Ionization apparatus

Description

[0001] The invention is directed to a ionization apparatus according to the general part of claim 1 and to a method for detecting an indication for surface housing pollution on the housing surface of an ionization apparatus according to the general part of claim 12.

[0002] The ionization apparatus in question has its application in controlling the charge of a target area. In particular, this includes the neutralization of a target area which is often required when plastic films are being processed in the bag-making industry or the like.

[0003] A known ionization apparatus (EP 2 061 124 A2), which is to be considered the starting point of the invention, comprises a high voltage power supply arrangement with a ion emitting electrode connected thereto. The voltage power supply arrangement supplies a bipolar voltage against ground potential to a so called ionizer bar. Such a ionizer bar normally comprises a number of ion emitting electrodes that are supplied with the voltage of the high voltage power supply arrangement.

[0004] Prior art document EP 0 850 759 A1 disclsoes an electrostatic assist system which possesses an electrode contamination detecting circuit for detecting surface leakage current that flows between the static electrode of a charge unit and a contamination detecting device and a warning device for warning when the surface leakage current is out of a safety range.

[0005] One problem of the ionization apparatus in question is the fact that the ionizer bar may not be focused exactly onto the target area, for example the plastic film to be processed. This is why dust particles as well as housing components of the ionization apparatus are being charged or at least being influenced by the ionizer bar as well. In the end a considerable amount of dust and dust-like particles are being attracted to various housing parts such that housing surface pollution is building up during operation.

[0006] The above noted housing surface pollution may, depending on its composition, provide a layer of conducting material on the housing surface which can lead to decrease in performance or even a shortcut situation.

[0007] The problem underlying the invention is to improve the known ionization apparatus such that the buildup of housing surface pollution can be detected in a reproducible manner.

[0008] The above noted problem is solved by a ionization apparatus according to the characterizing part of claim 1.

[0009] The proposed solution is based on the finding that the electrical properties of housing surface pollution may be used for an easy detection of the buildup of such housing surface pollution.

[0010] In detail a measuring arrangement with at least one measuring electrode connected thereto is provided for detecting an indication for housing surface pollution, which detecting is based on a change in complex resistance between at least one said ion emitting electrode and at least one said measuring electrode.

[0011] The at least one ion emitting electrode is coupled to ground potential via a complex resistance that depending on the installation may be composed of a large number of ohmic devices, capacitive devices and, if so, even inductive devices. What is important for the present invention is the fact that at least a part of the complex resistance between ion emitting electrode and the measuring electrode is influenced by housing surface pollution as long as the measuring electrode is positioned correctly.

[0012] The positioning of the measuring electrode is correct in the above noted sense if the buildup of housing surface pollution leads to a change in voltage measured at the measuring electrode against ground. In this situation the complex resistance between the ion emitting electrode and ground may be seen as two complex resistances that are serially coupled. In this sense one complex resistance corresponds to the path between the ion emitting electrode and the measuring electrode and the other complex resistance corresponds to the path between the measuring electrode and the ground potential.

[0013] The proposed measurement only works with AC-voltages and AC-currents as the measurement is based on the change of complex resistances due to the buildup of housing surface pollution. Accordingly, for performing measuring cycles by the measuring arrangement an AC-voltage at the ion emitting electrode is necessary. The expression "AC-voltage" is to be widely understood. For example, it includes a pulsed DC-voltage as will be explained further down.

[0014] In the preferred embodiments according to claims 2 to 5 such an AC-voltage is provided anyhow for the ionization process. In the further preferred embodiment according to claim 6 it is proposed to evaluate the voltage against ground at at least one said measuring electrode during ionization. Accordingly the voltage which is supplied to at least one said ion emitting electrode is being used not only for ionization but also for detecting an indication for housing surface pollution by the measuring arrangement. This leads to a cost saving apparatus altogether.

[0015] According to the proposal it has been found that for particularly good measurement results at least one said ion emitting electrode and at least one said measuring electrode are to be located on opposite sides of a housing wall which surface pollution is to be detected. This has been proven successful especially when the respective housing wall is made of a plastic material.

[0016] According to claim 11 the housing comprises at least one rib like wall segment that mechanically protects the at least one ion emitting electrode which protrude from a housing wall and that the at least one rib like wall segment is detachably connected to the rest of the housing. This rib like wall segment is preferably connected to the rest of the housing via a snap fit connection.

[0017] According to claim 11 it has been found that in some areas of operation it is more efficient to exchange certain housing components instead of cleaning them after having detected the buildup of housing surface pollution. In order to make this possible it is proposed to have the above noted rib like wall segments connected detachably to the housing, preferably via a snap fit connection as noted above.

[0018] The idea described above with respect to claim 11 is to be considered a teaching which does not necessarily require the above noted measuring arrangement. Therefore a ionization apparatus comprising a housing and at least partly within the housing a high voltage power supply arrangement with a ion emitting electrode connected thereto, wherein the housing comprises at least one rib like wall segment that mechanically protects the ion emitting electrodes protruding from a housing wall and that the at least one rib like wall segment is detachably connected to the rest of the housing, preferably, wherein the rib like wall segment is connected to the rest of the housing via a snap fit connection, shall be claimable as such as well.

[0019] According to the teaching of claim 12 a method for detecting the above noted indication for surface housing pollution on the housing surface of an ionization apparatus is claimed independently.

[0020] According to the method it is proposed that an above noted measuring arrangement with at least one measuring electrode connected thereto is provided and that an indication for housing surface pollution is being detected by the measuring arrangement based on a change in complex resistance between at least one said ion emitting electrode and at least one said measuring electrode.

