JP6202363B2 - Lighting device - Google Patents

Description

  The present invention relates to an illuminating device including a semiconductor light emitting element such as an LED as a light source, and more particularly to a technique for achieving both heat dissipation characteristics and space efficiency.

2. Description of the Related Art In recent years, lighting devices including semiconductor light emitting elements such as LEDs (Light Emitting Diode) as light sources have been adopted.
In FIG. 12, the illuminating device 9 which concerns on a prior art is shown. The lighting device 9 is a hanging type lighting device, and includes a cable 96 and an LED module 94 attached to the lower end of the cable 96. Further, in the lighting device 9, the shade 92 arranged so as to cover the periphery of the LED module 94, the phosphor layer 93 formed on the inner surface side of the shade 92, and the reflection provided below the LED module 94. A mirror 95 is also provided.

  When the lighting device 9 is driven to emit light, the light emitted from the LED module 94 is reflected by the reflecting mirror 95 and applied to the phosphor layer 93. The irradiated light is wavelength-converted by the phosphor layer 93 and is emitted toward the opening side (lower side) of the shade 92.

JP 2010-520604 A JP2012-14900A

  In an illuminating device including a semiconductor light emitting element such as an LED as a light source, it is important from the viewpoint of extending the device life to dissipate heat from the light source with high efficiency during light emission driving. In particular, in a high-power type illuminating device that emits light with high luminance, heat dissipation efficiency is an important factor. For this reason, conventionally, a method has been adopted in which a heat sink is thermally coupled to the semiconductor light emitting element to realize heat dissipation with high efficiency.

However, the higher the output, the greater the amount of heat that needs to be dissipated. However, it is not preferable to increase the size of the heat sink because of this increase in the size of the apparatus.
The present invention has been made to solve the above-described problems, and can radiate heat generated in a semiconductor light-emitting element with high efficiency and can suppress an increase in size. The purpose is to provide.

Thus, a lighting device according to one embodiment of the present invention includes a semiconductor light emitting element, a base, a heat sink, and a case.
The base has a plate shape, and a semiconductor light emitting element is arranged on one surface. The heat sink is arranged on the other surface of the base. The case has a cylindrical shape, and one opening is sealed by the base in a state where the heat sink is housed inside the cylinder.

  In the lighting device according to one embodiment of the present invention, each of the case and the base is provided with a vent hole communicating with the inner space of the case in which the heat sink is accommodated. In addition, the heat sink has a plurality of fins that are erected with respect to the other surface of the base and are disposed so as to surround the cylindrical shaft of the case. Each of the plurality of fins has at least a base side on the main surface with respect to an imaginary straight line passing through the cylinder axis of the case and the center in the width direction of the fin in a cross section orthogonal to the cylinder axis of the case. The root portion of each is arranged so as to intersect in an oblique direction.

  In the illuminating device which concerns on the said aspect, while being able to thermally radiate the heat which arises with a semiconductor light-emitting element with high efficiency, the enlargement of a size can be suppressed.

The schematic perspective view which shows the external appearance of the illuminating device 1 which concerns on embodiment of this invention. The schematic perspective view which shows the external appearance of the illuminating device 1 from diagonally upward. FIG. 3 is a schematic exploded perspective view showing the internal configuration of the lighting device 1. The model perspective view which extracts and shows the module plate 3, the outer heat sink 8, the inner heat sink 9, and the support pipe 6 among the structures of the illuminating device 1. FIG. FIG. 4 is a schematic plan view showing the arrangement of the heat dissipating fins 8b of the outer heat sink 8 and the heat dissipating fins 9b of the inner heat sink 9 with respect to the module plate 3; FIG. 3 is a schematic cross-sectional view showing the flow of air in the lighting device 1. (A) is a schematic plan view which shows the shape of the radiation fin 8b, (b) is a schematic plan view which shows the arrangement | positioning form of the radiation fin 8b with respect to the module plate 3. FIG. The characteristic view which shows the fin angle dependence of the fin heat dissipation. The schematic plan view which shows the relationship between angle (theta) of the radiation fin 8b, and each dimension. The characteristic view which shows the relationship between angle (theta) of the radiation fin 8b, and the number of the radiation fins 8b which can be formed. The characteristic view which shows the heat radiation amount which considered the number of the radiation fins 8b which can be formed. The schematic cross section which shows the structure of the hanging type illuminating device 9 which concerns on a prior art.

