JP3674712B2 - Halogen bulb, halogen bulb with reflector, and lighting device - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a halogen bulb having a bulb shape capable of efficiently reflecting infrared rays to a filament by a visible light transmitting infrared reflecting film, a halogen bulb with a reflecting mirror, and an illumination device.
[0002]
[Prior art]
Conventionally, this type of halogen light bulb is disclosed in Japanese Patent Application Laid-Open No. 4-47660 (hereinafter referred to as “conventional example”), and this light bulb will be described with reference to FIGS. The halogen bulb 121 has a glass bulb 122 formed in a spheroid, and a filament 123 having a length equivalent to the distance between two focal points of the spheroid is arranged in the bulb 122. At the same time, a small amount of halide is enclosed.
[0003]
A visible light transmitting infrared reflecting film 124 that transmits visible light and reflects infrared light is formed on the outer surface of the spheroid of the bulb 122. As a result, visible light of the light emitted from the filament 123 is transmitted, and infrared rays are returned to the filament 123 in the bulb 122 to heat it, thereby improving efficiency. Reference numeral 125 denotes a base, and the crosses in the bulb 122 are the two focal points 120 of the bulb 122.
[0004]
JP-A-5-144419 also discloses a similar halogen bulb. This light bulb will be described with reference to FIG. A visible light transmitting / infrared reflecting film 124 is formed on the entire outer surface of the glass bulb 122 having a spherical portion 122a and a tubular portion 122c, and a filament 123 is disposed therein. According to this, there is a description that the infrared ray reflected from the spherical portion 122a to the filament 123 increases and the infrared ray transmitted outside the glass bulb 122 decreases.
[0005]
[Problems to be solved by the invention]
However, in the case where the bulb 122 is formed in a spheroid, if the length of the filament 123 exceeds the distance between the two focal points 120 of the spheroid, the length of the filament 123 is accommodated. Accordingly, it is necessary to increase the outer shape of the bulb 122 in proportion to the increase in the outer size of the halogen bulb 121, and the infrared rays reflected by the infrared reflecting film 124 enter the filament 123 near the two focal points 120. Reflected in a concentrated manner, an abnormally high temperature hot spot appears on the filament 123 and, for example, tungsten, which is a filament material, concentrates and evaporates, and a thinning phenomenon occurs in this portion. There is a problem that the life of the halogen bulb 121 may be shortened.
[0006]
As a countermeasure, it is conceivable that the length of the filament 123 is made shorter than the distance between the two focal points 120. In this case, however, the light emitted from the left end portion of the filament 123 as shown by the light ray d in FIG. Among them, when infrared rays are incident on the end 122 b of the bulb 122, there is a problem that the infrared rays reflected by the infrared reflecting film 124 do not return to the filament 123 as indicated by the light beam da.
[0007]
In addition, in the halogen bulb 121 having the spherical portion 122a and the tubular portion 122c disclosed in FIG. 13, the infrared light transmitted to the outside of the bulb 122 is reduced, but the light radiated from the filament 123 enters the tubular portion 122c. There is a problem that the angle increases and infrared rays are transmitted from the bulb 122 to the outside of the bulb 122 instead of returning to the filament 123.
[0008]
Incidentally, the amount of infrared rays absorbed by the filament 123 depends on the absorption rate ε (feedback rate). In general, in this type of halogen light bulb, about half of the reflected light to the filament 123 is re-reflected by the filament 123. Therefore, when there is infrared light that does not return to the filament 123, there is a gap between the infrared reflective film 124 and the filament 123. In this case, the infrared rays that are reflected a plurality of times and absorbed by the filament 123 are also eliminated, so that the efficiency cannot be improved by increasing the absorption rate.
[0009]
Thus, it is conceivable to increase the length of the filament 123 in the bulb 122 and increase the total amount of infrared absorption, thereby improving the efficiency. However, as described above, the external dimensions of the halogen bulb cannot be reduced. . Furthermore, when designing the shape of a dichroic mirror, a lighting fixture or the like so as to obtain a desired light distribution, the light source is often regarded as a point light source, and therefore the light distribution is close to the design value. In order to obtain things, it is required to reduce the size of the halogen bulb filament.
[0010]
Accordingly, the present invention has been made in view of such circumstances, and provides a halogen bulb, a halogen bulb with a reflector, and a lighting device that can improve efficiency by increasing the absorption rate of infrared rays into a filament. For the purpose.
