WO2013037636A1

WO2013037636A1 - Auxiliary starter for lighting device and lighting device

Info

Publication number: WO2013037636A1
Application number: PCT/EP2012/066701
Authority: WO
Inventors: Hui Tang; Liuyu XU; Yongding YAN
Original assignee: Osram Ag
Priority date: 2011-09-16
Filing date: 2012-08-28
Publication date: 2013-03-21
Also published as: CN103000487A

Abstract

The present invention relates to an auxiliary starter for a lighting device and a lighting device. The auxiliary starter comprises a discharging vessel (11), a supporter (13) and a feeding device (15), wherein the discharging vessel (11) gas tightly encloses filling gas (12) and has at least one radiation transmission region, the supporter (13) is arranged in the discharging vessel (11) and is conductively connected to the feeding device (15) which passes through the discharging vessel (11), characterized in that the discharging vessel (13) has emitting material (14) for emitting electrons on the surface thereof.

Description

AUXILIARY STARTER FOR LIGHTING DEVICE AND LIGHTING DEVICE Field of the Invention

[0001] The present invention generally relates to the technical field of lighting, and in particular, to an auxiliary starter for a lighting device. Moreover, the present invention relates to a lighting device.

Background of the Invention

[0002] In the present field, it is known a metal halide lamp (HQI) and a ceramic metal halide lamp (HCI) with an auxiliary starter. If there is no auxiliary starter, the HQI and the HCI generally have a relative long ignition time. In order to resolve the difficulty of ignition of the HQI and the HCI, several methods are known in the prior art. One method is filling krypton 85 into a burner. However, the krypton 85 has radioactivity, which may cause damage to the environment and persons. Secondly, it is known in the prior art to employ the auxiliary starter (such as UV enhancer) in the HQI and the HCI to improve the ignition characteristic of this kind of lamp. The UV enhancer is typically a small discharge tube, which acts as an UV radiation source. Such UV enhancer was disclosed in the US patent No. 4,818,915. In another US patent No. 5,990,599 there is also disclosed an architecture design of the UV enhancer, which is arranged in an individual bridge supporting structure. However, the UV enhancer in the prior art does not have an ideal performance. Summary of the Invention

[0003] Hereinafter, a brief summary of the present invention is given, so as to provide a basic understanding of some aspects of the present invention. It should be understood that the summary is not an exhaustive summary of the invention. The summary neither intends to determine the critical part or important part of the invention, nor intends to limit the scope of the invention. The object of the summary is only presenting some concepts in a brief form, which is used as a preamble of the detailed description that will be presented later.

[0004] In view of the above defects in the prior art, the present invention provides an improved auxiliary starter for a lighting device. The auxiliary starter has a discharging vessel, a supporter and a feeding device, wherein the discharging vessel gas tightly encloses filling gas and has at least one radiation transmission region, the supporter is arranged in the discharging vessel and is conductively connected to the feeding device which passes through the discharging vessel, wherein the discharging vessel has emitting material for emitting electrons on the surface thereof. Thus, the electron emission of the auxiliary starter is facilitated, and thus the ignition time of the lighting device which utilizes the auxiliary starter to assist starting is shortened .

[0005] Moreover, the present invention provides a lighting device, which comprises an auxiliary starter according to the embodiments of the invention, and the auxiliary starter is used for assisting the starting of the lighting device.

Brief Description of the Drawings

[0006] The present invention may be better understood by referring to the description hereinafter in combination with the drawings, wherein in the drawings, the same or similar reference signs are used to indicate the same or similar components. The same elements or the elements having the same function are designated with the reference signs with corresponding endings. The headers of the reference signs are changed according to different drawings. The drawings are illustrative and have no limitation intention. All the drawings and the detailed description hereinafter are included in the specification and constitute a part of the specification, and are used to further present examples to illustrate the preferred embodiments of the invention and explain the principles and advantages of the invention. Wherein: [0007] Figure 1 shows a schematic diagram of an auxiliary starter for the lighting device according to an embodiment of the invention,

[0008] Figure 2 shows a schematic diagram of the auxiliary starter for the lighting device according to another embodiment of the invention,

[0009] Figure 3 shows a schematic diagram of the auxiliary starter for the lighting device according to yet another embodiment of the invention, and

[0010] Figure 4 shows a schematic diagram of a lighting device having the auxiliary starter for the lighting device according to an embodiment of the invention.

