JP2011031127A - Dust collector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To recover dust collecting efficiency by stopping energization for a specific time, when a dust collector is energized for a long period of time, since there is such the problem that dust collection efficiency is lowered when the energization is continued at all times for a long period of time. <P>SOLUTION: A dust collector includes a dust collection section 4 in which at least either one of an electrode plate 5 for repelling dust and an electrode plate 6 for collecting dust is covered with an insulator and in which the dust repelling electrode plate 5 and the dust collecting electrode plate 6 are alternately stacked. Also, the dust collector includes a voltage application stopping means 12 by which a voltage applied to the electrode plate 5 for repelling dust and to the electrode plate 6 for collecting dust is stopped for a specific time. After the voltage application is stopped only for a specific time, the voltage application is resumed. Consequently, the phenomenon of lowering of dust collecting efficiency is improved since a potential difference between the electrode plate 5 for repelling dust and the electrode plate 6 for collecting dust is lowered due to failure of the electrode plates covered with the insulator. Thus, the dust collector has a function in which the potential difference can be stabilized to a specification value between the electrode plate 5 for repelling dust and the electrode plate 6 for collecting dust. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a dust collector for removing particulate suspended matters in the air in the field of air purification.

  Particulate suspended matter in the air, that is, dust, has been known as a cause of illnesses such as asthma and has been a target for removal in the past, but in recent studies, the particle size is 2.5 micrometers or less. There is a report that dust (so-called PM2.5) may induce diseases such as lung cancer, and further improvement of the collection technology is required. Among them, dust collectors that use electrostatic precipitating technology are excellent at collecting small particles with a particle size of micrometer or less, and have a low-pressure loss characteristic. There is a need for improved performance.

  Conventionally, as a dust collector of this type, a charging unit that charges dust by electric discharge is provided in the previous stage, and electrodes are stacked in the subsequent stage, and different voltages are applied alternately to form an electric field to collect charged dust. The thing which provided the dust collection part which collects is known.

  As an example to which this configuration is applied, Patent Document 1 discloses a dust collector in which an electrode to which one voltage is applied in a dust collector is covered with a resin film as an insulator.

  Hereinafter, the dust collector will be described with reference to FIG.

  As shown in FIG. 6, the charging unit 101 includes a linear charging unit discharge electrode 102 and a charging unit counter electrode plate 103, and a voltage application electrode plate 105 and a dust collecting electrode plate on the downstream side of the charging unit 101. A dust collecting section 104 is provided in which 106 and 106 are alternately stacked at a predetermined interval.

  Although not shown in the figure, the voltage application electrode plate 105 is covered with a resin film which is an insulator. Usually, in the charging unit 101, 5 to 15 kV is provided between the charging unit discharge electrode 102 and the charging unit counter electrode plate 103, and 2 between the voltage applying electrode plate 105 and the dust collecting electrode plate 106 of the dust collecting unit 104. A predetermined voltage is applied to each electrode by the high voltage power source 107 so as to give a potential difference of ˜6 kV.

  In the above configuration, in the charging unit 101, an unequal electric field is created between the charging unit discharge electrode 102 and the charging unit counter electrode plate 103. At this time, in the vicinity of the charging unit discharge electrode 102 having a linear shape, A very strong electric field is created. For this reason, the charge-holding substance that is slightly contained in the air, such as air ions, is accelerated and collides with the air molecules, and the electrons are separated from the air molecules. The separated electrons are also accelerated and collide with air molecules, and the electrons are separated from the air molecules. The phenomenon where electrons are separated from air molecules by collision with electrons is called ionization.

  In addition, the phenomenon that a large number of electrons separate from air molecules by repeated ionization is called electron avalanche, but positive polarity air ions separated by this avalanche, or negative polarity air combined with separated electrons. Ions are created.

  Then, air ions having a polarity different from that of the charged portion discharge electrode 102 are absorbed by the charged portion discharge electrode 102 and returned to air molecules, and conversely, air ions having the same polarity are repelled from the charged portion discharge electrode 102 by the electric field. Is received and diffused in the direction of the charged portion counter electrode plate 103.

  The discharge phenomenon in which the air near the charged portion discharge electrode 102 is turned into air ions by causing ionization and electron avalanche is called corona discharge. The discharge phenomenon is generated by corona discharge and mainly has the same polarity as the charged portion discharge electrode 102. As the ions adhere to the dust passing through the charging unit 101, the dust is charged.

