JP2013211251A - Light source unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light source unit capable of restraining deflection of optical components.SOLUTION: A light source unit 1 is provided with: a light source substrate 20 with a plurality of ultraviolet LEDs 30 arrayed on a surface; and an irregular-shaped rod lens 6 as an optical component covering the ultraviolet LEDs 30 for controlling light. A pair of support pieces 44 are provided extending at either side of the irregular-shaped rod lens 6 along edges, and a lens holder 24 for supporting the pair of support pieces 44 of the irregular-shaped rod lens 6 and arranged at a position covering the ultraviolet LEDs 30 are provided at the light source substrate 20.

Description

  The present invention relates to a light source unit including a light source such as an LED as a light source, and more particularly to a light source unit suitable for use as a light source for curing a photocurable material.

  2. Description of the Related Art Conventionally, an ink jet recording apparatus that forms an image by ejecting ink that is cured by irradiation with light such as ultraviolet rays onto a recording medium using an ink jet head and curing the ink by light irradiation is known. Such an ink jet recording apparatus is characterized by being friendly to the environment, capable of recording on various recording media at high speed, and obtaining a high-definition image that is difficult to bleed. In such an ink jet recording apparatus, after the ink has landed on the recording medium, the image quality is improved by quickly photocuring the ink. For this purpose, a high output and relatively large light irradiation apparatus is used. It is necessary to prepare. In view of this, a light irradiation device has been proposed in which a plurality of ultraviolet LEDs are arranged in a row on a substrate and an LED unit configured to irradiate ultraviolet rays over a wide range with a high output is provided as a light source (for example, Patent Literature 1).

JP 2010-110938 A

By the way, as the printing surface becomes larger, the arrangement of the LEDs becomes longer. When the array length of the LEDs becomes long, for example, when the light of each LED is controlled by a transmissive optical component such as a rod lens, the total length of the rod lens also becomes long. There is a problem that uniform irradiation cannot be performed.
The present invention has been made in view of the above-described circumstances, and an object of the present invention is to provide a light source unit in which bending of an optical component can be suppressed.

  In order to achieve the above object, the present invention includes a light emitting element substrate having a plurality of light emitting elements arranged on the surface, and an optical component that covers each of the light emitting elements and controls light, and is provided on both sides of the optical component. A pair of support pieces extending along the edge portion is provided on the light emitting element substrate, and the light emitting element substrate is provided with an optical component holder that is disposed at a position that supports the pair of support pieces of the optical component and covers each of the light emitting elements. A light source unit is provided.

  According to the present invention, in the light source unit, the optical component controls the light emitted from the first light control unit and the first light control unit that controls the incident light that is emitted from the light emitting element. The second light control unit has the first light control unit and the second light control unit on each of the front surface and the back surface, and transmits the light from the first light control unit to control the second light control. The support plate that transmits to the part, and the support plate have the pair of support pieces at each end that sandwich the first light control unit and the second light control unit.

  According to the present invention, in the light source unit, the optical component holder is provided with a storage opening that surrounds the light emitting element and accommodates the optical component, and the light emitting element is closed by the optical component. Each of which is sealed.

  According to the present invention, in the light source unit, a cooling means for cooling each of the light emitting elements is provided on the back surface of the light emitting element substrate.

  According to the present invention, in the light source unit, the cooling means is provided with a flow path groove that forms a flow path of a refrigerant between the light emitting element substrate and a back surface of the light emitting element substrate. Each of the light emitting elements is cooled through a substrate.

  According to the present invention, in the light source unit, the cooling means is provided with a flow channel groove that forms a flow channel for a coolant, and the light source is cooled through the light emitting device substrate by the coolant flowing in the flow channel. It is characterized by that.

  Further, in the light source unit according to the present invention, the cooling unit includes the flow channel groove formed on a surface, and is screwed so that another member is in contact with the surface. The other member and the flow channel groove Provided with a cooling base body that constitutes the flow path, the surface of the cooling base body is provided with a space for forming screw holes for screwing at opposite edges, and the flow path groove is formed in the remaining space. Is provided.

  According to the present invention, there is provided an optical component holder that is provided with a pair of support pieces extending along the edge on both sides of the optical component, and is disposed at a position that covers each of the light emitting elements by supporting the pair of support pieces of the optical component. It was set as the structure equipped with a light emitting element substrate. With this configuration, since the pair of support pieces are supported by the optical component holder, bending of the optical component due to its own weight is suppressed. Further, since the optical component holder is provided on the light emitting element substrate, the light source unit can be handled easily.

