JP2006319770A - Image reading apparatus and image forming apparatus employing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image reading apparatus easily reading both sides of an original through the use of a single imaging section without upsizing the structure, making the structure complicated and causing any jamming and any damages to the original, and also to provide an image forming apparatus employing the image reading apparatus. <P>SOLUTION: In the image reading apparatus 50, an original carrying path 1 is curvedly formed from a paper feed stack part 2 located at an upper end part in the middle of the image reading apparatus toward a paper discharge stack part 3 obliquely downwardly located in a part of the stack part 2 and carries in one way a sheet original M on both front and rear sides of which characters or the like being image reading objects are displayed. Two read sections 10, 20 for reading the front side and rear side of the original M are respectively arranged in the middle part of the original carrying path 1. The image reading apparatus 50 includes an optical connection part 30 for optically interconnecting both the read sections 10, 20 and the single imaging section 40 located in a way of facing the one read section 10. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image reading apparatus, and more particularly to an image reading apparatus capable of reading images on both sides of a document, and an image forming apparatus using the image reading apparatus.

  2. Description of the Related Art Conventionally, when reading both sides of a sheet-like document in an image reading apparatus such as a copying machine or a printing machine, the image reading unit (inverts the front and back of the document in the middle of the document transport path from the document supply unit to the document discharge unit ( In general, the imaging section is passed twice (see FIG. 8 of Patent Document 1). However, since the image reading apparatus requires a reversing mechanism, the structure is likely to be large and complicated, and the document reading time is relatively long. Further, there is a high possibility that the document is jammed or damaged in the reversing mechanism.

  Therefore, it has been proposed to provide two image pickup units (image sensors) so that both the front and back sides of the document can be read separately (see FIGS. 2, 5, and 6 of Patent Document 1). According to such an image reading apparatus, the document reading time can be shortened, but it is expensive because it requires two imaging units, and the entire document transport path and the entire imaging unit are further increased due to the arrangement of the two imaging units. There is a risk of increasing size and complexity.

JP 2002-101267 A

  SUMMARY OF THE INVENTION An object of the present invention is to reduce the size and simplify the structure and to easily read both sides of a document with a single image pickup unit without causing clogging or damage of the document, and its image reading An object of the present invention is to provide an image forming apparatus using the apparatus.

Means for Solving the Problems and Effects of the Invention

In order to solve the above problems, an image reading apparatus according to the present invention provides:
The first transport unit extending in a predetermined direction, the direction changing unit connected to the front end side of the first transport unit and changing the direction, and the first transport unit connected to the front end side of the direction converting unit And a second conveying section extending in the opposite direction, and a sheet-like document to be read by the image is sequentially passed from the document feeding section to the first conveying section, the direction changing section, and the second conveying section toward the document discharging section. A document conveyance path for unilateral conveyance;
A first image reading unit disposed on the first conveyance unit of the document conveyance path for reading a first document surface that is one of the front and back surfaces of the document;
The second document surface of the document conveyance path spaced a predetermined distance downstream from the first image reading unit is arranged to read the second document surface opposite to the first document surface of the document. A second image reading unit provided;
A light propagation unit that optically connects the first and second image reading units so that light propagation between the first and second image reading units is possible in a form in which the respective optical axes coincide with each other;
One of the first and second image reading units is disposed directly opposite to the one image reading unit, and the one image reading unit and the light propagation with respect to the other image reading unit In each image reading unit, light is emitted from the light source toward the document surface of the document that is continuously or intermittently sent along the conveyance direction. A single imaging unit that reads and converts an image obtained by forming an image of the reflected light reflected by the original surface into an electrical signal;
First, in the first image reading unit on the upstream side, light from the light source of the imaging unit is irradiated onto the first document surface, and an image of reflected light reflected by the first document surface is the imaging unit. Read in
Thereafter, in the second image reading unit on the downstream side, light is emitted from the light source of the imaging unit to the second document surface, and an image of reflected light reflected by the second document surface is obtained by the imaging unit. It is read.

In order to solve the above problems, the image reading apparatus of the present invention is
The first transport unit extending in a predetermined direction, the direction changing unit connected to the front end side of the first transport unit and changing the direction, and the first transport unit connected to the front end side of the direction converting unit And a second conveying section extending in the opposite direction, and a sheet-like document to be read by the image is sequentially passed from the document feeding section to the first conveying section, the direction changing section, and the second conveying section toward the document discharging section. A document conveyance path for unilateral conveyance;
A first image reading unit disposed in the first conveying unit of the document conveying path for reading an image displayed on a first document surface which is one of the front and back surfaces of the document;
The image displayed on the second document surface on the opposite side of the first document surface of the document on the second transport unit of the document transport path spaced a predetermined distance downstream from the first image reading unit. A second image reading unit arranged to read
A light propagation unit that optically connects the first and second image reading units in a straight line so that light propagation between the first and second image reading units is possible in a form in which the respective optical axes coincide with each other;
It is disposed directly opposite to the first image reading unit, and indirectly opposed to the second image reading unit via the first image reading unit and the light propagation unit. In each image reading unit, light is emitted from a light source toward the document surface of the document that is continuously or intermittently sent along the conveyance direction, and reflected light reflected by the document surface is reflected. A single imaging unit that reads and converts an image obtained by imaging into an electrical signal;
First, in the first image reading unit on the upstream side, light from the light source of the imaging unit is irradiated onto the first document surface, and an image of reflected light reflected by the first document surface is the imaging unit. Read in
Thereafter, the second image reading unit on the downstream side irradiates light from the light source of the imaging unit to the second document surface through the first image reading unit and the light propagation unit in a straight line, The reflected light image reflected from the second document surface is read by the imaging unit through the light propagation unit and the first image reading unit in a straight line.

