JP2006156276A - Air nozzle type ion generation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air nozzle type ion generation device capable of restraining occurrence of dust caused by corona discharge in a passage of compressed air. <P>SOLUTION: A nozzle body 14 and a nozzle tip part 18 are formed of a nonmetal material, a counter electrode 3 is disposed in the outside of a part of the nozzle body 14 facing to a discharge needle 2 mounted in the nozzle body 14. Corona discharge is generated at the discharge needle 2 by applying a high-frequency high voltage stepped up by a piezoelectric transformer 28 in an A.C. high-voltage power source 4 between the discharge needle 2 and the counter electrode 3, and positive and negative air ions generated by the corona discharge are jetted from a nozzle opening 17 along with compressed air supplied from an air supply tube 16. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an air nozzle type ion generating apparatus that generates positive and negative air ions suitable for neutralizing static electricity of a charged body by generating corona discharge in the air and ejecting the air ions together with compressed air. About.

  2. Description of the Related Art Conventionally, an air nozzle type ion generator that ejects positive and negative air ions together with compressed air is known (see, for example, Patent Document 1). FIG. 5 is an external view of a conventional air nozzle ion generator, and FIG. 6 is a longitudinal sectional view of the air nozzle ion generator shown in FIG.

  Referring to FIGS. 5 and 6, a conventional air nozzle type ion generating apparatus 100 has a cylindrical shape and is provided with a nozzle body in which an air passage 113 penetrates in the axial direction and a discharge needle 110 is implanted. 101, a counter electrode 111 provided circumferentially at the outlet of the air passage 113, and a power supply case 104 fixed on the lower surface of the nozzle body 101 and incorporating an AC high-voltage power supply 112.

  An air supply pipe 105 connected to an air supply device (not shown) is attached to the inlet of the air passage 113 of the nozzle body 100. In addition, a metal nozzle cap 102 having a nozzle port 106 formed at the tip is attached to the outlet of the air passage 113, and the counter electrode 111 is sandwiched between the nozzle cap 102 and the nozzle body 101. . Therefore, the counter electrode 111 and the nozzle cap 102 come into contact and are electrically connected, and the nozzle cap 102 itself functions as a counter electrode.

  Further, the discharge needle 110 is in electrical contact with the metal electrode ring 121 soldered to the output cable 112a of the AC high voltage power source 112. On the other hand, the return cable 112 b of the AC high voltage power supply 112 is connected to the counter electrode 111. When a high frequency high voltage is applied between the discharge needle 110 and the counter electrode (the counter electrode 111 and the nozzle cap 102) via the output cable 112a and the return cable 112b by the AC high voltage power supply 112, the discharge needle 110 coronas the corona. Discharge occurs and positive and negative air ions are generated.

The positive and negative air ions generated in this way are ejected from the nozzle port 106 together with the compressed air supplied from the air supply pipe 105. In the process, positive and negative air ions and secondary ions are generated. Ozone is sprayed onto the metal nozzle cap 102 to come into contact. Then, due to such contact with air ions or ozone, a chemical reaction such as oxidation occurs on the surface of the nozzle cap 102 and the nozzle cap 102 corrodes, and dust generated by the corrosion is ejected from the nozzle port 106 together with the compressed air. There was an inconvenience.
JP 2002-208497 A

  An object of the present invention is to provide an air nozzle type ion generating apparatus that eliminates the above-mentioned disadvantages and suppresses the generation of dust due to corona discharge in a flow path of compressed air.

  The present invention has been made to achieve the above object, and includes a discharge needle provided in a nozzle to which compressed air is supplied, a counter electrode opposed to the discharge needle, the discharge needle and the counter electrode, An AC high voltage power source for applying an AC high voltage between the positive electrode and the corona discharge generated when a high voltage is applied between the discharge needle and the counter electrode by the AC high voltage power source. The present invention relates to an improvement in an air nozzle type ion generating apparatus that ejects negative air ions together with compressed air from the tip of a nozzle. And the said counter electrode is provided facing the said discharge needle through the nonmetallic member, It is characterized by the above-mentioned.