It is a perspective view which shows the structure of the light source unit which concerns on embodiment of this invention. It is a figure which shows the structure of a light source unit, (A) is a front view, (B) is a bottom view, (C) is a side view. It is a figure for demonstrating the cross section of a light source unit, (A) is sectional drawing of a light source unit, (B) is a schematic diagram of the irradiation field corresponding to one LED. It is a disassembled perspective view of a light source unit. It is a figure which shows the structure of the flow-path groove | channel of a cooling unit, (A) is a top view, (B) is sectional drawing in the II line | wire of (A). It is explanatory drawing of a deformed rod lens, (A) is a schematic diagram which shows the side surface of a deformed rod lens with a line LED light source, (B) is a plane schematic diagram which shows a deformed rod lens with the arrangement | sequence of LED, (C) is a deformed rod It is a schematic diagram of the irradiation pattern made by control of the light of a lens. It is explanatory drawing of the modification of the deformed rod lens which is an optical component. It is a perspective view which shows the structure of the light source unit which concerns on the modification of this invention. It is a disassembled perspective view of the light source unit which concerns on the modification. It is explanatory drawing of the light control board which concerns on the modification, (A) is a schematic diagram which shows the side of a light control board with a line LED light source, (B) is a plane schematic diagram which shows a light control board with the arrangement | sequence of LED, C) is a schematic diagram of an irradiation pattern created by controlling the light of the light control plate. It is a perspective view which shows the structure of the light source unit which concerns on another modification, (A) is an upper perspective view, (B) is a lower perspective view. It is a disassembled perspective view of the light source unit which concerns on the modification. It is a figure which shows the structure of the cooling base body which concerns on the modification, (A) is a top view, (B) is sectional drawing in the II-II line of (A).

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing a configuration of a light source unit 1 according to the present embodiment. 2A and 2B are diagrams showing a configuration of the light source unit 1, in which FIG. 2A is a front view, FIG. 2B is a bottom view, and FIG. 2C is a side view. 3 is a diagram for explaining a cross section of the light source unit 1, FIG. 3A is a cross sectional view of the light source unit 1, and FIG. 3B is a schematic diagram of an irradiation pattern corresponding to one ultraviolet LED 30. It is.
The light source unit 1 is implemented by being incorporated in a printing apparatus that forms an image by ejecting ultraviolet curable ink that is cured by irradiation of ultraviolet rays onto a printing paper surface using an inkjet head. Specifically, the light source unit 1 is disposed on the printing paper conveyance path of the printing apparatus, facing the printing paper conveyance surface on the downstream side of the inkjet head, and coated with ultraviolet curable ink. By irradiating the line-shaped ultraviolet rays, the ultraviolet curable ink is quickly photocured and fixed on the printing paper surface.

  As shown in FIGS. 1 and 2, the light source unit 1 is formed in a quadrangular prism shape having an overall length L that is at least longer than the width of the printing paper (the length in the direction orthogonal to the transport direction). A substantially rectangular irradiation port 4 extending longer than the width of the printing paper is opened on the bottom surface 2 of the light source unit 1, and linear ultraviolet rays are irradiated from the irradiation port 4. The irradiation port 4 is provided with a deformed rod lens 6 as an optical component for controlling ultraviolet rays, and the control of the deformed rod lens 6 irradiates the position of the conveying surface with ultraviolet rays having a predetermined intensity. The irradiation port 4 is closed by the deformed rod lens 6, which will be described later.

  The light source unit 1 includes a cooling unit 8 on the upper side. The cooling unit 8 cools the light source unit 1 (more precisely, an ultraviolet LED 30 described later) by circulating cooling water as a refrigerant. A pair of joints 12 for introducing and discharging cooling water is disposed on the upper surface 10 of the cooling unit 8, and a tube through which the cooling water flows is connected to each joint 12. Details of the cooling unit 8 will be described later. On the upper surface 10 of the cooling unit 8, a mounting bracket 14 for mounting the light source unit 1 inside the printing apparatus is provided.

FIG. 4 is an exploded perspective view of the light source unit 1.
As shown in the figure, the light source unit 1 includes a light source substrate 20, a line LED light source 22, a lens holder 24, and a lens pressing plate 26, and further includes the cooling unit 8 and the deformed rod lens 6 described above. It has.
The light source substrate 20 is a rectangular plate-shaped substrate having a total length L, and the line LED light source 22 is configured by continuously mounting ultraviolet LEDs 30 on the light source substrate 20 in one direction. The light source substrate 20 is formed by using, for example, a high thermal conductivity material such as an aluminum material as a base material, and an insulating film or a circuit pattern is formed on the surface on the mounting surface side of the base material. Is connected.
The line LED light source 22 includes a plurality of the above-described ultraviolet LEDs 30 in a substantially rectangular box shape, and as described above, these ultraviolet LEDs 30 are arranged on the mounting surface of the light source substrate 20 at a constant pitch on a straight line along the longitudinal direction. As a result, line-shaped light is emitted. As shown in FIG. 3, the ultraviolet LED 30 includes an LED chip 60 as a light emitting element, a reflecting surface 61, and the like, and emits a predetermined amount of ultraviolet rays (peak wavelength 385 nm) necessary for curing the ultraviolet curable ink.

