JPH09186834A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manage a storage area with good efficiency by selecting a minimum unit according to the size of an image signal and performing storing operation according to the selected minimum unit. SOLUTION: A hard disk consists roughly of three areas which are a management data area, a document image data area, and a stamp image data. Then 1-bit flags are prepared by blocks in the defective block management area, and if a defective block is found, the bit corresponding to its block number is set to manage the defective block place. When equipment is powered ON, defective block management data are read in a memory and for ordinary copying operation, the copy in this memory is referred to. When a defective block is registered, the management data in the memory are updated and even the hard disk is written to maintain the identity of the defective block management data. Consequently, when an image signal which is different in size is read, the use efficiency of the storage drvice can be increased.

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 using a storage device for digital image signals.

[0002]

2. Description of the Related Art Conventionally, image forming apparatuses, especially digital image forming apparatuses in recent years, have a storage device for storing a large amount of image signals. This is because various processes are executed on the image signal. The most popular mass storage device at present is a hard disk device. In order to efficiently manage a large amount of image data, the hard disk device is capacity-divided into predetermined minimum allocation units to manage storage and reproduction.

A typical minimum allocation unit is usually a sector of 512 bytes. If the allocation of hard disk devices is managed in very small units, the amount of management information required will increase. For this reason, it is often managed in units of blocks in which a plurality of sectors are grouped together.

Generally, a hard disk has defective sectors that cannot be normally read / written due to minute defects on the storage medium. Therefore, in the present embodiment, if there is at least one defective sector in the block, the block is registered as a defective block, and it is configured so that image data will not be written to such a defective block during a normal copy operation. ing. In a network file server, etc., a verify operation is performed after writing data to check if writing was successful. If an error occurs, that area is registered as a bad sector and at the same time the data to be written is written to another sector. Such hot fix operation is realized. However, in the case of a copying machine, it is not allowed that the copy productivity will decrease due to the occurrence of a hard disk access error.Therefore, the operation to check for defective sectors during factory shipment and during idle time such as copy standby state is performed. There is.

[0005]

However, the types of image data handled by the image forming apparatus are diversified, and with this diversification, the data amount of the image data greatly differs between large and small. For example, the original image data is on the order of several MB even if compressed, whereas the user stamp image is about 1 KB per stamp. If these image data are managed by uniformly allocating the storage capacity, there is a problem that the utilization efficiency of the storage device is lowered.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image forming apparatus which improves the efficiency of use of a storage device when handling image signals of different sizes.

[0007]

In order to achieve the above object, the image forming apparatus of the present invention has a storage means for storing a digitally converted image signal, and manages the image signal by dividing it into a predetermined minimum unit. The management means selects a minimum unit according to the size of the image signal, and manages the storage in the storage means based on the selected minimum unit.

The storage means may be a hard disk device.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of an image forming apparatus according to the present invention will be described in detail with reference to the accompanying drawings. FIG.
FIG. 11 to FIG. 11 show an embodiment of the image forming apparatus of the present invention.

1 to 4 are a schematic diagram of an image forming apparatus of the present embodiment, a schematic diagram of an operation unit, and a block diagram. In the image forming apparatus of FIG. 1, an automatic document feeder (hereinafter referred to as A
When the start key 34 on the operation unit 30 is pressed, the document stack placed on the document table 2 in the DF) 1 is fed from the lowermost document to the feeding roller 3, The feed belt 4 feeds the contact glass 6 to a predetermined position. After the image data of the original document on the contact glass 6 is read by the reading unit 50, the original document that has been read is ejected by the feeding belt 4 and the ejection roller 5. Further, when the document set detection 7 detects that the next document is present on the document table 2, the document is fed onto the contact glass 6 in the same manner as the previous document. The feeding roller 3, the feeding belt 4, and the discharging roller 5 are driven by the conveyance motor 26.

The transfer sheets stacked on the first tray 8, the second tray 9, and the third tray 10 are fed by a first paper feeding device 11, a second paper feeding device 12, and a third paper feeding device 13, respectively. ,
The sheet is transported by the vertical transport unit 14 to a position where it contacts the photoconductor 15. The image data read by the reading unit 50 is written on the photoconductor 15 by the laser from the writing unit 57, and passes through the developing unit 27 to form a toner image. And
The transfer paper transfers the toner image on the photoconductor 15 while being conveyed by the conveyance belt 16 at the same speed as the rotation of the photoconductor 15. After that, the image is fixed by the fixing unit 17,
The paper is discharged to the outside of the post-processing device by the paper discharge unit 18.

