JP2000280580A - Image-forming apparatus and image formation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten a time FCOT before a first copied object is output without requiring a complicate circuit constitution or a complicate processing program. SOLUTION: In the copying apparatus, data of a read document is compressed and stored in a memory, read out from the memory and extended, so that a toner image is formed to an image carrier, transferred to a transfer paper and recorded. A CPU 100 controls to start to read out the document according to a copy start signal, compress and store the data of the read document in a memory 130, read out and extend the stored data in the memory, form the toner image to the image carrier, drive a first paper feed part to make a transfer paper wait at a second paper feed part beforehand to transfer the image when a transfer timing to the transfer paper which is inversely calculated from a specified number of lines corresponding to a time necessary from the start of reading the document to the extension reaches a timing after a time corresponding to the specified number of lines has passed, and drive the second paper feed part when the transfer timing to the transfer paper reaches the timing after the time corresponding to the specified number of lines has passed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus for forming an image on a recording material based on acquired image data,
More particularly, the present invention relates to an image forming apparatus and a method for compressing, temporarily storing acquired image data in an image storage unit, and then decompressing the image data to form an image.

[0002]

2. Description of the Related Art In an image forming apparatus, read image data is once compressed and stored in an image storage means.
The data stored in the image storage is expanded to form an image. At this time, after all the image data is read and stored, the image data is expanded to form an image.

[0003]

In such a configuration, for example, when an attempt is made to copy 20 originals, image formation is not performed while the image forming means is empty while reading images of as many as 20 originals. It was not started and the image was formed only after the reading was completed. Therefore, not only cannot the device be used efficiently, but also the time until the first image formation is completed (hereinafter also referred to as FCOT).
Will be reduced.

[0004] Therefore, the efficient use of equipment has been attempted and FC
The aim is to improve OT.

[0005]

The above object can be attained by the following constitution. (1) The invention according to claim 1 is a data acquisition unit for acquiring image data, a compression unit for compressing the image data acquired by the data acquisition unit to generate compressed data, and a compression unit generated by the compression unit. Image storage means for storing the compressed data stored therein, decompression means for decompressing the compressed data stored in the image storage means to generate decompressed data, and a recording medium on the recording material based on the decompressed data generated by the decompression means. In the image forming apparatus having an image forming means for forming an image, even if the data acquisition means is acquiring image data, the compressed data stored in the image storage means among the acquired image data is An image forming apparatus comprising: control means for controlling the image forming means to form an image based on the generated decompressed data. That.

According to a ninth aspect of the present invention, the image data acquired by the data acquisition means is compressed and stored in the image storage means, and the image data stored in the image storage means is expanded based on the decompressed data. In the image forming method in which the image forming unit forms an image on a recording material, even if the image data is being acquired by the data acquisition unit, the image data that is being acquired is stored in the image storage unit. An image forming method is characterized in that compressed data is decompressed and an image is formed by the image forming means.

According to these inventions, image formation can be performed even during acquisition of image data, and not only can the equipment be used efficiently, but also the FCOT can be increased.

Further, according to a second aspect of the present invention, the control means causes the image forming means to start image formation.
Before the acquisition of the image data by the data acquisition unit is completed, from the start of data acquisition of the data acquisition unit or from the start of storage of the compressed data in the image storage unit, after a lapse of a predetermined time or after a lapse of a predetermined line, It is characterized by performing.

According to the present invention, in addition to the first aspect, an image can be formed with accurate timing.
Good image formation can be performed. Further, claim 3
According to an aspect of the present invention, a storage unit that stores a recording material, a first paper supply unit that transports the recording material from the storage unit, and a recording material that is transported by the first paper supply unit are transmitted to the image forming unit. A sheet feeding unit having a second sheet feeding unit for sending out, and the control unit operates the first sheet feeding unit in advance, and causes the second sheet feeding unit to wait for a recording material; On the basis of the start of image formation by the image forming means, control is performed so that feeding by the second paper feed unit is started.