  The cooling unit 8 is in close contact with the back side of the mounting surface of the light source substrate 20 and cools each ultraviolet LED 30 of the line LED light source 22 through the light source substrate 20. Specifically, as shown in FIGS. 3 and 4, the cooling unit 8 includes a cooling base body 32 and the joint 12. The cooling base body 32 is a metal plate material having a surface 34 having substantially the same dimensions as the back surface of the light source substrate 20. A flow path groove 36 through which cooling water introduced / extracted from the joint 12 flows is formed on the surface 34 of the cooling base body 32, and the surface 34 of the cooling base body 32 is in close contact with the back surface of the light source substrate 20. Thus, the flow channel 36 is closed. The flow path groove 36 extends from one end portion to the other end portion of the light source substrate 20, and the cooling water flows through the flow path groove 36, whereby the light source substrate 20 is cooled uniformly.

FIG. 5 is a diagram showing the configuration of the flow channel 36 of the cooling unit 8, FIG. 5A is a plan view of the flow channel 36, and FIG. 5B is a cross-sectional view.
In the present embodiment, the flow channel 36 has a plurality of horizontally long elliptical recesses 36A and a communication portion 36B that communicates these horizontally long elliptical recesses 36A. The horizontally long elliptical concave portion 36 </ b> A is a concave portion having a flat bottom and is formed in an elliptical shape in plan view that is long in the longitudinal direction F <b> 1 of the cooling unit 8. These horizontally long elliptical recesses 36A are arranged along the longitudinal direction F1 of the cooling unit 8, and the end portions 36A1 of each horizontally long elliptical recess 36A are communicated with each other by the communication portion 36B. As shown in FIG. 5B, the communication portion 36B is a concave groove having a narrower width and a rectangular cross section than the horizontally long elliptical concave portion 36A. Through holes 36C to which the joints 12 are connected are formed in the horizontally long elliptical recesses 36A at both ends, and the cooling water introduced from one through hole 36C extends along the longitudinal direction to each horizontally long elliptical recess 36A. , And through the communication part 36B, it is discharged from the other through hole 36C.
In addition, an island 37 is formed in each horizontally long elliptical recess 36 </ b> A at the center thereof, that is, at a position corresponding to the line LED light source 22. Thereby, the heat generated by the line LED light source 22 is smoothly transferred to the island portion 37 through the light source substrate 20 and is efficiently transmitted to the cooling water flowing around the island portion 37, so that high cooling performance is obtained.

  As shown in FIGS. 4 and 5, the surface 34 of the cooling base body 32 is provided with a plurality of screw holes 36D at the edge thereof, and the light source substrate 20 is screwed to the screw holes 36D. Further, a packing groove 38 surrounding the flow path groove 36 is provided on the surface 34 of the cooling base body 32. A sealing material is fitted in the packing groove 38 to prevent leakage of cooling water from the gap between the light source substrate 20 and the cooling base body 32.

Since the cooling capacity of the cooling unit 8 increases in accordance with the amount of refrigerant flowing through the flow channel groove 36, a single piece in which the space between the through holes 36 </ b> C at both ends is expanded in the short direction F <b> 2 of the cooling base body 32 as much as possible. If it connects with a groove | channel, the cooling capacity as large as possible is obtained. However, since it is necessary to screw the cooling base body 32 to the light source substrate 20 in order to cover and close the channel groove 36, it is necessary to divide the space for providing the screw hole 36D on the surface 34 of the cooling base body 32. There is.
Therefore, in this flow channel groove 36, each of the horizontally long elliptical concave portions 36A is expanded as much as possible leaving a space for providing the packing groove 38 in the short direction F2 of the cooling base body 32. Are communicated with each other by a communication portion 36B that is narrow enough to leave a space for providing screw holes 36D and packing grooves 38 on both sides. Thereby, the flow path groove | channel 36 which maintains high cooling capability, ensuring the arrangement space of the screw hole 36D is obtained.