Detailed Description of the Embodiments

[0011] Hereinafter, the embodiments of the present invention will be described in combination with the drawings. In view of clearness and conciseness, not all the features of the practical embodiments are described in the description. However, it should be understood that many decisions specific to the embodiments need to be made during the development of any practical embodiments, so as to achieve the specific objects of the developer, and these decisions may be changed with the variation of the embodiments.

[0012] It should be further pointed out here that in the drawings, only the device structure closely related to the solution of the present invention is illustrated in the drawings, and other details having little relation with the present invention is omitted, so as to avoid making the present invention unclear due to unnecessary details.

[0013] Figure 1 shows a schematic diagram of an auxiliary starter for the lighting device according to an embodiment of the invention .

[0014] The auxiliary starter has a discharging vessel 11, a supporter 13 and a feeding device 15. The discharging vessel 11 gas tightly encloses filling gas 12 and has at least one radiation transmission region. The supporter 13 is arranged in the discharg- ing vessel 11 and is conductively connected to the feeding device 15 which passes through the discharging vessel 11. The supporter 13 has emitting material 14 for emitting electrons on the surface thereof .

[0015] In the context of the present application, the expression "the discharging vessel 11 has at least one radiation transmission region" should be understood as follows: the discharging vessel 11 can partly transmit the radiation. In other words, the discharging vessel 11 can entirely transmit the radiation or can only partly transmit the radiation on a specific site, which can be configured appropriately according to practical requirements. In the present field, the radiation generally refers to the UV radiation, but it is not excluded the other radiation that can assist the ignition of the lighting device. Moreover, the filling gas 12 can generally be argon gas, neon gas or the mixture thereof.

[0016] The shadowed region shown in Figure 1 schematically shows the emitting material 14 on the surface of the supporter 13. The emitting material 14 can be arranged on at least a part of the surface of the supporter 13 equally, unequally, or according to a predefined pattern. In other words, the emitting material can be distributed on the surface of the supporter 13 in arbitrary shape and fashion. The emitting material 14 can cover the surface of the supporter 13 equally and partly, or can entirely cover the surface of the supporter 13, or can also cover the surface of the supporter partly or entirely in an unequal manner. The emitting material 14 can even be distributed on the supporter 13 in a specific pattern according to the requirements of the application.

[0017] The emitting material 14 on the surface of the supporter 13 is suitable for generating electrons. During the operation of the auxiliary starter, the emitting material 14 on the surface of the supporter 13 is advantageous for the generation of the radiation, so that a quicker ignition of the lighting device arranged near the auxiliary starter may be facilitated. Thus, the start time of the lighting device may be shortened. Thus, the start characteristic of the lighting device is improved.

[0018] It is only schematically shown here the geometrical shape of the auxiliary starter (here is elliptical shape) . For those skilled in the art, other geometrical shape can also be applied in the present invention, such as spherical shape, rectangle shape, square shape or even irregular shape. The selection of the specific shape may be determined according to the requirements of the practical application.

