Patent Application
20130335957
The present invention relates to a light irradiation device capable of irradiating, for example, line-shaped light using a plurality of LEDs, and in particular to a light irradiation device appropriately used for inspection such as checking presence or absence of a crack in a predetermined irradiation region of a work piece (product), reading a mark and the like.
In recent years, there have been many integrated circuits which are low-voltage driven, and an output voltage required for a switching power supply device is also being lowered in voltage. As a result, a specification of a power supply device has a tendency to be lower in voltage but larger in current, and in order to suppress an electric resistance of not only an output circuit of the power supply device but also each current path inside the power supply device, a bus bar (power-feeding member) is used as a conductive member having a necessary but not a sufficient cross-section area, as shown in Patent Literature 1.
And the present applicant considers to provide a bus bar on each LED wiring substrate in a line light irradiation device having a plurality of substantially long sized LED wiring substrates and a casing for accommodating the LED wiring substrates. It is noted that, in an LED wiring substrate without using a bus bar, since a width of the LED wiring substrate is restricted to an accommodation width of a casing, the power-feeding line becomes thin and there may arise a problem that the line may be burned and disconnected in the case where required electric capacity becomes larger.
Conventionally, connection of bus bars provided on the LED wiring substrates is performed by co-fastening the end portions of the bus bars of the adjacent LED wiring substrates with screw members via a connection plate (for example, a copper plate) having conductivity at each end portion.
However, in a structure of co-fastening with screw members, there is a problem that the number of parts such as connection plate and screw member, etc., is increased and the number of assembling man-hours is increased. Further, in a configuration that the end portions of the bus bar of the adjacent LED wiring substrates are connected to each other via the connection plate, there is a problem that the connection becomes difficult in the case where a position of a screw hole formed in the bus bar and a position of a screw hole of the connection plate are displaced at the time of connection. In the assembly of connecting the connection plate to the bus bar after fixing the LED wiring substrate to the casing, there is a problem that a working space for connecting the bus bar is narrow and workability becomes extremely bad.
Therefore, the present invention has been made in order to solve the above problem at once and a main expected object thereof is to allow a width of an LED wiring substrate to be compact and to reduce the number of assembly parts and assembly man-hours.
Accordingly, a line light irradiation device according to the present invention is a light irradiation device comprising a plurality of substantially long-sized LED wiring substrates arranged in a longitudinal direction, each of the LED wiring substrates including: a plurality of LEDs provided in a line shape along the longitudinal direction; and power-feeding line members provided in parallel with an arrangement direction of the plurality of LEDs for supplying electric power to the plurality of LEDs, wherein the power-feeding line members are provided above an LED mounting surface of each of the LED wiring substrates, and in the adjacent LED wiring substrates, the power-feeding line members provided in one of the adjacent LED wiring substrates include contact terminals provided to extend outward in the longitudinal direction and contact with the power-feeding line members of the other LED wiring substrate. Here, the phrase “provided to extend outward in the longitudinal direction” means that the contact terminals are protruding outward from the LED wiring substrate in plan view.
With a configuration like this, since the power-feeding line member is provided above the LED mounting surface, the power-feeding line member can be made thick in accordance with a required electric capacity irrespective of a width of the LED wiring substrate, and the width of the LED wiring substrate can be made compact. In addition, since the contact terminals provided in the power-feeding line members provided in one of the adjacent LED wiring substrates contact with the power-feeding line members of the other LED wiring substrate, parts of a connection plate and a screw member required for a co-fastening structure can be made unnecessary, and the number of parts can be reduced. Further, since the power-feeding line members of the adjacent LED wiring substrates are electrically connected to each other by the contact terminals, the number of assembling man-hours can be also reduced.
It is desirable that the contact terminals are integrally formed with the power-feeding line members and elastically deformed to be pressed in contact with the power-feeding line members of the adjacent LED wiring substrate. With this, since the power-feeding line members and the contact terminals are integrally formed, the number of parts of the LED wiring substrate can be reduced and the number of assembling man-hours of the LED wiring substrate can be also reduced. Further, since the contact terminals are elastically deformed to be pressed in contact with the power-feeding line members, the electric contact between the power-feeding line members of the adjacent LED wiring substrates can be surely performed.