According to the present invention, in addition to the first or second aspect of the present invention, since the recording material is made to stand by, the FCOT can be further improved, and the timing with which the recording material is conveyed can be accurately taken. And a good image can be formed on the recording material.

Further, according to a fourth aspect of the present invention, there is provided a storage means for storing a recording material, a first paper supply unit for conveying the recording material from the storage means, and a recording medium conveyed by the first paper supply unit. And a second sheet feeding unit for feeding the sheet to the image forming unit. The control unit operates the first sheet feeding unit in advance and records the image on the second sheet feeding unit. While the material is kept on standby, the start of feeding by the second paper feeding unit is
Before the completion of the acquisition of the image data by the data acquisition unit, and after a lapse of a predetermined time or after a lapse of a predetermined line from the start of data acquisition by the data acquisition unit or from the start of storage of compressed data in the image storage unit It is characterized by the following.

According to the present invention, in addition to the first aspect of the present invention, since the recording material is put on standby, the FCOT can be further improved, and the timing of the conveyance of the recording material can be accurately determined. As a result, a good image can be formed on the recording material.

Further, according to a fifth aspect of the present invention, the control means causes the image forming means to start image formation.
This is performed based on the start of feeding by the second sheet feeding unit.

According to the present invention, in addition to the invention described in claim 4, an image can be formed with accurate timing.
Good image formation can be performed. Further, claim 6
In the invention described in (1), the predetermined time or the predetermined line is changed in accordance with a size of image data acquired by the data acquiring unit or an image forming speed in a sub-scanning direction by the image forming unit.

According to the present invention, in addition to the invention described in any one of claims 2 to 5, the image forming speed in the sub-scanning direction by the image forming means is changed even if the image forming means has various image data sizes. Even if it is, good image formation can be performed.

Further, according to a seventh aspect of the present invention, the image storage means can store data in the image storage means and read data from the image storage means in parallel. It is characterized by.

According to the present invention, in addition to the invention described in any one of the first to sixth aspects, the FCOT can be further improved. Further, the invention described in claim 8 is characterized in that the expansion means and the compression means are semiconductors integrally formed.

According to the present invention, in addition to the invention described in any one of the first to seventh aspects, the circuit configuration can be simplified.

[0019]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a configuration diagram showing a cross-sectional configuration of a copying machine which is an image forming apparatus used in an embodiment of the present invention.

Automatic document feeding means (hereinafter referred to as ADF)
A unit 10 automatically feeds and conveys a document in order to read one side or both sides of the document. Further, the image reading unit 20 which is a data acquisition unit has
Reading the image of the document being conveyed by F10,
This is means for acquiring image data. These ADF10
The image reading unit 20 can automatically read an image of a document and acquire image data.

More specifically, the original placement unit 11 of the ADF 10
A plurality of originals d are placed on the front side of the first original (first
Page) on top. Then, the roller 12
a, the first document is conveyed by the roller 13 via the roller 12b, and is rotated and conveyed around the roller 13.
At this time, the original surface (first surface) of the original d is illuminated by the light source 23 of the image reading unit 20 while being fixed below the second platen glass 22, and the reflected light is reflected by the mirror 24.
An image is formed on a light receiving surface of a CCD 28 serving as a photoelectric conversion unit via imaging optical systems 27 and 25. And roller 1
3. The image on the front side of the document being transported by the
The image data is obtained by photoelectric conversion by 28 and stored in the image memory 130 as described later. afterwards,
When reading an image on one side of the document, the document is discharged onto the discharge tray 16 with the surface facing downward. On the other hand, when reading the image on both sides of the document, the document is reversed via the reversing roller 14 and is again rotated and conveyed around the roller 13 by the roller 13. Is read. Then, the document whose front and back images have been read by the image reading unit 20 is again inverted by the reversing roller 14, and the paper output tray 16 is turned upside down.
The paper is ejected on top.

