JP2013218785A - Ion generator and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such a problem of a conventional ion generator that since a power supply unit is resin molded, operation is stable even if the humidity in the air is high, but when moisture adheres to the surface of mold resin, short circuit takes place between a needle electrode, exposed from the resin, and a power supply terminal to an annular electrode thus bringing about a state where ions are not generated.SOLUTION: A cylindrical body located on the inside of an annular electrode so as to surround a needle electrode is constituted so that the whole circumference at the end of the cylindrical body is buried in the mold resin and the cylindrical body is fixed, thus extending the creepage distance between the needle electrode and a power supply terminal to the annular electrode.

Description

  The present invention relates to an ion generation device that generates an ion by discharging between a needle electrode and an annular electrode surrounding the needle electrode, and a method of manufacturing the ion generation device.

  In this type of conventional ion generator, a power supply unit including a step-up transformer is housed in a bottomed casing that opens upward, and low voltage DC power supplied from outside is supplied with high voltage AC. It is known that the voltage is increased to electric power and applied between a pair of opposing discharge electrodes to be discharged. In this device, the boosted high-voltage AC power is supplied to the needle electrode and the annular electrode surrounding the needle electrode, and is discharged between both electrodes to generate ions.

  Since the power supply unit must be isolated from humidity in the external atmosphere to ensure stable operation, liquid resin such as urethane resin is poured into the casing with the power supply unit housed in the casing, and the power supply unit Resin mold processing is performed to cure the resin in a state where it is completely buried in the resin. In addition, since at least the tip portion of the needle electrode and the annular electrode are exposed to the air without being molded, the power supply terminal to the needle electrode and the annular electrode is exposed from the surface of the molded resin ( For example, see Patent Document 1).

JP 2010-266139 A (paragraph 0064, FIG. 5)

  In the conventional ion generator, for example, even if the humidity in the air increases, the power supply unit is molded with resin, so that the operation does not become unstable. If this occurs, a short circuit occurs due to creeping discharge between the needle-shaped electrode exposed from the resin and the power supply terminal to the annular electrode, and power is not supplied to the discharge electrode, resulting in a problem that ions are not generated. .

  Then, this invention makes it a subject to provide the ion generator with which it is hard to produce a short circuit between the acicular electrode and the electric power feeding terminal to an annular electrode, and its manufacturing method in view of said problem.

  In order to solve the above problems, an ion generator according to the present invention stores a power supply unit that generates a high voltage in a bottomed casing that opens upward, and includes a pair of output electrodes of the power supply unit. An ion generator that generates ions by connecting one to a needle electrode, connecting the other to an annular electrode that protrudes upward and surrounding the needle electrode, and discharging between the needle electrode and the annular electrode A cylindrical body which is located inside the annular electrode and surrounds the needle electrode, in which the casing is filled with resin to a position where both the needle electrode and the other electrode are exposed. The entire circumference of the lower end of the cylindrical body is buried in the molded resin so that the cylindrical body is fixed by the resin.

  In the state of being molded with the resin, the creepage distance between the needle electrode and the other electrode is a linear distance on the resin surface, which is the shortest distance. Therefore, a short circuit is likely to occur. However, when the acicular electrode is surrounded by the cylindrical body, the creepage distance between the acicular electrode and the other electrode is the distance from the surface of the resin to the upper end along the inner surface of the cylindrical body. A distance from the upper end to the surface of the resin is added along the outer surface, and the creepage distance is extended.

  A plate-like lid attached to the opening of the casing is provided, and the cylindrical body is formed integrally with the lid on the periphery of the through hole formed in the lid, and the lid is fixed via the cylindrical body. For example, the creepage distance from the needle electrode side is increased along the inner surface of the cylindrical body, in addition to the distance from the resin surface to the upper end, along the surface of the lid body. Can do.

  In order to further extend the creepage distance, for example, it is conceivable that an annular wall surrounding the cylindrical body is formed on the back side of the lid so as not to contact the surface of the molded resin. Thereby, the discharge path along the back side of the lid cannot reach the surface of the resin along the outer surface of the cylindrical body unless it once exceeds the annular wall.