It is desirable to provide a casing having a bottom wall part extending in the longitudinal direction and a pair of left and right side wall parts extending upward from both sides in the longitudinal direction of the bottom wall part, with the plurality of LED wiring substrates being arranged on the bottom wall part, wherein, by fixing the plurality of LED wiring substrates to the bottom wall part, the contact terminals are elastically deformed to be pressed in contact with upper surfaces of the power-feeding line members of the adjacent LED wiring substrate. With this, at the same time of fixing the LED wiring substrate to the bottom wall part, a power caused by the fixing can be effectively used and the contact terminals can be surely brought into contact with the power-feeding line members of the adjacent LED wiring substrate.
It is desirable that one of the pair of power-feeding line members has the contact terminal at one end part in the longitudinal direction and the other of the pair of power-feeding line members has the contact terminal at the other end part in the longitudinal direction. With this, the structure of each LED wiring substrate can be commonly shared and the number of parts can be reduced. Further, since a reaction force (force leaving from the bottom wall part) received by pressing one of the power-feeding line members in contact with the power-feeding line member of the adjacent LED wiring substrate and a force (force toward the bottom wall part) which the other power-feeding line members receive from the contact terminals of the power-feeding line members of the adjacent LED wiring substrate counteract as cancelling each other, the LED wiring substrate can be stably fixed.
Further, it may be also considered that each of the pair of power-feeding line members has the contact terminal at one end part in the longitudinal direction. With this, the structure of each LED wiring substrate can be commonly shared and the number of parts can be reduced, and in the case where some of the plurality of LED wiring substrates accommodated in the casing are exchanged, it can be made easy to exchange.
In order to effectively use both sides of the plurality of LEDs to be able to withstand larger current in the LED wiring substrate, it is desirable that the power-feeding line members are paired so as to interpose the plurality of LEDs therebetween.
It is desirable that the power-feeding line members are fixed with screws to a surface implementing spacer soldered to the LED mounting surface of the LED wiring substrate. With this, the power-feeding line members can be made detachable with respect to the LED wiring substrate and the power-feeding line members can be variously exchanged.
According to the present invention like this, the width of the LED wiring substrate can be made compact and the number of assembly parts and number of assembling man-hours can be reduced.
Next, one embodiment of a line light irradiation device 100 according to the present invention is described referring to the drawings.
The line light irradiation device 100 according to the present embodiment is adapted to irradiate line shaped light to, for example, a predetermined irradiation region of an inspection object (work) and it is used for such as a product inspection system, etc., which photographs the predetermined irradiation region with a photographing device (not shown), captures obtained image data with an image processing device (not shown) to perform an automatic inspection of checking presence or absence of a defect such as, e.g., a crack or dirt, a foreign matter in liquid, or mark inspection.
Specifically, as shown in
As shown in
The LED substrate 3 is a long-sized substrate mounting a plurality of LEDs 31. Specifically, the LED substrate 3 is formed by machine-mounting the plurality of LEDs 31 to be arranged in one or more lines (one line in
This LED substrate 3 is fixed to an upper surface of the bottom wall part 21 of the casing 2. And regarding this LED substrate 3, a longer side direction side surface 3a of the LED substrate 3 contacts with a substrate contacting surface 211 which is a substrate positioning structure provided along the longitudinal direction on the bottom wall part 21, and the LED substrate 3 is thereby positioned to the casing 2 in a lateral direction (a direction perpendicular to the longitudinal direction).
