WO2014023553A1

WO2014023553A1 - Lamp tube, process for manufacturing the lamp tube, and illumination apparatus comprising the lamp tube

Info

Publication number: WO2014023553A1
Application number: PCT/EP2013/065297
Authority: WO
Inventors: Yusheng MING; Chengcheng FENG; Xiaomian Chen; Peng Chen; Hao Li
Original assignee: Osram Gmbh
Priority date: 2012-08-07
Filing date: 2013-07-19
Publication date: 2014-02-13
Also published as: CN103574492A

Abstract

The present invention relates to a lamp tube (10), comprising a tube body (1) made of glass, characterized in that, the tube body (1) comprises a first portion (2) and a second portion (3), wherein at least one of an inner circumferential wall (A1) and an outer circumferential wall (A2) of the second portion (3) is provided with a structure for reducing transparency. In addition, the present invention further relates to a process for manufacturing the lamp tube, and an illumination apparatus comprising the lamp tube.

Description

Lamp Tube, Process for Manufacturing the Lamp Tube, and

Illumination Apparatus Comprising the Lamp Tube

Technical Field

The present invention relates to a lamp tube, a process for manufacturing the lamp tube, and an illumination apparatus comprising the lamp tube. Background Art

In today's illumination apparatuses, the illumination appara^¬ tuses with a glass lamp tube as the housing are widely used. In order to improve the efficiency of the illumination appa^¬ ratuses and save power, an LED light source can be installed in the glass lamp tube to repl3.CG _/ cL S a tubular retrofit lamp, the conventional fluorescent lamp. However, the circuit board carrying the LED light source, the driver, and other electronic devices such as wires also need to be placed in the tubular retrofit lamp. Thus, the user can see these in- ternal electronic devices directly through the glass tube, which greatly affects the appearance of the retrofit lamp. Therefore, it is necessary to provide a beautiful and practi^¬ cal glass lamp tube as the housing of a retrofit lamp.

Summary of the invention Thus, it is an object of the present invention to provide a lamp tube, which is easy to manufacture, has good appearance, and can replace the conventional glass tubes for use in vari^¬ ous illumination occasions. The lamp tube according to the present invention comprises a tube body made of glass, characterized in that, the tube body comprises a first portion and a second portion, wherein at least one of an inner circumferential wall and an outer circumferential wall of the second portion is provided with a structure for reducing transparency. In order to replace the conventional totally transparent glass tube, the circumferen^¬ tial wall of the tube body constituting the lamp tube is par^¬ ticularly processed, viz. a particular optical structure is provided in part of the region on the inner circumferential wall and/or the outer circumferential wall of the tube body, and the transparency of the region with the optical structure is lower than that of the other region. Part of the region of such lamp tube is invisible for the user, or at least cannot be seen clearly.

According to a preferred design solution of the present invention, the structure for reducing transparency is an opti^¬ cal layer which is individually coated on at least one circumferential wall of the second portion. Preferably, the optical layer is a reflective layer. The optical layer can be designed as a reflective layer coated on the inner circumfer^¬ ential wall and/or the outer circumferential wall of the tube body. The non-transparent reflective layer not only can serve as a shading layer shading some space in the tube body, but also can, in the case where there is a light source within the tube body, reflect the light from the light source through the transparent first portion towards a predetermined direction, so as to improve the light extracting rate of the first portion. According to another preferred embodiment of the present in^¬ vention, the reflective layer contains one of the following materials: silver and aluminum. Since silver or aluminum has good reflective properties, the reflective layer containing silver or aluminum can achieve the effect of mirror- reflection .

According to a preferred design solution of the present in- vention, the structure for reducing transparency is a diffuse structure formed by etching the second portion. By means of the diffuse structure formed by etching, the circumferential wall of the second portion becomes unsmooth, which makes it impossible for the user to see the inside of the tube body directly or clearly.

According to a preferred design solution of the present invention, the second portion extends in a longitudinal direc^¬ tion of the tube body, and extends in a circumferential di^¬ rection of the tube body by a predetermined angle. As the light emergent surface of a lamp tube is usually its longitu^¬ dinal side surface, the transparent first portion and the second portion which at least cannot be totally transparent are designed to have a strip-like semi-tubular section. The proportion of the first portion and the proportion of the second portion in the circumferential direction can be ad^¬ justed according to practical needs, for example, in the circumferential direction, the first portion either can be equal to the second portion, or can be larger or smaller than the second portion. According to a preferred design solution of the present in^¬ vention, the predetermined angle is 180°. The upper half por^¬ tion of the so-formed lamp tube in an axial direction is, for example, the second portion having a reflective surface or a diffuse structure, and the lower half portion is the trans- parent first portion. According to a preferred design solution of the present invention, the inner circumferential wall is provided with a structure for reducing transparency. Corresponding to the de^¬ sign solution in which the structure for reducing transpar- ency is provided on the outer circumferential wall of the tube body, the optical surface which is preferably a reflec^¬ tive surface can also be coated on the inner wall of the lamp tube, to serve as a shading structure on the inner circumfer^¬ ential wall of the second portion; or etching is performed on the inner circumferential wall of the second portion to form a diffuse structure.

