JP2562053B2 - Image reader - Google Patents

Description

The present invention relates to an image reading apparatus used in, for example, a digital copying machine, a facsimile, an input device of a computer, or the like.

(Prior Art) As a conventional image reading apparatus of this type, for example,
There is something like the one shown in the figure. That is, this device is a light source
An optical image of the original 101 illuminated by 100 is formed on the reading sensor 103 via the short focus lens array 102 to read the image. The light source 100, the lens array 102, the reading sensor 103, and the electric components 104 such as capacitors and transistors attached to the reading sensor 103 are attached to one moving carriage 105. By moving the moving carriage 105, The document surface is read and scanned.

The light source 100 illuminates the reading portion of the original 101, which is arranged beside the lens array 102 and effectively illuminates the reading portion of the original using the reflection shade 106. On the other hand, the electric components 104 attached to the reading sensor 103 are also arranged on the same side as the light source 100 with respect to the lens array 102, and are collectively provided below the light source 100.

(Problems to be Solved by the Invention) However, in the case of the above-described conventional technique, the light source 100
Since the electric component 104 and the electric component 104 are provided on the same side with respect to the lens array 102, the radiant heat h acts on the electric component 104 from the reflection shade 106 that has been heated by the heat generation of the light source 100, and
There was a risk that 104 would exceed the guaranteed temperature (for example, 85 ° C for a capacitor) and would not operate normally. Therefore, it is necessary to insulate the radiant heat by the heat insulating member so that it does not reach the electric component 104, but there is a problem that the device configuration becomes larger and the cost increases accordingly.

In particular, since such a reading sensor 103 requires a certain amount of light, a halogen lamp is usually used as the light source 100. Here, when a miniature bulb type halogen lamp is used as in the illustrated example, a hole 107 through which the lamp leg is passed is required in the reflection shade 106 due to the configuration, and the illumination light leaks from this hole 107 to the electric component 104. It hits directly and promotes the temperature rise.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object thereof is to provide an image reading apparatus having high reliability by preventing the influence of heat from a light source on electric parts. Especially.

(Means for Solving the Problem) In order to achieve the above object, in the present invention, a light source for illuminating a document and a reflection provided around the light source and having a hole for passing a leg of the light source. A shade, a reading sensor that receives the image light obtained from the original, an imaging lens that forms an image of the image light obtained from the original on the reading sensor, a lens holder that holds the imaging lens, and an electrical accessory attached to the reading sensor. In a component and an image reading apparatus incorporated in one moving carriage, a second reflection shade different from the reflection shade is attached to the surface of the lens holder opposite to the side where the light source is provided. The light source and the electric component are provided on opposite sides of the imaging lens so that direct light from the light source toward the electric component is blocked by the lens holder and the second reflection shade. It is characterized by the following.

(Operation) In the image reading apparatus having the above-described configuration, the second reflection shade is attached to the surface of the lens holder opposite to the side where the light source is provided, and the direct light from the light source to the electric component is directed to the lens. Since the light source and the electric component are provided on opposite sides of the imaging lens so as to be blocked by the holder and the second reflection shade, the electric component does not receive direct light from the light source,
It is possible to prevent a temperature rise due to direct light irradiation.

(Example) Below, this invention is demonstrated based on the Example shown in figure. In FIGS. 1 and 2 showing an image reading apparatus according to an embodiment of the present invention, reference numeral 11 denotes a main scanning carriage as a moving carriage having a reading sensor 7 such as a CCD, which is on a document panel 3 such as transparent glass. The original document O placed on is read and scanned.

The main scanning carriage 11 has a miniature bulb type halogen lamp 2 as a light source for illuminating the original O and a short focus lens array 1 for forming an optical image of the original O on the reading sensor 7.
It has and. The reading sensor 7 and electric components 8 such as capacitors and transistors attached to the reading sensor 7 are mounted on an electric board 9, and the reading sensor 7 is mounted on the electric board 9.
A code 10 for sending the signal read by the device to a signal processing unit, an image output unit or the like (not shown) is connected.

In the vicinity of the halogen lamp 2, there are provided a reflection shade 4A for converging the illumination light on the reading portion of the original O, a reflection shade 4B as a second reflection shade, and a shading plate 5 is unnecessary. The light of the halogen lamp 2 is prevented from leaking to the place. An infrared cut filter 6 is provided in the optical path between the reading sensor 7 and the short focus lens array 1. Further, the reflection shade 4A is provided with a hole 13 for passing the leg 2a of the halogen lamp 2 as a light source.

