JP6648499B2 - Light source device - Google Patents

Description

  The present invention relates to a light source device.

  2. Description of the Related Art A photocurable material that cures when irradiated with light is known. The photo-curing material has advantages such as curing in a short time, being curable without increasing the temperature of an irradiation target, and being environmentally friendly. Therefore, the photocurable material is used for various applications such as adhesion of electronic components and optical components, and printing technology using the photocurable material as printing ink.

  Also, an exposure technique for performing fine processing using light is known. The exposure technology is used, for example, for manufacturing an electrode pattern of an LED, a manufacturing process of MEMS (Micro Electro Mechanical Systems) represented by an acceleration sensor, and the like.

  In these techniques, a discharge lamp having a high luminance has been used as a light source before. However, with the progress of the solid-state light source technology in recent years, it has been studied to use, as a light source, a light source in which a plurality of solid-state light source elements are arranged instead of a discharge lamp (for example, see Patent Documents 1 and 2 below). .

  FIG. 7 shows a light source device 100 in Patent Document 1. The light source device 100 has six light emitting units (103, 104, 105, 106, 107, 108) arranged in two rows and three columns. Each light emitting unit is composed of eight LED elements 109 connected in series. The eight LED elements 109 connected in series are connected to one connector 110. Each light emitting unit is electrically connected in parallel by a connector 110. The substrate 112 is fixed to the upper surface of a heat sink (not shown) by screws 113.

  Although not shown, the light source device in Patent Document 2 includes a plurality of LED elements and a substrate. The board is provided with an input connector and an output connector. The LED element is connected to a power supply by the connector. Further, the substrate is fixed to the upper surface of the heat sink by a fixing screw (see FIG. 6 of Patent Document 2).

  As shown in the above two documents, in the related art, mechanical fixing of a substrate and a heat sink is realized by using a fixing member such as a fixing screw, and a light emitting element (LED element) and a power supply are realized by using a connector. Electrical connection is realized.

JP 2011-103261 A JP 2005-352427 A

  In recent years, in order to achieve high illuminance of a light source device, it is required to arrange a large number of light emitting elements in a light source.

  However, as described above, in the conventional technology, mechanical fixing of the substrate is realized by a fixing member such as a fixing screw, and power supply to the light emitting element is realized by the connector. The two members are formed in different regions on the substrate. That is, in the conventional technique, it is necessary to separately provide a region for disposing the fixing member and a region for disposing the connector on the substrate, and there is a problem that a large number of light emitting elements cannot be disposed on the substrate.

  Therefore, the present inventor has studied a configuration in which mechanical fixing of the substrate and power supply to the light emitting element are realized in the same region on the substrate in order to enlarge the arrangement region of the light emitting element. Specifically, a configuration in which both the mechanical fixing of the substrate and the power supply to the light emitting element are realized using a fixing member such as a fixing screw without using a connector was studied.

  However, according to the inventor's earnest research, when the above-described configuration is employed, a device that emits no light at all partially occurs, or a light-emitting device that switches between lighting and non-lighting irregularly occurs. It was found that a problem that light emission could not be realized occurred.

  An object of the present invention is to provide a technology capable of realizing high-density mounting of a light emitting element and realizing stable light emission of the element.

The light source device of the present invention
Board and
A plurality of light emitting elements mounted on the main surface of the substrate,
A wiring pattern mounted on the main surface of the substrate and electrically connecting a plurality of the light emitting elements;
A heat conductive material provided on the back surface of the substrate,
A heat sink provided on the opposite side of the heat conductive material from the substrate;
A power supply terminal provided on the wiring pattern of the substrate,
An elastic member that is in contact with the power supply terminal directly or via another member and that can expand and contract in a direction perpendicular to the main surface of the substrate,
Having a fixing member for fixing the substrate and the heat sink,
An end of the elastic member opposite to the power supply terminal is in contact with an end of the fixing member opposite to the heat sink.

  According to the above configuration, one end of the elastic member contacts the fixing member, and the other end contacts the power supply terminal directly or via another member. That is, the fixing member fixes the substrate and the heat sink, and also fixes the power supply terminal and the substrate via the elastic member. Accordingly, both the mechanical fixing of the substrate and the power supply to the light emitting element can be realized in the same region, so that high density mounting of the light emitting element can be realized.