  According to the present invention, the discharge needle and the counter electrode are opposed to each other via the non-metallic member. Therefore, the non-metallic member prevents positive and negative air ions and ozone generated by corona discharge in the discharge needle from contacting the counter electrode, and contact with the air ions and ozone causes the counter electrode to Corrosion can be prevented from occurring. And it can prevent that the dust produced by the corrosion of the said counter electrode is ejected from the front-end | tip of a nozzle with compressed air by this.

  A portion of the nozzle facing the discharge needle is formed of a non-metallic material as the non-metallic member, and the counter electrode is disposed outside the portion of the nozzle formed of the non-metallic material via the portion. It is provided facing the discharge needle.

  According to the present invention, the portion of the nozzle itself facing the discharge needle is formed of a non-metallic material, and the counter electrode is provided outside the portion formed of the non-metallic material. A configuration in which the electrodes are provided to face each other with the non-metal member interposed therebetween can be easily realized without providing an additional member.

  The AC high-voltage power supply applies a high-frequency AC high voltage generated by a high-frequency transformer between the discharge needle and the counter electrode.

  According to the present invention, by applying a high-frequency AC high voltage between the discharge needle and the counter electrode, the AC impedance of the non-metallic member when the AC high voltage is applied is reduced, The amount of current from the discharge needle to the counter electrode can be increased. And thereby, the corona discharge in the said discharge needle | hook can be accelerated | stimulated and the production amount of positive and negative air ion can be increased.

  In addition, by using a piezoelectric transformer as the high-frequency transformer, the AC high-voltage power supply can be downsized compared to the case of using a winding transformer, so that the nozzle and AC high-voltage power supply can be easily integrated. can do.

  Embodiments of the present invention will be described with reference to FIGS. FIG. 1 is an overall configuration diagram of an air nozzle type ion generator of the present invention, FIG. 2 is an external perspective view of the air nozzle type ion generator shown in FIG. 1, and FIG. 3 is an air nozzle type ion generator shown in FIG. FIG. 4 is a block diagram of a test apparatus for the air nozzle type ion generator shown in FIG.

  Referring to FIG. 1, an air nozzle type ion generator 1 (hereinafter referred to as ion generator 1) includes a nozzle including a nozzle body 14 and a nozzle tip 18, and an AC high voltage power source 4. The output cable 4 a is connected to the discharge needle 2 provided in the nozzle body 14, and the return cable 4 b is connected to the counter electrode 3 arranged outside the nozzle body 14. Further, compressed air is supplied to the nozzle body 14 from the compressed air supply device 30 connected via the air supply pipe 16 and the air pipe 31 of the nozzle body 14.

  Next, referring to FIGS. 2 and 3, the nozzle (nozzle body 14 and nozzle tip 18) and the power supply case 15 housing the AC high-voltage power supply 4 are integrally connected. The nozzle body 14 and the nozzle tip 18 are integrally formed of an insulating nonmetal (plastic, ceramics, etc.).

  An air supply pipe 16 is screwed to the inlet of the air passage 13 of the nozzle body 14. The air passage 13 has a circular cross section, but the air passage 13b near the outlet from the middle to the outlet is larger in diameter than the air passage 13a near the inlet. The central axis of the air passage 13a close to the inlet is located above the central axis of the air passage 13b close to the enlarged outlet.

  The discharge needle 2 has a nozzle body 14 via a metal socket 19 so that its axis coincides with the central axis of the air passage 13b and the nozzle tip 18 and its tip is located at the center of the counter electrode 3. The screw hole 22 is screwed.