[0011]
[Means for Solving the Problems]
The invention of claim 1 is a virtual ellipse having two focal points.A valve having a spheroid part having substantially the same shape as the body, and a bulging part formed so that the ratio of the major axis length to the minor axis length gradually decreases from the center toward the major axis end part And a visible light transmitting infrared reflecting film formed on the outer surface of the spheroid and bulge of the bulb;In this valveOf the virtual ellipsoidA filament disposed between the two focal points and having a coil length equal to or shorter than the distance between the focal points; and a visible light transmitting infrared reflecting film formed on an inner surface or an outer surface of the bulb.The invention of claim 2 has a spheroid part having substantially the same shape as a virtual spheroid obtained by rotating a virtual ellipsoid having two focal points around the major axis, and at least one end part in the direction of the major axis end part. A bulb having a bulging portion having a shape such that an incident angle at which infrared rays from a filament are incident is smaller than that of a virtual spheroid;
A filament disposed between two focal points of a virtual ellipsoid in the bulb and having a coil length equal to or shorter than the distance between the focal points; a visible light transmitting infrared reflecting film formed on the spheroid and bulge of the bulb; Comprising.Here, the virtual spheroid is not actual, but is obtained by rotating an ellipse expressed on a design drawing or the like 360 ° around the major axis as a rotation axis when manufacturing a bulb. Conversely, by projecting a bulb, the ellipse that is the basis of the virtual spheroid can be represented on the drawing or the like. Focus is the basis of this virtual spheroidVirtualellipsebodybelongs to. The short axis and long axisVirtualellipsebodyAn axis that passes through the center and is orthogonal. The minor axis direction means the direction perpendicular to the major axis, and the major axis direction means the direction perpendicular to the minor axis..
[0012]
Claim3The invention of claim 1Or 2In this invention, the sealing part is formed in the both ends of the major axis direction of the valve.
[0013]
Claim4The invention of claim 1Or 2In the invention, a leg is provided at both ends of the filament, and the leg portions are respectively disposed at the two focal points.
[0014]
Claim5The invention of claim 1Or 2In this invention, the bulging portion is formed by a combination of curved surfaces having a plurality of curvatures. In other words, the bulging portion deviates from the shape of the virtual spheroid and has a shape bulging outward. This shape is obtained by rotating a curve formed by a combination of curved surfaces having a plurality of curvatures around the major axis.
[0015]
Claim6The invention of claim 1Or 2In the invention, when the length of the filament is Cl and the distance between the two focal points is l, Cl / l = 0.6 to 1.0. This is to prevent a hot spot from being easily formed at the end of the filament, thereby shortening the lifetime and reducing the infrared absorption rate ε (feedback rate) to the filament.
[0016]
Claim7The invention of claim 1Or 2In this invention, the bulging part is a part of a spherical surface, and when the length of the filament is Cl and the distance between two focal points is 1, Cl / l = 0.4 to 1.0. . This is to prevent a hot spot from being easily formed at the end of the filament, thereby shortening the lifetime and reducing the infrared absorption rate ε (feedback rate) to the filament.
[0018]
Claim8The invention of claim 1Or 2This is a combination of a halogen bulb and a reflecting mirror. The combination structure may be anything such as a structure in which both are fixed with an adhesive or the like, a structure in which a cap or a pin of a light bulb is inserted and fixed in a socket provided in a reflecting mirror or the like. Claim9The invention of claim 1Or 2The halogen light bulb according to the invention is incorporated in a lighting fixture body. The structure of the above combination may be anything such as a structure in which a cap or a pin of a light bulb is inserted and fixed in a socket provided in the luminaire body.
[0019]
[Action]
Claim1 or 3In the invention,The shape of the bulb has a spheroid and a bulging portion formed so that the ratio of the major axis length to the minor axis length gradually decreases as it goes in the direction of the major axis end. The direction is formed in a shape close to a sphere. For this reason, the infrared light that has entered the bulging part is reflected by the visible light transmitting infrared reflecting film, or is repeatedly reflected and returned to the spheroid, where further the visible light transmitting infrared reflecting film and the filament are In the meantime, reflection is repeated, and in the meantime, the infrared rays are absorbed by the filament, and the efficiency can be increased. In the invention of claim 2 or 3, the bulb has a virtual spheroid and an incident angle at which infrared rays from the filament are incident is smaller than that of the virtual spheroid at least at one end in the direction of the major axis. The incident angle of the infrared rays incident on the bulge is smaller than a part of the virtual spheroid, and is reflected in the filament direction accordingly, Returned to this.
