The present invention relates to a heat dissipating device having a linear heat dissipating unit and a fanless LED lamp using the device, in which the linear heat dissipating unit prevents air from remaining in one place in an environment without a fan and dissipates heat by natural convection ventilation, so that the effective heat dissipating area is remarkably large, thus very efficiently dissipating heat from electronic parts having a large heat generation load, such as lamps or industrial equipment, thereby allowing the installed equipment to be smoothly operated, increasing the life span of the equipment, and which removes a fan from the heat dissipating device, thus preventing noise pollution, and considerably reducing manufacturing costs.
Generally, an electronic part, such as a CPU (Central Processing Unit), a thermoelement, a VGA (Video Graphic Array) card, or an LED lamp generates a large quantity of heat during operation. When the electronic part or LED lamp exceeds proper temperature, an operational error may be male, and in addition, the electronic part or lamp may become broken or damaged. A heat dissipating device is essentially mounted to a heat generating part.
The preferable heat dissipating device must have a heat absorbing area which is sufficient to rapidly absorb heat from equipment, and a large heat dissipating area for rapidly dissipating the absorbed heat to the outside. Further, the heat dissipating device needs to be ventilated so as to prevent hot air from remaining in one place, thus smoothly discharging the hot air through the heat dissipating area to the atmosphere.
As shown in
When such a conventional heat dissipating device is in an environment where ventilation is performed, the surface area of the heat dissipating fins 131 serves as an effective heat dissipating area, thus smoothly dissipating heat.
However, in an environment where ventilation is not smoothly performed, the heat dissipating operation is performed owing to a difference between the temperature of the heat dissipating fins 131 and the surrounding temperature. The temperature difference between a lower point 101 contacting the heat absorbing part and an upper point 102 which is the farthest from the heat absorbing part is below 10% and the temperature difference between the heat dissipating fins 131 and gaps 104 between neighboring heat dissipating fins is below 10% (see
The larger the temperature difference between the heat dissipating fins 131 and the gaps 104 is, the higher the heat exchange efficiency for dissipating heat is. However, according to the prior art, a small difference in temperature between a point 106 of each heat dissipating fin 131 which is near to the heat absorbing part 110 and an upper point 107 which is distant from the heat absorbing part exists, so that the conventional heat dissipating device has a poor heat dissipating function.
This happens because air remains in the gaps 104 between the heat dissipating fins while remaining hot. Among the gaps 104 serving as the surface area of the heat dissipating fins 131, portions 105 other than an outermost portion 109, which is very shallow such that the air lightly touches the portion, substantially have no heat dissipating function (see
Thus, no matter how the surface area may be increased by the heat dissipating fins 131 and the gaps 104 in the environment which is not ventilated, the effective heat dissipating area is only five sides of each heat dissipating fin including four circumferential sides and the upper side, and part 109 of an inlet of a gap between neighboring heat dissipating fins, so that satisfactory heat dissipating performance is not achieved.
That is, in the conventional heat dissipating device which compactly arranges the heat dissipating fins, space occupied by the heat dissipating fins is large, and the air flow path contacting the heat dissipating fins is small, so that natural convection ventilation is not performed, and thus hot air remains in one place. Therefore, heat dissipating efficiency is low.
Further, since the volume of the heat dissipating fins is large, the costs of materials are wasted and the weight is heavy, thus making it difficult to achieve a light device.
In order to prevent hot air from remaining in one place, according to the prior art, a fan for forcibly blowing the air is essentially required.
However, such a fan causes noise pollution and dust, so that dust is deposited on the surface of each heat dissipating fin, and thus the performance of the heat dissipating device is reduced. Because of the increase in costs of the fan and the number of assembling processes caused by the additional part, manufacturing costs are increased.
Moreover, the heat dissipating function is lost when the fan is out of order, so that the expensive device may become damaged.
The dissipation of heat is very important in an LED lamp using an LED (Light Emitting Diode) as a light source.
