JP4507495B2 - Image reader - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image reading apparatus commonly called a scanner.
[0002]
[Prior art]
A conventional image reading apparatus will be described with reference to FIG. In this image reading apparatus, a short box-shaped cabinet 1 as an outer shell is provided with a transparent glass 2 on its upper surface, and an image sensor unit (CCD unit) 3 is provided inside the cabinet 1. Yes. This image pickup device unit 3 accommodates an image pickup device (CCD) 32, a plurality of mirrors 33, 34, 35, and 36 as optical components and a condensing lens 37 inside a sealed box-shaped casing 31. Let me. Further, the housing 31 of the image pickup device unit 3 includes a box-shaped case 41 having an open upper surface and a cover 42 that closes an opening on the upper surface of the case 41, and is placed on the glass 2 on the cover 42. A light source 43 formed of a fluorescent tube that irradiates the original 100 and a light passage port 44 that guides reflected light of the original 100 to the inside of the image sensor unit 3 are provided. Further, the case 41 of the housing 31 is provided with a guide hole (not shown) through which a guide shaft 5 that guides the traveling of the housing 31 when scanning the image of the document 100 is slidably inserted.
[0003]
In the conventional image reading apparatus configured as described above, the case 41 forming the casing 31 of the image sensor unit 3 is provided with a guide hole portion through which the guide shaft 5 is slidably inserted. During 100 scans, the image sensor unit 3 travels while being guided by the guide shaft 5. Even if external light enters the interior of the cabinet 1 through the glass 2, the cover 42 of the housing 31 blocks the external light, so that external light does not enter the image sensor unit 3. The image reading performance by 32 is kept good. In FIG. 3, the alternate long and short dash line indicates the optical path of the reflected light.
[0004]
On the other hand, as a preceding example, there is disclosed a document reading apparatus that can adjust the angle of one mirror of a group of reflecting mirrors as optical components when the reflected light of a document is guided to an image sensor. (For example, refer to Patent Document 1). As another prior example, a technique for making the optical path length from the document surface to the image sensor constant during document scanning in a portable scanner reading device is disclosed (for example, see Patent Document 2).
[0005]
[Patent Document 1]
Japanese Utility Model Publication No. 7-16457 [Patent Document 2]
Japanese Patent Laid-Open No. 10-248002 [0006]
[Problems to be solved by the invention]
In the conventional image reading apparatus described with reference to FIG. 3, a case 41 in which the housing 31 is opened upward is provided for providing the housing 31 of the imaging element unit 3 with a guide hole portion through which the guide shaft 5 is inserted. Since the case 41 is open upward, a cover 42 that closes the opening of the case 41 is attached for the purpose of preventing external light from entering the image sensor unit 3. .
[0007]
However, when the casing 31 of the image pickup device unit 3 is constituted by a case 41 opened upward as in the prior art and a cover 42 attached thereto, two parts, the case 41 and the cover 42, form the casing 31. Therefore, this has been an obstacle to reducing the number of parts and reducing the cost.
[0008]
In this regard, Patent Document 1 and Patent Document 2 as prior examples do not describe how the housing of the image sensor unit is configured to achieve running stability during document scanning. There is no description about how the housing of the image sensor unit is configured to prevent the entry of external light into the image sensor unit.
[0009]
The present invention has been made in view of the above situation, and it is possible to ensure the running stability of the image sensor unit during document scanning while the housing of the image sensor unit can be configured with one component. Another object of the present invention is to provide an image reading apparatus capable of preventing a situation in which external light enters the inside of the image sensor unit and the image reading performance of the image sensor deteriorates.
[0010]
[Means for Solving the Problems]
An image reading apparatus according to the present invention optically scans an image of a document placed on a glass provided in a cabinet as an outer shell of the image reading apparatus from the lower side of the glass in the cabinet. An image sensor unit that reads the reflected image by the image sensor, and the image sensor unit includes a housing, the image sensor housed in the housing, and an optical component that guides reflected light of the document to the image sensor. ing. And the said housing | casing is equipped with the upper board part which intercepts the external light which passed through the said glass and entered into the inside of a cabinet, and the side board part lowered | hanged from the whole periphery of the upper board part, and it is opened downward. In addition, a light source composed of a fluorescent tube that irradiates the original is attached to the outer side of the upper plate portion, and light that guides the reflected light to the optical component of the image sensor unit in the vicinity of the light source mounting location. A synthetic resin is integrally formed . The optical component includes a mirror group that reflects the reflected light and a lens that collects the reflected light of the original reflected by the mirror group and guides the reflected light to the image sensor. The rear end portion of the casing made of a body is formed as a cylindrical frame portion, and the wiring substrate on which the imaging element is mounted is attached to the rear end of the frame portion, so that the rear end opening of the frame portion is the wiring When it is blocked by the substrate In the imaging element is accommodated in the housing, the protruding portion is equipped with a guide hole on the left and right sides of the frame portions, on their respective guide holes, the travel of the housing when the scanning of the original image A guide shaft for guiding is slidably inserted.
