JP2003270734A - Image input device and image forming apparatus equipped therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize an image input device capable of restraining trouble on a reading error or the void of an image caused by a shock due to the omission of a document occurring in the case a curve just before the reading position of a feeding path is sharp in the conventional manner by making the curve gentle with simple constitution and realizing its miniaturization and the reduction of cost, and to realize an image forming apparatus equipped with the image input device. <P>SOLUTION: The image input device G is provided with an image read part 102 capable of reading the image of the document passing through a specified reading position (e) on a platen glass 10 and a document feeding part 101 feeding the document to the specified reading position through the feeding path having curvature nearly from the upper part of the position (e), and is provided with a pair of upstream side feeding rollers 5 arranged near the upstream side of the position (e) in the feeding path, and the center axis of rotation of an upstream side feeding roller 5b being either of the pair of upstream side feeding rollers 5 is arranged. lower than the upper surface of the glass 10. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image input apparatus capable of reading an image while automatically conveying a document and an image forming apparatus including the image input apparatus.

[0002]

2. Description of the Related Art Conventionally, an image reading unit provided in an image input device such as a digital copying machine, a scanner or a facsimile automatically feeds a document as a sheet to the image reading unit. There is an example in which a document feeding unit, which is an example, is provided so as to be freely opened and closed. In the image reading unit, the document automatically fed by the document feeding unit is exposed to read the image of the document.

As such an exposure method, a method of performing an exposure operation by transporting the document onto a platen glass as a reading plane by the document transport unit, temporarily stopping the document, and then moving the exposure device. (Hereinafter referred to as fixed reading), the exposure device is fixed at a position where a predetermined reading position on the platen glass can be read, and
There is a method in which an original is conveyed so as to pass through this predetermined reading position at a predetermined speed and an exposure operation is performed (hereinafter referred to as flow reading). This flow-through reading has an advantage that the document replacement speed can be generally increased as compared with the above-described fixed reading, because it is not necessary to stop the document at the time of reading, and is a technique used in many products. .

FIG. 7 shows a schematic configuration of an image input apparatus as a first conventional example for carrying a document using such a flow-reading technique.

In the conventional image input device shown in FIG. 7, a pair of conveying rollers 202 is provided upstream of a document reading position 201 in the conveying path, and a pair of conveying rollers 203 is provided downstream of the original reading position 201 in the conveying path. A guide member 205 is provided above the reading position 201 to form a minute gap with the platen glass 204. Then, the original is conveyed at a substantially constant speed so as to pass through the reading position 201 within the range of the minute gap between the platen glass 204 and the guide member 205,
The original is being read while minimizing fluctuations in the original speed.

At this time, in order to prevent the original from floating from the platen glass 204, as shown in FIG. 7, a biasing member 206 is provided near the upstream end of the guide member 205 in the conveying direction. As a result, the original can be stably conveyed between the guide member 205 and the platen glass 204, and the quality of the read image is improved.

Here, by arranging the biasing member 206 at a portion of the guide member 205 on the upstream side of the reading position 201, the document to be conveyed is fed to the platen glass 204.
Pressing against.

As a second conventional example, as shown in FIG. 8, a conveying roller pair 202 arranged on the upstream side of the reading position 201 in the conveying path and a reading position 20.
The pressing roller 207, which is arranged between the first and second sheets, presses the conveyed document against the platen glass 204.
There is also an image input apparatus that adopts a configuration in which a guide member 205 ′ is provided in place of the biasing member 206 in the conventional example and near the reading position 201 on the downstream side of the pressing roller 207. The pressing roller 207 here is intended to press the document against the platen glass 204, like the urging member 206 in the first conventional example.

[0009]

However, there are the following problems in the conventional image input device for performing the above-described flow-reading.

When a document is conveyed by a pair of conveying rollers, the pair of conveying rollers, which is composed of a driving roller that generates a driving force and a driven roller that rotates according to the driving roller, must be arranged above the upper surface of the platen glass. Often not. In addition, when scanning the original, it is necessary to keep the original substantially horizontal with respect to the platen glass at the reading position. Therefore, the transport path upstream and downstream of the reading position should have a radius of curvature as large as possible. Is desirable.