  The fixing member fixes the power supply terminal and the substrate by pressing the elastic member. Accordingly, a force for pressing each other acts between the power supply terminal and the substrate, so that poor contact between the power supply terminal and the substrate can be improved. That is, stable light emission of the element can be realized.

In the above configuration,
The elastic member may be contracted from a natural state where no external force acts.

  According to the above configuration, an elastic force for restoring a natural state acts on the elastic member, so that a pressing force acts between the power supply terminal and the substrate. As a result, poor contact between the power supply terminal and the substrate can be improved, and stable light emission of the element can be realized.

In the above configuration,
The fixing member includes a head and a shaft extending from the head and having a smaller diameter than the head,
The substrate and the heat sink include a fixing hole into which the shaft of the fixing member is inserted,
Of the shaft portion, a part of the region including the end opposite to the head is inserted into the fixing hole of the substrate and the heat sink,
An end of the elastic member opposite to the power supply terminal may be in contact with the head of the fixing member.

In the above configuration,
An insulating material covering a part of the outer periphery of the shaft portion of the fixing member,
The power supply terminal may be in contact with the fixing member via the insulating material.

  According to the above configuration, the power supply terminal contacts the fixing member via the insulating material. That is, the power supply terminal does not directly contact the fixing member. Accordingly, it is possible to suppress occurrence of discharge between the power supply terminal and the fixing member.

In the above configuration,
Having a washer on the upper surface of the insulating material,
An end of the elastic member opposite to the fixing member may be in contact with the washer.

  According to the above configuration, since the elastic member contacts the insulating material via the washer, it is possible to suppress the elastic member from sinking into the insulating material. Thereby, it can suppress that an insulating material hinders expansion-contraction of an elastic member.

In the above configuration,
The elastic member may be a disc spring.

  According to the above configuration, the fixing member fixes the power supply terminal and the substrate by pressing the disc spring. As a result, an elastic force that attempts to restore the natural state acts on the disc spring, so that a pressing force acts between the power supply terminal and the substrate. As a result, poor contact between the power supply terminal and the substrate can be improved, and stable light emission of the element can be realized.

  ADVANTAGE OF THE INVENTION According to the light source device of this invention, while implementing high-density mounting of a light emitting element, it can implement | achieve stable light emission of an element.

It is a figure showing typically composition of one embodiment of a light source device of the present invention. FIG. 3 is a schematic diagram for explaining a light emitting unit included in the light source device of the embodiment. It is a mimetic diagram for explaining a wiring pattern formed in a substrate with which a light source device of an embodiment is provided. FIG. 3 is a schematic sectional view taken along line BB in FIG. 2. FIG. 4 is a schematic diagram for explaining the operation and effect of the light source device of the embodiment. It is a figure which shows the structure of the light source device of another embodiment typically. FIG. 3 is a diagram schematically illustrating a configuration of a light source device according to a related art.

  The light source device according to the present embodiment will be described with reference to the drawings. Hereinafter, a light source device used as a light source of a printing device or an exposure device will be described as an example. In each of the drawings, the dimensional ratio in the drawings does not always match the actual dimensional ratio.

[Configuration of light source device]
The configuration of the light source device 1 according to the present embodiment will be described. FIG. 1A is a schematic plan view of the light source device 1, and FIG. 1B is a schematic cross-sectional view of the light source device 1 taken along line AA.

  As shown in FIGS. 1A and 1B, the light source device 1 includes a light emitting unit 4, a heat sink 5, and a water cooling block 7. In the present embodiment, as an example, the light emitting unit 4 of the light source device 1 is configured by five light emitting units (41, 43, 45, 47, 49).

  In FIG. 1, the direction in which the five light emitting units (41, 43, 45, 47, 49) are arranged, that is, the longitudinal direction of the light source device 1 is defined as the x direction, the short direction of the light source device 1 is defined as the y direction, and x The direction orthogonal to the direction and the y direction is defined as the z direction.

  The light emitting units (41, 49) include three substrates 8 arranged side by side in the x direction. The light emitting units (43, 45, 47) include two substrates 8 arranged side by side in the x direction. Thus, the light emitting section 4 includes twelve substrates 8. As an example, the substrate 8 is made of AlN (ceramic).