  According to these image reading apparatuses, the first and second image reading units are arranged in the first conveying unit and the second conveying unit, and these image reading units are optically connected (for example, in a straight line). What is necessary is just to provide a light propagation part and a single imaging part. For this reason, it is not necessary to arrange a reflecting mirror for optical connection between the image reading units in the light propagation unit, and the image reading for double-sided originals can be performed on a copying machine, a printing machine, etc. while miniaturizing and simplifying the structure. The device can be easily incorporated. In addition, since these image reading units are arranged in the middle of the document conveyance path for unilaterally conveying the document from the document supply unit to the document discharge unit, the structure can be simplified without requiring a document reversing mechanism. At the same time, it is possible to easily read both sides of the document while preventing the document reading unit from being clogged or damaged. A flexible light propagation member such as an optical fiber may be used for the light propagation portion.

  Here, the “document” is a sheet-like paper sheet on which characters, numbers, symbols, drawings, pictures, photographs, etc. are displayed (described) on the front and back document surfaces (first and second document surfaces) by printing or the like. Refers to a kind. Therefore, the imaging unit can display images (optical images) of characters and the like by forming an image of the reflected light reflected from the document surface, and can read the image by converting it into an electrical signal by the image sensor (image sensor). .

So, for example,
When a document is present in the first image reading unit located on the upstream side, the light emitted from the light source is reflected by the first document surface of the document and read by the imaging unit,
When there is no document in the first image reading unit located on the upstream side and there is a document in the second image reading unit located on the downstream side, the light emitted from the light source is the first image reading unit and The light propagating portion passes through the light propagating portion in a straight line and is reflected by the second manuscript surface of the manuscript, and passes through the light propagating portion and the first image reading portion in a straight line and is read by the imaging portion.

  In this way, by alternately reading images with the first and second image reading units arranged in a straight line, the front surface of the first document → the back surface of the first document → the front surface of the second document → The back side of the second original can be scanned continuously as in the case of .fwdarw...., And the original reading time can be shortened.

  In these image reading apparatuses, it is desirable that the separation distance along the document conveyance path between the first and second image reading units is set to be longer than the length of the document in the document conveyance path direction. That is, when the conveyance distance between the first and second image reading units is equal to or longer than the document length in the document conveyance path direction, the second image reading unit reads the image. Since the end of the document does not block the first image reading unit, it is easy to read images alternately between the first and second image reading units.

  In addition, the first transport unit and the second transport unit are arranged vertically so as to be parallel to each other, and the light emitted from the light source of the imaging unit is the first and second image reading units. It can irradiate so that it may become orthogonal with respect to the original surface of the original located in position. As a result, the document conveyance path can be formed into a hairpin curve shape (slurry folded shape) such as a flat S-shape or a flat horizontal U-shape, so that the vertical height of the document conveyance path and the entire image reading apparatus can be kept low. Thus, the structure can be simplified, the reading of each original surface is stabilized, and accurate image data can be obtained.

  Further, the imaging unit includes a solid-state image sensor on an imaging surface corresponding to the first document surface of the document positioned at the first image reading unit or the second document surface of the document positioned at the second image reading unit. A focus adjustment mechanism for performing focusing so that the light receiving surfaces of the image sensors coincide with each other can be included. Accordingly, when the first and second image reading units alternately perform image reading, it is only necessary to perform focusing (focusing) by the focus adjustment mechanism, so that it is possible to shorten the document reading time. .

  A solid-state imaging device or a solid-state imaging tube is used as an “image sensor” that converts an image (optical image) into an electrical signal. Among these, the solid-state imaging device includes a linear sensor (one-dimensional) and an image sensor or an area sensor (two-dimensional). Further, as an image sensor type solid-state imaging device, a CCD (charge coupled device), a CPD (charge priming device), a MOS (metal oxide semiconductor) type, a CID (charge injection device) or the like is used. be able to.

  When a document is present in one of the first and second image reading units, the other image reading unit is allowed to carry in another document until reading of a predetermined document surface is completed in the image reading unit. If prohibited, the alternate image reading in the first and second image reading units is performed smoothly, and the document reading time can be further shortened.

by the way,
There is provided a reading control unit capable of selectively inputting which of the front and back sides of the document is to be scanned.
Based on the selection input, the reading control unit allows the image reading unit corresponding to the selected document surface of the first and second image reading units to pass the document while reading the document surface and is selected. An image reading unit corresponding to a non-original surface can be controlled to pass the original without reading the original surface.

  As a result, when a so-called single-sided reading mode is selected and input, for example, the original document is printed only on one side of the document, or the original document is printed on both sides of the document and only one side of the document needs to be scanned. Is transported on the same document transport path as in the case of duplex scanning. Therefore, since it is not necessary to provide a document conveyance path and an imaging unit different from those for double-sided scanning for single-sided scanning, it is possible to prevent an increase in size and complexity of the structure of the image reading device.

Or
In the vicinity of the first image reading unit, a document surface that is bound and held on the upper surface of the transparent portion is placed on a transparent portion (for example, a glass plate) as a manually placed original on a bound document. A third image reading unit is provided for reading,
The image capturing unit moves continuously or intermittently along the transparent portion at a position facing the third image reading unit, while facing the original surface of the manually placed document held on the transparent portion. An image obtained by irradiating light from a light source and forming an image of reflected light reflected from the original surface may be converted into an electrical signal and read.

  By additionally using the above-described imaging unit, it is possible to easily read an image of a manually placed document in the third image reading unit, so that the function can be performed as a so-called manual reading mode without increasing the size and complexity of the structure. Can be added.

Next, in order to solve the above-described problem, the image forming apparatus of the present invention includes:
The image reading apparatus is provided, and an image is formed on a recording material based on a result of image reading of a document by the image reading apparatus.

