JP4453289B2 - High voltage transformer - Google Patents

Description

  The present invention relates to a high-voltage transformer that is configured by winding a high-voltage winding composed of a plurality of winding portions divided and connected in series around an outer peripheral surface of a cylindrical bobbin and used in a high-voltage generating circuit.

  FIG. 5 is a configuration diagram of a bobbin used in a conventional high-voltage transformer, FIG. 6 is a schematic cross-sectional view of the high-voltage transformer using the bobbin, and FIG. 7 is a diagram showing a part of a high-voltage unit with electrodes including the high-voltage transformer. is there. However, in FIG. 7, when (a) is a front view, (b) is a left side view and (c) is a right side view.

  5 and 6, the conventional high-voltage transformer is for magnetic coupling between a bobbin 4 made of insulating resin and a low-voltage winding 6 and a high-voltage winding 7 which will be described later, and a shaft hole 4a of the bobbin 4. The core 5 housed inside, the low-voltage winding 6 as the primary winding, the high-voltage winding 7 as the secondary winding, both ends of the low-voltage winding 6 and both ends of the high-voltage winding 7 are connected. As shown in FIG. 7, a high voltage unit U with electrodes is formed by molding with a resin R.

  In the above high-voltage transformer, a high-voltage winding 7 composed of a plurality of (three in the examples of FIGS. 5 and 6) winding parts connected in series is used in order to reduce the distributed capacitance and prevent the inductance from decreasing. ing. That is, the high-voltage winding 7 is wound in a plurality of layers on the outer peripheral surface of the bobbin 4 between the flanges F2 and F3 of the bobbin 4 as a first winding portion, and is passed through the notch groove F30 of the flange F3 to be the second winding. A plurality of layers are wound around the outer peripheral surface of the bobbin 4 between the flanges F3 and F4 of the bobbin 4 as a line part, passed through the notch groove F40 of the flange F4, and between the flanges F4 and F5 of the bobbin 4 as a third winding part. A plurality of layers are wound around the outer peripheral surface of the bobbin 4.

In Patent Document 1, in order to increase the number of turns and increase the step-up rate without increasing the size in the radial direction around the core leg, insulation of the bobbin is performed according to the voltage value of each winding part. A high-voltage transformer in which the cylinder thickness is set in stages is disclosed.
JP-A-5-315159

  However, in the conventional high-voltage transformer shown in FIG. 5 and FIG. 6, the surface layer portion of one winding portion adjacent to each other moves to the inner layer portion of the other winding portion, and a high potential difference is generated between both surface layer portions. Therefore, a necessary and sufficient insulation distance must be ensured between the surface layer portions adjacent to each other.

  In addition, in order to increase the voltage generated between the high-voltage windings, the number of turns of each winding portion must be increased, so the insulation distance to be secured becomes longer, the high-voltage transformer becomes larger, and it is used. Devices such as high voltage units with electrodes will also become larger.

  In addition, in the high voltage unit with electrodes, it is molded with resin or the like in order to insulate the high voltage generating part. However, since such resin has a minute impedance, a leakage current is caused by a high potential difference between adjacent surface layer parts. Can occur.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a high-voltage transformer that can shorten the insulation distance required between both surface layer portions adjacent to each other in a high-voltage winding. To do.

According to the first aspect of the present invention, the high voltage winding composed of the first winding portion and the second winding portion divided and connected in series is connected to the outer peripheral surface of the cylindrical bobbin in the winding direction of the high voltage winding. one to a high-voltage transformer which are wound respectively around the region formed by equally dividing, the first winding portion, a plurality of layers at a predetermined pitch in Ri same times from one end of the bobbin in the winding axis direction Is provided in a region on one end side of the outer peripheral surface in the winding axis direction , and the second winding portion is different from the first winding portion from the other end side of the bobbin in the winding axis direction. In the reverse direction, the first winding portion is wound in a plurality of layers at the same pitch and the same number of turns, and is provided in a region on the other end side of the outer peripheral surface in the winding axis direction. The second winding portion is electrically connected to each other at both surface layer portions. To.

  In this configuration, both inner layers of the first winding portion and the second winding portion are placed in a state where the potential difference is the largest, and both surface layers of the first winding portion and the second winding portion are electrically connected to each other. Since the potential difference between the parts can be made the smallest (no potential difference or considerably reduced), the insulation distance required between the adjacent surface layer parts in the high-voltage winding can be shortened compared to the prior art. Can do.