  A number of LED elements (not shown) are arranged on each substrate 8. In FIG. 1, the area where the LED elements are arranged is indicated by a rectangle 9 for convenience. For example, an LED element that emits ultraviolet light having a wavelength of 365 nm is disposed on the substrate 8 of the light emitting units (41, 45, 49), and the substrate 8 of the light emitting units (43, 47) is, for example, 405 nm. An LED element that emits ultraviolet light having a wavelength is arranged.

  In the present embodiment, the light emitting units (41, 43, 45, 47, 49) are connected to different power supplies. The light emitting units (41, 43, 45, 47, 49) may share one or a plurality of power supplies.

  The details of the light emitting section 4 will be described later.

  A heat conductive sheet 37 is provided on the upper surface of the heat sink 5 (see FIG. 1B). The substrate 8 of the light emitting section 4 is attached to the heat sink 5 via the heat conductive sheet 37. The heat conductive sheet 37 is made of a material having a high heat conductivity, and enhances the adhesion between the heat sink 5 and the substrate 8. More specifically, the heat conductive sheet 37 softens due to a rise in temperature of the light emitting unit 4 due to light emission, thereby bringing the heat sink 5 and the substrate 8 into close contact with each other. The heat conductive sheet 37 efficiently conducts heat generated when the light emitting unit 4 emits light to the heat sink 5. The heat conductive sheet 37 is formed of, for example, a silicone resin or an acrylic resin. Note that the heat conductive sheet 37 corresponds to a “heat conductive material”.

  The heat sink 5 conducts heat from the heat conductive sheet 37 to the water cooling block 7. As an example, the heat sink 5 is made of Cu (copper). In the present embodiment, the light emitting units (41, 43, 45, 47, 49) include the same number of heat sinks 5 as the substrate 8. Note that a configuration in which a plurality of substrates 8 are mounted on one heat sink 5 may be employed.

  A heat sink 5 is attached to the upper surface of the water cooling block 7 (see FIG. 1B). The water cooling block 7 discharges heat from the heat sink 5 to the outside of the light source device 1. More specifically, the cooling water flows from one pipe joint 11 and circulates through the water-cooling block 7 to the other pipe joint 13 to cool the light emitting unit 4.

[Configuration of Light Emitting Unit]
Next, the light emitting unit 4 will be described. As an example, the light emitting unit 43 will be described with reference to FIG. The other light-emitting units (41, 45, 47, 49) have the same configuration, and a description thereof will be omitted. FIG. 2 shows a state in which the light emitting unit 43 is fixed on the heat sink 5 for convenience of explanation.

  As described above, the light emitting unit 43 includes the two substrates (81, 83) arranged in the x direction. Note that the substrates (81, 83) and the like in FIG. 2 are collectively referred to as “substrate 8” in FIG. The light emitting section 43 includes an LED element 15, a wiring pattern 17, and a Zener diode 19 on two substrates (81, 83). The upper surface of the substrate (81, 83) (the surface opposite to the heat sink 5 and the surface on the z direction side in the drawing, the same applies hereinafter) corresponds to the "main surface", and the lower surface (the surface on the heat sink 5 side). And a surface on the −z direction side in the drawing, the same applies hereinafter) corresponds to the “back surface”.

  The LED elements 15 are arranged in large numbers on the substrates (81, 83). In the present embodiment, as an example, 160 LED elements 15 are arranged on each substrate (81, 83). In each substrate (81, 83), ten LED elements 15 are arranged in the y direction and sixteen in the x direction. Note that the ten LED elements 15 arranged in the y direction are arranged such that the coordinates in the y direction deviate from the ten adjacent LED elements 15. Note that the LED element 15 corresponds to a “light emitting element”.

  The wiring pattern 17 is, for example, a metal wiring formed on the upper surface of the substrate (81, 83) using a metal material such as Cu (copper). The wiring pattern 17 electrically connects the LED elements 15. FIG. 3 shows the wiring pattern 17 in the light emitting section 43.