According to a preferred design solution of the present invention, the lamp tube further comprises a partition board formed on the inner circumferential wall, the partition board partitioning the tube body into the first portion and the second portion. When it is necessary to dispose the diffuse structure or the optical layer within the tube body, an addi^¬ tional partition board is preferably disposed within the tube body, such that the first portion and the second portion are separated from each other by the partition board, which simplifies the processing on the second portion.

According to a preferred design solution of the present invention, the partition board is made in one piece with the tube body. The partition board which is made of the same ma- terial as the tube body serves to separate the first portion from the second portion, serves as a supporting board for carrying, for example, a light engine, and can also increase the thermal conductive area of the tube body.

According to another preferred design solution of the present invention, a rubber strip is arranged between the partition board and the tube body. The partition board can also be an element additionally provided in the tube body, and in order to avoid friction or scratch between the partition board and the tube body made of glass, a rubber strip is preferably provided between them as a buffer. The present invention also relates to an illumination appara^¬ tus comprising a light engine and a driver, characterized by further comprising the above mentioned lamp tube, wherein the light engine and the driver are arranged in the lamp tube. Such illumination apparatus has good appearance, and the user cannot directly or clearly see the driver in the lamp tube.

According to a preferred design solution of the present invention, a light emergent surface of the light engine faces the first portion, and the driver faces the second portion. The light engine carrying the light source is arranged to face the transparent first portion for sufficient and effi^¬ cient illumination; and the driver which does not need to be seen is preferably arranged on a side close to the second portion in the lamp tube, in order to improve the visual ef^¬ fects of the illumination apparatus. The present invention further relates to a process for manu^¬ facturing the above mentioned lamp tube, characterized by comprising the steps of: a) providing a totally transparent tube body made of glass; b) providing a retaining element re^¬ tained on the tube body and partitioning, in a circumferen- tial direction, the tube body into two portions; and c) ena^¬ bling one of the two portions to serve as a totally transpar^¬ ent first portion, and processing at least one of an inner circumferential wall and an outer circumferential wall of the other portion, to form a structure for reducing transparency, as a second portion. The proportion of the first portion and the proportion of the second portion in the circumferential direction are selected in accordance with the location of the electronic devices which need to be installed in the lamp tube, thus forming the second portion having relatively low transparency, for shading some of the devices which need to be installed within the lamp tube.

According to a preferred design solution of the present invention, in the step b) , the retaining element is a pair of clamping arms retained on the outer circumferential wall, and in the step c) , a reflective layer is coated on the outer circumferential wall to form the structure for reducing transparency. For example, it is feasible to process the re^¬ gion which does not need to be transparent from the outside of the lamp tube, and to form the second portion whose trans^¬ parency is reduced, by directly applying a reflective layer. According to a preferred design solution of the present in^¬ vention, in the step b) , the retaining element is a partition board retained on the inner circumferential wall, and in the step c) , the inner circumferential wall is etched to form the structure for reducing transparency. The tube body is defined as the first portion and the second portion through the par^¬ tition board, which allows simple etching process to the pre^¬ determined region defined by the partition board to form the second portion.

According to a preferred design solution of the present in- vention, in the step b) , the partition board and the tube body are made in one piece. For example, the methods such as hot-melt method can be used to connect the glass partition board and the tube body as one piece.

According to another preferred design solution of the present invention, in the step b) , a rubber strip is clamped between the partition board and the tube body.

It shall be understood that both the above general descrip^¬ tion and the following detailed description are for illustrative and explanative purposes in order to provide further de^¬ scription on the claimed present invention.

