corona. However, these provisions

  have the disadvantage that the wire can be easily

  broken because of its fineness. Moreover, the thread is easy-

  fouled or dusty, resulting in uneven production of odor and thus a

  a non-uniform discharge of an element to be loaded or

  ger. In addition, a shield or conductive shield surrounding the corona wire must be spaced a distance apart, so that the reduction in the size of the device

is limited.

  Another type of discharge device has been proposed, as described in US Pat. No. 4,155,093, in which the dielectric element is mounted.

  between two electrodes. By applying an alternating voltage

  Between the electrodes, positive and negative ions are produced at the junction between the dielectric element and one of the electrodes. Among these ions, those of a polarity

  are extracted by an external electric field.

  This type of discharge device is advantageous

  This can significantly reduce its size in reali-

  the dielectric element to a small thickness (not

  not more than 500 μm, and preferably from 20 to 200 μm).

  The invention is intended to provide a

  addition to the discharge device of this type. The main subject of the invention is a method and a device by means of which an element to be charged or discharged is subjected to increasing charging or discharging power in order to avoid a sudden charge operation. The invention also relates to a method and a device by means of which an element to be loaded

  or to discharge the east substantially uniformly.

  The invention also relates to a device of small size and by means of which an element to be loaded

  or unload the east substantially uniformly.

  Another object of the invention resides in a

  positive having a high efficiency of charge or

  discharge with a source of energy supply

relatively low

  The invention also relates to a method and a device whose operation is stable, in spite of

  variations in ambient conditions such as weather

  temperature and humidity, and by means of which the element

  load or unload the east with satisfactory uniformity

health.

  In accordance with one embodiment of the invention,

  a device for charging or discharging an element, which device comprises a dielectric element, an inductive electrode and an electrode.

  mounted on opposite sides of the dielectric element

  electric power source, and a source of energy supply

  to apply an alternating voltage between the inductive electrode and the discharge electrode to produce a

  superficial discharge on a surface of the di-

  on the side of this element presenting the electro-

  discharge, the charge density of the discharge area

  superficial being modified in the direction of the

  of the discharge electrode so that it is possible to

  to avoid a sudden load operation.

  The invention will be described in more detail with reference to the accompanying drawings by way of non-limiting examples and in which: FIG. 1 is a diagrammatic view of a first

  embodiment of the discharge device according to the

prevention:

  FIG. 2 is a perspective view of an elementary

  discharge device used with the device shown in FIG. 1;

  FIG. 3A shows a state of super-discharge

  perfective obtained when the present invention is not used;

  FIG. 3B represents a super-discharge state

  perfective obtained with the method and the charging device or discharge according to the invention;

  FIG. 3C represents a super-discharge state

  perfective obtained using the method and'de device according to the invention;

  - Figure 4 is a graph showing a relationship

  between the peak-to-peak alternating voltage and the

  of the surface discharge zone formed on the

  positive discharge at which this voltage is applied; FIG. 5 is a schematic view of another

  embodiment of the discharge device according to the

vention;

  FIG. 6A is a perspective view of a

  discharge device used with the device shown in FIG. 5; Figs. 6B, 6C and 6D are plan views showing examples of several rows of electrically connected discharge electrodes;

  FIG. 7A shows a state of super-discharge

  perfective obtained with the device shown in Figures 5 and 6;

  FIG. 7B represents a state of discharge-su-

  perfected that the discharge is not sufficient;

  FIG. 7C represents another super-discharge state

  perfective obtained using the device according to the invention; and - Figure 8 is an elevation of another form

embodiment of the invention.

  FIG. 1 represents a discharge device according to the invention, which comprises a discharge element 1 opposed to an element 2 to be loaded or unloaded (called more

  simply below item to load). The element l of de-

  charge comprises a dielectric element 3, an inductive electrode 4 and a discharge electrode 5. Figure 2

  is a perspective view of the discharge element 1.

  The discharge electrode 5 is a simple linear elongate member arranged to extend parallel to the center

of the inductive electrode 4.

