WO2014056999A1

WO2014056999A1 - Led retrofit lamp

Info

Publication number: WO2014056999A1
Application number: PCT/EP2013/071087
Authority: WO
Inventors: Xueqin LIN; YingJun CHENG; Yang Hu; Xinkai ZHAO
Original assignee: Osram Gmbh
Priority date: 2012-10-12
Filing date: 2013-10-09
Publication date: 2014-04-17
Also published as: CN103727421A

Abstract

The present invention relates to an LED retrofit lamp (100), comprising: a bearing structure (1); a circuit board (2) disposed at one side of the bearing structure (1); and a lens (3), wherein, the circuit board (2) is erected at the bearing structure (1), and the circuit board (2) comprises a first side (21) and a second side (22) provided with at least one LED chip, respectively, wherein, the lens (3) comprises a first lens part (31) and a second lens part (32) mounted at the first side (21) and the second side (22), wherein, the light from the LED chip passes through the first lens part (31) and the second lens part (32) respectively and then is exited.

Description

LED Retrofit Lamp Technical Field

The present invention relates to an LED retrofit lamp.

Background Art

LED illumination has advantages of high light emitting efficiency, long service life and being green and environmentally friendly. Thus, there are more and more illuminating devices in the market using the LED as a light source. An LED retro^¬ fit lamp is mainly used to replace light sources in tradi^¬ tional illuminating devices, for example, traditional incan^¬ descent lamp or lamp tube. Therefore, the LED retrofit lamp needs to be mounted in a lamp holder of the traditional illu^¬ minating devices, thus the LED retrofit lamp needs to have a shape of the traditional incandescent lamp or lamp tube. In addition, for example, the traditional incandescent lamp can realize so-called omnidirectional illumination, while the LED retrofit lamp for replacing the incandescent lamp should also be able to achieve omnidirectional illumination. Therefore, there appear many different kinds of LED omnidirectional il^¬ luminating devices in the prior art. Solutions in the prior art mainly dispose multiple LED chips in different directions to realize omnidirectional illumination. However, this ar^¬ rangement manner has a main defect of placing high require^¬ ments on a driver and a driving voltage as multiple LED chips are used.

Summary of the Invention

To solve the above technical problem, the present invention provides an LED retrofit lamp. The LED retrofit lamp accord^¬ ing to the present invention can realize omnidirectional il- lumination and also save more energy, has a simple structure and can be easily assembled.

The object of the present invention is achieved through an LED retrofit lamp, that is, the LED retrofit lamp comprises: a bearing structure; a circuit board arranged at one side of the bearing structure; and a lens, wherein, the circuit board is erected at the bearing structure, and comprises a first side and a second side provided with at least one LED chip, respectively, wherein, the lens comprises a first lens part and a second lens part mounted at the first side and the sec^¬ ond side, and wherein, the light from the LED chip passes through the first lens part and the second lens part respec^¬ tively and then is exited. In the design solution of the pre^¬ sent invention, as the circuit board is erected at the bear- ing structure, the two sides of the circuit board respec^¬ tively face two different directions, LED chips are respec^¬ tively arranged at two sides, and thus the LED chips on dif^¬ ferent sides also emit light in different directions. In ad^¬ dition, each side of the circuit board is provided with a lens part, and such lens parts can conduct second optical treatment on the light emitted from each side of the LED chip, so that the light emitted from each side of the LED chip can cover at least one semispherical area and then the LED retrofit lamp according to the present invention can re- alize omnidirectional illumination.

As put forward in the present invention, the first lens part and the second lens part sandwich the circuit board therebe^¬ tween. In the design solution of the present invention, the circuit board can serve as the carrier of the lens and sup- port the lens, thus it is unnecessary to provide a separate support structure for the lens, which reduces the number of the parts of the LED retrofit lamp to a certain extent and lowers cost.

As put forward in a preferable design solution of the present invention, the first lens part and the second lens part are designed so that the light from the LED chip passes through the first lens part and the second lens part and then covers the area at two sides of the circuit board to achieve omnidi^¬ rectional illumination. As the LED chips are disposed at two opposites sides of the circuit board, the lens parts disposed at two sides of the circuit board are also correspondingly in charge of the semispherical areas corresponding to the two sides of the circuit board, and then conduct second optical treatment on the light emitted from the LED chips to realize omnidirectional illumination. The omnidirectional illumina^¬ tion can be realized through a simple optical structure, and thus the solution of arranging multiple LED chips in the il^¬ luminating device is avoided, which to a large extent lowers the requirements on the driver and the driving voltage, and the number of the parts of the LED retrofit lamp is greatly lowered, which to a certain extent lowers the cost. Preferably, the first lens part and the second lens part are mirror symmetric with respect to the circuit board, and then the light emitted from the two lens parts is also symmetric in the two corresponding semispherical areas. However, in other design solutions of the present invention, the two lens parts may not be mirror symmetric, either, thereby obtaining desired illumination effect. In this situation, the light emitted from the two lens parts is not symmetric in respec^¬ tive semispherical areas.