Further, in the cooling base body 32, if the area occupied by the channel groove 36 is not equal in the cross section in the short direction F2 at each point in the longitudinal direction F1, the channel resistance is generated in the longitudinal direction F1 and the cooling performance is uneven. .
Therefore, by forming the depth G (FIG. 5B) of the communication portion 36B deeper than the horizontally-long elliptical recess 36A, the cross-sectional area of the communication portion 36B is made equal to the cross-sectional area of the horizontally-long elliptical recess 36A. ing.
In addition, the island part 37 in each horizontally long elliptical recessed part 36A also has a shape that equalizes the area occupied by the channel groove 36 in the cross section in the short direction F2 of each point in the longitudinal direction F1.

6A and 6B are explanatory views of the deformed rod lens 6. FIG. 6A is a schematic diagram showing the side surface of the deformed rod lens 6 together with the line LED light source 22, and FIG. 6B is an array of the deformed rod lens 6 with the ultraviolet LEDs 30. FIG. 6C is a schematic diagram of an irradiation pattern created by controlling the light of the deformed rod lens 6.
As shown in the drawing, the deformed rod lens 6 is a transmissive optical component that extends along the line LED light source 22 and controls light emitted from the line LED light source 22 and transmitted therethrough. As described above, the light source unit 1 irradiates ultraviolet rays that are condensed on the conveyance surface of the printing apparatus, and therefore, the condensing optical system is used for the deformed rod lens 6. In the present embodiment, even if the distance from the irradiation port 4 to the transport surface H slightly changes due to an attachment error of the light source unit 1 or the like, the above-described FIG. As shown in A), the deformed rod lens 6 collimates the light from the line LED light source 22. Specifically, the deformed rod lens 6 is configured by bonding two cross-sectional plano-convex rod lenses 41 and 42 having different curvatures back to back with a transparent plate-like support plate 40 interposed therebetween. With this configuration, parallel light that is parallel over a predetermined irradiation distance M is obtained from the plano-convex rod lens 42 in cross section, and the distance from the light source unit 1 to the transport surface H is within this irradiation distance M range. Even if it changes, the light quantity on the conveyance surface H is kept constant.
As shown in FIG. 3B, an irradiation pattern P1 having a substantially circular light amount distribution is formed on the transport surface H by the single ultraviolet LED 30 and the deformed rod lens 6. Then, in the light source unit 1, by arranging the deformed rod lens 6 along the ultraviolet LEDs 30 arranged in a line, as shown in FIG. 6C, the irradiation patterns P1 adjacent to each other overlap each other. An irradiation pattern P2 connected in a shape is obtained.

  The lens holder 24 and the lens pressing plate 26 are support members that are arranged at positions that cover the deformed rod lens 6 along the line LED light source 22. Specifically, as shown in FIGS. 3 and 4, the lens holder 24 is formed in a rectangular shape with a size covering the mounting surface of the light source substrate 20, and is provided in close contact with the mounting surface of the light source substrate 20. . A lens storage opening 46 is provided in the surface of the lens holder 24. The lens storage opening 46 extends longer than the line LED light source 22 as shown in FIG. The line LED light source 22 is formed in a size to be accommodated. Then, as shown in FIG. 4, the deformed rod lens 6 is housed in the lens housing opening 46, and the line LED light source 22 is sealed in the lens housing opening 46 by the deformed rod lens 6.

  Specifically, as shown in FIGS. 3 and 6 (B), the edge of the support plate 40 protrudes from both sides of the deformed rod lens 6 so as to extend to the entire length in the longitudinal direction on both sides of the deformed rod lens 6. A support piece 44 is formed to extend over. On the other hand, as shown in FIG. 3 (A), the lens holder 24 has an edge 47 on the tip side of the lens housing opening 46 corresponding to the support pieces 44 on both sides of the deformed rod lens 6. A step portion 48 is formed to receive the support rod 44, and the deformed rod lens 6 is received in the lens storage opening 46 by receiving the support piece 44. The lens pressing plate 26 has the irradiation port 4 formed in the surface thereof, and the support piece 44 of the deformed rod lens 6 in which the edge 49 of the irradiation port 4 is stored in the lens storage opening 46 is sandwiched between the lens holders 24. Thus, the deformed rod lens 6 is held so as not to drop.

  As shown in FIG. 4, the lens holder 24, the lens holding plate 26, the light source substrate 20, and the cooling unit 8 are overlapped and fastened with a plurality of screws 50 (FIG. 1) to form one light source. Configured as unit 1.

