JP2000115457A - Image sensor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the cloudiness or damage of a read window, to prolong the service life of the read window and to improve workability in the case of exchanging the read windows by protruding a bank part in the vertical direction from a window surface toward an outward position of a window part so that a read medium becomes in noncontact with the window surface of the window part. SOLUTION: An image sensor 1 is constituted of a guide block 2 and a casing 3. The guide block 2 is detachably fixed to the casing 3 with a screw. An upper surface of the guide block 2 has a step structure (a height) composed of a flat surface and a back part 13. The bank part 13 is formed in a comb- teeth shape in an outward direction with a window part 14 as a center. Also, an edge part face 19 of this bank part 13 is finished on a slope having a specified inclination in the vertical direction. Since due to the height (h) of the bank part 13, a distance from the window part 14 to a read medium 12 is kept constant and reading is made possible without the read medium 12 directly touching the window part 14, the cloudiness or damage of the surface of the window part can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technology effective when applied to an image sensor for reading characters and marks printed on paper or a plastic sheet.

[0002]

2. Description of the Related Art Conventionally, in an image sensor for reading a mark sheet or the like of this type, in order to keep a distance between a CCD and the surface of a reading sheet constant, a plate glass is interposed as a reading window, and the surface of the mark sheet is placed on the plate glass. In general, the marking state on the surface of the mark sheet is read while the mark sheet is conveyed by a pressure roller while being in contact with the mark sheet.

However, in the structure of such an image sensor, the mark sheet is repeatedly conveyed in a contact state while directly pressing the mark sheet against the surface of the plate glass, so that the glass surface gradually becomes rough due to friction with the mark sheet surface. White turbidity and scratches occurred, which affected reading accuracy.

Furthermore, since the glass sheet is adhered to the main body of the image sensor, there is a problem that the workability of replacing the glass body alone is poor. Also, when performing the exchange,
Since the entire sheet glass also functions as a conveyance guide for the mark sheet, there is a problem that it is difficult to align the position with the conveyance guide provided before and after the image sensor.

[0005] The present invention has been made in view of the above points, and prevents the reading window from becoming cloudy or damaged, extending the life of the reading window, and improving the workability when replacing the reading window. An object of the present invention is to provide a very good image sensor technology.

[0006]

According to the present invention, there is provided an image sensor device for reading, by an optical element, a character, a symbol or a figure printed or written on a reading medium through a window. A structure is provided that includes a bank portion protruding vertically from a window surface at a position outside the window portion so that the medium is not in contact with the medium (corresponding to claim 1).

The height of the bank keeps the distance of the reading medium from the window constant, so that the reading can be performed without the reading medium coming into direct contact with the window. Cloudiness and damage can be prevented.

Further, by forming the bank portion in a comb-like shape outside the window portion, the bank portion can function as a guide for receiving and transferring the reading medium to the image sensor device. Corresponding to).

Further, at this time, if the leading end of the transport guide formed into a concave-convex shape corresponding to the comb teeth as viewed from the plane is inserted into the comb-shaped space, the transport of the reading medium is performed. Transfer from the guide to the bank can be performed smoothly. Further, if the leading end of the transport guide is bent in the direction in which the bank portion does not protrude, it is possible to prevent the transport guide from being caught at the bank portion at the bank portion during transport.

A pressure roller for pressing and transporting the reading medium on the window portion is provided vertically above the window portion, and the pressure roller has a larger diameter at both ends in the axial direction than the pressure roller. A configuration is provided with a roller guide, and a part of the bank portion is brought into sliding contact with the peripheral surface of the roller guide (abutting portion). Thus, the position of the pressure roller on the window is defined (corresponding to claim 3).

The window and the bank are integrally formed as a guide block with a transparent resin. This allows
A guide block that can be attached to and detached from the casing can be obtained by integral molding, so that productivity and maintainability of the image sensor device can be improved (corresponding to claim 4).

Further, the window portion may be formed separately from the guide block by a glass plate or the like as in the prior art. In this case, the selectivity of the material of the guide block can be expanded (corresponding to claim 5).

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

[0014]

Embodiment 1 FIG. 1 is a diagram showing a sectional structure of an image sensor according to an embodiment of the present invention, and FIG. 2 is a plan view thereof.

The image sensor 1 of the present embodiment is a so-called contact type image sensor, in which a signal is read in close contact with a medium on which a mark, a character, a symbol, a bar code or the like is printed.

The image sensor 1 comprises a guide block 2 and a casing 3. Guide block 2
Is detachably fixed to the casing 3 with screws 5.

The upper surface of the guide block 2 of the present embodiment has a step structure (height h) composed of a flat surface 9 and a bank portion 13. As shown in FIG. 2, the bank portion 13 is formed in a comb-like shape with the window portion 14 at the center and outward. The end surface 19 of the bank 13 is formed into a slope having a certain inclination with respect to the vertical direction.

