JPH05297661A - Copying machine - Google Patents

Abstract

PURPOSE:To shorten copying time and to improve efficiency in copying by speedily aligning sheets in an intermediate tray. CONSTITUTION:The copying machine includes the intermediate tray T which receives sheets X and Y; a side-end regulating plate 4 provided on the intermediate tray T to align the sheets X and Y, received on the intermediate tray T, along their width; and a rear-end regulating plate 5 which is provided on the intermediate tray T to align the received sheets along their length and freely moves from a first position where the received sheets are aligned along the length to a second position where other sheets to be received next are aligned along their length.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copying machine having an intermediate tray.

[0002]

2. Description of the Related Art In a conventional aligning device provided on a sheet of an intermediate tray, at the timing of feeding the sheet,
First, the aligning plate of the paper was moved, and at the time of completion of setting, the feeding of the paper from the registration roller to the intermediate tray was started. However, in this case, the movement of the aligning plate has been required to run out of paper in the intermediate unit for alignment.

[0003]

Therefore, in the conventional aligning apparatus, when different sheets are fed, it takes a considerably long time when the size changes from the minimum size to the maximum size, and the copy processing time is delayed, and the processing is delayed. It was reducing efficiency.

SUMMARY OF THE INVENTION It is an object of the present invention to quickly perform a sheet aligning operation in an intermediate tray to shorten the copy processing time and improve the copy processing efficiency.

[0005]

SUMMARY OF THE INVENTION According to the present invention, an intermediate tray for receiving a sheet, a side end regulating plate provided on the intermediate tray for aligning the sheet received in the intermediate tray in terms of width, and the received sheet are provided. Align the other sheets in length according to the length of another sheet to be received next from the first position provided in the intermediate tray to align the length of the received sheet in order to align in length. And a rear end regulating plate movable to a second position.

[0006]

The side edge regulating plate aligns the sheet received on the intermediate tray with respect to the width, and the rear edge regulating plate aligns the received sheet with respect to the length at the first position. The tray is movable from the first position to the second position, which aligns the other sheets in length according to the other sheets to be received next, so that the tray cooperates with the side end regulating plate to feed from the intermediate tray. It is possible to prevent skewed feeding when paper and reduce the copy processing time. Further, the copy processing efficiency can be improved.

[0007]

Embodiments of the present invention will be described with reference to the drawings.

Here, a digital copying machine will be described as an example of the copying machine of the present invention.

FIG. 3 is a sectional view showing the overall construction of the digital copying machine.

As shown in FIG. 3, the copying machine 30 includes a scanner unit 31, a laser printer unit 32, and a multi-stage paper feeding unit 3.
3 and a sorter 34 are provided.

The scanner unit 31 includes a document placing table 35 made of transparent glass and a double-sided automatic document feeder (RDF) 36.
And a reading unit, that is, a scanner unit 40
It consists of

The multi-stage paper feeding unit 33 includes the first cassette 5
It has the 1st, 2nd cassette 52, the 3rd cassette 53, and the 4th cassette 55 which can be added by selection.

In the multi-stage sheet feeding unit 33, the sheets are fed one by one out of the sheets stored in the cassettes of the respective stages, and are conveyed toward the laser printer unit 32.

The RDF 36 sets a plurality of originals at one time, automatically feeds the originals one by one to the scanner unit 40, and scans one side or both sides of the original according to the operator's selection. It is configured to be read by the unit 40.

The scanner unit 40 includes a lamp reflector assembly 41 for exposing a document, a plurality of reflection mirrors 43 for guiding a reflected light image from the document to a photoelectric conversion element (CCD) 42, and a reflected light image from the document. A lens 44 for forming an image on the CCD 42 is included.

When scanning a document placed on the document table 35, the scanner section 31 is configured to read the document image while the scanner unit 40 moves along the lower surface of the document table 35. When the RDF 36 is used, the original image is read while the original is conveyed while the scanner unit 40 is stopped at a predetermined position below the RDF 36.

The image data obtained by reading the original image with the scanner unit 40 is sent to an image processing section (not shown), which will be described later, and after being subjected to various kinds of processing,
The image data is temporarily stored in the memory of the image processing unit, and the image data in the memory is given to the laser printer unit 32 in response to an output instruction to form an image on a sheet.

The laser printer unit 32 includes a manual document tray 45, a laser writing unit 46, and an electrophotographic process unit 47 for forming an image.

