JPH1075332A - Image reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the image reader having a leaf spring to press a close contact image sensor onto a scanner roller so as to mount the leaf spring to a support without using any screw. SOLUTION: In the image reader, a leaf spring 6 is fitted to a support 5 and a close contact image sensor 10 placed between a scanner roller 3 and the support 5 is pushed onto the scanner roller 3 by the leaf spring 6. In this case, part of the leaf spring 6 in contact with the support 5 is used for a stator part 22 and part of the leaf spring 6 in press contact with the close contact image sensor is used for a deflection part 23. The leaf spring 6 is skided along the support 5 to form a slide insert part to which the stator part 22 is inserted, and while the stator part 22 is inserted to the slide insert part, the slide insert part forms fitting parts 16, 17, 24, 25.

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 by bringing a conveyed document into close contact with a scanner roller.

[0002]

2. Description of the Related Art Some image reading apparatuses include a contact image sensor that includes a light source and a photoelectric conversion element and reads an image of a conveyed document. In this image reading apparatus, a document is transported to the contact image sensor, and the document is brought into close contact with the contact image sensor by a scanner roller. At this time, the contact image sensor reads an image on the document.

One of such image reading apparatuses is disclosed in Japanese Unexamined Patent Publication No.
No. 252661. This Japanese Patent Laid-Open No. 4
In the image reading apparatus described in JP-A-252661, a scanner roller is provided so as not to move, and a leaf spring for pressing a contact image sensor against the scanner roller is provided. One end of the leaf spring is in contact with the contact image sensor, and the other end is screwed to the bottom chassis so that the contact image sensor is pressed against the scanner roller. In the 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 apparatus, 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-described image reading apparatus, a screwing operation for screwing a leaf spring is performed at the time of service such as repair or inspection or at the time of assembly. At this time,
If the screw is tightened too much, the screw may break and the part itself may not be usable.

Further, when the leaf spring is attached to the bottom chassis, the operator must hold the leaf spring at a predetermined position, so that the workability is poor.

Furthermore, since the driver must reach the screw during the screw tightening operation, it is necessary to prevent components from being arranged around the screw. As a result, there is a design restriction on the arrangement of components, and it is difficult to reduce the size.

[0007]

According to the first aspect of the present invention,
A holding portion is arranged at a position facing the peripheral surface of the rotatable scanner roller, a fixed 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 bent portion formed 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. In the image reading apparatus for reading an image on the original by the close 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 portion and the leaf spring slidably inserted into the holding portion are fitted to each other, and the And a fitting portion for positioning the spring. Therefore, the leaf spring is slid into the holding part, the position of the leaf spring in the direction perpendicular to the holding part is determined by the sliding insertion part, and the holding part and the leaf spring slid into the holding part 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 toward the holding portion, the contact image sensor is moved to the holding portion before the image sensor approaches the holding portion. The image forming apparatus further includes a regulating unit that regulates movement of the contact image sensor toward the holding unit.
However, the predetermined distance is set in accordance with the leaf spring so that the leaf spring does not exceed the elastic limit and is not deformed even when the contact image sensor moves to the holding unit side and the leaf spring is deformed. Therefore, when the contact image sensor is pressed against the holding unit, the distance between the contact image sensor and the holding unit becomes a predetermined distance before the leaf spring is deformed beyond the elastic limit. The movement of the leaf spring is restricted by the restricting section, the contact image sensor does not approach the holding section below a predetermined distance, the leaf spring does not deform beyond the elastic limit, and the leaf spring is permanently deformed. Disappears.