  As shown in FIG. 3, the wiring pattern 17 includes an arrangement area 25 and four power supply areas 27. The arrangement area 25 is an area where the LED elements 15 are arranged. On each of the substrates (81, 83), 16 rows of metal wirings extending in the y direction are formed, and the wiring area 25 is formed of 32 rows of metal wirings. Ten LED elements 15 are arranged in each column of the arrangement area 25. The power supply region 27 is a region that contacts a power supply terminal described later, and is a region for receiving power from a power supply (not shown). As an example, the power supply region 27 on the substrate 81 is connected to the anode side of the power supply, that is, the high potential side, and the power supply region 27 on the substrate 83 is connected to the cathode side of the power supply, that is, the low potential side.

  Returning to FIG. 2, the description will be continued. In each substrate (81, 83), ten LED elements 15 arranged in a line in the y direction are connected to wiring patterns 17 adjacent in the -x direction by wires (not shown). That is, the 16 LED elements arranged in the x direction are electrically connected in series. The substrates (81, 83) are connected by a conductive connecting member 21. The connecting member 21 is in contact with the wiring pattern 17 of the substrate (81, 83). That is, the 32 LED elements arranged in the x direction form a series circuit. Further, in this embodiment, ten series circuits are connected in parallel.

  The Zener diode 19 is an element for protecting the LED element 15 from overvoltage or static electricity. The Zener diode 19 is connected in parallel to a series circuit composed of 32 LED elements 15 arranged in the x direction. Note that the light emitting section 43 does not have to include the Zener diode 19.

  Subsequently, fixing of the light emitting unit 43 and the heat sink 5 will be described. As shown in FIG. 2, the light emitting section 43 includes a fixing screw 29, a power supply terminal 32, an insulating bush 33, and a washer 35. Further, the light emitting section 43 includes a disc spring (not shown). The fixing screw 29 fixes the heat sink 5, the substrate (81, 83), the power supply terminal 32, the insulating bush 33, the washer 35, and a disc spring (not shown). Hereinafter, a specific description will be given with reference to FIG.

[Fixed with fixing screw]
FIG. 4A is a schematic cross-sectional view taken along line BB in FIG. FIG. 4B is a cross-sectional view of FIG. 4A, in which only the heat sink 5 and the substrate 8 are shown and other members are not shown.

  As shown in FIG. 4A, the fixing screw 29 includes a head 30 and a shaft 31. The shaft portion 31 extends from the head portion 30 and has a diameter d2 smaller than the diameter d1 of the head portion 30. The shaft portion 31 has a groove (not shown).

  A fixing hole 51 into which the shaft portion 31 of the fixing screw 29 is inserted is formed in the heat sink 5 (see FIG. 4B). The fixing hole 51 is formed to fit into the groove of the shaft portion 31 of the fixing screw 29. Note that the fixing hole 51 may be formed by a notch. The fixing screw 29 corresponds to a “fixing member”.

  A heat conductive sheet 37 is provided on the upper surface of the heat sink 5.

  The substrate 8 is provided on the upper surface of the heat conductive sheet 37. Similar to the heat sink 5, the substrate 8 has a fixing hole 53 into which the shaft 31 of the fixing screw 29 is inserted (see FIG. 4B). Note that the fixing hole 53 may be formed by a notch. The substrate 8 is arranged such that the fixing holes 53 overlap the upper portions of the fixing holes 51 of the heat sink 5.

  A power supply terminal 32 is arranged on the power supply area 27 on the substrate 8. Although not shown, the power supply terminal 32 has a fixing hole into which the shaft 31 of the fixing screw 29 is inserted. The fixing holes may be formed by notches. The power supply terminal 32 is arranged so that the fixing hole overlaps the fixing holes (51, 53) of the heat sink 5 and the substrate 8. The power supply terminal 32 is connected to a power supply (not shown) by a wiring (not shown). The power supply terminal 32 electrically connects the power supply and the power supply region 27.

  The insulating bush 33 covers a part of the outer periphery of the shaft 31 of the fixing screw 29. Specifically, the insulating bush 33 covers a region of the shaft portion 31 near the power supply terminal 32. Thus, the insulating bush 33 prevents the power supply terminal 32 from directly contacting the head 30 and the shaft 31 of the fixing screw 29. In other words, the power supply terminal 32 is in contact with the fixing screw 29 via the insulating bush 33. The insulating bush 33 is made of an insulating material such as Teflon (registered trademark), for example. Note that the insulating bush 33 corresponds to the “insulating material”.