Preferably, the first lens part and the second lens part re- spectively comprise an incident surface and an emergent sur^¬ face, wherein the incident surface defines a receiving cav- ity. The LED chips can be disposed in the receiving cavity, and meanwhile, the respective lens parts form a sealing structure with the circuit board, then the LED chips disposed in the receiving cavity are isolated from the outside, thereby preventing pollutants from polluting the LED chips.

As put forward in the present invention, the incident surface and the emergent surface are designed so that the light from the LED chip passes through the first lens part or the second lens part and then covers at least a semispherical area. The incident surface and the emergent surface cooperate with each other so that the light emitted from the lens parts evenly covers the corresponding semispherical areas. Thus, the light intensity distribution in respective directions is consistent as much as possible while the omnidirectional illumination effect is obtained.

Preferably, the incident surface is designed to be a sphere, and the emergent surface is designed to be a free curved sur^¬ face. The mutual cooperation between the incident surface and the emergent surface is fine as long as it can ensure cover- ing one semispherical area, and designing the incident sur^¬ face as a sphere and designing the emergent surface as a free curved surface help the processing and producing. Of course, the designing personnel may also select other types of inci^¬ dent surfaces and emergent surfaces. As put forward in the present invention, the bearing struc^¬ ture is designed to be a heat sink. The circuit board is di^¬ rectly supported at the heat sink, which lowers the thermal resistance between the circuit board and the heat sink, and better helps heat dissipation and then improves the effi- ciency and the service life of the overall LED retrofit lamp. Advantageously, the heat sink comprises a base and fins formed at the circumferential surface of the base. The fins increase the convection area of the heat sink and the ambient environment and improves the heat dissipation effect of the heat sink.

As put forward in the present invention, the fins are de^¬ signed so that the heat sink at most shields a conical area of 60 degrees. As the fins protrude from the base at the outer circumference of the base and extend, the fins must shield the light emitted from the LED chips to a certain ex^¬ tent, if the shielding can be lowered within a minimum range, it will help the LED retrofit lamp much according to the pre^¬ sent invention. In the design solution of the present invention, the so-called conical area of 60 degrees refers to the rear semi sphere at the LED retrofit lamp, taking the optical center of the LED retrofit lamp as the top point, that is, a conical area in the area where the heat sink is located.

Preferably, the base is formed therein with a slot, and the circuit board is inserted into the slot in a form fitting manner. The slot can reliably fix the circuit board therein. In addition, as the circuit board is in tight contact with the slot, this helps much deliver the heat from the circuit board to the heat sink, which notably improves the heat dis^¬ sipation property of the LED retrofit lamp according to the present invention.

Advantageously, the lens is formed of plastic or glass. Of course, the lens can also be formed of other transparent or translucent materials.

It should be understood that, unless otherwise indicated, the features of the different explanatory embodiments described herein can be combined with each other. Brief Description of the Drawings

The accompanying drawings constitute a part of the present Description and are used to provide further understanding of the present invention. Such accompanying drawings illustrate the embodiments of the present invention and are used to de^¬ scribe the principles of the present invention together with the Description. In the accompanying drawings the same compo^¬ nents are represented by the same reference numbers. As shown in the drawings:

Fig. 1 is a schematic diagram of the LED retrofit lamp ac^¬ cording to the present invention;

Fig. 2 is a schematic diagram of the LED retrofit lamp not mounted with a lens; Fig. 3 is a schematic diagram of a circuit board area mounted with a lens;

Fig. 4 is a schematic diagram of the lens of the LED retrofit lamp according to the present invention;

Fig. 5 is a diagram of the distribution of the light emitted from one lens part of the lens; and

Fig. 6 is a diagram of the light path of the light emitted from the LED retrofit lamp according to the present invention.