According to a third aspect of the present invention, in the image reading apparatus according to the first or second aspect, the holding portion abuts one end of the close contact image sensor downstream of the close contact image sensor in the document conveying direction. A holding portion, wherein a leaf spring extends from the fixed portion upstream of the contact image sensor in the direction of conveyance of the document and abuts on the other end of the contact image sensor, and presses the contact image sensor to the holding portion. And a pressing portion that presses the pressing portion. 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, in the image reading apparatus of the first, second or third aspect, the leaf spring 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 image sensor side closer to the scanner roller than an end on the holding portion side of the image sensor, and guiding the image sensor in a direction in which the image sensor approaches and separates from the scanner roller; A guide part is provided. Therefore, the contact image sensor is guided by the guide portion, and the contact image sensor moves in a direction approaching and separating from the scanner roller. When the contact image sensor is guided by the guide portion and moves to the scanner roller side, the hook comes into contact with the contact image sensor, and the range in which the contact image sensor moves to the scanner roller side is regulated by the hook portion. Even when the scanner roller is not attached at the time of assembly, the contact image sensor is maintained at a stable position.

[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 according to the present embodiment. A transport path 2 through which the document 1 is transported is provided in a frame (not shown) of the image reading apparatus. The transport path 2 has a scanner roller 3 and a CIS (contact image) via the transport path 2.
sensor) unit 4 is disposed so as to face the unit. Below the CIS unit 4, a bottom chassis 5 as a holding unit is provided. In this bottom chassis 5,
A leaf spring 6 which is in contact with the lower end of the CIS unit 4 and presses the upper end of the CIS unit 4 against the scanner roller 3 is attached.

The scanner roller 3 is rotatably provided around a roller shaft 7 rotatably mounted on the frame. The roller shaft 7 has a bearing 8
Is attached. As shown in FIG. 2, the bearing 8 has a bearing groove 9 formed on the outer peripheral surface of the bearing 8.

The CIS unit 4 includes a contact image sensor (CIS) 10. This CIS1
Brackets 11 are screwed to both ends of 0.
The bottom of the bracket 11 is formed so as to protrude further upstream (to the right in FIG. 1) in the transport direction of the document 1 than the CIS 10. On the bottom of the bracket 11, a slide portion 12 is formed, which is perpendicular to the bottom of the bracket 11 on the downstream side of the CIS 10 in the transport direction of the document 1. At the bottom of the bracket 11, the original 1
The bottom 13 and the horizontal projection 13 on the downstream side in the conveyance direction
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 formed with two claws 15 which are slide insertion portions on a straight line perpendicular to the direction in which the document 1 is conveyed. These nails 1
5, a first convex portion 16 is formed. Manuscript 1
A second convex portion 17 is formed on a straight line passing through the first convex portion 16 in parallel with the transport direction of the first convex portion. The first and second convex portions 16, 17 have a substantially hemispherical shape. A vertical wall 18 is formed on the downstream side of the first and second convex portions 16 and 17 in the transport direction of the document 1 as a vertical pressing portion that comes into contact with the slide portion 12. The vertical wall 18
The scanner roller 3 is formed by the
In the direction in which the CIS 10 approaches and separates.
A guide section 19 for guiding the apparatus 10 is provided. Notches 20 are formed at both left and right ends of the vertical wall 18 to allow the protrusion 13 to escape.

The claw portion 15 is formed with a flat plate portion 21 parallel to the upper surface of the bottom chassis 5. The claw 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 includes a fixed portion 22 that contacts the bottom chassis 5 and a bent portion 23 that is bent from the fixed portion 22 and contacts the bottom of the bracket 11. The fixing portion 22 has a long hole 24 fitted to the first convex portion 16 and a round hole 25 fitted to the second convex portion 17.
Are formed. The first and second convex portions 16, 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 transport direction of the document 1. At both ends in the width direction of the fixing portion 22, the CI
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. On one pressing portion 26, a hook portion 27 is formed above the bottom of the bracket 11. The hook portion 27 is formed with a hook 28 protruding toward the CIS 10. At the upper end of the other pressing portion 26, a knob portion 29 is formed.

At the end of the bent portion 23 on the side of the CIS 10, the end of the bent portion 23 is connected to the bottom chassis 5.
A bent portion 30 serving as a restricting portion is formed by being bent in an L-shape on the side. When the CIS 10 is pressed down and the leaf spring 6 is deformed, the bent portion 30
The bent portion 30 is formed so as to abut the bottom chassis 5 before is 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 reflected light from the original 1 and outputting image data. Are located.

