WO2008123711A1

WO2008123711A1 - Led lighting apparatus

Info

Publication number: WO2008123711A1
Application number: PCT/KR2008/001929
Authority: WO
Inventors: Man Jae Choi
Original assignee: Lumisys Co., Ltd.
Priority date: 2007-04-05
Filing date: 2008-04-04
Publication date: 2008-10-16
Also published as: KR100754973B1

Abstract

A Light Emitting Diode (LED) lighting apparatus relating to a Light Emitting Diode (LED) lighting apparatus, and more particularly, to an LED lighting apparatus using an LED as a lighting source, the LED lighting apparatus comprising: a body including a block having a plurality of inclined surfaces at parts except a central plane, a coupling portion installed at a side surface of the block so as to be installed at a lighting source mounting mechanical part, and a substrate detachably assembled to each surface of the body and having a connection circuit pattern for electrical connection of LED devices; and one or more LED devices mounted to each of the substrates, is disclosed.

Description

LED LIGHTING APPARATUS

Technical Field

[1] The present invention relates to a Light Emitting Diode (LED) lighting apparatus, and more particularly, to an LED lighting apparatus using an LED as a lighting source. Background Art

[2] Generally, street lamps indicate lamp facilities installed along pedestrian roads or vehicle roads for street lamps or traffic safety.

[3] As a lighting source, the street lamp uses the conventional mercury lamp or a fluorescent lamp or a sodium lamp mounted to a lamp mechanical part. The street lamp is made to be lightened when power is supplied thereto by a power supply device, and when operated by a timer and a central controller. Accordingly, areas adjacent to the street lamp can be lightened with illumination more than a certain level. Recently, the street lamp uses a Light Emitting Diode (LED) having less power consumption and semi-permanent lifespan as a lighting source, so as to enhance illumination and reduce power consumption.

[4] Referring to FIG. 1, when a street lamp 1 is installed at a height distant from the ground by 10m, side illumination occurring at 'B' and 'C distant from 'A' by 10m in right and left directions has to be a predetermined reference value (e.g., 20Lux). Here, the 'A' is ground below the height of the street lamp 1.

[5] The LED being widely used as a lighting source has an excellent characteristic when compared with other lighting sources in the aspect of power consumption and illumination. However, when the LED is mounted to a half-circle or a spherical shaped mechanical part, it is difficult to illuminate the side surfaces, 'B' and 'C up to 20Lux , because the LED mainly emits a straight lighting source.

[6] Furthermore, when the conventional LED street lamp is out of order, an LED mounting mechanical part has to be wholly replaced, and an LED that can be used has to be discarded. Accordingly, costs for maintaining and repairing the LED street lamp increase.

Disclosure of Invention

Technical Problem

[7] Therefore, it is an object of the present invention to provide an LED lighting apparatus capable of enhancing illumination of light emitted from a lighting source not only in a downward direction but also in side directions.

[8] Anther object of the present invention is to provide an LED lighting apparatus capable of reducing costs for maintenance and repair by partially replacing a lighting source not wholly when the LED lighting apparatus is out of order.

[9] Still another object of the present invention is to provide an LED lighting apparatus capable of reducing costs for maintenance and repair and having a long lifespan. Technical Solution

[10] To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is provided a Light Emitting Diode (LED) lighting apparatus, comprising: a body including a block having a plurality of inclined surfaces at parts except a central plane, a coupling portion installed at a side surface of the block so as to be installed at a lighting source mounting mechanical part, and a substrate detachably assembled to each surface of the body and having a connection circuit pattern for electrical connection of LED devices; and one or more LED devices mounted to each of the substrates.

[11] To achieve these objects of the present invention, there is also provided a Light

Emitting Diode (LED) lighting apparatus, comprising: a body coupled to a lighting source mounting mechanical part, the body having a convex polygonal body, in which one or more LEDs are mounted on each surface of the polygonal body.

Advantageous Effects

[12] In the LED lighting apparatus according to the present invention, light is emitted from LED devices to side surfaces by constructing a part of mounting surfaces for the LED devices to be inclined, thereby implementing side illumination more than a reference level.

[13] Also in the LED lighting apparatus according to the present invention, aluminum material having high thermal conductivity or conductive thermoplastic is used to enhance heat emission effect from LED devices, thereby preventing loss and damage of the LED devices and enhancing lifespan and illumination of the LED devices.