  An alternating voltage is applied by a

  this 6 of alternating voltage between the inductive electrode 4 and the discharge electrode 5. Moreover, the element 2 to be loaded, which is moved in the direction indicated by the arrow

  A with respect to the discharge device 1, includes an em-

  conductive base 2a and an insulating or photoconductive element

  2b. A bias voltage is applied by a

  source 7 of polarization voltage between the

  duct 2a and the discharge electrode 5.

  In operation, when the alternating voltage is applied between the inductive electrode 4 and the discharge electrode, an electric discharge occurs at close proximity.

  immediate contact with the electrode 5 so as to generate sufficient

  of positive and negative ions. Because of the application

  the bias voltage between the discharge electrode 5 and the conductive base 2a of the element 2, the positive or negative ions are selectively extracted and directed towards the surface of the insulating or photoconductive layer 2b of the element 2 to load it to a desired level,

at the chosen polarity.

  As regards the material of the dielectric element

  a relatively high hardness material, for example

  ceramic, mica, glass or other, or a

  flexible organic high polymer, such as a poly-

  imide, ethylene tetrafluoride, polyester,

  acrylic, vinyl chloride, polyethylene

other, can be used.

  FIGS. 3A and 3B show surface discharge states at the discharge electrode 5, such as

  seen from the side of the discharge electrode, when

  that an alternating voltage is applied between the inductive electrode 4 and the discharge electrode 5 of the device 1 shown in FIGS. 1 and 2.

  of inductor 4 is in contact with the rear face of the

  the dielectric element 3, as shown in phantom.

  The width is indicated by the letter L. The hatched area

  is the area in which the superficial discharge is

  along the surface of the dielectric element 3, on

  both sides of the discharge electrode 5.

  Figure 3A shows the state of the surface discharge.

  when the present invention is not used. The

  superficial discharge zone 10 extends on both sides of the

  of the discharge electrode 5 and its width 1 is not

  not regular over the length of the discharge electrode 5.

  Therefore, when the element 2 to be charged is opposed to the discharge electrode 5 and is displaced with respect thereto

  as shown in FIG. 1 in order to charge the insulating layer

  or photoconductive 2a, its surface is not uniform.

  loaded, that is, the distribution of potential

  surface is not uniform in the longitudinal direction

  tudinal, because of the lack of uniformity previously described

is lying.

  It appeared that the width t of the zone 10 of

  surface charge changes with the peak-to-peak value of

  the alternating voltage applied between the inductive electrode

  this 4 and the discharge electrode 5.

  The graph in Figure 4 illustrates this, namely

  the peak-to-peak value of the voltage, in abscissa

  the width of the superficial discharge zone 10, the ordinate The superficial discharge begins at a point

  B. With the increase in the peak-to-peak value, the

  the area of superficial discharge increases and

  finally dyes a state of saturation. When she is

  the width of the superficial discharge zone is substantially equal to the width L of the inductive electrode 4, that is to say that the superficial discharge zone

  extends substantially to the side or end edges

  lateral temples of the inductive electrode 4. It does not extend

  not beyond the side edges, even if the peak-to-peak value

  crest is further increased. The dielectric element 3 used consisted of an alumina ceramic having a

  thickness of 200 μm, and the discharge electrode 5 and the

  inductive electrode 4 had a width of 500 Jm and

6.5 mm, respectively.

  The present invention uses this to produce a substantially uniform charge of the element 2 to be charged,

  the entire length of the discharge device 1, independently

  lack of uniformity of the material of the element

  dielectric 3 and / or scratches of the electrodes and the like.

  Figure 3B illustrates the present invention. com-

  I depicted, the discharge electrode 5 is parallel to the central axis of the inductive electrode 4, but is shifted towards one of the lateral edges of this electrode 4 (towards the

  top edge, in this figure). Therefore, the electro-

  5 of discharge is at a smaller distance from one of the lateral edges of the inductive electrode 4 than the other edge (the lower edge) .Because of this offset,

  the upper limit 12 of the zone 10 of superficial discharge

  is closer to the upper lateral edge of the inductive electrode 4, but saturates at the edge

  side and does not extend beyond that edge.

