Voltage generating circuit and discharge device

Abstract

To provide a voltage generating circuit and a discharge device capable of increasing the design freedom of a transformer.SOLUTION: A voltage generating circuit 1 includes a transformer 6, a first output terminal 81, and a first pulse adding circuit 71. The transformer 6 includes a primary winding 61 and a secondary winding 62. The first output terminal 81 is electrically connected to a first end 621 of the secondary winding 62 through a first rectifying element D1. The first pulse adding circuit 71 electrically connects the first output terminal 81 to a second end 622 of the secondary winding 62 through a first capacitance component C1.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a voltage generation circuit and a discharge device including a transformer.

Background Art

[0002] As a related art, a voltage generation circuit (power supply device) is known that is used in a static eliminator that generates positive and negative ions by concentrating an electric field on a needle-shaped discharge electrode and removes static electricity with ionized air (for example, see Patent Document 1). The voltage generation circuit according to the related art generates positive and negative ions by boosting a power supply voltage and applying it to the discharge electrode.

[0003] The voltage generation circuit according to the related art includes a transformer, a first rectifier circuit, a second rectifier circuit, and a capacitor. The transformer has a primary winding to which an AC voltage is input and a secondary winding whose first end is connected to ground. The first rectifier circuit has a first diode whose anode is connected to the second end of the secondary winding of the transformer and whose cathode is connected to the positive output terminal. The second rectifier circuit has a second diode that is connected to the second end of the secondary winding, whose cathode is connected to the second end, and whose anode is connected to the negative output terminal. The capacitor is provided anywhere on the path from the connection point between the second end of the secondary winding and the first rectifier circuit and the second rectifier circuit, through the secondary winding, to ground.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the configuration of the related art described above, when generating discharge with a discharge electrode, it is necessary to use a transformer having a boosting ability corresponding to the high voltage required, and the degree of freedom in designing the transformer is low. For example, it may hinder the miniaturization of the transformer.

[0006] An object of the present invention is to provide a voltage generation circuit and a discharge device that can easily increase the degree of freedom in designing a transformer.

Means for Solving the Problems

[0007] A voltage generation circuit according to one aspect of the present invention includes a transformer, a first output terminal, and a first pulse addition circuit. The transformer has a primary winding and a secondary winding. The first output terminal is electrically connected to a first end of the secondary winding via a first rectifying element. The first pulse addition circuit electrically connects the first output terminal to a second end of the secondary winding via a first capacitive component.

[0008] A voltage generation circuit according to another aspect of the present invention includes a transformer, a first output terminal, and a first pulse addition circuit. The transformer has a primary winding and a secondary winding. A base voltage obtained by rectifying the output voltage from the secondary winding is applied to the first output terminal. The first pulse addition circuit superimposes a high-frequency component output from the secondary winding on the base voltage and applies it to the first output terminal.

[0009] A discharge device according to one aspect of the present invention includes the voltage generation circuit and the discharge electrode.

Effects of the Invention

[0010] According to the present invention, it is possible to provide a voltage generation circuit and a discharge device that can easily increase the degree of freedom in designing a transformer.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

[0012] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The following embodiments are examples embodying the present invention and are not intended to limit the technical scope of the present invention.

[0013] (Embodiment 1) [1] Overall Configuration First, the overall configuration of the discharge device 10 according to the present embodiment will be described with reference to FIGS. 1 and 2.

[0014] The discharge device 10 includes a voltage generation circuit 1 (see FIG. 2) and discharge electrodes 5. In the present embodiment, the discharge electrodes 5 include a first discharge electrode 51 and a second discharge electrode 52. The discharge device 10 according to the present embodiment includes induction electrodes in addition to the first discharge electrode 51 and the second discharge electrode 52.

[0015] The voltage generation circuit 1 is configured to be able to apply a voltage (high voltage) between the discharge electrodes 5 (the first discharge electrode 51 and the second discharge electrode 52) and the induction electrodes. In the discharge device 10, a voltage is applied to the discharge electrodes 5 (the first discharge electrode 51 and the second discharge electrode 52), and discharge occurs between the discharge electrodes 5 and the induction electrodes, thereby generating positive ions and negative ions as discharge products.

[0016] In this embodiment, as an example, the discharge device 10 is installed at a position facing an air passage through which the airflow (wind) generated by an airflow generating device such as a fan passes, and is arranged so that at least the first discharge electrode 51 and the second discharge electrode 52 are exposed in the air passage. Thereby, the discharge products (positive ions and negative ions) generated by the discharge device 10 ride on the airflow passing through the air passage and are discharged from the air outlet to a desired space (such as a room).

