CN102192951A - Ion concentration measuring circuit and ion current sensor - Google Patents
Ion concentration measuring circuit and ion current sensor Download PDFInfo
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- CN102192951A CN102192951A CN2010101554209A CN201010155420A CN102192951A CN 102192951 A CN102192951 A CN 102192951A CN 2010101554209 A CN2010101554209 A CN 2010101554209A CN 201010155420 A CN201010155420 A CN 201010155420A CN 102192951 A CN102192951 A CN 102192951A
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Abstract
The invention provides an ion concentration measuring circuit capable of properly keeping ion balance and a preferable ion current sensor used in the ion concentration measuring circuit. In the ion concentration measuring circuit, ions which are generated at the periphery of a discharging electrode (101) through corona discharge are collected by an ion current sensor, so that the concentration of the ions can be measured. The ion concentration measuring circuit comprises the ion current sensor (S), a first amplifier (A1), a second amplifier (A2), a third amplifier (A3) and the like, wherein the ion current sensor (S) consists of a first sensor (S1) in which ion current flows in the process of collecting the ions and induced current due to an electric field formed by the discharge electrode (101) flows at the same time, and a second sensor (S2) which is insulated from the first sensor (S1) and by which the surface of a sensor unit (S2a) is insulated from surroundings when the induced current due to the electric field flows in the conductive sensor unit (S2a), so that the ions are not collected by the sensor unit (S2a); and the first amplifier (A1), the second amplifier (A2) and the third amplifier (A3) are used for detecting a difference between the output signal of the first sensor (S1) and the output signal of the second sensor (S2).
Description
Technical field
The present invention relates to utilizing corona discharge to produce negative ions to remove in the electric ion generator to removing electric object, be used to measure the ion concentration measurement circuit of the negative ion concentrations (gas current) that produces by ion generator and the ion current sensor that in this ion concentration measurement circuit, uses.
Background technology
As this ion generator, the known for example ion generator of record in Patent Document 1.
Fig. 7 is the summary construction diagram of the ion generator of record in Patent Document 1, in Fig. 7, and 1 expression fan, 2 expression sparking electrodes (transmitter), 3 expression grids, 4a, 4b represent that 5a, 5b represent amplifier along the ion current sensor of air supply direction configuration, 6a, 6b represent the A/D transducer, 7 expression computing circuits, 8 expression direct current biasing power supplys, 9 indication transformers, 10 expression AC power, 11 expression control parts.
And fan 1, sparking electrode 2 and grid 3 are arranged on the ion generator main body, and near grid 3 ground of this ion generator main body, by suitable holding components maintenance ion current sensor 4a, 4b.
In above-mentioned prior art, obtain respectively the poor of the ion concentration that detects by each ion current sensor 4a, 4b by computing circuit 7, and control the voltage of direct current biasing power supply 8 according to above-mentioned difference, thereby be controlled at sparking electrode 2 around the negative ions amount that produces, with the negative ion concentrations on the electric object removed on the extended line that is equilibrated at air supply direction.
[Patent Document 1] (Japan) spy opens 2005-100870 communique ([0019]～[0030] section, Fig. 1～3 etc.)
Summary of the invention
In the ion generator shown in Fig. 7, structurally that ion current sensor 4a, 4b and ion generator is main body integrated, the distance between sparking electrode 2 and ion current sensor 4a, the 4b does not have so far away.
Therefore, ion current sensor 4a, 4b are when can detecting the negative ions that is produced by sparking electrode 2, be subjected to the electric field effects that formed by sparking electrode 2 greatly, the induction current that is caused by this electric field is detected by ion current sensor 4a, 4b with original gas current.Therefore the leading value of the distance of above-mentioned induction current between sparking electrode 2 and ion current sensor 4a, 4b hour formation is difficult to correctly detect general small gas current.
In order to dispose ion current sensor 4a, 4b electric field influence not to be subjected to cause by sparking electrode 2, considered ion current sensor 4a, 4b and ion generator main body are disposed more discretely, and connect by cable both etc. method, but have cable formation obstacle when removing electric object and move, perhaps cable encloses problem such as give rise to trouble.