  According to a second aspect of the present invention, in the high-voltage transformer according to the first aspect, the bobbin holds a plurality of terminals on an end surface of a flange formed at one end of the bobbin, and the second winding portion includes the second winding portion. One end side of the winding portion is inserted into the bobbin from the other end side of the bobbin, and one end of the second winding portion is connected to one terminal of the plurality of terminals, while the second winding portion The side opposite to one end of the part is wound around the other end of the bobbin. In this configuration, since one end side connected to the inner layer portion of the second winding portion passes through the inside of the first winding portion with the bobbin interposed therebetween, it is suitably insulated from the first winding portion. It will be.

  According to a third aspect of the present invention, in the high-voltage transformer according to the second aspect, a core is inserted into the bobbin. In this configuration, for example, by winding the low-voltage winding around the core, the magnetic coupling between the low-voltage winding and the high-voltage winding can be performed in a suitably miniaturized state.

  According to a fourth aspect of the present invention, in the high-voltage transformer according to the third aspect, a slit that penetrates between both ends of the bobbin is formed in the bobbin, and one end side of the second winding portion is in addition to the bobbin. It is wired from the end side to the end face side of the flange along the inside of the slit inside the bobbin. In this configuration, the one end side of the second winding portion inserted into the bobbin and the coil can be arranged separately.

  According to the present invention, the insulation distance required between both surface layer portions adjacent to each other in the high-voltage winding can be shortened as compared with the prior art.

  FIG. 1 is a diagram showing an example of a manufacturing procedure of a high-voltage transformer according to an embodiment of the present invention, FIG. 2 is a sectional view of the high-voltage transformer, FIG. 3 is a diagram showing a primary winding and a core of the high-voltage transformer, and FIG. It is a block diagram of the high voltage unit with an electrode including the high voltage transformer.

  However, in FIG. 1, (a), (b), and (c) respectively show a side view, a bottom view, and a top view of the bobbin. (D), (e) shows the side view and bottom view of the bobbin in the middle of which the secondary winding is wound around one of the two outer sides. (F), (g) shows a side view and a bottom view of the bobbin in a state where the secondary winding has been wound on one of them. (H), (i), and (j) respectively show a side view, a bottom view, and an upper side view of the bobbin in the middle of which the secondary winding is wound around the other outer surface. (K), (l), (m) are side and bottom views of the bobbin in a state where the core wound with the primary winding is housed inside after the secondary winding has been wound on the other side. The upper side view is shown respectively. FIG. 2 is a cross-sectional view taken along the line AA in FIG.

  The high-voltage transformer of this embodiment shown in FIGS. 1 to 3 includes a pair of terminals 1 and 1 on the primary side, a pair of terminals 2 and 2 on the secondary side, an intermediate tap 3, and a bobbin 4 made of insulating resin. 4 includes a core 5, a low-voltage winding 6 as a primary winding, and a high-voltage winding 7 as a secondary winding, and is molded with resin R to form a high-voltage unit with electrodes as shown in FIG. is doing. This high voltage unit with electrodes generates negative ions with an output of −3.0 kV or less, for example.

  In the high-voltage unit with electrodes, the pair of lead wires L1 and L1 connected to the connector C1 are connected to the pair of terminals 1 and 1 of the high-voltage transformer, respectively. On the other hand, the pair of lead wires L2 and L2 connected to the discharge needle H1 and the counter electrode plate H2 provided in the discharge electrode housing H are connected to the pair of terminals 2 and 2 side of the high-voltage transformer, respectively. For example, the high-voltage transformer is mounted on a printed circuit board (not shown) for generating high voltage, and the pair of lead wires L1 and L1 are connected to the printed circuit board, and the pair of terminals 1 and 1 of the high-voltage transformer are connected via the printed circuit board line. 1 side is connected. The pair of lead wires L2 and L2 are also connected to the same printed circuit board, and are respectively connected to the pair of terminals 2 and 2 side of the high-voltage transformer via the printed circuit board line.

  Returning to FIGS. 1 to 3, the bobbin 4 includes a cylindrical portion 40 formed in a cylindrical shape, flanges 41 and 42 extending at both ends (lower and upper ends), and an outer periphery of the cylindrical portion 40. An end surface of the flange 41 that is formed in a shape integrally having a flange 43 that is provided around the surface 400 and equally divides the outer peripheral surface 400 into two upper and lower regions, and is thicker than the flanges 42 and 43 having substantially the same thickness. A part of each of the terminals 1, 1, 2, 2 and the intermediate tap 3 is embedded and held in the (lower surface) 410.