[0020]
Claim4In the present invention, there are legs at both ends of the filament, and these leg portions are respectively arranged at the two focal points. Therefore, these portions are further heated, and are generated between the filament end portion and the center portion. The temperature difference can be relaxed, the generation of internal stress of the filament due to thermal strain can be suppressed, and the lifetime can be shortened and the deformation of the filament during lighting can be prevented.
[0021]
Claim5In the invention, the bulging portion has a shape existing outside the virtual spheroid by a combination of curved surfaces having a plurality of curvatures, and an incident angle of infrared rays incident on this portion isVirtualIt becomes smaller than a part of the spheroid, and is reflected in the filament direction accordingly and returned to it.
[0022]
Claim6In this invention, when the length of the filament is Cl and the distance between the two focal points is l, Cl / l = 0.6 to 1.0, and the infrared light incident on the bulging part also returns to the filament. Also, hot spots are less likely to occur.
[0023]
Claim7In this invention, the bulging part is a part of a spherical surface, and when the length of the filament is Cl and the distance between two focal points is 1, Cl / l = 0.4 to 1.0. Infrared rays incident on the bulging part also return to the filament and hot spots are less likely to occur.
[0025]
In the invention of claim 8, the infrared ray radiated from the halogen bulb is reflected in the filament direction without leakage by the infrared reflecting film, and the visible light is transmitted and reflected by the reflecting mirror.
[0026]
According to the ninth aspect of the present invention, the infrared ray radiated from the halogen bulb is reflected by the infrared reflecting film in the filament direction without leakage, and the visible light is transmitted and reflected by the luminaire main body.
[0027]
【Example】
A first embodiment of the halogen bulb of the present invention will be described with reference to FIGS. The valve 1 is filled with an inert gas and a small amount of halide, and is sealed by a pair of left and right sealing portions 2a and 2b. The sealing portions 2a and 2b are formed to be solid flat by crushing the outer end portions of a pair of cylindrical portions 3a and 3b integrally coupled to both ends in the long axis direction of the valve 1, and embedded with molybdenum foils 4a and 4b. doing. A pair of lead wires 6a and 6b connected to both ends of the filament 5 are led out to the outside through the molybdenum foils 4a and 4b, and are held and fixed to the caps 7a and 7b.
[0028]
Here, the shape of the valve 1 will be described. The bulb 1 is formed with a visible light transmitting infrared reflecting film 10 in the short axis direction in the center between the focal points of a virtual spheroid 9 obtained by rotating a virtual ellipsoid having two focal points 8a and 8b around the major axis. The surface of the spheroid 1c has substantially the same shape as the virtual spheroid 9, and visible light in the short axis direction at both ends of the major spheroid 9 is at least one end in the major axis direction. The shape of the surface on which the transmissive infrared reflective film 10 is formed is composed of spherical portions 1 a and 1 b that are bulged portions that are shapes existing outside the virtual spheroid 9. This is because the spheroid 1c is formed so that the ratio of the major axis length / minor axis length gradually decreases as it goes to both ends in the major axis direction, and is formed in the spherical parts 1a, 1b close to the hollow hemisphere. Yes.
[0029]
Accordingly, the length in the short axis direction becomes longer than the shape of the virtual spheroid 9 shown by the alternate long and short dash line in FIG. 1 as it goes to both ends in the long axis direction of the bulb 1, so that the outer peripheral surfaces of these spherical portions 1a and 1b The angle formed by the tangent line in contact with the valve is steeper than that at both ends in the long axis direction of the bulb 1. The filament 5 is disposed between the two focal points 8a and 8b of the spheroid 1c, and the length Cl of the filament 5 is formed to be equal to or less than the distance l between the two focal points 8a and 8b, and Cl / l = 0. .6 to 1.0. This is because when Cl / l exceeds 1, a hot spot is relatively easily formed at the end of the filament 5 and the life becomes short, and as shown in the experimental data A shown in FIG. This is to prevent the absorptivity ε (feedback rate) of the filament 5 from decreasing when the ratio is less than .6.