The laser writing unit 46 is a semiconductor laser which emits laser light corresponding to the image data from the above-mentioned memory, and a polygon mirror which deflects the laser light at a constant angular velocity.
The laser light deflected at a constant angular velocity is provided with an f-θ lens for correcting the laser light so that the laser light is deflected at a constant velocity on the photosensitive drum 48 of the electrophotographic process section 47.

In the electrophotographic process section 47, a charging device, a developing device, a transfer device, a peeling device, a cleaning device, a static eliminator and a fixing device 49 are arranged around the photosensitive drum 48 according to a well-known mode. ing.

A conveying path 50 is provided downstream of the fixing device 49 in the conveying direction of the sheet on which the image is to be formed. The conveying path 50 is connected to the sorter 34 and a conveying path 57 and a multi-stage sheet feeding unit. It is branched to the conveyance path 58 leading to 33.

The multi-stage paper feeding unit 33 is a double-sided unit 11,
The common conveyance path 56 is included, and the common conveyance path 56 is configured to carry out the sheets from the first cassette 51, the second cassette 52, and the third cassette 53 toward the electrophotographic process section 47.

The common conveying path 56 is the electrophotographic process section 47.
On the way to the transport path, it joins the transport path 59 from the fourth cassette 55 and leads to the transport path 60.

The conveying path 60 is a confluence point 62 of the double-sided / composite conveying path 50b and the conveying path 61 from the manual document tray 45.
And the photoconductor drum 48 of the electrophotographic process unit 47
And a transfer device, and a confluence point 62 of these three conveying paths is provided at a position close to the image forming position.

Therefore, in the laser writing unit 46 and the electrophotographic process section 47, the image data read from the above-mentioned memory is stored in the laser writing unit 46.
The toner image is formed as an electrostatic latent image on the surface of the photoconductor drum 48 by scanning the laser beam by the toner, and the toner image visualized by the toner is the toner image of the sheet conveyed from the multi-stage paper feeding unit 33. It is electrostatically transferred and fixed on the surface. The sheet on which the image is thus formed is sent from the fixing device 49 to the sorter 34 via the carrying paths 50 and 57, or is carried to the reverse carrying path 50a via the carrying paths 50 and 58.

Next, the structure and function of the image processing unit included in the copying machine 30 will be described.

FIG. 4 is a block diagram of the image processing unit included in the copying machine 30 of FIG.

The image processing unit included in the copying machine 30 is
An image data input unit 70, an image processing unit 71, an image data output unit 72, a memory 73 including a RAM (random access memory), and a central processing unit (CPU) 74 are provided.

The image data input section 70 is a CCD section 70a,
It includes a histogram processing unit 70b and an error diffusion processing unit 70c.

The image data input section 70 is the CCD 42 shown in FIG.
Binary conversion of the image data of the original read from
While taking a histogram as a binary digital amount, the image data is processed by the error diffusion method and temporarily stored in the memory 73.

That is, in the CCD section 70a, after the analog electric signal corresponding to each pixel density of the image data is A / D converted, MTF correction, black and white correction or gamma correction is performed, and 256 gradations (8 (Bit) digital signal is output to the histogram processing unit 70b.

In the histogram processing unit 70b, the digital signal output from the CCD unit 70a is added for each pixel density of 256 gradations to obtain density information (histogram data), and if necessary, the obtained histogram. The data is sent to the CPU 74 and also to the error diffusion processing unit 70c as pixel data.

The error diffusion processing unit 70c uses the error diffusion method, which is a kind of pseudo halftone processing, that is, the method of reflecting the binarization error in the binarization judgment of adjacent pixels.
The 8-bit / pixel digital signal output from the unit 70a is converted into 1-bit (binary), and a redistribution operation for faithfully reproducing the local area density in the original is performed.

The image processing unit 71 includes multi-valued processing units 71a and 71b, a synthesis processing unit 71c, a density conversion processing unit 71d, a scaling processing unit 71e, an image processing unit 71f, an error diffusion processing unit 71g and a compression processing unit 71h. Contains.

The image processing unit 71 is a processing unit for finally converting the input image data into the image data desired by the operator, and the output image data finally converted into the memory 73. It is configured to be processed by this processing unit until it is stored as a data. However, each of the above-described processing units included in the image processing unit 71 functions as necessary and may not function.