The LED is smaller and has a longer life-span than the conventional light source, and directly converts electric energy into light energy, so that consumption of power is small, and energy efficiency is superior. However, unless heat is smoothly dissipated when the LED is turned on, the life-span of the LED is shortened, and luminous intensity is reduced. Thus, it can be concluded that the effective usage of the LED lamp is connected directly with the heat dissipating performance.
As shown in
Further, the heat dissipating means 230 includes heat dissipating fins 233 which are radially provided on the housing. The plurality of heat dissipating fins 233 which protrude vertically and gaps 231 between the heat dissipating fins are spaced at regular intervals, thus providing the cylindrical or conical heat dissipating means. Such a construction can exhibit sufficient heat dissipating effect due to the increase in the surface area resulting from the formation of the heat dissipating fins 233, as long as ventilation is smoothly performed.
However, under the environment where natural ventilation is not performed, for example when the lamp is installed in a recess formed in a ceiling, air remains in the gaps 231 between the heat dissipating fins, remaining hot. Thus, among the gaps 231 providing the surface area of the heat dissipating fins 233, portions 231a other than the outermost portion, which is very shallow such that the air lightly touches it, substantially have no heat dissipating function.
Thus, no matter how the surface area may be increased by the heat dissipating fins 233 and the gaps 231 under the environment which is not ventilated, the substantial effective heat dissipating area is not increased.
Further, a base and heat dissipating fins are concentrated on the PCB which is a heat generating source, so that the dissipated heat is mutually irradiated, and thereby heat dissipating efficiency is reduced.
In order to reduce thermal load due to the above heat dissipating problem, according to the prior art, a current which is lower than a rated current flows into the PCB. However, in this case, the brightness of the LED is reduced, so that the number of LEDs must be increased so as to meet a preset luminous intensity. Thereby, electric energy is wasted, and manufacturing costs are increased due to the increase in the number of LEDs.
Thus, according to the prior art, a fan is installed in a heat dissipating means.
However, the life-span of the LED is about 50,000 hours, whereas the life-span of the fan is only about 10,000 hours, so that the life-span of an LED lamp is considerably shortened and noise is generated because of the fan. Thus, it is impossible to use in a building demanding quiet.
Further, since dust is deposited on the surface of the heat dissipating means due to the blowing operation, heat dissipating efficiency is lowered.
Further, when the LED lamp is installed outdoors, water, insects, dust, etc. may enter the lamp through a blowing passage defined in the heat dissipating means, thus impairing the fan. Thus, it is impossible to install the LED lamp outdoors, like streetlamps, so that the area of installing an LED lamp becomes limited to the interior of a building which is insensitive to noise.
Accordingly, the present invention has been male keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a heat dissipating device having a linear heat dissipating unit and a fanless LED lamp using the device, in which the linear heat dissipating unit prevents air from remaining in one place in an environment without a fan and dissipates heat by natural convection ventilation, so that the effective heat dissipating area is remarkably large, thus very efficiently dissipating heat from electronic parts having a large heat generation load, such as lamps or industrial equipment, thereby allowing the installed equipment to be smoothly operated, increasing the life span of the equipment, and which removes a fan from the heat dissipating device, thus preventing noise pollution, and considerably reducing manufacturing costs.
Another object of the present invention is to provide a heat dissipating device having a linear heat dissipating unit and a fanless LED lamp using the device, in which ventilation is performed through natural convection, so that a fan can be removed from the heat dissipating device, thus preventing noise pollution and considerably reducing manufacturing costs.
In order to accomplish the above objects, the present invention provides a heat dissipating device having a heat dissipating bracket having a heat absorbing part, and a linear heat dissipating unit which is coupled to the heat dissipating bracket and has a coil shape achieved by the continuous winding of a wire into a spiral shape, wherein the heat dissipating bracket includes an insert hole which corresponds to part of the linear heat dissipating unit in such a way as to be in surface contact with the part of the linear heat dissipating unit, and the linear heat dissipating unit protrudes to an outside of the heat absorbing part of the heat dissipating bracket to perform a heat exchange process for dissipating heat through natural convection ventilation.