And according to the light source unit 1 of such a structure, there exist the following effects.
That is, a pair of support pieces 44 extending along the edge are provided on both sides of the deformed rod lens 6 as an optical component, and the pair of support pieces 44 are supported to cover the line LED light source 22 (that is, each of the ultraviolet LEDs 30). The lens holder 24 disposed at the position is provided on the mounting surface of the light source substrate 20.
With this configuration, since the support piece 44 is supported by the lens holder 24, the deformation of the deformed rod lens 6 due to its own weight is suppressed. In addition, since the lens holder 24 is provided on the light source substrate 20, handling as one light source unit 1 is facilitated. Further, since the lens holder 24 is in close contact with the light source substrate 20, it is possible to prevent the light source substrate 20 from being bent.

Further, in the light source unit 1 of the present embodiment, the lens holder 24 is provided with a lens housing opening 46 that surrounds the line LED light source 22 and accommodates the deformed rod lens 6, and the lens housing opening 46 is formed by the deformed rod lens 6. The line LED light source 22 is closed, and the lens housing opening 46 is sealed.
As a result, ink droplets, paper dust, and the like on the printing paper are prevented from adhering to the line LED light source 22 (particularly the LED chip 60), and the occurrence of illuminance unevenness is suppressed.

  In addition to this, in the present embodiment, since the cooling unit 8 that cools each ultraviolet LED 30 of the line LED light source 22 is provided on the back surface of the light source substrate 20, the heat of the line LED light source 22 over the lens housing opening 46 is increased. The line LED light source 22 can be protected from heat by being cooled by the cooling unit 8 through the light source substrate 20 having high thermal conductivity.

In particular, according to the present embodiment, the cooling unit 8 has the flow channel groove 36 that forms a flow channel through which the cooling water flows between the back surfaces of the light source substrate 20, and the light source substrate is cooled by the cooling water that flows in the flow channel groove 36. The line LED light source 22 is cooled through 20.
Thereby, since a cooling water contacts the light source board | substrate 20 and cools, a big cooling effect is acquired.

  The above-described embodiment is merely an example of one aspect of the present invention, and can be arbitrarily modified and applied without departing from the spirit of the present invention.

In the above-described embodiment, each of the deformed rod lens 6 is configured such that each of the plano-convex rod lenses 41 and 42 and the support plate 40 are separate members, but the present invention is not limited thereto, as shown in FIG. Alternatively, the deformed rod lens 106 may be configured by integrally forming the cross-sectional plano-convex rod lens 141 and the support plate 140 and bonding another cross-section plano-convex rod lens 142 to the support plate 140. Similarly, as shown in FIG. 7B, a cross-sectional plano-convex rod lens 242 and a support plate 240 are integrally formed, and another cross-section plano-convex rod lens 241 is bonded to the support plate 240. The deformed rod lens 206 may be configured. Further, as shown in FIG. 7C, the deformed rod lens 306 may be formed by integrally forming the cross-sectional plano-convex rod lenses 341 and 342 and the support plate 340.
In addition to the configuration in which the support piece 44 is integrally formed on the edge portion of the support plate 40, as shown in FIG. 7D, support pieces 444 made of different members are connected to both edges of the support plate 440. The deformed rod lens 406 may be configured. In the deformed rod lens 6, a support plate 440 is provided integrally with the cross-sectional plano-convex rod lens 441, and the cross-section plano-convex rod lens 442 is bonded to the support plate 440.

In the embodiment described above, the light source unit 1 that forms the line light source by arranging the ultraviolet LEDs 30 in a straight line is illustrated, but the present invention is not limited thereto, and a plurality of ultraviolet LEDs 30 are appropriately distributed and arranged in a plane to emit planar light. It is good also as a structure to irradiate.
FIG. 8 is a perspective view showing a configuration of a light source unit 500 according to this modification, and FIG. 9 is an exploded perspective view of the light source unit 500. In these drawings, the members described in the above-described embodiment are denoted by the same reference numerals and description thereof is omitted.

  As shown in these drawings, the light source unit 500 includes a planar LED light source unit 522 configured by arranging a plurality of ultraviolet LEDs 30 vertically and horizontally at a predetermined pitch on the mounting surface of the light source substrate 20. The light source unit 500 is supported by an optical component holder 524 at a position where a light control plate 506 as an optical component for controlling the light of each ultraviolet LED 30 of the planar LED light source unit 522 covers the planar LED light source unit 522.