Hereinafter, lighting devices according to embodiments of the present invention will be described with reference to the drawings.
(Overall configuration of lighting device 1)
1-3, let the direction shown by the arrow Y be the back, and let the opposite side be the front. In the illuminating device 1, light is mainly emitted forward.
As shown in FIGS. 1 to 3, the lighting device 1 according to the present embodiment includes a module plate (base) 3, a plurality (six) of light emitting modules 4 arranged on the front surface of the module plate 3, and a module plate. 3 is provided with a support pipe 6 extending rearward from the central portion of 3.

As shown in FIG. 3, in the lighting device 1, an outer heat sink 8 and an inner heat sink 9 are attached behind the module plate 3. Both the outer heat sink 8 and the inner heat sink 9 are arranged so as to surround the support pipe 6.
As shown in FIGS. 1 to 3, the lighting device 1 includes a cylindrical case 2 that extends rearward from the outer edge 3 e of the module plate 3 and covers the outer heat sink 8 and the inner heat sink 9. Yes.

An attachment portion 7 that is a member for attaching the support pipe 6 to a construction material (ceiling, wall, etc.) is attached to the rear end portion of the support pipe 6.
On the other hand, as shown in FIGS. 1 and 3, a cover 5 that covers the plurality of light emitting modules 4 is attached to the front surface of the module plate 3.
The lighting device 1 according to the embodiment of the present invention is attached to a construction material such as a gymnasium, a factory, or a ceiling of a warehouse, and is used as a lighting device instead of an HID lamp.

(Case 2)
The case 2 has a cylindrical shape as a whole, the opening on the front side has substantially the same diameter as the outer edge of the module plate 3, and the opening on the rear side has substantially the same diameter as the outer diameter of the support pipe 6. Yes. As shown in FIG. 3, the case 2 surrounds the outer heat sink 8 and the inner heat sink 9.

  In the case 2, the opening 2 a on the front side is fixed to the outer edge 3 e of the module plate 3 by caulking. Therefore, the opening 2 a of the case 2 is in a state sealed by the module plate 3. For example, the case 2 and the support pipe 6 are fixed to each other by installing a pipe clamp at an opening edge through which the support pipe 6 in the case 2 is inserted and fastening the support pipe 6 with the pipe clamp.

On the rear end side of the case 2, a vent hole 2 c for opening air between the inner side and the outer side of the case 2 is opened. In addition, beads 2b for increasing the surface area and increasing the strength are formed at equal intervals on the side periphery of the case 2.
The height of the case 2 in the Y-axis direction is, for example, 270 mm, and the plate thickness is, for example, 1 mm.

(Module plate 3)
The module plate 3 is a disk-shaped member made of a heat conductive material (a material having a high heat conductivity). Examples of the material used for forming the module plate 3 in the present embodiment include metals such as aluminum and magnesium or alloys thereof.

  As shown in FIG. 3, a fitting hole 3 a into which a front end portion 6 a (see FIG. 1) of the support pipe 6 is fitted is formed at the center of the module plate 3. A region 3b for attaching a plurality of light emitting modules 4 around the fitting hole 3a is secured on the front surface of the module plate 3, and a plurality of ventilation holes 3c are provided in the outer circumferential portion of the module plate 3 along the circumferential direction. They are arranged in a ring.

