JP3825895B2 - Sheet separating / conveying apparatus and image forming apparatus having the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sheet separating and conveying apparatus that automatically separates and conveys a plurality of sheets and an image forming apparatus including the same.
[0002]
[Prior art]
For example, when a document as a plurality of sheets is set on a document table and transmitted to a document reading unit of a facsimile machine as an image forming apparatus, the sheets are automatically separated and conveyed one by one. An automatic document separating and conveying device is provided.
[0003]
Many automatic document separating and conveying apparatuses have a mechanism for bringing a separation piece into contact with a separation roller to separate the document and pressing the separation piece with an elastic body such as a spring. This apparatus controls a drive source by a signal from a sensor that detects the presence or absence of a document, rotates a separation roller in a document transport direction, and generates a frictional force between documents, a frictional force between a document and a separation piece, This is a device that separates and conveys only one document in contact with the separation roller among a plurality of documents using the difference in frictional force between the separation rollers.
[0004]
In such a document conveyance system, conventionally, a rib-like protrusion is provided on the sheet guide member in order to prevent the document from being charged with static electricity due to friction and sticking to the sheet guide member to cause a conveyance failure. Thus, means for reducing the contact area with the document have been used.
[0005]
In addition to the functions of facsimile transmission and reception, in the case of a facsimile (multifunction facsimile) having a function of performing color copying or a function of a scanner connected to a computer and taking a color image into the computer, the facsimile transmission A paper different from the paper used in is used as a manuscript.
[0006]
For example, newspaper clippings, color photographs, magazine color pages, business cards, and the like are possible. Newspapers and magazine clippings are thin and weak paper types, and in many cases there is also printing on the back. When transporting these, it is essential that the original document is not damaged and the back surface is not soiled as well as the separation performance.
[0007]
A rubber material having a high friction coefficient is used for the separation piece of the sheet conveying portion of the conventional facsimile apparatus. Even if the pressing force of the separating piece is weakened, the original may be scratched or damaged due to the high friction coefficient of the separating piece. By rubbing the rubber material used for the separation piece and the original, the rubber mark (rubber residue) of the separation piece adheres to the back surface of the original.
[0008]
Further, when a thick and hard sheet such as a business card is used as a document, it is difficult to convey the document only by reducing the pressing force of the separation piece. From the above, when transporting cardboard (business cards, etc.), for example, in order to transport originals such as photographs and newspapers without leaving rubber marks on the back side, the separation piece is completely removed from the separation roller. A mechanism to release is required. And the mechanism which releases a separation piece is proposed.
[0009]
[Problems to be solved by the invention]
However, even in an automatic document separating and conveying apparatus provided with a release mechanism as in the above-described conventional example, in a special document such as a glossy photograph, the document may be damaged due to friction with the sheet guide member. In order to prevent this, it is effective to reduce the friction of the original by arranging a large number of rollers for guiding the guide on the surface of the sheet guide member, but the structure of the apparatus becomes complicated and the cost increases. There was a fault that would be.
[0010]
SUMMARY OF THE INVENTION An object of the present invention is to provide a sheet separating / conveying apparatus capable of separating and conveying a thick sheet without damaging its original surface.
[0011]
[Means for Solving the Problems]
The invention according to claim 1 is a sheet insertion port for inserting several sheets;
Separating and conveying means for separating and conveying the sheet inserted from the sheet insertion port;
Separating the sheet in pressure contact with the separating and conveying means, the separating means disposed in the center of the sheet conveying direction and the crossing direction;
Urging means for pressing the separating means against the separating and conveying means;
Upper and lower conveyance guide means for guiding the separation and conveyance means and the sheet separated and conveyed by the separation means;
Reading means for reading a document image of the separated and conveyed sheet;
Sheet discharge means for discharging the sheet read by the reading means;
With
The guide surface of the conveyance guide means on the reading means side is a smooth surface having no protrusions or ribs.
[0012]
The invention according to claim 2, wherein the lower conveyance guide means is characterized in that the smooth surface without protrusions or ribs is limited to a range in which a thick sheet of a small size or less is conveyed.
[0013]
The invention according to claim 3 is characterized in that the lower conveyance guide means is capable of guiding a normal size sheet outside the smooth surface and has a projection or a rib parallel to the sheet conveyance direction.