In particular, the radius of curvature of the transport path between the transport roller pair 202 and the reading position 201 is preferably as large as possible in order to transport the original substantially horizontally to the platen glass, but the radius of curvature of the transport path is as large as possible. Increasing the radius of curvature often leads to upsizing of the device.

On the other hand, in order to reduce the size of the apparatus, it is preferable that the radius of curvature of the guide shape of the conveying path is as small as possible.
When the radius of curvature of the transport path is set to a small value, when the upstream end of the document in the transport direction (hereinafter referred to as the rear end) passes through the transport rollers or guides and the document that has been guided and bent extends Then, the shock easily occurs due to the original being pulled out, and the behavior of the original while the image is being conveyed and being read may fluctuate, for example, for an instant or late. When a shock occurs due to the document missing, only the part of the image read from the document is enlarged or reduced, that is, a reading error may occur.

Further, when the radius of curvature of the transport path is small, it becomes difficult to transport the document substantially horizontally (flat state) at the reading position, and the surface of the document has a certain angle with respect to the exposure device. If the angle of reflection of light from the document surface is different from the designed angle in this case, the image cannot be read with proper brightness, and the image may appear white in that part. There is.

As in the above-mentioned first and second conventional examples,
An urging member or roller is provided between the transport roller on the upstream side of the reading position on the transport path and the reading position to press the document against the platen glass and transport the document at the reading position so that it is substantially horizontal. By doing so, the problem as described above can be alleviated to some extent, but in the method of disposing the biasing member, the biasing member is caught on the original during the jam processing and is turned up or bent to block the conveyance path. In the worst case, the original may not be conveyed. On the other hand, in the method of arranging the roller, the original cannot be inserted between the nip portion of the roller and the platen glass unless the roller is rotationally driven, that is, unless a drive source for driving the roller is further provided. However, there is a concern that the device configuration will become complicated and that the cost will increase.

The present invention has been made in view of such a problem, and a curve is provided immediately before the reading position of the conveyance path with a simple structure, and a shock due to a document missing which has conventionally occurred when the curve is abrupt. It is an object of the present invention to provide an image input device and an image forming apparatus including the image input device, which can suppress the reading error and the problem of the image being whitened due to the above, and can reduce the size and cost of the device. It is what

[0016]

In order to achieve the above object, in the present invention, an image reading section capable of reading an image of a document passing through a predetermined reading position in a reading plane and an upper portion of the image reading section are provided. In an image input device having an original conveyance unit that is arranged to be openable and closable and that conveys an original document to a predetermined reading position via a conveyance path having a curvature from substantially above the predetermined reading position, in the vicinity of an upstream side of the predetermined reading position Has a pair of transport rollers arranged in
One of the pair of transport rollers is rotatably supported on the image reading unit side, and the other transport roller is rotatably supported on the document transport unit side. The center axis of rotation of the one transport roller is read. It is arranged below the plane.

With this structure, the height difference between the nip portion of the pair of conveying rollers and the reading plane can be reduced, and the conveying path in the vicinity of the upstream of the predetermined reading position can be increased without increasing the size of the apparatus. The radius of curvature can be increased (the curve can be made gentle). As a result, the bending of the document near the upstream side of the reading position is reduced, and the document dropout shock that occurs when the upstream end of the document in the transport direction (hereinafter referred to as the rear end) exits the guide or the transport rollers in the transport path. Can be reduced. Further, it becomes easy to convey the document at the reading position in a state substantially parallel to the reading plane, and it is possible to read the image with proper brightness while keeping the exposure device of the image reading unit and the document substantially parallel. . Further, since it is not necessary to provide a biasing member or roller as shown in the conventional example in order to make the document passing through the predetermined reading position substantially parallel, it is effective in simplifying the drive system, and by extension, in the apparatus. It can contribute to downsizing and cost reduction.

Further, since the curve of the conveying path in the vicinity of the predetermined reading position is gentle, the original can be smoothly conveyed and can be stably conveyed even by a guide having no drive system, which contributes to simplification of the drive system. .