Each air hole 3c is formed by punching the plate material of the module plate 3, and a bridge 3d is formed between adjacent air holes 3c.
In the present embodiment, the diameter of the module plate 3 is, for example, 260 mm, and the plate thickness is, for example, 2.0 to 2.5 mm.
(Light emitting module 4)
As described above, a plurality (six) of light emitting modules 4 are fixed in a ring shape in the region 3 b of the module plate 3. These light emitting modules 4 are arranged at an angle of 60 ° around the fitting hole 3a.

Although not shown, each light emitting module 4 includes a module substrate and a light emitting unit formed on the module substrate. The module substrate is formed of, for example, a glass composite material, and a wiring pattern for supplying power to the light emitting unit is formed on the surface of the module substrate.
The light emitting unit includes a plurality of LEDs (Light Emitting Diodes) and a sealing layer arranged to cover the LEDs. The LED is a COB (Chip on Board) type semiconductor light emitting element, and the sealing layer includes a phosphor that converts part of blue light emitted from the LED into yellow light.

Each light emitting module 4 is attached to the region 3b of the module plate 3 in a thermally coupled state using screws, a silicone adhesive, or the like.
(Cover 5)
As shown in FIGS. 1 and 3, the cover 5 is attached to the module plate 3 so as to cover the plurality of light emitting modules 4 arranged in the region 3b of the module plate 3 as a whole. The main surface portion 5a of the cover 5 has a Fresnel lens structure, condenses the light emitted from the plurality of light emitting modules 4, and emits the light forward.

The cover 5 has an edge of the peripheral edge 5b fixed to the module plate 3 with an adhesive or the like.
The cover 5 is formed using a transparent resin material such as an acrylic resin, polyethylene terephthalate, or polycarbonate.
(Support pipe 6)
The support pipe 6 is a straight pipe formed of a material having good heat conductivity (for example, a metal such as stainless steel). The support pipe 6 has a front end 6a (see FIG. 1) inserted into the fitting hole 3a of the module plate 3 and joined by caulking or the like.

On the other hand, the rear end portion of the support pipe 6 is joined to the attachment portion 7 in a state of being inserted into the insertion port 7 a of the attachment portion 7. A wiring connected to the light emitting module 4 is inserted into a hollow portion inside the support pipe 6.
Note that the length of the support pipe 6 is, for example, 30 to 40 cm, the outer diameter is, for example, 27 mm, and the wall thickness is, for example, 1.5 mm to 3 mm.

(Mounting part 7)
As shown in FIGS. 1-3, the attachment part 7 has a function which fixes the rear-end part of the support pipe 6 to construction materials, such as a ceiling. The attachment portion 7 has a truncated cone-shaped external shape whose diameter increases as it goes from the front side to the rear side. An insertion port 7a for receiving the insertion of the support pipe 6 is opened on the front side, and a plurality of holes 7b that allow insertion of screws for fixing to a construction material such as a ceiling are opened in the flange-like portion on the rear side. Yes.

(Outer heat sink 8, inner heat sink 9)
As shown in FIGS. 4 and 5, the inner heat sink 9 is joined to the main surface on the rear side of the module plate 3 around the support pipe 6. The inner heat sink 9 includes a substantially annular support portion 9a that abuts the module plate 3, and a plurality of heat radiation fins 9b that are folded back at the outer peripheral portion of the support portion 9a and extend rearward. Each radiating fin 9b in the inner heat sink 9 has a strip shape elongated in the extending direction.

The outer heat sink 8 also includes a substantially annular support portion 8a that contacts the module plate 3 and a plurality of heat radiation fins 8b that extend rearward. Each of the radiating fins 8b in the outer heat sink 8 has a strip shape elongated in the extending direction.
As shown in FIGS. 4 and 5, the outer heat sink 8 and the inner heat sink 9 are arranged on the inner side of the outer peripheral region where the vent hole 3 c in the module plate 3 is opened. The heat radiating fins 8 b in the outer heat sink 8 are formed in a region that is just inside in the radial direction of the vent hole 3 c provided in the module plate 3. In other words, as shown in FIG. 5, the outer heat sink 8 is arranged so that there is a gap 8 c between adjacent radiating fins 8 b at locations corresponding to the bridges 3 d of the module plate 3.