[14] Also in the LED lighting apparatus according to the present invention, LED devices installed at a street lamp have a structure to be partially replaced, thereby enhancing convenience when replacing a lighting source, and facilitating to maintain and repair the street lamp.

[15] Also in the LED lighting apparatus according to the present invention, some of the

LED devices are prevented from mal-operating owing to an efficient circuit design. Also, the LED devices are protected thus to prolong a lifespan, to enhance illumination, and to reduce power consumption with low costs. Brief Description of the Drawings

[16] FIG. 1 is a conceptual view for explaining side illumination of a street lamp;

[17] FIG. 2 is a plane view of an LED street lamp according to the present invention;

[18] FIG. 3 is a view of a polygonal frame of the LED street lamp according to the present invention; [19] FIG. 4 is a side sectional view of the LED street lamp according to the present invention; [20] FIG. 5 is a sectional view of a lighting source mounting substrate according to the present invention; [21] FIG. 6 is a view showing a circuit composition of an LED lighting source according to the present invention; and [22] FIG. 7 is a view showing a side emission concept of the LED street lamp according to the present invention.

Mode for the Invention [23] Hereinafter, an LED lighting apparatus according to the present invention will be explained in more detail with reference to the attached drawings. [24] FIG. 2 is a plane view of an LED street lamp according to the present invention, FIG.

3 is a view of a polygonal frame of the LED street lamp according to the present invention, FIG. 4 is a side sectional view of the LED street lamp according to the present invention, FIG. 5 is a sectional view of a lighting source mounting substrate according to the present invention, FIG. 6 is a view showing a circuit composition of an LED lighting source according to the present invention, and FIG. 7 is a view showing a side emission concept of the LED street lamp according to the present invention. [25] As shown in FIGS. 1 to 7, an LED lighting apparatus 100 according to the present invention is mounted to a street lamp, and comprises a body 110 coupled to a lighting source mounting mechanical part 101, and having a convex polygonal body. Here, one or more LEDs devices 130 are mounted on each surface of the polygonal body. [26] The polygonal body formed by the body 110 may have various shapes such as a polygonal pyramid and a truncated polygonal pyramid. For an instance, as shown in

FIG. 2, the polygonal body may include a central plane (a), and a plurality of inclined surfaces (b, c, d, e) inclined from the central plane (a). [27] The body 110 may include a plurality of substrates forming respective surfaces (a, b, c, d, e) of the polygonal body by being coupled to each other, and having one or more

LED devices 130 mounted thereto. [28] The body 110 may further include a frame 115 forming a polygonal body and supporting a plurality of substrates 120. [29] The body 110 is provided with one plane, and inclined surfaces inclined from the one plane. The body 110 may be implemented as two or more polygonal bodies inclined from each other. [30] Hereinafter, a preferred embodiment of the LED lighting apparatus according to the present invention will be explained in more detail with reference to the attached drawings.

[31] As shown in FIGS. 2 to 7, the body 110 has a truncated polygonal pyramid. The body 110 may include a block 111 having a central plane (a) and a plurality of inclined surfaces (b, c, d, e); and a substrate 120 detachably coupled to each surface (a, b, c, d, e) of the body 110, and having a connection circuit pattern for electrical connection among the LED devices 130.

[32] The block 111 is a member to install the substrate 120 thereon or to support the substrate 120, and may have various shapes such as a frame shape to install the substrate 120 thereon, or a plate shape to absorb heat generated from the substrate 120. The block 111 may be integrally formed or may be configured as a plurality of members to which each surface of a polygonal body is detachably coupled.

[33] Here, the block 111 and the substrate 120 are respectively provided with coupling holes 113, 120a in correspondence with each other, thereby being coupled to each other by a coupling member 150 such as bolts and nuts.

[34] The inclined surfaces (b, c, d, e) of the polygonal body are inclined from the central plane (a), and may have inclination angles of 10°~ 40°.

[35] The reason why the inclined surfaces (b, c, d, e) have inclination angles of 10°~ 40° is in order to enhance side illumination by distributing light straightly emitted from the LED devices to side surfaces.

[36] When the inclined surfaces (b, c, d, e) have inclination angles less than 10°, a side distance to which light from the LED devices can reach is short and side illumination is low. On the contrary, when the inclined surfaces (b, c, d, e) have inclination angles more than 40°, a side distance to which light from the LED devices can reach is long but side illumination is low.

[37] Therefore, the inclined surfaces (b, c, d, e) of the block 110 are most preferably formed to be inclined by 20°.