  On the end face 410 of the flange 41, the primary side terminals 1, 1 and the secondary side intermediate tap 3 and the terminals 2, 2 on both sides thereof are arranged to face each other, and a V-shape is provided between the primary side and the secondary side. On the other hand, a V-shaped slit 412 is formed between the intermediate tap 3 and each terminal 2, while a rib 411 is extended across the shaft hole 4 a of the bobbin 4. In addition, a pair of columnar protrusions 413 and 413 project in the middle of both ends of the rib 411 and both ends of the slit 412 on the end face 410 of the flange 41. Further, the flange 41 is formed with a notch groove 414 whose deepest portion is continuous with the lower region of the outer peripheral surface 400 between one end of the ribs 411 adjacent to each other and one protrusion 413, near the intermediate tap 3. A groove 415 extending vertically is formed on the outer peripheral surface.

  A linear slit (groove) 402 that penetrates between both ends of the bobbin 4 along the axis of the cylindrical portion 40 is formed on the inner peripheral surface 401 of the cylindrical portion 40, and a rib 411 and a slit 412 on the other projection 413 side. Is formed between. On the end surface (upper surface) 420 of the flange 42, a notch groove 421 whose deepest portion is continuous with the region on the upper side of the outer peripheral surface 400 is formed at an opposing position near the slit 402.

  The core 5 is formed of, for example, a cylindrical and high-resistivity ferrite core (Ni—Zn ferrite core), and is housed and disposed in the bobbin 4 with the low-voltage winding 6 wound around the outer peripheral surface. The low-voltage winding 6 wound around the core 5 is made of, for example, a conductor wire with an insulating film, and both ends are wrapped around the terminals 1 and 1 and fixed by soldering.

  The high-voltage windings 7 are the same, and are composed of, for example, a first winding portion and a second winding portion of a conductor wire with an insulating coating. The first winding portion is wound in a plurality of layers at a predetermined pitch around the same end from the one end (lower end) side of the outer peripheral surface 400 of the bobbin 4 and is provided in a lower region of the outer peripheral surface 400. On the other hand, the second winding portion is wound from the other end (upper end) side of the outer peripheral surface 400 of the bobbin 4 to the same plurality of layers at the same pitch as that of the first winding portion in the reverse direction. Is provided in the area. The first winding portion and the second winding portion are electrically connected to each other by being connected to the intermediate tap 3 at both surface layer portions to form one coil. Then, both ends of the high-voltage winding 7 formed as one coil are wrapped around the terminals 2 and 2 and fixed by soldering.

  Next, an example of a procedure for manufacturing the high-voltage transformer of this embodiment will be described with reference to FIG. First, as shown in FIGS. 1A to 1C, a bobbin 4 that holds the terminals 1, 2, 2, and the intermediate tap 3 is prepared.

  Thereafter, as shown in FIGS. 1D and 1E, one end (start of winding) of the first winding portion of the high-voltage winding 7 is connected to one terminal 2 having the notch groove 414, and in the vicinity thereof. After one turn from one protrusion 413, it is drawn from the notch groove 414 into the lower region of the outer peripheral surface 400, and reciprocated from the lower end side of the outer peripheral surface 400 counterclockwise at a predetermined pitch when viewed from the lower surface of the bobbin 4. While winding in multiple layers. Subsequently, when the winding is completed, as shown in FIGS. 1 (f) and (g), the other end (winding end) side of the first winding portion is placed in the groove 415 of the flange 41 and toward the end face 410 side. Pull back, and connect the other end of the first winding portion to the intermediate tap 3.

  Thereafter, as shown in FIGS. 1 (h), (i), and (j), one end side of the second winding portion of the high-voltage winding 7 is placed along the slit 402 from the flange 42 side to After one turn from the other protrusion 413 near the slit 402 on the end face 410, one end of the second winding portion is connected to the other terminal 2. Subsequently, the side opposite to one end of the second winding part is drawn into the region above the outer peripheral surface 400 from the notch groove 421, and clockwise from the upper end side of the outer peripheral surface 400 as viewed from the lower surface of the bobbin 4 (bobbin 4 It is wound around a plurality of layers while reciprocating at a predetermined pitch counterclockwise when viewed from the top. Then, when the winding is completed, as shown in FIGS. 1 (k), (l), and (m), the other end side of the second winding portion is notched in the flange 43 in the same direction as the groove 415. (Not shown), and pulled back toward the end face 410 along the groove 415 of the flange 41, and the other end of the second winding portion is connected to the intermediate tap 3.

  Also, a core 5 having a low-voltage winding 6 wound around the outer peripheral surface is prepared, and both ends of the low-voltage winding 6 are inserted into the shaft hole 41a of the bobbin 4 from the rib 42 side, and from the narrow angle side of the rib 411. The two ends of the low-voltage winding 6 are connected to the terminals 1 and 1, respectively. Note that the low voltage winding 6 wound around the outer peripheral surface of the core 5 is impregnated with at least an insulating varnish, and the insulating tape IT is further wound in the example of FIG. Further, the same impregnation is applied to the high-voltage winding 7.