[0021] The method according to claim 12 is directed to the operation of the ionization apparatus according to claim 1. All explanations and advantageous variants explained with reference to claim 1 are fully applicable to the teaching of claim 12.

[0022] In the following the invention is explained referring to only one embodiment shown in the drawings. The drawings show in

Fig. 1

a ionization apparatus according to the invention in a perspective view,

Fig. 2

the ionization apparatus according to Fig. 1 in a sectional view along the line II-II and

Fig. 3

a schematical circuit diagram with only those components of the ionization apparatus that are relevant for the present invention.

[0023] The ionization apparatus shown in Fig. 1 may be applied in various areas as explained in the general part of the specification. The main area of application for the displayed ionization apparatus is the neutralization which is not to be understood as a restriction.

[0024] The ionization apparatus comprises a housing 1. The expression "housing" is to be understood in a broad sense. Accordingly the housing includes all components that are depicted with reference numbers 1a, 1b, 1c and Id, 1e and 1f. Those components 1a-f will be explained in detail later on.

[0025] At least partly within the housing 1 a high voltage power supply arrangement 2 with at least one ion emitting electrode 3-5 is provided. In the preferred embodiment altogether three ion emitting electrodes 3-5 are realized. Depending from the application more or fewer ion emitting electrodes 3-5 may be necessary.

[0026] It is of major importance for the proposed solution that a measuring arrangement 6 with at least one measuring electrode 7, 8 connected thereto is provided for detecting an indication for housing surface pollution based on a change in complex resistance Z' between at least one said ion emitting electrode 3-5 and at least one said measuring electrode 7, 8. For this measurement the at least one said ion emitting electrode 3-5 builds one common measurement port and the at least one said measuring electrode 7, 8 builds the other common measurement port.

[0027] It will be explained later that preferably a measuring electrode 7, 8 is assigned to a particular ion emitting electrode 3-5, such that the detection of the indication for housing surface pollution is based on a change in complex resistance Z' between the ion emitting electrode 3-5 and the measuring electrode 7, 8 assigned thereto.

[0028] The complex resistance Z' is shown in Fig. 2 in the sense of an equivalent circuit. As this is only the display of a theoretical approach to explain the real electric arrangement the complex resistance Z' is only displayed in dotted lines.

[0029] According to Fig. 2 between the ion emitting electrode 5 and ground potential 9 a complex resistance Z is present according to the equivalent circuit. The complex resistance Z is composed of a serious of the two complex resistances Z' and Z". According to this model the measuring electrode 8 is measuring exactly between the complex resistances Z' and Z".

[0030] Accordingly the complex resistance Z' describes the path between the ion emitting electrode 5 and the measuring electrode 8, comprising the sub-path between the ion emitting electrode 5 and the housing 1, which is mainly an air capacity and the path through the housing 1 itself. In addition the path between the ion emitting electrode 5 and the measuring electrode 8 may comprise a layer of housing surface pollution P which influences at least the value of the complex resistance Z'.

[0031] If now the housing surface pollution P is building up it is to be expected that due to the electric and ohmic effects the value of the complex resistance Z' will decrease. For the present evaluation only the value of the vectorial variable of the complex resistance is of interest such that the direction of the complex resistance will not be discussed at that point.

[0032] The above noted decrease of the value of the complex resistance Z' has the effect that the value of the voltage at the point between the two complex resistances Z', Z" against ground potential will increase, if the voltage supplied to the ion emitting electrode 5 against ground potential is kept constant. As noted above "voltage" in this respect is understood as an AC-voltage, as the underlying model is based on complex resistances.

[0033] It may be pointed out that the above noted model is applicable to all of the ion emitting electrodes 3-5 shown in the drawings. Just for an easy understanding the equivalent circuit comprising the complex resistances is only shown for the ion emitting electrode 5, which is assigned the measuring electrode 8.

[0034] Interesting now is the fact that the AC-voltage which is necessary for detecting the above noted indication for housing surface pollution is provided for ionization anyhow according to a preferred embodiment. Here, for ionization, the high voltage power supply arrangement 2 supplies high voltage with an AC-component to the ion emitting electrode 3-5 against ground. Preferably the high voltage power supply arrangement 2 in this respect supplies a modulated, further preferably a pulsed, DC-voltage to the ion emitting electrode 3-5 against ground. The supplied voltage is nothing else but a PWM-voltage with a certain duty-cycle.

[0035] The preferred value of the modulated, here and preferably pulsed, DC-voltage preferably lies between 2 kV and 60 kV, preferably between 20 kV and 40 kV. In addition or alternatively the pulse frequency lies between 0,5 Hz and 100 Hz, preferably between 1 Hz and 10 Hz.

[0036] It has been pointed out already that for the shown, preferred embodiment multiple ion emitting electrodes 3-5 are provided and that at least some of the ion emitting electrodes 3-5 are each assigned at least one said measuring electrode 7, 8, here and preferably exactly one measuring electrode 7, 8, for detecting an indication for housing surface pollution based on a change in complex resistance Z' between the respective ion emitting electrode 3, 5 and the respective measuring electrode 7, 8. As noted above, the measuring electrode 7 is assigned to the ion emitting electrode 3 and the measuring electrode 8 is assigned to the ion emitting electrode 5. Generally it can also be advantageous if at least some of the ion emitting electrodes 3-5 are as an electrode-group assigned to a measuring electrode 7, 8 or to multiple measuring electrodes 7, 8.

[0037] For ionization the high voltage power supply arrangement 2 supplies modulated, here and preferably pulsed, positive high DC-voltage to a first electrode-group of ion emitting electrodes 3, 4 against ground and modulated, preferably pulsed, negative high DC-voltage to a second electrode-group of ion emitting electrodes 5 against ground. The expression "electrode-group" is to be understood in a broad sense such that only one electrode can compose such an electrode-group. This is applicable for electrode 5 as noted above.