When an original is placed on the platen glass 21 with the reading surface facing down, the optical system (light source 23, mirrors 24, 25 and 26) is
1 so that reading can be performed by scanning along. Although the image reading unit 20 according to the present embodiment is configured to read the image of the document in the transport state, the document transported by the ADF 10 is placed on the platen glass 21 and is placed on the platen glass 21. The image of the document may be read by scanning the optical system. Furthermore, in the present embodiment, the data acquisition unit is configured by the image reading unit 20 that directly reads an image of a document, but is configured to acquire image data via a network interface or other interfaces. Is also good.

The image forming means is a means for forming an image on transfer paper p as a recording material. In the present embodiment, the image writing section 40 is used for forming an image by an electrophotographic method.
And an image forming unit 50. The image writing unit 40 forms a laser beam emitted from a laser diode (not shown) on the basis of image data read from the image memory 130 through a polygon mirror or the like (not shown) based on image data read from the image memory 130 as described later. Photoreceptor drum 51 of section 50
This is a means for performing a scanning exposure on the top to form a latent image. The surface of the photosensitive drum 51, which is an image carrier of the image forming unit 50, is uniformly charged by the charging unit 52, and a latent image is formed by the laser light from the image writing unit 40 described above. . The formed latent image is developed by the developing unit 53 with toner, and a visible toner image is formed on the photosensitive drum 51.

The toner image formed on the photosensitive drum 51 is transferred by a transfer unit 54 onto a transfer sheet p separately conveyed by sheet feeding means described later. Then, the transfer paper p on which the toner image has been transferred is separated by the separating unit 55.
The toner image on the transfer paper p is separated from the photosensitive drum 51 and is conveyed to the fixing unit 59 by the conveyance mechanism 58, and the fixing unit 59 fixes the toner image on the transfer paper p by the action of heat and pressure. An image is formed thereon. The transfer sheet p on which the toner image has been fixed is discharged outside the apparatus by a discharge roller 65. If necessary, the transfer sheet p is guided by a guide 61 to reverse the front and back of the transfer sheet p. 65
The paper p is ejected out of the apparatus, or enters the reversing unit 63 via the guide 61, and the transfer paper p entering the reversing unit 63
May be reversely conveyed, turned over, and conveyed again to the image forming unit 50 to form an image on both sides of the transfer paper p. On the other hand, the photosensitive drum 51 on which the toner image has been transferred onto the transfer paper further rotates, and the photosensitive drum 51
The toner remaining on the top is removed by the cleaning unit 56,
The next image formation is performed.

Incidentally, the transfer paper p is stored in a state of being stacked on each of the paper feed cassettes 30a to 30c as storage means. Then, the transfer paper p stored in the paper feed cassettes 30a to 30c is transported from the paper feed cassettes 30a to 30c to the image forming unit 50 by the paper feeding unit. In this case, the paper feeding means includes the paper feeding cassettes 30a to 30a.
The first paper feed rollers 181a to 181c, which are the first paper feed units that convey the transfer paper p from 30c, the first paper feed roller 181a
Transfer sheet p conveyed by the image forming unit 50
And a second paper feed roller 182 that is a second paper feed unit that conveys the paper to the printer. Then, prior to image formation, the first
One of the paper feed rollers 181a to 181c is driven, and the transfer paper p conveyed from the corresponding paper feed cassettes 30a to 30c waits at the position of the second paper feed roller 182 (registration wait), and thereafter, the photosensitive member The second paper feed roller 182 is configured to start driving so as to synchronize with the toner image formed on the drum 51.

Next, a description will be given with reference to FIG. 2 which is a block diagram showing an example of the electrical configuration of the above-described image forming apparatus. In FIG. 2, the double line represents the flow of image data.

The CPU 100 is control means for controlling each section of the image forming apparatus, and controls each section according to a processing program (not shown). The operation unit 110 is an external input unit that performs various operations such as selection and designation of the number of copies, enlargement / reduction ratio, transfer paper, etc., and start of copying. The operation result is transmitted to the CPU 100. The ADF control unit 120 calculates C
An ADF control unit that controls the ADF 10 according to an instruction from the PU 100. Read image processing unit 140
Represents the image data read by the image reading unit 20;
Image processing means for sequentially performing image processing.