Here, since the document feeding unit is arranged to be openable and closable above the image reading unit, for example, a reading plane is provided on the upper surface side of the image reading unit so that the document can be placed on the document feeding unit. It is possible to read not only the document conveyed by, but also the document placed on the reading plane (for example, a book type document). Further, in this way, the reading plane is provided on the upper surface side of the image reading section, and the document feeding section is arranged on the reading plane, that is, the curve of the feeding path downstream of the predetermined reading position can be made gentle. Even if it is difficult, if the configuration of the present invention is applied on the upstream side of the predetermined reading position of the transport path,
The curve in the vicinity of the upstream side of the predetermined reading position in the transport path can be made gentle, and as a result, the document passing through the predetermined reading position can be easily made substantially parallel to the reading plane.

In addition, a guide member forming an outer peripheral guide surface on the upstream side of the conveying roller pair on the conveying path, and a guide member attached to the inner peripheral guide surface on the upstream side of the conveying roller pair on the conveying path. It may be configured to have a biasing means for biasing, and a spacer means for providing a predetermined space between the guide member and the inner peripheral guide surface, whereby the influence of rattling or the like caused by the use of the device may be eliminated. It is possible to maintain a substantially constant gap (gap) between the outer peripheral guide surface and the inner peripheral guide surface on the upstream side of the pair of conveying rollers in the conveying path without receiving the sheet, and to stably convey the original. it can.

Further, since the curve near the upstream of the predetermined reading position of the transport path is made gentle, the transport resistance at the time of transporting the document in the region upstream of the predetermined read position of the transport path can be reduced, so that the document is transported. Therefore, it is possible to reduce the number of conveying rollers to be installed, which contributes to simplification of the drive system of the apparatus.

Further, the guide member is supported on the image reading portion side so as to be rotatable around the downstream end portion of the conveying path of the guide member, and one conveying roller and the guide member have a rotation center axis. May be shared. In this way, the configuration in which one of the transport rollers and the central axis of rotation of the guide member are commonly used can contribute to simplification of the apparatus configuration.

The conveying roller pair is composed of a pair of a driving roller which generates a driving force and a driven roller which rotates in accordance with the driving roller, and one conveying roller rotatably supported on the image reading side is a driven roller. With a certain configuration, it is not necessary to provide a drive source dedicated to the drive roller by sharing the motor used for document transportation, etc., which is provided in the document transport section, as a drive source, so that the apparatus can be downsized and the cost can be reduced. Can contribute to. Further, since the driven roller does not require a drive source and has a high degree of freedom in design even when it is arranged in a narrow space, it is easy to arrange the rotation center axis below the reading plane.

A press contacting means for pressing an original document passing through a predetermined reading position against the reading plane is provided, and the pressing means has a white flat portion opposed to the reading plane at a predetermined interval. May be
It may have a roller arranged so as to be in pressure contact with the reading plane and having a white roller surface.

According to this, the portion of the document that passes near the predetermined reading position can be made substantially parallel to the reading plane, and the part facing the reading plane is white, so that An image with high fidelity and high contrast can be read.

In addition, an image forming apparatus having the above-described image input apparatus and an image forming section for forming an image on a sheet based on image information read from a document by the image input apparatus may be formed. It is possible.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIG. 1 is a schematic view of an image input device G according to a first embodiment of the present invention, and FIG. 2 is a sectional view of a document feeding portion 101 of the image input device G. Shows.

As shown in FIG. 1, the image input apparatus G in this embodiment has a document feeding section 101 and an image reading section 102. A document feeding unit 101 having a function as an ADF capable of automatically feeding a document is openably and closably connected to an upper portion of an image reading unit 102 via a hinge unit 104, and a predetermined reading position e of the image reading unit 102. The original is conveyed to. The image reading unit 102 includes a platen glass 10 as a reading plane arranged on the upper surface side and a jump base 11,
The exposure device 1 arranged below the platen glass 10.
03, the exposure device 103 performs the exposure operation of the document conveyed from the document conveyance unit 101, and the platen glass 1
It is possible to read the image of the original document that passes the predetermined reading position e above 0.