Brief Description of the Drawings

The drawings constitute a portion of the Description for fur^¬ ther understanding of the present invention. These drawings illustrate the embodiments of the present invention and ex^¬ plain the principle of the present invention together with the Description. In the drawings, the same part is repre^¬ sented by the same reference sign. In the drawings,

Fig. 1 shows the first embodiment of the illumination appara^¬ tus according to the present invention;

Fig. 2 shows the first embodiment of the process for manufac^¬ turing the lamp tube of the illumination apparatus in Fig. 1 ;

Fig. 3 shows the second embodiment of the illumination appa^¬ ratus according to the present invention; and

Fig. 4 shows the second embodiment of the process for manu^¬ facturing the lamp tube of the illumination apparatus in Fig. 3.

Detailed Description of the Embodiments

In the following detailed Description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. In this regard, direc^¬ tional terminology, such as "top", "bottom", "inner", "outer" etc., is used with reference to the orientation of the Fig^¬ ure (s) being described. Because components of embodiments can be positioned in a number of different orientations, the di^¬ rectional terminology is used for purposes of illustration and is in no way limiting. It is to be understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present invention. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims.

It is to be understood that the features of the various exem^¬ plary embodiments described herein may be combined with each other, unless specifically noted otherwise.

In order to replace the conventional totally transparent glass tube, the circumferential wall of the tube body 1 con^¬ stituting the lamp tube 10 is particularly processed, viz. a particular optical structure is provided in part of the re- gion on the inner circumferential wall Al and/or the outer circumferential wall A2 of the tube body 1, and the transpar^¬ ency of the region with the optical structure is lower than that of the other region. Part of the region of such lamp tube 10 is invisible for the user, or at least cannot be seen clearly.

Fig. 1 shows the first embodiment of the illumination appara^¬ tus according to the present invention. As can be seen from the sectional view shown in Fig. 1, the tube body 1 of the illumination apparatus 100 with the lamp tube 10 as its hous- ing is divided, in the circumferential direction, into two equal portions. The upper half portion of the tube body 1 is the second portion 3, and the first portion 2 facing the sec^¬ ond portion 3 is the lower half portion of the tube body 1. The second portion 3 has a structure for reducing transparency, and in the present embodiment, the structure for reduc- ing transparency is an optical layer coated on the outer circumferential wall A2 of the second portion 3. The optical layer is preferably a reflective layer 4, which has double functions of blocking light on one side and reflecting light on the other side. The light engine 21 and the driver 22 of the illumination apparatus 20 can be disposed in the lamp tube 10, as shown in Fig. 1, viz. one side of the light en^¬ gine 21 carrying the light source faces the transparent first portion 2, the driver 22 is installed, in the vertical direc^¬ tion, above the light engine 21, and the reflective layer 4 on the outer circumferential wall A2 of the second portion 3 and the light engine 21 define the driver 22 in a region in^¬ visible from the outside of the lamp tube 10, which thereby prevents the user from seeing the driver 22 from the outside, and improves the aesthetic property of the illumination appa- ratus 20.

The reflective layer 4 can be a coating containing silver or aluminum. Such reflective layer 4 not only has superior light blocking effect, but also can further reflect the received light in a predetermined direction, for example, reflecting the light in the lamp tube 10 towards the transparent first portion 2, thereby improving the light intensity of the light emerging from the first portion 2.

In addition, in accordance with the sizes of the light engine 21 and the driver 22, the proportions of the first portion 2 and the second portion 3, which extend in the axial direction of the lamp tube 10, in the circumferential direction can be adjusted. When the light engine 21 has a small area in cross section, the circumferential area occupied by the reflective layer 4 for shading the light engine 21 can be correspond^¬ ingly reduced. That is, the angle by which the second portion 3 extends in the circumferential direction may be smaller than 180°, for example, only 120°. When the light engine 21 has a large area in cross section, the area of the outer circumferential wall occupied by the reflective layer 4 for shading the light engine 21 can be correspondingly increased. That is, the angle by which the second portion 3 extends in the circumferential direction may be greater than 180°, for example, can be 240°.

Fig. 2 shows the first embodiment of the process for manufac^¬ turing the lamp tube of the illumination apparatus in Fig. 1. Firstly, the totally transparent tube body 1 made of glass is provided. By means of a pair of clamping arms 7 which clamp the tube body 1 from the outside, the tube body 1 to be proc^¬ essed is located at a predetermined position. The clamping arms 7 can also divide, in the circumferential direction, the tube body 1 into two portions. Subsequently, at least one circumferential wall (the outer circumferential wall A2 in the present embodiment) of the inner circumferential wall Al and the outer circumferential wall A2 of one of the two por^¬ tions is processed to form a structure for reducing transpar^¬ ency as the second portion 3 which can be used for shading the devices placed in the tube body 1; and the other portion which is not processed serves as the totally transparent first portion 2. In the present embodiment, the structure for reducing transparency is the reflective layer 4 which is in^¬ dividually sprayed onto the outer circumferential wall A2 of the lower half portion of the tube body 1.