As mentioned above, because in the electric current that detects by ion current sensor,, dominate by the induction current that the electric field of sparking electrode causes, so can not correctly detect the generation ratio of the negative ions that produces by ion generator with respect to gas current.Therefore, exist in when starting working the negative ions balance of setting, can occur the problem of deviation after after a while gradually.
On the other hand, the sparking electrode of ion generator has the characteristic of adhering to dust on the top owing to static, so when adhering to dust on sparking electrode, the generation of negative ions is than changing, electric field intensity also can change simultaneously.In addition, owing to the generation ratio of the negative ions that is caused by the dust that adheres to is different with the intensity of variation of electric field intensity, so in the existing ion generator by the output current of the ion current sensor that has added up to gas current and obtained by the induction current that electric field causes control ionic equilibrium, dust adheres to the deviation that has also increased ionic equilibrium further on sparking electrode.
Therefore, the problem to be solved in the present invention provides a kind of ion concentration measurement circuit that can suitably keep ionic equilibrium, and is adapted at the ion current sensor that uses in this ion concentration measurement circuit.
In order to address the above problem, according to the ion concentration measurement circuit of first technical scheme, the ion that is produced around the sparking electrode by corona discharge by the ion current sensor collection comprises to measure its concentration:
Described ion current sensor, it is made of the first sensor and second sensor, on the described first sensor owing to gather described ion the mobile ion electric current and by the electric field that forms by described sparking electrode the sense of movement induced current, described second sensor and this first sensor insulation ground configuration, on described second sensor since described electric field and in the sensor unit of electric conductivity the sense of movement induced current and with the surface of described sensor element and insulation on every side so that described sensor element is not gathered described ion; And
The pick-up unit of the output signal of detection first sensor and the difference of second signal of sensor.
The ion concentration measurement circuit of second technical scheme, in first technical scheme, described pick-up unit comprises: first multiplying arrangement: the output signal to first sensor is amplified; Second multiplying arrangement amplifies second signal of sensor; And differential multiplying arrangement, the difference of the output signal of the output signal of first multiplying arrangement and second multiplying arrangement is amplified.
The ion current sensor of the 3rd technical scheme, it comprises: first sensor, the electric field that is formed by described sparking electrode in the mobile ion electric current causes the sense of movement induced current by gather the ion that is produced by corona discharge around sparking electrode; And second sensor, with this first sensor insulation ground configuration and since described electric field and in the sensor unit of electric conductivity, flow faradic simultaneously with the surface of described sensor element and insulation on every side so that described sensor element is not gathered described ion.
The ion current sensor of the 4th technical scheme, in the 3rd technical scheme, substrate upper comb dent shape in insulativity alternately disposes first and second sensors, and these first and second sensors are connected on the ion generator body that comprises described sparking electrode via cable.
The ion current sensor of the 5th technical scheme in the 3rd technical scheme, forms first and second sensors of shaped like chips, and these first and second sensors are connected on the ion generator body that comprises described sparking electrode via cable.
The ion current sensor of the 6th technical scheme in the 3rd technical scheme, is comprising on the ion generator body of described sparking electrode, clips described sparking electrode and disposes the first sensor and second sensor.
The ion concentration measurement circuit of the 7th technical scheme, the ion that is produced around the sparking electrode by corona discharge by the ion current sensor collection comprises to measure its concentration:
Described ion current sensor, its electric field that is formed by described sparking electrode mobile ion electric current the time by gathering described ion cause flowing faradic first sensor and an end is connected capacitor formation on this first sensor; And
Pick-up unit detects the output signal of first sensor and the output signal that obtains from the other end of described capacitor poor.
According to ion concentration measurement circuit of the present invention and ion current sensor, can measure negative ion concentrations and faradic influence that be not subjected to cause, and can carry out suitable ionic equilibrium control by the electric field that sparking electrode forms.
In addition, because the structure of the circuit structure of ion concentration measurement circuit and ion current sensor is very simple, so the advantage that just can provide by low cost also is provided.
Description of drawings
Fig. 1 is the circuit diagram of the ion concentration measurement circuit of first embodiment of the present invention.
Fig. 2 is the planimetric map of the embodiment of expression ion current sensor.
Fig. 3 is the figure of user mode of the ion current sensor of presentation graphs 2.
Fig. 4 is the figure of another embodiment of expression ion current sensor.
