JP3443258B2 - Image reading device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading apparatus using a contact image sensor for reading an image when a document to be conveyed is brought into close contact with a scanner roller.

[0002]

2. Description of the Related Art Some image reading apparatuses are provided with a contact image sensor which is composed of a light source and a photoelectric conversion element and which reads an image of a document being conveyed. In this image reading apparatus, a document is conveyed to the contact image sensor, and the document is brought into contact with the contact image sensor by the scanner roller. At this time, the contact image sensor reads the image on the document.

One of such image reading devices is disclosed in Japanese Patent Laid-Open No.
No. 2526261. This JP-A-4
In the image reading device described in Japanese Patent Publication No. 252661, a scanner roller is provided so that the position does not move, and a leaf spring that presses the contact image sensor is provided on the scanner roller. The leaf spring has one end abutting against the contact image sensor and the other end screwed to the bottom chassis so as to press the contact image sensor against the scanner roller. On its bottom chassis,
The contact image sensor is attached so as to come into contact with and separate from the scanner roller. In this image reading device, the contact image sensor is pressed against the scanner roller by the leaf spring, and the conveyed document is pressed against the contact image sensor by the scanner roller.

[0004]

In the above-mentioned image reading apparatus, the screw tightening work for screwing the leaf spring is performed at the time of service such as repair or inspection or at the time of assembly. At this time,
Overtightening the screws can damage them and render the component unusable.

Further, the workability is poor because an operator must hold the leaf spring at a predetermined position when attaching the leaf spring to the bottom chassis.

Further, since the driver must reach the screw during the screw tightening work, it is necessary to prevent the parts from being arranged around the screw. As a result, there are design restrictions on the arrangement of components, and miniaturization is difficult.

[0007]

The invention according to claim 1 is
A holding portion is arranged at a position facing the peripheral surface of the rotatable scanner roller, a fixing portion which is a part of a leaf spring is attached to the holding portion, and the holding portion is arranged between the scanner roller and the holding portion. A flexible portion formed by bending from the fixed portion is brought into contact with the contact image sensor, the contact image sensor is pressed against the scanner roller by the leaf spring, and a document is conveyed between the contact image sensor and the scanner roller. Then, in an image reading apparatus for reading the image on the original with the contact image sensor, a slide insertion for allowing the leaf spring to slide into the holding portion and positioning the leaf spring in a direction perpendicular to the holding portion. Part, the holding part and the leaf spring slidably inserted into the holding part are fitted to each other, and And a fitting portion for positioning the spring. Therefore, the leaf spring is slid into the holding portion, the position of the leaf spring in the direction perpendicular to the holding portion is determined by the slide insertion portion, and the holding portion and the leaf spring slid into the holding portion are fitted. Since the position of the leaf spring in the horizontal direction with respect to the holding portion is determined by the fitting portion, the leaf spring is attached to the holding portion by the slide insertion portion and the fitting portion, and the leaf spring is arranged at the regular position. .

According to a second aspect of the present invention, in the image reading apparatus according to the first aspect, when the contact image sensor moves to the holding portion side, the contact image sensor approaches the holding portion within a predetermined distance or less. The contact image sensor includes a restriction unit that restricts movement of the contact image sensor toward the holding unit.
However, the predetermined distance is set according to the leaf spring so that the leaf spring does not deform beyond the elastic limit even when the contact image sensor moves to the holding portion side and the leaf spring deforms. Therefore, when the contact image sensor is pressed against the holding portion side, the distance between the contact image sensor and the holding portion becomes a predetermined distance before the leaf spring is deformed beyond the elastic limit, so that the contact image sensor is held by the holding portion side. When the contact image sensor does not come closer to the holding portion than a predetermined distance, the leaf spring does not deform beyond the elastic limit, and the leaf spring may be permanently deformed. Disappear.

According to a third aspect of the present invention, the holding portion in the image reading apparatus according to the first or second aspect contacts one end of the contact image sensor downstream of the contact image sensor in the document conveying direction. A pressing portion is provided, and a leaf spring extends from the fixing portion to the upstream side of the contact image sensor in the conveying direction of the document and abuts on the other end of the contact image sensor. It is provided with a pressing portion that presses against. Therefore, by pressing the contact image sensor against the pressing portion by the pressing portion, the positional relationship between the scanner roller and the contact image sensor is maintained.