[0038] It is particularly important for the shown embodiment that the high voltage power supply arrangement 2 synchronizes the voltages supplied to the ion emitting electrodes 3, 4 and 5 such that during operation, in an alternating manner, the first electrode-group consisting of electrodes 3, 4 is supplied with a reference voltage and the second electrode-group consisting of electrode 5 is provided with high positive DC-voltage and then the first electrode-group consisting of electrodes 3, 4 is supplied with high negative DC-voltage and the second electrode-group consisting of electrode 5 is supplied with the reference voltage. Here and preferably, the supply with the reference voltage generally corresponds to the supply with ground potential. In another embodiment the reference voltage is a relatively low voltage against ground potential, for example a voltage in the area of 1 kV and 5 kV against ground potential.

[0039] The above noted high positive DC-voltage and high negative DC-voltage may be of the same value against ground potential. In another embodiment, however, those positive and negative voltages may be of different value against ground such that an unsymmetrically voltage supply will result.

[0040] The above noted alternating supply or DC-voltages leads to the situation that during the positive voltage pulse on the electrode 3, 4 the electrode 5 is supplied with ground potential and that during the negative pulse on the electrode 5 in turn the electrodes 3, 4 are supplied with ground potential. This leads to the fact that at all the times the full DC-voltage is present between the electrodes 3, 4 and the electrode 5. Only the polarity of the voltage periodically changes. With this arrangement, in an alternating manner, positive ions are being generated at the electrodes 3, 4 and negative ions are being generated at the electrode 5.

[0041] Is has been found in a particularly preferred embodiment that the above noted voltage supply at the electrodes 3-5 may be used for detecting an indication for housing surface pollution as noted above. In further detail it is provided that the measuring arrangement 6 evaluates the voltage against ground 9 at the measuring electrodes 7, 8 during ionization by the ion emitting electrodes 3-5. This leads to a very simple measuring arrangement as the measurement is reduced to detecting a voltage at the measuring electrode 7, 8 against ground 9.

[0042] In a cost effective embodiment a measurement arrangement 6 comprises a comparator unit 10 which compares the voltage against ground 9 at the measuring electrode 7, 8 to a threshold value V_ref and outputs a signal CLB (cleanbar) depending on the result of the comparison. If the voltage against ground at the measuring electrode exceeds the threshold value V_ref the output signal CLB is set to a high level. If the voltage against ground at the measuring electrode 7, 8 stays below the threshold value the output signal CLB is set to a low level. The comparator unit 10 may be an electronic part like an operational amplifier, a microcontroller or the like.

[0043] The value of the above noted voltage at the measuring electrode 7, 8 may also be transferred to other components via a serial data interface and/or a data bus system. For this, preferably, a analog/digital conversion is being performed on the measured voltage.

[0044] In order to reduce the influence of one electrode-group on the other electrode group during detection an indication for housing surface pollution in the above noted sense a rectifier 11 is preferably provided between the measuring electrode 7, 8 and the comparator unit 10. This rectifier 11 in this sense is designed to pass through only the positive half-waves for the electrodes 3, 4 and the negative half-waves for the electrode 5.

[0045] Further preferably, between the measuring electrode 7, 8 and the comparator unit 10 at least one filter, preferably a low-pass filter 12, is provided for smoothening out the measured signal.

[0046] As shown in Fig. 2 the measuring electrodes 7, 8 are provided in addition to the ion emitting electrodes 3-5. This makes the electric circuit of the measuring arrangement 6 simple and cost efficient. However, it may be advantageous to use at least one ion emitting electrode 3-5 as a measuring electrode. This can reduce the complexity on the side of the measuring electrode.

[0047] It has been pointed out already that the optimal location of the measuring electrodes 7, 8 is essential for the proposed solution. Here the ion emitting electrodes 3-5 and the measuring electrodes 7, 8 are located on opposite sides of a housing wall 13 which surface pollution is to be detected. Here it becomes clear that the expression "housing wall" is to be understood in a broad sense. For example, according to Fig. 2 the housing wall 13 is at least a double wall consisting of housing components 1a, 1b and 1d. All of those housing components are here and preferably non-conductive components. The housing components 1a and 1d are made of plastics, in particular PVC, while housing component 1b is a casting resin.

[0048] Further preferably it is proposed that the ion emitting electrode 3-5 and the measuring electrode 7, 8 assigned to the respective ion emitting electrode 3-5 are located offset from one another along the housing wall 13, 14 which surface pollution is to be detected. The above noted offset is indicated in Fig. 1 with the reference number 15.

[0049] As noted above the housing wall 13, 14 which surface pollution is to be detected is made of a plastic material, preferably of PVC. It is generally possible, however, that for such housing walls 13, 14 coated metal or the like is being used.

[0050] Fig. 2 shows that the measuring electrode 7, 8 is located close to the respective side of the housing wall 13, 14 which surface pollution is to be detected. In the shown embodiment according to Fig. 2 the measuring electrode 7, 8 is even in contact to the respective side of the housing wall 13, 14, here to the lower side of the respective housing wall 13, 14. In order to guarantee the contact it is further preferably so, that the measuring electrode 7, 8 is spring tensioned against the respective side of the housing wall 13, 14. Accordingly a spring is coupled to the measuring electrode 7, 8 as is shown in Fig. 2 as well.