FIG. 10 is an explanatory diagram of the light control plate 506. FIG. 10A is a schematic diagram showing the side surface of the light control plate 506 together with the line LED light source 22, and FIG. 10B is an arrangement of the light control plate 506 with the ultraviolet LED 30. FIG. 10C is a schematic diagram of an irradiation pattern created by controlling the light of the light control plate 506. FIG.
As shown in these drawings, the light control plate 506 is a plate-like optical component configured by providing plano-convex lenses 543 and 547 for each ultraviolet LED 30 on the front and back surfaces of a transparent rectangular plate-like support plate 540. In the same manner as in the above-described embodiment, one ultraviolet LED 30 forms a substantially circular irradiation pattern P2, and the irradiation patterns P1 adjacent in the vertical and horizontal directions overlap to form an irradiation pattern P3.
Edges at both ends of the support plate 540 of the light control plate 506 are configured as support pieces 544. The optical component holder 524 is an L-shaped member having a stepped portion 48 that receives the support piece 544, and is fixed to both sides of the light source substrate 20 with the planar LED light source unit 522 interposed therebetween. Then, by fixing the support pieces 544 at both ends of the support plate 540 of the light control plate 506 to the pair of optical component holders 524 with screws or the like, the light control plate 506 is disposed at a position covering the planar LED light source unit 522. The
The step portion 48 of the optical component holder 524 extends along the edge of the planar LED light source unit 522, and the support piece 544 is supported by the step portion 48, so that the deflection of the light control plate 506 is suppressed. .
Further, in the support plate 540 of the light control plate 506, by reducing the distance δ between the edge 548 on the side where the support piece 544 is not provided and the nearest plano-convex lenses 543 and 544, these are reduced. Plano-convex lenses 543 and 544 are disposed up to a position close to the edge 548.
Thereby, a plurality of light source units 500 can be arranged in a line so that the edges 548 are connected to each other, and a light source device that expands the irradiation range while suppressing uneven illuminance between the light source units 500 can also be configured.

In the above-described embodiment, the front and back surfaces of the support plate 40 having the support piece 44 are not limited to the plano-convex rod lenses 41 and 42 and the plano-convex lenses 543 and 547, and an arbitrary light control unit may be provided. it can.
Thus, since it is set as the structure which provides a light control part in each of the front and back of the support plate 40 which has the support piece 44, arbitrary irradiation patterns are realizable by changing a light control part.

  In the above-described embodiment, the configuration in which the cooling unit 8 that cools the ultraviolet LED 30 forms the flow path of the coolant between the light source substrate 20 is illustrated, but the present invention is not limited thereto. That is, as in the light source unit 500 shown in FIG. 9, the cooling base body 32 is brought into close contact with the back surface of the light source substrate 20 in an upside down posture, and the flow channel groove 36 (see FIG. The cooling base body 32 may be covered with a cover plate 555 that forms a flow path between the cooling unit body 508 and the cooling unit 508.

In the above-described embodiment, the case where the light source unit 1 includes one light source substrate 20 is illustrated. However, the present invention is not limited to this, and a plurality of light source substrates 20 are connected in the longitudinal direction to generate linear light. The total length may be extended.
Hereinafter, the light source unit 600 having such a configuration will be described.

FIG. 11 is a perspective view illustrating a configuration of a light source unit 600 according to the present modification, in which FIG. 11A is an upper perspective view and FIG. 11B is a lower perspective view. FIG. 12 is an exploded perspective view of the light source unit 600. In addition, in the same figure, the same code | symbol is attached | subjected about the member demonstrated by embodiment mentioned above, and the description is abbreviate | omitted.
As shown in FIG. 11A, the light source unit 600 includes a unit main body 603, a cooling unit 608, and a mounting bracket 614.
The unit main body 603 is formed in a substantially quadrangular prism shape that is at least longer than the width of the recording sheet (the length in the direction orthogonal to the conveying direction). As shown in FIG. 12, the light source substrate 20, the ultraviolet LED 30, and the lens holder 624 described above. , A lens holding plate 26, a deformed rod lens 6, and a bus bar 623.
The unit body 603 is provided with two light source substrates 20, and these light source substrates 20 are connected and arranged in a line in the length direction so that the total length of the light source unit 1 described in the above embodiment is provided. Has been extended.

The bus bar 623 is, for example, a copper bus bar that applies a large current to each of the light source substrates 20, and is an electrical wiring member (conductive member) that electrically connects each of the light source substrates 20 in series. As shown in FIG. 12, the bus bars 623 extend on both sides of the ultraviolet LEDs 30 along the arrangement of the ultraviolet LEDs 30, and the ultraviolet LEDs 30 are electrically connected in parallel between the bus bars 623.
Since a large current can be supplied to each light source substrate 20 through the bus bar 623 in this way, even when a plurality of light source substrates 20 are connected in series, a current is stably supplied to each of the ultraviolet LEDs 30 of each light source substrate 20. Is done.
The bus bar 623 has a rectangular plate shape extending along the arrangement of the ultraviolet LEDs 30, and the front and back surfaces thereof are provided so as to be perpendicular to the mounting surface of the light source substrate 20. Space is saved compared with the case of providing.