  As will be apparent from the explanation given with reference to FIG. 4, the upper limit of the surface discharge zone 10 is substantially rectilinear over the entire length of the discharge element 1 and the density of the ions in the upper part of the superficial discharge zone is uniform over its length. The lower limit of the surface discharge zone 10 remains non-uniform. However, by moving the element 2 under the discharge element 1 as shown in FIG.

  the direction indicated by the arrow so that element 2 is from

  edge exposed to the ions of the lower part (Figure 3B) and those of the upper part of the discharge zone, the influence of the lack of uniformity of the lower part is reduced by the uniform discharge zone of the upper part, so that a substantially uniform load can be realized.This arrangement corresponds to an offset

  of the discharge electrode 5 to the right in the direction of

  FIG. 1, from the center of the electrode

driver 4.

  Another important benefit will now be explained.

  than. When the discharge electrode 5 is moved as shown in Fig. 3B, for example, the upper surface discharge area has a higher charge density than the lower area. Therefore,

  when item 2 is moved in the direction indicated below

  above, it is subjected, during the first half of its displacement, to a relatively weak load operation, then it is subjected, during the second half, to a relatively powerful load operation, by the part

  of the charge-density surface discharge zone

  raised, the element 2 is thus loaded to the desired level.

  A photosensitive element, for example, must not

  be loaded sharply to a high level because its

  In this way, the life expectancy is reduced or stings can be formed. This is well known. The invention is very advantageous in such a use, since the first half of the charging operation is carried out under the relatively low charging power and the second half can be conducted at a sufficiently high power to charge the element until at the desired level, in a period of

limited time.

  It has been found that the lower limit 13 of the surface discharge zone 10 can be extended to the lower side edge of the inductive electrode 4 by

  elevation of the peak-to-peak value of the alternating voltage

  applied between the inductive electrode 4 and the electro-

  of 5 discharge. With the increase in the peak-to-value

  peak, the lower limit 13 of the superficial discharge zone widens towards the lower lateral edge of

  the inductive electrode 4 and finally reaches saturation.

  The lower limit 13, when saturated, reaches

  substantially the lower side edge of the electrode

  duct 4. It does not extend beyond this side edge,

  even if the peak-to-peak value is further increased.

  The present invention uses this phenomenon to make

  shape the width of the superficial discharge area on

  the entire length of the discharge device 1, independently

  lack of uniformity in the material of the di-

  3 and / or the presence of scratches on the electri-

  trodes and others. In addition, it is possible to avoid the

sudden or sudden charges.

  FIG. 3C shows the surface discharge 10 obtained with the discharge device according to the invention which uses this phenomenon. The peak-to-peak value of the AC voltage is chosen so as to extend the two lateral edges of the superficial discharge zone.

  substantially to the respective lateral edges of the

  the inductive electrode 4, over the entire length of the discharge device 1. Thus, as shown in FIG. 3C, the

  width of the surface discharge zone 10 is sensi-

  the width of the inductive electrode 4 and is therefore uniform. Since the applied voltage is an alternating voltage, the width, in the very strict sense, changes at a high frequency, but the maximum width is substantially equal to the width of the inductive electrode 4

and is therefore uniform.

  When item 2 to be loaded is subject to the

  As shown in FIG. 1, with the aid of the discharge device described above, this element 2 is furthermore uniformly charged. As described

  previously, the area 10-of superficial discharge

  does not extend beyond the width L of the inductive electrode 4, even if the voltage is increased. The only variation is

  the increase of the charge density of the zone 10 of

  superficial load. The charge densities in the parts

  upper and lower part of the

  are respectively uniform in the long-term direction

  gitudinale. Since the charge density is more

  large in the upper part of the overflow zone.

  perfective than in the lower part, it is possible to avoid a sudden charge application, as in the case of the

  embodiment of Figure 3B.

  By using this phenomenon as much as possible, we can

  load in a relatively stable manner despite

  variations in ambient conditions, which makes it possible

kill a satisfying charge.