  In this way, the image data can be formed (for example, transferred) on the recording material using the image data on both sides of the document read by the image reading device (imaging unit). Without increasing the size and complexity. The “recording material” includes OHP sheet material and the like in addition to paper sheets such as copy paper (quality paper) and cardboard.

Example 1
Hereinafter, embodiments of the present invention will be described with reference to examples shown in the drawings. FIG. 1 is a schematic explanatory view showing an example of a copying machine as an image forming apparatus according to the present invention. As shown in FIG. 1, an image reading device 50 that is a main part of the present invention is provided at the top of the copying machine 100. The image reading apparatus 50 includes a document transport path 1 from a sheet feed stack unit 2 (document supply unit) positioned at the upper end of the center toward a sheet discharge stack unit 3 (document output unit) positioned obliquely below the sheet stack unit 2. A sheet-like document M that is formed in a curved shape (curved shape) on which characters and the like to be read are displayed (described) on both front and back surfaces is conveyed in one way. Two reading units 10 and 20 (first and second image reading units) are disposed in the middle of the document transport path 1 in order to read both sides of the document M. The image reading apparatus 50 is disposed so as to face (directly face) one optical unit 30 (light propagation unit) that optically connects both the reading units 10 and 20 and one reading unit 10. A single imaging unit 40.

  Also, below the image reading device 50, an image forming unit 60 that forms a toner image (image) on a transfer paper P (copy paper; recording material), and a transfer that feeds the transfer paper P to the image forming unit 60. A paper transport unit 70 and a transfer paper discharge unit 80 for discharging the transfer paper P on which the toner image is formed by the image forming unit 60 to the outside of the copying machine are provided. Specifically, the image forming unit 60 controls the laser beam emitted from the semiconductor laser 61 based on the image data of the document M that is read by being converted into an electrical signal by the imaging unit 40, and is applied to the photosensitive drum 62. After the electrostatic latent image is formed, toner is attached to the electrostatic latent image by the developing unit 63 to visualize it. Then, the toner is transferred onto the transfer paper P fed from the transfer paper transport unit 70 to form a toner image on the transfer paper P surface. Thereafter, the transfer paper P is fixed to the toner transferred through the fixing unit 64 and discharged to a transfer paper discharge unit 80 outside the copying machine via a plurality of pairs of guide rollers 81.

  FIG. 2 is an explanatory view showing an example of an image reading apparatus according to the present invention. As shown in FIG. 2, the curved document transport path 1 is specifically formed as follows. The document conveyance path 1 includes a carry-in portion 102 that is inclined downward from the paper feed stack portion 2 to one end side (for example, the left side), and a first that extends substantially horizontally from the lower end of the carry-in portion 102 to the other end side (for example, the right side). The conveyance unit 111, a first direction conversion unit 112 (direction conversion unit) that converts (inverts) the direction at the front end of the first conveyance unit 111, and from the front end of the first direction conversion unit 112 to one end side (for example, the left side). The second conveyance unit 121 that returns to the horizontal state, the second direction conversion unit 122 (direction conversion unit) that changes (inverts) the direction at the tip of the second conveyance unit 121, and the other end from the tip of the second direction conversion unit 122 A carry-out unit 103 connected in a substantially horizontal manner to the discharge stack unit 3 on the lower side (for example, the right side) is sequentially (continuously) connected and configured.

  A front side reading unit 10 (first image reading unit) is disposed in the intermediate portion of the first transport unit 111 to read the front side document surface M1 (first document surface) of the document M. A back side reading unit 20 (second image reading unit) is disposed at the leading end of the conveyance unit 121 in order to read the back side document surface M2 (second document surface) of the document M. And the 1st conveyance part 111, the 1st direction conversion part 112, the 2nd conveyance part 121, the 2nd direction conversion part 122, and the carry-out part 103 are flat S-shape (hairpin curve shape; a zigzag shape) as a whole. Is formed. Moreover, the 1st conveyance part 111 and the 2nd conveyance part 121 are arrange | positioned up and down so that it may become substantially parallel mutually. As described above, since the document conveyance path 1 is formed in a flat S-shape and the both conveyance portions 111 and 121 are arranged vertically in parallel, the structure (particularly the vertical structure) is reduced in size and simplified. be able to.

  Between the paper feed stack unit 2 and the carry-in unit 102, a supply mechanism 102a (for example, a separation belt and a separation roller positioned opposite to each other with the document M interposed therebetween) for supplying the document M one by one is disposed. ing. Further, the paper feed stack unit 2 includes a bottom plate 2a for rotating and holding the supply mechanism 102a side of the stacked bundle of documents M upward from the bottom, and an upper side with respect to the raised bundle of documents M. And a contact roller 2b that pressurizes the contact roller. Note that an out-of-document sensor 4 is provided at the bottom of the paper feed stack unit 2 to detect the absence of the original M due to the rotation angle of the bottom plate 2a.

  A pair of first feeding mechanisms 110a (for example, a pair of opposingly positioned documents M sandwiched between the carry-in section 102 and the first transport section 111 and on the upstream side and the downstream side with the front side reading section 10 interposed therebetween. Feed rollers) are arranged respectively. Further, the second feeding mechanism 120a (for example, an original document) straddles the first direction conversion unit 112, the second conveyance unit 121, and the second direction conversion unit 122 and on the upstream side and the downstream side with the back surface side reading unit 20 interposed therebetween. A pair of feed rollers positioned opposite to each other with M interposed therebetween is disposed. The carry-out unit 103 is provided with a discharge mechanism 103a (for example, a pair of guide rollers positioned opposite to each other with the document M interposed therebetween) for storing the document M after image reading in the discharge stack unit 3. Yes.