When images are formed on both sides of the transfer paper, the transfer paper fed from each of the paper feed trays 8 to 10 and formed into an image is not guided to the paper discharge tray 104 side, but is branched for path switching. By setting the claw 112 on the upper side, the paper is once stocked in the double-sided paper feeding unit 111. After that, the transfer paper stocked in the double-sided paper feeding unit 111 is re-fed from the double-sided paper feeding unit 111 in order to transfer the toner image formed on the photoconductor 15 again, and a branching claw for path switching. 112 is set on the lower side and is guided to the paper discharge tray 104. The double-sided sheet feeding unit 111 is used when images are formed on both sides of the transfer sheet in this way.

The photoconductor 15, the conveyor belt 16, the fixing unit 17, the paper discharging unit 18, and the developing unit 27 are driven by a main motor 25, and the paper feeding devices 11 to 13 drive the main motor 25 respectively. ~ 24
Driven by transmission. The vertical transport unit 14 is driven to transmit the drive of the main motor 25 by the intermediate clutch 21.

FIG. 2 is a diagram showing the operation unit 30. The operation unit 30 includes a liquid crystal display 31, a numeric keypad 32,
A clear / stop key 33, a print key 34, and a mode clear key 35 are provided, and the liquid crystal display 31 displays function keys 37, the number of copies, and a message indicating the state of the image forming apparatus.

FIG. 3 shows a liquid crystal display 31 of the operation unit 30.
It is a figure showing an example of a display of. When the operator touches the key displayed on the liquid crystal display 31, the key indicating the selected function is highlighted in black. Further, when the details of the function must be designated (for example, the scaling value for scaling), the detailed function setting screen is displayed by touching the key. As described above, since the liquid crystal display uses the dot display device, it is possible to graphically perform the optimum display at that time.

FIG. 4 mainly shows the main controller 20.
3 is a diagram of a control device. Main controller 2
0 controls the entire image forming apparatus. The main controller 20 includes an operation unit 30 that performs display for an operator and input control of function setting from the operator, control of a scanner,
An image processing unit (IPU) 4 for controlling the writing of a document image in the image memory and the control of forming an image from the image memory
9, a distributed control device such as an automatic document feeder (ADF) 1 is connected.

Each distributed control device and main controller 20
Exchanges machine status and operation commands as needed. Further, it is connected to the main motor 25 and various clutches 21 to 24 necessary for paper conveyance and the like. Using Figure 1,
The image reading means and the operation of forming an image on the recording surface in the present embodiment will be described. Note that the latent image is a potential distribution generated by converting an image into optical information and irradiating the image on the photoconductor surface.

The reading unit 50 is composed of a contact glass 6 on which a document is placed and an optical scanning system. The optical scanning system includes an exposure lamp 51, a first mirror 52, a lens 53, a CCD image sensor 54, and the like. The exposure lamp 51 and the first mirror 52 are fixed on a first carriage (not shown), and the second mirror 55 and the third mirror 56 are fixed on a first carriage (not shown). When reading a document image, the first carriage and the second carriage are mechanically scanned at a relative speed of 2: 1 so that the optical path length does not change. This optical scanning system is driven by a scanner drive motor (not shown). The original image is
It is read by the CCD image sensor 54, converted into an electric signal and processed. By moving the lens 53 and the CCD image sensor 54 in the left-right direction in FIG. 2, the image magnification is changed. That is, the lens 53 and the CCD image sensor 54 correspond to the designated magnification.
The position is set in the left-right direction.

The writing unit 57 is composed of a laser output unit 58, an imaging lens 59 and a mirror 60. Inside the laser output unit 58, a rotary polygon mirror which rotates at a high speed and a constant speed by a laser diode which is a laser light source and a motor. (Polygon mirror) is equipped. Laser light emitted from the laser output unit 58 is polarized by a polygon mirror that rotates at a constant speed, passes through an imaging lens 59,
The light is folded back by the mirror 60, and a focused image is formed on the surface of the photoconductor.

The polarized laser light is exposed and scanned in a direction (main scanning direction) orthogonal to the direction in which the photosensitive member rotates, and the image signal output from the selector 64 of the image processing unit, which will be described later, is recorded line by line. . An image (electrostatic latent image) is formed on the photoconductor surface by repeating main scanning at a predetermined cycle corresponding to the rotation speed and the recording density of the photoconductor.

As described above, the laser light output from the writing unit 57 is applied to the photoconductor 15 of the image forming system. Although not shown, a beam sensor that generates a main scanning synchronization signal is disposed at a position near one end of the photoconductor 15 where the laser beam is irradiated. Based on the main scanning synchronization signal, control of image recording start timing in the main scanning direction and generation of a control signal for inputting and outputting an image signal described later are performed.