  Furthermore, as shown in FIG. 5, each radiating fin 8b in the outer heat sink 8 and each radiating fin 9b in the inner heat sink 9 are arranged radially from the center of the module plate 3 (the center of the support pipe 6 and the cylindrical axis of the case 2). It arrange | positions so that it may cross | intersect diagonally with respect to each drawn virtual straight line. Specifically, the heat radiating fins 8b and 9b are disposed so as to intersect with the virtual straight line at an angle (for example, 45 °) within a range of 40 ° to 80 °.

In the inner heat sink 9, gaps 9 c are provided between the adjacent heat radiation fins 9 b, and the number of heat radiation fins 9 b formed is the same as the number of heat radiation fins 8 b formed on the outer heat sink 8.
In the present embodiment, the outer heat sink 8 and the inner heat sink 9 are formed using a material having high thermal conductivity (for example, a metal such as aluminum or an alloy thereof) including the radiation fins 8b and 9b.

(Effects of the lighting device 1)
In the lighting device 1 according to the present embodiment, an outer heat sink 8 and an inner heat sink 9 are provided on the rear main surface of the module plate 3. As a result, the outer heat sink 8 and the inner heat sink 9 are thermally coupled to the light emitting module 4 via the module plate 3. The heat radiation fins 8b in the outer heat sink 8 and the heat radiation fins 9b in the inner heat sink 9 have respective main surfaces with respect to the radial direction of the module plate 3 in a cross section perpendicular to the extending direction of the support pipe 6. It is arranged in an oblique direction.

  Further, gaps 8c and 9c are provided between the adjacent radiating fins 8b and between the adjacent radiating fins 9bn, and the gaps 8c and 9c are formed in the air vent 3c opened in the module plate 3. It will be the position that matches. Therefore, as shown in FIG. 6, in the lighting device 1, the heat generated in the light emitting module 4 during the light emission driving is mainly transmitted to the outer heat sink 8 and the inner heat sink 9 in the case 2, and is transmitted. It is discharged to the outside by the air (Flow1, Flow2) inserted through the air holes 3c and the air holes 2c.

As shown by the arrows in FIG. 6, the heat radiation fins 8 b and 9 b of the outer heat sink 8 and the inner heat sink 9 are arranged obliquely, so that the air flow is improved and heat is efficiently radiated. Further, by disposing the radiating fins 8b and 9c obliquely, an increase in size of the device can be suppressed and high space efficiency can be realized.
(Angle of heat radiation fins 8b and 9b and heat radiation characteristics)
The relationship between the arrangement angle (crossing angle) of the radiation fins 8b and 9c and the radiation characteristics will be described with reference to FIGS. In the following, the heat radiation fin 8b of the outer heat sink 8 is taken as an example for confirmation.

As shown in FIG. 7A, one radiating fin 8b having a width W and a height H was used. Here, the width W = 24 mm and the height H = 40 mm. Moreover, the radiation fin 8b was formed using an aluminum plate having a plate thickness of 1.5 mm.
Next, as shown in FIG. 7B, when a virtual straight line L ₁ passing through the center Ax ₃ of the module plate 3 and the center in the width direction of the radiation fin 8b is drawn, the virtual straight line L ₁ and the radiation fin 8b The fin angle (intersection angle) formed by the main surface is defined as θ. In the confirmation experiment, the heat release was measured by changing the fin angle θ to 10 °, 20 °, 30 °, 40 °, 45 °, 50 °, 60 °, 70 °, 80 °, and 90 °. And the relative value with respect to the emitted-heat amount in case fin angle (theta) = 45 degrees is shown in FIG.