Fig. 5 (a)～Fig. 5 (d) is the figure of the another embodiment of expression ion current sensor.
Fig. 6 is the circuit diagram of the ion concentration measurement circuit of second embodiment of the present invention.
Fig. 7 is the brief configuration figure of expression prior art.
Symbol description
S, S ': ion current sensor
S1: first sensor
S2: second sensor
S2a: sensor unit
S2b: insulating element
A1～A3: amplifier
R1～R11: resistance
C, C1: capacitor
P: substrate
CL: cable
100: the ion generator main body
101: sparking electrode
Embodiment
Below, embodiments of the present invention are described with reference to the accompanying drawings.
At first, Fig. 1 is the circuit diagram of the ion concentration measurement circuit of first embodiment of the present invention.In Fig. 1, S1 is the first sensor that has exposed conductive component, and described conductive component is used for gathering the negative ions that is produced by corona discharge around sparking electrode (not shown).In addition, S2 is set up in parallel with first sensor S1 or keeps appropriate intervals and second sensor that disposes, by the sensor unit S2a that is made of conductive component and in order to make this sensor unit S2a not gather negative ions the insulating element S2b of the surface of sensor unit S2a with insulation is on every side formed.At this, the surface area of the sensor unit S2a of the first sensor S1 and the second sensor S2 equates.
Constitute ion current sensor S by the such first sensor S1 and the second sensor S2.
First sensor S1 is connected to via resistance R 1 on normal phase input end of the first amplifier A1, and the reversed input terminal of amplifier A1 is via resistance R 2 ground connection.And R3 is connected the lead-out terminal of amplifier A1 and the feedback resistance between the reversed input terminal.
Similarly, the sensor unit S2a of the second sensor S2 is connected to via resistance R 4 on normal phase input end of the second amplifier A2, and the reversed input terminal of amplifier A2 is via resistance R 5 ground connection.And R6 is connected the lead-out terminal of amplifier A2 and the feedback resistance between the reversed input terminal.
The lead-out terminal of the first amplifier A1 is connected to via resistance R 7 on the reversed input terminal of the 3rd amplifier A3, and the lead-out terminal of the second amplifier A2 is connected on normal phase input end of the 3rd amplifier A3 via resistance R 8 simultaneously.And this normal phase input end is via resistance R 9 ground connection.In addition, R10 is connected the lead-out terminal of amplifier A3 and the feedback resistance between the reversed input terminal.Further, the lead-out terminal of amplifier A3 is connected to via resistance R 11 on the capacitor C of an end ground connection, and this tie point constitutes the lead-out terminal of entire circuit.
At this, the amplification coefficient of first, second amplifier A1, A2 equates.
In said structure, the first amplifier A1 and resistance R 1～R3 as the positive amplifier constitute first multiplying arrangement that the output signal of first sensor S1 is amplified, constitute second multiplying arrangement that the output signal of the sensor unit S2a of the second sensor S2 is amplified as the second amplifier A2 of positive amplifier and resistance R 4～R6, the 3rd amplifier A3 and resistance R 7～R10 constitute first, the differential multiplying arrangement that the difference of the output signal of second multiplying arrangement is amplified, resistance R 11 and capacitor C constitute the level and smooth and output unit of output of the output signal that makes differential multiplying arrangement.
Next, Fig. 2 is the planimetric map of the embodiment of the ion current sensor S that is made of the above-mentioned first sensor S1 and the second sensor S2 of expression, is alternately to dispose first sensor S1 that the broach shape forms and the example of the second sensor S2 on the substrate P of insulativity.Wherein, first sensor S1 exposes the conductive component that is made of Copper Foil etc., and the second sensor S2 is by by forming from the surface that covers on every side as the conductive component of sensor unit S2a as the diaphragm of insulating element S2b.
Fig. 3 represents ion current sensor S shown in Figure 2 is connected to state on the ion generator main body 100 via cable CL, and above-mentioned cable CL is connected to the input side (end of resistance R 1, R4) of ion concentration measurement circuit shown in Figure 1.In addition, in Fig. 3, the 101st, sparking electrode.
In addition, Fig. 4 represents another embodiment of ion current sensor S, is the first sensor S1 and the second sensor S2 are formed shaped like chips and make both incorporate examples.