  As previously described, in accordance with the invention

  the small size discharge device. is

  the lack of uniformity of the char-

  ge. In addition, the element to be loaded or unloaded can first be subjected to a weak action, then to an action whose strength can rise to a desired level, without

  that it is necessary to use special means of

  mande. The alumina ceramic dielectric element 3, having a thickness of 200 Am, is mounted between the discharge electrode with a width of 500 Nm and the inductive electrode 4 with a width of 4 mm. The discharge electrode 5

  is shifted 1 mm towards one of the lateral edges (upper edge

  3B) of the inductive electrode 4, from its center. An alternating voltage of a peak-to-peak value of 2 kV is applied between the discharge electrode 5 and the inductive electrode 4. The superficial discharge zone does not extend to the lateral edges of the electrode 4. When the element 2 to be charged is subjected to the discharge element 1, with a voltage of

  2 kV polarization applied by the polarization source 7

  tion, the lack of uniformity measured. on the surface of the

Element 2 is plus or minus 8%.

  Then, the peak-to-peak value of the AC voltage is raised to 3 kV in order to extend the upper edge of the surface discharge area substantially

  substantially reaches the upper lateral edge of the electro-

  4. Therefore, the upper limit of 12

  the surface discharge zone 10a is substantially recessed

  tiligne along the element 1 discharge. In addition,

  ionity in this area is uniform over its length. However, because of the dimensional relationships described

  previously, the lower limit 13 of the zone 10d of

  superficial load is not uniform.

  It is preferred that the distances L1, L2 and L3 between the adjacent electrode members increase toward the lower portion of Fig. 7A, i.e. L1 <L2 <L3 ... Ln. It is furthermore advantageous that the distance

  LO between the upper lateral edge of the inductive electrode

  this and the highest electrode element 5a is less than half the distance L1 between the uppermost electrode element 5a and the adjacent electrode element 5b, and

  that the distance L4 between the lower lateral edge of the

  inductive electrode 4 and the discharge electrode element

  lowest age 5d is greater than half the distance

  this L3 between the lowest electrode element 5d and the element

  5c adjacent electrode, namely LO <(1/2) L1, and

L4> (1/2) L3.

  Since the distances between the adjacent electrode elements 5a, 5b, 5c and 5d are in the relationship

  described above, the lower limit of the area of de-

  surface charge 10a is partially in contact or

  superposition with the upper part of the

  superficial charge from the electrode element of

  discharge 5b. However, these areas are spaced apart,

  parties, so that they are not globally

  forms. Between the electrode elements 5b and 5c and between

  electrode elements 5c and 5d, the super-discharge zones

  are more distant. However, the limit

  12 of the superficial discharge zone 10a

  appreciably with the upper side edge of the elec-

  inductive trode 4 and is substantially rectilinear, and the density of the ions is uniform over the length of the element to the upper lateral edge of the inductive electrode

  4, and charging is carried out under the same conditions.

  The measured inconsistency is plus or minus 4.5%.

  The peak-to-peak value of the AC voltage is then raised to 5 kV to extend both side edges.

  from the superficial discharge zone to the lateral

respective walls of the inductive electrode, over the entire length. The lack of uniformity measured is over or

minus 3%.

  According to the invention, the lack of uniformity

  the load can be reduced, as described above, and

  moreover, a sudden load application can be avoided.

  Figures 5 and 6A show another form

  realization of the discharge device according to the invention.

  Figure 6A is a perspective view of the discharge member 1. Since this element is similar to the embodiment described with reference to FIGS. 1 and 2,

  except for the discharge electrode which consists of several

  if rows of discharge electrode elements,

  intervals, as described in more detail below,

  and the width of the inductive electrode 4 which is aucmen-

  corresponding parts, similar parts do not

  will not be described again in detail, for more

  the elements whose functions correspond to that

  the elements described previously bearing the same

numerical references.

  Fig. 7A shows an embodiment with four discharge electrode elements 5a, 5b, 5c and d. The highest element 5a of discharge electrode and

  the lowest element 5d discharge electrode are dis-

  placed so that the distance L0 between the highest element 5a and the upper lateral edge of the inductive electrode 4 is less than the distance L4 between

  the lowest element 5d and the lower edge of the electro-

of inductor 4.

  The upper limit 12 of the surface discharge zone 10a of the highest electrode element 5a of unloading, so that, if the element 2 to be loaded is affixed to the discharge element 1 and is displaced relative to

  to it so that it is first subject to the area of de-

  lower surface charge 10Od of the element 1 of

  charge, then to the upper superficial discharge areas

  fct, 10b and 10a, in this order, the influence of the lack of

  The density of the surface discharge zones is eliminated by this final zone 10a of superficial discharge,

  so that a substantially uniform load is obtained.