The so-formed second portion 3 has an optical layer extending in the axial direction of the lamp tube 10. The first portion 2 adjacent to the second portion 3 in the circumferential di^¬ rection also extends in the axial direction of the lamp tube 10, and the first portion maintains the superior transmissiv- ity of the tube body 1. Thus, the lamp tube 10 comprises the first portion 2 having relatively high transparency and the second portion 3 having relatively low transparency, which is opaque here.

In an embodiment not shown, part of the outer circumferential wall of the tube body can be etched to form the second por- tion having a diffuse structure. The outer circumferential wall of the so-formed second portion is, for example, a frosted surface or other similar optical surface, and the user cannot see, from one side of the optical surface, an ob^¬ ject on the other side. That is, the user cannot clearly see, from the outside of the second portion of the lamp tube, the electronic devices installed in the lamp tube.

Fig. 3 shows the second embodiment of the illumination appa^¬ ratus according to the present invention. The lamp tube 10 of the illumination apparatus 100 in the present embodiment com- prises a strip-like partition board 5 retained within the tube body 1. The partition board 5 can be made in one piece with the tube body 1, such that the thermal contact area of the tube body 1 can be increased, which makes it easy to carry the electronic assemblies installed thereon, and to dissipate heat. Another important function of the partition board 5 is to partition, in the extending direction of the lamp tube 10, the tube body 1 into the upper first portion 2 and the lower second portion 3. The inner circumferential wall Al of the second portion 3 at least comprises a struc- ture for reducing transparency. Such structure for reducing transparency can be a diffuse structure 4' formed by process^¬ ing the inner circumferential wall Al of the second portion 3. In an embodiment not shown, such structure for reducing transparency can be an optical layer coated on the inner circumferential wall Al .

In the case where the partition board 5 is directly used as a supporting board, the light engine 21 of the illumination ap^¬ paratus 20 can be preferably arranged on the top surface of the partition board 5, which allows the light from the light source on the light engine 21 to directly go through the up^¬ per first portion 2 of the lamp tube 10. Meanwhile, the driver 22 of the illumination apparatus 20 which is not de^¬ sired to be seen is arranged on the bottom surface of the partition board 5, and thereby, the driver 22 is accommodated in a non-totally transparent space defined by the partition board 5 and the lower second portion 3 of the lamp tube 10. The user cannot directly or clearly see, from the outside of the lamp tube 10, the driver 22 surrounded by the second por^¬ tion 3.

Fig. 4 shows the second embodiment of the process for manu^¬ facturing the lamp tube of the illumination apparatus in Fig. 3. The totally transparent tube body 1 made of glass is firstly provided, and then a retaining element for partition^¬ ing the tube body 1 into two portions is additionally pro^¬ vided in the tube body 1. The retaining element is shown as the partition board 5 in Fig. 3. The retaining element can be made in piece with the tube body 1, to thereby increase the thermal contact area of the tube body 1, which makes it easy to carry the electronic assemblies installed thereon, and dissipate heat. The partition board 5 can also be fixed within the tube body 1 by means of mechanical connection, as shown in the figure, or rather, two side end surfaces of the partition board 5 are pressed against the inner circumferen^¬ tial wall Al of the tube body 1. In this case, in order to reduce the abrasion between the partition board 5 and the inner circumferential wall Al, the rubber strip 6 which serves as a buffer can be particularly arranged between the partition board 5 and the inner circumferential wall Al . Finally, the inner circumferential wall of a part of the tube body 10 partitioned off by the partition board 5 can be proc^¬ essed to form a structure for reducing the transparency of the part. Preferably, through the etching process, a diffuse structure 4' is formed directly on the inner circumferential wall Al of the upper tube body 1 defined by the partition board 5. By the partition board 5 partitioning the inner circumferential wall Al, the selected region on the inner circumferential wall Al can be etched simply and precisely, which greatly simplifies the manufacture process of the lamp tube 10.

Also, a reflective layer may be used to replace the diffuse structure, and then, a reflective layer or similar optical layers can be directly coated on the partial inner circumfer^¬ ential wall defined by the partition board, so as to form the second portion invisible from the outside.