In FIG. 8, the horizontal axis represents the angle θ of the heat radiating fin 8b, and the vertical axis represents the relative value of the heat radiation amount. From FIG. 8, the fin heat dissipation amount Q and the fin angle θ satisfy the following relationship.
[Formula 1] Q = f ₁ (θ ^0.25 )
FIG. 8 shows that the smaller the fin angle θ, the greater the heat radiation. In other words, along main surface to the virtual straight line L ₁ shown in FIG. 7 (b), it is arranged radiating fins 8b preferably it can be seen from the viewpoint of heat dissipation.

(Angle and number of radiating fins 8b and 9b)
As described above, in the present embodiment, each of the outer heat sink 8 and the inner heat sink 9 cuts and raises the outer periphery of a single plate to form a plurality of heat radiation fins 8b and 9b. For this reason, when the outer size of the outer heat sink 8 and the inner heat sink 9 is determined, the number of the radiation fins 8b and 9b that can be formed on the outer periphery is defined by the angle θ of the radiation fins 8b and 9b.

As shown in FIG. 9, the fin angle is θ, and the width of the main surface of the heat radiating fin 8b is W ₀ . At this time, W ₁ , W ₂ , W ₃ , and R can be expressed as follows [Equation 2] W ₁ = W ₀ sin θ
[Formula 3] R = W ₀ cos θ
[Expression 4] W ₂ = R / tan θ
[Expression 5] W ₃ = W ₁ + W ₂
Then, the following equation is obtained by substituting (Equation 2) to (Equation 4) into (Equation 5).
[Formula 6] W ₃ = W ₀ / sin θ
Further, regarding the number N of heat dissipating fins 8b that can be formed on the premise of cutting and raising on an outer periphery of a certain arbitrary length, if it is approximated that the heat dissipating fins 8b are arranged on a straight line, the relationship expressed by the following equation is shown. Can do.
[Expression 7] N = 1 / W ₃
That is, substituting (Equation 6) into (Equation 7) satisfies the relationship of the following equation.
[Equation 8] N = f ₂ (sin θ)
FIG. 10 shows a relative value based on the number of fins when the fin angle θ = 45 °.

As shown in FIG. 10, the relative value of the number N of fins changes in proportion to the fin angle θ. When the fin angle θ = 0 °, the value obtained by dividing the outer circumference length by the height H of the heat dissipating fin 8b is the actual number N of sheets formed. When the fin angle θ = 90 °, the outer circumference length is radiated. The value divided by the width W of the fin 8b is the actual number N of sheets formed.
(The amount of heat released from the fins when the number of fins N is taken into account)
FIG. 11 shows the result of multiplying the relative values at the fin angles θ of FIG. 8 and FIG.

As shown in FIG. 11, the relative value when the fin angle θ = 45 ° is set to “1.000” is a curve having a peak at the fin angle θ = 60 °. And it turns out that a heat dissipation characteristic becomes high in the range whose fin angle (theta) is 40 degrees or more and 80 degrees or less.
In the present embodiment, the fin angle θ of the radiating fin 8b in the outer heat sink 8 and the radiating fin 9b in the inner heat sink 9 is 45 ° as an example. Can be obtained. In particular, it is also preferable that the relative value exceeds “1.000” at 45 ° or more and 80 ° or less and the range is 55 ° or more and 70 ° or less.

[Modification]
In the lighting device 1 according to the above embodiment, two heat sinks (the outer heat sink 8 and the inner heat sink 9) are provided inside the case 2, but the number of heat sinks arranged inside the case 2 is as follows. The number may be one, or three or more. In addition, as shown in FIG. 4 and the like, the lighting device 1 employs a configuration in which the height of the radiating fins 8b in the outer heat sink 8 is lower than the height of the radiating fins 9b in the inner heat sink 9. The height of the fin can be appropriately defined in consideration of the shape of the case 2 and the amount of heat released from the heat sink.

