JP2001093478A - Electrodeless discharge lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrodeless discharge lamp which shows big radiation effect and uses an excitation coil that can suppress shielding of a bundle of output light as much as possible by simply winding the excitation coil. SOLUTION: In an electrodeless discharge lamp comprising a bulb 4 and an excitation coil 3 which is arranged close to an outer circumference of the bulb 4, a plasma discharge is generated inside of the bulb 4 by conducting high-frequency current 2 through the excitation coil 3, wherein the excitation coil 3 has a flat shaped cross section and is wound around the bulb 4 along a direction of one light radiated from the bulb 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrodeless discharge lamp.

[0002]

2. Description of the Related Art Conventional techniques (JP-A-5-89853,
Hereinafter, the prior art 1) will be described with reference to FIGS.
FIG. 10 shows the entire discharge lamp device. An excitation coil 20 is provided around the bulb 10 and both ends thereof are connected to a high-frequency power supply 30.
Connected to FIG. 11 shows a cross-sectional view of the discharge lamp device. The cross section of the excitation coil 20 has a flat shape and extends in a direction intersecting the coil axis OO. Excitation coil 2
The fact that the cross section of 0 is a flat shape means that the heat dissipation effect is increased by increasing the surface area as compared with the case where the cross section is circular, and a rise in the surface temperature of the excitation coil 20 can be suppressed. There is an advantage that the loss due to overcurrent is reduced by increasing the distance between the excitation coils 20.
In another conventional technique (Japanese Patent Laid-Open No. 5-325608, hereinafter referred to as Conventional Technique 2), as shown in FIG. 12, an excitation coil 20 having a flat cross section is wound along a plurality of light emission directions. .

In the prior arts 1 and 2, the excitation coil 20 is wound along a plurality of radiation directions of light, whereas in other prior arts (Japanese Patent Laid-Open No. 8-87988, hereinafter referred to as prior art 3). As shown in FIG. 13, the excitation coil 20 is wound along the direction in which one light is emitted, and there is an advantage that the shielding of the output light beam by the excitation coil 20 can be made relatively small.

[0004]

However, in the arrangements of the prior arts 1 and 2, since the excitation coil 20 is wound in a plurality of light emission directions, the number of turns of the excitation coil 20 increases as the number of turns of the excitation coil 20 increases. There is a disadvantage that the output light flux is significantly reduced. Specifically, in the prior art 1, the excitation coil 20
Has a disadvantage that the flattening direction of the cross section is perpendicular to the radiation direction of the light, so that the tendency of the output light beam to be blocked is increased, and the prior art 2 has a disadvantage that the winding method of the excitation coil 20 is difficult.

In the prior art 3, the prior arts 1 and 2 are used.
Although the output light beam is less light-shielded as compared with the above, there is a disadvantage that the cross section of the excitation coil 20 is not flat and the surface area of the excitation coil 20 is small, so that the heat radiation effect is low and the temperature is high.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electrodeless discharge lamp using an excitation coil which has a large heat radiation effect and can suppress the shielding of an output light beam as much as possible by a simple winding method. .

[0007]

In order to achieve the above object, the present invention comprises a valve and an excitation coil disposed close to the outer periphery of the valve, and a high frequency current is supplied to the excitation coil. In an electrodeless discharge lamp for generating a plasma discharge inside the bulb and lighting the bulb, the excitation coil has a flat cross section, and is wound around the bulb along the direction of emission of one light from the bulb. It is characterized by having been done.

[0008] According to the second aspect of the present invention, a first aspect is provided.
In the invention described above, the excitation coil is wound so that a long side of a cross section of the excitation coil is substantially perpendicular to a direction in which one light is emitted.

According to the third aspect of the present invention, there is provided the first aspect.
In the invention described above, the excitation coil is wound so that a short side of a cross section of the excitation coil is substantially perpendicular to a direction in which one light is emitted.

[0010] According to the fourth aspect of the present invention, a first aspect is provided.
In the described invention, at least in the closest part of the bulb, the excitation coil is arranged such that a long side of the cross section is substantially perpendicular to the direction of emission of one light, and a short side of the cross section is outside the bulb. The excitation coil is arranged so as to be substantially perpendicular to the direction of emission of one light.

According to the fifth aspect of the present invention, the first aspect is provided.
In the invention described above, a flat shape of a cross section of the excitation coil is a polygon or an ellipse.

According to the sixth aspect of the present invention, there is provided the fifth aspect.
In the described invention, in a cross section of the excitation coil,
An unevenness is provided on the outer periphery of the polygon or the ellipse.