According to a fourth aspect of the present invention, the leaf spring in the image reading apparatus according to the first, second or third aspect has a hook portion extending from the fixed portion to the contact image sensor side. A hook protruding toward the contact image sensor side on the scanner roller side with respect to the holding portion side end of the contact image sensor is provided, and the contact image sensor is guided in a direction in which the contact image sensor approaches and separates from the scanner roller. Provide a guide part to Therefore, the contact image sensor is guided by the guide portion, and the contact image sensor moves in the direction of approaching and separating from the scanner roller. When the contact image sensor is guided to the scanner roller side by being guided by the guide portion, the hook comes into contact with the contact image sensor, and the hook portion regulates the range in which the contact image sensor moves to the scanner roller side. The contact image sensor is kept in a stable position even when the scanner roller is not attached at the time of assembly.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An image reading apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a front view showing the image reading apparatus of the present embodiment. A frame (not shown) of the image reading apparatus is provided with a conveyance path 2 for conveying the document 1. The scanner roller 3 and the CIS (contact image) are connected to the transport path 2 via the transport path 2.
sensor) unit 4 is arranged so as to face it. Below the CIS unit 4, a bottom chassis 5 serving as a holding portion is provided. In this bottom chassis 5,
A leaf spring 6 is attached which contacts the lower end of the CIS unit 4 and presses the upper end of the CIS unit 4 against the scanner roller 3.

The scanner roller 3 is rotatably provided around a roller shaft 7 rotatably attached to the frame. The roller shaft 7 has a bearing 8
Is attached. A bearing groove 9 is formed on the outer peripheral surface of the bearing 8 as shown in FIG.

The CIS unit 4 is provided with a contact image sensor (CIS) 10. This CIS1
Brackets 11 are screwed to both ends of 0.
The bottom portion of the bracket 11 is formed so as to project to the upstream side (the right side in FIG. 1) of the original 1 in the conveying direction with respect to the CIS 10. A slide portion 12 is formed on the bottom of the bracket 11 at a position downstream of the CIS 10 in the conveying direction of the document 1 and is perpendicular to the bottom. At the bottom of the bracket 11, the original document 1 is
The protrusion 13 that is horizontal to the bottom of the downstream side of the conveyance direction of the
Are formed. On both sides of the bracket 11,
A U-shaped portion 14 is formed. The U-shaped portion 14 is formed so as to engage with the bearing groove 9.

As shown in FIG. 3, the bottom chassis 5 is provided with two claw portions 15 which are slide insertion portions on a straight line orthogonal to the conveying direction of the original 1. These claws 1
A first convex portion 16 is formed between the five. Manuscript 1
A second convex portion 17 is formed on a straight line which is parallel to the transport direction of and passes through the first convex portion 16. The first and second convex portions 16 and 17 have a substantially hemispherical shape. A vertical wall 18, which is a vertical pressing portion that contacts the slide portion 12, is formed on the downstream side of the first and second convex portions 16 and 17 in the conveyance direction of the document 1. The vertical wall 18
The scanner roller 3 is formed by the slide roller 12 and the slide portion 12.
On the other hand, the CIS 10 moves in the direction in which
A guide portion 19 that guides 10 is provided. Notches 20 are formed at the left and right ends of the vertical wall 18 to allow the protrusion 13 to escape.

A flat plate portion 21 parallel to the upper surface of the bottom chassis 5 is formed on the claw portion 15. The claw portion 15
Is formed such that the distance between the flat plate portion 21 and the bottom chassis 5 is substantially equal to the thickness of the leaf spring 6.