[0011]
Here, the case having the upper plate portion and the side plate portion and opening downward omits the case 41 of the case 31 of the conventional image pickup device unit 3 described in FIG. It can be thought of as a hollow covering member that opens downward by extending the peripheral edge of the cover 42, in which case the cover 42 in FIG. 3 corresponds to the upper plate portion. The portion extending downward from the peripheral edge of the cover 42 corresponds to the side plate. In addition, the housing provided with the upper plate portion and the side plate portion and opened downward omits the cover 42 of the housing 31 of the conventional image sensor unit 3 described with reference to FIG. It can also be thought of as 41 deployed upside down.
[0012]
According to the image reading apparatus configured as described above, the upper plate portion of the housing of the image pickup device unit and the side plate portion that is lowered from the entire periphery of the upper plate portion block external light. A situation in which external light enters and the image reading performance of the image sensor deteriorates does not occur. In addition, since the housing is provided with an upper plate portion and a side plate portion and is opened downward, only one component is required for the housing. Therefore, cost reduction by reducing the number of parts can be easily promoted.
[0013]
In the present invention, the housing formed of a synthetic resin integral molded body has a cylindrical frame portion at the rear end portion thereof, and a wiring board on which the image pickup device is mounted is attached to the rear end portion of the frame portion, thereby the image pickup device. Are housed in the housing, and are provided with protrusions having guide hole portions on both the left and right sides of the frame portion, and each of the guide hole portions allows the housing to travel when scanning an image of a document. A guide shaft for guiding is slidably inserted. With this configuration, the running stability of the image sensor unit during document scanning is ensured by the cooperation of the guide hole portion of the housing and the guide shaft.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a longitudinal side view schematically illustrating the overall configuration of an image reading apparatus according to the present invention, and FIG. 2 is a perspective view schematically illustrating a housing of an image sensor unit.
[0015]
In FIG. 1, reference numeral 1 denotes a box-shaped cabinet as an outer shell of an image reading apparatus, which has a glass 2 on its upper surface, and a document 100 is placed on the glass 2 during document scanning. A guide shaft 5 is horizontally disposed inside the cabinet 1, and traveling of the image sensor unit 3 housed in the cabinet 1 is guided by the guide shaft 5. The image sensor unit 3 accommodates an image sensor 32, mirrors 33, 34, 35, and 36 as optical components and a condensing lens 37 inside a casing 61 having a downward opening 62.
[0016]
As can be seen from FIG. 1 and FIG. 2, the housing 61 of the image sensor unit 3 includes an upper plate portion 63 and a side plate portion 64 that is lowered from the entire periphery of the upper plate portion 63. In addition, the rear end portion is formed as a cylindrical frame portion 65. The casing 61 is made of a synthetic resin integral molding. Moreover, the protrusion part 66 provided with the guide hole part 67 is provided in the right and left both sides of the frame part 65, and the guide shaft 5 is slidably inserted in the guide hole part 67. Therefore, the running stability of the image sensor unit 3 during document scanning is ensured by the cooperation of the guide hole 67 of the protrusion 66 and the guide shaft 5 inserted therethrough. Further, a light source 43 made of a fluorescent tube is attached to the outside of the upper plate portion 63 of the housing 61, and a light passage port 44 is provided in the vicinity of the place where the light source 43 is attached.
[0017]
As shown in FIG. 2, the image pickup device 32 is mounted on the wiring board 7, and is attached to a predetermined position of the housing 61 by attaching the wiring board 7 to the rear end of the frame portion 65 of the housing 61. In a state where the wiring substrate 7 is attached to the rear end of the frame portion 65 of the housing 61, the rear end opening of the frame portion 65 is blocked by the wiring substrate 7 and the imaging element 32 is accommodated in the housing 61. ing.