[0014]
The invention according to claim 4 is characterized in that the sheet conveyed on the smooth surface is a photograph.
[0015]
The invention according to claim 5 is characterized in that when the sheet is conveyed to the smooth surface, the urging operation of the urging means is released.
[0016]
[Action]
Based on the above configuration, the plurality of sheets inserted into the insertion port are separated one by one by the cooperation of the separating and conveying means and the separating means pressed by the urging means, and conveyed by the conveying guide means, and the reading means After the image information is read in this way, it is discharged by the sheet discharge means.
[0017]
When the sheet (for example, a document) is a special sheet such as a thick small-size sheet, the sheet slides on the smooth surface of the conveyance guide, and is read out after image information is read by the reading unit. This prevents damage to the image on the sheet due to rubbing against the rib protrusions on the conveyance guide, and image reading failure due to this.
[0018]
In addition, the area formed by the smooth surface of the conveyance guide is limited to the size of the sheet that is particularly susceptible to image damage, and other parts of the conveyance guide are formed by rib-shaped protrusions, for other sheets, Prevention of transport failure due to static electricity placed during transport is prevented.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a sheet separating and conveying apparatus according to the present invention and an image forming apparatus including the same will be described with reference to the drawings.
[0020]
FIG. 1 is an external perspective view of a case where a reading and recording apparatus (facsimile apparatus) is used as an example of an image forming apparatus.
[0021]
In FIG. 1, a color reading facsimile apparatus 1000 which is a reading and recording apparatus includes a color scanner apparatus 800 which is a document conveying type color reading apparatus and a recording apparatus which will be described later, inside a housing constituting front, rear, left and right side walls as shown. A serial recording type recording device, a color control board, and a power source are incorporated. Each of these components is individually configured so that they can be easily replaced and attached.
[0022]
The casing is composed of a lower cover 100 that is a lower first casing, an upper cover 200 that is an upper second casing, and a rear cover that is a third casing, which will be described later, for guiding a recording sheet and covering a power source. Basically composed.
[0023]
Further, the upper cover 200 is provided with a slider 3 that can be adjusted in width to guide the width direction of the document, and that moves only about one side to move around the central portion. The document table 2 is rotatably supported with respect to the upper cover 200 as described later, thereby enabling access to the recording head.
[0024]
A detachable document stacking tray 4 is provided behind the document table 2. For example, when an A4 size document is conveyed forward toward the color scanner unit 800, the trailing edge does not hang down. I am doing so.
[0025]
A document (sheet) transported forward with the document surface at the bottom is transported from below the color scanner unit 800 to the front of the apparatus 1000 and placed on the document discharge tray 6. The document discharge tray 6 is movable in the front-rear direction of the apparatus 1000 as indicated by an arrow.
[0026]
On the other hand, the recording sheet conveyed to the recording apparatus is described later after the width direction is regulated by the movement of the width adjusting plate 9 provided on the recording sheet base 401 disposed on the back side of the apparatus 1000. After the serial recording in the printer unit, the sheet is discharged to the recording sheet base 8 below the color scanner unit 800.
[0027]
When the recording sheet is conveyed so that its longitudinal direction is the longitudinal direction of the apparatus, the rear recording sheet support 5 and the front recording sheet support bar 7 are provided to prevent the sheet from sagging. Is provided. The support base 5 is built in the recording sheet base 401, and is configured to be in the position shown in the drawing by being pulled out appropriately. On the other hand, the recording sheet support bar 7 on the front side is provided so that it can be pulled out in the front-rear direction, similar to the document discharge tray 6 described above.
[0028]
Further, the upper cover 200 has a shape surrounding the color scanner unit 800 as shown in the figure, and is removed from the lower cover 100 along the edge 202 of the upper cover 200, whereby the color scanner unit 800 is removed. It can be left on the lower cover 100.
[0029]
To the color scanner unit 800, a scanner main body unit and a panel unit are coupled so as to open and close about a hinge (not shown). In addition, a liquid crystal display unit 811, a dial key 810, and other operation units are disposed on the panel unit as illustrated.
[0030]
FIG. 2 is a vertical side view of the apparatus 1000, and the upper cover 200 is omitted.
