JP3624105B2 - Image sensor device - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
The present invention relates to a technique effective when applied to an image sensor that reads characters and marks printed on paper or plastic sheets.
[0002]
[Prior art]
Conventionally, in an image sensor that reads this type of mark sheet or the like, a plate glass is interposed as a reading window to keep the distance between the CCD and the reading sheet surface constant, and the mark sheet surface is in contact with 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.
[0003]
However, in such an image sensor structure, since the mark sheet is repeatedly conveyed in contact with the plate glass surface while being directly pressed, the glass surface is gradually roughened due to friction with the mark sheet surface, thereby causing white turbidity and scratches. Occurred and affected reading accuracy.
[0004]
Further, since the plate glass is bonded to the main body of the image sensor, there is a problem that the replacement workability of the glass alone is poor.
Further, when the replacement is performed, the entire plate glass also functions as a conveyance guide for the mark sheet, so that there is a problem that it is difficult to align with the conveyance guides provided before and after the image sensor.
[0005]
The present invention has been made in view of these points, and prevents reading clouding and damage, prolongs the reading window, and provides excellent workability when replacing the reading window. To provide image sensor technology.
[0006]
[Means for Solving the Problems]
The present invention provides an image sensor device that reads characters, symbols, or figures printed or written on a reading medium through a window by an optical element so that the reading medium is not in contact with the window surface of the window. The structure is provided with a bank portion projecting vertically from the window surface at a position outside the portion .
[0007]
Since the distance of the reading medium from the window portion is kept constant depending on the height of the bank portion, the reading medium can be read without directly contacting the window portion. Damage can be prevented.
[0008]
Further, by forming the bank part in a tooth form outside the window, Ru can function bank portion as underwriting guide and delivery guide reading medium to the image sensor device.
[0009]
Further, at this time, if the leading end of the conveyance guide formed in the concave-convex shape corresponding to the comb-tooth shape when viewed from the planar direction is inserted into the comb-shaped space, the bank from the conveyance guide of the reading medium is banked. Smooth transfer to the section. Further, if the leading end of the conveyance guide is bent toward the non-projecting direction of the bank portion, it is possible to prevent the reading medium end from being caught in the bank portion from the conveyance guide during conveyance.
[0010]
In addition, a pressure roller for pressurizing and conveying the reading medium on the window is provided vertically above the window, and the pressure roller has roller guides having a diameter larger than that of the pressure roller at both ends in the axial direction. A part of the bank part was configured to be in sliding contact with the peripheral surface of the roller guide (abutting part). Thus, the position of the pressure roller on the window portion Ru is defined.
[0011]
Moreover, the window part and the bank part were integrally formed as a guide block with a permeable resin. Thus, it is possible to obtain an integral molding of removable guide block relative to the casing, Ru can improve the productivity and maintainability of the image sensor device.
[0012]
Also, well as it separates the window portion with respect to conventional guide block with a glass plate or the like, in this case, Ru can extend the selectivity of the material of the guide block.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0014]
[Example 1]
FIG. 1 is a cross-sectional view of an image sensor according to an embodiment of the present invention, and FIG. 2 is a plan view thereof.
[0015]
The image sensor 1 according to the present embodiment is a so-called contact image sensor, and is of a type in which a signal is read by being in close contact with a medium on which marks, characters, symbols, barcodes, or the like are printed.
[0016]
The image sensor 1 includes a guide block 2 and a casing 3. The guide block 2 is detachably fixed to the casing 3 with screws 5.
[0017]
The upper surface of the guide block 2 of the present embodiment has a step structure (height h) composed of the flat surface 9 and the bank portion 13. As shown in FIG. 2, the bank portion 13 is formed in a comb-like shape in the outward direction with the window portion 14 at the center. Further, the end surface 19 of the bank portion 13 is processed into a slope having a certain inclination with respect to the vertical direction.
[0018]
Further, both end portions 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 the pressure roller 22 described later. Here, the height of the abutting portion 21 is the same as the height h of the other bank portion 13, but by adjusting the height of the abutting portion 21 during the processing of the guide block 2 or after the past, The degree of pressurization of the pressure roller 22 can be changed.