  Further, as shown in FIG. 4 and the like, in the lighting device 1, the number of the radiating fins 8b in the outer heat sink 8 and the number of the radiating fins 9b in the inner heat sink 9 are the same. The number of components may be changed. For example, the number of radiating fins in the outer heat sink may be larger than the number of radiating fins in the inner heat sink, or vice versa.

  Moreover, in the illuminating device 1 which concerns on the said embodiment, although it was set as flat form about the radiation fins 8b and 9b in each heat sink 8 and 9, this invention is not limited to this. For example, when assuming an axial core that passes through the center in the width direction of the radiating fin and passes in the height direction, it is also possible to adopt a radiating fin having a shape rotated around the axis from the lower part to the upper part in the height direction. it can. In this case, the above-mentioned effect can be obtained by setting the fin angle θ as the arrangement angle (intersection angle) of the root portion on the module plate 3 side.

  Moreover, in the illuminating device 1 which concerns on the said embodiment, about each radiation fin 8b, 9b of the outer heat sink 8 and the inner heat sink 9, it was made the rectangular shape whose width | variety is the same in a height direction, but this invention is based on this. It is not limited. For example, a trapezoidal or triangular radiating fin can be used in which the width of the main surface decreases from the root portion on the module plate 3 side to the upper portion in the height direction.

  Moreover, in the illuminating device 1 which concerns on the said embodiment, with respect to the position of the vent hole 3c opened in the module plate 3, the form and arrangement | positioning of the outer heat sink 8 are arrange | positioned so that the position of the clearance gap 8c between the radiation fins 8b may correspond. Although defined, the present invention is not limited to this. For example, from the configuration shown in FIG. 5, the outer heat sink 8 may be rotated by a half pitch of the vent holes 3 c of the module plate 3.

  Moreover, in the illuminating device 1 which concerns on the said embodiment, although the radiation fin 9b of the inner heat sink 9 was spaced apart with respect to the support pipe 6, this invention is not limited to this. For example, at least a part of the heat radiation fins 9b of the inner heat sink 9 may be in contact with or fixed to the outer peripheral portion of the support pipe 6 to adopt a thermally coupled form. Thereby, a part of the heat of the heat radiating fins 9 b can be released to the support pipe 6, and the heat radiation characteristics can be improved.

Moreover, in the illuminating device 1 which concerns on the said embodiment, although the structure provided with the light emitting module 4 by which COB type LED is mounted was employ | adopted, this invention is not limited to this. For example, a light emitting module on which an SMD (surface mount) type LED is mounted may be employed.
Moreover, in the illuminating device 1 which concerns on the said embodiment, although LED was employ | adopted as an example of a semiconductor light-emitting device, this invention is not limited to this. For example, an LD (laser diode), an EL element, or the like can be employed as the semiconductor light emitting element. Moreover, although the number of light emitting modules in the lighting device is six as an example in the lighting device 1 according to the above-described embodiment, the present invention is not limited to this. For example, it may be configured to include one or two to five light emitting modules, or may be configured to include seven or more light emitting modules.

  Moreover, in the illuminating device 1 which concerns on the said embodiment, metal materials, such as aluminum or its alloy, in order to thermally radiate the heat | fever of the light emitting module 4 about the module plate 3, the support pipe 6, the case 2, etc. efficiently. However, the present invention is not limited to this. A resin material or the like can be used as long as it is allowed in relation to the amount of heat dissipation.

  Moreover, in the illuminating device 1 which concerns on the said embodiment, although the support pipe 6 was made into the straight tubular pipe, this invention is not limited to this. For example, the support pipe can be bent in the middle, or a ball joint can be inserted in an intermediate portion in the length direction to adjust the light irradiation direction. It is also possible to adopt a flexible pipe or the like.

[Summary of Embodiments of the Present Invention]
An illumination device according to an aspect of the present invention includes a semiconductor light emitting element, a base, a heat sink, and a case.
The base has a plate shape, and a semiconductor light emitting element is arranged on one surface. The heat sink is arranged on the other surface of the base. The semiconductor light emitting element and the heat sink are in a state of being thermally coupled with the base sandwiched in the thickness direction. The case has a cylindrical shape, and one opening is sealed by the base in a state where the heat sink is housed inside the cylinder.