The leaf spring 6 is composed of a fixing portion 22 that comes into contact with the bottom chassis 5 and a bending portion 23 that is bent from the fixing portion 22 and comes into contact with the bottom portion of the bracket 11. The fixing portion 22 has a long hole 24 that fits with the first convex portion 16 and a round hole 25 that fits with the second convex portion 17.
And are formed. The first and second convex portions 16 and 1
A fitting portion is formed by the 7, the long hole 24, and the round hole 25. The long hole 24 is formed long in the direction in which the original 1 is conveyed. The CI is provided at both ends in the width direction of the fixing portion 22.
A pressing portion 26 extending to the S10 side is formed. The pressing portion 26 is formed so as to abut on the end of the bottom of the bracket 11 on the upstream side in the transport direction of the document 1 and press the CIS 10 against the vertical wall 18. A hook portion 27 is formed on one of the pressing portions 26 above the bottom portion of the bracket 11. A hook 28 protruding toward the CIS 10 side is formed on the hook portion 27. A knob portion 29 is formed on the upper end of the other pressing portion 26.

At the end of the flexible portion 23 on the CIS 10 side, the end of the flexible portion 23 is the bottom chassis 5
A bent portion 30 that is an L-shaped bent portion that is a restriction portion is formed on the side. When the CIS 10 is pushed down and the leaf spring 6 is deformed, the bent portion 30 is bent.
The bent portion 30 is formed so as to come into contact with the bottom chassis 5 before being deformed beyond the elastic limit.

The CIS 10 includes a light source (not shown) for irradiating the original 1 with light and a photoelectric conversion element (not shown) for photoelectrically converting the reflected light from the original 1 and outputting image data. It is arranged.

In such a structure, the CIS 10 is pressed against the scanner roller 3 by the leaf spring 6, and the scanner roller 3 and the CIS 10 are brought into close contact with each other. When a start key (not shown) is pressed, the document 1 is conveyed to the position where the scanner roller 3 and the CIS 10 are in close contact with each other,
The original 1 comes into close contact with the scan line of the CIS 10, and the image on the original 1 is read by the CIS 10.
At this time, the pressing portion 26 of the leaf spring 6 presses the bracket 11 against the vertical wall 18 of the bottom chassis 5, and the scanner roller 3 and the CI are aligned in a state where the position where the CIS 10 is in close contact with the scanner roller 3 and the scan line of the CIS 10 match.
The positional relationship with S10 is maintained. Therefore, the position of the CIS unit 4 is prevented from being shifted to the upstream side or the downstream side in the transport direction of the document 1 due to the friction between the scanner roller 3 and the CIS 10. can get.

In addition, when the leaf spring 6 is attached at the time of service such as repair or inspection or at the time of assembly, an operator aligns the first convex portion 16 and the long hole 24, and the leaf plate 6 is provided along the bottom chassis 5. Slide the spring 6 to the vertical wall 18 side,
5, a part of the fixing part 22 is inserted between the flat plate part 21 of 5 and the bottom chassis 5 to fit the first convex part 16 and the long hole 24,
The second convex portion 17 and the round hole 25 are fitted together. As a result, the fixed portion 22 is held in contact with the bottom chassis 5, and the leaf spring 6 is attached to the bottom chassis 5. Therefore, it is not necessary to screw the leaf spring 6 to the bottom chassis 5 or the CIS unit 4. Further, the vertical position of the leaf spring 6 is determined by the flat plate portion 21 of the claw portion 15, and the first and second convex portions 16 and 17 are fitted into the long hole 24 and the round hole 25, whereby the leaf spring 6 is fitted. The horizontal position of 6 is determined, and the leaf spring 6 is arranged at the regular position. Therefore, since the leaf spring 6 can be easily positioned, workability at the time of mounting is improved.

Furthermore, when cleaning the CIS 10,
10 is pushed down, the scanner roller 3 and the CIS 10 are separated, and the dirt on the upper surface of the CIS 10 is wiped off. At this time, the CIS unit 4 is pushed down and the leaf spring 6
Even if the leaf spring 6 is deformed, the bent portion 30 of the leaf spring 6 contacts the bottom chassis 5 before the leaf spring 6 is deformed beyond the elastic limit, and the CIS unit 4 is restricted from moving to the bottom chassis 5 side. Therefore, the CIS unit 4 does not approach the bottom chassis 5 by a predetermined distance or more, the leaf spring 6 does not deform beyond the elastic limit, and the leaf spring 6 does not permanently deform. Therefore, the leaf spring 6 is CIS
The force of pressing 10 onto the scanner roller 3 is maintained, and the conveyed document 1 is prevented from being brought into close contact with the CIS 10 by the scanner roller 3 and degrading the focus of the read image. Further, when a plurality of leaf springs 6 are used, the force for pressing the CIS unit 4 against the scanner roller 3 does not vary among the leaf springs 6, and the skew of the document 1 does not occur.