  The first transport unit 111 is transported to the first transport unit 111 between the upstream-side first feed mechanism 110a and the front-side reader 10 (that is, upstream of the front-side reader 10) (or A first sensor 110 is disposed for temporarily stopping the conveyance (feed) of the document M when the leading edge of the document M (sent continuously or intermittently) is detected. On the other hand, the second transport unit 121 is transported to the second transport unit 121 between the upstream second feeding mechanism 120a and the back surface reading unit 20 (that is, upstream from the back surface reading unit 20). A second sensor 120 for temporarily stopping the conveyance (feeding) of the document M when the leading edge of the document M is detected (or sent continuously or intermittently). Therefore, for example, when the document M is present in the back side reading unit 20, it is prohibited to carry the subsequent document M into the front side reading unit 10 until the reading of the back side document surface M 2 is completed in the back side reading unit 20. Therefore, the alternate image reading of both document surfaces M1 and M2 can be performed smoothly. It should be noted that it is desirable to use non-contact sensors such as an ultrasonic type, an infrared type, and a capacitance type as these sensors 110 and 120 so as not to disturb the conveyance (feed) of the original M.

  A lower opening 10a and an upper opening 10b are formed in the front side reading unit 10 so as to penetrate the first transport unit 111 in the vertical direction, and the lower opening 10a is formed from the lower side with the first glass plate 11 ( 1st transparent part). On the other hand, the back side reading unit 20 is formed with an opening 20a that opens the second transport unit 121 downward, and the opening 20a is closed from below by the second glass plate 21 (second transparent portion). ing.

  The separation distance along the document conveyance path 1 between the front side reading unit 10 and the back side reading unit 20 is set to be equal to or longer than the length of the document M in the document conveyance path 1 direction. That is, the conveyance distance between the front side reading unit 10 and the back side reading unit 20 is formed to be equal to or longer than the length of the original M in the original conveyance path 1 direction. Of course, the transport distance (separation distance along the document transport path 1) between the sensors 110 and 120 is also set to be longer than the length of the document M in the document transport path 1 direction. Accordingly, the front side document surface M1 is read by the upstream surface side reading unit 10 and the trailing end of the document M conveyed to the downstream side back surface reading unit 20 is the openings 10a and 10b (that is, the light) of the front surface side reading unit 10. Since the connection unit 30) is not blocked, image reading by the back surface side reading unit 20 is not hindered.

  The optical connection unit 30 optically connects the upper opening 10b of the front side reading unit 10 and the opening 20a of the back side reading unit 20 in a straight line. As a result, light can be propagated between the reading units 10 and 20 in a form in which the respective optical axes coincide with each other. The light emitted from the imaging unit 40 (light source 41) has an optical axis orthogonal to the document surfaces M1 and M2 of the document M positioned at the front side reading unit 10 and the back side reading unit 20. Is irradiated. Thus, since the optical axis of the optical connection part 30 is formed in a straight line, the reflecting mirror can be omitted, and the structure can be reduced in size and simplified. Moreover, since the length of the optical connection part 30 becomes relatively short, attenuation accompanying light diffusion or the like can be suppressed.

  The imaging unit 40 is disposed directly facing (facing) the upstream side reading unit 10 on the upstream side, but the front side reading unit 10 with respect to the downstream side reading unit 20 on the downstream side. And indirectly disposed through the optical connection unit 30. Each of the reading units 10 and 20 emits light from a light source 41 such as an LED toward the document surfaces M1 and M2 of the document M that is continuously or intermittently (intermittently) sent along the conveyance direction. An image obtained by forming an image of the reflected light reflected by the surfaces M1 and M2 is converted into an electrical signal and read by an image sensor 42 (solid-state imaging device; image sensor) such as a CCD. In addition, the imaging unit 40 receives light from the image sensor 42 on an imaging surface corresponding to the front side document surface M1 of the document M positioned on the front side reading unit 10 or the back side document surface M2 of the document M positioned on the back side reading unit 20. A focusing mechanism 43 (focus adjustment mechanism) for performing focusing so that the surfaces coincide is provided. Reference numeral 44 denotes a reflecting mirror for directing reflected light to the image sensor 42.

  Therefore, first, when the document M exists in the front side reading unit 10 positioned on the upstream side, the light emitted from the light source 41 of the imaging unit 40 is reflected by the front side document surface M1 of the document M and is captured by the imaging unit 40. Image sensor 42 (see FIG. 8B). Next, when the document M does not exist in the front side reading unit 10 located on the upstream side and the document M exists in the back side reading unit 20 located on the downstream side, the light emitted from the light source 41 of the imaging unit 40 Is reflected by the back side document surface M2 of the document M through the front side reading unit 10 and the optical connection unit 30, and is read by the image sensor 42 of the imaging unit 40 through the optical connection unit 30 and the front side reading unit 10 (return). (See FIG. 8D).

  By the way, in the vicinity (for example, the right side) of the front side reading unit 10 (first glass plate 11) in FIG. 2, a third glass plate 131 for placing a bound document such as a book B as a so-called hand-positioned document. (Third transparent portion) is provided, and a manual placement reading portion 130 (third image reading portion) is provided to read the manual placement original surface M3 held opposite to the upper surface of the third glass plate 131. Yes. The first glass plate 11 and the third glass plate 131 may be integrated.

  This manual placement reading unit 130 is used when reading an image of the manual placement original surface M3 of the book B in a so-called manual reading mode. Specifically, the imaging unit 40 moves (sends) continuously or intermittently along the third glass plate 131 after moving to a position facing the hand-held reading unit 130 (for example, a position below it). ). At this time, light from the light source 41 of the imaging unit 40 is irradiated toward the hand-placed original document surface M3 of the book B, and an image obtained by forming an image of reflected light reflected by the hand-placed original document surface M3 is an image sensor 42. Is converted into an electrical signal and read.

