JP2000040629A - High voltage generating coil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high voltage generation coil whose secondary voltage cannot be decreased, whose cost-up can be reduced to the minimum, and whose miniaturization can be attained. SOLUTION: A secondary coil 3e is wound around the outer periphery of a bobbin 3d for a secondary coil into which an iron core 3a is inserted, and a secondary coil 3c is wound around a bobbin 3b for a primary coil into which the bobbin 3d for a secondary coil is inserted, and they are housed in an insulating case 3f, and thermosetting resin 3g is packed in the insulating case 3f, and insulation is attained so that a high voltage generating coil 3 can be formed. In this case, the iron core 3a is divided into an internal iron core 3a1 formed by laminating or winding amorphous or permalloy thin plates in a bar-shape in the insulating case 3f, and an external iron core 3a2 formed by laminating or winding the amorphous or permalloy thin plates on the outer periphery of the insulating case 3f, and a closed magnetic path type magnetic circuit is constituted of the internal iron core 3a1 and the external iron core 3a2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high voltage generating coil such as a capacitor discharge type high voltage generating coil used for starting an HID lamp (high intensity discharge lamp) or igniting a gas combustor.

[0002]

2. Description of the Related Art FIG. 5 is a circuit diagram of a typical capacitor discharge type high voltage generator for starting a HID lamp. In FIG. 5, 1 is a battery, 2 is a DC-DC converter (DC-DC converter), 3 is a high voltage generating coil, 4 is a capacitor, and 5 is a thyristor. The high-voltage generating coil 3 includes an iron core 3a made of ferrite, a primary coil 3c wound around the outer periphery of the iron core 3a, and a secondary coil 3e wound around the outer periphery of the iron core 3a. The reason why the iron core 3a is made of ferrite in this way is that the oscillation frequency of the primary current of the high-voltage generating coil 3 is a high frequency of about 500 kHz, and that the iron loss at the high frequency is small.

[0003] The capacitor discharge high voltage generator shown in Figure 5, and charged to the charging voltage V _C of about 300 V (volts) capacitor 4 with a DC-DC converter 2, to turn on the thyristor 5 at an appropriate time by rapidly applying a charging voltage V _C to the primary coil 3c Te, the secondary coil 3
It is intended to generate a secondary voltage V ₂ of about 20kV to e.

FIG. 6 is an explanatory diagram showing a configuration of an example of a conventional high voltage generating coil. In FIG. 6, reference numeral 3 denotes a high voltage generating coil, a ferrite core 3a, a primary coil bobbin 3b formed of a synthetic resin and having a primary coil 3c wound around the outer periphery, and a synthetic resin molded outer periphery 3b. The primary coil bobbin 3d in which the secondary coil 3e is wound, and is inserted through the primary coil bobbin 3b, and the secondary coil bobbin 3d into which the iron core 3a is inserted, and the core 3a and the primary coil 3c are wound. 3b and an insulating case 3f accommodating a secondary coil bobbin 3d around which a secondary coil 3e is wound.
And a thermosetting resin 3g as an insulating material for fixing the iron core 3a, the bobbins 3b and 3d, and the coils 3c and 3e housed in the insulating case 3f and performing high voltage insulation between them. I have.

The primary coil bobbin 3b and the secondary coil bobbin 3d are formed in concentric cylindrical shapes. The primary coil 3c has an outer diameter of a 0.5mm approximately enameled wire, are wound around the winding number N ₁ as 3. The secondary coil 3e are the enameled wire of about the outer diameter of 0.3 mm, are wound a number of turns N ₂ as 200.

[0006]

As described above, when the iron core 3 is made of ferrite, the high-frequency characteristics are excellent, but the saturation magnetic flux density becomes about 0.3 T at high temperatures.
(Tesla), the vertical cross-sectional area (cross-sectional area perpendicular to the magnetic flux) of the iron core 3 needs to be about 10 mm square in order to compensate for this decrease in the saturation magnetic flux density. Become large. Therefore, it is conceivable to manufacture the iron core 3 using an amorphous alloy or permalloy, which is a magnetic metal having excellent high-frequency characteristics and a high saturation magnetic flux density. However, when manufacturing the iron core 3 using an amorphous alloy or permalloy, a ring-shaped or cut core may be used. It has not been put to practical use because it is U-shaped and expensive.