The image memory 130 is image storage means for storing image data, and here, is a memory for storing image data (hereinafter, referred to as compressed data) compressed by a compression / expansion circuit 150 described later. In this embodiment, the image memory 130 can be configured as a dual-port memory capable of performing storage (storage) and reading (output) in parallel, that is, capable of simultaneously storing and reading. It is preferable because the processing speed and FCOT can be improved.

The compression / expansion circuit 150 includes the image reading unit 2
0, and compresses the image data processed by the read image processing unit 140 to generate compressed data, and expands the compressed data stored in the image memory 130 to reproduce the image data ( This is compression / expansion means for performing expansion means (reproduced image data is referred to as expansion data). In the present embodiment, the circuit configuration can be simplified by using the compression / expansion circuit 150 which is a semiconductor in which each circuit of the compression means and the expansion means is integrally formed. Further, the compression / expansion circuit 150 can drive (function) independently of compression and expansion.
In other words, it is a semiconductor device that can simultaneously perform compression and expansion. However, the compression / decompression circuit 15
0 may be composed of separate semiconductors for the compression circuit and the expansion circuit.

The recording image processing unit 160 includes a compression / expansion circuit 1
Image processing means for performing image processing on the decompressed data expanded by 50 for image formation. Also, the paper feed control unit 170
Is a paper feed control unit that controls the paper feed roller 180 including the above-described first paper feed rollers 181a to 181c and the second paper feed roller 182 according to an instruction from the CPU 100.

Here, the timing of image reading, storage / output to the image memory 130, image formation, paper feeding, etc. in the present embodiment is shown in FIG. 3 which is a time chart, and the compression stored in the image memory 130. The state of the data will be described based on FIG. 3A shows the pressed state of the copy button provided on the operation unit 110, FIG. 3B shows the image reading timing by the image reading means 20, and FIG. 3C shows the image data by the compression / expansion circuit 150. (Read image processing unit 1
40 shows the timing of compression of the image data processed by the image processing 40 and storage (storage) of the compressed data in the image memory 130. FIG. (E) shows the timing of decompression of the compressed data, and (e) shows the photosensitive drum 5 based on the decompression data (image data processed by the recording image processing unit 160) by the image writing unit 40.
1, (f) indicates the drive timing of the first paper feed rollers 181a to 181c,
(G) shows the drive timing of the second paper feed roller 182, and (h) shows the transfer timing of the toner image formed on the photosensitive drum 51 by the transfer unit 54 onto the transfer paper p. In this embodiment, the transport speed of the transfer paper p by the first paper feed rollers 181a to 181c is the transport speed of the transfer paper p by the second paper feed roller 182 (the peripheral speed of the photosensitive drum 51, Image forming speed) 2
It is twice.

First, when the operator presses a copy button provided on the operation unit 110, a copy start signal is output from the operation unit 110 (FIG. 3A). In response to the copy start signal, the CPU 100 and the sheet feeding control unit 170
Operates the first paper supply unit (any one of the first paper supply rollers 181a to 181c) to convey the transfer paper p to the second paper supply unit (second paper supply roller 182). Roller 18
At the position 2, the transfer paper p is kept waiting (register waiting). That is, prior to image formation, the first paper supply unit is operated in advance, and the transfer paper p is made to wait in the second paper supply unit.

On the other hand, the CPU receiving the copy start signal
100 issues an instruction to the ADF control unit 120 to carry the document d. As described above, the ADF control unit 120 transmits the document d placed on the document placing unit 11 so as to carry the document d. Control. At this time, the CPU 100
Also controls the document reading unit 20 to read the image of the document d being conveyed in synchronization with the document d conveyed by the ADF 10 as described above (see FIG. 3).
(B) One page of image data is sequentially read. Image data obtained by reading by the image reading unit 20 is subjected to predetermined image processing by a read image processing unit 140, and then compressed by a compression / expansion circuit 150 to generate compressed data. Memory 13
0 is stored (stored) in FIG. 3 (FIG. 3C).