[0031]
In this figure, the same reference numerals are given to the components that have already been described, and description thereof is omitted. Inside the lower cover 100 in which a base portion serving as a bottom surface, a side wall serving as an outer appearance surface, and an opening surface surrounded by the side walls are integrally formed, a color scanner unit 800 serving as a document conveyance type reading device that reads a document while conveying the document, and a recording Printer 400, which is a serial recording paper type recording apparatus that performs serial recording while conveying a sheet, a color control board and a power supply 600 that are connected to these printers to perform predetermined control, and absorbs ink that is unnecessary for initial ejection. The ink absorber 13, the rear cover 15, the recording sheet base 8, and the speaker 16 all can be fixed to the lower cover 100 without using any tools.
[0032]
Next, the configuration of each part in FIG. 2 will be described in detail.
[0033]
First, the color scanner unit 800 will be described with reference to FIGS.
[0034]
The color scanner unit 800 irradiates the original G with light, converts the reflected light into an electric signal, and transmits the signal to another machine or transmits it to the printer unit 400 according to the operation mode. is there. The document G is stacked on the document table 2.
[0035]
In the color scanner main body 800, reference numeral 831 denotes a frame of the color scanner 800, which is a scanner base that guides the lower side of the original G. The scanner base 831 is fixed to the lower cover 100. The scanner base 831 also includes a separation roller 832 for feeding out the original G, a feed roller 833 for conveying the original G, a discharge roller 834 for discharging the original G onto the original discharge tray 6, and reading image information of the original G. A color contact sensor (reading means) 835 and the like are provided.
[0036]
Further, the panel portion is rotatably attached to the scanner base 831 by a fulcrum (not shown), and is separated from the upper document guide 836 for guiding the upper side of the document and the separation roller (separation transport means) 832 and separated to be separated (separated) Means) 837, a feeding roller 833, a feeding roller 838 in pressure contact therewith, a paper discharge roller 839 in pressure contact with the paper discharge roller 834, and a color contact sensor 835, which are pressed against each other and become a reading white reference as a reading white reference 840, a release lever 841 for releasing the pressing of the separation piece 837 and the like are provided for conveying a thick original.
[0037]
Reference numeral 842 denotes an operation panel, which is a part of the exterior and is attached to the upper document guide. The operation panel 842 includes operation keys 843, a display unit 844 such as an LCD, a panel substrate 845 on which they are mounted, and the like. Is provided.
[0038]
Here, the document conveying and reading operations of the color scanner unit 800 are performed by a motor or a sensor driving circuit (not shown), and the control of these and the display control of the panel unit 801 are controlled by a color control board. Is done.
[0039]
Next, the printer 400 will be described.
[0040]
An intermediate plate 402 is rotatably supported on a recording sheet base 401 of the printer 400 by a fulcrum (not shown) and is pressed by a spring (not shown). The recording sheet base 401 is fixed to the printer main body 400 with screws or the like.
[0041]
The recording sheet S is stacked on the middle plate, and the back surface thereof is supported by a paper feed tray 405 provided on the recording sheet base 401 so as to be extendable. The position in the width direction is a width movably provided on the middle plate. It is regulated by the adjustment plate 9. Further, the paper feed roller feeds the recording sheets one by one and sends the recording sheet S to the printer unit 400.
[0042]
The printer main body 400 is a so-called ink jet recording method, but 411 is a printer chassis that is a frame of the printer main body 400 and is fixed to the lower cover 100. Reference numeral 412 denotes a paper feed roller, which feeds the recording paper S sent from the paper feed unit to a further downstream print unit when pressed by a pinch roller disposed oppositely. Reference numeral 414 denotes a platen that supports the back side of the recording paper in the printing unit. On the surface of the recording paper, recording is performed by an ink head (image forming unit) 417 attached to a reciprocating carriage 416 supported by a guide shaft 415. An image is formed.
[0043]
Thereafter, the recording paper S is discharged from the printer unit 400 by the recording paper discharge roller pair 418 and is transported and stacked on the recording sheet table 8 provided on the lower cover 100.
