JP3244360B2 - Linear light source - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear light source used in a copying machine, a facsimile or the like.

[0002]

2. Description of the Related Art Conventionally, a linear light source is disclosed in, for example, Japanese Patent Application Laid-Open No. 4-44.
No. 368 discloses this as shown in FIG. A light emitting diode 41 is mounted on an electrode 43 on a substrate 42 and wired. In addition, the frame body 44 is formed by integrally molding the lens portion 45 and the reflection frame portion 46, and has an advantage that the attachment of the lens portion 45 and the reflection frame portion 46 is unnecessary and dust does not enter through a gap between the two. Then, the boss portion 47 formed on the reflection frame portion 46 is fixed to the substrate 42 by heat welding.
Although the fixing tool 48 is inserted between the lens part 45 and the substrate 42, the upper surface of the fixing tool 48 and the lens part 4 are inserted so as to be easily inserted.
A gap is provided between the bottom surfaces of 5. And fixture 4
8 is fixed by an adhesive 49.

[0003]

However, in the above-mentioned linear light source, the fixing tool 48 is fixed with the adhesive 49, so that it takes a long working time, and if it is moved after bonding, the bonding strength becomes insufficient and it comes off. There is a first disadvantage. Since the boss portion 47 of the reflection frame portion 46 is thermally welded to the substrate 42, there is a second disadvantage that the operation time is long. When the light emitting diode 41 is further turned on, the substrate 42 warps in the longitudinal direction due to heat generation. Therefore, the light emitting diode 41 and the lens unit 4
There is a third drawback that the distance from No. 5 cannot be kept constant. Accordingly, the present invention has been made in view of the conventional drawbacks, and provides a linear light source in which a fixing device is not sufficiently fixed, a substrate can be easily fixed, and a distance between a light emitting diode and a lens unit can be kept constant.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a frame body in which a lower part is opened and a groove is formed in a longitudinal direction of both inner side surfaces having a substantially U-shaped cross section. A long substrate housed in close contact with the plurality of light emitting diodes, and a plurality of light emitting diodes placed in a line in the longitudinal direction on the substrate, and a fixture substantially abutting on the end surface of the frame body and arranged on the substrate. The frame has a lens portion located above the light emitting diode, and the fixture is fitted in the gap between the bottom surface of the lens portion and the substrate, and the engaging portion formed on the fixture is formed on the substrate. It is provided so as to be fitted to the engaging portion.

The present invention more desirably mounts an electric component on a substrate so as to be in contact with the bottom surface of the lens portion.

[0006]

According to the present invention, as described above, the fixture is fitted into the gap between the substrate and the bottom surface of the lens portion, and is also fitted with the substrate.
Fixation is sufficient and does not come off. Then, it is sufficient that the substrate is inserted into the groove of the frame, and heat welding or the like is unnecessary, so that the work of fixing the substrate and the frame becomes easy.

Even if the substrate warps due to heat generation or the like, since the electric parts on the substrate and the lens portion are in contact with each other, the distance between the substrate and the lens portion can be maintained at a predetermined value. The distance can be kept constant.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 is a cross-sectional view of a linear light source according to the present embodiment, FIG. 2 is a partially exploded perspective view of a portion A of FIG. 1, FIG. 3 is a cross-sectional view of a line BB of FIG. 1, and FIG. FIG. 5 is a sectional view taken along the line DD in FIG. In these figures, a frame 1 is formed by extruding a lens portion 2 and a reflection frame portion 3 into a long piece, for example, 324 mm in length. The cross-sectional shape of the frame body 1 is substantially U-shaped with the lower part opened, the lens part 2 forms an upper thick part, and the reflection frame part 3 forms two side surfaces.

The lens portion 2 is made of, for example, a transparent polycarbonate resin or the like, and has a convex lens having a predetermined radius of curvature formed on each of the front surface and the rear surface.