  An output cable 4 a of the AC high voltage power supply 4 provided in the power supply case 15 is covered with an insulating coating 20, fitted into a ring of a metal electrode ring 21, and soldered to the electrode ring 21. The output cable 4a and the electrode ring 21 are inserted into the nozzle body 14 in the direction orthogonal to the axis of the discharge needle 2 from the power supply case 15 side. At this time, the outer peripheral surface of the electrode ring 21 contacts the rear end of the discharge needle 2 and the socket 19 and is electrically connected.

  Further, the counter electrode 3 is disposed outside the portion (corresponding to the non-metal member of the present invention) facing the vicinity of the tip of the discharge needle 2 of the nozzle body 14. Therefore, the discharge needle 2 and the counter electrode 3 are in a state of facing each other through the nozzle body 14 formed of an insulating nonmetal. The counter electrode 3 is connected to the return cable 4b of the AC high voltage power supply 4 and grounded.

  The AC high-voltage power supply 4 includes a DC power supply 25 that generates a DC voltage from a commercial AC power supply, an oscillation circuit 26 that generates a high-frequency AC voltage when a DC voltage output from the DC power supply 25 is applied, and the high-frequency AC voltage as a piezoelectric ceramic. And a piezoelectric transformer 28 that outputs a high-frequency high voltage by being boosted by a piezoelectric element 27. Thus, by forming a booster circuit using the piezoelectric transformer 28, the AC high-voltage power supply 4 can be reduced in size and weight as compared with the case where the commercial AC power supply is directly boosted by the winding transformer. it can.

  When a high frequency high voltage is applied to the discharge needle 2 by the AC high voltage power source 4, an electric field is formed between the discharge needle 2 and the counter electrode 3, and a corona discharge is generated from the discharge needle 2 to generate positive and negative air ions. Is done. Then, compressed air supplied from the compressed air supply device 30 (see FIG. 1) to the air supply pipe 16 flows through the air passage 13, and compressed air containing positive and negative air ions is ejected from the nozzle port 17. .

  In this case, since the nozzle body 14 formed of an insulating non-metal is interposed between the discharge needle 2 and the counter electrode 3, the positive and negative air ions generated by the corona discharge and the secondary coronal discharge are generated by the corona discharge. The ozone generated next does not touch the counter electrode 3. Therefore, the counter electrode 3 is not corroded by a chemical reaction due to contact with positive and negative air ions or ozone, and the dust generated by the corrosion of the counter electrode 3 is ejected from the nozzle port 17, and the static elimination object and its object It is possible to prevent the vicinity from being contaminated.

  Next, the static elimination characteristic of the ion generator 1 demonstrated above is demonstrated. Referring to FIG. 4, the inventors of the present application conducted a test for examining the charge removal effect of ion generator 1 using charged plate monitor 40. The charging plate monitor 40 includes a metal plate 42 attached to a main body 41 via an insulating member 43, a surface potential measuring device 44 for measuring the potential of the metal plate 42 inside the main body 41, and a metal plate. A high voltage power supply 45 for applying a charge to the plate 42 and a timer 46 for measuring a change time of the potential of the metal plate 42 are provided.

  As a test method, the ion generating apparatus 1 is installed at a position separated by a distance L on the upper surface of the metal plate 42, and air containing positive and negative air ions ejected from the ion generating apparatus 1 is charged with the charged plate monitor 40. The metal plate 42 is sprayed. At this time, if the positive and negative air ions in the blown air are biased, charges are accumulated in the metal plate 42 and the absolute value of the voltage detected by the surface potential measuring device 44 is increased. Therefore, this voltage (referred to as offset voltage) is measured as an index of ion balance.

  Further, when the metal plate 42 is charged to ± 1,000 V by the high voltage power supply 45 and air containing positive and negative air ions ejected from the ion generator 1 is blown to neutralize static electricity. In addition, the time (attenuation time) required for the potential of the metal plate 42 to drop to ± 100 V is measured.