[0017] As shown in FIG. 1, the discharge device 10 according to this embodiment includes, in addition to the first discharge electrode 51 and the second discharge electrode 52, an electrode substrate 54, a case 55, an electrode protection part 56, a partition 57, and the like.

[0018] The case 55 is formed of a resin having electrical insulation properties, and is, for example, in the shape of a rectangular parallelepiped (box shape) having a length in one direction (the vertical direction in FIG. 1). The case 55 houses the electrode substrate 54, a circuit board, and the like inside. On one surface of the case 55, holes are formed for exposing at least the first discharge electrode 51 and the second discharge electrode 52.

[0019] On the electrode substrate 54, the first discharge electrode 51 and the second discharge electrode 52 are provided so as to protrude in the normal direction from one surface of the electrode substrate 54. In this embodiment, as an example, the first discharge electrode 51 and the second discharge electrode 52 are electrodes having a brush-shaped tip. These first discharge electrode 51 and second discharge electrode 52 protrude from one surface of the electrode substrate 54 at the same height position and are arranged side by side in one direction (the longitudinal direction of the case 55) with a space therebetween.

[0020] In addition, around the first discharge electrode 51 and the second discharge electrode 52 on one surface of the electrode substrate 54, induction electrodes electrically insulated from the first discharge electrode 51 and the second discharge electrode 52 are provided.

[0021] The circuit board housed in case 55 has a voltage generation circuit 1. An electrode substrate 54 is electrically connected to the circuit board on which the voltage generation circuit 1 is formed. Thereby, the voltage generation circuit 1 is electrically connected to the first discharge electrode 51 and the second discharge electrode 52 mounted on the electrode substrate 54. Thus, the voltage generated by the voltage generation circuit 1 is supplied to the first discharge electrode 51 and the second discharge electrode 52 of the electrode substrate 54, as well as to the induction electrode.

[0022] In this embodiment, the voltage generation circuit 1 generates positive and negative high voltages (high pressures), and by applying them to the discharge electrodes 5 (the first discharge electrode 51 and the second discharge electrode 52), discharges are generated at the discharge electrodes 5. The "high voltage (high pressure)" referred to in the present disclosure is a voltage of such a magnitude that discharges can be generated at the discharge electrodes 5 when applied thereto, and is, for example, a voltage of about several kV (8 kV as an example) in peak-to-peak.

[0023] Specifically, the voltage generation circuit 1 applies a pulse of positive high voltage (a voltage of + several kV as an example) to the first discharge electrode 51, and applies a pulse of negative high voltage (a voltage of - several kV as an example) to the second discharge electrode 52. That is, the first discharge electrode 51 is an example of a positive-side discharge electrode, and the second discharge electrode 52 is an example of a negative-side discharge electrode.

[0024] In this way, the voltage generation circuit 1 applies a voltage of such a magnitude as to generate a discharge between the induction electrode and the first discharge electrode 51 and the second discharge electrode 52 to the discharge electrodes 5. Here, positive ions are generated as discharge products from the first discharge electrode 51 which is the positive-side discharge electrode, and negative ions are generated as discharge products from the second discharge electrode 52 which is the negative-side discharge electrode.

[0025] In particular, in this embodiment, as shown in FIG. 2, the voltage generation circuit 1 includes a pulse application unit 2 and a booster circuit 3.

[0026] The pulse application unit 2 is electrically connected to the input connector 4. The pulse application unit 2 receives a supply of direct current voltage (from the input connector 4) and applies (outputs) a pulsed (impulse) voltage to the booster circuit 3.

[0027] The booster circuit 3 is electrically connected to the pulse application unit 2. The booster circuit 3 boosts the pulsed voltage applied from the pulse application unit 2 and applies (outputs) the boosted high-voltage pulse to the discharge electrode 5. That is, the booster circuit 3 is also electrically connected to the discharge electrodes 5 (the first discharge electrode 51 and the second discharge electrode 52), applies a positive voltage V1 to the first discharge electrode 51, and applies a negative voltage V2 to the second discharge electrode 52.

[0028] The electrode protection part 56 is disposed around the first discharge electrode 51 and the second discharge electrode 52. In the present embodiment, the electrode protection part 56 is integrally formed with the case 55 and protrudes in the same direction as the first discharge electrode 51 and the second discharge electrode 52 from the electrode holding surface 53. The height of the electrode protection part 56 is higher than the height of the tips of the first discharge electrode 51 and the second discharge electrode 52.