In the scope of the present invention, it is feasible to pro^¬ vide an optical layer on only the inner circumferential wall or only the outer circumferential wall of the second portion, or to process only the inner circumferential wall or only the outer circumferential wall of the second portion into a dif^¬ fuse structure; it is also feasible to provide an optical layer on both the inner circumferential wall and the outer circumferential wall of the second portion, or to process both the inner circumferential wall and the outer circumfer- ential wall of the second portion into a diffuse structure. Further, the second portion may be designed to have an opti- cal layer on one side and a diffuse structure on the other side .

The above is merely preferred embodiments of the present in^¬ vention but not to limit the present invention. For the per- son skilled in the art, the present invention may have vari^¬ ous alterations and changes. Any alterations, equivalent sub^¬ stitutions, improvements, within the spirit and principle of the present invention, should be covered in the protection scope of the present invention.

, _n

15

List of reference signs

1 tube body

2 first portion

3 second portion

4 reflective layer

4' diffuse structure

5 partition board

6 rubber strip

7 clamping arm

10 lamp tube

20 illumination apparatus

21 light engine

22 driver

Al inner circumferential wall A2 outer circumferential wall

Claims

1. 1. A lamp tube (10), comprising a tube body (1) made of glass, characterized in that, the tube body (1) comprises a first portion (2) and a second portion (3), wherein at least one of an inner circumferential wall (Al) and an outer circumferential wall (A2) of the second portion (3) is pro^¬ vided with a structure for reducing transparency.

2. The lamp tube (10) according to Claim 1, characterized in that, the structure for reducing transparency is an optical layer which is individually coated on at least one circumfer^¬ ential wall of the second portion (3) .

3. The lamp tube (10) according to Claim 2, characterized in that, the optical layer is a reflective layer (4) .

4. The lamp tube (10) according to Claim 3, characterized in that, the reflective layer (4) contains one of the following materials: silver and aluminum.

5. The lamp tube (10) according to Claim 1, characterized in that, the structure for reducing transparency is a diffuse structure (4') formed by etching the second portion (3) .

6. The lamp tube (10) according to any of Claims 1-5, charac^¬ terized in that, the second portion (3) extends in a longitu^¬ dinal direction of the tube body (1), and extends in a circumferential direction of the tube body (1) by a predeter- mined angle.

7. The lamp tube (10) according to Claim 6, characterized in that, the predetermined angle is 180°.

8. The lamp tube (10) according to any of Claims 1-5, charac^¬ terized in that, the inner circumferential wall (Al) is pro^¬ vided with a structure for reducing transparency.

9. The lamp tube (10) according to Claim 8, characterized by further comprising a partition board (5) formed on the inner circumferential wall (Al), the partition board (5) partition^¬ ing the tube body (1) into the first portion (2) and the sec^¬ ond portion (3) .

10. The lamp tube (10) according to Claim 9, characterized in that, the partition board (5) is made in one piece with the tube body (1) .

11. The lamp tube (10) according to Claim 9, characterized in that, a rubber strip (6) is arranged between the partition board (5) and the tube body (1) .

12. A tubular illumination apparatus (20), comprising a light engine (21) and a driver (22), characterized by further comprising a lamp tube (10) according to any of Claims 1-11, wherein the light engine (21) and the driver (22) are arranged in the lamp tube (10) .

13. The illumination apparatus (20) according to Claim 12, characterized in that, a light emergent surface of the light engine (21) faces the first portion (2), and the driver (22) faces the second portion (3) .

14. A process for manufacturing a lamp tube (10) according to any of Claims 1-11, characterized by comprising the steps of: a) providing a totally transparent tube body (1) made of glass; b) providing a retaining element retained on the tube body (1) and partitioning, in a circumferential direction, the tube body (1) into two portions; and c) enabling one of the two portions to serve as a totally transparent first por^¬ tion (2), and processing at least one of an inner circumferential wall (Al) and an outer circumferential wall (A2) of the other portion, to form a structure for reducing transparency, as a second portion (3) .

15. The process according to Claim 14, characterized in that, in the step b) , the retaining element is a pair of clamping arms (7) retained on the outer circumferential wall (A2), and in the step c) , a reflective layer (4) is coated on the outer circumferential wall (A2) to form the structure for reducing transparency.

16. The process according to Claim 14, characterized in that, in the step b) , the retaining element is a partition board (5) retained on the inner circumferential wall (Al), and in the step c) , the inner circumferential wall (Al) is etched to form the structure for reducing transparency.

17. The process according to Claim 16, characterized in that, in the step b) , the partition board (5) and the tube body (1) are made in one piece.

18. The process according to Claim 16, characterized in that, in the step b) , a rubber strip (6) is clamped between the partition board (5) and the tube body (1) .