Image processing unit (IPU) in this embodiment
The configuration of 49 will be described with reference to FIG. The light emitted from the exposure lamp 51 illuminates the document surface, and the reflected light from the document surface is imaged and received by a CCD image sensor 54 by an imaging lens (not shown) and photoelectrically converted to A / A. D
The converter 61 converts the digital signal. The image signal converted into the digital signal is subjected to the shading correction 62.
After this, the image processing unit 63 performs MTF correction, γ correction, and the like. In the selector 64, the destination of the image signal is switched to the scaling unit 71 or the image memory controller 65. The image signal that has passed through the scaling unit 71 is scaled according to the scaling ratio and is written in the writing unit 57.
Sent to Image memory controller 65 and selector 6
Image signals can be input and output bidirectionally between the four sections. Although not explicitly shown in FIG. 5, the image processing unit (I
The PU) has a function of selecting input / output of a plurality of data so that image data supplied from the outside in addition to image data input from the reading unit 50 can be processed. For example, it is data output from a data processing device such as a personal computer.

CP for setting the image memory controller 65, etc., and controlling the reading section 50 and the writing section 57
U68 and ROM for storing its programs and data
69 and RAM 70. Further, the CPU 68 can write and read the data of the image memo 66 via the memory controller 65.

Details of the memory controller 65 and the image memory 66 shown in FIG. 5 will be described with reference to FIG. The memory controller 65 has blocks of an input data selector 101, an image composition 102, a primary compression / expansion 103, an output data selector 104, and a secondary compression / expansion 105. The control data is set in each block by the CPU 68. Addresses and data in FIG. 5 represent signals relating to image data, and data and addresses relating to control / drive of the CPU 68 are not shown.

The image memory 66 comprises primary and secondary storage devices (106, 107). Primary storage device 106
Allows data to be written to the memory at substantially the same speed as the input image data transfer rate, or data to be read from the memory at the time of image output at a high speed substantially at the same time as the data transfer rate required at the time of input / output. , A high-speed accessible memory such as DRAM is used. Further, the primary storage device 106 has a configuration (interface unit with the memory controller 65) that can be divided into a plurality of areas according to the size of image data to be processed and can simultaneously input and output image data. .

The secondary storage device is composed of a hard disk device (hereinafter also referred to as HDD) 107, and is a large-capacity memory for storing data in order to combine and sort input images. If the primary storage device 106 has sufficient capacity to process the image data, H
No data is input or output to or from the DD 107. HDD1
If 07 can write / read data substantially in synchronization with the data transfer rate required at the time of image input / output,
Input / output image data can be directly written in the HDD 107 or read from the HDD 107. Also, 1
Data can be processed without distinction between secondary and secondary. HDD
Even if the data writing / reading of the data 107 is not possible in synchronism with the data transfer rate required at the time of image input / output, for example, when a recording medium such as a hard disk or a magneto-optical disk is used for the HDD 107, the HDD
By interposing a primary storage device for input / output of 07 data, processing can be performed according to the data transfer capability of the HDD 107.

With this configuration, the storage element can be selected according to the image data processing speed of the image forming apparatus, and the compression rate and the expansion rate differ depending on the image data (the data access speed to the memory depends on the type of data). However, it will be possible to adopt such a method. Compression rate,
If the expansion rate is variable, it may be possible to save the capacity of the storage device.

Next, an operation example of the memory controller 65 will be described. Here, an example is shown in which the HDD 107 cannot write / read data substantially in synchronization with the data transfer rate required at the time of image input / output.

<1> Image Input (Saving in Image Memory) The input data selector 101 selects image data to be written in the image memory (primary storage device 106) from a plurality of data. The image data selected by the input data selector 101 is supplied to the image synthesizing unit 102 and is synthesized with the data already stored in the image memory. The image data processed by the image combination 102 is compressed by the primary compression / expansion 103, and the compressed data is written in the primary storage device 106. The data written in the primary storage device 106 is further compressed by the secondary compression / expansion 105 if necessary, and then stored in the hard disk device (HDD) 107.

<2> Image Output (Reading from Image Memory) When outputting an image, the image data stored in the primary storage device 106 is read. If the image to be output is stored in the primary storage device 106, the primary compression /
The decompression 103 decompresses the image data in the primary storage device 106, and the decompressed data or the data after the image composition of the decompressed data and the input data is selected and output by the output data selector 104. .

The image synthesizing unit 102 synthesizes the data in the primary storage unit 106 and the input data (has a function of adjusting the phase of the image data) and selects the output destination of the synthesized data (image output, primary storage unit). Write back to 106, simultaneous output to both output destinations). If the image to be output is not stored in the primary storage device 106, the output target image data stored in the HDD 107 is expanded by the secondary compression / expansion 105, and the expanded data is primarily stored. After writing to the device 106, the above-described image output operation is performed.

The print unit 74, which is a device for generating print image data, is connected to the CPU bus and generates a page print character image, an arbitrary stamp image, and the like. The image image data generated by the printing unit 74 is used for the print synthesis 1 device 72,
It is possible to input an arbitrary image to the original image and the image from the memory by inputting it to the print synthesizing 2 device 73.