[38] For high thermal conductivity, the block 111 is formed of aluminum material (Al) or conductive thermoplastic. Although the block 111 is illustrated to have a truncated tetragonal pyramid having a five surfaces, it may have various structures such as a truncated hexagonal pyramid, a truncated octagonal pyramid, a tetragonal pyramid, a pentagonal pyramid, and an octagonal pyramid, and various modifications.

[39] As the substrate 120, a printed circuit board (PCB) having a circuit pattern for coupling the LED devices 130 may be used. The substrate 120 may be formed of various materials, and may have various structures according to design conditions.

[40] The substrate 120 may include a base plate formed of aluminum material or conductive thermoplastic; a circuit pattern layer 122 formed of an epoxy material, disposed on an upper surface of the base plate 121, and having a circuit pattern for connection with the LED devices 130; a conductive layer 123 coated on a rear surface of the base plate 121 by a conductive adhesive so as to enhance thermal conductivity; and a waterproof layer 124 formed of a silicon material, disposed on an upper surface of the circuit pattern layer 122, and configured to implement humidity or water proofing functions.

[41] Here, the conductive thermoplastic applied to the block 111 and the base plate 121 of the substrate 120 is a material applied to electronic appliances such as a motor and a heat spreader requiring a heat emitting function due to heat occurring therein. The conductive thermoplastic has excellent thermal transfer speed, and has nearly the same thermal conductivity as that of metal.

[42] The body 110 may be further provided with a coupling portion 112 at a side surface of the block 111 so as to be easily coupled to the lighting source mounting mechanical part 101.

[43] The LED device 130 may be installed on the substrate in one or more in number, various devices such as an LED device for emitting single color light or an LED device for emitting three color light may be used.

[44] A plurality of LED devices 130 may be arranged in a constant gap therebetween. As shown in FIG. 6, the LED devices 130 may have a serial and parallel structure by connecting in parallel a first LED group 131 having two or more LED devices serially connected, and a second LED group 132 having two or more LED devices serially connected.

[45] Accordingly, when the first LED group 131 is out of order to be turned off, the second LED group 132 can maintain an 'ON' state. Here, the LED groups 131 and 132 may be implemented as three or more LED groups rather than two, and the respective LED groups 131 and 132 may be installed on the plurality of substrates 120.

[46] A temperature sensor 140 for sensing a surface temperature of the body 110 and preventing the LED devices 130 from being thermally degraded by reducing current that flows to the LED devices 130 may be further installed on a central part of a rear surface of the body 110.

[47] The LED devices 130 and the temperature sensor 140 may receive power from a power supply device 103 for supplying power to the LED lighting apparatus 100, and may be controlled by a controller (not shown) such as a central controller.

[48] Here, the power supply device 103 may be installed at the body 110, and may be installed in the supporting plate 102 for supporting the lighting source mounting mechanical part 101 at a certain height.

[49] Operation of the LED lighting apparatus according to the present invention will be explained in more detail.

[50] The plurality of LED devices 130 are mounted to the plurality of substrates 120 along the circuit pattern 121 formed at the substrates 120, thereby completing a first assembly. Then, the plurality of substrates 120 having the LED devices 130 mounted thereon are coupled to each outer side surface of the block 111 of the body 110, thereby completing a secondary assembly.

[51] The body 110 having completed the secondary assembly is coupled to the lighting source mounting mechanical part 101 by the coupling portion 112, so that the LED devices 130 can be operated by a controller (not shown) and can be supplied with power by the power supply device 103.

[52] When the installed LED lighting apparatus 100 is turned ON, the LED devices 130 electrically connected to each other are turned ON to emit light.

[53] Here, the LED devices 130 mounted to the central plane (a) and the inclined surfaces

(b, c, d, e) of the body 110 based on the substrates 120 emit light mainly in a straight line direction due to their emitting characteristics. However, since the LED devices 130 are arranged on an inclined surface, light from a lighting source is forwardly and straightly emitted in all side directions. Furthermore, by controlling inclination angles of the inclined surface according to a size of an installation space, the LED devices 130 from which light is straightly emitted is made to emit light in facing directions. Besides, the LED devices are mounted on an outer side surface of the body 110, thereby preventing light emitted to the body 110 or the lighting source mounting mechanical part 101 from being shielded. Light emitted from the LED devices is completely emitted in a straight line direction, thereby implementing side illumination more than 20Lux. Also, the LED devices mounted to the central plane (a) of the body 110 is straightly emitted in a downward direction, thereby implementing illumination of a central part.

