JPH11187224A - Image reader and reflecting mirror supporting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the vibration of a reflection mirror to prevent image shake by supporting ends at both sides in a longitudinal direction, at the side of a reflection surface of the reflection mirror by plural supporting parts. SOLUTION: A third mirror (reflecting mirror) 22 is supported by projecting parts 26 to 28 at three positions. This device is provided with a front opening part 24 and a rear opening part 25 which are opposite to each other at the front and the rear sides of a second mirror stand frame body 23, so that the reflection mirror 22 is inserted into the openings. In addition, the projecting part 26 the tip of which is butted against the reflection mirror 22 is provided at almost the center of mirror width to project from the second mirror stand frame body 23 to the front opening 24. Furthermore, the projecting parts 27, 28 with the same projection quantity and whose tips are butted against the reflecting mirror 22 are provided at almost both ends of the mirror width to project from the second mirror stand frame body 23 to the rear opening 25. The reflecting mirror 22 is pressurized from the back by left sprints 29, 30, and the reflection surface 22a is butted against the projecting parts 26 to 28 and positioned.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a document reading device and a reflection mirror support device for reading an image of a document placed and fixed on a contact glass by moving and scanning a scanning optical unit.

[0002]

2. Description of the Related Art Conventionally, as an image reading device for reading an image of a document, a scanning optical unit moves and scans,
2. Description of the Related Art A scanning-type image reading device that reads an image of a document placed and fixed on a contact glass has been proposed.

In such a scanning type image reading apparatus, a mirror for turning back the reflected light of the exposed document is generally provided in the scanning optical section.

FIGS. 6 and 7 show a conventional mirror supporting method.

The mirror 101 has its reflection surface 101a facing the mirror support 1 provided on the scanning optical unit frame 102.
Positions are located at 03, 104 and 105. Also,
The mirror 101 is pressed from its back by leaf springs 106 and 107 to provide mirror support portions 103, 104 and 105.
Is stably hit. The reason why the contact is made at three points is to prevent the mirror reflection surface 101a from being twisted due to the contact.

[0006]

The above-described scanning type image reading apparatus has a structure in which the reflected light is focused on a reading element through a lens while moving the scanning optical section.

[0007] In an apparatus having such a configuration, a problem of image blurring tends to occur. This image blur is often caused mainly by the vibration of the mirror. That is, the vibration of the motor driving the scanning optical unit and the vibration due to the sliding resistance with the rail when the scanning optical unit moves are transmitted to the mirror to vibrate the mirror, and the vibration also causes the optical path of the reflected light to vibrate. Image blurring occurs.

In particular, when the mirror is positioned by three-point support as described above, the vibration of the part supporting one point in the mirror longitudinal direction is more likely to cause image blur than the part supporting two points in the mirror longitudinal direction. It has a significant effect. That is, as shown in FIG. 7, the mirror 101 vibrates so as to be twisted in the directions of the arrows E and F about the near-side mirror support portion 103, causing image blurring.

[0009]

The main aspects of the present invention are as described below with reference to the claims.

According to a first aspect of the present invention, there is provided a platen glass on which a document can be placed, an illuminating means for illuminating the document placed on the platen glass, and at least one of a means for turning back reflected light from the illuminated document. And a lens for condensing reflected light from the document and forming an image on an image forming section, wherein the mirror has an elongated substantially rectangular shape, Is an image reading apparatus characterized in that a surface opposite to the reflection surface side is pressurized and both longitudinal end portions on the reflection surface side are supported by at least two support portions, respectively. .

A second invention according to the present application is a document reading apparatus in which at least one scanning optical unit moves and scans a placed document surface to read an image of a document, and the scanning optical unit includes: Has at least one reflection mirror that folds the reflected light from the illuminated document, the mirror has an elongated and substantially rectangular shape, and the mirror is pressed and reflected on a surface opposite to the reflection surface side. An image reading apparatus, wherein both end portions in the longitudinal direction on the surface side are supported by at least two support portions, respectively.