[0030]
By the way, the virtual spheroid 9 does not have a substance, and is expressed on a design drawing or the like when the valve 1 is manufactured.VirtualellipsebodyIs obtained by rotating 360 ° with the long axis as the rotation axis. On the contrary, a bulb such as a halogen bulb is projected and becomes the basis of the virtual spheroid 9VirtualellipsebodyCan also be expressed on a drawing or the like. The focal point is the basis of this virtual spheroid 9Virtualellipsebodybelongs to. The short axis and long axisVirtualellipsebodyAn axis that passes through the center and is orthogonal. The minor axis direction refers to the direction perpendicular to the major axis, and the major axis direction refers to the direction perpendicular to the minor axis. Further, the bulging part that is a shape existing outside the virtual spheroid 9 is a virtual ellipse in the short axis direction centered between the focal points by projecting a bulb.bodyThe surface where the visible light transmitting infrared reflecting film of the bulb is formed outside the virtual ellipse is present at both ends in the major axis direction.
[0031]
A visible light transmitting infrared reflecting film 10 that transmits visible light and reflects infrared rays is formed on almost the entire outer surface of the spheroid 1c including at least the left and right spherical portions 1a and 1b of the bulb 1. The infrared reflecting film 10 is formed by laminating a thin film H having a high refractive index made of, for example, TiO2 and a thin film L having a low refractive index made of, for example, SiO2 in, for example, a multilayer of 12 layers. Of these, visible light is transmitted and radiated to the outside, while infrared light is reflected and returned to the filament 5 to be heated, thereby improving efficiency.
[0032]
Therefore, when the infrared rays are incident on the spherical portions 1a and 1b among the light radiated from the left end portion of the filament 5 as in the light ray d in FIG. 1, the reflection angle reflected by the infrared reflecting film 10 is changed. Reflected to deviate in the opposite direction. For this reason, the infrared rays incident on the spherical portions 1a and 1b are reflected here, and then returned to the filament 5 in the spheroid portion 1c to absorb the infrared rays, as shown by the light ray db. The amount increases gradually and the efficiency improves.
[0033]
By the way, among the infrared rays reflected by the infrared reflection film 10 and returned to the filament 5, the amount absorbed by the filament 5 depends on the infrared absorption rate ε, and almost half or more of the incident light to the filament 5 is absorbed, The rest is reflected.
[0034]
Therefore, the infrared rays that do not return to the filament 5 are reduced and almost returned to the filament 5, so that the efficiency is improved accordingly. In addition, since infrared rays are returned to the filament 5 regardless of which part of the infrared reflecting film 10 is incident, the infrared rays reflected between the infrared reflecting film 10 and the filament 5 a plurality of times are almost returned to the filament 5. , The efficiency is improved accordingly.
[0035]
As a result, even if the length of the filament 5 is short, the absorption rate of infrared rays is not reduced, the filament 5 can be shortened, and the bulb 1 incorporating the filament 5 can be downsized. In addition, a short life can be prevented.
[0036]
For this reason, when the halogen bulb 11 is mounted on, for example, a bowl-shaped dichroic mirror, the filament bulb 5 can be shortened, so that the halogen bulb 11 can be handled as a point light source. The combination efficiency with can also be improved.
[0037]
FIG. 3 shows a comparison between the lamp characteristics of the halogen bulb 11 of the first embodiment and the lamp characteristics of the halogen bulbs of the conventional examples 1 and 2, and the halogen bulb 11 of the present invention is more in comparison with the clear lamp. It was more efficient than the halogen bulb 121 of the conventional example. That is, in the halogen bulb 121 of Conventional Example 1, the major axis of the spheroid bulb 122 is 11.4 mm (major axis length is 22.8 mm), the minor axis is 7.0 mm (minor axis length is 14.0 mm), The efficiency improvement rate is 23.1% with respect to the clear lamp in which the filament 123 has a length of 18 mm and no infrared reflecting film is formed on the outer surface of the transparent bulb. Further, Conventional Example 2 shows a halogen light bulb in which only the length of the filament 123 of Conventional Example 1 is shortened to 11 mm, and the efficiency improvement rate is 17.6%.
[0038]
In contrast, in the halogen bulb 11 of the first embodiment, the major axis of the center part of the spheroid 1c of the bulb 1 shown in FIG. The major diameter of both spherical parts 1a and 1b is 8.0 mm, the minor diameter is 6.6 mm, the filament length is 11 mm, and the efficiency improvement rate is 24.4%.
[0039]
Therefore, as apparent from FIG. 3, the efficiency of the first embodiment is about 6.8% higher than that of the conventional example 2 in which the filament length is equal. Although the efficiency improvement rate is only slightly high, the length of the filament is as short as about 7 mm, so that the valve can be downsized. That is, in the first embodiment, the size can be reduced without reducing the efficiency.