  As in the previous embodiment

  - you ,. the charge density in the super discharge zonelOa

  ficialIt is larger than in the lower zones of

  superficial discharge, this density decreasing progressively

  towards the lower part of the figure. Therefore,

  when the element 2 to be loaded is moved in the indi-

  previously, it is first subject to a relative charge

  Low charge density with lower charge density, and charging power gradually increases until the cell is charged to a level. desired by the surface charge area having the highest charge density.

  As previously described, this is especially

  advantageously in electrophotography or other.

  The various rows of electrode elements may be electrically connected in the manner of a comb as shown in Fig. 6B, by opposite ends as shown in Fig. 6C, or zig-zag as shown.

in Figure 6D.

  When several electrode elements are used

  the intervals between the adjoining electrode elements

  are preferably monotonically reduced as previously described. However, when their numbers are large, it is not necessary for the intervals to decrease

  monotonically in the strict sense, provided they are globally

decrease.

  By raising the peak-to-peak value of the AC voltage applied between the inductive electrode 4 and

  the discharge electrode 5, the width of the zone is increased.

  no superficial discharges from each of the elements of

  the discharge electrode, until the superficial discharges occur over the entire width of the inductive electrode 4. Figure 7B shows such a state. In this form

  the peak-to-peak value of the alternating voltage

  native is such that both sides of the overburden

  The electrodes coincide substantially with the respective lateral edges of the inductive electrode 4 and the surface discharge has no gaps between the electrode elements 5a, 5b, 5c and 5d. As shown, both

  lateral edges of the entire super-discharge zone

  ficielle extend substantially to the side edges

  of the inductive electrode 4 so that the

  no superficial discharge is totally uniform in

the longitudinal direction.

  When item 2 to be loaded is subject to the

  charge in the manner described with respect to the

  Figure 1, using the device described previously

  This element 2 is loaded more uniformly. As previously described, the superficial discharge zone does not

  not extend beyond the width L of the inductive electrode

  trice 4, even when the voltage is increased. The only variation is an increase in the density of

  charge of the superficial discharge zone 10. The density.

  charge is uniform over the entire length of the discharge member 1, at a given position of the width. In addition, the charge density increases progressively from one side edge to the other, so that it is advantageous in the case of use in electrophotography, because

  it makes it possible to avoid a brutal charge operation, com-

this is the case of Figure 3B.

  By using this phenomenon as much as possible, we can

  load in a relatively stable manner despite

  variations in ambient conditions, which makes it possible

make a satisfactory charge.

  When the discharge electrode is constituted

  of a single element, the width of the super-

  ficiellt is determined by the peak-to-peak value of the

  AC voltage. Therefore, to increase the

  of the area of superficial discharge, it is necessary

  to raise the tension in a relatively important way.

  However, when several electrode elements are u-

  the width can be increased without the need to raise the tension to such a degree. The width can be increased as desired by increasing the

  number of electrode elements, which improves remarkably

  the efficiency of the charge or discharge. In addition, by changing the intervals between the electrode elements, the density distribution can be modified.

charge.

  Figure 7C illustrates the state of a super discharge.

  different from those previously described. In this figure, the surface discharge areas 10a, 10b, c and 10d depart from the respective discharge electrode elements 5a, 5b, 5c and 5d and the width of each of them is not uniform over their length. Thus, if the element 2 to be loaded is moved as shown in FIG. 1 so that the surface of the insulating or photoconductive layer 2b is charged, the distribution of the resulting charge is not uniform over the length of the element 1 discharge,

as in Figure 3A.

  The dielectric element 3 made of alumina ceramic,

  200 dm thick, is clamped between the internal electrode

  duct 4, with a width of 16 mm, and four elements of

  discharge electrode 5a, 5b, 5c and 5d spaced 1mm (L0), 3mm (L1), 4mm (L2), 5mm (L3) and 3mm (L4), respectively,

  and each having a width of 500 Dm. Alternate voltage

  a peak-to-peak value of 2 kV is applied between

  the discharge electrode elements and the inductive electrode

  4. The surface discharge zone does not extend

  to the lateral edges of the inductive electrode 4,

  me in Figure 7C. When the element 2 to be loaded is

  subject to the discharge element 1, with a voltage of

  2 kV applied by the polarization source 7

  tion, we measure a lack of uniformity more or less

  7.5% on the surface of element 2.