Further, in order to accomplish the above objects, the present invention provides a fanless LED lamp having a linear heat dissipating unit, which includes a light source unit having at least one LED (Light Emitting Diode) and an LED mounted PCB, a heat dissipating means attached to the LED mounted PCB to dissipate heat from the light source unit, and a housing connected to the heat dissipating means and having a power connection part, wherein the heat dissipating means includes the linear heat dissipating unit.
As described above, the heat dissipating device having the linear heat dissipating unit and the fanless LED lamp using the device according to the present invention are advantageous in that the linear heat dissipating unit prevents air from remaining in one place in an environment without a fan and dissipates heat by natural convection ventilation, so that the effective heat dissipating area is remarkably large, thus very efficiently dissipating heat from electronic parts having a large heat generation load, such as lamps or industrial equipment, thereby allowing the installed equipment to be smoothly operated and increasing the life span of the equipment.
Further, the present invention is advantageous in that natural convection ventilation is done, thus removing a fan from the heat dissipating device, thereby preventing noise pollution, and considerably reducing manufacturing costs.
1: heat dissipating device having a linear heat dissipating unit according to the present invention
2: fanless LED lamp having a linear heat dissipating unit according to the present invention
10: linear heat dissipating unit
10-1: ring-shaped element 11: heat absorbing part
20: heat dissipating bracket 21: heat absorbing part
23: insert hole
25: heat dissipating fin A: heat dissipating means
33: flange-type dissipater
35: fin-type dissipater 37: ventilation dissipater 50: housing 53: holding groove
60: support member
71: ring-shaped support member
Hereinafter, a heat dissipating device having a linear heat dissipating unit and a fanless LED lamp having the device according to the preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.
As shown in
The heat dissipating bracket 20 includes insert holes 23 which correspond to part of each linear heat dissipating unit in such a way that the heat dissipating bracket is in surface contact with the part of the linear heat dissipating unit 10. Each linear heat dissipating unit 10 protrudes to the outside of the heat absorbing part 21 of the heat dissipating bracket 20 to perform a heat exchange process for dissipating heat through natural convection ventilation.
Here, the configuration wherein each linear heat dissipating unit 10 protrudes to the outside of the heat absorbing part 21 of the heat dissipating bracket means the configuration of
Each linear heat dissipating unit 10 may have a coil spring shape 10a which is formed by winding a wire into a circular shape, a coil spring shape 10b (see
The wire used for the linear heat dissipating unit 10 has a circular- or plate-shaped cross-section (see
The linear heat dissipating unit 10 may be male of a material having high thermal conductivity, such as copper or aluminum coil.
Further, as shown in
In order to increase heat absorbing efficiency of the heat absorbing part 11, the standard winding parts D1 and the differential winding parts D2 have the same protruding length to contact with the heat dissipating bracket 20. The winding parts may have three or more dimensions (see
The linear heat dissipating unit 10 may include a plurality of ring elements 10-1 which are continuously arranged at predetermined intervals (see
Further, the inclination angles of the insert holes 23, which are in surface contact with a section of the linear heat dissipating unit 10, are increased in a direction distant from a center (see
Further, as shown in
The linear heat dissipating bracket 10 may be arranged in a zigzag or spiral shape.
The operation of the heat dissipating device 1 having the linear heat dissipating unit according to the present invention, which is constructed as described above, will be described below.
The linear heat dissipating unit 10 of the present invention, having the coil spring shape, protrudes to the outside of the heat absorbing part of the heat dissipating bracket, so that ventilation space is formed in the rising direction of an air current, that is, in a direction from a lower position to an upper position, so that air does not remain in one place, and ventilation by natural convection is smoothly performed. Thus, even in an environment where a fan is not installed, the heat exchanging operation is smoothly performed by natural convection ventilation, and an effective heat dissipating area as formed is remarkably large.
The surface area of the linear heat dissipating unit 10 is equal to the circumference of the section of the wire multiplied by the length of the coil. When the section of the wire has a circular shape, it is easy to plastically deform the wire into the coil spring shape. Further, the plate shape has higher heat dissipating efficiency than the circular shape.
For example, assuming that the sectional area of the wire is 3.14 mm2, the wire having the circular section has the radius r of 1 mm, with the circumference of the wire being 2πr=6.28 mm.