Next, referring to FIG. 3, the original feeding section 101 and the image reading section 102 of the image input apparatus G according to the present embodiment.
The configuration in the vicinity of the predetermined reading position e will be described.

The image input device G is provided with a conveyance path having a curvature from substantially above a predetermined reading position e on the platen glass 10, and a document is read from the stack tray 1 to a predetermined reading position via the conveyance path. The document is conveyed by the document conveying unit 101 to e.

Here, in the vicinity of the upstream side of the predetermined reading position e in this conveying path and on the downstream side of the registration roller pair 4, an upstream conveying roller pair 5 composed of upstream conveying rollers 5a and 5b is arranged, A downstream side transport roller pair 7 including downstream side transport rollers 7a and 7b is arranged in the vicinity of the downstream side of the predetermined reading position e in the transport path.

The registration roller pair 4 composed of the registration rollers 4a and 4b has a function of correcting the conveyance timing and skew before the document is sent to the upstream side conveyance roller pair 5.

Of the pair of transport rollers forming the upstream transport roller pair 5, the upstream transport roller 5a as the other transport roller is rotatably supported on the document transport unit 101 side.
The upstream transport roller 5b as one transport roller is rotatably supported on the image reading unit 102 side. At this time, as shown in FIG. 3, the height position of the rotation center axis of the upstream side conveyance roller 5b is the height position Z of the upper surface of the platen glass 10.
Is arranged below by a predetermined dimension x. With such an arrangement, the height position of the nip portion of the upstream side transport roller pair 5 and the height position of the upper surface of the platen glass 10 are substantially the same. Of course, not limited to this, the height position of the nip portion of the upstream side transport roller pair 5 may be slightly higher than the height position of the upper surface of the platen glass 10.

The pair of conveying rollers is composed of a pair of a driving roller that generates a driving force and a driven roller (driven roller) that rotates according to the driving roller. Here, the upstream side is arranged on the side of the original conveying section 101. The side conveying roller 5a is a driving roller, and the upstream side conveying roller 5b arranged on the image reading unit 102 side is a driven roller.

With such a structure, it is necessary to provide a drive source dedicated to the drive roller by sharing the motor provided in the document transport section 101 for use in document transport and the like as the drive source on the drive roller side. Since it is eliminated, it can contribute to downsizing and cost reduction of the device. Further, the driven roller does not require a drive source, can be arranged in a small space, and has a high degree of freedom in design, and as a result, the height position of the rotation center axis of the upstream side conveying roller 5b is higher than that of the platen glass. Also has the effect that it can be easily arranged below.

The image input device G has a predetermined reading position e.
It has a platen roller 6 as a pressure contact means for pressing a document passing through the platen glass 10 as a reading plane, and the platen roller 6 is arranged so as to be in pressure contact with the platen glass 10. The roller surface is white.

By doing so, the portion of the document that passes near the predetermined reading position can be made more parallel to the reading plane, and since the roller surface is white, the original document is used. High-contrast image reading that is true to

Further, the upstream transport rollers 5a in the transport path,
5b, a lower guide 13 serving as a guide member forming an outer peripheral guide surface upstream of 5b, and an upper guide serving as the inner guide surface of the lower guide 13 upstream of the upstream conveying roller pair 5 in the conveying path. Biasing means 16 composed of a spring or the like for urging against 12, a lower guide 13 and an upper guide 12
And an abutting member 17 as a spacer means for leaving a predetermined space therebetween. As illustrated, the upstream guide roller 5a is provided on the upper guide 12 side.
However, the upstream transport roller 5b is arranged on the lower guide 13 side.

As shown in the figure, the upper guide 12 is provided on the original conveying section 101 side and the lower guide 13 is provided on the image reading section 102 side, and the guide surface shape of the lower guide 13 follows the upper guide 12. It has a curved shape.

The lower guide 13 is supported by the image reading unit 102 by the support shaft 15 so as to be rotatable around the downstream end of the lower guide 13 in the conveying path, and the lower guide 13 is upstream. Conveyor roller 5b and lower guide 1
3 and 3, the support shaft 15 as a rotation center shaft is shared.