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 specific embodiments are shown by way of illustration in which the present invention may be practiced. In this re^¬ gard, directional terminology, such as "upper", "lower", "left", "right", is used in reference to the orientation of the figures being described. Because components of embodi^¬ ments of the present invention can be positioned in a number of different orientations, the directional 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 depart^¬ ing from the scope of the present invention. The following detailed description, therefore, is not to be taken in a lim^¬ iting sense, and the scope of the present invention is de^¬ fined by the appended claims. Fig. 1 is a schematic diagram of the LED retrofit lamp 100 according to the present invention. Seen from the drawing, the LED retrofit lamp comprises: a bearing structure 1 de^¬ signed to be a heat sink; a circuit board 2 disposed at one side of the bearing structure 1; and a lens 3. From the draw- ing, the circuit board 2 is erected at one side of the bear^¬ ing structure 1, and comprises a first side 21 and a second side 22 facing each other and provided with an LED chip (not shown in the drawing) , respectively. If the extending direc^¬ tion of the circuit board 2 is the perpendicular direction, the LED chips are arranged at two sides of the circuit board 2 back to back in the horizontal direction perpendicular to the perpendicular direction.

In addition, further seen from the drawing, the lens 3 comprises a first lens part 31 and a second lens part 32 mounted at the first side 21 and the second side 22, wherein, the light from the LED chip passes through the first lens part 31 and the second lens part 32 respectively and then is exited. The first lens part 31 and the second lens part 32 sandwich the circuit board 2 therebetween.

Fig. 2 is a schematic diagram of the LED retrofit lamp 100 not mounted with the lens 3. The layout of the circuit board 2 and the heat sink can be seen more clearly from the drawing. As seen from the drawing, the heat sink comprises a base 11 and fins 12 formed at the circumferential surface of the base 11. Wherein, a slot 111 is formed in one side of the base 11, and the circuit board 2 is inserted into the slot 111 in a form fitting manner. The slot can reliably fix the circuit board therein. In addition, as the circuit board 2 is in tight contact with the slot, this helps much deliver the heat from the circuit board 2 to the heat sink, which notably improves the heat dissipation property of the LED retrofit lamp 100 according to the present invention.

In addition, the fins 12 are designed so that the heat sink at most shields a conical area of 60 degrees. As the fins 12 protrude from the base 11 at the outer circumference of the base 11 and extend the fins 12 must shield the light emitted from the LED chips to a certain extent, if the shielding can be lowered within a minimum range, it will help much the LED retrofit lamp much according to the present invention. In the design solution of the present invention, the so-called conical area of 60 degrees refers to the rear semi sphere at the LED retrofit lamp, taking the optical center of the LED ret^¬ rofit lamp as the top point, that is, a conical area in the area where the heat sink is located (referring to Fig. 1) .

Fig. 3 is a schematic diagram of the area of the circuit board 1 mounted with the lens 3, in which the part of the bearing structure 1 is not shown. Seen from the drawing, the lens 3 comprises the first lens part 31 and the second lens part 32 which sandwich the circuit board 2 therebetween.

Here, the circuit board 2 serves as the bearing body of the two lens parts, and seen from the direction of the drawing, the first lens part 31 and the second lens part 32 are re- spectively in tight connection with the circuit board 2 at two sides of the circuit board 2. The lens parts 31 and 32 can be adhered to or snapped to the circuit board 2.

Fig. 4 is a schematic diagram of the lens 3 of the LED retro^¬ fit lamp 100 according to the present invention. The drawing only illustrates the first lens part 31 and the second lens part 32 of the lens 3, and the circuit board 2 and the other structures are not shown. In this embodiment, the first lens part 31 and the second lens part 32 are mirror symmetric, that is to say, the two lens parts are mirror symmetric with respect to the circuit board 2 at two sides of the circuit board 2. Therefore, the light emitted from the two lens parts is also symmetric in the two corresponding semispherical ar^¬ eas. However, in other embodiments of the present invention, the two lens parts may not be mirror symmetric, thereby ob- taining desired illumination effect. In this situation, the light emitted from the two lens parts is not symmetric in re^¬ spective semispherical areas. In addition, in the embodiment of the present invention, the lens 3 is formed of plastic, and of course, the lens 3 can also be formed of glass or other transparent materials.

In addition, seen from the drawing, the first lens part 31 and the second lens part 32 respectively comprise an incident surface 311, 321 and an emergent surface 312, 322, wherein the incident surface 311, 321 defines a receiving cavity 313, 323, and the LED chips not shown in the drawing can be dis^¬ posed within the receiving cavity. According to a design solution of the present invention, the first lens part 31 and the second lens part 32 are designed so that the light from the LED chip passes through the first lens part 31 and the second lens part 32 and then covers the area at two sides of the circuit board 2 to achieve omnidi^¬ rectional illumination. Therefore, the incident surface 311, 321 and the emergent surface 312, 322 are designed so that the light from the LED chip passes through the first lens part 31 or the second lens part 32 and then covers at least a semispherical area. In this embodiment, the incident surface

311, 321 is designed to be a sphere, and the emergent surface

312, 322 is designed to be a free curved surface. The mutual cooperation between the incident surface 311, 321 and the emergent surface 312, 322 is fine as long as it can ensure covering one semispherical area, and designing the incident surface 311, 312 as a sphere and designing the emergent sur^¬ face 312, 322 as a free curved surface help the processing and producing. Of course, the designing personnel may also select other types of incident surfaces and emergent sur- faces.