  A washer 35 is provided on the upper surface of the insulating bush 33. Although not shown, the washer 35 has a fixing hole into which the shaft 31 of the fixing screw 29 is inserted. The fixing holes may be formed by notches. The washer 35 is disposed such that the fixing hole overlaps the fixing holes (51, 53) of the heat sink 5 and the substrate 8. The washer 35 is made of, for example, an insulating material such as stainless steel.

  A disc spring 39 is provided on the upper surface of the washer 35. The disc spring is a disk having a hole in the center formed in a conical shape. By pressing the disc in the direction of the central axis (that is, in the -z direction in FIG. 4), it is possible to restore a natural state in which no external force is applied. This spring generates an elastic force. The disc spring 39 is arranged such that the above-mentioned hole at the center overlaps the fixing holes (51, 53) of the heat sink 5 and the substrate 8. The disc spring 39 corresponds to an “elastic member”.

  As described above, the heat sink 5, the substrate 8, the power supply terminal 32, the insulating bush 33, the washer 35, and the disc spring 39 have the fixing holes into which the shaft 31 of the fixing screw 29 is inserted. The fixing screw 29 fixes each member by being tightened with a predetermined torque in a state where the shaft portion 31 is inserted into the fixing hole. Thus, according to the light source device 1 of the present embodiment, the fixing screw 29 fixes the heat sink 5 and the substrate 8 and also fixes the substrate 8 and the power supply terminal 32. Thereby, both the mechanical fixing of the substrate 8 and the power supply to the LED elements 15 can be realized in the same area, and a large number of LED elements 15 can be arranged on the substrate 8.

  The disc spring 39 shown in FIG. 4 is pressed in the −z direction by the fixing screw 29 and is in a contracted state from a natural state. Therefore, an elastic force acting to restore the natural state is applied to the disc spring 39. That is, a force that pushes back the head 30 of the fixing screw 29 in the z direction acts on the disc spring 39 and a force that pushes the washer 35 in the −z direction acts.

  As described above, a pressing force acts between the fixing screw 29 and the disc spring 39. Similarly, between the disc spring 39 and the washer 35, between the washer 35 and the insulating bush 33, between the insulating bush 33 and the power supply terminal 32, between the power supply terminal 32 and the substrate 8, and between the substrate 8 and the heat sink 5. Forces that push each other act.

[Effects]
Next, the operation and effect of the light source device 1 of the embodiment will be described. First, the configuration of the light source device of the reference example and the problems that occur in the light source device of the reference example will be described.

  Although not shown, the light source device of the reference example is different from the light source device 1 of the embodiment only in that the light source device does not include the washer 35 and the disc spring 39, and other configurations are the same. The inventor of the present invention has found that, when the power supply to the light source device of the reference example is continued for a certain period of time, an LED element 15 that does not emit light at all partially occurs, or a light-emitting element that switches between lighting and non-lighting irregularly occurs. It has been confirmed that a problem arises in that the device cannot emit light. That is, in the light source device of the reference example, it was found that a sudden decrease in illuminance and a decrease in illuminance uniformity occurred. The present inventor considers the reason why stable light emission of the LED element 15 cannot be realized in the light source device of the reference example as follows.

  In the light source device of the reference example, it was confirmed that when power supply was continued for a certain period of time, the thickness of the heat conductive sheet (see FIG. 4A) interposed between the heat sink and the substrate was reduced. As described above, the heat conductive sheet softens due to a rise in the temperature of the light emitting portion due to light emission. Here, in the light source device of the comparative example, a large number of LED elements (for example, 160) are arranged on one substrate. Therefore, it takes time for the temperature of the light emitting portion to become relatively high and to decrease to a temperature at which the softened heat conductive sheet hardens. Therefore, it is considered that the heat conductive sheet was extruded by the fastening of the fixing screw before being cured, and as a result, the thickness of the heat conductive sheet was reduced. In addition, as an example, the temperature at which the heat conductive sheet softens is 50 ° C., and the operating temperature of the light emitting unit during light emission (hereinafter, referred to as “temperature during light emission”) is 85 to 100 ° C.