At this time, the image data read by the image reading section 20 is subjected to image processing and compression, and is sequentially stored in the image memory 130 in the direction indicated by the arrow from the reading start position. That is, the image processing, compression, and storage are not performed after all the image data for one page is read by the image reading unit 20.
Image processing, compression, and storage are sequentially performed from the image data read out of the image data for the page.

In the present embodiment, even when the image data for one page is being read by the image reading unit 20, the compressed data stored in the image memory 130 among the image data being read is stored. , So that image formation can be performed. That is, while storing the compressed data in the image memory 130, the already stored compressed data is decompressed by the compression / decompression circuit 150, and the generated decompressed data is subjected to predetermined image processing by the recording image processing unit 160. The latent image is output to the image writing unit 40 and forms a latent image on the photosensitive drum 51 as described above. With this configuration, it is not necessary to wait for image formation until reading of image data of at least one page is completed, so that not only can the device be used efficiently, but also the FCOT can be increased. it can.

More specifically, the image reading unit 20
After a predetermined number of lines have passed from the start of reading (when reading is completed up to the position in FIG. 4), the CPU 100 controls
The compression / expansion circuit 150 reads out the compressed data already stored in the image memory 130 (from the position shown in FIG. 4) and decompresses it to generate decompressed data. And
The decompressed data is output to the image writing unit 40 after performing predetermined image processing in the recording image processing unit 160,
As described above, the image writing unit 40 starts writing (FIG. 3E), and forms a latent image on the photosensitive drum 51.

Here, the number of lines means the image reading unit 2
0 CCD 28 is a line CCD, and reads an image of a document line by line.
Is the number of lines in a direction orthogonal to the direction in which the document moves (in this embodiment, the direction in which the document moves, generally called the sub-scanning direction). The predetermined number of lines is stored in advance in a storage unit (not shown), and the number of lines stored in the storage unit and the image reading unit 20.
When the number of lines of the image data read in step 1 matches, the reading of the compressed data from the image memory 130 is started as described above.

The predetermined number of lines is determined by the size of the image data read by the image reading unit 20 or
The size of the image data or the image forming speed is stored in the storage unit so as to be changed according to the image forming speed in the sub-scanning direction by the image forming unit 50 (in the present embodiment, the peripheral speed of the photosensitive drum 51). , A plurality of predetermined lines are stored, and from among the plurality of predetermined lines, a predetermined number of lines for an image to be currently formed is appropriately selected. This is because, when the image reading speed of the image reading unit 20 and the image forming speed of the image forming unit 50 match, the image formed by the image forming unit 50 is replaced by the image read by the image reading unit 20. It does not catch up, but if these speeds do not match, catching up and inconvenience will occur, so that this is avoided.

In this embodiment, the decompression is started after a predetermined number of lines have elapsed from the start of reading. However, after the decompression is performed in advance and temporarily stored in a buffer or the like, the predetermined number of lines are read from the start of reading. After the passage of time, the formation of a latent image on the photosensitive drum 51 may be started.

On the other hand, the compressed data is read out from the image memory 130 and decompression is started so that the transfer paper p waiting on the second paper feed roller 182 is synchronized with the toner image formed on the photosensitive drum 51. (Or in this case, it may be based on the start of writing), re-feeding is started. That is, the start of feeding by the second sheet feeding roller 182 is controlled by the CPU 100 and the sheet feeding control unit 170 based on the reading of compressed data from the image memory 130 and the start of decompression (FIG. 3 (g)). Thereafter, as described above, the toner image on the photosensitive drum 51 is transferred to the transfer paper p (FIG. 3 (h)).