[0029] The electrode protection part 56 is composed of a pair of frame-shaped members located on both sides in the width direction of the case 55 with respect to each of the first discharge electrode 51 and the second discharge electrode 52. Specifically, the electrode protection part 56 is composed of a hollow frame body such that each of the first discharge electrode 51 and the second discharge electrode 52 is located inside thereof. However, the shape of the electrode protection part 56 is not limited to the shape shown in FIG. 1.

[0030] The partition wall 57 is formed of a resin having electrical insulation properties. The partition wall 57 is provided between the first discharge electrode 51 and the second discharge electrode 52 in the direction in which the first discharge electrode 51 and the second discharge electrode 52 are arranged (the longitudinal direction of the case 55 in the present embodiment) so as to partition the space between the first discharge electrode 51 and the second discharge electrode 52. In the present embodiment, the partition wall 57 is integrally formed with the case 55 and protrudes in the same direction as the first discharge electrode 51 and the second discharge electrode 52 from the electrode holding surface 53. The height of the partition wall 57 is higher than the height of the tips of the first discharge electrode 51 and the second discharge electrode 52.

[0031] The discharge device 10 is removably attached to the main body of an electric device such as an air cleaner, a heating device, or a cooling device. That is, the discharge device 10 and the main body of the electric device are separate bodies, and the main body of the electric device holds the discharge device 10 in a removable state. Therefore, for example, by removing the discharge device 10 from the main body of the electric device, it becomes easier to perform maintenance (including inspection, replacement, and repair, etc.) of the discharge device 10.

[0032] Further, in the present embodiment, the discharge device 10 has an input connector 4 electrically connected to a voltage generation circuit 1 or the like on a circuit board. The input connector 4 is disposed at one end in the longitudinal direction of the case 55 (the lower end in the example of FIG. 1). The input connector 4 is removably coupled to a mating connector held by the main body of the electric device.

[0033] When the input connector 4 and the mating connector are coupled, the input connector 4 and the mating connector are electrically connected, and the discharge device 10 is electrically connected to the main body of the electric device. In the present embodiment, as an example, the input connector 4 and the mating connector are plug-in connectors that can be attached and detached along the longitudinal direction of the case 55. Therefore, by sliding the case 55 along the longitudinal direction of the case 55 from a position where the input connector 4 faces the mating connector, it is possible to couple (electrically connect) the input connector 4 and the mating connector.

[0034] [2] Specific Configuration of Voltage Generation Circuit Next, the specific configuration of the voltage generation circuit 1 according to the present embodiment will be described with reference to FIG. 3.

[0035] In the present embodiment, as shown in FIG. 3, the boosting circuit 3 of the voltage generation circuit 1 includes a transformer 6, a first rectifying element D1, a first pulse addition circuit 71, a second rectifying element D2, a second pulse addition circuit 72, a first output terminal 81, and a second output terminal 82.

[0036] Transformer 6 has a primary winding 61 and a secondary winding 62. The primary winding 61 and the secondary winding 62 of the transformer 6 are magnetically coupled. When a current flows through the primary winding 61 and a magnetic flux is generated, an induced electromotive force is generated in the secondary winding 62. In this embodiment, the transformer 6 boosts the voltage applied to the primary winding 61 and generates a boosted voltage V0 between both ends (the first end 621 and the second end 622) of the secondary winding 62.

[0037] The primary winding 61 is electrically connected to the output of the pulse application unit 2. That is, the voltage generation circuit 1 according to this embodiment has a pulse application unit 2 that applies a pulse to the primary winding 61. Thereby, it is possible to generate a relatively large (high-voltage) voltage V0 in the secondary winding 62 by the induced electromotive force while inputting relatively small electrical energy to the primary winding 61.

[0038] The pulse application unit 2 receives a supply of a DC voltage from the main body of the electrical device via the input connector 4 and applies a pulse voltage to the primary winding 61. In this embodiment, a pulse voltage is applied to the primary winding 61 of the transformer 6 at a predetermined interval (for example, 100 Hz or more and 300 Hz or less).

[0039] The secondary winding 62 has a first end 621 and a second end 622. The first end 621, which is one end of the secondary winding 62, is electrically connected to the first output terminal 81 via the first rectifying element D1. The second end 622, which is the other end of the secondary winding 62, is electrically connected to the second output terminal 82 via the second rectifying element D2.

[0040] In this embodiment, as an example, the first rectifying element D1 is a diode that connects the anode to the first end 621 of the secondary winding 62 and the cathode to the first output terminal 81. That is, the first rectifying element D1 allows the current from the first end 621 of the secondary winding 62 to the first output terminal 81 to pass through by its rectifying action, while blocking the current (reverse current) in the opposite direction (from the first output terminal 81 to the first end 621 of the secondary winding 62).