Fig. 5 is a diagram of the distribution of the light emitted from one lens part of the lens 3 of the LED retrofit lamp 100 according to the present invention. Seen from the drawing, the light emitted from one lens part covers a semispherical area of nearly 180 degrees, then, if the LED retrofit lamp uses two such lens parts, the omnidirectional illumination effect can be achieved.

Fig. 6 is a diagram of the light path of the light emitted from the LED retrofit lamp 100 according to the present in- vention. Seen from the drawing, the light emitted from the LED retrofit lamp 100 nearly covers a spherical area of 360 degrees, while just does not cover some corner area in the lower part of the drawing, which is just like the description of Fig. 2, the light cannot cover such area due to the shielding of the base 11 and the fins 12 of the heat sink. However, for an omnidirectional illuminating device, the area covered by the LED retrofit lamp 100 of the present invention can completely meets the requirement of omnidirectional illu^¬ mination .

The above are merely preferred embodiments of the present in^¬ vention and are not intended to limit the present invention. For the person skilled in the art, the present invention may have various alterations and changes. Any alterations, equi^¬ valent substitutions, improvements, within the spirit and principle of the present invention, should be covered in the protection scope of the present invention.

Reference signs

bearing structure

11 base

12 fin

111 slot

circuit board lens

31 first lens part

32 second lens part 311_s 321 incident surface

321_% 322 emergent surface

Claims

An LED retrofit lamp, comprising: a bearing structure (1); a circuit board (2) arranged at one side of the bearing structure (1); and a lens (3), characterized in that, the circuit board (2) is erected at the bearing structure (1), and comprises a first side (21) and a second side (22) provided with at least one LED chip, respectively, the lens (3) comprises a first lens part (31) and a second lens part (32) mounted at the first side (21) and the second side (22), and the light from the LED chip passes through the first lens part (31) and the second lens part (32) respectively and then is ex^¬ ited .

The LED retrofit lamp (100) according to claim 1, characterized in that, the first lens part (31) and the sec^¬ ond lens part (32) sandwich the circuit board (2) there^¬ between .

The LED retrofit lamp (100) according to claim 1, characterized in that, the first lens part (31) and the sec^¬ ond lens part (32) are designed so that the light from the LED chip passes through the first lens part (31) and the second lens part (32) and then covers the area at two sides of the circuit board (2) to achieve omnidirec^¬ tional illumination.

The LED retrofit lamp (100) according to claim 3, characterized in that, the first lens part (31) and the sec^¬ ond lens part (32) are mirror symmetric with respect to the circuit board (2) .

5. The LED retrofit lamp (100) according to claim 4, char- acterized in that, the first lens part (31) and the sec^¬ ond lens part (32) respectively comprise an incident surface (311, 321) and an emergent surface (312, 322), wherein the incident surface (311, 321) defines a re^¬ ceiving cavity (313, 323) .

6. The LED retrofit lamp (100) according to claim 5, characterized in that, the incident surface (311, 321) and the emergent surface (312, 322) are designed so that the light from the LED chip passes through the first lens part (31) or the second lens part (32) and then covers at least semispherical area.

7. The LED retrofit lamp (100) according to claim 6, characterized in that, the incident surface (311, 321) is designed to be a sphere, and the emergent surface (312, 322) is a free curved surface.

8. The LED retrofit lamp (100) according to any of claims 1 to 7, characterized in that, the bearing structure (1) is heat sink.

9. The LED retrofit lamp (100) according to claim 8, characterized in that, the heat sink comprises a base (11) and fins (12) formed at the circumferential surface of the base (11).

10. The LED retrofit lamp (100) according to claim 9, characterized in that, the fins (12) are designed so that the heat sink (1) at most shields a conical area of 60 degrees .

11. The LED retrofit lamp (100) according to claim 8, characterized in that, the base (11) is formed therein with a slot (111), and the circuit board (2) is inserted into the slot (111) in a form fitting manner.

The LED retrofit lamp (100) according to any of claims 1 to 7, characterized in that, the lens (3) is formed of plastic or glass.