In such a configuration, the CIS 10 is pressed against the scanner roller 3 by the leaf spring 6, and the scanner roller 3 and the CIS 10 come into close contact with each other. When a start key (not shown) is pressed, the original 1 is conveyed to a position where the scanner roller 3 and the CIS 10 are in close contact with each other, and
The document 1 comes into close contact with the scan line of the CIS 10, and an image on the document 1 is read by the CIS 10.
At this time, the bracket 11 is pressed against the vertical wall 18 of the bottom chassis 5 by the pressing portion 26 of the leaf spring 6, and the scanner roller 3 and the CI are scanned 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 coincide.
The positional relationship with S10 is maintained. Accordingly, the position of the CIS unit 4 does not shift 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, so that the read image is not distorted, and a good read image is obtained. can get.

When attaching the leaf spring 6 at the time of service such as repair or inspection, or at the time of assembling, the operator aligns the first convex portion 16 with the elongated hole 24 and moves the plate along the bottom chassis 5. Slide the spring 6 toward the vertical wall 18 side, and
5, a part of the fixed portion 22 is inserted between the flat plate portion 21 and the bottom chassis 5, the first convex portion 16 and the long hole 24 are fitted,
The second convex portion 17 and the round hole 25 are fitted. 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, there is no need 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, 17 are fitted to the long hole 24 and the round hole 25, so that the leaf spring 6 6 is determined, and the leaf spring 6 is arranged at a regular position. Therefore, since the leaf spring 6 can be easily positioned, workability at the time of mounting is improved.

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

When the scanner roller 3 is removed during service or assembling, the CIS is
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 and substantially in parallel. When the CIS unit 4 moves upward, the bottom of the bracket 11 abuts on the hook 28, and the range in which the CIS unit 4 moves upward is regulated by the hook 27, so that the CIS 10 jumps upward by the leaf spring 6. Will not occur, and the CIS 1
0 is kept in a stable position. Therefore, the assembling work and the disassembling work are facilitated.

In the embodiment of the present invention, the case where the claw portion 15 is formed on the bottom chassis 5 has been described. However, the slide insertion portion is not limited to the one formed with the claw portion 15. A claw portion may be formed in the leaf spring 6, and a hole into which the claw portion of the leaf spring 6 is inserted may be formed in 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 a long hole 24 and a round hole 25 fitted with the convex portions 16 and 17 are fixed portions. Although the description has been given of the case where the fitting portion 22 is formed, 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 portion 2
2 and a hole to be fitted with the fixing portion 22 may be formed in the bottom chassis 5.

Further, in the embodiment of the present invention, the bent portion 30 formed on the leaf spring 6 has been described as an auxiliary portion. However, the auxiliary portion is not limited to the bent portion 30, and may be, for example, a CIS unit. The columnar portion protruding to the side 4 is
And the columnar portion may be used as an auxiliary portion. At this time, the columnar portion is formed such that when the CIS unit 4 is pushed down and the leaf spring 6 is deformed, the deformation of the leaf spring 6 contacts the CIS unit 4 before the amount of deformation exceeds the elastic limit of the leaf spring 6. ing.

[0026]

According to the first aspect of the present invention, a slide insertion portion for allowing the leaf spring to slide into the holding portion and positioning the leaf spring in a direction perpendicular to the holding portion; Since the holding portion is fitted with a leaf spring slid and inserted, and the holding portion and a fitting portion for positioning the leaf spring in a horizontal direction are provided, the leaf spring can be slid and inserted 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, and the holding portion and the leaf spring slidably inserted into the holding portion can be fitted to each other. The position of the leaf spring can be determined by the fitting part,
Thereby, the leaf spring can be attached to the holding portion by the slide insertion portion and the fitting portion, and the leaf spring does not need to be screwed. Further, the leaf spring can be arranged at a regular position, and the Workability can be improved.