  Further, if an annular groove reaching the inside wall thickness from the surface side of the lid is formed so as to surround the through hole at the position where the annular wall is formed, the discharge path is temporarily formed in the groove. The creepage distance is further extended because it is necessary to go up and go up the inner wall of the groove.

  Note that if the lid is fixed only through the cylindrical body, the holding strength against the casing may be low, but the lid is attached to the opening of the casing with the resin injected into the casing, and the resin is cured. The casing is tilted at a predetermined angle before the resin is brought into contact with the boundary between the lid and the casing, and then the casing is returned to its original posture, and the resin is cured in this state. Can be fixed directly.

  As is apparent from the above description, the present invention can extend the creeping distance between the needle electrode and the other electrode, thereby preventing a short circuit between them.

The figure which shows the structure of one embodiment of this invention Exploded perspective view showing internal structure The figure which shows the shape of the back of a lid Diagram showing resin filling state The figure which shows the swinging state of the casing after resin filling Figure showing creepage distance

  Referring to FIG. 1, reference numeral 1 denotes a casing that opens upward in the figure, and a plate-like lid 2 is attached to the opening. A power source 5 is housed inside the casing 1. A step-up transformer 51, which is one of the components constituting the power supply unit 5, converts low-voltage DC power supplied from the outside into AC power having a predetermined frequency. Boosts to generate AC power. The high-voltage AC power is applied to the needle electrode 3 and the annular electrode 4 disposed so as to surround the needle electrode 3 so that ions are generated by corona discharge generated between the two discharge electrodes. It is configured. The present invention is characterized in that a cylindrical body 6 surrounding the needle-like electrode 3 is provided on the back surface of the lid body 2.

  The above configuration will be described in more detail. Referring to FIG. 2, the step-up transformer 51 is provided with a pair of input terminals 50 and a pair of output terminals 51a and 51b. The low-voltage DC power supplied from the outside is input to the power supply board 52 and converted into low-voltage AC power by the power supply board 52. The converted AC power is input to the input terminal 50 of the step-up transformer 51. The voltage is boosted to high voltage AC power by the step-up transformer 51 and output from the output terminals 51a and 51b. One output terminal 51a is connected to an electrode substrate 41 on which the annular electrode 4 is provided, and the output terminal 51a and the annular electrode 4 are electrically connected.

  The other output terminal 51b is connected to the electrode substrate 31 on which the needle electrode 3 is held, and the output terminal 51b and the needle electrode 3 are connected via a diode (not shown) mounted on the electrode substrate 31. The inspection terminal 32 is connected so as to have the same potential as the needle electrode 3, and an inspection probe is connected through the inspection hole 22 of the lid 2. 21 of the lid 2 is a guard for preventing the tip of the needle electrode 3 from touching the outside.

  Referring to FIG. 3, a cylindrical body 6 that covers the two needle-like electrodes 3 and the inspection terminal 32 is provided integrally with the lid body 2 on the back surface of the lid body 2. As shown in FIG. 4, the lower end of the cylindrical body 6 is set to a length that is buried in the resin surface RS when the casing 1 is filled with resin (for example, urethane resin). Therefore, when the resin is cured, the lid body 2 is fixed to the resin via the three cylindrical bodies 6.

  However, if the lid body 2 is fixed only at these three points, a sufficient gap between the lid body 2 and the casing 1 is formed, and the holding strength of the lid body 2 cannot be sufficiently secured. Therefore, after filling the casing 1 with the resin, the casing 1 is swung as shown in FIG. 5 before the resin is cured. The casing 1 is swung to the left and right until the angle at which the resin surface RS contacts the mating portion A of the lid 2 and the casing 1. Then, the resin adheres to the mating part A. Thereafter, when the casing 1 is returned to its original state, the resin flows downward in the casing 1 due to gravity, but a small amount of the resin that remains on the mating portion A remains in the mating portion A. If the resin is cured in this state, the resin functions as an adhesive, and the lid 2 is bonded to the casing 1 at the mating portion A. Thereby, the holding strength of the lid 2 can be sufficiently ensured.