  FIG. 3 shows a block diagram of a control system of such an image reading apparatus 50. As shown in the block diagram of FIG. 3, the reading control unit 90 includes a CPU 92, a RAM 93, a ROM 94, input / output interfaces 91 and 95, and the like in order to control the image reading control of the image reading device 50 (imaging unit 40). These are constituted by a microcomputer connected so that transmission and reception are possible. The CPU 92 executes image reading by the imaging unit 40 based on the image reading control program 94 a read from the ROM 94. The RAM 93 is used as a work area when executing the program.

As shown in FIG. 3, the following signals are input from each unit of the image reading device 50 to the reading control unit 90 via the input interface 91.
Automatic manual selection switch 90a: an operation for selecting and switching between an automatic reading mode for reading images of the front and back document surfaces M1 and M2 of the sheet-like document M and a manual reading mode for reading images of the manually placed document surface M3 of the book B signal;
Double-sided / single-sided selection switch 90b: An operation signal for selecting and inputting whether both sides of the front and back document surfaces M1 and M2 of the sheet-like document M are to be read or only one side is to be read;
Front and back selection switch 90c: an operation signal for selecting and inputting which of the front and back document surfaces M1 and M2 of the sheet-like document M is to be subjected to image reading;
Start switch 90d: an operation signal for instructing start of image reading by the imaging unit 40;
Stop switch 90e: an operation signal for instructing stop (end) of image reading by the imaging unit 40;

First sensor 110: a detection signal indicating that the leading edge of the document M transported (sent) is transported (sent) through the first transport unit 111;
Second sensor 120: a detection signal indicating that the leading edge of the document M being conveyed (sent) is conveyed (sent) by the second conveying unit 121;
Image sensor 42: a detection signal indicating that the leading edge of the document M sent through the first transport unit 111 or the second transport unit 121 has reached the front side reading unit 10 or the back side reading unit 20;
Document out sensor 4: A detection signal (see FIG. 2) that there is no document M in the paper feed stack unit 2.

Similarly, the next signal is output from the reading control unit 90 to each unit of the image reading apparatus 50 via the output interface 95.
A supply actuator 102b: a control output signal for a supply actuator 102b (eg an electric motor) that drives a supply mechanism 102a (eg a separation belt and a separation roller);
First feed actuator 110b: Control output signal for the first feed actuator 110b (eg, stepping motor) that feeds the first feed mechanism 110a (eg, a pair of feed rollers) continuously or intermittently (intermittently). ;
Second feed actuator 120b: Control output signal for the second feed actuator 120b (for example, a stepping motor) that drives the second feed mechanism 120a (for example, a pair of feed rollers) to feed continuously or intermittently (intermittently). ;
Discharge actuator 103b: a control output signal for a discharge actuator 103b (for example, an electric motor) that drives a discharge mechanism 103a (for example, a pair of guide rollers);

Imaging unit driver 40a: control output signal for the imaging unit driver 40a that operates (image reading drive) the imaging unit 40 in the front side reading unit 10, the back side reading unit 20, or the manual placement reading unit 130;
Image pickup unit moving actuator 40b: In the manual reading mode, the image pickup unit 40 is moved to a position opposite to the hand-held reading unit 130, and then continuously or intermittently (intermittently) along the third glass plate 131. A control output signal for the imaging unit moving actuator 40b to be driven (for example, a stepping motor).

  Next, an example of control of the image reading apparatus 50 will be described using the flowcharts shown in FIGS. 4 to 7 and the operation explanatory diagram of FIG. First, in S1 of FIG. 4, it is checked whether or not the automatic reading mode is selected by the automatic manual selection switch 90a. If the automatic reading mode is selected (YES in S1), the states of the first sensor 110 and the second sensor 120 are confirmed in S2, and if both are OFF (YES in S2), the process proceeds to S4. . At this time, if at least one sensor is in an ON state (NO in S2), in S3, the first feed mechanism 110a (first feed actuator 110b), the second feed mechanism 120a (second feed actuator 120b), and the discharge The mechanism 103a (discharge actuator 103b) is simultaneously driven to discharge the undischarged document M existing in the document transport path 1 to the sheet discharge stack unit 3, and the process proceeds to S4.

  Next, in S4, it is checked whether or not the double-sided reading mode is selected by the double-sided / single-sided selection switch 90b. If the duplex scanning mode is selected (YES in S4), the subroutine S5 of the duplex scanning mode is executed (FIG. 5). If the simplex scanning mode is selected (NO in S4), the subroutine S6 of the simplex scanning mode (FIG. 5) is executed. 6) is executed. If the manual reading mode is selected in S1 (NO in S1), the manual reading mode subroutine S7 (FIG. 7) is executed.

  In the double-sided reading mode S5 of FIG. 5, after confirming that the start switch 90d has been operated in S501 (YES in S501), in S502, the supply mechanism 102a (supply actuator 102b) and the first feed mechanism 110a (first The feed actuator 110b) is simultaneously driven to supply (convey) the first document M to the carry-in unit 102 or the first conveyance unit 111. If the first sensor 110 detects the leading edge of the document M and is turned on (YES in S503; see FIG. 8A), in S504, only the first feed mechanism 110a is driven to drive the document. The feeding of M is started and at the same time, the operation of the imaging unit 40 (imaging unit driver 40a) is started. Note that the operation of the imaging unit 40 includes lighting of the light source 41, focusing of the focusing mechanism 43, and scanning of the image sensor 42.

  Thereafter, when the image sensor 42 of the imaging unit 40 detects the leading edge of the original M in the front side reading unit 10 (YES in S505), the front side original by the image sensor 42 of the imaging unit 40 in the front side reading unit 10 in S506. Image reading of the surface M1 is started (see FIG. 8B). When the image sensor 42 of the imaging unit 40 detects the trailing edge of the document M in the front side reading unit 10 (YES in S507), the image reading of the front side document surface M1 in the front side reading unit 10 is finished in S508. To do. In step S509, the second feeding mechanism 120a is driven (or fed), and the document M that has been read is conveyed (or sent) to the second conveying unit 121. If the second sensor 120 detects the leading edge of the document M and is turned on (YES in S510; see FIG. 8C), in S511, only the second feed mechanism 120a is fed and driven. The feeding of M is started and at the same time, the operation of the imaging unit 40 (imaging unit driver 40a) is started. Note that the operation of the imaging unit 40 includes lighting of the light source 41, focusing of the focusing mechanism 43, and scanning of the image sensor 42.