Assuming that the section of the wire has the shape of a thin rectangular plate of 0.5 mm×6.28 mm, the circumference of the rectangular plate is 13.56 mm. Thus, when the rod material has the section of the plate shape, the surface area is remarkably increased.
Further, when calculating the winding circumference and the pitch of the coil, the length of the linear heat dissipating unit 10 is very long.
Thus, the effective heat dissipating area for preventing air from remaining in one place is male to be remarkably large.
Further, when each linear heat dissipating unit 10 is formed such that parts having different winding dimensions are repeated (see
Further, the linear heat dissipating unit 10 is less heavy when compared to the effective heat dissipating area and affords a free change in arrangement, so that it is very easy to handle and hold, and the material used is considerably reduced.
The installation of each linear heat dissipating unit 10 to the heat dissipating bracket 20 will be described now. The linear heat dissipating unit is firmly fitted into the insert holes 23 formed in the heat dissipating bracket, and then secured to the heat dissipating bracket using the support member 60. In this way, the assembly is completed in a simple manner. The linear heat dissipating unit 10 may be welded to the heat dissipating bracket 20.
The operational effects of the present invention will be summarized as follows.
First, the heat dissipating area is maximized owing to the linear heat dissipating unit.
Second, the insert holes 23 are formed in the heat dissipating bracket 20 to increase a contact surface with the linear heat dissipating unit, so that a sufficient heat absorbing area for absorbing heat is ensured.
Third, the linear heat dissipating unit 10 protrudes outside of the heat dissipating bracket 20, so that ventilation and natural convection of rising hot air are smoothly performed, and thus heat exchanging operation for radiating heat to the atmosphere is effectively performed.
That is, due to the insert holes in the heat dissipating bracket, sufficient heat absorbing performance is ensured. Further, the linear heat dissipating unit protrudes to the outside of the heat dissipating bracket to be located in space which is ventilated through natural convection, so that smooth ventilation is possible without a blowing fan. Thereby, the three factors determining the quality of the heat dissipating device are perfectly satisfied.
Thus, the present invention exhibits superior performance as a heat dissipating means for equipment having high heat generation load, such as an electronic part, including a CPU, a thermoelement, or a VGA card, a lamp, and industrial equipment, thus allowing the installed equipment to be smoothly operated, and increasing the life-span of the equipment.
Further, the present invention can omit the fan which is essential for the conventional heat dissipating device, thus preventing noise from being generated, reducing costs of parts and the number of processes required to assemble the parts, therefore reducing manufacturing costs.
As shown in
Here, a holding groove 53 having a predetermined pitch is formed in the outer circumference of a dissipater of the heat dissipating means A or the housing 50 to hold the linear heat dissipating unit 10. The linear heat dissipating unit 10 may be arranged in a circular shape along the outer circumference of the dissipater of the heat dissipating means A or the housing 50 using the holding groove 53.
The dissipater of the heat dissipating means A, which has the holding groove 53 in the outer circumference of the dissipater, is a heat dissipating bracket which is provided to contact the LED mounted PCB 93. A flange-type dissipater 33, a fin-type dissipater 35, and a ventilation dissipater 37, which will be described below, belong to the dissipater.
The holding groove 53 may be shaped such that an inlet 531 formed in the upper portion of the holding groove is large and the holding groove is gradually tapered in a direction from an upper position to a lower position, thus affording the easy insertion of the linear heat dissipating unit 10, and preventing the unexpected removal of the linear heat dissipating unit. Preferably, the holding groove has the function of holding the linear heat dissipating unit and is in surface contact with the linear heat dissipating unit.
In order to form the holding groove 53, the thickness of the housing 50 is increased.
According to an embodiment of the present invention, the dissipater of the heat dissipating means A may comprise a flange-type dissipater 33 having a heat absorbing part 331 which contacts the LED mounted PCB 93, and a flange 333 which protrudes outwards from the heat absorbing part 331 and supports part of the linear heat dissipating unit 10.