That is, in the multilevel halftoning processing units 71a and 71b, the data binarized by the error diffusion processing unit 70c is converted again into 256 gradations.

In the synthesizing section 71c, a logical operation for each pixel, that is, an operation of logical sum, logical product or exclusive logical sum is selectively performed. The data that is the object of this calculation is the bit data from the pixel data and the pattern generator (PG) stored in the memory 73.

In the density conversion processing unit 71d, the relationship between the input density and the output density is arbitrarily set for the 256 gradation data signal based on a predetermined gradation conversion table.

In the scaling processing unit 71e, the pixel data (density value) for the scaled target pixel is obtained by performing interpolation processing according to the input known data according to the designated scaling ratio. After being obtained and the sub-scanning is scaled, the main-scanning is scaled.

In the image processing section 71f, various image processings can be performed on the input pixel data, and information extraction such as feature extraction can be performed on the data sequence.

The error diffusion processing unit 71g performs the same processing as the error diffusion processing unit 70c of the image data input unit 70.

In the compression processing section 71h, binary data is compressed by the encoding called run length. Also, image data
Regarding the compression of data, the compression works in the final processing loop when the final output image data is completed.

The image data output unit 72 includes a restoration unit 72a, a multi-value quantization processing unit 72b, an error diffusion processing unit 72c, and a laser output unit 72d.

The image data output unit 72 restores the image data stored in the memory 73 in the compressed state and restores the original 2
It is configured so that it is converted into 56 gradations again, error diffusion of 4-valued data that is a smoother halftone expression than 2-valued data is performed, and the data is transferred to the laser output unit 72d. There is.

Immediately, in the decompression unit 72a, the compression processing unit 71h.
The image data compressed by is restored.

In the multi-value quantization processing section 72b, the image processing section 71
Processing similar to that of the multi-value quantization processing units 71a and 71b is performed. In the error diffusion processing unit 72c, the image data processing unit 70
Processing similar to that of the error diffusion processing unit 70c is performed.

In the laser output section 72d, the digital pixel data is converted into a laser on / off signal on the basis of a control signal from a sequence controller (not shown), and the laser is output. Turns on / off.

The image data input unit 70 and the image data are input.
The data handled by the data output unit 72 is basically stored in the memory 73 in the form of binary data in order to reduce the capacity of the memory 73, but deterioration of the image data is taken into consideration. It is also possible to process in the form of 4-valued data.

FIG. 1 is a schematic sectional view in the vicinity of the duplex unit.

The sheet sent out from each sheet accommodating portion (not shown) is indicated by an arrow a from the lower right side of the duplex unit 11.
It is conveyed in the direction. When the sensor PSS detects the sheet from the sheet accommodating section, the transport roller J is once stopped and restarted at a timing with each of the other transport sections. The sheet that has passed the conveying / merging portion is conveyed to the image forming apparatus via the conveying roller H and the registration roller I. The registration roller I starts the operation in accordance with the image front end of the toner image formed on the photosensitive drum, and feeds the paper sandwiched between the nips.

The paper on which a predetermined image is stored on the recording surface side of the paper is ejected to the paper ejection tray side after passing through the fixing device, guided to the duplex unit side, or switched according to the copy mode. Be done.

This time, the sheet conveyed through the gate is guided to the duplex unit side 11. The sheet conveyed from the upper left portion of the duplex unit is once guided to the sheet inverting section 3. At this time, if the sensor DSI detects the leading edge of the paper,
Check the state of the solenoid DSOL1 and turn off the solenoid DSOL1 that the paper pressing plate 1 is acting on the trade-in feeding roller B side as shown in the figure. ) Is turned to.

That is, the sheet is retreated upward so as not to interfere with the sheet conveyance when the sheet is inserted. The side tray regulating plate 4 and the trailing edge regulating plate 5 are provided on the intermediate tray T of the sheet reversing section 3.
Is provided, and is configured to be movable back and forth and left and right according to the size of the paper sent to the reversing unit in advance.

For the sheet once stored in the sheet reversing section, the solenoid DSOL1 is turned on at the timing when the succeeding sheet is not conveyed to the sheet reversing section, and the sheet is transferred from above to the trade-in feeding roller B side (ON). Is pressed.