[0044]
Here, recording paper conveyance and recording operations of the printer unit 400 are performed by a motor, a sensor, a head driving circuit, and the like (not shown), and these controls are controlled by the control board unit. The substrate 421 is a recording relay substrate that relays signals from these motors, sensors, head drive circuits, etc., and transfers them to the control substrate section. In addition, the absorber 13 that absorbs the waste ink that is generated when the printer unit 400 performs an operation such as prevention of ink clogging is attached to the lower cover 100.
[0045]
Next, the flow of the original sheet G will be described.
[0046]
FIG. 3 is an enlarged cross-sectional view of the color scanner device 800. The document transport path is as indicated by the arrow F. In FIG. 2, reference numeral 4 denotes a document stacking tray, and the document G is stacked with the image surface facing downward. The original G loaded on the original stacking tray 4 is positioned by the slider 3 that can move in the width direction.
[0047]
Reference numeral 906 denotes a preliminary conveyance arm, which is located at a portion facing the separation roller 832. This preliminary conveyance arm is pressed against the separation roller 832 by a preliminary conveyance spring 904 described later. The set original G is rolled and preliminarily conveyed by the cooperative action of the auxiliary conveyance arm 906 and the separation roller 832.
[0048]
Reference numeral 837 denotes a separation piece. The separation roller 832 is pressed from above by an ADF spring (biasing means) 903, and the preliminarily conveyed document G is moved downward by the cooperative action of the separation piece 837 and the separation roller 832. Are separated and conveyed one by one. Further, the separation roller 832 also serves to convey the document G to the feeding roller 833.
[0049]
The original G conveyed by the separation roller 832 is conveyed by the feeding roller 833 to the reading position of the contact color sensor 835. The color contact sensor 835 reads an image of the document G conveyed by the feeding roller 833. A white reading sheet 840 made of white sheet metal is urged from above by a white background spring 907 along the reading line of the color contact sensor 835, and the image of the separated document G is read from the reading line of the color contact sensor 835. It is closely attached to.
[0050]
The original G conveyed and read by the color contact sensor 835 is discharged by a paper discharge roller 834. Reference numeral 6 denotes a document discharge tray on which the discharged document G is stacked, and is configured to be detachable from the main body.
[0051]
Next, the sheet separating and conveying unit D will be described.
[0052]
FIG. 4 shows an enlarged perspective view of a sheet separating and conveying unit which is a D part of FIG. In the present embodiment, the separation piece release mechanism 920 that releases and holds the separation piece 837 will be described in detail.
[0053]
In FIG. 3, 902 is an upper document guide, and 901 is a lower document guide. The document sheet is set in a document insertion slot M formed between the upper document guide 836 and the lower document guide 901.
[0054]
3 and 4, reference numeral 837 denotes a separation piece made of a friction member such as a rubber piece, and is attached on the ADF holder 905. Reference numeral 906 denotes a preliminary transport arm, which is made of a plastic member having a relatively small friction coefficient. A protruding shaft 905 a extends from the ADF holder 905. The preliminary transport arm 906 is provided with a concave portion 906a, and a projection shaft 905a of the ADF holder 905 is attached to a recessed portion of the concave portion 906a.
[0055]
The preliminary transport arm 906 can rotate around the concave portion 906a. Reference numeral 904 denotes a preliminary conveyance pressing spring, which is a tension coil spring. Of the two ends of the preliminary conveyance pressing spring 904, one side is attached to the preliminary conveyance arm and the other is attached to the protrusion of the ADF holder.
[0056]
A concave portion (not shown) is provided on the upper document guide 836, and a protrusion shaft 905a of the holder is attached to the concave portion of the concave portion. The ADF holder 905 can rotate around the 905a axis. The ADF holder 905 is located at a position facing the separation roller 832, and is arranged so that the preliminary conveyance arm 906 and the separation piece 837 come into contact with the separation roller 832.
[0057]
One end of the ADF spring 903 is engaged with the receiving surface 905 b of the holder 905, and the other end is engaged with the operation panel 842. The ADF spring 903 is a compression coil spring. The separation piece 837 on the holder 905 is pressed against the separation roller 832 by the ADF spring 903 elastic force.