Comprise above-mentioned ion current sensor S the ion concentration measurement circuit action be described as follows described.
At first, owing to gathered the negative ions that produces by sparking electrode 101 by applying high voltage generation corona discharge, so in exposing the first sensor S1 of conductive component, flow and the corresponding gas current of negative ion concentrations.Simultaneously, in first sensor S1, the electric field effects that forms by sparking electrode 101 of flowing and the induction current that causes.Therefore, flow out gas current and faradic resultant current from first sensor S1, the output signal of the first amplifier A1 becomes and the corresponding value of above-mentioned resultant current.
On the other hand, in the second sensor S2 that does not expose as the surface of the sensor unit S2a of conductive component, do not gather the negative ions that produces by sparking electrode 101, the induction current that the electric field effects that formed by sparking electrode 101 of only flowing causes.Therefore, the output signal of the second amplifier A2 becomes and the corresponding value of above-mentioned induction current.
Therefore, in the 3rd amplifier A3, amplify, can offset and be equivalent to faradic signal, only extract and be equivalent to the signal of gas current as output signal by difference to the output signal of the output signal of the first amplifier A1 and the second amplifier A2.
Because this output signal has the polarity of the balance of the negative ion concentrations that reflection produces by sparking electrode 101, so by control the method for the amount of bias that is applied to the voltage on the sparking electrode 101 etc. according to above-mentioned polarity, the control ionic equilibrium gets final product.
And the another embodiment of Fig. 5 (a)～(d) expression ion current sensor S is the brief configuration figure that disposes the situation of the first sensor S1 and the second sensor S2 on ion generator main body 100.
That is, can be individually formed the first sensor S1 and the second sensor S2 respectively, and clip the sparking electrode 101 of ion generator main body 100 and dispose two sensor S1, S2 and get final product.In this case, as Fig. 5 (a) and Fig. 5 (b), two sensor S1, S2 relatively can be configured on the both ends or central part of ion generator body 100.Wherein, under the situation of Fig. 5 (a), can will interconnect between two first sensor S1 and between two second sensor S2.
In addition, as Fig. 5 (c) and Fig. 5 (d), can make the quantity of the quantity ratio sensor S2 of sensor S1 or S2 or S1 many.In this case, for example can will be electrically connected between two the second sensor S2 between two first sensor S1 in Fig. 5 (c), in Fig. 5 (d).
Further, for example in the structure of Fig. 5 (c), adopt the first sensor S1 in left side and the second middle sensor S2 to constitute an ion concentration measurement circuit, similarly adopt the first sensor S1 and the second middle sensor S2 on right side to constitute another ion concentration measurement circuit, can obtain mean value simultaneously by the ion concentration of these two ion concentration measurement circuit measurings.
Similarly, in the example of Fig. 5 (d), first sensor S1 that can shared centre, thus the sensor that forms the two groups of first sensor S1 and the second sensor S2 is right, adopts each group to constitute two ion concentration measurement circuit.
As mentioned above, if use as Fig. 2～ion current sensor S shown in Figure 5, the induction current that the electric field by sparking electrode 101 can be caused offsets and measure ion concentration, particularly, even as shown in Figure 5 under the situation of the configuration ion current sensor S sparking electrode 101 near, can not be subjected to above-mentioned electric field effects yet, and measure ion concentration reliably, thereby carry out ionic equilibrium control.
In addition, generation ratio and electric field intensity at the negative ions that causes owing to dust adhering on sparking electrode, even both intensity of variation differences are owing to the induction current that is caused by electric field finally offsets, so also can not worry owing to above-mentioned dust has increased measuring error.
Next, Fig. 6 is the block scheme of expression second embodiment of the present invention.
In this embodiment, between an end of the resistance R 4 of the end of first sensor S1 and amplifier A2 side, connect capacitor C1, constitute ion current sensor S ' by first sensor S1 and capacitor C1, thereby replace the second sensor S2 in first embodiment.
According to first embodiment, exist owing to be connected the length of the cable on the second sensor S2 and influence such as enclose, the capacitive component of the second sensor S2 (capacitance) is not constant, and the situation that the induction current by sensor unit S2a output that is produced by the electric field of sparking electrode 101 neither be constant.