  The decay time and offset voltage were measured for the ion generator 1 of the present embodiment and the conventional ion generator 100 provided with the metallic nozzle cap 102 of FIGS. 5 and 6 described in the background art. The comparison results are shown in Table 1 below. The nozzle of the ion generating device 1 is made of ABS resin, and the nozzle cap 102 of the conventional ion generating device 100 is made of aluminum, both of which are AC high voltage (frequency: 68 kHz, output voltage 2 kV) by a piezoelectric transformer using piezoelectric ceramics. Was generated and applied between the discharge needle and the counter electrode.

  Both ion generators were tested with the pressure of the compressed air supplied from the compressed air supply device being 0.1 MPa and the distance L from the nozzle opening to the metallic plate 42 being 50 mm.

  From the test results shown in Table 1 above, it can be seen that even when the ion generator 1 of the present invention is used, the same level of effect as that of the conventional ion generator can be obtained, and there is no practical problem.

  In the present embodiment, the counter electrode 3 is arranged outside the nozzle body 14 formed of an insulating nonmetal. However, the embodiment of the present invention is not limited to this, and the discharge needle and the counter electrode are made of a nonmetal. The effect of this invention can be acquired by setting it as the structure made to oppose through a member. For example, a counter electrode may be embedded in the side wall of the nozzle body formed of a nonmetal so that the discharge needle and the counter electrode face each other via a nonmetal member.

  In the present embodiment, the high frequency AC voltage is applied between the discharge needle 2 and the counter electrode 3 to reduce the impedance when the current flows through the nozzle. However, the AC voltage of about the frequency of the commercial power supply is applied. Even in this case, the effect of the present invention can be obtained.

  In this embodiment, a piezoelectric transformer is used as the high-frequency transformer of the present invention. However, a high-frequency oscillation step-up transformer may be used. Also in this case, since the high voltage winding portion can be reduced in size, the AC high voltage power supply 4 can be reduced in size as compared with the case where a commercial frequency winding transformer is used.

BRIEF DESCRIPTION OF THE DRAWINGS The whole block diagram of the air nozzle type | mold ion generator of this invention. The external appearance perspective view of the air nozzle type | mold ion generator shown in FIG. The longitudinal cross-sectional view of the air nozzle type | mold ion generator shown in FIG. The block diagram of the test apparatus with respect to the air nozzle type | mold ion generator shown in FIG. The external perspective view of the conventional air nozzle type | mold ion generator. The longitudinal cross-sectional view of the conventional air nozzle type | mold ion generator.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Air nozzle type ion generator, 2 ... Discharge needle, 3 ... Counter electrode, 4 ... AC high voltage power supply, 4a ... Output cable, 4b ... Return cable, 13 ... Air passage, 14 ... Nozzle body, 18 ... Nozzle tip 25 ... DC power supply, 26 ... oscillation circuit, 28 ... piezoelectric transformer

Claims (4)

A discharge needle provided in a nozzle to which compressed air is supplied; a counter electrode facing the discharge needle; and an AC high-voltage power source for applying an AC high voltage between the discharge needle and the counter electrode The positive and negative air ions generated by the corona discharge generated when a high voltage is applied between the discharge needle and the counter electrode by the AC high-voltage power source are jetted together with the compressed air from the tip of the nozzle In the nozzle type ion generator,
The air nozzle type ion generating apparatus, wherein the counter electrode is provided to face the discharge needle through a non-metallic member.   A portion of the nozzle facing the discharge needle is formed of a nonmetallic material as the nonmetallic member, and the counter electrode is disposed outside the portion of the nozzle formed of the nonmetallic material via the portion. The air nozzle type ion generating apparatus according to claim 1, wherein the air nozzle type ion generating apparatus is provided to face the needle.   The air nozzle type ion generator according to claim 1 or 2, wherein the AC high voltage power source applies a high frequency AC high voltage generated by a high frequency transformer between the discharge needle and the counter electrode. .   The air nozzle ion generator according to claim 3, wherein the high-frequency transformer is a piezoelectric transformer.

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