[0058]
The preliminary conveyance pressing arm 906 is pressed against the separation roller 823 by the action of the ADF spring 903 and the preliminary conveyance spring 904 in which the pressing force of the ADF spring 905 is set larger than the tensile force of the preliminary conveyance spring 904.
[0059]
Reference numeral 841 denotes a separation piece release lever. The separation piece release lever 841 is a member for providing a gap between the separation piece 837 and the separation roller 832 described above and maintaining the state. In FIG. 4, an inclined portion 841a and a flat portion 841b are provided at the tip of the separation piece release lever 841.
[0060]
FIG. 5A shows a state where the ADF holder 905 and the separation piece release lever 841 are assembled on the upper document guide 836. The separation piece release lever 841 is attached to a shaft 902a on the upper document guide 836, and is rotatable about the shaft 902a. By operating the separation piece release lever 841 in the release operation direction, the inclined portion 841a at the tip of the separation piece release lever 841 pushes up the protrusion 905c of the ADF holder 905.
[0061]
Further, as shown in FIG. 5A, the separation piece release lever 841 has a DS sensor 501 that detects the presence / absence of a document with respect to the separation piece 837 located at the center, a DS actuator 502, and the rear of the document. The DES sensor 504 for detecting the end and the DES actuator 505 are arranged on the opposite side of the arrangement side. Thereby, even if the separation piece release lever 841 is operated, it does not approach the sensor, the sensor actuator, and the cables 503 and 506 from the sensor.
[0062]
The operation of the separation piece release mechanism 920 will be described with reference to FIGS.
[0063]
In FIG. 5A, when the separation piece release lever 841 is operated in the direction of arrow I, the inclined portion 841a at the tip of the separation piece release lever 841 comes into contact with the ADF holder protrusion 905c. Further, when the separation piece release lever 841 is operated in the direction of the arrow I as it is, the protrusion 905c of the ADF holder 905 rotates upward about the protrusion shaft 905a due to the inclination of the tip of the separation piece release lever 841. Further, when the protrusion 905c comes to the flat portion 841b at the tip of the separation piece release lever, the protrusion 905c of the ADF holder 905 is held in a lifted state. This is the state of FIG.
[0064]
FIG. 6 is a cross-sectional view when the separation piece release lever 841 is operated to lift and hold the tip of the ADF holder. H is a gap formed between the separation piece 837 and the separation roller 832 by operating the separation piece release lever in the direction of the arrow in FIG.
[0065]
Since the force with which the ADF spring 903 presses the ADF holder 905 is strong, the preliminary transport arm 906 is pressed against the separation roller 832 by the elastic force of the preliminary transport spring 904. Therefore, even when the separation piece release lever 841 is operated, the preliminary conveyance arm 906 is kept pressed by the separation roller 832. The pressing position of the preliminary transport arm 906 is the same as when the separation piece 837 is not separated.
[0066]
Since no frictional force is applied between the separation piece 837 and the original G, the separation function of a plurality of sheets is lowered, and a thick paper original (for example, a photograph) G can be fed one sheet.
[0067]
In addition, the rubber mark of the separation piece 837 does not adhere to the back side of the document, and the sheet is not damaged by friction with the separation piece 837.
[0068]
As described above, the separation piece 837 can be released from the separation roller 832 by operating the separation piece release lever 841 without the user having to disassemble the device.
[0069]
Next, the state of the separation piece release lever 841 on the appearance of the apparatus when the separation piece 837 is released will be described.
[0070]
FIG. 7 shows a diagram in which the operation panel 842 and the separation piece release lever 841 are arranged. FIG. 7A shows a normal state (when the pressing force is set strongly), and FIG. 7B shows a state when the separation piece 837 is released from the separation roller 832.
[0071]
In FIG. 7A, the operation portion 841a (FIG. 5) of the separation piece release lever 841 is very small and is slightly visible to the user. By operating the operation portion 841a of the separation piece release lever 841 from this state in the direction of arrow I, the separation piece 837 is released from the separation roller 832 and at the same time, the lever operation portion protrudes from the central portion of the document insertion opening M ( FIG. 7B).
[0072]
If the separation piece 837 is released, the operation portion 841a of the separation piece release lever 841 protrudes almost at the center of the document insertion slot M, so that the user inserts the document bundle into the sheet insertion slot M. It is easy to recognize that the separation piece 837 is released from its appearance (the state in which the lever operation portion protrudes) when it is set in the box. This eliminates the mistake of setting a bundle of documents at a time with the separating piece 837 released.