  The charged dust is introduced into the dust collecting portion 104 along the flow of the air flow, and adheres mainly to the dust collecting electrode plate 106 under the force of the electric field created between the voltage applying electrode plate 105 and the dust collecting electrode plate 106. Then, clean air is blown out from behind the dust collecting unit 104.

  Since the voltage application electrode plate is covered with an insulating resin film, it does not cause a short circuit even when it comes into contact with the dust collection electrode plate, and at the same time prevents spark discharge (hereinafter referred to as spark) that may occur between the electrode plate and the dust collection electrode plate. It has a structure to do.

Japanese Patent No. 3261167

  In such a conventional dust collector, there is an advantage that it is possible to prevent a spark, but if a voltage is continuously applied for a long period of time, the electric charge appearing on the surface of the insulator gradually disappears, and the potential difference with the opposing electrode is reduced. Since the intensity of the electric field decreases and the electric field strength decreases, there is a problem that the dust collection efficiency is lowered, and it is required to maintain the dust collection efficiency high. The present invention solves such a conventional problem, and when the voltage application is stopped after energization for a long time, a charge corresponding to the lowered voltage appears on the surface of the insulator but gradually disappears. If a charge amount corresponding to 0V is in a state of 0, and then a voltage is applied, a charge corresponding to the applied voltage appears again on the surface of the insulator and corresponds to an applied voltage between the opposing electrode and the insulator. Since it becomes possible to give a potential difference and a strong electric field can be obtained, by stopping energization for a certain period of time, the dust collection efficiency is restored or the polarity of the potential is reversed immediately after the polarity is reversed. An object of the present invention is to provide a dust collecting device that can recover the dust collection efficiency by returning to the original state.

  In order to achieve the above-mentioned goal, the dust collector of the present invention covers at least one of the dust repellent electrode plate and the dust collecting electrode plate with an insulator, and alternately places the dust repellent electrode plate and the dust collecting electrode plate. Provided with a dust collecting section that is laminated, and provided with an applied voltage stopping means for stopping the applied voltage applied to the dust repellent electrode plate and the collected electrode plate for a certain period of time, and after the applied voltage is stopped for a certain period of time, the applied voltage is applied again It is. When energized for a long time by this means, a dust collector capable of recovering dust collection efficiency can be obtained by stopping energization for a certain period of time.

  Further, the other means includes a dust collecting portion in which at least one of the dust repellent electrode plate and the dust collecting electrode plate is covered with an insulator, and the dust repellent electrode plate and the dust collecting electrode plate are alternately stacked, Potential polarity changing means for changing the polarity of the potential applied to the repulsive electrode plate and the dust collecting electrode plate is provided, and the potential polarity is changed and then returned to the original polarity. When energized for a long time by this means, a dust collector capable of recovering dust collection efficiency can be obtained by returning immediately after reversing the polarity of the potential.

  Another means is provided with a dust collecting section in which the electrode plates are covered with an insulator, and the electrode plates are alternately stacked so that the polarities of the electrode plate terminals connected to the electrode plates are alternated. Potential polarity changing means for changing the polarity of the potential applied to the electrode plate terminal of the electrode plate is provided, and the polarity of the potential is alternately changed at regular time intervals. When energized for a long time by this means, a dust collector that maintains high dust collection performance can be obtained by reversing the dust repulsion electrode side and the dust collection electrode side by reversing the polarity of the potential.

  Another means is that the applied voltage stop means is a timer switch.

  As another means, the potential polarity changing means is a timer switch.

  The other means is provided with a detecting means for detecting the timing for starting the applied voltage stopping means.

  Another means is provided with a detecting means for detecting the timing for starting the potential polarity changing means.

  Another means is that the detection means is a dust concentration detection means for detecting the dust concentration before and after the dust collecting portion.

  Another means is that the detecting means is a dirt detecting means for detecting dirt on the dust collecting portion.

  According to the present invention, since dust collection efficiency can be maintained high, it is possible to provide a dust collector that does not deteriorate in performance when used constantly.