At this time, since the roller B is rotating in the direction of the arrow, the paper stored in the reversing unit is fed leftward. The sheets sent out by the trade-in feeding roller B are surely separated one by one by the sorting roller C so that they will not be double-fed. It is the friction member 6 that is in contact with the separating roller C, and if double feeding of paper occurs, only the bottommost paper is sent to the next process,
The other papers are prevented from being transported by the friction member 6.

The sensor DS2 is arranged to detect the leading edge of the separated sheet. If the sensor DS2 is not turned on within a predetermined time after the trade-in sheet feeding in the previous step, it is judged as a sheet feeding error. It is processed.

If the sensor DS2 is turned on within a predetermined time, it means that the operation is good and the process proceeds to the next step. After DS3 is turned on via the conveyance roller D and the conveyance roller E, after passing the conveyance roller F, the DS4 is turned on and the conveyance roller is conveyed when the leading edge of the sheet is caught in the conveyance roller G. -Stop La G and F. In this conveyance path, the length between the conveyance rollers G and F is set to at least one sheet length B5.

When the sensor DS3 is turned on for the succeeding sheet, one succeeding sheet (A4 or B5) is placed in the area between the sensor DS3 and the transport rollers D and E, and another succeeding sheet is the sensor DS2. When turned on, if the sheet is A4 or B5, the trailing edge portion of the succeeding other sheet is located in the sheet reversing section 3 from the roller D through the area of the sensor DS2 and the sorting roller C, and three sheets of paper are placed. The papers stop, respectively.

At this time, when the largest sheet, for example, A3 sheet, is stopped from the roller D to the area of the sensor DS2 and the sorting roller C, the trailing edge regulating plate is provided at the trailing edge of the sheet. It is located on the downstream side in the sheet discharge direction with respect to the position where the smallest sheet, for example, B5 sheet, is aligned in terms of length.

When all the sheets are A4 or B5, the three sheets before the fourth sheet are all stopped in the transport path and are accommodated in the sheet reversing section.

That is, the trailing edge portion of the third sheet and the fourth sheet partially overlap in the sheet reversing section. When the transport roller G is restarted while timing with the other transport rollers H and the registration roller I, the succeeding sheets are sequentially restarted.

Although all the paper sizes have been described as A4 and B5 this time, the paper sizes may be all A3 and B4, and A3, B4, A4 and B5 may be mixed.

When the sheet of A3 or B4 is stopped at the conveyance roller G at the beginning, it is about twice as long as the sheet of A4 or B5 and is conveyed from the conveyance roller G to the conveyance roller G. Will occupy. This state is the same regardless of which transport roller position is stopped.

That is, when the A4 or B5 sheet stops with the transport roller G at the head and the A3 or B4 sheet stops with the sensor DS3 at the head, the rear end of the A3 or B4 sheet reverses the sheet. Positioned at part 3 and stopped.

FIG. 5 shows an intermediate tray T which is provided in the paper inverting section 3 and accommodates the paper Y. The intermediate tray T is provided with a side edge regulating plate 4 and a rear edge regulating plate 5 which is movable (left and right directions in the drawing) according to the size of a sheet to be fed. The moving speed of the rear end regulating plate 5 is 2 in this embodiment.
It is 00 mm / sec, and the moving distance L is 210 mm or more when the size of the sheet is changed from A4 to A3.

In FIG. 2, the leading edge of the paper in the intermediate tray T is located at a position of about 11 mm from the center of the feeding roller B toward the sensor DS1 regardless of the size of the paper. The trailing edge of the sheets stored in the intermediate tray T from the position,
That is, the setting position of the rear end regulation plate 5 is about 1 in the case of B5.
82 mm, A4 is about 210 mm, and A3 is about 420 mm. The paper Y (A4) is carried out from the paper reversing unit 3 so as to be surely separated one by one by the roller C and the friction member 6, and the rear end of the paper Y stopped near the intermediate tray T. Is located on the downstream side of the trailing edge regulating plate 5 with respect to the sheet carry-out direction regardless of the size of the sheet.

Further, as shown in FIG. 1, when the sheet is accommodated in the sheet reversing section 3 and the sheet pressing plate 1 is operated at a predetermined sheet feeding timing to press the sheet against the trade-in roller B. When the sensor DS1 detects that the succeeding paper is coming into the paper reversing unit 3, the operations of the trade-in feeding roller B and the paper pressing plate 1 are once stopped.