[0051] The measuring electrode 7, 8 is preferably of spherical design. With this it is possible to provide a punctual contact to the respective housing wall 13, 14 such that this contact in electrical terms, in particular in view of the capacity between the measuring electrode 7, 8 and the respective housing wall 13, 14, stays exactly constant even if a certain deformation of the housing 1 due to temperature changes occur.

[0052] The structure of the housing 1 is simple for the shown embodiment. The housing 1 comprises the housing component 1a which carries the ion emitting electrodes 3-5 as well as a PCB 16 for the high voltage power supply arrangement 2 as well as for the measuring arrangement 6. On the upper side of this housing component 1a the electrodes 3-5 together with electrode resistances and the like are being embedded in a casting resin, depicted with reference number 1b.

[0053] The measuring electrodes 7, 8 are fixed on the PCB 16 and press against the lower side of the housing component 1a. The housing 1a is closed to the bottom side by the housing component 1c which may be of plastics material as well or of metal material.

[0054] The ion emitting electrodes 3-5 are constructed in an interesting manner, as may be seen from Fig. 2. The electrodes 3-5 comprise a non conducting sheathing 3a, 5a which may be exchanged if the surface pollution on the sheathing 3a, 5a has built up to a certain level. The exchange may be easily done after screwing off the conductive ion emitting head portions 3b, 5b. The sheathing 3a, 5a may be of hose like structure made of silicone or the like.

[0055] Interesting is also the fact that the housing 1 further comprises two rib like wall segments 1d that mechanically protect the ion emitting electrodes 3-5 which are protruding from the housing wall 13, 14. In Fig. 2 those rib like wall segments 1d extend along the electrodes 3-5 such that the electrodes 3-5 are not being damaged by any components moving by the ionization apparatus during industrial operation.

[0056] The two rib like wall segments 1d are each detachably connected to the rest of the housing 1. For easy attachment and detachment the rib like wal segments 1d are connected to the rest of the housing 1 via a snap fit connection. For this snap fit connection the rib like wall segments 1d comprise mounting flaps 1e and 1f that engage the rest of the housing 1 on an upper side and on a lower side.

[0057] It has been noted already that the ionization apparatus with the at least one above noted rib like wall segment 1d shall be claimable as such without the measuring arrangement 6 being necessary.

[0058] According to another teaching a method for detecting an indication for surface housing pollution P on the housing surface of an above noted ionization apparatus is claimed. According to this teaching it is of considerable importance that an above noted measuring arrangement 6 is provided with a measuring electrode 7, 8 connected thereto and that an indication for housing surface pollution P is being detected by the measuring arrangement 6 based on a change in complex resistance Z' between the ion emitting electrode 3-5 and the assigned measuring electrode 7, 8. As this is the normal operation of the above noted ionization apparatus regarding the teaching and regarding preferred embodiments reference may be made to all explanations given for the proposed ionization apparatus.

Claims

1. Ionization apparatus comprising a housing (1) and at least partly within in the housing (1) a high voltage power supply arrangement (2) with at least one ion emitting electrode (3-5) connected thereto, wherein a measuring arrangement (6) with at least one measuring electrode (7, 8) connected thereto is provided for detecting an indication for housing surface pollution (P) based on a change in complex resistance (Z') between at least one said ion emitting electrode (3-5) and at least one said measuring electrode (7, 8),
characterized in
that at least one said ion emitting electrode (3-5) and at least one said measuring electrode (7, 8) are located on opposite sides of a housing wall (13, 14) which surface pollution is to be detected.

2. Ionization apparatus according to claim 1, characterized in that for ionization the high voltage power supply arrangement (2) supplies high voltage with an AC-component to at least one said ion emitting electrode (3-5) against ground potential (9), preferably, that the high voltage power supply arrangement (2) supplies a modulated, preferably pulsed DC-voltage to at least one said ion emitting electrode (3-5) against ground potential (9).

3. Ionization apparatus according to claim 2, characterized in that the value of the modulated, preferably pulsed, DC-voltage lies between 2 kV and 60 kV, preferably between 20 kV and 40 kV, and/or, wherein the pulse frequency lies between 0,5 Hz and 100 Hz, preferably between 1 Hz and 10 Hz.

4. Ionization apparatus according to one of the preceding claims, characterized in that multiple ion emitting electrodes (3-5) are provided and that at least some of the ion emitting electrodes (3-5) are each or as an electrode-group assigned at least one said measuring electrode (7, 8) for detecting an indication for housing surface pollution (P) based on a change in complex resistance (Z') between the respective ion emitting electrode (3-5) or electrodes (3-5) and the respective measuring electrode (7, 8) or electrodes (7, 8), preferably, that for ionization the high voltage power supply arrangement (2) supplies modulated, preferably pulsed, positive high DC-voltage to a first electrode-group of ion emitting electrodes (3, 4) against ground potential and modulated, preferably pulsed, negative high DC-voltage to a second electrode-group of ion emitting electrodes (5) against ground potential (9).

5. Ionization apparatus according to claim 4, characterized in that the high voltage power supply arrangement (2) synchronizes the voltages supplied to the ion emitting electrodes (3-5) such that during operation, in an alternating manner, the first electrode-group is supplied with a preferably low reference voltage, preferably with ground potential (9), and the second electrode-group is provided with high positive DC-voltage and then the first electrode-group is supplied with high negative DC-voltage and the second electrode-group is supplied with the reference voltage, preferably with ground potential (9).

6. Ionization apparatus according to one of the preceding claims, characterized in that the measuring arrangement (2) evaluates the voltage against ground potential (9) at at least one said measuring electrode (7, 8) during ionization.