The perspective view which shows the structure of Embodiment 1 of this invention. The perspective view which shows the structure of Embodiment 2 of this invention. A perspective view showing a configuration when the same potential polarity is changed The perspective view which shows the structure of Embodiment 3 of this invention. The perspective view which shows the structure of Embodiment 4 of this invention. Simplified diagram showing conventional configuration

  According to a first aspect of the present invention, at least one of an electrode plate that repels dust and an electrode plate that collects dust is covered with an insulator, and the electrode plate that repels dust and the electrode plate that collects dust alternately The electrode plate for repelling dust and the applied voltage stopping means for stopping the applied voltage applied to the electrode plate for collecting dust for a certain period of time are provided, and the applied voltage is stopped only for a certain period and then applied again. The voltage is applied, and the potential difference between the electrode plate that repels dust and the electrode plate that collects dust is reduced due to the failure of the electrode plate covered with an insulator, so the phenomenon that dust collection efficiency decreases can be improved. The potential difference between the electrode plate that repels dust and the electrode plate that collects dust can be stabilized to the initial specification.

  According to a second aspect of the present invention, at least one of an electrode plate that repels dust and an electrode plate that collects dust is covered with an insulator, and the electrode plate collects dust with the electrode plate that repels dust. The electrode plate for repelling dust and the potential polarity changing means for changing the polarity of the potential applied to the electrode plate for collecting dust, and after changing the polarity of the potential, the original polarity The potential difference between the electrode plate that repels dust and the electrode plate that collects dust is reduced due to the failure of the electrode plate covered with an insulator, which can improve the phenomenon that dust collection efficiency is reduced. The potential difference between the electrode plate that repels the dust and the electrode plate that collects dust can be maintained.

  According to a third aspect of the present invention, there is provided a dust collecting portion in which the electrode plates are alternately laminated so that the electrode plates are covered with an insulator and the polarity of the electrode plate terminals connected to the electrode plates are alternated. Provided with a potential polarity changing means for changing the polarity of the potential applied to the electrode plate terminals of the alternately stacked electrode plates, and alternately changing the polarity of the potential at regular time intervals. Since the potential difference between the electrode plates is reduced due to the failure of the covered electrode plates, the phenomenon that the dust collection efficiency is reduced can be improved, and the potential difference between the electrode plates can be maintained.

  The invention according to claim 4 of the present invention is such that the applied voltage stop means is a timer switch, and has the effect that the polarity of the potential can be changed at an appropriate time interval.

  Further, according to the fifth aspect of the present invention, the potential polarity changing means is a timer switch, and has the effect that the polarity of the potential can be changed at an appropriate time interval.

  Further, the invention according to claim 6 of the present invention is provided with a detecting means for detecting the timing for starting the applied voltage stopping means, and has an effect that it is possible to appropriately determine the time when the dust collection efficiency is lowered.

  Further, the invention according to claim 7 of the present invention is provided with the detecting means for detecting the timing for starting the potential polarity changing means, and has an effect that it is possible to appropriately determine the time when the dust collection efficiency is lowered.

  In the invention according to claim 8 of the present invention, the detecting means is a dust concentration detecting means for detecting the dust concentration before and after the dust collecting portion, and appropriately determines when the dust collection efficiency is lowered. Has the effect of being able to.

  Further, the invention according to claim 9 of the present invention is that the detecting means is a dirt detecting means for detecting dirt on the dust collecting portion, and has an effect that it is possible to appropriately determine when the dust collecting efficiency is lowered.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
First, the configuration of the first embodiment is shown.

  As shown in FIG. 1, the charging unit 1 is composed of a linear charging unit discharge electrode 2 and a charging unit counter electrode plate 3, and an electrode plate 5 and an electrode plate 6 are fixed to the downstream side of the charging unit 1. Dust collecting portions 4 are provided that are alternately stacked at intervals. Moreover, the electrode plate 5 and the electrode plate 6 are coat | covered with the resin film which is an insulator.

  5 to 15 kV between the charged part discharge electrode terminal 8 communicating with the charged part discharge electrode 2 and the charged part counter electrode plate terminal 9 communicating with the charged part counter electrode plate 3 in the charging unit 1, and the dust collecting unit A predetermined voltage is applied to each electrode by the high-voltage power supply 7 so as to give a potential difference of 2 to 6 kV between the electrode plate terminal 10 communicating with the four electrode plates 5 and the electrode plate terminal 11 communicating with the electrode plate 6. Has been. Here, the electrode plate terminal 10 is a positive electrode, and the electrode plate terminal 11 is a negative electrode.