When the scanner roller 3 is removed at the time of servicing or assembling, the leaf spring 6 causes the CIS to move.
The unit 4 is pushed upward. At this time, the slide portion 12 slides along the vertical wall 18, and the CIS unit 4 moves upward in a substantially parallel manner. Then, when the CIS unit 4 moves upward, the bottom of the bracket 11 abuts the hook 28, and the range in which the CIS unit 4 moves upward is restricted by the hook portion 27. Therefore, the leaf spring 6 causes the CIS 10 to jump upward. CIS1 even when the scanner roller 3 is not attached
0 is kept in a stable position. Therefore, the assembling work and the disassembling work become easy.

Although the case where the claw portion 15 is formed on the bottom chassis 5 has been described in the embodiment of the present invention, the slide insertion portion is not limited to the one including the claw portion 15, and, for example, A claw portion may be formed on the leaf spring 6 and a hole into which the claw portion of the leaf spring 6 is inserted may be formed on the bottom chassis 5.

Further, in the embodiment of the present invention, two convex portions 16 and 17 are formed on the bottom chassis 5, and the long hole 24 and the round hole 25 which are fitted into the convex portions 16 and 17 are fixed portions. Although the case where it is formed in 22 has been described, the fitting portion is not limited to the one including the two convex portions 16 and 17, the long hole 24, and the round hole 25. For example, the convex portion is fixed to the fixing portion 2.
2 may be formed in the bottom chassis 5 so as to be fitted into the fixing portion 22.

Further, in the embodiment of the present invention, the bent portion 30 formed on the leaf spring 6 is described as the auxiliary portion, but the auxiliary portion is not limited to the bent portion 30, and for example, the CIS unit. The columnar portion protruding to the 4 side is the bottom chassis 5
Alternatively, the columnar portion may be used as an auxiliary portion. At this time, the columnar portion is formed so as to contact the CIS unit 4 before the deformation amount of the leaf spring 6 exceeds the elastic limit of the leaf spring 6 when the CIS unit 4 is pushed down and the leaf spring 6 is deformed. ing.

[0026]

According to the first aspect of the present invention, the slide insertion portion that allows the leaf spring to slide into the holding portion and positions the leaf spring in the direction perpendicular to the holding portion, and the holding portion. The holding portion is fitted with the slidingly inserted leaf spring, and the holding portion and the fitting portion for positioning the leaf spring in the horizontal direction are provided, so that the leaf spring can be slid into the holding portion. The position of the leaf spring in the direction perpendicular to the holding portion can be determined by the slide insertion portion, the holding portion and the leaf spring slid and inserted in this holding portion can be fitted, and the position in the direction horizontal to the holding portion can be achieved. The position of the leaf spring can be determined by the fitting part,
As a result, the leaf spring can be attached to the holding portion by the slide insertion portion and the fitting portion, it is not necessary to screw the leaf spring, and the leaf spring can be arranged at the regular position. Workability can be improved.

According to the second aspect of the invention, when the contact image sensor moves to the holding portion side, the contact image sensor moves to the holding portion side before the contact image sensor approaches the holding portion by a predetermined distance or less. A predetermined distance is set according to the leaf spring so that the leaf spring does not deform beyond the elastic limit even when the contact image sensor moves to the holding portion side and the leaf spring deforms. Therefore, when the contact image sensor is pressed against the holding part side, the distance between the contact image sensor and the holding part becomes a predetermined distance before the leaf spring deforms beyond the elastic limit, and the contact image sensor is held by the holding part side. The movement is regulated by the regulation unit. This prevents the contact image sensor from approaching the holding portion by a predetermined distance or less, prevents the leaf spring from deforming beyond the elastic limit, and prevents the leaf spring from permanently deforming. Therefore, the force of the leaf spring pressing the contact image sensor against the scanner roller can be maintained, the conveyed document can be contacted with the contact image sensor, and the focus of the read image can be prevented from deteriorating. Further, when a plurality of leaf springs are used, the force for pressing the contact image sensor against the scanner roller does not vary from one leaf spring to another and skew of the document does not occur.