7. Ionization apparatus according to one of the preceding claims, characterized in that the measuring arrangement (2) comprises a comparator unit (10) which compares the voltage against ground potential (9) at at least one said measuring electrode (7, 8) to a threshold value (V_ref) and outputs a signal (CLB) depending on the result of the comparison, preferably, that the measuring arrangement (6) comprises a rectifier (11) and/or a filter (12), preferably a lowpass filter, between at least one said measuring electrode (7, 8) and the comparator unit (10).

8. Ionization apparatus according to one of the preceding claims, characterized in that at least one said measuring electrode (7, 8) is provided in addition to the ion emitting electrode (3-5) or ion emitting electrodes (3-5), or, that a ion emitting electrode (3-5) is used as a measuring electrode (7, 8).

9. Ionization apparatus according to one of the preceding claims, characterized in that at least one said ion emitting electrode (3-5) and at least one said measuring electrode (7, 8) are located offset from one another along the housing wall (13, 14) which surface pollution is to be detected, further preferably, that the housing wall (13, 14) which surface pollution is to be detected is made of a plastic material, preferably of PVC.

10. Ionization apparatus according to one of the preceding claims, characterized in that at least one said measuring electrode (7, 8) is located close to the respective side of the housing wall (13, 14) which surface pollution (P) is to be detected, preferably that at least one said measuring electrode (7, 8) is in contact to the respective side of the housing wall (13, 14), further preferably, that at least one said measuring electrode (7, 8) is spring tensioned against the respective side of the housing wall (13, 14).

11. Ionization apparatus according to one of the preceding claims, characterized in that the housing (1) comprises at least one rib like wall segment (1a) that mechanically protects at least one said ion emitting electrode (3-5) protruding from a housing wall (13, 14) and that the at least one rib like wall segment (1d) is detachably connected to the rest of the housing (1), preferably, that the rib like wall segment (1d) is connected to the rest of the housing (1) via a snap fit connection.

12. A method for detecting an indication for surface housing pollution (P) on the housing surface of an ionization apparatus with a high voltage power supply arrangement (2) with at least one ion emitting electrode (3-5) connected thereto, wherein a measuring arrangement (6) with at least one measuring electrode (7, 8) connected thereto is provided and that an indication for housing surface pollution (P) is being detected by the measuring arrangement (6) based on a change in complex resistance (Z') between at least one said ion emitting electrode (3-5) and at least one said measuring electrode (7, 8),
characterized in
that at least one said ion emitting electrode (3-5) and at least one said measuring electrode (7, 8) are located on opposite sides of a housing wall (13, 14) which surface pollution is to be detected.

13. Method according to claim 12, characterized in that via the high voltage power supply arrangement (2) a modulated, preferably pulsed, positive high DC-voltage is being supplied to a first electrode-group of ion emitting electrodes (3, 4) against ground potential (9) and a modulated, preferably pulsed, negative high DC-voltage is being supplied to a second electrode-group of ion emitting electrodes (5) against ground potential (9), preferably, that via the high voltage power supply arrangement (2) the voltages supplied to the ion emitting electrodes (3-5) are being synchronized such that during operation, in an alternating manner, the first electrode-group is supplied with a preferably low reference voltage, preferably with ground potential (9), and the second electrode-group is provided with high positive DC-voltage and then the first electrode-group is supplied with high negative DC-voltage and the second electrode-group is supplied with the reference voltage, preferably with ground potential (9).

14. Method according to claim 12 or 13, characterized in that via the measuring arrangement (6) the voltage against ground potential (9) at at least one said measuring electrode (7, 8) is being evaluated during ionization.

15. Method according to one of the claims 12 to 14, characterized in that via the measuring arrangement (6) the voltage against ground potential (9) at at least one said measuring electrode (7, 8) is being compared to a threshold value (V_ref) and depending on the result of the comparison a signal (CLB) is being output.

Ansprüche

1. Ionisierungseinrichtung, die ein Gehäuse (1) und wenigstens teilweise innerhalb des Gehäuses (1) eine Hochspannungsversorgungsanordnung (2) mit wenigstens einer damit verbundenen ionenemittierenden Elektrode (3-5) umfasst, wobei eine Messanordnung (6) mit wenigstens einer damit verbundenen Messelektrode (7, 8) zum Detektieren eines Anzeichens für Gehäuseoberflächenverschmutzung (P) basierend auf einer Änderung eines komplexen Widerstands (Z') zwischen der wenigstens einen ionenemittierenden Elektrode (3-5) und der wenigstens einen Messelektrode (7,8) bereitgestellt ist,
dadurch gekennzeichnet, dass
sich die wenigstens eine ionenemittierende Elektrode (3-5) und die wenigstens eine Messelektrode (7, 8) auf gegenüberliegenden Seiten einer Gehäusewand (13, 14), deren Oberflächenverschmutzung zu detektieren ist, befinden.

2. Ionisierungseinrichtung nach Anspruch 1, dadurch gekennzeichnet, dass die Hochspannungsversorgungsanordnung (2) für eine Ionisierung eine Hochspannung gegen Erdpotential (9) mit einer Wechselstromkomponente an die wenigstens eine ionenemittierende Elektrode (3-5) liefert, bevorzugt, dass die Hochspannungsversorgungsanordnung (2) eine modulierte, bevorzugt gepulste, Gleichspannung gegen Erdpotential (9) an die wenigstens eine ionenemittierende Elektrode (3-5) liefert.

3. Ionisierungseinrichtung nach Anspruch 2, dadurch gekennzeichnet, dass der Wert der modulierten, bevorzugt gepulsten, Gleichspannung zwischen 2 kV und 60 kV, bevorzugt zwischen 20 kV und 40 kV, liegt, und/oder wobei die Pulsfrequenz zwischen 0,5 Hz und 100 Hz, bevorzugt zwischen 1 Hz und 10 Hz, liegt.

4. Ionisierungseinrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass mehrere ionenemittierende Elektroden (3-5) bereitgestellt sind und dass wenigstens manche der ionenemittierenden Elektroden (3-5) jeweils einzeln oder als eine Elektrodengruppe der wenigstens einen Messelektrode (7, 8) zum Detektieren eines Anzeichens einer Gehäuseoberflächenverschmutzung (P) basierend auf einer Änderung eines komplexen Widerstands (Z') zwischen der jeweiligen ionenemittieren Elektrode (3-5) oder den jeweiligen ionenemittierenden Elektroden (3-5) und der jeweiligen Messelektrode (7, 8) oder den jeweiligen Messelektroden (7, 8) zugewiesen sind, bevorzugt, dass die Hochspannungsversorgungsanordnung (2) für eine Ionisierung eine modulierte, bevorzugt gepulste, positive Gleichstrom-Hochspannung gegen Erdpotential an eine erste Elektrodengruppe aus ionenemittierenden Elektroden (3,4) und eine modulierte, bevorzugt gepulste, negative Gleichstrom-Hochspannung gegen Erdpotential (9) an eine zweite Elektrodengruppe aus ionenemittierenden Elektroden (5) liefert.

5. Ionisierungseinrichtung nach Anspruch 4, dadurch gekennzeichnet, dass die Hochspannungsversorgungsanordnung (2) die an die ionenemittierenden Elektroden (3-5) gelieferten Spannungen so synchronisiert, dass während des Betriebs abwechselnd die erste Elektrodengruppe mit einer bevorzugt niedrigen Referenzspannung, bevorzugt mit Erdpotential (9), versorgt wird und die zweite Elektrodengruppe mit einer positiven Gleichstrom-Hochspannung versorgt wird und anschließend die erste Elektrodengruppe mit einer negativen Gleichstrom-Hochspannung versorgt wird und die zweite Elektrodengruppe mit der Referenzspannung, bevorzugt mit Erdpotential (9), versorgt wird.

6. Ionisierungseinrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass die Messanordnung (2) während einer Ionisierung die Spannung gegen Erdpotential (9) an der wenigstens einen Messelektrode (7, 8) auswertet.

7. Ionisierungseinrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass die Messanordnung (2) eine Komparatoreinheit (10) umfasst, die die Spannung gegen Erdpotential (9) an der wenigstens einen Messelektrode (7, 8) mit einem Schwellenwert (V_ref) vergleicht und ein Signal (CLB) ausgibt, das von dem Ergebnis des Vergleichs abhängt, bevorzugt, dass die Messanordnung (6) einen Gleichrichter (11) und/oder ein Filter (12), bevorzugt ein Tiefpassfilter, zwischen der wenigstens einen Messelektrode (7, 8) und der Komparatoreinheit (10) umfasst.

8. Ionisierungseinrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass die wenigstens eine Messelektrode (7, 8) zusätzlich zu der ionenemittierenden Elektrode (3-5) oder den ionenemittierenden Elektroden (3-5) bereitgestellt ist, oder dass eine ionenemittierende Elektrode (3-5) als eine Messelektrode (7, 8) verwendet wird.

9. Ionisierungseinrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass sich die wenigstens eine ionenemittierende Elektrode (3-5) und die wenigstens eine Messelektrode (7, 8) entlang der Gehäusewand (13, 14), deren Oberflächenverschmutzung zu detektieren ist, zueinander versetzt befinden, weiter bevorzugt, dass die Gehäusewand (13, 14), deren Oberflächenverschmutzung zu detektieren ist, aus einem Kunststoffmaterial, bevorzugt aus PVC, gefertigt ist.

10. Ionisierungseinrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass sich die wenigstens eine Messelektrode (7, 8) nahe zu der jeweiligen Seite der Gehäusewand (13, 14), deren Oberflächenverschmutzung (P) zu detektieren ist, befindet, bevorzugt, dass sich die wenigstens eine Messelektrode (7, 8) in Kontakt mit der jeweiligen Seite der Gehäusewand (13, 14) befindet, weiter bevorzugt, dass die wenigstens eine Messelektrode (7, 8) mit einer Feder gegen die jeweilige Seite der Gehäusewand (13, 14) gespannt ist.

11. Ionisierungseinrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, dass das Gehäuse (1) wenigstens ein lamellenartiges Wandsegment (1a) umfasst, das die wenigstens eine ionenemittierende Elektrode (3-5), die von einer Gehäusewand (13, 14) hervorsteht, schützt, und dass das wenigstens eine lamellenartige Wandsegment (1d) mit dem Rest des Gehäuses (1) trennbar verbunden ist, bevorzugt, dass das lamellenartige Wandsegment (1d) mit dem Rest des Gehäuses (1) mittels einer Einschnappverbindung verbunden ist.

12. Verfahren zum Detektieren eines Anzeichens einer Oberflächengehäuseverschmutzung (P) auf der Gehäuseoberfläche einer Ionisierungseinrichtung mit einer Hochspannungsversorgungsanordnung (2) mit wenigstens einer damit verbundenen ionenemittierenden Elektrode (3-5), wobei eine Messanordnung (6) mit wenigstens einer damit verbundenen Messelektrode (7, 8) bereitgestellt wird und wobei ein Anzeichen für eine Gehäuseoberflächenverschmutzung (P) durch die Messanordnung (6) basierend auf einer Änderung eines komplexen Widerstands (Z') zwischen der wenigstens einen ionenemittierenden Elektrode (3-5) und der wenigstens einen Messelektrode (7, 8) detektiert wird, dadurch gekennzeichnet, dass
sich die wenigstens eine ionenemittierende Elektrode (3-5) und die wenigstens eine Messelektrode (7, 8) auf gegenüberliegenden Seiten einer Gehäusewand (13, 14), deren Oberflächenverschmutzung zu detektieren ist, befinden.