[0019]
The pressure roller 22 is formed of elastic synthetic rubber, synthetic resin, or the like, and the roller guide 23 is formed of hard synthetic resin or metal.
In the present embodiment, in the guide block 2 described above, the flat surface 9 and the bank portion 13 are integrally formed of a hard transparent resin such as polycarbonate.
[0020]
On the other hand, the casing 3 is made of metal or synthetic resin, and is obtained through extrusion molding of an aluminum alloy or the like, or a resin molding process.
Inside the casing 3, a lens unit 7 is disposed immediately below the window portion 14, and a light source unit 6 is attached to the outside of the lens unit 7. The light source unit 6 is composed of a light emitting diode array or the like, and irradiates the window portion 14 from obliquely below the window portion 14.
[0021]
A CCD 8 attached to the printed wiring board 10 is attached further below the lens unit 7 so that the mark state of the mark sheet 12 passing immediately above the window portion 14 is read by the difference in reflected light of the light source unit 6. It has become.
[0022]
An external connection connector 11 is provided below the side of the casing 3 to perform signal output from the CCD 8 to the outside, supply of driving power to the light source unit 6 and the printed wiring board 10 from the outside, and the like. Yes.
[0023]
A pressure roller 22 is disposed above the window portion 14. A roller guide 23 having a diameter larger than that of the pressure roller 22 is provided at the axial end of the pressure roller 22. The pressure roller 22 is rotated while the circumferential 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).
[0024]
3 and 4 show a state in which the conveyance guide 15 is arranged with respect to the image sensor 1 of the present embodiment.
As shown in FIG. 4, the conveyance guide 15 is obtained by processing one end of a plate material made of a stainless alloy into a planar concavo-convex shape, and this protrusion 16 enters the flat surface 9 of the guide block 2, and the guide 17 enters the guide 17. Position alignment with the image sensor 1 is made so that the bank part 13 of the block 2 is inserted.
[0025]
Further, the tip of the conveyance guide 15 (the portion of the projection 17) is slightly bent downward, that is, toward the non-projection direction of the bank 13, and the mark sheet 12 conveyed on the conveyance guide surface is It is configured to be smoothly (without being caught) transferred from the end surface 19 of the bank portion 13 to the upper surface of the bank portion 13.
[0026]
That is, the mark sheet 12 sent from the left to the right in FIG. 1 on the conveyance guide 15 passes over the bank portion 13 of the guide block 2 and passes over the window portion 14 while being pressed by the pressure roller 22. Move at a constant speed. At this time, the mark sheet 12 is moved in a non-contact state with respect to the window surface of the window portion 14 due to the height h of the bank portion 13.
[0027]
During this movement, a mark printed or written on one surface (the lower surface in FIG. 1) of the mark sheet 12 is irradiated from the light source unit 6 through the window portion 14. The reflected light of the irradiated light is read by the CCD 8 from the window portion 14 through the lens unit 7.
[0028]
As described above, according to the present embodiment, the bank sheet 13 of the guide block 2 allows the mark sheet 12 to pass through in a non-contact state with the window surface of the window section 14, so that the window surface of the window section 14 is in contact with the mark sheet 12. Can prevent damage or cloudiness.
[0029]
In addition, since the guide block 2 having the window portion 14 is attached to the casing 3 by the screw 5, it is possible to greatly improve the maintainability such as component replacement.
[0030]
In addition, in the conventional structure in which the window part and the guide are separated, there is a possibility that foreign matters such as dust may enter the gap between the window part and the guide. In the present embodiment, this is integrated. Because of the structure, there is no fear of this.
[0031]
[Example 2]
FIG. 5 is a cross-sectional view showing another embodiment of the present invention.
In the second embodiment, the configuration of the guide block 51 is different from the guide block 2 of the first embodiment. That is, in the present Example 2, the transparent plate glass 52 is attached to the part of the window part 14 of Example 1, and this plate glass 52 substantially comprises the window part. And the upper surface of this plate glass 52 is arrange | positioned so that it may become a position lower than the bank part 13 of the guide block 51. FIG.