According to the seventh aspect of the present invention, in the fifth aspect,
In the invention described above, the polygon is a quadrangle.

In the invention according to claim 8, claim 1 is
In the invention described in the above, the excitation coil is manufactured by molding.

According to the ninth aspect of the present invention, the first aspect is provided.
In the invention described above, a holding mechanism for accommodating the excitation coil is provided.

According to a tenth aspect of the present invention, in the ninth aspect of the present invention, the holding mechanism has a bobbin structure having a groove.

According to an eleventh aspect of the present invention, in the ninth aspect of the present invention, the holding mechanism is formed by integrally molding the excitation coil and a resin or the like. .

According to a twelfth aspect of the present invention, the apparatus comprises a valve and an excitation coil disposed close to the outer periphery of the valve, and a high-frequency current is applied to the excitation coil so that plasma is generated inside the valve. In an electrodeless discharge lamp that emits light by generating a discharge, the excitation coil has a flat cross section, and a long side of the cross section of the excitation coil is one along a radiation direction of one light from the bulb. It is characterized by having a holding mechanism that is wound around the bulb so as to be substantially perpendicular to the light emission direction and houses the excitation coil.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment of the present invention will be described with reference to FIGS. FIG.
1 shows an electrodeless discharge lamp 1 according to a first embodiment of the present invention, wherein (a) is a circuit diagram of the electrodeless discharge lamp 1,
(B) is an external view of the excitation coil 3. FIG. 2 shows an electrodeless discharge lamp 1 according to the embodiment, in which (a)
2 is a cross-sectional view of the excitation coil 3, and FIG. 2B is a cross-sectional view of the excitation coil 3 with the bobbin attached to FIG. Electrodeless discharge lamp 1
Is connected to the high frequency power supply 2 via the terminals A and B
, And a bulb 4 disposed close to the excitation coil 3. When a high-frequency current flows from the high-frequency power supply 2 to the excitation coil 3, a plasma discharge is generated inside the bulb 4. Generates and lights up. As shown in FIG. 1B and FIG. 2A, the excitation coil 3 has a flat cross-sectional shape, and a long side of the cross-section is substantially perpendicular to the direction of emission of one light from the bulb 4. Is wound twice around the bulb 4 as described above. FIG.
By using the bobbin 5 as shown in (b), the shape of the excitation coil 3 is maintained.

According to the present embodiment, the excitation coil 3 is wound twice around the bulb 4 so that the long side of the flat cross section is substantially perpendicular to the direction of emission of one light from the bulb 4. Therefore, the heat radiation effect is increased by increasing the surface area of the excitation coil 3, so that the temperature rise of the excitation coil 3 can be suppressed, and even if the number of windings increases, the light shielding of the output light beam by the excitation coil 3 can be suppressed. In addition, since the spread of the excitation coil 3 in the light emission direction is reduced as compared with the related art, the electrodeless discharge lamp 1 itself can be made compact, and the design of a lighting fixture that houses the electrodeless discharge lamp 1 can be designed. The degree of freedom can be increased. The excitation coil 3
Can be manufactured by molding, and the excitation coil 3 can be easily wound. Further, by using the bobbin 5 for holding the excitation coil 3 as shown in FIG. 2B, the excitation coil 3 can be easily fixed and the shape of the excitation coil 3 can be prevented from changing over time. Since the change in the output light flux of the bulb 4 can be reduced and the distance between the bulb 4 and the excitation coil 3 can be shortened, the luminous efficiency can be increased by increasing the magnetic coupling between the two.

The sectional shape of the excitation coil 3 is shown in FIG.
As shown in (a) and (b), since the shape is a polygonal flat shape such as an ellipse and a rhombus, the surface area of the excitation coil 3 is increased, so that the heat radiation effect is increased and the excitation coil 3 is increased.
Temperature rise can be suppressed. Further, FIG.
By providing irregularities in the cross-sectional shape as described above, the surface area can be further increased, and the heat radiation effect is further improved.

(Second Embodiment) A second embodiment of the present invention will be described with reference to FIGS. FIG.
(A) shows an electrodeless discharge lamp 1 according to a second embodiment of the present invention, (a) is a configuration diagram of an excitation coil 3, and (b) is a bobbin attached to (a). Excitation coil 3
FIG. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. The configuration different from the first embodiment is that the excitation coil 3 is wound twice around the bulb 4 so that the short side of the cross section is substantially perpendicular to the direction of emission of one light from the bulb 4. It is a point.