An eighth invention according to the present application is directed to a supporting device for a long and substantially rectangular reflecting mirror, which presses a surface of the reflecting mirror opposite to the reflecting surface side so that both ends of the reflecting surface side in the longitudinal direction are pressed. , Each of which is supported by at least two support portions.

[0013]

(Embodiment 1) Hereinafter, the present invention will be described in detail with reference to the drawings.

First, FIG. 5 shows a main part of an image reading apparatus applicable to the present invention.

Reference numeral 1 denotes an image reading device. Reference numeral 2 denotes a first mirror base as a scanning optical unit. Reference numeral 3 denotes a second mirror base as a scanning optical unit. 4 is a platen glass, 5 is a lens, 6 is a CCD sensor as an image reading element.

The first mirror base 2 comprises an exposure lamp 7, reflection shades 8, 9, a first mirror 10, a first mirror base frame 11, and the like. The first mirror base 2 is mounted on the guide rails 12 and 13 by its own weight, is fixed to the wires 19 and 20, and is movable in the directions of arrows A and B. A motor 14 drives the first mirror base.
The motor 14 is fixed to the frame 15 of the image reading device 1. The driving force of the motor 14 is transmitted to the first mirror base 2 via the driving shaft 16, pulleys 17, 18, and wires 19, 20.

The second mirror base 3 includes a second mirror 21 and a third mirror
It is composed of a mirror 22, a second mirror frame 23 and the like. The second mirror base 3 is guided by the guide rails 12, 1 under its own weight.
3 is on top. The second mirror base 3 has a drive motor 1
4 and is movable in the directions of arrows A and B. The driving force of the motor 14 is transmitted to the second mirror base 3 via the driving shaft 16, pulleys 17 and 18, and wires 19 and 20. The moving speed of the first mirror base 2 and the second mirror base 3 is set to be 2: 1.
The operation of the above-described image reading apparatus 1 is as follows.

In FIG. 3, an original is placed on a platen glass 4. Before the start of scanning, the first mirror table 2 is located at the left end of the document so that the document is illuminated from the left end of the document, and the second mirror table 3 is located to the left of the first mirror table 2 located at the left end of the document.

The exposure lamp 7 is energized, the motor 14 rotates clockwise, the drive shaft 16 and the pulley 17 rotate in the same direction, and the wire wound around and wound around the pulley 17 and pulled out from above. 19 and 20 go right. The first mirror base 2 fixed to the upper extending portions of the wires 19 and 20 is supported and guided by the guide rails 12 and 13. The reflection image of the document illuminated by the exposure lamp 7 through the platen glass 4 is reflected by the first mirror 10 and is reflected by the second mirror 2.
First, the light is reflected by the third mirror 22 and forms an image on the CCD sensor 6 by the lens 5.

The above-mentioned wires 19 and 20 which are pulled out from the upper sides of the pulleys 17 and 18 are wound around from the upper side, wound up, and pulled out from the lower side in the reflection direction (only the near side is shown). Is rotatably supported by the second mirror base 3. The ends of the wires 19 and 20 that extend from the fixed portion to the first mirror base 2 and are wound from the upper side to the lower side of the pulley 51 and pulled out in the opposite direction are fixed to the frame 15, 19 and 20, the second mirror base 3 along with the first mirror base 2 is guided by the guide rails 12 and 13 and moves rightward at half the speed of the first mirror base 2, whereby the optical path length is reduced. Adjusted.

Next, the structure of the mirror support which is a main part of the present invention will be described. The above-mentioned reflection mirrors 10, 21,
The present invention can be applied to any of the mirrors 22, but the third mirror 22 will be described as a representative.

FIGS. 1 and 2 show the details of the third mirror support.