[0041] Also, in this embodiment, as an example, the second rectifying element D2 is a diode having a cathode connected to the second end 622 of the secondary winding 62 and an anode connected to the second output terminal 82. That is, the second rectifying element D2 allows current to flow from the second output terminal 82 toward the second end 622 of the secondary winding 62 due to its rectifying action, while blocking current (reverse current) in the opposite direction (from the second end 622 of the secondary winding 62 toward the second output terminal 82).

[0042] The first pulse adding circuit 71 electrically connects the first output terminal 81 to the second end 622 of the secondary winding 62 via the first capacitance component C1. That is, the first pulse adding circuit 71 includes the first capacitance component C1 and forms a bypass path between the second end 622 of the secondary winding 62 and the first output terminal 81 through the first capacitance component C1.

[0043] In this embodiment, as an example, the first capacitance component C1 is a capacitor having a predetermined capacitance. The first capacitance component C1 is electrically connected between the connection point of the cathode of the second rectifying element D2 and the second end 622 of the secondary winding 62 and the connection point of the cathode of the first rectifying element D1 and the first output terminal 81. Thereby, a series circuit of the first rectifying element D1 and the first capacitance component C1 is electrically connected between the first end 621 and the second end 622 of the secondary winding 62 with the first rectifying element D1 on the first end 621 side.

[0044] The second pulse adding circuit 72 electrically connects the second output terminal 82 to the first end 621 of the secondary winding 62 via the second capacitance component C2. That is, the second pulse adding circuit 72 includes the second capacitance component C2 and forms a bypass path between the first end 621 of the secondary winding 62 and the second output terminal 82 through the second capacitance component C2.

[0045] In this embodiment, as an example, the second capacitance component C2 is a capacitor having a predetermined capacitance. The second capacitance component C2 is electrically connected between the connection point of the anode of the second rectifying element D2 and the second output terminal 82, and the connection point of the anode of the first rectifying element D1 and the first end 621 of the secondary winding 62. As a result, a series circuit of the second capacitance component C2 and the second rectifying element D2 is electrically connected between the first end 621 and the second end 622 of the secondary winding 62, with the second capacitance component C2 on the first end 621 side.

[0046] Here, in this embodiment, the first capacitance component C1 and the second capacitance component C2 have the same capacitance value (capacitance value). That is, the first pulse addition circuit 71 and the second pulse addition circuit 72 have capacitors with the same capacitance value. The "same capacitance value" as used in the present disclosure includes not only the case where the capacitance values completely match, but also the case where they approximately match with an error of several percent.

[0047] The first output terminal 81 and the second output terminal 82 constitute the output terminals of the voltage generation circuit 1. The "terminals" such as the first output terminal 81 and the second output terminal 82 as used in the present disclosure do not have to be terminal components for connecting electric wires or the like, and may be, for example, leads of electronic components or a part of a conductor included in a circuit board.

[0048] Specifically, the first output terminal 81 is electrically connected to the first discharge electrode 51 which is the positive-side discharge electrode, and the voltage generation circuit 1 applies a positive voltage V1 from the first output terminal 81 to the first discharge electrode 51. That is, the voltage generation circuit 1 generates a positive high-voltage V1 at the first output terminal 81.

[0049] On the other hand, the second output terminal 82 is electrically connected to the second discharge electrode 52 which is the negative-side discharge electrode, and the voltage generation circuit 1 applies a negative voltage V2 from the second output terminal 82 to the second discharge electrode 52. That is, the voltage generation circuit 1 generates a negative high-voltage V2 at the second output terminal 82.

[0050] The first output terminal 81 is electrically connected to the first end 621 of the secondary winding 62 via a first rectifying element D1. Here, the first output terminal 81 is connected to the cathode of the first rectifying element D1.

[0051] Also, the second output terminal 82 is electrically connected to the second end 622 of the secondary winding 62 via a second rectifying element D2. Here, the second output terminal 82 is connected to the anode of the second rectifying element D2.

[0052] [3] Operating example of the voltage generation circuit Next, an operating example of the voltage generation circuit 1 according to the present embodiment will be described with reference to FIGS. 4 to 6.

[0053] In FIG. 4, the current path for "positive voltage output" that outputs a positive voltage V1 from the first output terminal 81 is shown in the upper stage, and the current path for "negative voltage output" that outputs a negative voltage V2 from the second output terminal 82 is shown in the lower stage.