  Here, the electrode plate 5 is an electrode plate that repels dust, and the electrode plate that repels dust means that dust is repelled by being charged to the positive electrode in the charging unit 1 and having the same polarity. To do.

  The electrode plate 6 is an electrode plate that collects dust, and the electrode plate that collects dust is a Coulomb force applied to the electrode plate that collects dust charged to the positive electrode in the charging unit 1 and has the opposite polarity. It is attracted by and collects dust. Here, the electrode plate 6 for collecting dust is grounded.

  An applied voltage stop means 12 (a timer switch as an example) is installed in the power supply portion of the dust collection unit 4.

  Next, the operation of the first embodiment will be described. In the above configuration, since the dust is charged by adhering to the dust passing through the charging unit 1, the charged dust is introduced into the dust collecting unit 4 along the flow of the air flow, and between the electrode plate 5 and the electrode plate 6. It receives and is removed from the electrode plate 6 that mainly collects dust under the force of the electric field produced, and clean air is blown out from the rear of the dust collecting section 4.

  Here, although the charged dust adheres and accumulates on the electrode plate 6 that collects dust in the dust collecting portion 4, the electrode plate 5 that repels dust when the electrode plate terminal 10 and the electrode plate terminal 11 are energized for a long time. The electric charge present on the surface of the insulating film disappears, and the potential difference between the electrode plate 5 that repels dust and the electrode plate 6 that collects dust decreases, and is thus applied to the electrode plate terminal 10 and the electrode plate terminal 11. The potential difference is smaller than the potential difference, and the dust collection performance of the dust collection unit 4 tends to decrease.

  Therefore, by operating a timer switch as the applied voltage stopping means 12, the applied voltage applied to the electrode plate terminal 10 and the electrode plate terminal 11 is stopped for a short period of time, for example, 3 minutes, thereby repelling dust. 5 can be returned to the initial state, and the potential difference in the initial state can be maintained by adding a potential difference between the electrode plate terminal 10 and the electrode plate terminal 11 again.

When measuring the dust collection efficiency, the dust collector was configured in the order of the charging unit 1, the dust collector 4, and the blower from the upstream side, and air was passed through the dust collector by operating the blower. Here, after applying an applied voltage for 60 minutes between the electrode plate 5 that repels dust in the dust collecting portion 4 and the electrode plate 6 that collects dust, the operation of stopping the applied voltage for 3 minutes is repeated, and 0.3 μm in air The number concentration of dust having the above particle diameter was measured with a laser particle counter and calculated using the following calculation formula.
Dust collection efficiency (%) = (1− (Dust concentration on the upstream side of the charged part) / (Dust concentration on the downstream side of the dust collecting part)) × 100

  Table 1 shows the results where the horizontal axis represents elapsed time and the vertical axis represents dust collection efficiency. Table 1 is a graph showing the results of measuring the change in dust collection efficiency over the elapsed time of Embodiment 1 of the present invention.

(Embodiment 2)
The same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. The structure of Embodiment 2 is shown. As shown in FIG. 2, a potential polarity changing means 13 (a timer changeover switch as an example) is installed in the power supply portion of the dust collecting unit 4.

  Next, the operation of the second embodiment will be described. As shown in FIG. 2 and FIG. 3, by using a timer changeover switch as the potential polarity changing means 13, the electrode plate terminal 10 is positive and the electrode plate terminal 11 is negative as shown in FIG. As shown in FIG. 3, by switching the polarity so that the electrode plate terminal 10 is a negative electrode and the electrode plate terminal 11 is a positive electrode, the potential difference applied to the electrode plate terminal 10 and the electrode plate terminal 11 is changed. Can keep. This prevents a decrease in dust collection performance.

  As an example of the change of the potential polarity, after applying an applied voltage between the electrode plate 5 and the electrode plate 6 of the dust collecting part 4 for 60 minutes, for example, the polarity of the electrode plate 5 and the electrode plate 6 is changed immediately. The operation to return to is repeated.