  Further, in the light source device of the reference example, it was confirmed that the insulation bush was deformed when the power supply was continued for a certain time. It is considered that the insulating bush was pressed by the fixing screw in a state where the insulating bush was heated by the temperature rise of the light emitting unit. As an example, the temperature at which the insulating bush can be used under a load is 50 ° C. or lower, which is lower than the “temperature at the time of light emission” of 85 to 100 ° C.

  As described above, in the light source device of the reference example, when the power supply is continued for a certain period of time, a phenomenon occurs in which the thickness of the heat conductive sheet is reduced and the insulating bush is deformed. The present inventor considered that a gap was formed between the members that were in contact with each other before the power was supplied due to the phenomenon, and that a pressing force between the members did not work. That is, the pressing force does not act between the heat sink, the substrate, the power supply terminal, the insulating bush, and the fixing screw, and a contact failure occurs between the substrate and the power supply terminal. As a result, stable light emission of the LED element 15 is realized. I thought that it was no longer possible.

  In order to solve the above problem, it is expected that a heat conductive sheet that softens at a temperature higher than the “temperature at the time of light emission” (for example, 85 to 100 ° C.) will be adopted. However, as described above, the heat conductive sheet is softened to enhance the adhesion between the heat sink and the substrate. Therefore, when the temperature at which the heat conductive sheet softens is higher than the “temperature at the time of light emission”, the temperature of the light emitting unit is set to “the temperature at the time of light emission” (for example, 85 to 85) in order to soften the heat conductive sheet. (100 ° C.). If the temperature of the light emitting unit rises above the “temperature at the time of light emission”, the LED element 15 may be deteriorated. Therefore, a heat conductive sheet that softens at a temperature higher than the “temperature at the time of light emission” cannot be adopted.

  Therefore, the present inventor has constructed the light source device 1 of the embodiment in view of the above consideration. Then, when the power supply to the light source device 1 of the embodiment was continued for a certain period of time, it was confirmed that stable light emission of the LED element 15 could be realized. That is, according to the light source device 1 of the embodiment, it has been found that the contact failure between the substrate and the power supply terminal can be improved. Hereinafter, the operation and effect of the light source device 1 of the embodiment will be described with reference to FIG.

  FIG. 5 is a schematic cross-sectional view taken along line BB in FIG. Note that FIG. 5A shows a state before power is supplied to the light emitting unit 43, and FIG. 5B shows a state after power supply to the light emitting unit 43 is continued for a certain time. Hereinafter, the state after the power supply has been continued for a certain period of time is referred to as “after power supply”.

  As shown in FIG. 5, the thickness of the heat conductive sheet 37 and the insulating bush 33 after the power supply (FIG. 5B) is smaller than before the power supply (FIG. 5A). Therefore, the distance from the lower surface of the heat sink 5 to the upper surface of the washer 35 is smaller after power supply (d4 in FIG. 5B) than before power supply (d3 in FIG. 5A). In this specification, the length in the z direction is expressed as “thickness”.

  Here, the light source device 1 of the embodiment includes a disc spring 39 between the head 30 of the fixing screw 29 and the washer 35. As described above, the disc spring 39 is pressed in the −z direction by the fixing screw 29, so that an elastic force for restoring a natural state is applied. Therefore, even if the thickness of the heat conductive sheet 37 or the insulating bush 33 is reduced due to a rise in the temperature of the light emitting section 43, the disc spring 39 is restored toward the natural state by the reduced amount (see FIG. 5B). That is, the length of the disc spring 39 in the z direction is increased by the decrease in the thickness of the heat conductive sheet 37 and the insulating bush 33 (that is, d3-d4). As a result, the heat sink 5 and the board 8, the board 8 and the power supply terminal 32, the power supply terminal 32 and the insulating bush 33, the insulating bush 33 and the washer 35, the washer 35 and the disc spring 39, the disc spring 39 and the fixing screw 29 pass through a space. Without direct contact and can push each other.

  As described above, according to the light source device 1 of the embodiment, the members come into contact with each other before and after the power is supplied, and can press each other. Thereby, poor contact between the substrate 8 and the power supply terminal 32 can be improved, and light emission of the LED element 15 can be stabilized.