According to the present embodiment, the excitation coil is wound so that the short side of the cross section of the excitation coil 3 is substantially perpendicular to the direction of emission of one light. Although the magnetic coupling is slightly reduced, the shielding of the output luminous flux by the excitation coil 3 can be suppressed smaller than in the first embodiment. Further, as shown in FIG. 4B, the excitation coil 3 is held by the bobbin 5, and the bobbin cover 5a is attached to the bobbin 5, so that the excitation coil 3
Can be more reliably maintained.

(Third Embodiment) A third embodiment of the present invention will be described with reference to FIGS. FIG. 5 is an external view of the excitation coil 3 according to the third embodiment of the present invention. FIGS. 6A and 6B show the electrodeless discharge lamp 1 according to the embodiment, wherein FIG. 6A is a configuration diagram of the excitation coil 3 and FIG. 6B is a configuration diagram of the excitation coil 3 in which a bobbin is attached to FIG. It is. 7A and 7B show an electrodeless discharge lamp 1 according to the embodiment, wherein FIG. 7A is a configuration diagram of an excitation coil 3 having three windings, and FIG. 7B is an excitation coil in which a bobbin is attached to FIG. 3
FIG. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. The configuration different from that of the first embodiment is that the excitation coil 3 is arranged at least at the closest part of the bulb 4 so that the cross-sectional direction is substantially perpendicular to the light emission direction, and the cross-sectional shape is flat on the outside. The two points are that they are arranged so that the direction is substantially parallel to the light emission direction, and that the number of turns of the excitation coil 3 is increased to three.

In the present embodiment, the excitation coil 3 is arranged at least at the closest part of the bulb 4 so that the long side of the cross section is substantially perpendicular to the direction of emission of one light.
Outside, the excitation coil 3 is arranged such that the short side of the cross section is substantially perpendicular to the emission direction of one light.
Compared to the second embodiment, the magnetic coupling between the bulb 4 and the excitation coil 3 can be further increased, and the luminous efficiency can be increased. Further, by using the bobbin 5 as shown in FIG. 6B, the excitation coil 3 can be easily held.

When the number of turns of the excitation coil 3 is increased to three as shown in FIG. 7A, the output light flux is slightly larger than when the number of turns is two as shown in FIG. Although reduced, the magnetic coupling between the valve 4 and the excitation coil 3 can be increased. Also, as shown in FIG. 7 (b), the excitation coil 3 is molded with resin
And the change of the output light beam of the bulb 4 can be reduced.

(Fourth Embodiment) A fourth embodiment of the present invention will be described with reference to FIG. FIG. 8 shows an electrodeless discharge lamp 1 according to a fourth embodiment of the present invention.
(A) is a configuration diagram of the excitation coil 3, (b) is the excitation coil 3
FIG. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. A configuration different from the first embodiment is that flat conductors 7a and 7b are mounted on both surfaces of an insulator 6 as shown in FIG. 8, and one side of the conductor 7a and one side of the conductor 7b are connected and wound. The point is that the excitation coil 3 is formed several times.

In this embodiment, flat conductors 7a and 7b are mounted on both surfaces of the insulator 6, and one side of the conductor 7a and one side of the conductor 7b are connected to form the excitation coil 3 having two turns. Therefore, the trouble of winding the excitation coil 3 can be omitted, the shape of the excitation coil 3 can be prevented from changing over time, and the output characteristic of the valve 4 can be suppressed from changing.

The insulator 6 is a printed circuit board and the conductor 7
a and 7b may be patterns on a printed circuit board.

(Fifth Embodiment) A fifth embodiment of the present invention will be described with reference to FIG. FIG. 9 shows an electrodeless discharge lamp 1 according to a fifth embodiment of the present invention,
(A) is a configuration diagram of the excitation coil 3, (b) is the excitation coil 3
FIG. 3C is an upper sectional view of the excitation coil 3.
The same components as those of the fourth embodiment are denoted by the same reference numerals, and description thereof is omitted. A configuration different from the fourth embodiment is that flat conductors 7a, 7b, and 7c are mounted in an insulated state inside an insulator 6 as shown in FIG.
And one of the conductors 7b and the other of the conductors 7b and the conductor 7c
Is connected to each other to form the excitation coil 3 having three turns.

In this embodiment, flat conductors 7a, 7b and 7c are mounted inside the insulator 6 in an insulated state, respectively, and one of the conductors 7a and one of the conductors 7b and the other of the conductor 7b and one of the conductors 7c are mounted. Are connected to each other to form the excitation coil 3 having three turns, so that the excitation coil 3 is easily fixed,
The shape of the excitation coil 3 can be prevented from changing over time, and the change in the output characteristics of the valve 4 can also be suppressed.