  As described above, according to the present embodiment, the first winding portion and the second winding portion of the high-voltage winding 7 include the one terminal 2 having the notch groove 414, one end of the first winding portion, the first Since the other end of the winding part, the intermediate tap 3, the other end of the second winding part, one end of the second winding part, and the other terminal 2 path are formed, as viewed from the end face 410 of the flange 41, It turns out that it becomes one coil wound counterclockwise. As a result, the first winding portion and the second winding portion that are electrically connected to each other by the intermediate tap 3 with the largest potential difference between the inner layer portions of the first winding portion and the second winding portion. Between the two surface layer portions can be in a state where the potential difference is the smallest (the state where there is no potential difference or is considerably reduced). For example, if the number of turns of the first winding portion and the second winding portion is the same, the voltage between the terminals 2 and 2 is 2 of the potential difference generated in each of the first winding portion and the second winding portion. The voltage is doubled and becomes the same potential at the intermediate tap 3, and the potential difference between the first winding portion and the second winding portion is smaller on the surface layer side and larger on the inner layer side.

  According to this embodiment, the first winding portion and the second winding portion that are electrically connected to each other with the largest potential difference between the inner layer portions of the first winding portion and the second winding portion. Therefore, the insulation distance required between the surface layers adjacent to each other in the high-voltage winding can be shortened as compared with the prior art. As a result, the high-voltage transformer can be reduced in size, and the number of turns of the first winding portion and the second winding portion can be increased as compared with the prior art.

  Further, by using the high-voltage transformer of this embodiment for the high-voltage unit with electrodes, it is possible to reduce the size of the high-voltage unit with electrodes. Further, since the surface layer portions adjacent to each other can be in a state where there is no potential difference or is considerably reduced, it is possible to reduce or prevent leakage current, and the high voltage unit with electrodes in a high temperature and high humidity environment. Reliability can be improved.

It is a figure which shows the example of a preparation procedure of the high voltage transformer of one Embodiment by this invention. It is sectional drawing of the high voltage transformer. It is a figure which shows the primary winding and core of the high voltage transformer. It is a block diagram of the high voltage unit with an electrode including the high voltage transformer. It is a block diagram of the bobbin used for the conventional high voltage transformer. It is a schematic sectional drawing of the high voltage transformer which uses the bobbin. It is a figure which shows a part of high voltage | pressure unit with an electrode containing the same high voltage | pressure transformer.

Explanation of symbols

1 terminal 2 terminal 3 intermediate tap 4 bobbin 4a shaft hole 40 cylindrical portion 400 outer peripheral surface 401 inner peripheral surface 402 slit 41 flange 410 end surface 411 rib 412 slit 413 protrusion 414 notch groove 415 groove 42 flange 420 end surface 421 flange 5 notch 43 flange Core 6 Low voltage winding 7 High voltage winding

Claims (4)

A region formed by equally dividing the outer peripheral surface of a cylindrical bobbin into two in the winding axis direction of the high-voltage winding of the high- voltage winding composed of the first winding portion and the second winding portion divided and connected in series each a high-voltage transformer constructed by winding the said first winding portion, from said one end of the bobbin in the winding axis direction is wound in a plurality of layers at a predetermined pitch in Ri same times winding axis provided on one end side area of the outer peripheral surface in the direction, the second winding portion, said first winding from the other end of the bobbin in the winding axis direction opposite direction from said first winding portion Wound in a plurality of layers with the same pitch and the same number of turns as the part, provided in the region on the other end side of the outer peripheral surface in the winding axis direction , the first winding part and the second winding part, A high-voltage transformer characterized by being electrically connected to each other at both surface layer portions.   The bobbin holds a plurality of terminals on an end face of a flange formed at one end of the bobbin, and the second winding portion has an end side of the second winding portion from the other end side of the bobbin to the inside of the bobbin. One end of the second winding part is connected to one terminal of the plurality of terminals, while the side opposite to one end of the second winding part is wound around the other end side of the bobbin. The high-voltage transformer according to claim 1, wherein   The high voltage transformer according to claim 2, wherein a core is inserted into the bobbin.   A slit that penetrates between both ends of the bobbin is formed inside the bobbin, and one end side of the second winding portion extends from the other end side of the bobbin along the slit in the bobbin to the flange. 4. The high voltage transformer according to claim 3, wherein the high voltage transformer is wired on an end face side.

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