  The lens holder 624 is a holder that accommodates the deformed rod lens 6 in the same manner as the lens holder 24 of the above-described embodiment. The deformed rod lens 6 is provided for each light source substrate 20, and these deformed rod lenses 6 are linearly connected and stored in the lens storage opening 646. Further, the bus housing 623 is housed in the lens housing opening 646 between the inner wall and the ultraviolet LED 30 to shield the ultraviolet light from the ultraviolet LED 30 toward the inner wall.

The cooling unit 608 is provided for each light source substrate 20 and cools the light source substrate 20. The cooling unit 608 is formed in a plate shape having a length substantially the same as the entire length of the light source substrate 20. A mounting plate 614 with high thermal conductivity is sandwiched between the mounting surface and the entire surface on the back side of the mounting surface.
As shown in FIG. 12, the cooling unit 608 includes a cooling base body 632, a lid plate 633, and a joint 12, and the cooling base body 632 and the lid plate 633 form the cooling unit 608. A plate-shaped main body is configured.

As in the cooling unit 508 described with reference to FIG. 9, the cooling unit 608 is provided with a channel groove 636 formed of a concave portion on the upper surface 632A of the cooling base body 632, and this upper surface 632A is formed on the cover plate 655. The cooling water passage is formed by covering the bottom surface 608A with the bottom surface 608A of the cooling base body 632 in close contact with the back surface of the light source substrate 20.
The joint 12 is connected to both ends of the flow path groove 636 of the cooling base body 632 through the cover plate 655, cooling water is introduced from the joint 12 at one end, flows through the flow path groove 636, and the joint at the other end. 12 can be discharged. When the cooling water flows through the flow channel groove 636, the bottom surface 8 </ b> A is maintained in a cooled state, and the light source substrate 20 in close contact with the bottom surface 8 </ b> A is entirely cooled in the longitudinal direction.

  As shown in FIGS. 11 and 12, the mounting bracket 614 includes a mounting piece 614 </ b> A that extends along the longitudinal direction of the light source unit 600 on the upper side of the cooling unit 608. A plurality of (two in the illustrated example) attachment holes 615 are formed in the attachment piece 614A in the longitudinal direction, and the attachment holes 615 are fixed to the printing apparatus through screws or the like. At the time of fixing, the light source unit 600 is fixed so as to extend substantially parallel to the printing surface of the recording sheet, thereby preventing uneven irradiation on the recording sheet.

  As shown in FIG. 11, the mounting bracket 614 is formed by bending a plate material having a length over the entire length of the light source unit 600 into an L-shaped cross section, so that rigidity is increased, and one side surface of the mounting bracket 614 is the mounting piece 614A. Therefore, the light source unit 600 is prevented from being bent by its own weight. Furthermore, in this light source unit 600, the L-shaped other side surface of the mounting bracket 614 is used for the mounting base 614B for mounting and fixing the plurality of light source substrates 20 and the plurality of cooling units 608 on the front and back.

  That is, the plurality of light source substrates 20 are connected to the mounting bracket 614 that has a plurality of light source substrates 20 connected to each other in the longitudinal direction and can irradiate light having a long overall length, and has an L-shaped cross section to increase rigidity. By constructing the light source unit 600 by attaching a plurality of cooling units 608, the light source unit 600 that is less likely to bend in the longitudinal direction is easily configured. Since the mounting base 614B is interposed between the light source substrate 20 and the cooling unit 608, the mounting bracket 614 has a high thermal conductivity so that the mounting base 614B does not hinder the cooling of the light source substrate 20 by the cooling unit 608. Formed of the material.

Here, in the cooling unit 8 of the above-described embodiment, as shown in FIG. 5, each of the horizontally long elliptical concave portions 36 </ b> A is widened as much as possible in the short direction F <b> 2 of the cooling base body 32. The flow path groove 36 that maintains a high cooling capacity while securing the space for arranging the screw holes 36D by communicating between the 36A through the communication portions 36B that are narrow enough to leave spaces for providing the screw holes 36D on both sides. It was set as the structure which obtains.
Further, in this configuration, by making the depth G (FIG. 5B) deeper than the horizontally-long elliptical concave portion 36A, the cross-sectional area of the communicating portion 36B is made equal to the cross-sectional area of the horizontally-long elliptical concave portion 36A. I have to.
However, if the depth G of the communication part 36B is increased, the cooling base body 32 becomes thicker and the weight increases, and the heat recovery efficiency of the cooling water also decreases.
In particular, in the light source unit 600 shown in FIG. 11 of the present modification, the influence of the weight increase is large because the total length is long, and the mounting bracket 614 is interposed between the cooling unit 608 and the unit main body 603, so that the heat recovery is performed. The effect of efficiency reduction is also great.
Therefore, in the cooling unit 608 of this modification, the following is formed on the surface 634 of the cooling base body 632.