In this way, by making the rotation center axis of the upstream side conveying roller 5b and the lower side guide 13 common, it is possible to contribute to simplification of the apparatus structure.

The abutting member 17 is provided at a predetermined position other than the area of the upper guide 12 for guiding the original,
When the document conveying unit 101 is closed with respect to the image reading unit 102, by colliding with a predetermined position (that is, a position facing the arrangement position of the abutting member 17) of the lower guide 13 other than the region for guiding the document, The lower guide 13 and the upper guide 12 can always keep a substantially constant interval. That is, for example, even if backlash or the like occurs due to the use of the apparatus, the interval (gap) between the lower guide 13 and the upper guide 12 on the upstream side of the upstream transport roller pair 5 in the transport path is always substantially constant. It becomes possible to keep the original, and the original can be stably conveyed.

In this embodiment, the abutting member 17
Is configured to be arranged at a predetermined position other than the area of the upper guide 12 for guiding the document, but the present invention is not limited to this, and by arranging the abutting member 17 on the lower guide 13 side, The distance between the side guide 13 and the upper guide 12 can be kept substantially constant, and the same effect as that of the above configuration can be obtained.

Further, since the curve near the upstream of the predetermined reading position e in the transport path is made gentle, the transport resistance at the time of transporting the document in the region upstream of the predetermined read position e in the transport path can be reduced. It is possible to reduce the number of installations of the transfer rollers for transferring the sheet, as compared with the conventional installation, which can contribute to simplification of the drive system of the apparatus.

Next, with reference to FIGS. 4 and 5, a method of positioning the document feeding section 101 and the image reading section 102 in this embodiment will be described in detail. 4 shows the configuration of the hinge unit 104, and FIG. 5 shows the configuration of the image reading unit.

A document feeder 101 having a function as an ADF capable of automatically feeding a document is openably and closably connected to an upper portion of an image reading unit 102 via a hinge 104. At this time, the foot 104a of the hinge portion 104 is inserted into the hinge holes 21 and 22 (see FIG. 5) formed in the upper portion of the image reading apparatus 102. A play is provided between the leg 104a of the hinge unit 104 and the hinge holes 21 and 22, and a positioning pin 23 (see FIG. 1) provided on the front side of the document conveying unit 101 is an image reading unit described later. By being inserted into the positioning hole 20 of 102, positioning between the document conveying section 101 and the image reading section 102 is performed. The positioning pin 23 is provided so as to be located coaxially with the rotation axis of the upstream side transport roller 5a, and the positioning hole 20 is provided coaxially with the rotation axis of the upstream side transport roller 5b. The positioning accuracy between the upstream side transport roller 5a and the upstream side transport roller 5b is maintained.

The support shaft 15 for supporting the upstream side transport roller 5b provided in the image reading section 102 is supported at both ends by a rotation fulcrum 18 and a position adjusting plate 19. As a result, the support shaft 15 is rotatable about the rotation fulcrum 18 in the direction of the arrow in the figure, and the amount of rotation is adjusted by the position adjusting plate 19 and fixed. Further, the position adjusting plate 19 is provided with a positioning hole 20 coaxially with the support shaft 15, and the positioning pin 23 is inserted therein. Accordingly, by finely adjusting the support shaft 15 to be parallel to the exposure device 103, it is possible to maintain the parallelism between the document conveying unit 101 and the image reading unit 102 with high accuracy without adjusting after assembling. Yes, further upstream transport roller 5a
It is also possible to accurately maintain the nip position between the upstream side transport roller 5b and the upstream side transport roller 5b.

As described above, by easing the curve immediately before the predetermined reading position on the transport path with a simple structure, the adverse effect that has been conventionally caused when this curve is steep is suppressed, and the apparatus is miniaturized. Further, it is possible to realize an image input device capable of achieving cost reduction.

Next, a method of conveying an original when only one side of the original is read by the image input apparatus G according to the present embodiment will be described.

First, the feeding tray 1 of the document stacking unit A
Load the original on top.