When a cut core made of ferrite, amorphous alloy, or permalloy is used, as shown in FIG. 6, the magnetic gap G is located near the center of both coils 3c and 3e. When the coupling coefficient of the secondary coil 3e is deteriorated, the secondary voltage V ₂ is about 10% lower than the ideal value.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned disadvantages, and has a high voltage generating coil capable of miniaturizing while minimizing cost increase without lowering secondary voltage. Is provided.

[0009]

According to the present invention, a primary coil and a secondary coil are wound around an outer periphery of a bobbin in which an iron core is inserted, housed in an insulating case, and the insulating case is filled with a resin to perform insulation. In a high-voltage generating coil, an iron core is formed by laminating or winding an amorphous or permalloy thin plate into a rod shape and stored in an insulating case, and an amorphous or permalloy thin plate is stacked or wound around the outer periphery of the insulating case. And a closed magnetic circuit is constituted by the inner core and the outer core.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view showing a high voltage generating coil according to an embodiment of the present invention, and FIG. 2 is a plan sectional view of the high voltage generating coil shown in FIG. 1, which is the same as or equivalent to FIGS. Are given the same reference numerals and description thereof is omitted. In FIG. 1, reference numeral 3a ₁ denotes an inner core constituting the iron core 3a, which is formed by laminating or winding an amorphous or permalloy thin plate (laminate tape) into a rod shape, and is inserted into a secondary coil bobbin 3d. Insulation case 3
f.

Reference numeral 3a ₂ denotes an armor core constituting the iron core 3a, which is formed by laminating or winding an amorphous or permalloy thin plate (laminate tape) on the outer periphery of the insulating case 3f. The amorphous or permalloy thin plate used had a thickness of 18 μm to 30 μm. The outer core 3a ₂ of the width (height) W ₂ is decorated core 3a
₁ of maximum width are to 3 to 5 times the (maximum height) W _1.

[0012] Here, to describe the vertical area of the interior core 3a _1, amorphous alloy or Permalloy,
Since the saturation magnetic flux density is about 1.4T (tesla) and the saturation magnetic flux density hardly changes even when the temperature becomes high, the number of turns of the primary coil and the secondary coil is the same as that of ferrite, but the vertical cross-sectional area is Can be reduced to about 1/5. However, since an amorphous alloy or permalloy has a larger iron loss than ferrite, it is necessary to use it with a reduced magnetic flux density. Therefore, it is appropriate to set the vertical cross-sectional area to about one third of that of ferrite. Thus, the longitudinal area of the interior core 3a _1, about 6mm angle ^{[10 2 (mm 2) ÷ 3} ≒ 34 (mm
² ) ≒ 6 ² (mm ² )].

Next, the interior iron core 3a₁And armor core 3a_TwoWhen
, Ie the armor core 3a _TwoAmol that constitutes
Fasu alloy or permalloy sheet
Described as a board. ) The number of windings
Heart 3a₁36mm vertical cross-sectional area^TwoIf the
3a_TwoIdeally, the vertical sectional area of the interior iron core 3a₁Profile
Half of the area (18mm^Two), But practical
The interior iron core 3a₁About 35% (70% ÷)
2) 12.6 mm^Two[36 (mm
^Two) × 0.7 ÷ 2 = 12.6 (mm^Two)]
It will be good.

[0014] Incidentally, the ideal of a longitudinal area of the outer core 3a ₂ is half of a longitudinal area of the interior core 3a _1, the practical whether more than about 35%, to half the magnetic flux from the interior core 3a ₁ This is because they are divided into right and left. The exterior sheet constituting the outer core 3a _2, for convenience, the thickness of 20 [mu] m.

[0015] 12.6m sectional area of the outer iron core 3a ₂
In order to secure m ² , the width W _{2 of the} outer thin plate must be
If you 3 times the maximum width W ₁ of a _1, the number of turns of the exterior sheet is 35 times [12.6 (mm ²⁾ ÷ [0.02 (mm)
× 6 (mm) × 3] = 35], and also, when the width W ₂ of the outer thin plate 4 times the maximum width W ₁ of the interior core 3a _1, the number of turns of the exterior sheet is 27 times [12. 6 (mm ² )
÷ [0.02 (mm) × 6 (mm) × 4] = 26.2
5], and further, interior core 3a width W ₂ of the outer sheet
_When the maximum width W ₁ is five times the maximum width W _1, the number of turns of the exterior thin plate is 21 [12.6 (mm ² ) ÷ [0.02 (mm)
.Times.6 (mm) .times.5] = 21].

