JP2013143245A - Lighting system for image scanner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize with an LED light sources, a lighting system for an image scanner used as a light source for image scanner scanning.SOLUTION: The lighting system is provided with a strip-shaped metal illumination board 10 with a plurality of LED light sources L linearly arranged and mounted on its top surface at intervals, and a light cover 1 having translucency, incorporating the illumination board and with a light diffusion process applied. The illumination board is pinched between a bottom part 2 of the light cover and locking flanges 3, 3 set in protrusion on right and left inner walls above the bottom part 2, and also, a constant gap is set between top surfaces of the mounted LED light sources and a ceiling surface of the light cover.

Description

  The present invention relates to an illumination device for an image scanner for use as a light source for scanning of an image scanner.

  As a light source for scanning of an image scanner, a linear light source having a total length corresponding to the width to be scanned is required. For this reason, a cold cathode tube has been conventionally used as this type of light source (Patent Document 1). .

JP 2007-53716 A Design Registration No. 1347110

  In the prior art, the reason why the cold cathode tube is used is because of its compactness, thereby contributing to the downsizing of the image scanner.

  However, there is a problem that a cold cathode tube has a dependency on temperature and requires a rise time until it can be used.

  In addition, a power supply different from that for driving the scanner motor is required, which is disadvantageous in terms of cost.

  The present invention was created for the purpose of providing an illumination device for an image scanner that solves the above problems. That is, the illumination device for an image scanner according to the present invention is a strip-shaped metal illumination substrate having a plurality of LED light sources arranged on a top surface and arranged in a straight line at intervals, and a light diffusion process for interior of the illumination substrate. And the lighting board is sandwiched between a bottom portion of the light cover and a locking rod projecting on the left and right inner walls thereon, and an upper surface of the mounted LED light source A certain gap is opened between the light cover and the ceiling surface of the light cover.

  The invention described in claim 3 is characterized in that, in the illumination device for an image scanner, ventilation windows are arranged at intervals on the side wall of the light cover.

  According to a fourth aspect of the present invention, in the image scanner illumination device, a window is disposed at a bottom portion of the light cover at an interval.

  According to a fifth aspect of the present invention, in the image scanner illumination device, a central notch is provided at the bottom of the light cover in the entire length direction.

  A cold cathode tube is a linear light source, whereas an LED light source is a point light source. In this case, it is known to obtain linear light emission by mounting LED light sources on a straight line at intervals (for example, Patent Document 2).

  However, since there is a dark part between the LED light sources mounted side by side, light ripples are generated by the scattered LED light sources, and this is not a problem for normal illumination, but for scanning of image scanners. This was a problem for the light source.

  On the other hand, when it was assumed to be used as an alternative to a cold cathode tube that contributed to the miniaturization of an image scanner, it had to be the same size as or smaller than the cold cathode tube. In that case, the LED light source has a property of generating high heat when trying to obtain a high illumination luminance, so that the problem has to be solved.

  In the illumination device for an image scanner according to the present invention, the light cover is first subjected to a light diffusion process, and a certain gap is provided between the upper surface of the LED light source mounted at the same time and the ceiling surface of the light cover. Thus, the light from the scattered LED light sources is diffused in the process of passing through the light cover to prevent the light ripple.

  In addition, a strip-shaped metal lighting board having a plurality of LED light sources arranged and mounted on the upper surface in a straight line is spaced between the bottom of the light cover and the locking rods protruding from the left and right inner walls. By sandwiching the light cover, the lighting board will skew the light cover with both ends open. In addition to exhausting the heat accumulated inside the light cover through the gap between the light covers, The metal lighting board exposed from both ends of the cover also serves as a radiator that releases the heat accumulated inside, and prevents the temperature inside the lighting device from increasing when the illumination brightness is increased.

  In addition, since the lighting board is inserted into the light cover with both ends open, the light cover does not require an opening / closing part, contributing to downsizing, and the light cover can be obtained by extrusion molding, which is advantageous in terms of cost. .

  Further, by using the LED light source, the power source can be shared with that for driving the scanner motor, which is advantageous in terms of cost.