In the document transport unit B, the pickup roller 2 draws the document bundle stacked on the feed tray 1 into the feed roller 3a and the friction separating pad 3b which form the separating section, so that the document stack is placed at the highest position. The originals are separated one by one and conveyed to the registration roller pair 4.

The registration roller pair 4 is stopped at the arrival of the downstream end (hereinafter referred to as the leading end) of the original in the conveying direction, and is conveyed by the feeding roller 3a to form a loop for skew correction, and then the original is conveyed. Is transported to the upstream transport roller pair 5.

The upstream conveying roller pair 5 conveys the fed original document toward the downstream conveying roller pair 7 through the minute gap between the platen roller 6 and the platen glass 10.

During a series of conveying operations in which the original is conveyed from the upstream side conveying roller pair 5 to the downstream side conveying roller pair 7, the original is nipped by the upstream side conveying roller pair 5 and the downstream side conveying roller pair 7. Is conveyed at a predetermined speed on the reading position e, the exposure operation is performed by the exposure device 103 located below the reading position e of the platen glass 10, and the image of the original is read by the image reading unit 102.

The document discharged from the downstream conveying roller pair 7 is guided to the discharge rollers 8a and 8b of the document discharging unit C.

In the document discharge unit C, the reading position e
While the exposure operation is being performed, the discharge roller 8b moves downward, the discharge rollers 8a and 8b are separated from each other, and the transport operation is not performed. Then, when the trailing edge of the document passes the reading position e and the reading is completed, the discharge roller 8b is moved upward,
The document is placed between the discharge rollers 8a and 8b so as to be sandwiched, and is discharged onto the discharge tray 9 of the discharge stacking unit D with the reading surface of the document facing downward (reverse side discharge).
To do.

Next, a method of conveying an original when reading both sides of the original in the image input apparatus G according to the present embodiment will be described.

First, the feeding tray 1 of the document stacking unit A
The originals stacked on the upper side are separated one by one by the original conveying unit B and are conveyed to the reading position e on the platen glass 10 as in the case of reading only one side described above.

A document passing above the reading position e is
As with the case of reading only one side, the upstream side transport roller pair 5
It is nipped by the downstream conveying roller pair 7 and is conveyed between the platen glass 10 and the platen roller 6 at a predetermined speed.

Similar to the case of reading only one side, the image on one side of the original is read by the exposure device 103 located below the reading position e and stored in a storage unit (not shown).

Next, in the document discharge unit C, after the trailing edge of the document passes the discharge sensor S1, the discharge rollers 8a and 8b are reversed, and the document is conveyed to the discharge tray 9 in the direction opposite to the discharge direction. Then, the original is switched back to the registration roller pair 4 in the original conveying unit B by re-entering the conveying path through the switchback path S in which the flapper 18 is arranged.

Then, the registration roller pair 4 which again sandwiches the switched-back original document conveys the original document to the reading position e on the platen glass 10, and in the same manner as when one side is read, the upstream side conveyance roller pair. 5 and the downstream side transport roller pair 7 transport the sheet at a predetermined speed to perform an exposure operation on the other surface, and guide the sheet to the document discharge unit C.

Due to the structure of the document conveying section 101 of this embodiment,
When reading both sides of a document, if the document discharge unit C discharges the document as it is after reading the other side (second side), the discharged document faces upward when it is placed on the feed tray 1. When one side is placed on the discharge tray 9, the other side faces downward (face-up), and the stacking order of the originals is disturbed. Therefore, the other side is read to correct the original order. It is necessary to invert the front and back sides of the original after retouching.

Therefore, in the document discharge unit C,
After the trailing edge of the document after the second side has been read passes the discharge sensor S1, the discharge rollers 8a and 8b are reversed, and the document is transferred back to the registration roller pair 4 again by switchback conveyance as in the case of reading both sides of the document. The document is conveyed, inverted, and discharged onto the discharge tray 9 of the discharge stacking unit D.

(Second Embodiment) Next, an image input apparatus according to a second embodiment of the present invention will be described.