[0054] That is, when the pulse application unit 2 applies a pulse voltage to the primary winding 61 of the transformer 6 in the boost circuit 3, currents I11, I12, I21, I22 flow from the secondary winding 62 of the transformer 6 as shown in FIG. 4. In FIG. 4, the paths of the currents I11, I12, I21, I22 with the induced electromotive force generated in the secondary winding 62 as the current source are indicated by thick dashed arrows.

[0055] Here, the current for positive voltage output includes the currents I11 and I12 as shown in the upper stage of FIG. 4. That is, due to the currents I11 and I12, a positive voltage V1 is output from the first output terminal 81.

[0056] The current I11 is a current that flows from the first end 621 of the secondary winding 62, passes through the first rectifying element D1 and the first capacitive component C1 (first pulse addition circuit 71) in this order, and flows to the second end 622 of the secondary winding 62. According to the current I11, the first capacitive component C1 is charged with a DC voltage (base voltage) obtained by rectifying the output voltage from the secondary winding 62 by the first rectifying element D1. Specifically, the first capacitive component C1 accumulates charges with the upstream side of the current I11 (that is, the first output terminal 81 side) being at a high potential by the current I11.

[0057] The current I12 is a current that flows from the second end 622 of the secondary winding 62, passes through the first capacitive component C1 (first pulse addition circuit 71), and flows to the first output terminal 81. That is, since the first capacitive component C1 allows the high-frequency component output from the secondary winding 62 to pass through, according to the current I12, a high-frequency component of the output voltage from the secondary winding 62 is applied to the first output terminal 81. The "high-frequency component" here means a frequency component higher than the cut-off frequency specific to the first capacitive component C1, and is a frequency component that can pass through the first capacitive component C1 with low impedance.

[0058] On the other hand, the current for negative voltage output includes currents I21 and I22 as shown in the lower part of FIG. 4. That is, due to the currents I21 and I22, a negative voltage V2 is output from the second output terminal 82.

[0059] The current I21 is a current that flows from the first end 621 of the secondary winding 62, passes through the second capacitive component C2 (second pulse addition circuit 72) and the second rectifying element D2 in this order, and flows to the second end 622 of the secondary winding 62. According to the current I21, the second capacitive component C2 is charged with a DC voltage (base voltage) obtained by rectifying the output voltage from the secondary winding 62 by the second rectifying element D2. Specifically, the second capacitive component C2 accumulates charges with the downstream side of the current I21 (that is, the second output terminal 82 side) being at a low potential by the current I21.

[0060] The current I22 is a current that flows from the second output terminal 82, through the second capacitance component C2 (the second pulse addition circuit 72), to the first end 621 of the secondary winding 62. That is, since the second capacitance component C2 allows the high-frequency components output from the secondary winding 62 to pass through, according to the current I22, a high-frequency component of the output voltage from the secondary winding 62 is applied to the second output terminal 82. The "high-frequency component" mentioned here means a frequency component higher than the cut-off frequency specific to the second capacitance component C2, and is a frequency component that can pass through the second capacitance component C2 with low impedance.

[0061] As a result, as shown in FIG. 5, the voltage generation circuit 1 can generate voltages V1 and V2, which are further boosted, at the first output terminal 81 and the second output terminal 82 with respect to the voltage V0 generated between both ends of the secondary winding 62 of the transformer 6. In FIG. 5, the time axis is the horizontal axis, and waveform diagrams of the voltages V0, V1, and V2 with simplified waveforms are shown.

[0062] That is, as shown in the upper part of FIG. 5, when the voltage V0 is generated between both ends of the secondary winding 62 of the transformer 6, the first capacitance component C1 is charged with the first output terminal 81 side at a high potential by the current I11 described above. Therefore, the positive base voltage (+Vb1), which is the voltage across the charged first capacitance component C1, is applied to the first output terminal 81. Further, by the current I12 described above, a high-frequency component of the output voltage from the secondary winding 62 is applied to the first output terminal 81 in a form superimposed on the positive base voltage (+Vb1).

[0063] Therefore, as shown in the lower part of FIG. 5, the voltage generation circuit 1 generates a voltage V1, in which a high-frequency component corresponding to the voltage V0 is superimposed, at the first output terminal 81 with respect to the positive base voltage (+Vb1). Thus, the voltage generation circuit 1 can apply a positive high-voltage voltage V1 from the first output terminal 81 to the first discharge electrode 51.