The reflection frame portion 3 is made of, for example, a polycarbonate resin containing titanium dioxide, and has reflection surfaces 4 and 5 which are inclined so as to expand upward. Grooves 6, so as to be connected to the reflecting surfaces 4, 5 and located below them,
7 are formed on both inner side surfaces of the frame 1. Desirably, other grooves 8 and 9 and overhang portions 10 and 11 are formed so as to be connected to the grooves 6 and 7 and located below them.

The substrate 12 has a thickness of about 0.8 mm and a width of 4 m, for example.
It is a long one made of glass epoxy resin or the like having a length of 328 mm. A power supply pattern 13 made of copper foil or the like is formed in a predetermined shape on the surface thereof, and another power supply pattern is formed on the surface separately from the pattern 13. The substrate 12 is housed in close contact with the grooves 6 and 7 of the frame 1.

The plurality of light-emitting diodes 14 are mounted and fixed on the power supply pattern 13 via a conductive adhesive so as to be aligned substantially on a straight line.
m. The light emitting diode 14 has, for example, 0.2 on each side.
It is made of gallium phosphide, gallium arsenide phosphide, or the like having a substantially die shape of about 0.4 mm, each of which is wired with a thin metal wire.

Preferably, an electric component 15 such as a resistor is positioned between the light emitting diodes 14.
Are mounted and fixed on the power supply pattern 13 on the substrate 12, and are in contact with the bottom surface of the lens unit 2. According to a known circuit connection, for example, a plurality of light emitting diodes 14 and resistors 15
Are connected in series, and the groups are connected in parallel. As described above, since the upper surface of the resistor 15 and the lens unit 2 are in contact with each other, the distance between the substrate 12 and the lens unit 2 is kept constant over the entire longitudinal direction of the substrate 12. For example, a chip capacitor is used as the electric component 15.
This chip capacitor is connected in parallel to the power supply pattern 13 and another power supply pattern, and is used for voltage smoothing.

The fixtures 16 and 17 are located in the vicinity of the left end face 18 and the right end face 19 of the frame body 1 and both the lens section 2 and the substrate 1
2 are provided so as to close gaps at both ends. The fixture 16 is made of, for example, a molded product of a polycarbonate resin, and includes a side surface portion 20, wall portions 21, 22, 23, a bottom portion 24, an overhang portion 25, and an engagement portion, that is, a protrusion portion 26. When viewed from the side, the bottom surface of the bottom portion 24 has a step-like shape such that the height near the tip is higher than the near side.
The bottom portion 24 has a protruding portion 24a protruding outward from the wall portions 21 and 23 on the near side. The side surface portion 20 is connected to the bottom portion 24 and is formed substantially at right angles to the bottom portion 24, and the wall portions 21, 22, and 23 are connected to the side surface portion 20 and are connected to the bottom portion 2.
It is formed so that the height becomes smaller as it goes to the front end connected to 4. In the vicinity of the tip of the bottom 24 of the projection 26, the projection 26 is formed in a substantially columnar shape downward. Overhang 2
5 is connected to the center wall portion 22 and is formed above the wall portion 22 so as to be substantially horizontal.

The front side of the bottom 24 of the fixture 16 has a groove 6,
7, the tip side of the bottom 24 is located on the substrate 12, and the protrusion 26 is provided on the engaging portion of the substrate 12, that is, the through hole 2.
7. The inside of the side surface portion 20 of the fixture 16 substantially abuts on the end surface 18 of the frame 1, and the overhang 25 abuts on the bottom surface of the lens portion 2 located near the end surface 18 of the frame 1. The protruding portion 24a of the bottom 24 is in contact with the side surfaces of the grooves 6, 7. Thus, the fixing member 16 is attached to the lens portion 2.
Is fitted in the gap between the bottom surface of the substrate and the substrate 12, and is provided so as to close the gap.