The disassembled perspective view of the illuminating device for image scanners of this invention. The top view of the illuminating device for image scanners of this invention. Same as above, bottom view. Same as above, side view. FIG. FIG. Sectional drawing of the lamp cover of the illuminating device for image scanners of this invention. The perspective view of the Example from which the lamp cover of the illuminating device for image scanners of this invention differs. The bottom view of the Example from which the lamp cover of the illuminating device for image scanners of this invention differs. The perspective view of the Example from which the lamp cover of the illuminating device for image scanners of this invention differs.

  Hereinafter, specific embodiments of the illumination device for an image scanner according to the present invention will be described with reference to the accompanying drawings. The illumination device for an image scanner according to the present invention includes an illumination substrate 10 and a light cover 1 that houses the illumination substrate. The illumination board 10 is made of a strip-shaped metal plate on which a plurality of LED light sources L are arranged in a straight line at intervals, and an aluminum plate is used here.

  The light cover 1 in which the illumination board 10 is housed sandwiches the illumination board 4 between the bottom part 2 of the light cover and the locking rods 3 and 3 projecting from the left and right inner walls thereon, The lighting board will skew the light cover open at both ends. Screw holes 11 and 11 for setting screws for attaching the illumination device to the scanner are formed at both ends of the illumination board exposed from both ends of the light cover. A connection terminal connector C for energizing the LED light source L is mounted on one end of the exposed illumination board. In addition, although the said locking rods 3 and 3 have illustrated the linear thing continuous in the full length direction of the light cover 1 here, of course, you may divide | segment into plurality.

  The light cover 1 has a light-transmitting property subjected to a light diffusion treatment, and is obtained by extrusion molding with a synthetic resin. In this case, polycarbonate is most suitable as a synthetic resin from the viewpoint of rigidity, heat resistance, and flame retardancy.

  FIG. 6 is a diagram showing a cross section of the lighting device. A certain gap is opened between the upper surface of the mounted LED light source L and the ceiling surface 4 of the light cover 1, thereby diffusing light by the light cover. The effect is enhanced, and light ripples are prevented from being generated by the scattered LED light sources.

  FIG. 8 is a view showing a different embodiment of the light cover 1, and here, exhaust air from the light cover is intended by arranging ventilation windows M <b> 1 on the side walls of the light cover 1 at intervals.

  FIG. 9 is a diagram showing a different embodiment of the light cover 1. Here, by arranging a window M 2 at a distance from the bottom 2 of the light cover 1, the heat accumulated in the metal illumination board is stored inside. We aim to promote the role of a radiator to escape the outside.

  FIG. 10 is a view showing a different embodiment of the light cover 1, in which a metal illumination board is accumulated inside by providing a K at the bottom 2 of the light cover 1 along the entire length direction. It is intended to promote the role of a radiator that escapes heat.

1 Light cover 10 Lighting board
L LED light source

The light cover 1 in which the illumination board 10 is housed sandwiches the illumination board 10 between the bottom portion 2 of the light cover and the locking rods 3 and 3 protruding on the left and right inner walls. The lighting board will skew the light cover open at both ends. Screw holes 11 and 11 for setting screws for attaching the illumination device to the scanner are formed at both ends of the illumination board exposed from both ends of the light cover. A connection terminal connector C for energizing the LED light source L is mounted on one end of the exposed illumination board. In addition, although the said locking rods 3 and 3 have illustrated the linear thing continuous in the full length direction of the light cover 1 here, of course, you may divide | segment into plurality.

Claims (5)

  It consists of a strip-shaped metal lighting board on which a plurality of LED light sources are mounted in a straight line at intervals on the upper surface, and a light cover with translucency that has been subjected to a light diffusing process that interiors the lighting board. The lighting board is sandwiched between the bottom portion of the light cover and a locking rod protruding from the left and right inner walls, and between the upper surface of the mounted LED light source and the ceiling surface of the light cover. An illumination device for an image scanner, wherein a certain gap is opened.   The illumination device for an image scanner according to claim 1, wherein the light cover is obtained by extruding polycarbonate.   The illumination device for an image scanner according to claim 1, wherein ventilation windows are arranged at intervals on a side wall of the light cover.   The illumination device for an image scanner according to any one of claims 1 to 3, wherein windows are arranged at intervals on a bottom portion of the light cover.   The illumination device for an image scanner according to any one of claims 1 to 4, wherein a bottom portion of the light cover is provided with a central cutout in the entire length direction.

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