Therefore, in second embodiment, removed the second sensor S2 and between an end of the resistance R 4 of the end of first sensor S1 and amplifier A2 side, connected the capacitor C1 of setting, thereby only will extract amplifier A2 side via above-mentioned capacitor C1 by the induction current that electric field causes from first sensor S1.
Similarly, in this second embodiment, on normal phase input end of the first amplifier A1, flow into gas current and faradic resultant current, and on normal phase input end of the second amplifier A2, only flow into induction current.Therefore, output signal by amplifying the first amplifier A1 by the 3rd amplifier A3 and the output signal of the second amplifier A2 poor, to be equivalent to faradic signal cancellation, thereby can only extract be equivalent to gas current signal as output signal, and can obtain the action effect identical with first embodiment.
Particularly, according to this second embodiment, stably measure ion concentration the time, can simplify the structure of ion current sensor S ', thereby further reduce cost.
Claims (7)
1. ion concentration measurement circuit, the ion that is produced around sparking electrode by corona discharge by the ion current sensor collection is characterized in that to measure its concentration, comprising:
Described ion current sensor, it is made of the first sensor and second sensor, on the described first sensor owing to gather described ion the mobile ion electric current and by the electric field that forms by described sparking electrode the sense of movement induced current, on described second sensor with this first sensor insulation ground configuration, described second sensor since described electric field and in the sensor unit of electric conductivity the sense of movement induced current and with the surface of described sensor element and insulation on every side so that described sensor element is not gathered described ion; And
The pick-up unit of the output signal of detection first sensor and the difference of second signal of sensor.
2. ion concentration measurement circuit according to claim 1 is characterized in that,
Described pick-up unit comprises:
First multiplying arrangement amplifies the output signal of first sensor;
Second multiplying arrangement amplifies second signal of sensor; And
Differential multiplying arrangement amplifies the difference of the output signal of the output signal of first multiplying arrangement and second multiplying arrangement.
3. an ion current sensor is characterized in that, comprising:
First sensor, the electric field that is formed by described sparking electrode in the mobile ion electric current causes the sense of movement induced current by gather the ion that is produced by corona discharge around sparking electrode; And
Second sensor, with this first sensor insulation ground configuration and since described electric field and in the sensor unit of electric conductivity, flow faradic simultaneously with the surface of described sensor element and insulation on every side so that described sensor element is not gathered described ion.
4. ion current sensor according to claim 3 is characterized in that,
Substrate upper comb dent shape in insulativity alternately disposes first and second sensors, and these first and second sensors are connected on the ion generator body that comprises described sparking electrode via cable.
5. ion current sensor according to claim 3 is characterized in that,
Form first and second sensors of shaped like chips, these first and second sensors are connected on the ion generator body that comprises described sparking electrode via cable.
6. ion current sensor according to claim 3 is characterized in that,
Comprising on the ion generator body of described sparking electrode, clipping described sparking electrode and dispose the first sensor and second sensor.
7. ion concentration measurement circuit, the ion that is produced around sparking electrode by corona discharge by the ion current sensor collection is characterized in that to measure its concentration, comprising:
Described ion current sensor, its electric field that is formed by described sparking electrode mobile ion electric current the time by gathering described ion cause flowing faradic first sensor and an end is connected capacitor formation on this first sensor; And
Pick-up unit detects the output signal of first sensor and the output signal that obtains from the other end of described capacitor poor.
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| CN2010101554209A CN102192951A (en) | 2010-03-03 | 2010-03-03 | Ion concentration measuring circuit and ion current sensor |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104871014A (en) * | 2012-11-02 | 2015-08-26 | 席尔瓦有限责任公司伊德里亚分公司 | Device for the insulated measurement of current and a method for the insulated determination of current |
| CN109073579A (en) * | 2016-03-30 | 2018-12-21 | 三井易艾斯环境工程有限公司 | Liquor analysis system |
| TWI647888B (en) * | 2015-09-03 | 2019-01-11 | 日商夏普股份有限公司 | Ion generating device and ion generator |
| CN112881468A (en) * | 2021-01-11 | 2021-06-01 | 海信（山东）空调有限公司 | Anion concentration detection device, control method thereof and air purification equipment |
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Application publication date: 20110921 |