[0073]
As described above, the separation piece 837 can be released from the separation roller 832 by operating the lever from the outside without the user having to disassemble the device. However, the present pressing state of the separation piece 837 can be known from the appearance.
[0074]
In the separation piece release lever 841 in FIG. 7, the portion of the operation portion 841 of the separation piece release lever 841 operated by the user is shown as a thin member. Increasing the width of the operation unit has an advantage of easily recognizing the state of the separation pressure.
[0075]
Further, as an example, the width of the operation portion 841a is widened as shown in FIG. 8, and the operation portion is formed in a “<” shape as shown by 84lc, so that the state when the separation piece 837 is released is changed. It becomes easy to recognize.
[0076]
FIGS. 9A and 9B are external views of the apparatus when the separation piece release lever 841 having the above-described configuration is attached. FIG. 9A shows a normal state, and FIG. 9B shows a state when the separation piece 837 is released from the separation roller.
[0077]
In this way, when the user tries to set a bundle of documents at a time with the separation piece 837 released, the user should be longer in the main scanning direction than when the operation unit is a thin member. It is easy for the user to recognize. For this reason, it is possible to prevent double feeding due to the insertion of a bundle of originals more than when the original is a thin member.
[0078]
If the color of the separation piece release lever 841 is different from that of the operation panel 842 and the original G, the user can easily recognize the state of the separation piece 837. Many colors on the back of the document are close to white. Further, when the operation panel portion of the facsimile apparatus 1000 has a color close to white, for example, if the operation lever is in a color such as red, green, or dark gray, the separation piece is released when the separation piece 837 is released. The lever 841 stands out from the original G and the operation panel 842, and the user can easily recognize the state of the separation piece 837.
[0079]
In addition, when the separation piece 837 is released, the user can easily recognize the message 841d by writing the message 841d on the operation unit 841c protruding outside the operation panel 842.
[0080]
FIG. 10 shows a state of the separation piece release lever 841 when the separation piece 837 is released as an example. By displaying a sentence such as “Sheet cannot be separated” or a word such as “A Thick Sheet” or “ADF OFF” on the lever, the current state of the separation unit can be expressed.
[0081]
According to the above embodiment, since the separation piece 837 can be released from the separation roller 832 by operating the separation piece release lever 841, the separation piece 837 is easily released and the separation piece 837 is released. In this case, it is possible to convey a card with a print on a cardboard or a back surface such as a photograph.
[0082]
When the separation piece is released, the operation portion 841a of the separation piece release lever 841 is outside the apparatus and protrudes substantially to the center on the sheet insertion port M side. The state of 837 can be easily recognized from the position or appearance of the separation piece release lever 841.
[0083]
Next, the lower document guide 901 portion of the sheet separating and conveying apparatus according to the present invention will be described.
[0084]
FIG. 11 is a view showing a document guide section below the document transport section. FIG. 11A is a view showing a conventional paper guide portion, and FIG. 11B is a view showing a lower guide portion of the present embodiment.
[0085]
In FIG. 11A, in the lower document guide 901 of the conventional sheet separating and conveying apparatus, the lower document guide 901 is provided with a plurality of ribs (or protrusions) so that the friction between the conveyed sheet and the lower document guide 901 is achieved. This prevents the occurrence of static electricity on the sheet due to the above, and poor conveyance due to this.
[0086]
In the present embodiment, as shown in FIG. 11B, a rib 950 is not provided at the center of the lower document guide 901 in the main scanning direction, and a flat surface 921 is formed.
In the present embodiment, the area of the smooth flat surface 921 is set to be slightly wider than the size of a general-purpose photograph (smaller than the normal sheet size), and particularly corresponds to a scratched photographic document. I have to. At the same time, ribs 950 are left on the lower document guide 901 at positions corresponding to both ends of a normal A4 size paper document or the like, thereby preventing friction between the sheet and the lower document guide 901 and static electricity caused thereby. This reduces the effect of sheet conveyance failure due to static electricity.