Note that the insulator 6 may be a multilayer printed circuit board, and the conductors 7a, 7b and 7c may be patterns on the printed circuit board.

[0033]

As described above, the present invention has the following effects.

According to the first aspect of the present invention, the valve,
In an electrodeless discharge lamp composed of an excitation coil arranged close to the outer periphery of the bulb, the cross section of the excitation coil is flat, so that the surface area of the excitation coil increases, so that the heat radiation effect increases and the temperature of the excitation coil rises. Has the effect of being able to deter. In addition, since the excitation coil is wound around the bulb along the direction of emission of one light from the bulb, even if the number of windings of the excitation coil is increased, it is possible to prevent the output coil from being blocked by the excitation coil. There is also an effect.

According to the second aspect of the present invention, in the first aspect of the present invention, the excitation coil is wound so that the long side of the cross section of the excitation coil is substantially perpendicular to the direction of emission of one light. By shortening the distance between the bulb and the excitation coil and increasing the magnetic coupling between the two, the luminous efficiency can be increased. In addition, since the spread of the excitation coil in the light emission direction is reduced, the electrodeless discharge lamp itself can be made compact, and the degree of freedom in designing a lighting fixture that houses the electrodeless discharge lamp can be increased. There is also.

According to the third aspect of the present invention, in the first aspect of the present invention, the excitation coil is wound so that the short side of the cross section of the excitation coil is substantially perpendicular to the emission direction of one light. In addition, there is an effect that the shielding of the output light beam by the excitation coil can be further reduced.

According to the fourth aspect of the present invention, the excitation coil is arranged so that the long side of the cross section is substantially perpendicular to the direction of emission of one light at least at the closest part of the bulb. On the outside, the excitation coil is arranged so that the short side of the cross section is substantially perpendicular to the emission direction of one light, so that the shielding of the output luminous flux by the excitation coil is reduced and the magnetic coupling between the valve and the excitation coil is high. And the luminous efficiency can be increased.

According to the fifth aspect of the present invention, in the first aspect of the present invention, since the flat shape of the cross section of the excitation coil is a polygon or an ellipse, the surface area of the excitation coil is increased and the heat radiation effect is improved. Accordingly, there is an effect that the temperature rise of the excitation coil can be suppressed.

According to the sixth aspect of the present invention, in the invention of the fifth aspect, in the cross section of the excitation coil, irregularities are provided on a polygonal or elliptical outer periphery, so that the surface area of the excitation coil is further increased. There is an effect that the heat radiation effect is improved and the temperature rise of the excitation coil can be further suppressed.

According to the seventh aspect of the present invention, in the fifth aspect of the present invention, since the polygon is a quadrangle, the surface area of the excitation coil is widened and the heat radiation effect is increased, thereby suppressing the temperature rise of the excitation coil. There is an effect that can be.

According to the eighth aspect of the present invention, in the first aspect of the present invention, since the excitation coil is manufactured by molding, there is an effect that the excitation coil can be easily wound.

According to the ninth aspect of the present invention, in the first aspect of the present invention, since the holding mechanism for accommodating the excitation coil is provided, the excitation coil can be easily fixed and the shape of the excitation coil can be changed with time. Thus, there is an effect that the change of the output light flux of the bulb can be suppressed and the change of the output light flux of the bulb can be reduced.

According to the tenth aspect, the ninth aspect is provided.
In the described invention, since the holding mechanism is a bobbin structure having a groove, it is possible to easily fix the excitation coil, suppress a change with time of the shape of the excitation coil, and reduce a change in the output light flux of the bulb. There is an effect that can be.

According to the eleventh aspect, the ninth aspect is provided.
In the described invention, the holding mechanism is formed by integrally molding the excitation coil and the resin, so that the excitation coil can be easily fixed and the shape of the excitation coil can be further suppressed from changing over time. There is an effect that a change in the output light beam can be reduced.

According to the twelfth aspect of the present invention, a plasma discharge is generated inside the bulb by energizing a high-frequency current through the bulb, and an excitation coil disposed close to the outer periphery of the bulb. In an electrodeless discharge lamp to be lit, the excitation coil has a flat shape, is wound several times in the direction of light emission from the bulb, and is wound in a direction perpendicular to the flat direction of the cross section to be wound. Since the holding mechanism for storing is provided, there is an effect that the heat radiation effect is increased by increasing the surface area of the excitation coil, and the temperature rise of the excitation coil can be suppressed. Further, there is an effect that the light blocking of the output light beam can be suppressed small and the change of the output light beam of the bulb can be reduced.