That is, when the succeeding paper is sent toward the paper reversing section 3, the paper pressing plate 1 is retracted upward and priority control is performed so that the succeeding paper does not collide.

Finally, when the feeding of the sheet from the conveying roller G is restarted at the timing of the sheet sent from another conveying path, the sheet is fed through the conveying roller H and the registration roller I. The image is conveyed again to the image forming position, and another image different from the front surface is formed on the back surface of the paper.

The sheet on which the toner image is formed passes through the fixing section and is discharged to the sheet discharge tray side by the switching gate, and is temporarily stopped at a predetermined timing from the transport roller G in order. When the existing paper is fed again, the conveyance path of the duplex unit has a margin in the conveyance path by the length of the paper that has been fed out.

Therefore, the double-sided image recording apparatus next feeds a new paper from the cassette portion based on the size data of the paper fed from the transport roller G of the double-sided unit, The transport roller J is restarted at a proper timing to move it to the image recording position.

Next, the operation of the side end regulating plate 4 and the rear end regulating plate 6 will be described with reference to FIG.

The double-sided copy starts, the sheets are stored in the intermediate tray (6-1), and the side edge regulating plate 4 and the rear edge regulating plate 5 are aligned (6-2). At this time, if there is a next sheet to be copied, that is, if the size is changed (6-3, Y), and the next sheet to be copied is larger than the currently stored sheet (6-4, Y). ) Is changed after moving the trailing edge regulation plate 5 according to the size of the paper to be copied next (6-5) even if the intermediate tray still contains the paper when the aligning operation is completed. If the paper to be stored is smaller than the paper currently stored, the trailing edge regulation plate 5 is set to the leading end position for the next paper size when the last one of the papers in the intermediate tray is carried out from the intermediate tray. The movement is started toward (6-6), and the side edge regulating plate 4 and the rear edge regulating plate 5 are completely set to the next paper size (6-7). After this setting is completed, the next sheet is fed to the intermediate tray, but if the next sheet does not exist (6-3,
The matching operation ends in (N) (6-8).

When the sheet to be changed next is larger than the sheet currently stored, the operation for aligning the sheet to be copied next is performed immediately after the operation for aligning the sheet accommodated in the intermediate tray is completed. Alternatively, it may be carried out immediately after the completion of the aligning operation of the sheets until the time when the last one sheet in the intermediate tray is discharged from the intermediate tray.

As described above, by effectively utilizing the conveying path of the duplex unit, the processing efficiency in the duplex mode of the image duplexer can be greatly improved.

[0076]

The side edge regulating plate aligns the sheet received on the intermediate tray with respect to the width, and the trailing edge regulating plate aligns the received sheet with respect to the length at the first position. Is movable from the first position to the second position in which the other trays are aligned in length according to the other sheets to be received next by the intermediate tray. It is possible to prevent the oblique feeding at the time of paper feeding, reduce the copy processing time, and further improve the copy processing efficiency.

[Brief description of drawings]

FIG. 1 is a sectional view for explaining a sheet reversing unit of an embodiment of a copying machine of the present invention.

FIG. 2 is a cross-sectional view for explaining the operation of the paper reversing unit in FIG.

FIG. 3 is a sectional view showing a main part of an embodiment of a copying machine.

4 is a block diagram showing an image processing unit of the embodiment of the copying machine of FIG.

5 is a cross-sectional view for explaining a side edge regulating plate and a rear edge regulating plate of the sheet reversing unit of FIG.

6 is a flowchart showing the operation of the side edge regulating plate and the trailing edge regulating plate of the sheet reversing unit of FIG.

[Explanation of symbols]

 4 Side edge regulating plate 5 Rear edge regulating plate T Intermediate tray X, Y Paper

Claims (2)

[Claims] 1. An intermediate tray for receiving a sheet, a side edge regulating plate provided on the intermediate tray to align the sheet received in the intermediate tray with respect to the width, and the received sheet with respect to the length. To a second position on the intermediate tray for aligning the received sheets in length with a second position for aligning other sheets in length according to other sheets to be received next. A copying machine including a movable rear end regulating plate. 2. The first and second positions are the trailing edge of the stopped sheet when the sheet received by the intermediate tray is stopped near the intermediate tray after being discharged from the intermediate tray. The copying machine according to claim 1, wherein the copying machines are set so as to be located upstream of a copy unit with respect to the sheet discharge direction.