As described above, in the present embodiment, even when the image data is being read by the image reading section 20, the compressed data stored in the image memory 130 among the image data being read is compressed. Since the image is formed based on the decompressed data generated by decompression at 150, the image can be formed without waiting for reading of all the image data. Can be improved. In particular,
Start of image formation by image forming unit 50 (in the present embodiment, generation of decompressed data by compression / decompression circuit 150 is started, but latent image may be started by image writing unit 40).
This is performed before the image data is completely read by the image reading unit 20 and after a predetermined line has elapsed from the start of the image data reading by the image reading unit 20, so that the image formation can be performed with more accurate timing. And good image formation.

The first paper feed rollers 181a-18
1c, the transfer paper p is kept on standby by the second paper feed roller 182, and the feeding by the second paper feed roller 182 is started based on the start of image formation by the image forming unit 50. Therefore, the FCOT can be further improved, and the timing of the transfer of the transfer paper p can be accurately set, so that a good image can be formed on the recording material. In the present embodiment, the start of re-feeding of the second paper feed roller 182 is performed based on the start of image formation by the image forming unit 50. However, based on the start of image data reading by the image reading unit 20. May be performed.

Next, a modification of the above-described embodiment will be described with reference to a time chart of FIG.
In the above-described embodiment, the second sheet feed roller 182 is configured to start re-feeding after the image forming by the image forming unit 50 has precedently performed. Image formation by the image forming unit 50 is performed after the start of re-feeding at 182 precedes. Other configurations are the same as those of the above-described embodiment, and therefore may be omitted in the following description. In the case of the present modification, the distance between the transfer unit 54 and the second paper feed roller 182 is set to be longer than that of the above-described embodiment, that is, the transfer unit 54 and the image writing The length of the peripheral surface of the photosensitive drum 51 between the writing position on the photosensitive drum 51 by the unit 40 is larger than the transport distance of the transfer paper p between the transfer unit 54 and the second paper feed roller 182. It is getting longer.

First, a copy start signal is output from the operation unit 110 based on the pressing of the copy button by the operator (FIG. 5A). In response to the copy start signal, one of the first paper feed rollers 181a to 181c operates to convey the transfer paper p to the second paper feed roller 182, and keep the transfer paper p on standby.

On the other hand, based on the copy start signal, A
The DF 10 conveys the original document d placed thereon. At this time, in synchronization with the document d conveyed by the ADF 10,
The image reading unit 20 starts reading the image of the conveyed document (FIG. 5B), and sequentially reads one page of image data. The image data read by the image reading unit 20 is subjected to predetermined image processing by a read image processing unit 140, and then compressed by a compression / expansion circuit 150.
Compressed data is generated, and the compressed data is stored in the image memory 1
30 is stored (stored) in the memory 30 (FIG. 5C).

In the present modified example, as in the above-described embodiment, even when the image reading unit 20 is in the process of reading one page of image data, the image memory of the image data being read is stored. It is configured such that image formation can be performed based on the compressed data stored in 130. That is, while storing the compressed data in the image memory 130, the already stored compressed data is decompressed by the compression / decompression circuit 150, and the generated decompressed data is subjected to predetermined image processing by the recording image processing unit 160. The latent image is output to the image writing unit 40 and forms a latent image on the photosensitive drum 51 as described above. With this configuration, it is not necessary to wait for image formation until reading of image data of at least one page is completed, so that not only can the device be used efficiently, but also the FCOT can be increased. it can.

More specifically, in this modified example, the photosensitive drum 51 is located between the transfer unit 54 and the writing position on the photosensitive drum 51 by the image writing unit 40.
First, the peripheral surface length is longer than the transport distance of the transfer paper p between the transfer unit 54 and the second paper feed roller 182. (Start of transfer of the transfer paper p waiting).
Therefore, the reading of image data by the image reading unit 20 is controlled by the CPU 100 and the sheet feeding control unit 170 after a lapse of a predetermined number of lines from the start of reading.
The feeding of the transfer paper p by the second paper feed roller 182 is started (FIG. 5G).