[Brief description of the drawings]

FIGS. 1A and 1B are configuration diagrams of an electrodeless discharge lamp according to a first embodiment of the present invention, wherein FIG. 1A is a circuit diagram and FIG.

FIG. 2 is a configuration diagram of an electrodeless discharge lamp according to a first embodiment of the present invention, in which (a) and (b) are cross-sectional views.

FIG. 3 is a cross-sectional view of an excitation coil according to the first embodiment of the present invention.

FIG. 4 is a configuration diagram of an electrodeless discharge lamp showing a second embodiment of the present invention, and (a) and (b) are cross-sectional views.

FIG. 5 is an external view of an excitation coil according to a third embodiment of the present invention.

FIG. 6 is a configuration diagram of an electrodeless discharge lamp showing a third embodiment of the present invention, and (a) and (b) are cross-sectional views.

FIG. 7 is a configuration diagram of an electrodeless discharge lamp showing a third embodiment of the present invention, and (a) and (b) are cross-sectional views.

FIG. 8 is a configuration diagram of an electrodeless discharge lamp showing a fourth embodiment of the present invention, (a) is a cross-sectional view of an excitation coil,
(B) is an external view.

FIGS. 9A and 9B are configuration diagrams of an electrodeless discharge lamp showing a fifth embodiment of the present invention, wherein FIG. 9A is a sectional view, FIG. 9B is an external view, and FIG. is there.

FIG. 10 is a configuration diagram showing a conventional technique 1.

FIG. 11 is a configuration diagram showing a conventional technique 1.

FIG. 12 is a configuration diagram showing a conventional technique 2.

FIG. 13 is a configuration diagram showing a conventional technique 3.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 electrodeless discharge lamp 2 high frequency power supply 3 excitation coil 4 bulb 5 bobbin 5a bobbin lid 5b resin 6 insulator 7a conductor 7b conductor 7c conductor

Claims (12)

[Claims] 1. An electrodeless discharger comprising: a bulb; and an excitation coil disposed close to the outer periphery of the bulb, wherein a high-frequency current is applied to the excitation coil to generate a plasma discharge inside the bulb and turn on the bulb. In an electric lamp, the excitation coil has a flat cross section, and is wound around the bulb along a direction in which one light is emitted from the bulb. 2. The electrodeless discharge lamp according to claim 1, wherein said excitation coil is wound such that a long side of a cross section of said excitation coil is substantially perpendicular to a direction in which one light is emitted. 3. The electrodeless discharge lamp according to claim 1, wherein the excitation coil is wound so that a short side of a cross section of the excitation coil is substantially perpendicular to a direction in which one light is emitted. 4. The excitation coil is arranged so that a long side of a cross section is substantially perpendicular to a light emission direction of one light at least at a closest portion of the bulb, and a short side of a cross section is outside the bulb. 2. The electrodeless discharge lamp according to claim 1, wherein the excitation coil is disposed so as to be substantially perpendicular to a direction of emission of one light. 5. The electrodeless discharge lamp according to claim 1, wherein a flat shape of a cross section of the excitation coil is a polygon or an ellipse. 6. The electrodeless discharge lamp according to claim 5, wherein in the cross section of the excitation coil, irregularities are provided on an outer periphery of the polygon or the ellipse. 7. The electrodeless discharge lamp according to claim 5, wherein in the cross section of the excitation coil, the polygon is a quadrangle. 8. The electrodeless discharge lamp according to claim 1, wherein the excitation coil is formed by molding. 9. An electrodeless discharge lamp according to claim 1, further comprising a holding mechanism for accommodating said excitation coil. 10. The electrodeless discharge lamp according to claim 9, wherein said holding mechanism has a bobbin structure having a groove. 11. The electrodeless discharge lamp according to claim 9, wherein said holding mechanism is formed by integrally molding said excitation coil and resin. 12. An electrodeless device comprising a valve and an excitation coil disposed close to the outer periphery of the valve, and applying a high-frequency current to the excitation coil to generate a plasma discharge inside the valve and turn on the electrode. In the discharge lamp, the excitation coil has a flat cross section, and along the radiation direction of one light from the bulb, a long side of the cross section of the excitation coil becomes substantially perpendicular to the radiation direction of one light. The electrodeless discharge lamp further includes a holding mechanism wound around the bulb so as to house the excitation coil.