On the front side and the back side of the second mirror base frame 23, a front side opening 24 and a back side opening 25 are provided so as to face each other, and the third mirror 22 is inserted therein. I have. A projection 26 is provided at the approximate center of the mirror width so as to project the tip against the reflection mirror 22 so as to project from the second mirror base frame 23 to the front opening 24. Further, projecting portions 27 and 28 are provided at substantially both ends of the mirror width so as to project the distal end to the reflecting mirror 22 having the same amount of projection so as to project from the second mirror frame 23 to the rear opening 25. . The reflection mirror 22 is provided on the leaf spring 2 from behind.
9 and 30, and the reflection surface 22a is
It is positioned by abutting on 7, 28.

Auxiliary projections 31 and 32 are provided at substantially both ends of the mirror width so as to project from the second mirror base frame 23 to the front opening 24. Third mirror 22
When the auxiliary projections 31 and 32 abut on the near side projection 26, the auxiliary projections 31 and 32 do not abut on the third mirror 22 and have a small amount x.
The height of the auxiliary projections 31 and 32 is set so that only a gap is left.

In the above-described state, the third mirror 22 is supported by the three projections 26, 27 and 28.

Further, in the present invention, the gap x
The adhesive material S is poured into and fixed. As the adhesive S,
Initially, it has a certain viscosity enough to fill the gap x,
A type that gradually cures with time and hardly shrinks with curing is preferable. For example, an epoxy-based adhesive is suitable. The adhesive S hardens over time while following the third mirror reflection surface 22a. Therefore, after curing, the adhesive S is integrated with the auxiliary projections 31 and 32 and follows the reflection surface 22a at three locations together with the front projection 26. That is, the front end of the third mirror reflection surface 22a is supported at three places without deforming the third mirror 22. In other words, the third mirror reflection surface 22a is supported by the same surface at five locations, namely, 26, 27, 28, 31, and 32, in abbreviated names, together with the back side.

(Embodiment 2) Next, Embodiment 2 will be described.

FIGS. 3 and 4 show details of the third mirror support of the second embodiment. The same components as those in the first embodiment or the components having the same functions are denoted by the same reference numerals and description thereof is omitted.

On the front side and the back side of the second mirror base frame 23, a front side opening 33 and a back side opening 34 are provided so as to face each other, and the third mirror 22 is inserted therein. I have. A projection 35 for abutting the mirror is provided at substantially the center of the mirror width so as to project from the second mirror frame 23 to the front opening 33. Furthermore, the second
Projections 36 and 37 for abutting mirrors having the same amount of projection are provided at substantially both ends of the mirror width so as to project from the mirror frame 23 to the rear opening 34. The third mirror 22 is pressed against the leaf springs 38, 39 from behind, and the reflecting surface 22a abuts on the protrusions 35, 36, 37 to be positioned.

Adjusting pieces 40 and 41 are provided at substantially both ends of the mirror width so as to protrude from the second mirror base frame 23 to the front opening 33. Even when the third mirror 22 abuts on the near side projection 35, the adjustment piece 40,
41 is a gap y by a predetermined amount without hitting the third mirror 22
The heights of the adjustment pieces 40 and 41 are set so that are empty. Adjusting screws 42 and 43 are screwed into the adjusting pieces 40 and 41. The adjustment screws 42 and 43 are adjustable in the directions of arrows C and D. Before the third mirror 22 is assembled, the adjustment screws 42 and 43 are set so as not to protrude beyond the protrusion 35.

From this state, the third mirror 22 is assembled into the third mirror base frame 23.

In the above-described state, the third mirror 22 is supported by the three projections 35, 36, and 37.

Thereafter, the adjusting screws 42 and 43 are screwed in the direction of arrow C, and the tip is adjusted so as to be in direct contact with the third mirror reflecting surface 22a. Therefore, after the adjustment, the adjusting screws 42 and 43 follow the reflecting surface 22a at three places together with the near-side protrusion 35. That is, the front end of the third mirror reflection surface 22a is supported at three places without deforming the third mirror 22. That is, the name is omitted and the code is 35, 3
The third mirror reflection surface 22a is supported by the same surface at five locations of 6, 37, 42, and 43.