[0040]
In the first embodiment, the case where the present invention is applied to the double-ended halogen light bulb 11 has been described. However, the present invention is not limited to this, and for example, as shown in FIG. It can also be applied to other halogen bulbs. In this halogen bulb, according to FIG. 5B, which is an enlarged view of the main part, the connection structure between the filament 5 formed of a double coil and the lead wires 6a and 6b is a single unit formed at both ends of the filament 5. The legs 5a and 5b made of a coil (single coil) are caulked with lead wires 6a and 6b to be joined. At this time, since the two focal points 8a and 8b are arranged on the legs 5a and 5b, this portion is further heated. Accordingly, the temperature difference generated between the end portion and the center portion of the filament 5 can be relaxed, the generation of internal stress of the filament 5 due to thermal strain can be suppressed, and the lifetime of the filament 5 can be shortened and the filament 5 can be lit. Deformation can be prevented.
[0041]
Next, a halogen light bulb showing a second embodiment of the present invention will be described with reference to FIGS. 4 and 6 to 8. If the configuration is the same as that of the first embodiment, the description thereof is omitted. In FIG. 6, the difference between the first embodiment is the shape of the bulb 1, and this shape will be described. This bulb 1 is obtained by rotating a virtual ellipsoid having two focal points 8a and 8b around the major axis. The surface of the virtual spheroid 9 on which the visible light transmitting infrared reflecting film 10 in the short axis direction in the center between the focal points is formed is substantially the same shape as the virtual spheroid 9, and the spheroid 1c is a virtual rotation. A hollow that is a bulging portion in which the shape of the surface on which the visible light transmitting infrared reflecting film 10 in the short axis direction is formed at both ends of the ellipsoid 9 in the major axis direction is a shape existing outside the virtual spheroid 9 It consists of hemispherical parts 1a and 1b. The bulb 1 is integrally connected in an outwardly convex semispherical shape at both ends in the long axis direction to form an upper spherical portion 1a and a lower spherical portion 1b, and these spherical portions 1a and 1b are formed into rotational ellipses. The body part 1c is integrally coupled. Here, the hemisphere does not indicate only half of a hollow sphere, but also includes a part of a sphere less than that.
[0042]
Therefore, since the length in the minor axis direction becomes longer than the conventional one as it goes to both ends in the major axis direction of the valve 1, the angle formed by the tangents contacting the outer peripheral surfaces of these spherical portions 1 a and 1 b is the major axis of the valve 2. It is steeper than those at both ends. The bulb 1 is formed as a spheroid, and a filament 5 is disposed between the two focal points 8a and 8b. The length Cl of the filament 5 is formed slightly shorter than the distance l between the two focal points 8a and 8b, and is set to Cl / l = 0.4 to 1.0. This is because when Cl / l exceeds 1, the lifetime becomes short, and as shown in the experimental data B shown in FIG. 4, when Cl / l is less than 0.4, the absorption rate (feedback rate) of the filament 5 decreases. This is to prevent this.
[0043]
FIG. 7A shows a modification of the second embodiment of the present invention, and is a front view of the main part of a halogen bulb 21 of JD110V85W. The halogen bulb 21 is a long axis of a spheroid transparent glass bulb 1. One feature is that one end portion in the direction, for example, one end portion on the top portion side, is integrally coupled in an outwardly convex hemisphere to form the spherical portion 1a. Therefore, since one end portion of the bulb 1 is formed in the spherical portion 1a, the efficiency can be improved by the amount that the infrared ray reflected by the spherical portion 1b can be returned to the filament 5.
[0044]
FIG. 7B is also a front view of an essential part of a halogen bulb 31 showing a modification of the second embodiment. The halogen bulb 31 is one end in the major axis direction of the spheroid transparent glass bulb 1. One of the parts, for example, one end part on the top part side is formed as an outwardly projecting spherical part 1a, while the other end part on the sealing part 1b side is formed in a cylindrical shape. Also in this halogen bulb 31, one end of the spheroid bulb 1 is formed in the spherical portion 1a, so that the efficiency can be improved by the amount that infrared rays reflected by the spherical portion 1a can be returned to the filament. it can.