  The inventor has determined the disc spring 39 to be used for the light source device 1 in the embodiment as follows. First, the inventor measured the total amount of reduction in the thickness of the heat conductive sheet 37 and the insulating bush 33 in the light source device of the reference example. Then, when the fixing screw 29 was tightened with a predetermined torque, the disc spring 39 contracted more than the total amount from the natural state was selected. That is, the disc spring 39 whose contraction amount of the disc spring> d3-d4 is selected (see FIG. 5).

  As a result, even if the disc spring 39 extends by the reduced thickness of the heat conductive sheet 37 and the insulating bush 33 after the power is supplied, the contracted state of the disc spring 39 compared to the natural state is maintained. That is, even after power is supplied, the disc spring 39 is subjected to an elastic force for restoring a natural state. Therefore, a pressing force acts between the fixing screw 29 and the disc spring 39 and between the disc spring 39 and the washer 35, and similarly, between the washer 35 and the insulating bush 33, between the insulating bush 33 and the power supply terminal 32. A pressing force acts between the power supply terminal 32 and the substrate 8 and also between the substrate 8 and the heat sink 5. As a result, poor contact between the power supply terminal 32 and the substrate 8 can be improved.

  According to the light source device 1 of the embodiment, the power supply terminal 32 does not directly contact the fixing screw 29 but contacts the fixing screw 29 via the insulating bush 33. Thus, it is possible to prevent a discharge from occurring between the power supply terminal 32 and the fixing screw 29, and to prevent a current supplied from the power supply from leaking.

  Further, according to the light source device 1 of the embodiment, the disc spring 39 is provided on the upper surface of the washer 35 without directly contacting the insulating bush 33. Thereby, when the fixing screw 29 is tightened, the disc spring 39 can be prevented from sinking into the insulating bush 33. That is, it is possible to prevent the insulating bush 33 from hindering the contraction and extension of the disc spring 39, and to secure the contraction amount of the disc spring 39.

[Another embodiment]
It should be noted that the light source device is not limited to the configuration of the above-described embodiment, and it is needless to say that various changes can be made without departing from the scope of the present invention. For example, it goes without saying that a configuration according to another embodiment described below may be arbitrarily selected and employed in the configuration according to the above embodiment.

  <1> In the light source device 1 of the embodiment, as shown in FIG. 4, the shaft 31 of the fixing screw 29 penetrates the substrate 8, but is not limited thereto. FIG. 6 shows a schematic cross-sectional view of a light source device 1a according to another embodiment. The light source device 1a of another embodiment is different from the light source device 1 of the embodiment in that a power supply terminal 32a is provided instead of the power supply terminal 32, and that the shaft 31 of the fixing screw 29 does not penetrate the substrate 8. Is the same. Hereinafter, the light source device 1a according to another embodiment will be described focusing on the differences from the light source device 1 according to the embodiment.

  FIG. 6 is a schematic cross-sectional view when the light source device 1a of another embodiment is cut along the short direction (that is, the y direction) of the light source device 1a. As shown in FIG. 6, the substrate 8 is provided on the heat sink 5 via a heat conductive sheet 37. The fixing screw 29 fixes the heat sink 5, the power supply terminal 32a, the insulating bush 33, the washer 35, and the disc spring 39.

  The power supply terminal 32 a is fixed by a fixing screw 29 in a state in which one end is in contact with the power supply region 27 on the substrate 8 and the other end is in contact with the heat sink 5. That is, the fixing screw 29 fixes the substrate 8 via the power supply terminal 32a without directly contacting the substrate 8. Thus, in the light source device 1 a of another embodiment, the shaft 31 of the fixing screw 29 does not penetrate the substrate 8.

  In the light source device 1a according to another embodiment, similarly to the light source device 1 according to the embodiment, when the power supply is continued for a certain period of time, the thickness of the heat conductive sheet 37 and the insulating bush 33 can be reduced. Here, the light source device 1 a of another embodiment includes a disc spring 39 between the head 30 of the fixing screw 29 and the washer 35. Therefore, for the same reason as that of the light source device 1 of the embodiment, between the fixing screw 29 and the disc spring 39, between the disc spring 39 and the washer 35, between the washer 35 and the insulating bush 33, between the insulating bush 33 and the power supply terminal 32a. A pressing force acts between the power supply terminal 32 a and the substrate 8, and also between the substrate 8 and the heat sink 5. As a result, poor contact between the power supply terminal 32a and the substrate 8 can be improved.