  Thereafter, when the image sensor 42 of the imaging unit 40 detects the leading edge of the document M in the back side reading unit 20 (YES in S512), the back side document by the image sensor 42 of the imaging unit 40 in the back side reading unit 20 in S513. Image reading of the surface M2 is started (see FIG. 8D). When the image sensor 42 of the imaging unit 40 detects the trailing edge of the document M in the back side reading unit 20 (YES in S514), the image reading of the back side document surface M2 in the back side reading unit 20 is terminated in S515. To do. Further, in S516, the second feed mechanism 120a and the discharge mechanism 103a are driven to discharge the original M, which has been read, to the discharge stack unit 3 (see FIG. 8E).

  Then, after confirming that the document cut sensor 4 (see FIG. 2) has not detected the document cut (NO in S517) and that the stop switch 90e has not been operated (NO in S518), the process returns to S502. Carrying in (supplying) the next original M is started. If YES in S517 or YES in S517, the process returns to the main routine (FIG. 4).

  As described above, since the image reading of both the document surfaces M1 and M2 can be performed smoothly even if the document M is not reversed during conveyance, the reversing mechanism can be omitted, and the document M is clogged or damaged during conveyance. Hard to do. By the way, in S505, S507, S512, and S514 of FIG. 5, instead of detecting the leading edge (or trailing edge) of the document M by the image sensor 42, the first sensor 110 (or the second sensor 120) detects the document M. The elapse of a predetermined time from the detection of the leading edge may be used as a determination criterion.

  In the single-sided reading mode S6 of FIG. 6, in S601, it is checked whether image reading of the front side original surface M1 is selected by the front / back surface selection switch 90c. If image reading of the front side document surface M1 is selected (YES in S601), after confirming that the start switch 90d has been operated (YES in S602), in S603, the supply mechanism 102a and the first feeding mechanism 110a are turned on. By driving all at once, the first document M is supplied (conveyed) to the carry-in unit 102 or the first conveyance unit 111. When the first sensor 110 detects the leading edge of the document M and is turned on (YES in S604; see FIG. 8A), in S605, only the first feed mechanism 110a is driven to drive the document. The feeding of M is started, and the operation of the imaging unit 40 is started at the same time. Note that the operation of the imaging unit 40 includes lighting of the light source 41, focusing of the focusing mechanism 43, and scanning of the image sensor 42.

  Thereafter, when the image sensor 42 of the imaging unit 40 detects the leading edge of the original M in the front side reading unit 10 (YES in S606), the front side original by the image sensor 42 of the imaging unit 40 in the front side reading unit 10 in S607. Image reading of the surface M1 is started (see FIG. 8B). When the image sensor 42 of the imaging unit 40 detects the trailing edge of the document M in the front side reading unit 10 (YES in S608), the image reading of the front side document surface M1 in the front side reading unit 10 is finished in S609. To do. In step S610, the second feeding mechanism 120a and the discharge mechanism 103a are driven to discharge the original M, which has been read, to the discharge stack unit 3 (see FIG. 8E).

  Then, after confirming that the document cut sensor 4 (see FIG. 2) has not detected the document cut (NO in S611) and that the stop switch 90e has not been operated (NO in S612), the process returns to S603. Carrying in (supplying) the next original M is started. If YES in S611 or YES in S612, the process returns to the main routine (FIG. 4).

  When image reading of the back side document surface M2 is selected (NO in S601), after confirming that the start switch 90d has been operated (YES in S613), in S614, the supply mechanism 102a, the first The feeding mechanism 110a and the second feeding mechanism 120a are simultaneously driven to supply (convey) the first document M to the second conveying unit 121 or the second direction converting unit 122. If the second sensor 120 detects the leading edge of the document M and is turned on (YES in S615; see FIG. 8C), in S616, only the second feed mechanism 120a is driven to drive the document. The feeding of M is started, and the operation of the imaging unit 40 is started at the same time. Note that the operation of the imaging unit 40 includes lighting of the light source 41, focusing of the focusing mechanism 43, and scanning of the image sensor 42.

  Thereafter, when the image sensor 42 of the imaging unit 40 detects the leading edge of the document M in the back side reading unit 20 (YES in S617), the back side document by the image sensor 42 of the imaging unit 40 in the back side reading unit 20 in S618. Image reading of the surface M2 is started (see FIG. 8D). When the image sensor 42 of the imaging unit 40 detects the trailing edge of the document M in the back side reading unit 20 (YES in S619), the image reading of the back side document surface M2 in the back side reading unit 20 is finished in S620. To do. In step S621, the second feeding mechanism 120a and the discharge mechanism 103a are driven to discharge the original M, which has been read, to the discharge stack unit 3 (see FIG. 8E).

  Then, after confirming that the document cut sensor 4 (see FIG. 2) has not detected the document cut (NO in S622) and that the stop switch 90e is not operated (NO in S623), the process returns to S614. Carrying in (supplying) the next original M is started. If YES in S622 or YES in S623, the process returns to the main routine (FIG. 4).

  As described above, since it is not necessary to provide the document conveyance path 1 and the imaging unit 40 different from the double-sided reading for the single-sided reading, the structure and size of the image reading device 50 can be prevented from being enlarged and complicated, and the single-sided at a high speed. Image reading is possible. By the way, in S606, S608, S617, and S619 in FIG. 6, instead of detecting the leading edge (or trailing edge) of the document M by the image sensor 42, the first sensor 110 (or the second sensor 120) detects the document M. The elapse of a predetermined time from the detection of the leading edge may be used as a criterion.