Further, both ends in the longitudinal direction of the window portion 14 of the bank portion 13 function as abutting portions 21 of a roller guide 23 of a pressure roller 22 described later. Here, the height of the abutting portion 21 is the same as the height h of the other bank portions 13, but by adjusting the height of the abutting portion 21 at the time of machining the guide block 2 or after the past, The degree of pressure of the pressure roller 22 can be changed.

The pressure roller 22 is made of synthetic rubber or synthetic resin having elasticity, and the roller guide 23 is made of hard synthetic resin or metal. In this embodiment, in the guide block 2 described above, both the flat surface 9 and the bank portion 13 are integrally formed of a hard transparent resin such as polycarbonate.

On the other hand, the casing 3 is made of a metal or a synthetic resin, and is obtained through an extrusion molding of an aluminum alloy or the like or a resin molding process. This casing 3
A lens unit 7 is disposed at a position directly below the window portion 14, and a light source unit 6 is mounted outside the lens unit 7. The light source unit 6 is constituted by a light emitting diode array or the like, and irradiates the window 14 from obliquely below the window 14.

Further below the lens unit 7,
The CCD 8 attached to the printed wiring board 10 is attached, and the mark state of the mark sheet 12 passing just above the window 14 is read based on the difference in reflected light of the light source unit 6.

An external connector 11 is provided below the side of the casing 3 so as to output a signal from the CCD 8 to the outside and to supply a driving power to the light source unit 6 and the printed wiring board 10 from the outside. It has become.

A pressure roller 22 is disposed above the window 14. A roller guide 23 having a larger diameter than the pressure roller 22 is provided at an axial end of the pressure roller 22. The pressure roller 22 rotates while the peripheral surface of the roller guide 23 is in sliding contact with the abutting portion 21 of the bank portion 13 (see FIGS. 1 and 8).

FIGS. 3 and 4 show a state in which the conveyance guide 15 is arranged with respect to the image sensor 1 of this embodiment. As shown in FIG. 4, the transport guide 15 is formed by processing one end of a plate material made of a stainless alloy into an uneven surface, and the protrusion 16 enters the flat surface 9 of the guide block 2. The position is aligned with the image sensor 1 so that the bank portion 13 of the block 2 enters.

Further, the tip of the transfer guide 15 (the protrusion 1
7) is bent slightly obliquely downward, that is, in the direction in which the bank portion 13 does not protrude, so that the mark sheet 12 conveyed on the conveyance guide surface is smoothly (without being caught) at the end of the bank portion 13. It is configured to be delivered from the outer surface 19 to the upper surface of the bank 13.

That is, the mark sheet 12 sent from the left to the right in FIG. 1 on the transport guide 15 passes over the bank portion 13 of the guide block 2 and is pressed by the pressure roller 22 into the window portion. 14 at a constant speed. At this time, the mark sheet 12 is moved by the height h of the bank portion 13 while maintaining a non-contact state with the window surface of the window portion 14.

During this movement, the mark sheet 12
A mark printed or written on one surface (the lower surface in FIG. 1) is emitted from the light source unit 6 through the window 14. The reflected light of the irradiation light is read by the CCD 8 through the lens unit 7 from the window 14.

As described above, according to the present embodiment, since the mark sheet 12 is allowed to pass through the bank portion 13 of the guide block 2 in a non-contact state with the window surface of the window portion 14, the window portion 14 is provided.
Can be prevented from being damaged or clouded due to contact with the mark sheet 12.

The guide block 2 having the window 14
Is attached to the casing 3 by the screws 5, so that maintenance such as replacement of parts can be greatly improved.

In the conventional structure in which the window and the guide are separate bodies, there is a possibility that foreign matter such as dust may enter the gap at the boundary between the window and the guide. Then, since this is an integral structure, there is no fear of this.

[0031]

Embodiment 2 FIG. 5 is a sectional view showing another embodiment of the present invention. The second embodiment differs from the first embodiment in the configuration of the guide block 51. That is, in the second embodiment, the transparent plate glass 52 is attached to the window portion 14 of the first embodiment, and the plate glass 52 substantially constitutes the window. The upper surface of the plate glass 52 is disposed at a position lower than the bank 13 of the guide block 51.

As described above, also in the second embodiment, since the upper surface of the plate glass 52 constituting the window portion is at a position lower than the bank portion 13, the mark sheet 12 is
Since it does not come into direct contact with 2, the surface of the plate glass 52 due to friction can be prevented from being clouded or damaged due to friction.

Further, in the second embodiment, since the plate glass 52 forming the window is formed separately from the guide block 2, the guide block 2 may be formed of an opaque synthetic resin. The nature increases.