Then, based on the start of refeeding, the compression / expansion circuit 150 reads out the compressed data already stored in the image memory 130 and decompresses it to generate decompressed data. The decompressed data is transmitted to the recording image processing unit 1
After performing predetermined image processing in 60, the image writing unit 4
0, and as described above, the image writing unit 40
Starts writing (FIG. 5E), and the photosensitive drum 51
A latent image is formed thereon.

The predetermined number of lines in this modification is
This is the same as the predetermined number of lines in the present embodiment described above,
Further, reading of compressed data from the image memory 130,
Decompression, image processing, writing, and furthermore, the photosensitive drum 51
Is the number of lines in consideration of the movement to the transfer unit 54 and the like.

Of course, as in the above-described embodiment, the predetermined number of lines is determined by the size of the image data read by the image reading unit 20 or the image forming speed in the sub-scanning direction by the image forming unit 50 (this embodiment). In the embodiment, the distance is changed according to the peripheral speed of the photosensitive drum 51).

Thereafter, the toner image formed on the photosensitive drum 51 is transferred onto the transfer paper p re-conveyed from the second paper feed roller 182 (FIG. 5 (h)). As described above, in the present modification, even when image data is being read by the image reading unit 20, compressed data stored in the image memory 130 among image data being read is expanded by the compression / expansion circuit 150, Since image formation is performed based on the generated decompressed data, image formation can be performed without waiting for reading of all image data, and not only can the device be used efficiently, but also the FCOT can be improved. Can be. In particular, in the present modified example, one of the first paper feed rollers 181a to 181c is operated in advance, and the transfer paper p is made to stand by by the second paper feed roller 182, and
Since the start of feeding by the second paper feed roller 182 is performed before the image reading of the image reading unit 20 is completed and after a predetermined line has elapsed from the start of reading by the image reading unit 20, the FCOT of the FCOT is started. Further improvement can be achieved, and the timing of the transfer of the transfer paper p can be accurately set, so that a good image can be formed on the recording material.

Further, the start of image formation by the image forming section 50 (in this modified example, the generation of decompressed data by the compression / decompression circuit 150 is started, but the start of a latent image by the image writing section 40 may also be performed) Since the transfer is performed based on the start of feeding by the paper roller 182, image formation can be performed at an accurate timing, and good image formation can be performed.

In the above-described embodiment or modification, after a predetermined number of lines have elapsed from the start of reading by the image reading section 20, the start of image formation or the start of re-feeding by the second feed roller 182 is performed. However, instead of the number of lines, a predetermined time may have elapsed. Further, in the above-described embodiment or the modified example, the reading by the image reading unit 20 is started at the beginning of the predetermined number of lines, but the compression is started by the compression / expansion circuit 150 or the compressed data compressed by the compression / expansion circuit 150 is started. May be set as the start of storage in the image memory 130, and may be the predetermined number of lines from this start.

Further, in the conventional image forming apparatus,
The image data read by the image reading unit 20 is compressed and supplied to the image writing unit 40 without temporarily storing the image data in the image memory 130. Alternatively, in a modified example, even if an extra signal path for performing the through operation is not provided, parallel processing equivalent to the through operation is performed, and the FCOT can be improved. Of course, at this time, cost reduction can also be realized.

[0055]

As described in detail above, according to the present invention,
Efficient use of equipment can be achieved, and FCOT can be improved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating a mechanical configuration of an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a functional block diagram illustrating an electrical configuration of the image forming apparatus according to the embodiment of the present invention.

FIG. 3 is a time chart illustrating a state of each unit during operation of the image forming apparatus according to the exemplary embodiment of the present invention.

FIG. 4 is an explanatory diagram showing a state of a specified number of lines in the embodiment of the present invention.