  In the manual reading mode S7 in FIG. 7, in S701, the imaging unit 40 (imaging unit moving actuator 40b) is driven to move to the position facing the hand-held reading unit 130. Further, after confirming that the start switch 90d has been operated (YES in S702), the imaging unit 40 (imaging unit moving actuator 40b) is sent continuously or intermittently (intermittently) along the third glass plate 131. At the same time, the image pickup unit 40 (image pickup unit driver 40a) is operated, and the image sensor 42 reads an image of the manually placed document surface M3. After confirming that the stop switch 90e is not operated (NO in S704), the process returns to S702 and waits for the next start switch 90d. If YES in S704, the process returns to the main routine (FIG. 4).

  As described above, since the imaging unit 40 can be used for image reading by the manual reading unit 130 in addition to the front side reading unit 10 and the back side reading unit 20, it can be manually operated without increasing the size and complexity of the structure. A reading mode function can be added. By the way, in S704 of FIG. 7, confirmation of the operation of the stop switch 90e and confirmation of the elapse of a predetermined time from the operation of the start switch 90d may be used as the determination criteria under the OR condition.

(Example 2)
FIG. 9 shows another example of the image reading apparatus according to the present invention. In the image reading apparatus 50 shown in FIG. 9, the positional relationship between the paper feed stack unit 2 (original supply unit) and the paper output stack unit 3 (original output unit) is opposite to that in FIG. M is conveyed in the direction opposite to that in FIG. Therefore, the imaging unit 40 is arranged directly facing (facing) the downstream side reading unit 20 (second image reading unit) on the downstream side, but the upstream side reading unit 10 on the upstream side. The first image reading unit is indirectly arranged to face the back side reading unit 20 and the optical connection unit 30. However, after reading the front side document surface M1 (first document surface) of the document M by the front side reading unit 10, the back side document surface M2 (second document surface) of the document M by the back side reading unit 20. The image reading order does not change. In FIG. 9 (Embodiment 2), parts having the same functions as those in FIG. 2 (Embodiment 1) are denoted by the same reference numerals and description thereof is omitted.

(Modification)
FIG. 10 shows a modification of the document conveyance path of FIG. 2 (Example 1). In the document conveyance path 1 of FIG. 10, the first conveyance unit 111, the direction changing unit 112, and the second conveyance unit 121 are formed in a flat U-shape (hairpin curve shape; spelled shape) that is flat as a whole. . Further, the first transport unit 111 and the second transport unit 121 are arranged vertically so as to be substantially parallel to each other, and the front side reading unit 10 (first image reading unit) is disposed on the lower side of each parallel shape. ) And the opening 20a of the back side reading unit 20 (second image reading unit) are formed (arranged). Further, the optical axis of the optical connection unit 30 (light propagation unit) optically connects the front side reading unit 10 and the back side reading unit 20 in a straight line. Then, the light emitted from the light source 41 of the imaging unit 40 has an optical axis that is orthogonal to the document surfaces M1 and M2 of the document M positioned at the front side reading unit 10 and the back side reading unit 20. Irradiated.

  As described above, since the document conveyance path 1 is formed in a flat horizontal U-shape and the conveyance sections 111 and 121 are arranged vertically in parallel, the structure (particularly the vertical structure) is downsized and simplified. Can be achieved. Further, since the optical axis of the optical connecting portion 30 is formed in a straight line, the reflecting mirror can be omitted, and the structure can be reduced in size and simplified. Furthermore, since the length of the optical connection part 30 becomes relatively short, attenuation due to light diffusion or the like can be suppressed. In addition, in the modification shown in FIG. 10, the same code | symbol is attached | subjected to the part which has a function which is common in Example 1 (FIG. 2), and description is abbreviate | omitted.

  In the above embodiment, only the copying machine has been described as the image forming apparatus provided with the image reading apparatus. However, it is of course possible to apply to an image forming apparatus such as a printing machine. Further, a flexible light propagation member such as an optical fiber may be used for the optical connection unit 30 (light propagation unit) or the imaging unit 40.

1 is a schematic explanatory view showing an example of a copying machine as an image forming apparatus according to the present invention. 1 is an explanatory diagram illustrating an example of an image reading apparatus according to the present invention. The block diagram which shows the electric constitution of FIG. The flowchart which shows the action | operation of FIG. The flowchart which shows the operation | movement of double-sided reading mode. The flowchart which shows the action | operation of single-sided reading mode. The flowchart which shows the action | operation of manual reading mode. Explanatory drawing which shows the action | operation of the image reading apparatus based on FIG. FIG. 6 is an explanatory diagram illustrating another example of an image reading apparatus according to the present invention. FIG. 4 is an explanatory diagram showing a modification of the document conveyance path in FIG. 2.

Explanation of symbols

1 Document transport path 10 Front side reading unit (first image reading unit)
20 Back side reading unit (second image reading unit)
30 Optical connection part (light propagation part)
40 Imaging unit 41 LED (light source)
42 Image sensor (charge coupled device (CCD); solid-state image sensor; image sensor)
43 Focusing mechanism (focus adjustment mechanism)
50 Image Reading Device 90 Reading Control Unit 100 Copying Machine (Image Forming Device)
111 1st conveyance part 112 1st direction conversion part (direction conversion part)
121 Second conveying unit 130 Manual reading unit (third image reading unit)
M manuscript (sheet-like manuscript)
M1 Front side document surface (first document surface)
M2 Back side document surface (second document surface)
B Book (manually placed manuscript)
M3 Hand placed document surface P Transfer paper (copy paper; recording material)

Claims (10)