[0032]
Thus, also in the present Example 2, 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 does not come into direct contact with the plate glass 52. The surface of 52 can be prevented from becoming clouded or damaged by friction.
[0033]
Furthermore, in the second embodiment, since the glass plate 52 constituting the window portion is formed separately from the guide block 2, the guide block 2 may be formed of an opaque synthetic resin, and the material selectivity is increased. .
[0034]
[Example 3]
FIG. 6 is a cross-sectional view showing another embodiment of the present invention.
The third embodiment is characterized by a mounting structure between the guide block 63 and the casing 64. In the first embodiment and the second embodiment, the guide block 2 is fixed to the casing 3 with the screw 5, but in the third embodiment, the guide block 2 has a fitting structure.
[0035]
The structure of the upper surface of the guide block 63 is the same as that of the first embodiment or the second embodiment, but a skirt 65 is extended from the outside on both sides of the guide block 63 to the lower side. A fitting claw 62 is formed to protrude.
[0036]
The fitting claws 62 are provided so as to be fitted with 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, it is only necessary to push the guide block 63 into the casing 64 from above.
[0037]
Further, when removing the guide block 63 from the casing 64, the guide block 63 is disengaged from the fitting claw 62 and the fitting groove 61 by releasing both the skirts 65 of the guide block 63 away from each other. Can be raised upward.
[0038]
Further, as a method of removing the guide block 63 from the casing 64, the fitting claw 62 may be removed by sliding the guide block 63 along the fitting groove 61 rearward or forward of the paper surface of FIG.
[0039]
[Example 4]
FIG. 7 is also characterized by the mounting structure between the guide block 73 and the casing 74. In the fourth embodiment, a skirt 75 is extended from the outer side to the lower side of the guide block 73, and a protrusion 72 is provided at the lower inner end of the skirt 75.
[0040]
The protrusions 72 are provided so as to be fitted with 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 protrusion 72 is inserted into the fitting groove 71 from the end in the longitudinal direction of the casing 74 and attached.
[0041]
Further, when the guide block 73 is removed from the casing 74, the protrusion 72 can be removed by sliding the guide block 73 along the fitting groove 71 to the rear or front of the paper surface of FIG.
[0042]
【The invention's effect】
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, and therefore, cloudiness due to wear caused by contact with the mark sheet is caused. Can prevent damage.
[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 illustrating a positional relationship between the image sensor and the conveyance guide. 4 is a plan view showing the positional relationship between the image sensor and the conveyance guide of the embodiment. FIG. 5 is a front sectional view of the image sensor of the second embodiment. FIG. 6 is a front sectional view of the image sensor of the third embodiment. FIG. 8 is a front sectional view of an image sensor according to a fourth embodiment. FIG. 8 is a side view showing the positional relationship between the image sensor and the pressure roller according to the embodiment of the present invention.
1 Image sensor 2 Guide block 3 Casing 5 Screw 6 Light source unit 7 Lens unit 8 CCD
9 Flat surface 10 Printed circuit board 11 Connector 12 Mark sheet 13 Bank portion 14 Window portion 15 Transport guide 16 Protrusion portion 17 Recess portion 19 End surface 21 Abutting portion 22 Pressure roller 23 Roller guide 51 Guide block 52 Sheet glass 61 Fitting groove 62 Mating claw 63 Guide block 64 Casing 65 Skirt 73 Guide block 74 Casing 75 Skirt

Claims (1)

An image sensor device that reads characters, symbols or figures printed or written on a reading medium through a window by an optical element,
A bank block projecting vertically from the window surface and a guide block formed integrally with the window portion at an outer position of the window portion so that the reading medium is not in contact with the window surface of the window portion. When,
A pressure roller disposed above the window,
The pressure roller is provided with roller guides having a diameter larger than that of the pressure roller at both ends in the axial direction, and the circumferential surface of the roller guide is applied while being in contact with the abutting portion as a part of the bank portion. An image sensor device that pressurizes and conveys a medium on a window by rotating a pressure roller .

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