[0019] Further, it is to be pointed out that the feeding device 15 is only schematically illustrated here. The feeding device 15 can also have various shapes, such as a rod or slice, etc. The feeding device 15 can be formed by the solid body made of conductive material, or be formed by solid body or hollow body made of non- conductive material which is coated with conductive material. The conductive material may be various metal, alloy thereof or conductive composite material. In other words, the material of the feeding device 15 is selected so that the feeding device 15 can conduct current, and the bonding between the feeding device 15 and the discharging vessel 11 can be maintained secure when the temperature is changed due to the operation of the auxiliary starter. In other words, the selection of the material of the feeding device 15 should further take the material of the discharging vessel 11 in contact with it into consideration. The reason is that a thermal expansion of the discharging vessel 11 and the feeding device 15 in contact with it may be caused during the operation of the auxiliary starter, thus it is required that the thermal coefficients of expansion of the material of both of them is close to each other, so that the bonding between them can remain secure even under the influence of the temperature. In particular, the thermal expansion coefficient of the feeding device 15 coated with the conductive material on its surface or the feeding device 15 made of the conductive material is close to that of the material of the discharging vessel 11 . For example, the discharging vessel 11 is preferably made of the quartz glass. In this case, the conductive material with a thermal expansion coefficient that is close to the thermal expansion coefficient of the quartz glass may be selected, such as molybdenum. The selection of the material of the discharging vessel 11 and the feeding device 15 is performed here only for illustration. The present invention is not limited to the corresponding material as listed, but the material can be selected based on the cost and the processing technology according to the requirements of the application.

[0020] Moreover, the feeding device 15 passes through the discharging vessel 11 and is conductively connected to the supporter 13. The conductive connection can be achieved through welding or may be fixedly connected in a mechanical manner, and thus the conductive connection may be formed. The feeding device 15 is not only used for supplying energy but also used for supporting the supporter 13.

[0021] The supporter 13 is also schematically shown as a rectangular slice. However, the supporter 13 may also have various shapes, such as rod-like, sheet-like, spherical shape or even irregular shape, etc. The supporter 13 can be formed by a solid body made of conductive material as the feeding device 15, or can be formed by coating the solid body or hollow body made of non-conductive material with the conductive material.

[0022] In an alternative embodiment, the emitting material 14 can be arranged on at least a part of the surface of the supporter 13 by doping. The term "doped" herein should be understood as follows: a few other element or compound is doped in a material, so as to improve or change the electrical, magnetic and optical performance of the material. In particular, in the present application, the emitting material 14 is doped into the supporter 13, thereby the capability of emitting election of the supporter 13 is improved, so that the ignition characteristic can be improved. The emitting material 14 may be doped on a part of or the whole surface of the supporter 13 according to the application requirements .

[0023] Alternatively, the emitting material 14 can also be arranged on at least a part of the surface of the supporter 13 by coating. The emitting material 14 can be coated on the surface of the supporter 13 in an arbitrary shape and fashion. For example, the emitting material may be distributed on the surface of the supporter 13 in a specific pattern. [0024] Moreover, no matter the emitting material 14 is arranged by doping or coating, the emitting material 14 is a material that can improve the electron emitting capability and reduce the work function of emission. For example, the emitting material is selected from any one of the following: the elementary substance or compound of the metal element

Y, Ag, Ba, Cd, Hf, La, Tl, Yb, Al, Ce, Eu_¾ Li, Na, Tb, Zn, As, In, Lu, S m, Zr, Ca, Cs, Gd, K, Rb, Sc, Sr. Moreover, it should be understood by those skilled in the art that other metal or compound thereof that can improve the electron emission can be used in the auxiliary starter of the present invention. They are not listed one by one for conciseness.

[0025] Hereinafter, the auxiliary starter for the lighting device according to the embodiment of the invention is illustrated in more detail with the drawings. It should be understood that the present invention is not limited to the described embodiment due to the description in combination with the drawings.

[0026] Figure 2 shows a schematic diagram of the auxiliary starter for the lighting device according to another embodiment of the invention. It is different from the embodiment of the invention shown in Figure lthat in the embodiment shown in Figure 2, the discharging vessel 21 is divided into two segments, i.e., a segment 21a that can transmit the radiation and a segment 21b that cannot transmit the radiation. Of course, those skilled in the art can modify the division according to specific application requirements (divide into more segments), i.e., according to the application requirements, it may be distributed according to the specific arrangement patterns of the radiation transmission regions and radiation non-transmission regions.