[0045]
FIG. 8 compares the lamp characteristics of the halogen bulbs of the second embodiment and the modified example with the conventional example 1 and the clear conventional product in the case where the infrared reflecting film 4 is not formed on the outer surface of the transparent bulb 2. As shown, the luminous flux per unit W (1 m / W) was superior to the conventional example 1 and the clear conventional product in the second embodiment of the present invention and was more efficient. The clear conventional product shows the lamp characteristics when the bulb is formed in a cylindrical shape with a diameter of 11 mm using transparent glass. On the other hand, in the halogen bulb of the conventional example and the second embodiment of the present invention, the length of the filament 5 is 10 mm, the coil diameter is 1.6 mm, the major axis is 18 mm, the radius of the spherical portion 1a is 5.5 mm, The lamp characteristics are shown when the width of the stop 1b is 10.5 mm.
[0046]
Next, a third embodiment of the present invention will be described with reference to FIG. This halogen lamp with a reflector is mainly composed of a halogen lamp 11, a reflecting mirror 12 on which an optical interference film for transmitting infrared rays radiated from the halogen lamp 11 and reflecting visible light is formed, and both. 13 and a base portion 14 formed of ceramic that is held with 13 interposed therebetween. Further, a cover glass 15 is provided on the front surface of the reflecting mirror 12 as a countermeasure against accidental rupture of the halogen bulb 11.
[0047]
Therefore, the infrared rays emitted from the halogen bulb by the infrared reflecting film 10 are reflected in the direction of the filament 5 without leakage, and the visible light is transmitted and reflected by the reflecting mirror 12. The length of the filament 5 can be shortened by an amount corresponding to the improvement of the efficiency of the infrared feedback rate in the bulb 1, so that the bulb 1 can be reduced in size without reducing the efficiency, and the combination with the reflecting mirror 12 can be achieved. Efficiency can be increased.
[0048]
Next, the illuminating device which is 4th Example of this invention is demonstrated with reference to FIG. This illuminating device includes a luminaire main body 17 having a reflecting mirror 19 and a socket 16 and the like, and a halogen bulb 11. The halogen bulb 11 is supported and fixed by inserting lead pins 18 and 18 led out from the end portion into the socket 16.
[0049]
Therefore, the infrared rays radiated from the halogen bulb 11 are reflected by the infrared reflecting film 10 in the direction of the filament 5 without leakage, and the visible light is transmitted and reflected by the lighting fixture body 17. As the efficiency increases, the filament 5 can be shortened to be closer to the point light source, and the efficiency of the combination with the luminaire main body 17 can be improved.
[0050]
【The invention's effect】
Claim 1 to3The effect of the invention is that the part that incorporates the filament of the bulbWhile having a spheroid that is almost the same shape as the virtual spheroidThe bulging portion is formed by gradually decreasing the ratio of the major axis length to the minor axis length as going to at least one end portion in the major axis direction., And a bulging portion having a shape such that the incident angle at which the infrared rays from the filament are incident is smaller than that of the virtual spheroid is formed.Therefore, the amount of infrared rays reflected at the end in the major axis direction and returned to the filament increases, and the amount of infrared rays reflected between the infrared reflection film and the filament and absorbed by the filament increases. As a result, efficiency can be increased.
[0051]
Claim4The effect of the invention is that the filament has a pair of filament legs, and these leg portions are respectively disposed at the two focal points. Therefore, it is possible to alleviate the temperature difference generated in the light source, to suppress the generation of internal stress of the filament due to thermal strain, and to shorten the life and prevent filament deformation during lighting.
[0052]
Claim5The effect of the invention is that the amount of infrared rays reflected at the ends in the major axis direction and returned to the filament is increased by the bulging portion formed by a combination of curved surfaces having a plurality of curvatures. Since the amount of infrared rays reflected by the filament and absorbed by the filament increases, the efficiency can be increased. Claim6The effect of the invention is that when the length of the filament is Cl and the distance between the two focal points is l, Cl / l = 0.6 to 1.0, and the short life and absorption rate ε (feedback rate) are Reduction can be prevented.
[0053]
Claim7The effect of the invention is that the bulging part is a part of a spherical surface, and when the length of the filament is Cl and the distance between two focal points is l, Cl / l = 0.4 to 1.0 Therefore, it is possible to prevent a short life and a decrease in the absorption rate ε (feedback rate).