The fixture 17 is made of, for example, a molded product of a polycarbonate resin, and has a side surface 28 and walls 29, 30, 31.
, A bottom portion 32, an overhang portion 33, and an engagement portion, that is, a projection portion 34. The side surface portion 28 is connected to the bottom portion 32 and is formed substantially at right angles to the bottom portion 32, and the wall portions 29, 30, and 31 are connected to the side surface portion 28 and connected to the bottom portion 32, and are formed such that the height decreases toward the tip. ing. Projection 3
Numeral 4 is formed in a substantially cylindrical shape in the vicinity of the tip of the bottom portion 32 toward the lower side. The overhang portion 33 is formed above the wall portion 30 so as to be connected to the middle wall portion 30 and to be substantially horizontal. The protruding portions 35 and 36 are formed so as to slightly protrude outside the wall portions 29 and 31, respectively.

The bottom 32 of the fixture 17 is located on the substrate 12, and the projection 34 is fitted into an engaging portion of the substrate 12, that is, a through hole 37. The inside of the side surface portion 28 of the fixture 17 substantially abuts on the end face 19 of the frame 1, and the overhang 33 contacts the bottom surface of the lens portion 2 located near the end face 19 of the frame 1. The projections 35 and 36 of the walls 29 and 31 are in contact with the reflection surfaces 4 and 5, respectively. In this manner, the fixture 17 is fitted in the gap between the bottom surface of the lens unit 2 and the substrate 12, and is provided so as to close the gap. The above-described members constitute the linear light source of the present embodiment.

[0018]

As described above, according to the present invention, the bottom of the fixture is placed on the substrate, the overhang of the fixture is brought into contact with the bottom of the lens, and the fixture is inserted into the gap between the substrate and the lens. Fit. And since the engaging part of the fixture and the engaging part of the substrate are fitted,
Fixation of the fixture is sufficiently ensured, and there is no possibility that the fixture will come off.

When the width of the substrate is made smaller than the groove in order to make it easier to insert the substrate into the groove of the frame, the protrusion formed on the wall of the fixture is attached to the side surface or the reflection surface of the groove. By making contact, the fixture and the substrate do not shift in the lateral direction. Therefore, there is no lateral displacement between the light emitting diode and the lens.

In order to fix the substrate, it is sufficient to insert the substrate into the groove of the frame, and it is not necessary to perform the heat welding as in the prior art, so that the operation of fixing the substrate and the frame becomes easy.

More preferably, the distance between the substrate and the lens portion does not change even if the substrate warps due to heat generation or the like by contacting the electric parts on the substrate with the lens portion. Therefore, the distance between the light emitting diode and the lens unit on the substrate is kept constant, and the illuminance unevenness on the light receiving surface located above the lens unit is reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view of a linear light source according to an embodiment of the present invention.

FIG. 2 is a partially exploded perspective view of a portion A in FIG.

FIG. 3 is a sectional view taken along the line BB of FIG. 1;

FIG. 4 is a partially exploded perspective view of a portion B in FIG. 1;

FIG. 5 is a sectional view taken along the line DD in FIG. 1;

FIG. 6 is a sectional view of a conventional linear light source.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Frame 2 Lens part 6, 7 Groove 12 Substrate 14 Light emitting diode 15 Electric component 16, 17 Fixture 26, 27, 34, 37 Engaging part

────────────────────────────────────────────────── (5) References JP-A-3-136456 (JP, A) JP-A-60-230626 (JP, A) JP-A-2-37784 (JP, A) (58) Survey Field (Int.Cl. ⁷ , DB name) G03B 27/54 B41J 2/44 B41J 2/45 B41J 2/455 H04N 1/04 101

Claims (2)

(57) [Claims] 1. A frame body in which a lower portion is opened and a groove is formed in a longitudinal direction of both inner side surfaces having a substantially U-shaped cross section, a long substrate housed substantially in close contact with the groove, A plurality of light-emitting diodes mounted on the substrate in a longitudinal direction, and a fixture substantially in contact with an end surface of the frame and disposed on the substrate, wherein the frame is located above the light-emitting diodes. The fixing tool is fitted in a gap between the bottom surface of the lens unit and the substrate, and the engaging portion formed on the fixing device is engaged with the engaging portion formed on the substrate. A linear light source characterized by being fitted. 2. The linear light source according to claim 1, wherein an electric component is mounted on the substrate so as to be in contact with a bottom surface of the lens unit.