  As another example, an applied voltage is applied, for example, for 60 minutes between the electrode plate 5 (that is, the electrode plate that repels dust) and the electrode plate 6 (that is, the electrode plate that collects dust) of the dust collecting unit 4. Later, the polarity of the electrode plate 5 and the electrode plate 6 is changed and the polarity is switched, that is, the electrode plate 5 is used as an electrode for collecting dust and the electrode plate 6 is used as an electrode for repelling dust, for example, for 60 minutes. It repeats this operation.

(Embodiment 3)
The same parts as those in the first embodiment and the second embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. The structure of Embodiment 3 is shown. As shown in FIG. 4, a particle counter as a dust concentration detecting means 14 is provided on the upstream side of the charging unit 1 and the downstream side of the dust collecting unit 4.

  Next, the operation of the third embodiment will be described. By measuring the dust concentration upstream of the charging unit and the dust concentration downstream of the dust collecting unit with the dust concentration detecting means 14, the dust collecting efficiency is reduced from 90 to 95% by converting the dust collecting efficiency each time. In this case, the dust collection efficiency can be stably increased to a high level for a long time by stopping the applied voltage of the dust collection unit 4 or changing the potential polarity of the electrode plate 5 and the electrode plate 6.

(Embodiment 4)
The same parts as those in the first to third embodiments are denoted by the same reference numerals, and detailed description thereof is omitted. The structure of Embodiment 4 is shown. As shown in FIG. 4, the dirt detection means 15 is provided on the downstream side of the dust collecting unit 4.

  Next, the operation of the fourth embodiment will be described. By measuring the degree of dirt due to dust in the dust collecting part with an infrared-based dust sensor as the dirt detecting means 15, the applied voltage of the dust collecting part 4 is stopped or the potential polarity of the electrode plate 5 and the electrode plate 6 is changed. By changing, the dust collection efficiency can be stably increased to a high level for a long time.

  The dust collector of the present invention is capable of preventing sparks in both the dust collecting part and the charging part while obtaining high dust collecting performance, so that a dust collector that requires high dust collecting performance and safety at the same time, for example, a factory It is useful as a dust collection device to be installed in oil mist dust collectors, household air purifiers, or air supply type ventilation fans.

DESCRIPTION OF SYMBOLS 1 Charge part 2 Charge part discharge electrode 3 Charge part counter electrode plate 4 Dust collection part 5 Electrode plate 6 Electrode plate 7 High voltage power supply 8 Charge part discharge electrode terminal 9 Charge part counter electrode plate terminal 10 Electrode plate terminal 11 Electrode plate terminal 12 Application Voltage stopping means 13 Potential polarity changing means 14 Dust concentration detecting means 15 Dirt detecting means

Claims (9)

At least one of the electrode plate that repels dust and the electrode plate that collects dust is covered with an insulator, and has a dust collection part that alternately stacks the electrode plate that repels dust and the electrode plate that collects dust. A dust collector comprising application voltage stopping means for stopping an applied voltage applied to the electrode plate that repels and the electrode plate that collects dust for a predetermined time, and applying the applied voltage again after stopping the applied voltage for a predetermined time. At least one of the electrode plate that repels dust and the electrode plate that collects dust is covered with an insulator, and has a dust collection part that alternately stacks the electrode plate that repels dust and the electrode plate that collects dust. A dust collector that includes potential polarity changing means for changing a polarity of a potential applied to the electrode plate that repels and the electrode plate that collects dust, and returns the polarity to the original polarity after changing the polarity of the potential. The electrode of the electrode plate that is alternately stacked is provided with a dust collecting portion that covers the electrode plate with an insulator and alternately stacks the electrode plates so that the polarities of the electrode plate terminals that are conducted to the electrode plates are alternated. A dust collector that includes potential polarity changing means for changing the polarity of a potential applied to a plate terminal, and alternately changes the polarity of the potential at regular time intervals. The dust collector according to claim 1, wherein the applied voltage stop means is a timer switch. The dust collector according to claim 2 or 3, wherein the potential polarity changing means is a timer switch. The dust collector according to claim 1, further comprising a detection unit that detects a timing for starting the applied voltage stop unit. The dust collector according to claim 2 or 3, further comprising a detecting means for detecting a timing for starting the potential polarity changing means. The dust collector according to claim 7, wherein the detecting means is a dust concentration detecting means for detecting the dust concentration before and after the dust collecting portion. 8. The dust collecting apparatus according to claim 7, wherein the detecting means is a dirt detecting means for detecting dirt on the dust collecting portion.

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