[0034]

Embodiment 3 FIG. 6 is a sectional view showing another embodiment of the present invention. The third embodiment is characterized by a structure for mounting the guide block 63 and the casing 64. In the first and second embodiments, the guide block 2 is fixed to the casing 3 with the screws 5, but the third embodiment has a fitting structure.

The structure of the upper surface of the guide block 63 is the same as that of the first or second embodiment.
A skirt 65 extends downward from the outer sides of both sides of the skirt 65, and a fitting claw 62 is formed at the lower inner end of the skirt 65 so as to project therefrom.

The fitting claws 62 are provided so as to fit into fitting grooves 61 provided above both side surfaces of the casing 64. In the third embodiment, when the guide block 63 is attached to the casing 64,
The guide block 63 only needs to be pushed in from above and inserted.

When the guide block 63 is removed from the casing 64, the two skirts 65 of the guide block 63 are expanded in the direction away from each other to release the fitting state of the fitting claw 62 and the fitting groove 61. Guide block 6
3 may be pulled upward.

As a method for removing the guide block 63 from the casing 64, the fitting claw 62 is
The guide block 63 may be removed by sliding the guide block 63 backward or forward along the plane of FIG.

[0039]

Embodiment 4 FIG. 7 also shows a guide block 73 and a casing 7.
4 is characterized by its mounting structure. In the fourth embodiment, the skirt 75 extends downward from the outer sides on both sides of the guide block 73.
The skirt 75 is provided with a projection 72 at the lower inner end thereof.

The projections 72 are provided so as to fit into the fitting grooves 61 provided above both side surfaces of the casing 74. In the fourth embodiment, when the guide block 73 is attached to the casing 74, the casing 74
The projection 72 is slid into the fitting groove 71 from the end in the longitudinal direction.

When the guide block 73 is detached from the casing 74, the protrusion 72 is moved along the fitting groove 71 rearward or forward of the paper of FIG.
Can be removed by sliding.

[0042]

According to the present invention, since the window surface is arranged at a position lower than the bank portion, reading can be performed in a state where the mark sheet and the window portion are not in contact with each other. Turbidity and damage due to wear can be prevented.

[Brief description of the drawings]

FIG. 1 is a front sectional view of an image sensor according to an embodiment of the present invention.

FIG. 2 is a plan view of the image sensor according to the embodiment.

FIG. 3 is a front view showing a positional relationship between the image sensor and the transport guide according to the embodiment.

FIG. 4 is a plan view showing a positional relationship between an image sensor and a transport guide according to the embodiment.

FIG. 5 is a front sectional view of the image sensor according to the second embodiment.

FIG. 6 is a front sectional view of an image sensor according to a third embodiment.

FIG. 7 is a front sectional view of an image sensor according to a fourth embodiment.

FIG. 8 is a side view showing an arrangement relationship between an image sensor and a pressure roller in the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image sensor 2 Guide block 3 Casing 5 Screw 6 Light source unit 7 Lens unit 8 CCD 9 Flat surface 10 Printed wiring board 11 Connector 12 Mark sheet 13 Bank part 14 Window 15 Transport guide 16 Projection 17 Depression 19 End face 21 Abutment Part 22 Pressure roller 23 Roller guide 51 Guide block 52 Sheet glass 61 Fitting groove 62 Fitting claw 63 Guide block 64 Casing 65 Skirt 73 Guide block 74 Casing 75 Skirt

Continuing on the front page (72) Inventor Jinichi Nakamura 4-1-1, Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Prefecture Inside Fujitsu Limited (72) Inventor Haruyuki Fujimoto 1776 Yanoguchi, Inagi-shi, Tokyo Fujitsu Kiden Corporation ( 72) Inventor Kazushima Kazushima 1776 Yanoguchi, Inagi-shi, Tokyo FUJITSU DENKI CO., LTD.F-term (reference)

Claims (5)

[Claims] 1. An image sensor device for reading, by an optical element, characters, symbols, or graphics printed or written on a reading medium through a window, wherein the reading medium is not in contact with a window surface of the window. An image sensor device having a bank portion protruding vertically from a window surface at a position outside the window portion. 2. The bank portion has a planar shape formed in a comb shape outside the window portion.
An image sensor device according to claim 1. 3. A pressure roller for pressing and transporting the reading medium on the window is disposed above the window, and the pressure roller is provided at both ends in the axial direction thereof with respect to the pressure roller. A roller guide having a large diameter is provided, and a part of the bank portion serves as an abutting portion to contact the peripheral surface of the roller guide to define the position of the pressure roller on the window portion. The image sensor device according to claim 1. 4. The image sensor device according to claim 1, wherein said window portion and said bank portion are integrally formed as a guide block by a light transmitting resin. 5. The apparatus according to claim 1, wherein the window is attached to a guide block having a bank.
An image sensor device according to claim 1.