FIG. 5 is a time chart showing the state of each unit during operation of the image forming apparatus according to the embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 10 ADF (Automatic Document Feeding Means) 20 Image Reading Unit 30 Paper Feeding Unit 40 Image Writing Unit 50 Image Forming Unit 60 Inverting Unit 80 Transport Drive Circuit 100 CPU 110 Operating Unit 120 ADF Control Unit 130 Image Memory 140 Read Image Control Unit 150 Compression / expansion circuit 160 Recorded image processing unit 170 Feed control unit 180 Feed roller 181 First feed roller 182 Second feed roller

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 1/00 H04N 1/04 107Z 5C062 1/04 107 G03G 21/00 372 5C072 (72) Inventor Minoru Asakawa 2970, Ishikawa-cho, Hachioji-shi, Tokyo F-term within Konica Corporation (reference) CA01 CB07 CB09 HB07 3F102 AA01 AB01 BA02 BA07 BB02 CB01 DA08 EA03 FA08 5C062 AA05 AB17 AB22 AB42 AC02 AC04 AC13 AC22 AC25 AC59 5C072 AA03 BA03 HA12 NA04 NA08 UA08 UA11

Claims (9)

[Claims] A data acquisition unit that acquires image data; a compression unit that compresses the image data acquired by the data acquisition unit to generate compressed data; and an image that stores the compressed data generated by the compression unit. Storage means; decompression means for decompressing compressed data stored in the image storage means to generate decompression data; image formation for forming an image on a recording material based on decompression data generated by the decompression means In the image forming apparatus having means, even while the data acquisition means is acquiring image data,
Control means for decompressing the compressed data stored in the image storage means among the image data being acquired by the decompression means and controlling the image forming means to form an image based on the generated decompression data; An image forming apparatus comprising: 2. The image forming apparatus according to claim 1, wherein the control unit starts image formation by the image forming unit before image data acquisition by the data acquisition unit is completed, and starts from the data acquisition start of the data acquisition unit or the compressed data. 2. The image forming apparatus according to claim 1, wherein the processing is performed after a lapse of a predetermined time or after a lapse of a predetermined line from the start of storage in the image storage unit. 3. A storage unit for storing a recording material, a first paper supply unit for conveying the recording material from the storage unit, and sending out the recording material conveyed by the first paper supply unit to the image forming unit. A sheet feeding unit having a second sheet feeding unit, wherein the control unit operates the first sheet feeding unit in advance to cause the second sheet feeding unit to wait for a recording material, and 3. The image forming apparatus according to claim 1, wherein control is performed such that feeding by the second sheet feeding unit is started based on the start of image forming by the image forming unit. 4. 4. A storage unit for storing a recording material, a first paper supply unit for conveying the recording material from the storage unit, and sending the recording material conveyed by the first paper supply unit to the image forming unit. A sheet feeding unit having a second sheet feeding unit, wherein the control unit operates the first sheet feeding unit in advance to cause the second sheet feeding unit to wait for a recording material, and The start of feeding by the second paper feeding unit is performed before the completion of image data acquisition by the data acquisition unit and from the start of data acquisition by the data acquisition unit or from the start of storage of compressed data in the image storage unit. 2. The image forming apparatus according to claim 1, wherein the processing is performed after a predetermined time has elapsed or after a predetermined line has elapsed. 5. The image forming apparatus according to claim 4, wherein the control unit starts image formation by the image forming unit based on start of feeding by the second sheet supply unit. . 6. The predetermined time or the predetermined line,
6. The image forming apparatus according to claim 2, wherein the size of the image data is changed according to a size of the image data acquired by the data acquiring unit or an image forming speed in a sub-scanning direction by the image forming unit. apparatus. 7. The image storage device according to claim 1, wherein said image storage device can store data in said image storage device and read data from said image storage device in parallel. The image forming apparatus according to any one of the above. 8. The semiconductor device according to claim 1, wherein said expansion means and said compression means are semiconductors integrally formed.
8. The image forming apparatus according to any one of claims 1 to 7, 9. The image forming apparatus according to claim 1, wherein the image data acquired by the data acquiring unit is compressed and stored in the image storing unit. In the image forming method for forming an image, even while image data is being acquired by the data acquisition unit,
An image forming method comprising: decompressing compressed data stored in the image storage unit of the image data being acquired, and forming an image by the image forming unit.