  The AC voltage is then increased to bring it to 3 kV, peak-to-peak, to extend at least

  the surface discharge zone 10a of the elec-

  upper trode 5a substantially to the upper lateral edge

  of the inductive electrode 4, and charging is carried out under the same conditions. The lack of uniformity

  measured is plus or minus 4%. In addition, the voltage

  ternative is raised to 5 kV, peak-to-peak, to extend

  areas of superficial discharge so that they

  the entire surface corresponding to the inductive electrode

  4. Uniformity measured is plus or minus 2.5%. According to the invention, the lack of uniformity of the charge can be reduced as described above and, from

  moreover, one can avoid a sudden charge application.

  As another variant for gradually increasing the load power, it is possible to modify the thickness of the dielectric element 3 in the direction

  In this structure, the electric field

  Turning the discharge electrode 5 is stronger as the thickness of the dielectric member 3 decreases and the surface discharge area extends further toward the side of the thin dielectric member. The discharge electrode 5 may consist of several rows of discharge electrode elements. In this embodiment, the thickness-varies

  continuously, but can be edited in steps.

  As a variant, when a plurality of electro

  of discharge are used, the tension applied to them

  can be modified gradually.

  As previously described, in accordance with the invention

  the element to be charged or discharged can first be loaded under a low load power, then loaded with increasing load power, without the need for special control means and,

  moreover, a substantially uniform charge can be

  in the small size discharge device.

  In each of the embodiments described above, the width i of the surface discharge zone depends on the material, the dielectric constant

  and the surface resistivity of the dielectric element

  3, but the specialist can determine the value

  peak-to-peak depending on these factors, without difficulty.

  In addition, the width varies according to the conditions

  ambient conditions such as atmospheric pressure, temperature, humidity and degree of soiling

  surface of the dielectric element 3. The peak-to-peak

  peak can be determined, based on the actual conditions in which the device is used, so

  that the area of superficial discharge extends sensitively

  to the side edges of the inductive electrode

  4, and such a determination is desirable.

  AC voltage is not limited to one

  alternating voltage, and it can be

  ter in the form of rectangular waves or a voltage

pulsed alternative.

  The above description focused on the applica-

  charge to an element. When the discharge device is closer to the element, the element can be discharged, i.e. an electric charge can be removed. In this case, the voltage source 7 is

  not necessary. The invention as described is used

  ble, with its advantages, also in this case.

  The voltage source 7, when used, can provide a DC voltage or pulsed voltage if the ions produced near the discharge electrode 5

  may be directed to the item to be loaded or unloaded

ger.

  It goes without saying that many modifications can

  can be made to the described process and device

  represented without going beyond the scope of the invention.

Claims (9)