The flange-type dissipater 33 may include insert holes 335 which are radially formed to correspond to part of the linear heat dissipating unit 10, so that part of the linear heat dissipating unit 10 is in surface contact with the dissipater (see
Further, the linear heat dissipating unit 10 also includes a ring-shaped support member 71 which passes through the interior of the linear heat dissipating unit (see
The support member 71 may be made of a metal material or an elastic material, such as an elastic cord.
According to an embodiment of the present invention, as shown in
The fin-type dissipater 35 is similar to a conventional dissipater except that inside portions of the gaps 355 of the heat dissipating fins are in surface contact with the linear heat dissipating unit 10.
According to an embodiment of the present invention, as shown in
The ventilation dissipater 37 is mainly used for a high output LED lamp, and is constructed so that the LED mounted PCB 93 and the power supply unit PCB 95 are spaced apart from each other, thus allowing air to circulate between the LED mounted PCB and the power supply unit PCB. The linear heat dissipating unit 10 is connected to the ventilation dissipater using slots 378.
Upper and lower ends 3782 of the slots are formed to correspond to the shape of the wound liner heat dissipating unit 10, so that the slots 378 are in surface contact with a heat dissipating coil.
The installation and operation of the fanless LED lamp 2 having the linear heat dissipating unit according to the present invention, constructed as described above, will be described below.
When the linear heat dissipating unit 10 is installed at the LED lamp, the linear heat dissipating unit may be directly mounted to the LED mounted PCB 93. However, as described above, preferably, the linear heat dissipating unit is installed to the dissipater of the heat dissipating means A, such as the flange-type dissipater 33, the fin-type dissipater 35, or the ventilation dissipater 37, contacting the LED mounted PCB 93, in such a way as to be in surface contact with the dissipater.
When the linear heat dissipating unit 10 is fitted into the holding groove 53 formed in the housing and is lightly pushed, the lower end of the linear heat dissipating unit, that is, the heat absorbing part 11 is firmly fitted into the insert holes 335 of the flange-type dissipater, so that the assembly is completed in a simple manner. The undesirable removal of the linear heat dissipating unit is prevented by the holding groove 53.
Further, in the case of using the additional support member 71, the support member 71 is put into the heat dissipating coil. In such a state, in the case of the flange-type dissipater 33, part of the linear heat dissipating unit 10 is placed in the insert holes 335, and the support member 71 is fastened in the ring shape and is fastened to the flange-type dissipater 33 using fastening members 73 (see
Further, in the fin-type dissipater 35 or the ventilation dissipater 37, firm fastening operation is possible only by the support member 71.
According to the present invention, the linear heat dissipating unit 10 is provided on the LED lamp, thus preventing air from remaining in one place, and dissipating heat through natural convection ventilation, therefore allowing the high output LED lamp having a large heat generation load to smoothly dissipate heat generated when the LED is turned on, without using a fan.
Hereinbefore, the preferred embodiments of the present invention have been described with reference to the accompanying drawings. Here, the terminologies or words used in the description and the claims of the present invention should not be interpreted as being limited merely to common and dictionary meanings, but should be interpreted based on the meanings and concepts of the invention in keeping with the scope of the invention. Therefore, although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.
As described above, the present invention provides a heat dissipating device having a linear heat dissipating unit and a fanless LED lamp using the device, in which the linear heat dissipating unit is provided so that natural convection ventilation is done in an environment without a fan, thus preventing air from remaining in one place, and the effective heat dissipating area is remarkably large, thus very efficiently dissipating heat from electronic parts having a large heat generation load, such as lamps or industrial equipment, thereby allowing the installed equipment to be smoothly operated and increasing the life span of the equipment.
Further, according to the present invention, natural convection ventilation is smoothly done, thus removing a fan from the heat dissipating device, thereby preventing noise pollution, and reducing manufacturing costs.
Number | Date | Country | Kind |
---|---|---|---|
10-2007-0067755 | Jul 2007 | KR | national |
10-2007-0071536 | Jul 2007 | KR | national |
10-2007-0071537 | Jul 2007 | KR | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/KR08/03870 | 7/1/2008 | WO | 00 | 12/31/2009 |