[0018]
According to this image reading apparatus, although the casing 61 is composed of a single component, the running stability of the image sensor unit 3 during document scanning as described above is such that the guide hole 67 of the protrusion 66 is provided. And the guide shaft 5 inserted therethrough, and even if external light enters the cabinet 5 through the glass 2, the upper plate portion 63 and the side plate portion of the housing 61 of the image sensor unit 3 Since the external light 64 blocks the outside light, it was confirmed that the external light enters the inside of the image pickup device unit 3 and the image reading performance by the image pickup device 32 is kept good.
[0019]
When the image reading apparatus reads an image of the document 100, the image pickup device unit 3 is moved in the direction of arrow A in FIG. 1 with the document 100 placed on the glass 2. As a result, the original image of the portion irradiated with light from the light source 43 is optically scanned from the lower side of the glass 2, and the reflected light of the original image is reflected by the mirrors 33, 34, 35, 36, the lens 37, and the like. The image is read by being guided to the image sensor 32 via the optical components. In FIG. 1, the alternate long and short dash line indicates the optical path of the reflected light.
[0020]
In the image reading apparatus of this embodiment, the housing 61 of the image sensor unit 3 is arranged by inverting the case 41 of the housing 3 of the conventional example described in FIG. Since it can be considered that the light source 43 and the light passage port 44 are provided on the upper plate portion 63 of the housing 61, in this case, the cover 42 of the conventional example becomes unnecessary. Further, the casing 61 is formed by omitting the case 41 of the casing 31 of the conventional image sensor unit 3 described with reference to FIG. 3 and instead extending the peripheral edge of the cover 42 downward. 3, in which case the cover 42 in FIG. 3 corresponds to the upper plate portion and extends downward from the peripheral portion of the cover 42. Since the portion corresponds to the side plate portion, the case 41 of FIG. 3 is not necessary.
[0021]
In the description of the embodiment, the same reference numerals are given to the portions corresponding to the portions described in FIG.
[0022]
【The invention's effect】
As described above, according to the present invention, while the housing of the image sensor unit is configured with one component, the running stability of the image sensor unit during document scanning is ensured, and at the same time, the image sensor unit is provided inside the image sensor unit. It is possible to provide an image reading apparatus that does not cause a situation in which external light enters and the image reading performance of the image pickup device deteriorates.
[Brief description of the drawings]
FIG. 1 is a longitudinal side view schematically showing the overall configuration of an image reading apparatus according to the present invention.
FIG. 2 is a perspective view schematically showing a housing of an image sensor unit.
FIG. 3 is a longitudinal side view schematically showing a main part of a conventional image reading apparatus.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Cabinet 2 Glass 3 Image pick-up element unit 5 Guide shaft 32 Image pick-up element 33, 34, 35, 36 Mirror 37 Lens 44 Light passage 61 Case 62 Opening 63 Upper plate part 64 Side plate part 67 Guide hole part

Claims (1)

An image of a document placed on a glass provided in a cabinet as an outer shell of the image reading device is optically scanned from the lower side of the glass in the cabinet, and a reflected image thereof is read by an image sensor. In an image reading apparatus including an image sensor unit, the image sensor unit including a housing, the image sensor housed in the housing, and an optical component that guides reflected light of a document to the image sensor.
The housing includes an upper plate portion that blocks outside light that passes through the glass and enters the inside of the cabinet, and a side plate portion that is lowered from the entire periphery of the upper plate portion, and opens downward. The upper plate portion is provided with a light source composed of a fluorescent tube for irradiating a document on the outside thereof, and a light passage opening for guiding the reflected light to an optical component of the image pickup device unit in the vicinity of the light source mounting portion. With
The optical component includes a mirror group that reflects the reflected light and a lens that collects the reflected light of the document reflected by the mirror group and guides the reflected light to the image sensor,
A rear end portion of the casing made of a synthetic resin integral body is formed as a cylindrical frame portion, and a wiring board on which the imaging element is mounted is attached to the rear end of the frame portion. The end opening is closed by the wiring board and the imaging element is housed in the housing, and the left and right sides of the frame are provided with protrusions having guide holes, and each of the guide holes is provided. An image reading apparatus, wherein a guide shaft for guiding the travel of the casing during scanning of an image of a document is slidably inserted.

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