  1. A method for loading or unloading an element, characterized in that it consists in opposing an element (2),   on which to act, a discharge element (1)   a dielectric element (3), an inductive electrode (4) and a discharge electrode (5) mounted on opposite sides of the dielectric element so that the electrode   discharge is directed towards the element on which we owe   to apply an alternating voltage between the inductive electrode and the discharge electrode in order to produce a   superficial discharge on a surface of the dielectric element   on the face of the latter bearing the discharge electrode, the charge density of the discharge zone (10)   superficial being modified in the direction of the   discharge element, and to move the element to be acted upon with respect to the discharge electrode so that it is subjected to a low charge density portion and then to a high density portion of the discharge electrode. charge for this element to be charged or discharged by the discharge superficial thus produced.   2. A method of charging or discharging an element, characterized in that it consists in opposing, to an element (2) on which one must act, a discharge element (1).   having a dielectric element (3), an electrode   conductor (4) and a discharge electrode (5) mounted on opposite sides of the dielectric element so that the discharge electrode is facing the element   on which to act, to apply an alternating voltage   between the inductive electrode and the discharge electrode to produce, on a surface of the dielectric element, a surface discharge located on the face of the dielectric element carrying the discharge electrode, a part of the zone (10 ) a surface discharge located on a first side of the discharge electrode having a lower charge density. to that of a portion of the surface discharge zone on the other side of this electrode, and to move the element on which to act relative to the discharge electrode, the first side   to the other side, in order to load or   with the help of the surface discharge thus produced.   3. Method for loading or unloading an element, characterized in that it consists in opposing an element (2)   on which to act, a discharge element (1)   a dielectric element (3), an inductive electrode (4) and a discharge electrode (5) mounted on the opposite sides of the dielectric element so that the discharge electrode faces the element on which it is to be   act, to apply an alternating voltage between the electro-   of inductor and the discharge electrode to produce a   superficial discharge on a surface of the dielectric element   with the discharge electrode, one of the   lateral surfaces of the surface discharge zone (10) coinciding substantially with one of the lateral edges of the inductive electrode, and moving the element on which to act relative to the discharge electrode in order to charge or discharge this element using the dump superficial thus produced.   4. A method of charging or discharging an element, characterized in that it consists in opposing, to an element (2) on which one must act, a discharge element (1).   having a dielectric element (3), an electrode   duct (4) and a discharge electrode (5) mounted on   opposite sides of the dielectric element so that the   the discharge electrode is turned towards the element on which   must act, the discharge electrode extending over a   side of the dielectric element, parallel to the central axis   tral of the inductive electrode, in a position such that   the discharge electrode is further away from an edge   side of the inductive electrode than the other side edge   of this inductive electrode, the method also comprising   to apply an alternating voltage between the electrode   inductor and the discharge electrode to produce a   surface charge on a surface of the dielectric element   carrying the discharge electrode, one of the edges   side of the zone (10) of superficial discharge   substantially with the first mentioned side edge of the inductive electrode, the method further comprising moving the element to be actuated relative to the discharge electrode to charge or discharge this   element by means of the superficial discharge thus produced   you. 5. Device for loading or unloading an element   (2), characterized in that it comprises a dielectric element   that (3), an inductive electrode (4) and a discharge electrode (5) mounted on the opposite sides of the dielectric element, and a source (6) of power supply   intended to apply an alternating voltage between   inductive trode and discharge electrode in order to produce   a surface discharge on a surface of the di-   electrode carrying the discharge electrode, the charge density of the variant surface discharge zone (10)   in the direction of the width of the discharge electrode.   6. Device for loading or unloading an element   (2), characterized in that it comprises a dielectric element   that (3), an inductive electrode (4) and an electrode (5)   mounted on opposite sides of the dielectric element   and a source (6) for supplying energy from   to apply an alternating voltage between the electrode   inductor and the discharge electrode to produce a   surface charge on a surface of the dielectric element   carrying the discharge electrode so that one   part of the area (10) of superficial discharge located on a   first side of the discharge electrode has a density   lower than that of part of the   superficial discharge located on the other side of this elec-   trode. 7. Device for loading or unloading an element   (2), characterized in that it comprises a dielectric element   that (3), an inductive electrode (4) and an electrode (5)   mounted on opposite sides of the dielectric element   the discharge electrode extending on a surface of the dielectric element, along the central axis of the   inductive electrode, in a position such that the elec-   discharge trode is further removed from a first   side of the inductive electrode than on the other side   ral of this electrode, the device also comprising   a source (6) of power supply for application   connect an alternating voltage between the inductive electrode and   the discharge electrode to produce a super discharge   on a surface of the dielectric element carrying the discharge electrode, one of the lateral edges of the zone   superficial discharge coinciding substantially with the-   said first side edge of the inductive electrode.   8. Device according to claim 7, characterized   in that the discharge electrode comprises a plurality of   of discharge electrode elements (5a, 5b, 5c, 5d)   andwherein the distance between one of the   of the dielectric element and the row of discharge electrode elements closest to said first lateral edge is less than the distance between the other side edge of the dielectric element and the row of   discharge electrode elements closest to said side edge.   9. Device according to claim 8, characterized   in that the distances between the adjacent rows   electrode elements decrease in the direction of said first side edge.