The present embodiment is an application of the above-described first embodiment, and is different from the image input device according to the first embodiment in the configuration in the vicinity of the predetermined reading position e. Hereinafter, the same parts as those described above are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 6, in the image input device G ′ according to the present embodiment, the platen roller 6 as the pressure contact means arranged near the predetermined reading position e on the platen glass 10 in the first embodiment described above. Instead of,
The platen glass 10 serving as a reading plane is configured to use a guide plate 14 having a white plane portion facing the platen glass 10 at a predetermined interval. The guide plate 14 presses the document passing through the predetermined reading position e against the platen glass 10.

According to this, the portion of the document that passes near the predetermined reading position can be made substantially parallel to the reading plane, and the portion facing the reading plane is white, so An image with high fidelity and high contrast can be read. In addition, the color of the roller guide plate 14 will not be transparently read when the document is read.

In each of the above-described embodiments, the configuration of the transport roller pair on the upstream side of the predetermined reading position e on the transport path is taken as an example, but a similar configuration is provided on the downstream side of the predetermined reading position e on the transport path. It is also possible to apply to the pair of conveying rollers on the side.

Further, as the original used in the image input apparatus according to each of the above-described embodiments, for example, ordinary copy paper, printer paper, ink jet paper (including glossy paper), OHP sheet, etc. can be applied. is there.

In addition, the configuration is not limited to the above-described configuration, and for example, the transport rollers 5a and 5b arranged upstream of the predetermined reading position e are both the image reading unit 102.
It may be arranged on the side. With such a configuration, it is possible to maintain the positional relationship of the nip portion between the transport roller 5a and the transport roller 5b with high accuracy,
The document can be conveyed more stably.

The image input apparatus according to each of the above-described embodiments can be applied to any device (for example, a scanner) that automatically conveys a document and reads the image of the document. The effect of the present invention is exerted by configuring an image forming apparatus that includes the image input apparatus according to the embodiment and an image forming unit that forms an image on a sheet based on image information read from a document by the image input apparatus. It is possible to provide an image forming apparatus that can do this.

When the device to which the image input apparatus according to the present embodiment is applied is a scanner, the scanner is not limited to a scanner having a structure capable of opening and closing the document feeding unit and the image reading unit, and for example, the document feeding unit and the image reading unit. Are integrally configured, and can be applied to a scanner configured to only read an original document automatically conveyed by the original document conveying section by the image reading section.

As described above, according to the above-described embodiments, the height difference between the nip portion of the conveying roller pair and the reading plane can be reduced, and the predetermined reading can be performed without increasing the size of the apparatus. Increase the radius of curvature of the transport path near the upstream position (make the curve gentle)
be able to. As a result, the bending of the document in the vicinity of the upstream side of the predetermined reading position is also reduced, and the document comes out when the upstream end of the document in the transport direction (hereinafter referred to as the rear end) exits the guide or the transport roller in the transport path. It can reduce shock. Further, it becomes easy to convey the document at the reading position in a state substantially parallel to the reading plane, and it is possible to read the image with proper brightness while keeping the exposure device of the image reading unit and the document substantially parallel. .

Further, since it is not necessary to provide the biasing member 206 and the roller 207 as shown in the conventional example in order to make the document passing through the predetermined reading position substantially parallel, it is effective in simplifying the drive system. Further, it can contribute to downsizing and cost reduction of the device.

Further, since the curve of the conveying path in the vicinity of the predetermined reading position is gentle, the original can be smoothly conveyed, and it is not necessary to provide a drive system for conveying the original to the pressure contact means, and stable original conveyance can be realized. It can contribute to simplification and cost reduction of the drive system.

As in the above-described embodiments, the document conveying section is arranged above the image reading section so as to be openable and closable, so that, for example, a reading plane is provided on the upper surface side of the image reading section, and a book document or the like is provided. Of the exposure apparatus 103, which is placed below the platen glass 10 at the reading position e shown in each of the above-described embodiments.
Is configured to be movable and scannable in a predetermined direction, so that not only a document conveyed by the document conveying section but also a document placed on a reading plane (for example, a book type document) can be read. it can.