[0064] Similarly, as shown in the upper part of FIG. 5, when a voltage V0 is generated between both ends of the secondary winding 62 of the transformer 6, the second capacitance component C2 is charged with the second output terminal 82 side at a low potential by the current I21 described above. Therefore, the negative base voltage (-Vb1), which is the voltage across the charged second capacitance component C2, is applied to the second output terminal 82. Further, due to the current I22 described above, a high-frequency component of the output voltage from the secondary winding 62 is applied to the second output terminal 82 in a form superimposed on the negative base voltage (-Vb1).

[0065] Therefore, as shown in the lower part of FIG. 5, the voltage generation circuit 1 generates a voltage V2 in which a high-frequency component corresponding to the voltage V0 is superimposed on the negative base voltage (-Vb1) at the second output terminal 82. Thus, the voltage generation circuit 1 can apply a negative high-voltage voltage V2 from the second output terminal 82 to the second discharge electrode 52.

[0066] By the way, as a related art of this type of voltage generation circuit 1, a voltage generation circuit including a transformer, a first rectifier circuit, a second rectifier circuit, and a capacitor can be considered. The transformer has a primary winding to which an AC voltage is input and a secondary winding with its first end connected to ground. The first rectifier circuit has a first diode with its anode connected to the second end of the secondary winding of the transformer and its cathode connected to the positive output terminal. The second rectifier circuit has a second diode connected to the second end of the secondary winding, with its cathode connected to the second end and its anode connected to the negative output terminal. The capacitor is provided anywhere on the path from the connection point between the second end of the secondary winding and the first and second rectifier circuits, through the secondary winding, to ground.

[0067] In the configuration of the above related art (hereinafter referred to as a comparative example), it is necessary to use a transformer having a boosting ability corresponding to the high voltage required to generate discharge at the discharge electrode 5, and the design freedom of the transformer is low. For example, it may hinder the miniaturization of the transformer.

[0068] In contrast, according to the voltage generation circuit 1 according to the present embodiment, it is possible to provide the voltage generation circuit 1 and the discharge device 10 that are likely to increase the design freedom of the transformer 6.

[0069] FIG. 6 is a waveform diagram showing voltages V1 and V2 generated at the first output terminal 81 and the second output terminal 82 with respect to the voltage V0 generated between both ends of the secondary winding 62 of the transformer 6 in a voltage generation circuit according to a comparative example adopting the configuration of the related art.

[0070] That is, as shown in FIG. 6, in the comparative example, the voltage V1 applied to the first output terminal 81 is only the positive base voltage (+Vb1), which is the voltage across the charged first capacitance component C1. Similarly, the voltage V2 applied to the second output terminal 82 is only the negative base voltage (-Vb1), which is the voltage across the charged second capacitance component C2. Thus, in the comparative example, since the voltage cannot be boosted beyond the boosting ability of the transformer 6, it is necessary to use a transformer 6 having a boosting ability corresponding to the high voltage required to generate a discharge at the discharge electrode 5. Therefore, in the comparative example, the design freedom of the transformer 6 is low, and for example, it may hinder the miniaturization of the transformer 6.

[0071] In contrast, according to the voltage generation circuit 1 according to the present embodiment, as shown by the imaginary line (two-dot chain line) in FIG. 6, the voltage V1 applied to the first output terminal 81 becomes a voltage in which a high-frequency component is superimposed on the positive base voltage (+Vb1). Similarly, the voltage V2 applied to the second output terminal 82 becomes a voltage in which a high-frequency component is superimposed on the negative base voltage (-Vb1).

[0072] Therefore, in the voltage generation circuit 1 according to the present embodiment, the voltages V1 and V2 output from the first output terminal 81 and the second output terminal 82 can be further boosted by the amount of high-frequency components compared to the comparative example. As a result, the voltage applied from the voltage generation circuit 1 to the discharge electrodes 5 (the first discharge electrode 51 and the second discharge electrode 52) can be boosted beyond the boosting ability of the transformer 6. Therefore, according to the present embodiment, it is possible to efficiently output a (positive and negative) high voltage, and it is easy to increase the design freedom of the transformer 6. For example, by reducing the output voltage itself of the transformer 6, such as reducing the boosting ability of the transformer 6, the transformer 6 can be miniaturized.

[0073] As described above, the voltage generation circuit 1 according to the present embodiment includes a first output terminal 81 and a first pulse addition circuit 71. The first output terminal 81 is electrically connected to the first end 621 of the secondary winding 62 via a first rectifying element D1. The first pulse addition circuit 71 electrically connects the first output terminal 81 to the second end 622 of the secondary winding 62 via a first capacitance component C1.