Here, the positions of the halogen lamp 2 and the electric components 8 of the reading sensor 7 are symmetrically arranged on the opposite sides of the short focus lens array 1. That is, the halogen lamp 2 and the electric component 8 are arranged with respect to the short focus lens array 1 in a direction (hereinafter referred to as Y axis direction) orthogonal to the longitudinal direction of the short focus lens array 1 (hereinafter referred to as X axis direction). It is placed separately on the opposite side. And halogen lamp 2
Is arranged at the same height as the end of the short focus lens array 1 on the document side, while the electric component 8 is arranged at the same height as the reading sensor 7 below the short focus lens array 1.

The short focus lens array 1 is held over the entire length in a holder portion 20 as a lens holder provided in the main scanning carriage 11, and one reflection shade 4B for a halogen lamp is at the upper end of the holder portion 20 on the electric component 8 side. The electric component 8 is attached to the rim, and the electric component 8 is the holder portion when viewed from the halogen lamp 2 side.
It is placed in such a position as to be in the shadow of 20 and the shade 4B.
The electrical component 8 includes a wall portion that shields the short-focus lens array 1 and the reading sensor 7 from outside light and a frame portion of the carriage.
It is surrounded by 11a and is structured so as not to receive the irradiation light directly.

As shown in FIGS. 3 and 4, the main scanning carriage 11 is driven in the Y-axis direction by the sub-scanning carriage 12 along the main scanning rail 11A, and the sub-scanning carriage 12 extends in the X-axis direction. The drive is controlled along the rail 12A in the X-axis direction. Then, as shown in FIG. 4, while the sub-scanning carriage 12 is stopped, the main scanning carriage 11 is moved from the point A to the point B to read a document image of a constant width by the reading sensor 7 and return to the point A.

Next, the sub scanning carriage 12 is moved in the X axis direction from point a by the width read by the reading sensor 7, and the main scanning carriage 11 is moved again from point A to point B in the Y axis direction to read the next image. . In this way, a required image is read by performing serial scanning for sequentially reading images of a constant width.

Here, the light traveling from the halogen lamp 2 toward the electric component 8 side is the holder portion 20 of the short focus lens array 11 and the reflection shade 4B.
The light from the lamp does not reach the electric component 8 either directly or indirectly. Therefore, it is possible to block the direct light from the light source that is most affected by the temperature rise of the electric component 8 and reduce the temperature rise of the electric component 8.

Further, the radiant heat h radiated from the halogen lamp 2 and the reflection shade 4A in the vicinity thereof is also insulated by the holder portion 20 of the short focus lens array 1 and does not reach the electric component 8. Therefore, the temperature rise of the electric component 8 can be reduced as much as possible.

In addition, although the miniature bulb type lamp has been described in the above embodiment, the present invention can be similarly applied to a tube type lamp having no reflector shade hole for the miniature bulb type lamp. Further, although the short focus lens array 11 has been described as an example of the imaging lens, another lens using a convex lens or the like may be used.

(Effects of the Invention) The present invention has the above-described configuration and operation, and on the surface of the lens holder opposite to the side on which the light source is provided,
Since the second reflector is attached and the light source and the electric component are provided on opposite sides of the imaging lens so that direct light traveling from the light source to the electric component is blocked by the lens holder and the second reflector, It is possible to block the direct light from the light source, which has the greatest effect on the temperature rise, and prevent the malfunction of the image reading apparatus due to the temperature rise of the electric components.

[Brief description of drawings]

1 is a longitudinal sectional view of an essential part of an image reading apparatus according to an embodiment of the present invention, FIG. 2 is a schematic perspective view of the apparatus of FIG. 1, and FIG. 3 is an image incorporating the apparatus of FIG. FIG. 4 is a schematic vertical cross-sectional view showing the overall configuration of the reading device, FIG. 4 is a schematic plan view of the device of FIG. 3, and FIG. 5 is a vertical cross-sectional view of a main part of a conventional image reading device. Explanation of reference numerals 1 ... Short focus lens array (imaging lens) 2 ... Halogen lamp (light source) 3 ... Document panel, 4A ... Reflector shade, 4B ... Reflector shade (second)
Reflector) 7 ... Reading sensor, 8 ... Electrical components 11 ... Main scanning carriage (moving carriage) 20 ... Holder (lens holder), O ... Original

Claims (1)

(57) [Claims] 1. A light source for illuminating a document, a reflector provided around the light source and having a hole for passing a leg of the light source, a reading sensor for receiving image light obtained from the document, and a reading sensor for the document. An image reading device in which an image forming lens for forming an image light of a formed image on a reading sensor, a lens holder for holding the image forming lens, and an electrical component attached to the reading sensor are incorporated in one moving carriage. A second reflection shade different from the reflection shade is attached to the surface opposite to the side where the light source is provided, and direct light from the light source to the electric component is directed to the lens holder and the lens holder. An image reading apparatus, wherein the light source and the electric component are provided on opposite sides of the imaging lens so as to be blocked by a second reflection shade.