13. Verfahren nach Anspruch 12, dadurch gekennzeichnet, dass eine modulierte, bevorzugt gepulste, positive Gleichstrom-Hochspannung gegen Erdpotential (9) mittels der Hochspannungsversorgungsanordnung (2) an eine erste Elektrodengruppe aus ionenemittierenden Elektroden (3, 4) geliefert wird und dass eine modulierte, bevorzugt gepulste, negative Gleichstrom-Hochspannung gegen Erdpotential (9) an eine zweite Elektrodengruppe aus ionenemittierenden Elektroden (5) geliefert wird, bevorzugt, dass die mittels der Hochspannungsversorgungsanordnung (2) an die ionenemittierenden Elektroden (3, 5) gelieferten Spannungen so synchronisiert werden, dass während des Betriebs abwechselnd die erste Elektrodengruppe mit einer bevorzugt niedrigen Referenzspannung, bevorzugt mit Erdpotential (9), versorgt wird und die zweite Elektrodengruppe mit einer positiven Gleichstrom-Hochspannung versorgt wird und anschließend die erste Elektrodengruppe mit einer negativen Gleichstrom-Hochspannung versorgt wird und die zweite Elektrodengruppe mit der Referenzspannung, bevorzugt mit Erdpotential (9), versorgt wird.

14. Verfahren nach Anspruch 12 oder 13, dadurch gekennzeichnet, dass die Spannung gegen Erdpotential (9) während einer Ionisierung an der wenigstens einen Messelektrode (7, 8) mittels der Messanordnung (6) ausgewertet wird.

15. Verfahren nach einem der Ansprüche 12 bis 14, dadurch gekennzeichnet, dass die Spannung gegen Erdpotential (9) an der wenigstens einen Messelektrode (7, 8) mittels der Messanordnung (6) mit einem Schwellenwert (V_ref) verglichen wird und dass ein Signal (CLB), das von dem Ergebnis des Vergleichs abhängt, ausgegeben wird.

Revendications

1. Appareil d'ionisation comprenant un logement (1) et un agencement (2) d'alimentation en énergie à haute tension auquel est raccordée au moins une électrode (3-5) émettrice d'ions et disposé au moins en partie à l'intérieur du logement (1), un agencement de mesure (6) auquel est raccordée au moins une électrode de mesure (7, 8) étant prévu pour détecter une indication d'une pollution (P) de la surface du logement sur la base d'une modification de la résistance complexe (Z') entre au moins l'une desdites électrodes (3-5) émettrices d'ions et au moins l'une desdites électrodes de mesure (7, 8),
caractérisé en ce que
ladite ou lesdites électrodes (3-5) émettrices d'ions et au moins l'une desdites électrodes de mesure (7, 8) sont situées sur des côtés opposés de la paroi (13, 14) du logement dont la pollution de surface doit être détectée.

2. Appareil d'ionisation selon la revendication 1, caractérisé en ce que pour l'ionisation, l'agencement (2) d'alimentation en énergie à haute tension délivre une haute tension présentant une composante de courant alternatif à au moins l'une desdites électrodes (3-5) émettrices d'ions par rapport au potentiel de masse (9) et de préférence en ce que l'agencement (2) d'alimentation en énergie à haute tension délivre une tension continue modulée, de préférence pulsée, à au moins l'une desdites électrodes (3-5) émettrices d'ions par rapport à un potentiel de masse (9).

3. Appareil d'ionisation selon la revendication 2, caractérisé en ce que la valeur de la tension continue modulée et de préférence pulsée est comprise entre 2 kV et 60 kV, de préférence entre 20 kV et 40 kV et/ou dans lequel la fréquence des impulsions est située entre 0,5 Hz et 100 Hz et de préférence entre 1 Hz et 10 Hz.

4. Appareil d'ionisation selon l'une des revendications précédentes, caractérisé en ce que plusieurs électrodes (3-5) émettrices d'ions sont prévues et en ce qu'au moins certaines des électrodes (3-5) émettrices d'ions sont attribuées individuellement ou en tant que groupe d'électrodes à au moins l'une desdites électrodes de mesure (7, 8) pour détecter une indication de la pollution (P) de la surface du logement sur la base d'une modification de la résistance complexe (Z') entre la ou les électrodes (3-5) émettrices d'ions respectives et la ou les électrodes de mesure (7, 8) respectives et de préférence en ce que pour l'ionisation, l'agencement (2) d'alimentation en énergie à haute tension délivre une haute tension continue positive, modulée et de préférence pulsée, à un premier groupe d'électrodes (3, 4) émettrices d'ions par rapport au potentiel de masse et une haute tension continue négative, modulée et de préférence pulsée, à un deuxième groupe d'électrodes (5) émettrices d'ions par rapport au potentiel de masse (9).

5. Appareil d'ionisation selon la revendication 4, caractérisé en ce que l'agencement (2) d'alimentation en énergie à haute tension synchronise les tensions délivrées aux électrodes (3-5) émettrices d'ions de telle sorte qu'en fonctionnement, le premier groupe d'électrodes est alimenté en alternance à une tension de référence de préférence basse, de préférence au potentiel de masse (9) et le deuxième groupe d'électrodes est alimenté à une haute tension continue positive, le premier groupe d'électrodes étant ensuite alimenté à une haute tension continue négative et le deuxième groupe d'électrodes est alimenté à la tension de référence, de préférence au potentiel de masse (9).