[0074] Thereby, the high-frequency component from the second end 622 of the secondary winding 62 can be superimposed on the voltage V1 output from at least the first output terminal 81 via the first capacitance component C1, so that the voltage V1 output from the first output terminal 81 can be boosted beyond the boosting ability of the transformer 6. Therefore, there is an advantage that it is easy to increase the design freedom of the transformer 6.

[0075] Here, in the present embodiment, the first capacitance component C1 has a power storage function of storing the charge output from the secondary winding 62 and a high-pass function of passing the high-frequency component output from the secondary winding 62. That is, while using the first capacitance component C1 as a power storage unit for applying a base voltage (+Vb1) to the first output terminal 81, it can also be used as a high-pass filter for superimposing high-frequency components, thereby simplifying the circuit.

[0076] Further, the voltage generation circuit 1 according to the present embodiment further includes a second output terminal 82 and a second pulse addition circuit 72. The second output terminal 82 is electrically connected to the second end 622 of the secondary winding 62 via a second rectifying element D2. The second pulse addition circuit 72 electrically connects the second output terminal 82 to the first end 621 of the secondary winding 62 via a second capacitance component C2.

[0077] As a result, not only the voltage V1 output from the first output terminal 81 but also the voltage V2 output from the second output terminal 82 can have a high-frequency component from the first end 621 of the secondary winding 62 superimposed thereon via the second capacitance component C2. Therefore, the voltage V2 output from the second output terminal 82 can be boosted beyond the boosting capacity of the transformer 6. Thus, there is an advantage that it is easy to increase the design freedom of the transformer 6.

[0078] Here, in the present embodiment, the second capacitance component C2 has a power storage function of storing the charge output from the secondary winding 62 and a high-pass function of passing the high-frequency component output from the secondary winding 62. That is, while using the second capacitance component C2 as a power storage unit for applying a base voltage (-Vb1) to the second output terminal 82, it can also be used as a high-pass filter for superimposing a high-frequency component, thereby simplifying the circuit.

[0079] Moreover, in the present embodiment, as described above, the first capacitance component C1 and the second capacitance component C2 have the same capacitance value. Therefore, the voltages V1 and V2 can be output in a well-balanced manner from both the first output terminal 81 and the second output terminal 82.

[0080] And the first output terminal 81 (and the second output terminal 82) is electrically connected to the discharge electrode 5. Therefore, the voltage generation circuit 1 contributes to efficiently generating a discharge with a highly boosted voltage and efficiently generating discharge products (positive ions and negative ions).

[0081] That is, the voltage generation circuit 1 according to this embodiment includes a transformer 6, a first output terminal 81, and a first pulse addition circuit 71. The transformer 6 has a primary winding 61 and a secondary winding 62. The first output terminal 81 is applied with a base voltage (+Vb1) obtained by rectifying the output voltage from the secondary winding 62. The first pulse addition circuit 71 superimposes the high-frequency component output from the secondary winding 62 on the base voltage (+Vb1) and applies it to the first output terminal 81.

[0082] Thus, the voltage generation circuit 1 may have a configuration in which the base voltage obtained by rectifying the output voltage from the secondary winding 62 is applied to the first output terminal 81, and the high-frequency component output from the secondary winding 62 is superimposed on the base voltage by the first pulse addition circuit 71. Therefore, for example, the first rectifying element D1 and the first capacitive component C1 are merely an example for embodying the voltage generation circuit 1 and are not essential components.

[0083] The same applies to the second output terminal 82 and the second pulse addition circuit 72. The second rectifying element D2 and the second capacitive component C2 are merely an example for embodying the voltage generation circuit 1 and are not essential components.

[0084] [4] Modification Hereinafter, modifications of Embodiment 1 will be listed. The modifications described below can be applied in appropriate combinations.

[0085] The specific configuration of the voltage generation circuit 1 is not limited to the configuration shown in FIG. 3 and can be appropriately changed as long as the same function can be realized. For example, the first capacitive component C1 and / or the second capacitive component C2 are not limited to capacitors and may be realized by, for example, parasitic capacitance or the like. Similarly, the first rectifying element D1 and / or the second rectifying element D2 are not limited to diodes and may be realized by, for example, parasitic diodes (body diodes) or the like.

[0086] In Embodiment 1, in addition to the first output terminal 81, a voltage generation circuit 1 including a second output terminal 82 that outputs positive and negative voltages V1 and V2 was exemplified. However, the present invention is not limited to this, and the second output terminal 82 may be omitted as appropriate. In this case, the voltage output from the first output terminal 81 is not limited to a positive voltage, and may be a negative voltage.

[0087] In addition, it is not essential for the discharge device 10 to generate positive and negative ions. For example, discharge products other than ions may be generated by the discharge between the first discharge electrode 51 and the second discharge electrode 52. Further, it is not essential for the discharge device 10 to have an induction electrode.