  <2> The light source device 1 may use a disc spring washer, a spring washer, a coil spring, a leaf spring, or the like instead of the disc spring 39. That is, an elastic member may be used. The disc spring 39 has an advantage that the resilience when pressed is relatively easily maintained.

  <3> In the embodiment, it has been described that the disc spring 39 is selected to be capable of contracting more than the total amount of the reduction in the thickness of the heat conductive sheet 37 and the reduction in the thickness of the insulating bush 33, but is not limited thereto. Absent. For example, when the insulating bush 33 is excellent in heat resistance, that is, when the temperature at which the insulating bush 33 can be used is higher than the “temperature at the time of light emission” (for example, 85 to 100 ° C.) of the light emitting unit, Even if the power supply is continued, the insulating bush 33 is not deformed. In this case, instead of the disc spring 39, a disc spring that can contract more than the decrease in the thickness of the heat conductive sheet 37 may be selected.

  <4> The light source device 1 includes the heat conductive sheet 37 between the heat sink 5 and the substrate 8, but is not limited to a sheet. For example, the same material as that of the heat conductive sheet 37 may be applied in a dot shape on the upper surface of the heat sink 5.

  <5> The light source device 1 may not include the water-cooling block 7, the insulating bush 33, and the washer 35. In addition, the light emitting unit 4 includes five light emitting units (41, 43, 45, 47, and 49), but the number of light emitting units is not limited thereto. Each of the five light emitting units (41, 43, 45, 47, 49) includes two or three substrates 8, but may be configured by one substrate. Further, the configuration is not limited to the configuration in which the substrate 8 is different for each of the light emitting units (41, 43, 45, 47, 49), and five light emitting units may be formed on one substrate 8. By configuring each light emitting unit with a plurality of substrates 8 as in the light source device 1 of the present embodiment, it is possible to increase the wavelength of the light emitting unit 4 and improve the illuminance distribution. Further, when a certain substrate 8 is damaged or the like, it is possible to repair or replace the substrate.

1: Light source device of embodiment 1a: Light source device of another embodiment 4: Light emitting unit 41, 43, 45, 47, 49: Light emitting unit 5: Heat sink 7: Water cooling block 8: Substrate 81, 83: Substrate 11, 13: Piping joint 15: LED element 17: Wiring pattern 19: Zener diode 21: Connecting member 25: Arrangement area 27: Power supply area 29: Fixing screw 30: Head 31: Shaft part 32: Power supply terminal 32a: Power supply terminal of another embodiment 33: insulating bush 35: washer 37: heat conductive sheet 39: disc spring 51, 53: fixing hole

Claims (5)

Board and
A plurality of light emitting elements mounted on the main surface of the substrate,
A wiring pattern mounted on the main surface of the substrate and electrically connecting a plurality of the light emitting elements;
A heat conductive material provided on the back surface of the substrate,
A heat sink provided on the opposite side of the heat conductive material from the substrate;
A power supply terminal provided on the wiring pattern of the substrate,
An elastic member that is in contact with the power supply terminal directly or via another member and that can expand and contract in a direction perpendicular to the main surface of the substrate,
A fixing member for fixing the substrate and the heat sink , comprising: a head, a shaft extending from the head, and having a smaller diameter than the head ;
An insulating material covering a part of the outer periphery of the shaft portion of the fixing member ,
The elastic member is disposed between the head of the fixing member and the insulating member in the axial direction of the shaft of the fixing member, one end of which contacts the head of the fixing member, and the other end of which is the insulating member. A light source device, which comes into contact with a material directly or via another member .   The light source device according to claim 1, wherein the elastic member is contracted from a natural state where no external force is applied. The feeding terminal has a light source device according to claim 1 or 2, characterized in that contact with the fixing member via the insulating material. Having a washer on the upper surface of the insulating material,
The other end of the elastic member, a light source device according to any one of claims 1 to 3, characterized in that in contact with the insulating material through said washer. The light source device according to claim 1, wherein the elastic member is a disc spring.

Images