The first transport unit extending in a predetermined direction, the direction changing unit connected to the front end side of the first transport unit and changing the direction, and the first transport unit connected to the front end side of the direction converting unit And a second conveying section extending in the opposite direction, and a sheet-like document to be read by the image is sequentially passed from the document feeding section to the first conveying section, the direction changing section, and the second conveying section toward the document discharging section. A document conveyance path for unilateral conveyance;
A first image reading unit disposed on the first conveyance unit of the document conveyance path for reading a first document surface that is one of the front and back surfaces of the document;
The second document surface of the document conveyance path spaced a predetermined distance downstream from the first image reading unit is arranged to read the second document surface opposite to the first document surface of the document. A second image reading unit provided;
A light propagation unit that optically connects the first and second image reading units so that light propagation between the first and second image reading units is possible in a form in which the respective optical axes coincide with each other;
One of the first and second image reading units is disposed directly opposite to the one image reading unit, and the one image reading unit and the light propagation with respect to the other image reading unit In each image reading unit, light is emitted from the light source toward the document surface of the document that is continuously or intermittently sent along the conveyance direction. A single imaging unit that reads and converts an image obtained by forming an image of the reflected light reflected by the original surface into an electrical signal;
First, in the first image reading unit on the upstream side, light from the light source of the imaging unit is irradiated onto the first document surface, and an image of reflected light reflected by the first document surface is the imaging unit. Read in
Thereafter, in the second image reading unit on the downstream side, light is emitted from the light source of the imaging unit to the second document surface, and an image of reflected light reflected by the second document surface is obtained by the imaging unit. An image reading apparatus that is read. The first transport unit extending in a predetermined direction, the direction changing unit connected to the front end side of the first transport unit and changing the direction, and the first transport unit connected to the front end side of the direction converting unit And a second conveying section extending in the opposite direction, and a sheet-like document to be read by the image is sequentially passed from the document feeding section to the first conveying section, the direction changing section, and the second conveying section toward the document discharging section. A document conveyance path for unilateral conveyance;
A first image reading unit disposed in the first conveying unit of the document conveying path for reading an image displayed on a first document surface which is one of the front and back surfaces of the document;
The image displayed on the second document surface on the opposite side of the first document surface of the document on the second transport unit of the document transport path spaced a predetermined distance downstream from the first image reading unit. A second image reading unit arranged to read
A light propagation unit that optically connects the first and second image reading units in a straight line so that light propagation between the first and second image reading units is possible in a form in which the respective optical axes coincide with each other;
It is disposed directly opposite to the first image reading unit, and indirectly opposed to the second image reading unit via the first image reading unit and the light propagation unit. In each image reading unit, light is emitted from a light source toward the document surface of the document that is continuously or intermittently sent along the conveyance direction, and reflected light reflected by the document surface is reflected. A single imaging unit that reads and converts an image obtained by imaging into an electrical signal;
First, in the first image reading unit on the upstream side, light from the light source of the imaging unit is irradiated onto the first document surface, and an image of reflected light reflected by the first document surface is the imaging unit. Read in
Thereafter, the second image reading unit on the downstream side irradiates light from the light source of the imaging unit to the second document surface through the first image reading unit and the light propagation unit in a straight line, An image reading apparatus, wherein an image of reflected light reflected by a second document surface is read by the imaging unit through the light propagation unit and the first image reading unit in a straight line. When the document is present in the first image reading unit located on the upstream side, the light emitted from the light source is reflected by the first document surface of the document and read by the imaging unit,
When the original does not exist in the first image reading unit located on the upstream side and the original exists in the second image reading unit located on the downstream side, the light emitted from the light source is the first light. Claims that the first image reading unit and the light propagation unit pass in a straight line and are reflected by the second original surface of the original, and pass through the light propagation unit and the first image reading unit in a straight line and read by the imaging unit. Item 3. The image reading apparatus according to Item 2.   4. The separation distance along the document conveyance path between the first and second image reading units is set to be equal to or longer than the length of the document in the document conveyance path direction. 5. The image reading apparatus described in 1. The first transport unit and the second transport unit are arranged vertically so as to be parallel to each other,
The light emitted from the light source of the imaging unit is irradiated so that the optical axis thereof is orthogonal to the document surface of the document located in the first and second image reading units. 5. The image reading apparatus according to any one of 4 above.   The imaging unit includes a solid-state imaging on an imaging surface corresponding to a first document surface of a document located in the first image reading unit or a second document surface of a document located in the second image reading unit. 6. The image reading apparatus according to claim 1, further comprising a focus adjustment mechanism for performing focusing so that light receiving surfaces of image sensors such as elements coincide with each other.   When the original is present in one of the first and second image reading units, the other image reading unit carries another document into the other image reading unit until the reading of a predetermined original surface is completed in the image reading unit. The image reading apparatus according to claim 1, wherein the image reading apparatus is prohibited. There is provided a reading control unit capable of selectively inputting which one of the front and back sides of the original is to be scanned.
Based on the selection input, the reading control unit allows the image reading unit corresponding to the selected document surface of the first and second image reading units to pass the document while reading the document surface. 8. The image reading apparatus according to claim 1, wherein an image reading unit corresponding to an unfinished document surface passes the document without reading the document surface. In the vicinity of the first image reading unit, a document such as a book is placed on the transparent part as a manually placed original, and a first original is read in order to read the original surface opposed to the upper surface of the transparent part. Three image reading units are provided,
The image pickup unit is a document of the manually placed document held on the transparent portion while moving continuously or intermittently along the transparent portion at a position facing the third image reading portion. 4. The image reading according to claim 2, wherein an image obtained by irradiating light from the light source toward the surface and forming an image of reflected light reflected by the document surface is converted into an electric signal and can be read. apparatus. An image forming apparatus comprising the image reading apparatus according to claim 1, wherein an image is formed on a recording material based on a result of image reading of the document by the image reading apparatus. apparatus.

Images