[54] When the LED devices 130 are turned ON or OFF, the temperature sensor 140 installed at the body 110 checks a surface temperature of the body 110 resulting from light emission from the LED devices 130. When a detected surface temperature of the body 110 exceeds 6O⁰C, the detected signal is transmitted to the controller. Then, the controller reduces current that flows to the LED devices 130, thereby preventing the LED devices from being thermally damaged and enhancing lifespan of the LED devices.

[55] In the present invention, the body 110 and the base plate 121 of the substrate 120 are formed of aluminum material having high thermal conductivity, or conductive thermoplastic. Accordingly, heat occurring when the LED devices 130 are turned ON or OFF is dissipated and emitted to outside, thereby minimizing loss and damage of the LED devices 130 due to heat. Therefore, the LED devices can have long lifespan and maintain illumination for a long time, thereby substantially enhancing illumination.

[56] In the present invention, the LED devices 130 have a serial and parallel structure between the first LED group 131 and the second LED group 132. Accordingly, even if the first LED group 131 is turned OFF, the second LED group 132 can maintain a turned ON state without being influenced by the first LED group 131. As a result, entire illumination is prevented from being suddenly turned OFF or weakened.

[57] In the present invention, the substrates 120 are implemented as individual substrates in correspondence with each polygonal surface of the body 110, thereby being detachably coupled to each other. Accordingly, when illumination is not uniform due to inferiority of the LED devices 130, the LED lighting apparatus 100 can be partially replaced, thereby reducing costs, enhancing a user's convenience, and facilitating maintenance and repair.

[58] As the present features may be embodied in several forms without departing from the characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be construed broadly within its scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalents of such metes and bounds are therefore intended to be embraced by the appended claims.

Claims

[1] A Light Emitting Diode (LED) lighting apparatus, comprising: a body including a block having a plurality of inclined surfaces at parts except a central plane, a coupling portion installed at a side surface of the block so as to be installed at a lighting source mounting mechanical part, and a substrate detachably assembled to each surface of the body and having a connection circuit pattern for electrical connection of LED devices; and one or more LED devices mounted to each of the substrates. [2] The LED lighting apparatus of claim 1, wherein a temperature sensor for sensing surface temperature of the body and preventing the LED devices from being thermally degraded by reducing current that flows to the LED devices is further installed on a central part of a rear surface of the body. [3] The LED lighting apparatus of claim 1, wherein the body is formed of aluminum, aluminum alloy, or conductive thermoplastic. [4] The LED lighting apparatus of claim 1, wherein the substrates comprises: a base plate; a circuit pattern layer disposed on an upper surface of the base plate, and having a circuit pattern for connection with the LED devices; a conductive layer coated on a rear surface of the base plate by a conductive adhesive so as to enhance thermal conductivity; and a waterproof layer disposed on an upper surface of the circuit pattern layer, and configured to implement humidity or water proofing functions. [5] The LED lighting apparatus of claim 1, wherein the inclined surfaces of the body have inclination angles of 10°~ 40° from the central plane. [6] A Light Emitting Diode (LED) lighting apparatus, comprising: a body coupled to a lighting source mounting mechanical part, the body having a convex polygonal body, in which one or more LEDs are mounted on each surface of the polygonal body. [7] The LED lighting apparatus of claim 6, wherein the polygonal body of the body comprises a central plane, and a plurality of inclined surfaces inclined from the central plane. [8] The LED lighting apparatus of claim 6, wherein the polygonal body is a truncated polygonal pyramid shape. [9] The LED lighting apparatus of claim 6, wherein the polygonal body is a polygonal pyramid shape. [10] The LED lighting apparatus of claim 6, wherein the body includes a plurality of substrates coupled to each other to form each surface of the polygonal body, and having one or more LED devices mounted thereon. [11] The LED lighting apparatus of claim 6, wherein the body further comprises a frame forming a polygonal body and supporting a plurality of substrates. [12] The LED lighting apparatus of claim 6, wherein the LED devices form a plurality of LED groups connected in parallel, each LED group having a plurality of LED devices connected in series. [13] The LED lighting apparatus of claim 12, wherein the LED groups are installed on the plurality of substrates, respectively. [14] The LED lighting apparatus of claim 12, wherein the LED groups are installed on the plurality of substrates, respectively. [15] The LED lighting apparatus of claim 12, wherein the polygonal body is composed of two planes having an inclination angle therebetween.