  When the structure described above is schematically shown in FIG. 6A, the creeping distance between the needle-like electrode 3 and the output terminal 51a is short unless the cylindrical body 6 exists, and therefore, due to creeping discharge along the surface RS of the resin. Although a short circuit may occur, the creeping distance between the two is greatly extended by the tubular body 6. That is, in order to cause a creeping discharge between the two, the cylindrical body 3 comes out from the needle-like electrode 3 along the inner surface of the cylindrical body 6, and then turns to the back side of the lid 2, and then the cylindrical body. The creeping discharge does not occur unless the resin surface RS falls along the outer surface 6 and reaches the resin surface RS. In this way, the creepage distance is greatly extended only by adding the cylindrical body 6, so that a short circuit is prevented from occurring between the needle electrode 3 and the output terminal 51a.

  In order to further extend the creeping distance, an annular wall 61 surrounding the cylindrical body 6 may be provided as shown in FIG. However, the lower end of the annular wall 61 needs to be set to a height that does not contact the surface RS of the resin. If this annular wall 61 is provided, even if a creeping discharge is generated from the back surface of the lid body 2 toward the outer surface of the cylindrical body 6, the creeping distance must be further extended because the creeping discharge must occur once. become.

  In order to further increase the creepage distance, an annular groove 62 reaching the thickness of the annular wall 61 from the surface side of the lid 2 is formed at the position where the annular wall 61 is formed, as shown in FIG. May be. As a result, the creepage distance is extended by a distance twice the depth of the annular groove 62.

  In addition, this invention is not limited to an above-described form, You may add a various change in the range which does not deviate from the summary of this invention. For example, it is also conceivable that the cylindrical body is not provided integrally with the lid but is provided alone and the lid is omitted. Even when the cylindrical body is provided alone, the creeping distance can be extended by a distance twice as high as the height of the cylindrical body, so that the possibility of occurrence of creeping discharge can be reduced.

DESCRIPTION OF SYMBOLS 1 Casing 2 Cover body 3 Needle-shaped electrode 4 Annular electrode 5 Power supply part 6 Tubular body 61 Annular wall 62 Annular groove RS The surface of resin

Claims (5)

  A power supply unit that generates a high voltage is housed in a bottomed casing that opens upward, and one of the pair of output electrodes of the power supply unit is connected to a needle electrode, and the other is directed upward. An ion generator for projecting and connecting to an annular electrode surrounding the needle-like electrode and generating an ion by discharging between the needle-like electrode and the annular electrode, wherein the needle-like electrode and the other electrode are both In the case where the casing is filled with resin up to the exposed position and molded, the cylindrical body that is located inside the annular electrode and surrounds the needle-like electrode is molded over the entire circumference of the lower end of the cylindrical body. An ion generator characterized in that it is buried in a resin and the cylindrical body is fixed by the resin.   A plate-like lid attached to the opening of the casing is provided, the cylindrical body is formed integrally with the lid on the periphery of the through-hole formed in the lid, and the lid is fixed via the cylindrical body. The ion generator of Claim 1 characterized by the above-mentioned.   The ion generator according to claim 2, wherein an annular wall surrounding the cylindrical body is formed on a back side of the lid body at a height that does not contact the surface of the molded resin.   The annular groove reaching the inside of the wall thickness of the annular wall from the surface side of the lid body is formed at a position where the annular wall is formed so as to surround the through hole. Ion generator.   A method of manufacturing an ion generator according to any one of claims 2 to 4, wherein the lid is attached to the opening of the casing in a state where the resin is injected into the casing, and before the resin is cured. A method of manufacturing an ion generator, comprising: tilting the casing at a predetermined angle, bringing the resin into contact with a boundary portion between the lid and the casing, then returning the casing to an original posture and curing the resin in that state.

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