[0027] In a variation, the inner surface of the discharging vessel 21 may be partly coated with reflecting layer, so that the electron emitted by the emitting material 24 on the surface of the supporter 23 is emitted directionally to the lighting device arranged near the auxiliary starter through the reflection of the electron by the reflecting layer, so that the starting of the lighting device is further facilitated. Thus, the starting time of the lighting device is further shortened. Due to the reason of clearness, it is not shown here. The variation is also suitable for the embodiments mentioned in the context of the present application. Figure 3 shows a schematic diagram of the auxiliary starter for the lighting device according to yet another embodiment of the invention. It is different from the embodiment of the invention shown in Figure 1 that the discharging vessel 31 shown in Figure 3 is divided into a bulb part 31a and an extrusion part 31b. The supporter 33 and the feeding device 35 are conductively connected with each other within the extrusion part 31b.

[0028] In the embodiment, the extrusion part 31b makes the supporter be fixed in the discharging vessel 31 more securely, so that the stability of the supporter 33 is further improved. The supporter 33 and the feeding device 35 may conductively contact each other via the extrusion part 31b. In other words, the connection of the supporter 33 and the feeding device 35 by means of adhesive may be omitted, instead they are pressed together by means of the extrusion part 31b.

[0029] Similar to the auxiliary starter shown in Figure 1, the shadowed region shown in Figure 3 only schematically illustrates the emitting material 34 on the surface of the supporter 33. The emitting material 34 can also be distributed on the surface of the supporter in an arbitrary shape and fashion, such as being distributed on the surface of the supporter 33 in a specific pattern. During the operation of the auxiliary starter, the electron generated by the illuminating material 34 on the surface of the supporter will facilitate the lighting device near the auxiliary starter to be ignited more quickly. Thus the starting time of the lighting device may be shortened. Thus, the starting characteristic of the lighting device may be improved.

[0030] It should also be pointed out that only the geometric shape of the auxiliary starter is schematically shown here (which is approximately the combination of the cylinder and rectangular herein) . However, to those skilled in the art, other geometric shape can also be applied in the invention, for example, the spherical shape, rectangular shape, square shape or even irregular shape with the extrusion are also possible. The selection of the specific shape may be determined according to the requirements of the practical application.

[0031] Further, the feeding device 35 may also have various shapes, such as rod-like, slice-like, etc. The feeding device 35 may also be formed by the solid body made of conductive material, or may be formed by coating the solid body or hollow body made of non-conductive material with the conductive material. The conductive material may be various metal, alloy thereof or conductive composite material. Similarly, the supporter 33 is only schematically shown as a rectangular slice herein. However, the supporter 33 may also have various shapes, such as rod-like, sheet-like, spherical shape or even irregular shape etc. The supporter 33 can be formed by the solid body made of conductive material as the feeding device 35, or may be formed by coating the solid body or hollow body made of non-conductive material with the conductive material .

[0032] Since in the embodiment, not only the feeding device 35 but also the supporter 33 are in contact with the extrusion part 31b of the discharging vessel 31, when selecting the material of which the feeding device 35 and the supporter 33 are formed, the material of the discharging vessel 31 in contact with them should also be taken into consideration, so as to ensure that the bonding between these three parts can remain secure even under the influence of the temperature. In particular, the material forming the feeding device 35 and the supporter 33 is similar to the material of the discharging vessel 31 in terms of the thermal expansion coefficient. For example, the discharging vessel 31 is preferably made of the quartz glass. In this case, the conductive material such as Mo that has a thermal expansion coefficient similar to that of the quartz glass may be selected as the material of the feeding device 35 and the supporter 33. Moreover, the materials of the supporter 33 and the feeding device 35 may be the same or different. It is only illustratively shown the material selection of the discharging vessel 31, the supporter 33 and the feeding device 35. The present invention is not limited to the corresponding material as listed, but the material can be selected based on the general consideration of the cost and fabricating process according to the application requirements.