In each of the above embodiments, the case where the support portions are provided at five positions has been described, but the number of the support portions is not limited to this.

In the above embodiment, the third mirror has been described as an example, but the present invention is not limited to this. It goes without saying that the first and second mirrors may be used, and mirrors (mirrors fixed in the apparatus or the like) used other than the scanning optical unit may be used.

In the first embodiment, the description has been made assuming that the number of bonding points is two. However, the present invention is not limited to this.

In the second embodiment, the adjustment is described as having two locations, but the present invention is not limited to this.

It is also possible to combine the two embodiments of the present invention. For example, in Embodiment 2, two adjustment support portions may be adhered after adjustment. In this case, the adjusting screws 42, 43 may be abutted against the reflecting surface 22a, or a gap may be provided between the tips of the adjusting screws 42, 43 and the reflecting surface 22a.

In the present invention, the image forming section is a CCD sensor. However, this image reading apparatus may be employed in, for example, an electrophotographic image forming apparatus, and the image forming section may directly form an image on an electrophotographic photosensitive member. The image formed by the CCD sensor is A / D converted and subjected to signal processing, converted into a laser corresponding to the time-series electronic signal of the target image, and a latent image is formed on the electrophotographic photosensitive member by a rotating polygon mirror and an fθ lens. You may do so.

In the present embodiment, the original is placed on the platen glass and the lower surface of the original is read by the scanning optical device. However, as shown in FIG. By using the supply device D, the document B on the tray 52 is moved on the platen glass 4 on the exposure lamp 7 to read the document image, and is transferred to the document reading device 1 capable of discharging the document image onto the discharge tray 53. The first mirror 10, the second mirror 21, and the third mirror 2, which are used as reflection mirrors
The present invention is applied to the second support.

As shown in FIG. 9, the image reading apparatus 1 shown in FIG. 5 is turned upside down and the original image is read by pressing the platen glass 4 onto the original B on the original placing table 54. However, the present invention is applied. The present invention is also applied to a document reading unit of a character recognition device (OCR).

[0042]

As described above, according to the present invention,
By supporting both end portions in the longitudinal direction on the reflection surface side of the reflection mirror with at least two support portions, vibration of the reflection mirror can be effectively prevented. That is, an abnormal image called image blur can be effectively prevented.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating Embodiment 1 of the present invention.

FIG. 2 is a view on arrow P of FIG. 1;

FIG. 3 is a perspective view illustrating Embodiment 3 of the present invention.

FIG. 4 is a view on arrow P of FIG. 3;

FIG. 5 is a schematic perspective view of a document reading apparatus to which the present invention is applied.

FIG. 6 is a perspective view of a conventional example.

FIG. 7 is a view as seen from the arrow P in FIG. 6;

FIG. 8 is a longitudinal sectional view of another image reading apparatus to which the present invention is applied.

FIG. 9 is a perspective view of another image reading apparatus to which the present invention is applied.

[Explanation of symbols]

 B: Original document D: Automatic document feeder S: Adhesive x: Gap y: Gap 1: Image reading device 2: First mirror table 3: Second mirror table 4: Platen glass 5: Lens 6: CCD sensor 7: Exposure lamp 8 ... Reflection shade 10 ... First mirror 11 ... First mirror base frame 12 ... Guide rail 14 ... Motor 15 ... Frame 16 ... Drive shaft 17 ... Pulley 18 ... Pulley 19 ... Wire 20 ... Wire 21 ... Second Mirror 22 Third mirror 22a Reflecting surface 23 Second mirror base frame 24 Front opening 25 Back opening 26 Projection 27 Projection 28 Projection 29 Plate spring 30 Plate spring DESCRIPTION OF SYMBOLS 31 ... Auxiliary projection part 32 ... Auxiliary projection part 33 ... Front side opening part 34 ... Back side opening part 35 ... Projection part 36 ... Projection part 37 ... Projection part 38 ... Leaf spring 39 ... Leaf spring 40 ... Adjustment piece 41 ... Adjustment piece2 ... Adjustment screw 43 ... Adjustment screw 51 ... Pulley 52 ... Tray 53 ... Discharge tray 54 ... Origin table 101 ... Mirror 101a ... Reflection surface 102 ... Scanning optical unit frame 103 ... Mirror support unit 104 ... Mirror support unit 105 ... Mirror Supporting part 106: leaf spring 107: leaf spring