[0055]
Claim8The effect of the invention is that the infrared ray radiated from the halogen bulb is reflected in the filament direction without leakage by the infrared reflecting film, and the visible light is transmitted and reflected by the reflecting mirror. Since the efficiency of the infrared feedback rate in the bulb has been improved, the length of the filament has been shortened, so the bulb can be reduced in size without lowering the efficiency, and the combination efficiency with the instrument can be increased. it can.
[0056]
Claim9The effect of the invention is that the infrared ray radiated from the halogen bulb is reflected in the filament direction without leakage and the visible light is transmitted and reflected by the luminaire main body by the infrared reflecting film. As the efficiency increases, the length of the filament can be shortened to approach the point light source, and the efficiency of combining the lighting fixtures can be improved.
[Brief description of the drawings]
FIG. 1 is a front view of an essential part of a halogen bulb showing a first embodiment of the present invention.
FIG. 2 is a front view of a halogen bulb showing a first embodiment of the present invention.
FIG. 3 is a comparison diagram of lamp characteristics of the halogen bulb of the first embodiment of the present invention and the conventional example.
FIG. 4 is a graph showing experimental data of the halogen light bulbs according to the first and second embodiments of the present invention and showing infrared absorptance.
FIG. 5A is a front view of a halogen bulb showing a modification of the first embodiment of the present invention. (B) is an enlarged view of the main part.
FIG. 6 is a front view of a halogen bulb showing a second embodiment of the present invention.
FIGS. 7A and 7B are front views of essential parts of a halogen bulb showing a modification of the second embodiment of the present invention.
FIG. 8 is a comparison diagram of lamp characteristics of the halogen bulbs of the second embodiment of the present invention and the conventional example.
FIG. 9 is a side view, partly in section, of a halogen bulb with a reflector, showing a third embodiment of the present invention.
FIG. 10 is a side view, partly in section, of a lighting device showing a fourth embodiment of the present invention.
FIG. 11 is a front view of a halogen bulb showing a conventional example.
FIG. 12 is a main part schematic diagram for explaining the operation of a conventional example.
FIG. 13 is a longitudinal sectional view of a conventional halogen bulb.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Valve | bulb, 1a, 1b ... Swelling part (spherical part), 1c ... Spheroid part,
2a, 2b ... sealing part, 5 ... filament, 8a, 8b ... focal point,
9 ... virtual spheroid, 10 ... visible light transmitting infrared reflecting film,
11 ... Halogen bulb.

Claims (9)

A spheroid having substantially the same shape as a virtual spheroid obtained by rotating a virtual ellipsoid having two focal points around the major axis, and a major axis length and a minor axis extending from the center toward the major axis end. A valve having a bulge formed to gradually reduce the ratio to the length;
A visible light transmitting infrared reflecting film formed on the spheroidal part and the bulging part of the bulb;
A filament disposed between the two focal points of a virtual ellipsoid in the bulb and having a coil length less than or equal to the distance between the focal points;
A halogen bulb characterized by comprising: Infrared light from the filament is incident on at least one end in the direction of the long diameter end, and has a spheroid that is substantially the same shape as a virtual spheroid obtained by rotating a virtual ellipsoid having two focal points around the major axis. A bulb having a bulging portion having a shape such that the incident angle to be smaller than the virtual spheroid;
A filament disposed between the two focal points of a virtual ellipsoid in the bulb and having a coil length less than or equal to the distance between the focal points;
A visible light transmitting infrared reflecting film formed on the spheroid and bulge of the bulb;
A halogen bulb characterized by comprising: The halogen bulb according to claim 1 or 2, wherein sealing portions are formed at both ends of the bulb in the long axis direction. The halogen light bulb according to claim 1 or 2, wherein a leg is provided at both ends of the filament, and the leg portions are respectively disposed at the two focal points. The halogen bulb according to claim 1 or 2, wherein the bulging portion is formed by a combination of curved surfaces having a plurality of curvatures. The halogen light bulb according to claim 4, wherein when the length of the filament is Cl and the distance between two focal points is l, Cl / l is 0.6 to 1.0. The bulging portion is a part of a spherical surface; when the length of the filament is Cl and the distance between two focal points is l, Cl / l = 0.4 to 1.0. Item 3. A halogen bulb according to item 1 or 2. Claim 1 or 2 halogen bulbs and described; halogen bulb with reflector, characterized by comprising; a reflecting mirror for reflecting visible light emitted from the halogen bulb. An illuminating device comprising: the halogen light bulb according to claim 1 ; and a lighting fixture main body to which the halogen light bulb can be attached.

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