Further, as described above, the reading plane is provided on the upper surface side of the image reading section, and the document feeding section is arranged on the reading plane, that is, the curve of the feeding path downstream from the predetermined reading position is made gentle. Even if it is difficult to do so, by applying the configuration of the present invention to the upstream side of the predetermined reading position of the transport path, the curve near the upstream side of the predetermined reading position of the transport path can be made gentle.

[0079]

As described above, according to the inventions of the present application, the curve immediately before the reading position of the conveying path is made gentle by a simple structure, and the shock caused by the document missing which has been conventionally generated when the curve is steep. It is possible to realize an image input apparatus and an image forming apparatus including the image input apparatus, which can suppress the reading error and the problem of the image being whitened due to the above, and can reduce the size and cost of the apparatus. .

[Brief description of drawings]

FIG. 1 is a schematic diagram of an image input device according to a first embodiment of the present invention.

FIG. 2 is a sectional view of the image input device according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view (platen roller) showing details in the vicinity of a predetermined reading position of the image input apparatus according to the first embodiment of the present invention.

FIG. 4 is a diagram for explaining a method of positioning a document feeding unit and an image reading unit.

FIG. 5 is a diagram for explaining a method of positioning a document feeding unit and an image reading unit.

FIG. 6 is a cross-sectional view (guide plate) showing details in the vicinity of a predetermined reading position of the image input apparatus according to the second embodiment of the present invention.

FIG. 7 is a diagram for explaining a configuration near a predetermined reading position of an image input apparatus as a first conventional example.

FIG. 8 is a diagram for explaining a configuration near a predetermined reading position of an image input device as a second conventional example.

[Explanation of symbols]

101 document transport section 102 image reading unit 103 exposure device 104 Hinge part 104a Hinge foot 201 reading position 202 Conveyor roller pair (upstream side) 203 Conveyor roller (downstream side) 204 platen glass 205 Guide member 206 biasing member 207 Pressing roller A Document loading unit B Document transport unit C Document ejection unit D discharge loading unit S1 emission sensor 1 loading tray 2 pickup roller 3a Feed roller 3b Friction separating pad 4 Pair of registration rollers 4a Registration roller 4b Registration roller 5 Upstream transport roller pair 5a Upstream transport roller 5b upstream transport roller 6 Platen roller 7 Downstream transport roller pair 7a Downstream transport roller 7b Downstream transport roller 8a discharge roller 8b discharge roller 9 Ejection tray 10 Platen glass 11 jump stand 12 Upper guide 13 Lower guide 14 Guide plate 15 Support shaft 16 Biasing means 17 Abutting member 18 rotation fulcrum 19 Position adjustment version 20 Positioning hole 21 Hinge hole 22 Hinge hole 23 Positioning pin

Claims (5)

[Claims] 1. An image reading unit capable of reading an image of a document passing through a predetermined reading position in a reading plane, and an openable and closable arrangement above the image reading unit, and a curvature is provided from substantially above the predetermined reading position. An image input device having an original document transport section for transporting an original document to the predetermined reading position via a transport path which has a transport roller pair arranged near an upstream side of the predetermined reading position in the transport path, One of the pair of transport rollers is rotatably supported on the side of the image reading unit, and the other transport roller is rotatably supported on the side of the document transport unit. Is arranged below the reading plane. 2. A guide member forming an outer peripheral guide surface on the upstream side of the conveying roller pair on the conveying path, and the guide member on an inner peripheral guide surface on the upstream side of the conveying roller pair on the conveying path. The image input device according to claim 1, further comprising: a biasing unit that biases the guide member and a spacer unit that forms a predetermined space between the guide member and the inner peripheral guide surface. 3. The guide member is supported on the side of the image reading unit so as to be rotatable around an end portion on the downstream side of a conveying path of the guide member, and the one conveying roller and the guide member are provided. 3. The image input device according to claim 2, wherein the image input device shares a central axis of rotation. 4. The pair of conveying rollers comprises a pair of a driving roller that generates a driving force and a driven roller that rotates according to the driving roller, and the one conveying roller is a driven roller. The image input device according to any one of 1 to 3. 5. An image input device according to claim 1, and an image forming unit for forming an image on a sheet based on image information read from an original by the image input device. Image forming apparatus.