[0088] In the discharge device 10, each of the first discharge electrode 51 and the second discharge electrode 52 has one, but may have a plurality of them. The shapes of the first discharge electrode 51 and the second discharge electrode 52 are not limited to a brush shape, and may be, for example, a pin shape (needle shape) or the like.

[0089] [Supplementary Note of the Invention] Hereinafter, the outline of the invention extracted from the above-described embodiments will be appended. Note that each configuration and each processing function described in the following supplementary note can be arbitrarily combined by selection.

[0090] <Supplementary Note 1> A transformer having a primary winding and a secondary winding, A first output terminal electrically connected to a first end of the secondary winding via a first rectifying element, A first pulse addition circuit that electrically connects the first output terminal to a second end of the secondary winding via a first capacitance component, A voltage generation circuit.

[0091] <Supplementary Note 2> The first capacitance component has a power storage function of storing charges output from the secondary winding and a high-pass function of passing high-frequency components output from the secondary winding. The voltage generation circuit according to Supplementary Note 1.

[0092] <Supplementary Note 3> A second output terminal electrically connected to the second end of the secondary winding via a second rectifying element; A second pulse adding circuit for electrically connecting the second output terminal to the first end of the secondary winding via a second capacitance component; and further comprising. The voltage generation circuit according to appended note 1 or 2.

[0093] <Appended note 4> The second capacitance component has a power storage function of storing the charge output from the secondary winding and a high-pass function of passing the AC component output from the secondary winding. The voltage generation circuit according to appended note 3.

[0094] <Appended note 5> The first capacitance component and the second capacitance component have the same capacitance value. The voltage generation circuit according to appended note 3 or 4.

[0095] <Appended note 6> The first output terminal is electrically connected to the discharge electrode. The voltage generation circuit according to any one of appended notes 1 to 5.

[0096] <Appended note 7> Further having a pulse applying unit for applying a pulse to the primary winding. The voltage generation circuit according to any one of appended notes 1 to 6.

[0097] <Appended note 8> A transformer having a primary winding and a secondary winding; A first output terminal to which a base voltage formed by rectifying the output voltage from the secondary winding is applied; A first pulse adding circuit for superimposing a high-frequency component output from the secondary winding on the base voltage and applying the same to the first output terminal; and comprising. Voltage generation circuit.

[0098] <Appended note 9> The voltage generation circuit according to any one of appended notes 1 to 8; and A discharge electrode; and comprising. Discharge device.

Description of Symbols

[0099] 1 Voltage generation circuit 2 Pulse application section 5 Discharge electrode 6 Transformer 10 Discharge device 61 Primary winding 62 Secondary winding 71 First pulse addition circuit 72 Second pulse addition circuit 81 First output terminal 82 Second output terminal 621 First end 622 Second end C1 First capacitance component C2 Second capacitance component D1 First rectifying element D2 Second rectifying element

Claims

1. A transformer having a primary winding and a secondary winding, A first output terminal electrically connected to a first end of the secondary winding via a first rectifying element, A first pulse addition circuit that electrically connects the first output terminal to a second end of the secondary winding via a first capacitance component, A voltage generation circuit.

2. The first capacitance component has a power storage function of storing charges output from the secondary winding and a high-pass function of passing high-frequency components output from the secondary winding, The voltage generation circuit according to claim 1.

3. A second output terminal electrically connected to the second end of the secondary winding via a second rectifying element, A second pulse addition circuit that electrically connects the second output terminal to the first end of the secondary winding via a second capacitance component, The voltage generation circuit according to claim 1 or 2.

4. The second capacitance component has a power storage function of storing charges output from the secondary winding and a high-pass function of passing AC components output from the secondary winding, The voltage generation circuit according to claim 3.

5. The first capacitance component and the second capacitance component have the same capacitance value, The voltage generation circuit according to claim 3.

6. The first output terminal is electrically connected to a discharge electrode, The voltage generation circuit according to claim 1 or 2.

7. Further comprising a pulse application unit that applies a pulse to the primary winding, The voltage generation circuit according to claim 1 or 2.

8. A transformer having a primary winding and a secondary winding, A first output terminal to which a base voltage obtained by rectifying the output voltage from the secondary winding is applied; A first pulse addition circuit that superimposes a high-frequency component output from the secondary winding on the base voltage and applies the result to the first output terminal; and A voltage generation circuit.

9. The voltage generation circuit according to claim 1 or 2; and A discharge electrode; and A discharge device.

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