  In the lighting device according to one embodiment of the present invention, each of the case and the base is provided with a vent hole communicating with the inner space of the case in which the heat sink is accommodated. In addition, the heat sink has a plurality of fins that are erected with respect to the other surface of the base and are disposed so as to surround the cylindrical shaft of the case. Each of the plurality of fins has, in a cross section orthogonal to the cylindrical axis of the case, at least a base portion on the base side with respect to a virtual straight line passing through the cylindrical axis and the center in the width direction of the fin. Are arranged to cross diagonally.

In the illumination device according to the above aspect, the case and the base are provided with vent holes. For this reason, outside air distribute | circulates with respect to the heat sink accommodated in the inner space of the case. Therefore, heat generated in the semiconductor light emitting element is radiated with high efficiency through the heat sink.
Moreover, in the illuminating device which concerns on the said aspect, the external air introduce | transduced from the ventilation hole of the said case and a base passes the clearance gap between the adjacent fins in a heat sink. Thereby, the heat transmitted to the plurality of fins is released to the outside air that passes. Therefore, also by this, in the illuminating device which concerns on this aspect, heat dissipation is made | formed efficiently.

  Moreover, in the illuminating device which concerns on the said aspect, in each of several fin, it arrange | positions so that the base part by the side of each main surface of each main surface may cross | intersect the said virtual straight line in the diagonal direction. Thereby, by the arrangement | positioning of the said fin, the occupation area for arrangement | positioning of a fin can be restrained small rather than the case where the main surface of a fin is distribute | arranged to the direction along a virtual straight line. Further, the number of fins arranged with the same circumference can be increased as compared with the case where the main surfaces of the fins are arranged in a direction orthogonal to the virtual straight line. Therefore, in the illuminating device which concerns on this aspect, while being able to thermally radiate with high efficiency, space efficiency can be made high.

As mentioned above, in the illuminating device which concerns on the said aspect, while being able to thermally radiate the heat which arises with a semiconductor light-emitting element with high efficiency, the enlargement can be suppressed.
Further, in the lighting device according to one aspect of the present invention, the amount of heat released from each of the light-emitting elements during light emission driving is Q, and the crossing angle of each fin with respect to the virtual straight line is θ. Then, based on the relationship of Q = f ₁ (θ ^0.25 ), the intersection angle θ is defined. Thus, by defining the arrangement angle (intersection angle) of each fin based on the above relational expression, the heat dissipation efficiency of each fin can be increased.

Further, in the lighting device according to one aspect of the present invention, in the heat sink, the plurality of fins are formed by cutting up the outer peripheral portion of one plate body, and the number of fins formed in the heat sink is N. In addition to the above relational expression, the crossing angle θ is defined based on the relation N = f ₂ (sin θ). Thus, by defining the arrangement angle (intersection angle) θ of each fin, the heat radiation efficiency of the plurality of fins in the heat sink can be increased. Further, even when a plurality of fins are formed by cutting and raising the outer periphery of the plate body, high space efficiency can be realized.

  Further, in the lighting device according to one aspect of the present invention, specifically, the intersection angle θ is defined within a range of 40 ° to 80 °. As a result of investigations by the inventors based on the above relational expression, it has been found that it is desirable that the crossing angle θ be in the above range from the viewpoints of heat radiation efficiency and space efficiency. Note that the intersection angle θ can be set to the same angle for all of the plurality of fins, and the arrangement direction can be aligned. Further, the intersection angle θ can be set to 45 °, for example, in consideration of the ease of manufacture.