13A and 13B are diagrams showing the configuration of the cooling base body 632, FIG. 13A is a plan view, and FIG. 1B is a cross-sectional view taken along line II-II in FIG. In addition, illustration of the packing groove | channel 38 is abbreviate | omitted in this figure.
As shown in the figure, in the cooling base body 632, a pair of edge portions 631 opposed to each other along the longitudinal direction F1 are formed on the surface 634 differently (in a so-called staggered manner) with screw holes 636D for screwing. A formation space 636E is provided. The remaining space between the pair of edge portions 631 is provided with a channel groove 636 and a recess 636A extending in the longitudinal direction F1. The bottom of the recess 636A has a flat surface, and through holes 636C to which the joint 12 is connected are formed at both ends.
In such a configuration, the recess 636A is bent between the formation space 636E of the screw hole 636D of the pair of edges 631 and extends in the longitudinal direction F1, and the width in the short direction F2 at each point in the longitudinal direction F1. Is substantially constant, the cross-sectional area of each point can be made equal without changing the depth G.
Thereby, the thickness of the cooling base body 632 can be reduced, the weight can be reduced, and the heat recovery efficiency of the cooling water can be improved.

In the embodiment and the modification described above, the refrigerant flowing through the cooling units 8, 508, and 608 is not limited to cooling water, and any refrigerant can be used.
In the above-described embodiment, an ultraviolet LED is exemplified as an LED that is an example of a light emitting element. However, the present invention is not limited to this, and an LED that emits light of another wavelength may be used. Furthermore, not only LED but arbitrary light emitting elements, such as organic EL, can also be used.
Further, the light source unit according to the present invention can be widely applied besides the light source for curing ultraviolet curable ink.

1, 100, 600 Light source unit 4 Irradiation port 6, 106, 206, 306, 406 Deformed rod lens (optical component)
8,508,608 Cooling unit (cooling means)
20 Light source substrate (light emitting element substrate, other members)
22 Line LED light source 24, 624 Lens holder (optical component holder)
26 Lens holding plate 30 UV LED (light emitting element)
32, 632 Cooling base body 36, 636 Channel groove 36A Horizontal oblong recess 36C, 636C Through hole 36D, 636D Screw hole 37 Communication portion 41, 42 Plano-convex rod lens (first light control portion, second light control) Part)
44, 544 Supporting piece 46 Lens storage opening (storage opening)
60 LED chip 522 Planar LED light source unit 524 Optical component holder 506 Light control plate (optical component)
543, 547 Plano-convex lens (first light control unit, second light control unit)
555, 655 Cover plate (other members)
636A Concave

Claims (6)

A light emitting element substrate having a plurality of light emitting elements arranged on the surface;
An optical component that covers each of the light emitting elements to control light, and
Provide a pair of support pieces extending along the edge on both sides of the optical component,
A light source unit comprising: an optical component holder disposed on a position where the pair of support pieces of the optical component are supported to cover each of the light emitting elements. The optical component is
A light control unit that controls the incident light that is emitted from the light emitting element; and
The light control unit is provided on a surface, and transmits a light emitted from the light control unit, and a support plate having the pair of support pieces at each end sandwiching the light control unit. Item 2. The light source unit according to Item 1.   The optical component holder is provided with a housing opening that surrounds the light emitting element and accommodates the optical component, and the light emitting element is closed by the optical component to seal each of the light emitting elements. The light source unit according to claim 1 or 2.   The light source unit according to any one of claims 1 to 3, further comprising a cooling unit that cools each of the light emitting elements on a back surface of the light emitting element substrate.   5. The cooling device according to claim 4, wherein the cooling means is provided with a flow channel groove that forms a flow channel for a coolant, and each of the light emitting elements is cooled through the light emitting device substrate by the coolant flowing in the flow channel. Light source unit. The cooling means is a cooling base body in which the flow channel is formed on the surface and is screwed so that another member contacts the surface, and the flow channel is constituted by the other member and the flow channel. With
6. The surface of the cooling base body is provided with a space for forming screw holes for screwing at opposite edges, and the flow path groove is formed in the remaining space. Light source unit.