[0016] Thus, when more than three times the maximum width W ₁ of the interior core 3a ₁ width W ₂ of the exterior sheet, it is possible to reduce the number of turns of the outer sheet, the better the productivity. Also, when the 4 times the maximum width W ₁ of the interior core 3a ₁ width W ₂ of the outer sheet, in addition to the productivity is improved, it can be made compact (thinned). Also, the width W _{2 of the} outer thin plate is changed to the inner core 3a.
_When the maximum width W ₁ is three times as large as _1, the size can be further reduced (thinned). Therefore, miniaturization can be achieved while minimizing cost increase.

[0017] Subsequently explained magnetic gap length G between the interior core 3a ₁ and the outer core 3a _2, 1mm~3
By setting the thickness in mm, it is possible to prevent magnetic saturation of the two cores 3a ₁ and the armature core 3a ₂ during energization, and to reduce leakage magnetic flux. And since the magnetic air gap length G is located in a portion deviating from both coils 3c and 3d,
The coupling coefficient between the primary coil 3c and the secondary coil 3e is good,
A secondary voltage characteristic close to an ideal value is obtained.

FIGS. 3 (a) and 3 (b) are explanatory views showing examples of shaping the interior iron core shown in FIGS. 1 and 2. FIG. This figure 3
Referring to shaping of the interior core 3a ₁ on the basis of,
As shown in FIG. 3 (a), an amorphous or permalloy thin plate having a width of 6 mm is laminated with a predetermined length so as to finally have a height (maximum width) of 6 mm, and then shown in FIG. 3 (b). as described above, by shaping, it can be decorated core 3a _1.

FIGS. 4A and 4B are explanatory views showing another example of shaping the interior iron core shown in FIGS. 1 and 2. FIG. Referring to shaping of the interior core 3a ₁ on the basis of FIG. 4, as shown in FIG. 4 (a), eventually 6mm thin plates amorphous or permalloy width 6mm a predetermined length
After winding to a height (maximum width) of FIG.
As shown in ( ₁₎ , the interior iron core 3a1 can be formed by shaping.

In the above-described embodiment, the bobbin is composed of the primary coil bobbin 3b and the secondary coil bobbin 3d. However, the primary coil and the secondary coil may be wound around the outer periphery of one bobbin. It goes without saying that it is good. Also, HI
The capacitor discharge type high voltage generating coil for firing the D lamp has been described as an example, but it is needless to say that the present invention can be applied to a capacitor discharge type high voltage generating coil for gas combustor ignition or gasoline engine ignition.

[0021]

As described above, according to the present invention, it is possible to reduce the size while minimizing the cost increase without lowering the secondary voltage.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a high voltage generating coil according to an embodiment of the present invention.

FIG. 2 is a plan sectional view of the high-voltage generating coil shown in FIG.

FIGS. 3A and 3B are explanatory views showing one example of shaping the interior iron core shown in FIGS. 1 and 2. FIG.

FIGS. 4A and 4B are explanatory views showing another example of shaping the interior iron core shown in FIGS. 1 and 2. FIG.

FIG. 5 is a circuit diagram of a typical HID lamp firing capacitor discharge high voltage generator.

FIG. 6 is an explanatory diagram showing a configuration of an example of a conventional high-voltage generating coil.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Battery 2 DC-DC converter 3 High voltage generating coil 3a Iron core 3a ₁ Interior iron core 3a ₂ Exterior iron core 3b Primary coil bobbin 3c Primary coil 3d Primary coil bobbin 3e Secondary coil 3f Insulation case 3g Thermosetting resin 4 Capacitor 5 thyristor W ₁ maximum width W ₂ width V _C the charging voltage V ₂ secondary voltage

Claims (3)

[Claims] 1. A high voltage generating coil in which a primary coil and a secondary coil are wound around an outer periphery of a bobbin through which an iron core is inserted, housed in an insulating case, and the insulating case is filled with resin to be insulated. An iron core is formed by laminating or winding an amorphous or permalloy thin plate into a rod shape and housed in the insulating case, and an outer core is formed by laminating or winding an amorphous or permalloy thin plate around the outer periphery of the insulating case. Wherein the interior core and the exterior core constitute a closed magnetic circuit type magnetic circuit. 2. The high voltage generating coil according to claim 1, wherein a width of the armor core is at least three times a maximum width of the inner core, and a vertical cross-sectional area of the armor core is about a vertical cross-sectional area of the inner core. A high voltage generating coil, which is 35% or more. 3. The high-voltage generating coil according to claim 1, wherein a magnetic gap length between the inner core and the outer core is one.
A high-voltage generating coil having a diameter of 3 mm to 3 mm.