[0033] In a variation, the supporter 33 and the feeding device 35 may also be conductively connected through welding.

[0034] Other components that are not described here in detail, such as the filling gas 32, the emitting material 34, the feeding device 35, are similar to those in the embodiments described according to Figure 1 and Figure 2. Thus, they are not described again here.

[0035] In an alternative embodiment, the supporter 33 may be formed with the feeding device 35 in a one-part manner (not shown) . This is also applicable to the embodiments shown in Figure 1 and 2.

[0036] Similar to the auxiliary starter described in combination with Figure 1, the emitting material 34 is arranged on the surface of the supporter 33 by doping.

[0037] Similar to the auxiliary starter described in combination with Figure 1, the emitting material 34 is arranged on the surface of the supporter 33 by coating. This is also applicable to the embodiments shown in Figure 1 and 2. Additionally or alternatively to the above embodiments, the filling pressure of the start auxiliary gas filled in the discharging vessel 11, 21 and 31 is between 5 mbar to 500 mbar, preferably between 10 mbar to 60 mbar.

[0038] Additionally or alternatively to the above embodiments, the emitting material, in the case of using carbonate as the precursor, may include the oxide of at least one of the following metal: barium, strontium, calcium and zirconium.

[0039] Additionally or alternatively to the above embodiments, the emitting material may also include barium yttrium tungstate (BYT) , barium calcium tungstate (BCT) and barium strontium yittriate (BSY2) .

[0040] Additionally or alternatively to the above embodiments, the BYT, BCT and BSY2 may used as the emitting material separately or in combination.

[0041] In the following table, the parameter comparison between the auxiliary starter according to the embodiment of the invention and two auxiliary starters of the prior art (Starter No. 1 and Starter No. 2) is illustrated through the testing data.

Table 1

As can be seen from the above table, in the case that the intensity of the radiation emitted by the auxiliary starter according to the embodiment of the invention and the intensity of the radiation emitted by the auxiliary starters No. 1 and No. 2 are approximately equal to each other, the ignition voltage for igniting the lighting device by employing the auxiliary starter according to the embodiment of the invention is much smaller than the ignition voltage for igniting the lighting device by employing the auxiliary starters No. 1 and No. 2, and is smaller than 700V. This is beneficial for the starting of the lighting device, shortening the start time and decreasing the starting voltage. Further, the ignition efficiency may be improved, and the device cost may be reduced.

[0042] Figure 4 shows a schematic diagram of a lighting device having the auxiliary starter for the lighting device according to an embodiment of the invention. The lighting device comprises the auxiliary starter 40 according to the embodiment of the invention. The lighting device 40 comprises an outer bulb 46, a burner 43 arranged in the outer bulb, a getter device 44, and conductive holders 41, 42 and 45 for conducting current and fixing, wherein the auxiliary starter 40 is arranged near the burner 43 for starting the lighting device 4. As shown, the auxiliary starter 40 may employ the auxiliary starter described in any aforementioned embodiments. Meanwhile, the lighting device having such auxiliary starter is illustrated by using a metal halide lamp with ceramic burner as an example. The lighting device may also be a metal halide lamp with quartz glass burner.

[0043] Finally, it should be noted that the term "include", "comprise" or any other variations means a non-exclusive inclusion, so that the process, method, article or device that includes a series of elements includes not only these elements but also other elements that are not explicitly listed, or further includes inherent elements of the process, method, article or device. Moreover, when there is no further limitation, the element defined by the wording "include (s) a ..." does not exclude the case that in the process, method, article or device that includes the element there are other same elements.

[0044] The embodiments of the invention are described in detail in combination with drawings. However, it should be understood that the embodiments described above are only used for illustrating the invention, and do not constitute a limitation of the invention. Various modifications and variations may be made to the above embodiments by those skilled in the art, without departing from the essential and scope of the present invention. Therefore, the scope of the present invention is only defined by the appended claims and the equivalent meanings thereof.