[0087]
As described above, according to the present embodiment, a document such as a photograph whose image surface is easily damaged can be transported without being damaged by the rib member of the document transport path, and the reliability of the apparatus can be improved. it can.
[0088]
【The invention's effect】
As described above, according to the present invention, the conveyance guide means for guiding the sheet is configured with a smooth surface without ribs or protrusions, so that a thick sheet such as a photograph is damaged on the surface (image surface). It can be transported without doing.
[0089]
Also, the range of the smooth surface of the conveyance guide means is limited to the conveyance range of special sheets of small size such as photographs, and ribs that can guide sheets of normal size are provided in other ranges. Further, it is possible to prevent sliding between the sheet and the conveyance guide means and the occurrence of static electricity and conveyance failure.
[Brief description of the drawings]
FIG. 1 is a perspective view of an image forming apparatus provided with a sheet separating and conveying apparatus according to the present invention.
FIG. 2 is a longitudinal side view of the image forming apparatus.
FIG. 3 is an enlarged longitudinal front view of the sheet separating and conveying apparatus.
FIG. 4 is a perspective view of a separation piece releasing mechanism.
FIG. 5 is a plan view of the separation piece release mechanism, in which FIG. 5A is a normal view, and FIG. 5B is a view showing the release of the separation piece.
FIG. 6 is an enlarged vertical side view of the sheet conveying unit when the separation piece is released.
FIG. 7 is also a plan view of an operation panel provided with a separation piece release lever, in which FIG. 7A shows a state in which the separation piece release lever is in a normal state, and FIG. 7B shows a state in a release state. .
FIG. 8 is a plan view showing a modified example of the operating portion of the separation piece release lever.
Similarly, FIG. 9 is a plan view of an operation panel provided with the separation piece release lever of FIG. 8, wherein (a) shows a state in which the separation piece release lever is in a normal state, and (b) shows a state in the release state. FIG.
FIG. 10 is a plan view of a separation piece release lever and an operation panel that are similarly provided with a display unit in the operation unit.
11A and 11B are a lower document guide for guiding a sheet, in which FIG. 11A is a conventional lower document guide, and FIG. 11B is a perspective view of a lower document guide according to an embodiment of the present invention.
[Explanation of symbols]
G Original (sheet)
S Recording sheet
M Document insertion slot (sheet insertion slot)
832 Separation roller (separation conveyance means)
834 Paper discharge roller (sheet discharge means)
835 color contact sensor (reading means)
836 Upper document guide (conveyance guide means)
837 Separation piece (separation means)
901 Lower document guide (conveyance guide means)
904 Preliminary transfer spring (biasing means)
921 Smooth surface
950 ribs

Claims (6)

A sheet insertion slot for inserting a plurality of sheets,
Separating and conveying means for separating and conveying the sheet inserted from the sheet insertion port;
Separating the sheet in pressure contact with the separating and conveying means, the separating means disposed in the center of the sheet conveying direction and the crossing direction;
Urging means for pressing the separating means against the separating and conveying means;
Upper and lower conveyance guide means for guiding the separation and conveyance means and the sheet separated and conveyed by the separation means;
Reading means for reading a document image of the separated and conveyed sheet;
Sheet discharge means for discharging the sheet read by the reading means;
With
The sheet separating and conveying apparatus, wherein the guide surface of the conveying guide means on the reading means side is a smooth surface without protrusions or ribs. 2. The sheet separating and conveying apparatus according to claim 1, wherein in the lower conveying guide unit, the smooth surface without protrusions or ribs is limited to a range in which a thick and small-sized sheet is conveyed. The sheet separating and conveying apparatus according to claim 2, wherein the lower conveying guide unit is capable of guiding a normal size sheet outside the smooth surface, and has a protrusion or a rib parallel to the sheet conveying direction. The sheet separating and conveying apparatus according to claim 1, wherein the sheet conveyed on the smooth surface is a photograph. 5. The sheet separating and conveying apparatus according to claim 1, wherein when the sheet is conveyed to the smooth surface, the urging operation of the urging unit is released. 6. A sheet separating and conveying apparatus according to claim 1, and an image forming section capable of forming an image based on image information of the sheet conveyed by the sheet separating and conveying apparatus. Image forming apparatus.

Images