According to the second aspect of the present invention, when the close contact image sensor moves toward the holding portion, the close contact image sensor moves toward the holding portion before the close contact image sensor approaches the holding portion at a predetermined distance or less. The predetermined distance is set according to the leaf spring so that the leaf spring does not exceed the elastic limit and is not deformed even when the contact image sensor moves to the holding part side and the leaf spring is deformed. Therefore, when the contact image sensor is pressed against the holding portion, 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, and the contact image sensor is moved to the holding portion side. Is restricted by the restriction unit. This prevents the contact image sensor from approaching the holding portion below a predetermined distance, prevents the leaf spring from being deformed beyond its elastic limit, and prevents the leaf spring from being permanently deformed. Therefore, the force by which the leaf spring presses the contact image sensor against the scanner roller can be maintained, the conveyed document can be brought into contact 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 for each leaf spring, and the skew of the document does not occur.

According to the third aspect of the present invention, the holding portion is
There is a pressing portion that abuts one end of the contact image sensor downstream of the contact image sensor in the document transport direction, and a leaf spring extends from the fixed portion upstream of the contact image sensor in the document transport direction. The contact portion is provided with a pressing portion that contacts the other end of the contact image sensor and presses the contact image sensor against the pressing portion, so that the pressing portion can press the contact image sensor against the pressing portion, and the scanner roller and the contact image sensor can be pressed. Is 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. Accordingly, the read image is not distorted, and a good read image can be obtained.

According to the fourth aspect of the present invention, the leaf spring is
A hook portion extending from the fixed portion to the contact image sensor side, the hook portion includes a hook protruding toward the contact image sensor on the scanner roller side from the end of the holding portion side of the contact image sensor, A guide section is provided to guide the close contact image sensor in the direction in which the close contact image sensor approaches and separates from the scanner roller. Can be done. When the contact image sensor is guided by the guide portion and moves to the scanner roller side, the 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 regulated by the hook portion. Accordingly, the contact image sensor can be kept at 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 the drawings]

FIG. 1 is a front view illustrating 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 unit.

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Original 3 Scanner roller 5 Holding part 6 Leaf spring 10 Contact image sensor 15 Slide insertion part 16, 17, 24, 25 Fitting part 18 Holding part 19 Guide part 22 Fixed part 23 Flexure part 26 Pressing part 27 Hook part 28 Hook 30 Regulatory department

Claims (4)

[Claims] A holding portion is disposed 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. The bent portion formed by bending from the fixed portion is brought into contact with the contact image sensor disposed therebetween, and the contact image sensor is pressed against the scanner roller by the leaf spring, and the contact image sensor and the scanner roller are connected to each other. An image reading apparatus that conveys a document between the document and reads an image on the document with the contact image sensor, wherein the leaf spring in a direction perpendicular to the holding unit is allowed to slide the leaf spring into the holding unit. A slide insertion portion for positioning, the holding portion and the leaf spring slidably inserted into the holding portion are fitted to each other, and Image reading apparatus characterized by comprising a fitting portion for positioning of the leaf spring in. 2. A restriction for restricting the contact image sensor from moving toward the holding portion before the contact image sensor approaches the holding portion when the contact image sensor moves toward the holding portion when the contact image sensor moves toward the holding portion. The image reading device according to claim 1, further comprising a unit. 3. The holding unit has a pressing unit that comes into contact with one end of the contact image sensor at a position downstream of the contact image sensor in the document transport direction, and the leaf spring is more than the contact image sensor. 3. The image forming apparatus according to claim 1, further comprising a pressing portion that extends from the fixed portion on the upstream side in the document conveying direction, abuts on the other end of the contact image sensor, and presses the contact image sensor against the pressing portion. Image reading device. 4. The leaf spring has a hook portion extending from a 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 of the contact image sensor on the holding portion side. 2. The device according to claim 1, further comprising: a hook protruding toward the contact image sensor on a roller side; and a guide portion for guiding the contact image sensor in a direction in which the contact image sensor approaches and separates from the scanner roller. 4. The image reading device according to 2 or 3.