Claims

Patent claims

1. An auxiliary starter for a lighting device, comprising a discharging vessel (11, 21, 31), a supporter (13, 23, 33) and a feeding device (15, 25, 35) , wherein the discharging vessel (11, 21, 31) gas tightly encloses filling gas (12, 22, 32) and has at least one radiation transmission region, the supporter (13, 23, 33) is arranged in the discharging vessel (11, 21, 31) and is con- ductively connected to the feeding device (15, 25, 35) which passes gastightly through the discharging vessel (11, 21, 31) , characterized in that the supporter (13, 23, 33) has emitting material (14, 24, 34) for emitting electrons on the surface thereof.

2. The auxiliary starter according to claim 1, characterized in that the emitting material (14, 24, 34) is arranged on at least a part of the surface of the supporter (13, 23, 33) by coating.

3. The auxiliary starter according to claim 1, characterized in that the emitting material (14, 24, 34) is arranged on at least a part of the surface of the supporter (13, 23, 33) by doping.

4. The auxiliary starter according to any one of the preceding claims, characterized in that the emitting material (14, 24, 34) is arranged on at least a part of the surface of the supporter (13, 23, 33) equally, unequally, or according to a predefined pattern .

5. The auxiliary starter according to any one of the preceding claims, characterized in that the cold filling pressure of the filling gas enclosed in the discharging vessel (11, 21, 31) is between 5 mbar to 500 mbar, preferably between 10 mbar to 60 mbar.

6. The auxiliary starter according to any one of the preceding claims, characterized in that the filling gas (12, 22, 32) com- prises argon gas, neon gas or the mixture thereof.

7. The auxiliary starter according to any one of the preceding claims, characterized in that the emitting material (14, 24, 34) is a material that can improve the electron emitting capability and reduce the work function of emission.

8. The auxiliary starter according to any one of the preceding claims, characterized in that the emitting material (14, 24, 34), in the case of using carbonate as the precursor, includes the oxide of at least one of the following metal: barium, strontium, calcium and zirconium.

9. The auxiliary starter according to any one of claims 1 to 7, characterized in that BYT, BCT and BSY2 are used as the emitting material (14, 24, 34) separately or in combination.

10. The auxiliary starter according to any one of claims 1 to 7, characterized in that the emitting material is selected from any one of the following: the elementary substance or a compound of the metal element Y, Ag, Ba, Cd, Hf, La, Tl, Yb, Al, Ce, Eu, Li, Na, Tb, Zn, As, In, Lu, Sm, Zr, Ca, Cs, Gd, K, Rb, Sc, Sr.

11. The auxiliary starter according to any one of the preceding claims, characterized in that the inner surface of the discharging vessel (11, 21, 31) is partly coated with reflecting layer, so that the electron emitted by the emitting material (14, 24, 34) on the surface of the supporter (13, 23, 33) is emitted directionally through the reflection by the reflecting layer.

12. The auxiliary starter according to any one of the preceding claims, characterized in that the supporter (13, 23, 33) is formed with the feeding device (15, 25, 35) in a one-part manner.

13. The auxiliary starter according to any one of the preceding claims, characterized in that the material of the supporter (13, 23, 33) and/or of the feeding device (15, 25, 35) is selected so that the supporter (13, 23, 33) and the feeding device (15, 25, 35) conducts current, and the gastight passing of the feeding de- vice (15, 25, 35) through the discharging vessel (11, 21, 31) can be maintained securely gastight when the temperature is changed due to the operation of the auxiliary starter.

14. A lighting device, comprising the auxiliary starter according to any one of claims 1 to 13, wherein the auxiliary starter is used for starting the lighting device.

15. The lighting device according to claim 14, characterized in that the lighting device is a metal halide lamp with quartz glass burner or a metal halide lamp with ceramic burner.