Claims (13)

[Claims] 1. A platen glass on which a document can be placed, illuminating means for illuminating the document placed on the platen glass, at least one reflection mirror for turning back reflected light from the illuminated document, And a lens for converging the reflected light of (a) and forming an image on an image forming unit, wherein the mirror has a slender, substantially rectangular shape, and the mirror has a reflection surface side. An image reading apparatus, wherein the opposite surface is pressurized and both ends in the longitudinal direction on the reflection surface side are supported by at least two support portions, respectively. 2. A document reading apparatus for reading an image of a document by at least one scanning optical unit moving and scanning a placed document surface, wherein the scanning optical unit is configured to read from an illuminated document. It has at least one reflection mirror that folds the reflected light, and the mirror has an elongated and substantially rectangular shape, and the mirror is pressurized on a surface opposite to the reflection surface side and both sides in the longitudinal direction of the reflection surface side. An image reading apparatus, wherein each end is supported by at least two support portions. 3. The mirror and the support portion are fixed by bonding at least one of at least two support portions at each of both end portions in the longitudinal direction on the reflection surface side of the reflection mirror. The image reading device according to claim 1 or 2, wherein 4. The image reading apparatus according to claim 3, wherein the reflection mirror and the support portion fixed by bonding are bonded with a gap between the reflection mirror and the support portion. . 5. At least one of the at least two support portions at each of the two longitudinal end portions on the reflection surface side of the reflection mirror contacts the reflection surface of the support portion that supports the reflection mirror. The image reading device according to claim 1, wherein a position of a leading end is configured to be adjustable. 6. The at least one of the at least two support portions at each of the two longitudinal end portions on the reflection surface side of the reflection mirror abuts against the reflection surface of the support portion that supports the reflection mirror. 3. The image reading device according to claim 1, wherein the position of the tip is adjustable, and the mirror and the support are fixed by bonding. 7. The image reading apparatus according to claim 6, wherein a gap is provided between the reflection mirror and the tip of the support portion instead of abutting the adjustable support portion against the reflection mirror. 8. A supporting device for a slender, substantially rectangular reflecting mirror, wherein a surface of the reflecting mirror opposite to the reflecting surface is pressed so that both ends in the longitudinal direction of the reflecting surface are at least two points each. A reflection mirror support device, wherein the reflection mirror is supported by a support portion. 9. A supporting device for a slender, substantially rectangular reflecting mirror, wherein the reflecting mirror and the reflecting mirror are provided at at least one of at least two supporting portions at both ends in the longitudinal direction on the reflecting surface side of the reflecting mirror. 9. The reflecting mirror supporting device according to claim 8, wherein the supporting portion is fixed by bonding. 10. The reflection mirror support according to claim 9, wherein the reflection mirror and the support fixed by bonding are adhered with a gap between the reflection mirror and the support. apparatus. 11. At least one of at least two support portions at both end portions in the longitudinal direction on the mirror reflection surface side.
9. The mirror support device according to claim 8, wherein a position of a tip for abutting against a reflection surface of the support portion supporting the reflection mirror can be adjusted by the support portion at each location. 12. At least one of the at least two support portions at each of both ends in the longitudinal direction on the reflection surface side of the reflection mirror abuts against the reflection surface of the support portion that supports the reflection mirror. 12. The reflection mirror supporting device according to claim 11, wherein a position of a tip for adjusting the position of the mirror is configured to be adjustable, and the mirror and the supporting portion are fixed by bonding. 13. The mirror support device according to claim 12, wherein a gap is provided between the adjustable mirror and the reflection mirror instead of abutting the adjustable support against the reflection mirror.