  In the lighting device according to one aspect of the present invention, the second heat sink is provided closer to the cylinder shaft than the region where the heat sink is disposed on the other surface of the base. The second heat sink also has a plurality of fins that are erected with respect to the other surface of the base and are disposed so as to surround the cylindrical shaft of the case. The plurality of fins in the second heat sink are also arranged with a gap between adjacent fins. Thus, by providing the 2nd heat sink which has a plurality of fins, improvement in heat dissipation efficiency can be aimed at further.

  In the illumination device according to one aspect of the present invention, each of the plurality of fins in the second heat sink also has an oblique direction in which at least the base portion on the main surface side of the main surface is oblique to the virtual straight line passing through the cylindrical axis of the case. It is arranged to cross. As described above, by disposing the plurality of fins in the second heat sink so as to intersect in the oblique direction as described above, it is possible to improve the heat radiation efficiency as described above. In addition, the same effect can be acquired by prescribing | regulating also about the arrangement angle (intersection angle) of each fin in a 2nd heat sink based on the said relational expression.

1. Illumination device Case 2c. Ventilation hole Module plate 3a. Fitting hole 3c. Vent hole 4. 4. Light emitting module Cover 6. Support pipe 7. Mounting part 8. Outer heat sink 8b. Radiation fin 8c. Gap 9. Inner heat sink 9b. Radiation fin 9c. Gap

Claims (5)

A semiconductor light emitting device;
A plate-like base on which the semiconductor light emitting element is arranged on one surface;
A heat sink disposed on the other surface of the base;
A case having a cylindrical shape, with one opening being sealed by the base, with the heat sink housed inside the cylinder,
With
Each of the case and the base has a vent hole communicating with the inner space of the case in which the heat sink is housed.
The heat sink has a plurality of fins that are erected with respect to the other surface of the base and are disposed so as to surround the cylindrical shaft of the case.
Each of the plurality of fins is at least on the base side of the main surface with respect to a virtual straight line passing through the cylinder axis and the center in the width direction of the fin in a cross section orthogonal to the cylinder axis of the case. It is arranged so that the root part of
Of the amount of heat generated from the light emitting element during light emission driving, Q is the heat radiation relative value from each fin, and θ is the angle at which the root of the main surface of each fin intersects the virtual straight line.
Q = 1.09 when θ = 10 °, Q = 1.07 when θ = 20 °, Q = 1.05 when θ = 30 °, Q = 1.02 when θ = 40 °, 45 ° When Q = 1, θ = 50 °, Q = 0.98, θ = 60 °, Q = 0.92, θ = 70 °, Q = 0.83, θ = 80 °, Q = The illumination device is characterized in that the angle θ is defined based on all the relationships of 0.7. In the heat sink, the plurality of fins are formed by cutting and raising the outer periphery of a single plate,
When the relative value of the number of fins in the heat sink is N,
In addition to the relationship between Q and θ,
N = 0.25 when θ = 10 °, N = 0.49 when θ = 20 °, N = 0.7 when θ = 30 °, N = 0.91 when θ = 40 °, θ = N = 1 at 45 °, N = 1.09 at θ = 50 °, N = 1.23 at θ = 60 °, N = 1.33 at θ = 70 °, θ = 80 ° The lighting device according to claim 1, wherein the angle θ is defined based on all relationships of N = 1.4. The said angle (theta) is prescribed | regulated in the range of 40 degrees or more and 80 degrees or less. The illuminating device of Claim 1 or Claim 2 characterized by the above-mentioned. A second heat sink is provided on the cylindrical shaft side of the area on the other surface of the base where the heat sink is disposed,
The second heat sink also has a plurality of fins that are erected with respect to the other surface of the base and are arranged so as to surround the cylindrical shaft of the case,
The lighting device according to any one of claims 1 to 3, wherein the plurality of fins in the second heat sink are also arranged with a gap between adjacent fins. Each of the plurality of fins in the second heat sink is also arranged so that at least a base portion on the base side in the main surface intersects in an oblique direction with respect to an imaginary straight line passing through the cylindrical axis of the case. The lighting device according to claim 4, wherein

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