According to the third aspect of the invention, the holding portion is
A contact portion is provided downstream of the contact image sensor in the conveyance direction of the document, and has a pressing portion that comes into contact with one end of the contact image sensor, and a leaf spring extends from the fixed portion upstream of the contact image sensor in the conveyance direction of the document. The contact portion is provided with a pressing portion that comes into contact with the other end portion of the contact image sensor and presses the contact image sensor against the pressing portion. Can be maintained, and the position of the contact image sensor does not shift to the upstream side or the downstream side in the document conveyance direction due to the friction between the scanner roller and the contact image sensor. As a result, the read image is not distorted, and a good read image can be obtained.

According to the invention of claim 4, the leaf spring is
It has a hook portion extending from the fixed portion to the contact image sensor side, and the hook portion has a hook protruding toward the contact image sensor side on the scanner roller side from the end portion on the holding portion side of the contact image sensor, Since the guide unit is provided to guide the contact image sensor in the direction in which the contact image sensor approaches and separates from the scanner roller, the contact image sensor is guided by the guide unit and moves the contact image sensor in the direction toward and away from the scanner roller. Can be made. Then, when the contact image sensor is guided to the scanner roller side by being guided by the guide portion, a hook is brought into contact with the contact image sensor, and the range in which the contact image sensor moves to the scanner roller side can be restricted by the hook portion. Thus, the contact image sensor can be kept in a stable position even when the scanner roller is not attached at the time of service or assembly. Therefore, the assembling work and the disassembling work can be easily performed.

[Brief description of drawings]

FIG. 1 is a front view showing an image reading apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view showing the image reading apparatus with a scanner roller removed.

FIG. 3 is a plan view showing a leaf spring and a part of a holding portion.

FIG. 4 is a front view showing a leaf spring.

[Explanation of symbols]

1 manuscript 3 Scanner roller 5 holding part 6 leaf spring 10 Contact image sensor 15 Slide insertion part 16, 17, 24, 25 Fitting part 18 Presser section 19 Guide section 22 Fixed part 23 Deflection part 26 Pressing part 27 Hook part 28 hooks 30 Regulation Department

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H04N 1/00 H04N 1/028

Claims (4)

(57) [Claims] 1. A holding portion is arranged at a position facing a peripheral surface of a rotatable scanner roller, and a fixing portion which is a part of a leaf spring is attached to the holding portion to connect the scanner roller and the holding portion. A contact portion of the contact image sensor disposed between the fixed portions is bent and bent, and the contact image sensor is pressed against the scanner roller by the leaf spring. In an image reading device that conveys an original document between and reads the image on the original document with the contact image sensor, the leaf spring is allowed to slide into the holding unit and the leaf spring in a direction perpendicular to the holding unit. The slide insertion part for positioning, the holding part, and the leaf spring slidly inserted into the holding part are fitted to each other, and the one that is horizontal to the holding part. Image reading apparatus characterized by comprising a fitting portion for positioning of the leaf spring in. 2. A regulation for restricting the contact image sensor from moving to the holding part side before the contact image sensor approaches the holding part when the contact image sensor moves to the holding part side. The image reading apparatus according to claim 1, further comprising a section. 3. The holding portion has a holding portion which comes into contact with one end of the contact image sensor downstream of the contact image sensor in the conveying direction of the document, and the leaf spring has a position more than that of the contact image sensor. 3. The pressing unit, which extends upstream from the fixing unit in the conveying direction of the document, abuts against the other end of the contact image sensor and presses the contact image sensor against the pressing unit. Image reading device. 4. The leaf spring has a hook portion extending from the fixed portion attached to the holding portion to the contact image sensor side, and the hook portion is closer to the scanner than the end portion of the contact image sensor on the holding portion side. 2. A hook that projects toward the contact image sensor on the roller side is provided, and a guide portion that guides the contact image sensor in a direction in which the contact image sensor approaches and separates from the scanner roller is provided. 2. The image reading device described in 2 or 3.