The rod lens 4 is a condenser lens of a generally circular shape with an equal cross-section having a generally same length as a length of each of the left and right side walls 22 and 23 of the casing 2. This rod lens 4 is provided along the longitudinal direction above the LED substrate 3 inside the casing 2 and is fixed to be in a predetermined position with respect to the plurality of LEDs 31 mounted on the LED substrate 3 by a fixing mechanism 5 to be described later. Specifically, the rod lens 4 is fixed by the fixing mechanism 5 in a manner such that an optical axis C2 of the rod lens 4 coincides with the optical axes C1 of the plurality of LEDs 31 and that the rod lens 4 is spaced a predetermined distance with respect to the plurality of LEDs 31. In addition, the light transmission plate 6 such as a diffusion plate and a protection cover is provided in a front (upper portion) in a light outgoing side of the rod lens 4, and since this light transmission plate 6 is thermally expanded, it is attached by a slide groove 7 with a slight play formed in an inner surface of each of the left and right side walls 22 and 23.
As shown in
Especially, as shown in
Especially, as shown in
And a distance between the inward surfaces 51b of the two projected rim parts 51 is generally identical to the distance between the outward surfaces 52b of the two notch portions 52, and the inward surfaces 51b of the projected rim parts 51 are in contact with the outward surfaces 52b of the notch portions 52 in a state that the upward surfaces 51a of the projected rim parts 51 are in contact with the downward surfaces 52a of the notch portions 52. Thus, the rod lens 4 can be positioned with respect to the casing 2 in the vertical direction as well as in the horizontal direction. That is, the optical axis C1 of each LED 31 on the LED substrate 3 positioned in the lateral direction with respect to the casing 2 coincides with the optical axis C2 of the rod lens 4 positioned in the lateral direction with respect to the casing 2.
The concave groove 53 is provided along the longitudinal direction above the projected rim part 51 to extend over from one end to the other end in the longitudinal direction in the inner surface of each of the left and right side wall parts 22 and 23. This concave groove 53 is formed in a manner such that the elastic body 54 is fit thereto in a state that the downward surface 52a of the notch portion 52 is in contact with the upward surface 51a of the projected rim part 51 and is formed in a position where the elastic body 54 contacts with the side peripheral surface of the rod lens 4.
The elastic body 54 is a linear tube having flexibility which is detachably provided in the concave groove 53 and which is a silicon tube excellent in heat resistance and corrosion resistance in the present embodiment. This elastic body is fit to the concave groove 53 in a state that the downward surface 52a of the notch portion 52 is in contact with the upward surface 51a of the projected rim part 51 and is brought into contact with the side peripheral surface of the upper side portion above the notch 52 in the rod lens 4 to thereby press the notch portion 52 to the projected rim part 51.
Thus, the plurality of LED wiring substrates 3 of the present embodiment are arranged in the longitudinal direction on an upper surface of the bottom wall part 21 of the casing 2, and as shown in
The pair of power-feeding line members 32a and 32b are provided above an LED mounting surface (upper surface 3b of the wiring substrate) of the LED wiring substrate 3 so as to be separated from the LED mounting surface 3b, and each of the power-feeding line members 32a and 32b is formed to have a long-sized shape provided along each of the longitudinal side surfaces of the LED wiring substrate 3.
As shown in
In addition, each of the power-feeding line members 32a and 32b is arranged between the longitudinal side surface of the LED wiring substrate 3 and the LEDs 31 in a transverse direction in plan view (see
And as shown in
Further, the contact terminals 321a and 321b are provided to be slightly bent upward from the end parts of the power-feeding line members 32a and 32b, and there are formed contact portions 322a and 322b contacting with the power-feeding line members 32a and 32b adjacent to the tip end portions thereof. A distance L1 between the lower end portions of these contact portions 322a and 322b and the upper surface 3b of the LED wiring substrate 3 is set to be slightly smaller than a distance L2 between the upper surfaces of the power-feeding line members 32a and 32b and the upper surface 3b of the LED wiring substrate 3.
Specifically, as shown in
In more detail, since the distance L1 between the contact portions 322a and 322b and the LED wiring substrate 3 is set to be slightly smaller than the distance L2 between the power-feeding line members 32a and 32b and the LED wiring substrate 3, in the case where the LED wiring substrate 3 is fastened with screws to the bottom wall part 21, the contact terminals 321a and 321b are elastically deformed and the contact portions 322a and 322b thereof are pressed in contact with an upper surface of the power-feeding line member of the adjacent LED wiring substrate 3. It is noted that, since a reaction force (force leaving from the bottom wall part 21) received by pressing the one side power-feeding line member 32a in contact with the power-feeding line member 32a of the adjacent LED wiring substrate 3 and a force (force toward the bottom wall part 21) which the other power-feeding line member 32b receives from the contact terminal 321b of the power-feeding line member 32b of the adjacent LED wiring substrate 3 counteract as cancelling each other, therefore it becomes possible to stably fix the LED wiring substrate 3.