6. Appareil d'ionisation selon l'une des revendications précédentes, caractérisé en ce que pendant l'ionisation, l'agencement de mesure (2) évalue la tension par rapport au potentiel de masse (9) sur au moins l'une desdites électrodes de mesure (7, 8).

7. Appareil d'ionisation selon l'une des revendications précédentes, caractérisé en ce que l'agencement de mesure (6) comprend une unité de comparateur (10) qui compare la tension par rapport au potentiel de masse (9) d'au moins l'une desdites électrodes de mesure (7, 8) à une valeur de seuil (V_ref) et délivre un signal (CLB) qui dépend du résultat de la comparaison et de préférence en ce que l'agencement de mesure (6) comprend un redresseur (11- et/ou un filtre (12), de préférence un filtre passe-bas, entre au moins l'une desdites électrodes de mesure (7, 8) et l'unité de comparateur (10).

8. Appareil d'ionisation selon l'une des revendications précédentes, caractérisé en ce qu'au moins l'une desdites électrodes de mesure (7, 8) est prévue en plus de l'électrode (3-5) émettrice d'ions ou des électrodes (3-5) émettrices d'ions ou en ce qu'une électrode (3-5) émettrice d'ions est utilisée comme électrode de mesure (7, 8).

9. Appareil d'ionisation selon l'une des revendications précédentes, caractérisé en ce qu'au moins l'une desdites électrodes (3-5) émettrices d'ions et au moins l'une desdites électrodes de mesure (7, 8) sont décalées l'une par rapport à l'autre sur la paroi (13, 14) du logement dont la pollution de surface doit être détectée et de préférence en ce que la paroi (13, 14) du logement dont la pollution de surface doit être détectée est réalisée en matière plastique et de préférence en PVC.

10. Appareil d'ionisation selon l'une des revendications précédentes, caractérisé en ce qu'au moins l'une desdites électrodes de mesure (7, 8) est située à proximité du côté respectif de la paroi (13, 14) du logement dont la pollution (P) de surface doit être détectée, de préférence en ce qu'au moins l'une desdites électrodes de mesure (7, 8) est en contact avec le côté respectif de la paroi (13, 14) du logement et de façon encore plus préférable en ce qu'au moins l'une desdites électrodes de mesure (7, 8) est repoussée élastiquement contre le côté respectif de la paroi (13, 14) du logement.

11. Appareil d'ionisation selon l'une des revendications précédentes, caractérisé en ce que le logement (1) comprend au moins un segment (1a) de paroi en forme de nervure qui protège mécaniquement la ou lesdites électrodes émettrices d'ions (3-5) qui débordent d'une paroi (13, 14) du logement, en ce que le ou les segments (1d) de paroi en forme de nervure sont reliés de manière libérable au reste du logement (1) et de préférence en ce que le segment (1d) de paroi en forme de nervure est relié au reste du logement (1) par une liaison à accrochage élastique.

12. Procédé de détection d'une indication d'une pollution (P) de la surface du logement d'un appareil d'ionisation qui présente un agencement (2) d'alimentation en énergie à haute tension auquel est raccordée au moins une électrode (3-5) émettrice d'ions, un agencement de mesure (6) auquel est reliée au moins une électrode de mesure (7, 8) étant prévu et une indication de la pollution (P) de la surface du logement étant détectée par l'agencement de mesure (6) sur la base d'une modification de la résistance complexe (Z') entre au moins l'une desdites électrodes (3-5) émettrices d'ions et au moins l'une desdites électrodes de mesure (7, 8),
caractérisé en ce que
au moins l'une desdites électrodes (3-5) émettrices d'ions et au moins l'une desdites électrodes de mesure (7, 8) sont disposées sur des côtés opposés d'une paroi (13, 14) du logement dont la pollution de surface doit être détectée.

13. Procédé selon la revendication 12, caractérisé en ce que par l'intermédiaire de l'agencement (2) d'alimentation en énergie à haute tension, une haute tension continue positive, modulée et de préférence pulsée, est délivrée à un premier groupe d'électrodes (3-4) émettrices d'ions par rapport au potentiel de masse (9) et une haute tension négative continue, modulée et de préférence pulsée, est délivrée à un deuxième groupe d'électrodes (5) émettrices d'ions par rapport au potentiel de masse (9), de préférence en ce que par l'intermédiaire de l'agencement (2) d'alimentation en énergie à haute tension les tensions délivrées aux électrodes (3-5) émettrices d'ions sont synchronisées de telle sorte qu'en fonctionnement, le premier groupe d'électrodes est alimenté en alternance à une tension de référence de préférence basse, de préférence au potentiel de masse (9) et le deuxième groupe d'électrodes est alimenté à une haute tension continue positive, le premier groupe d'électrodes étant ensuite alimenté à une haute tension continue négative et le deuxième groupe d'électrodes est alimenté à la tension de référence, de préférence au potentiel de masse (9).

14. Procédé selon les revendications 12 ou 13, caractérisé en ce que pendant l'ionisation, la tension par rapport au potentiel de masse (9) d'au moins l'une desdites électrodes de mesure (7, 8) est évaluée par l'intermédiaire de l'agencement de mesure (6).

15. Procédé selon l'une des revendications 12 à 14, caractérisé en ce que par l'intermédiaire de l'agencement de mesure (6), la tension par rapport au potentiel de masse (9) d'au moins l'une desdites électrodes de mesure (7, 8) est comparée à une valeur de seuil (V_ref) et un signal (CLB) est délivré selon le résultat de la comparaison.

Drawing