It is noted that, as shown in
Next, an assembling procedure of the line light irradiation device 100 configured like this is described referring to
First, pultrusion-molding or extrusion-molding is performed, and the plurality of LED wiring substrates 3 are accommodated in the casing 2 which has been subjected to a prescribed process for fixing the front and rear side walls 24 and 25 to both end portions. As a method of accommodating these LED wiring substrates 3, the LED wiring substrates 3 are accommodated in the casing 2 one by one. In the case of accommodating a second LED wiring substrate 3 and thereafter, the accommodation is performed in a manner such that the contact terminal 321a (or 321b) of the previously accommodated LED wiring substrate 3 and the contact terminal 321b (or 321a) of the LED wiring substrate 3 to be accommodated are slid to be in contact with the upper surfaces of the power-feeding line members 32a and 32b, respectively. After all of the LED wiring substrates 3 are accommodate in this way, each LED wiring substrate 3 is fastened to the bottom wall part 21 with screws. Thus, the electrical connection of each LED wiring substrate 3 can be made sure. Then, the rod lens 4 is accommodated, for example, through an upper part opening of the casing 2. In a state of accommodating this rod lens 4 in the casing, the notch portion 52 of the rod lens 4 and the projected rim part 51 of the casing 2 are contacted, whereby the rod lens 2 is vertically and laterally positioned to the casing 2.
Then, the silicon tubes 54 formed of two elastic bodies are fit into the concave grooves 53 of the left and right side walls 22 and 23.
And after fitting the silicon tubes 54 to fix the rod lens 4, the light transmission plate 6 is slid to be attached to the sliding groove 7, and thereafter the rear side wall 25 is fastened to the left and right side walls 22 and 23 with screws to thereby assemble the line light irradiation device 100.
According to the line light irradiation device 100 according to the present embodiment configured like this, since the power-feeding line members 32a and 32b are provided above the LED mounting surface 3b, by making the power-feeding line members 32a and 32b thick irrespective of a width of the LED wiring substrate 3, it is possible to meet a required electric capacity, and the width of the LED wiring substrate 3 can be made compact. In addition, since the contact terminals 321a and 321b provided in the power-feeding line members 32a and 32b provided in one of the adjacent LED wiring substrates 3 are pressed in contact with the power-feeding line members 32a and 32b of the other LED wiring substrate 3, parts of a connection plate and a screw member required for a co-fastening structure can be made unnecessary, and the number of parts can be reduced. Further, since the power-feeding line members 32a and 32b of the adjacent LED wiring substrates 3 are electrically connected to each other by the contact terminals 321a and 321b, the number of assembling man-hours can be also reduced.
It is noted that the present invention should not be limited to the embodiment described above. For example, as shown in
Further, as shown in
Further, in the embodiment, although an example of providing a pair of power-feeding line members on the LED wiring substrate is shown, it may be configured that one power-feeding line member 32c is provided on the LED wiring substrate 3 as shown in
Moreover, as shown in
In addition, although the contact terminals of the embodiment are provided to be bent upward from the end portion of the power-feeding line member to be pressed in contact with the upper surface of the power-feeding line member of the adjacent LED wiring substrate, it is not limited to this. For example, as shown in
Furthermore, as shown in
In addition, it is needless to say that a part or a whole of the above described embodiments and modifications may be appropriately combined and the present invention is not limited to the above embodiments and various modifications may be made in a range unless deviated from the spirit thereof.
According to the present invention, a width of an LED wiring substrate can be made compact and the number of assembling parts and assembling man-hours can be reduced.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2011-048240 | Mar 2011 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP2012/053665 | 2/16/2012 | WO | 00 | 7/5/2013 |