In particular, any stamp image is constructed so that the user can register it as needed. In the stamp image registration mode, the image from the scanner is registered in the above HDD, and when the user selects a necessary stamp image later, the stamp image data is read out from the HDD and sent to the print synthesizing devices 72, 73. It is sent and combined with the original image.

7 and 8 are diagrams showing an example of the area configuration of the hard disk. The hard disk is roughly divided into a management data area, a document image data area, and a stamp image data area. Position information of a defective block generated on the hard disk is recorded in the management data area, a plurality of original image data in the electronic sort mode is recorded in the original image data area, and user stamp image data registered by the user is recorded in the stamp image data area. It

As described above, the minimum allocation unit of the hard disk is usually a sector of 512 bytes, but in the present embodiment, the original image data is 64 KB / block and the stamp image data is 1 KB / block to allocate the storage area. . The reason why the block size is not fixed is to utilize the storage area effectively. The original image data area is 512 in 64 KB x 8192 (2000H) blocks.
The MB and stamp image data areas are 16 KB × 10 blocks and 160 KB are prepared.

FIGS. 7 and 8 show a state in which original image data and stamp image data are stored in the hard disk while avoiding defective blocks. A 1-bit flag is prepared for each block in the bad block management area, and when a bad block is found, the bit corresponding to the block number is set to manage the bad block location. It is necessary to frequently access the bad block management data during the copy operation. If the hard disk is accessed every time data is needed, copy productivity may decrease. Therefore, the defective block management data is read into the memory when the power of the device is turned on, and the copy in the memory is referred to during the normal copy operation. When registering a bad block, the management data on the memory is updated and simultaneously written to the hard disk to maintain the identity of the bad block management data.

Since the original image data is stored in the hard disk after being subjected to variable length compression, the original image data size changes according to the compression rate. Therefore, one document image data is divided into an indefinite number of blocks and recorded. Therefore, in order to manage the block number corresponding to each original, in the present embodiment, a directory table having a structure as shown in FIG. 9 and a block allocation table as shown in FIG. 10 are constructed on the memory.

The directory table has entries for the maximum number of originals, each of which corresponds to one original. Each entry holds the first block number of a plurality of block groups in which document image data is divided and recorded. The block allocation table has entries for the total number of blocks on the hard disk, each of which corresponds to one block. Each entry holds the next block number in which image data is recorded following that block. However, if the block is the last block forming one document image data, FFFFH is held as the end mark. Therefore, by referring to both the directory table and the block location table, it is possible to obtain a chain of block numbers connected in series corresponding to one original image.

Since only the information of the block having the defective sector is recorded on the hard disk and the directory table and the block allocation table showing whether each block is in use or not are constructed on the memory, for example, the image information is stored. In the case where the power is turned off and initialization is performed in this state, only the defective block information normally remains, and the image information is automatically unrecorded.

FIG. 11 is an operation flow for checking whether or not the hard disk has a defective sector. The presence of a defective sector is sequentially checked from block 0, and if a defective sector is found, the block number is registered in the defective block management area.

There are several possible methods for checking the defective sector. In this embodiment, a read command for all sectors included in a block is issued to the hard disk, and the end status returned from the hard disk determines whether or not the sector is a bad sector. Is going. Normally, the hard disk side automatically performs error correction and error retry processing, so even if a read error occurs, if error correction or retry recovers,
The main body side will not be able to obtain any information. Therefore, at the time of checking the defective sector, the error correction and error retry processing on the hard disk side are prohibited so that the defective sector can be surely detected.

According to the above embodiment, since the management method can be changed depending on the size of the image stored in the storage device, the storage area can be efficiently managed. Also, a small image does not unnecessarily occupy a storage area, and a large image does not increase the information in the management area.

The above-described embodiment is an example of a preferred embodiment of the present invention, but the present invention is not limited to this. For example, in the present embodiment, a defective sector is detected only by the read processing as described above. However, as a method for further increasing the defective sector detection rate, a procedure of confirming whether a predetermined data pattern can be written and read correctly can be considered.

[0044]

As is apparent from the above description, the image forming apparatus of the present invention stores the digitally converted image signal and manages the image signal by dividing it into predetermined minimum units. In this management, the minimum unit is selected according to the size of the image signal, and the storage is executed based on the selected minimum unit. Therefore, since the management method can be changed depending on the size of the image stored in the storage device, the storage area can be efficiently managed. Also, a small image does not unnecessarily occupy a storage area, and a large image does not increase the information in the management area.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a copying machine showing an embodiment of an image forming apparatus of the present invention.

FIG. 2 is a plan view of an operation unit shown in FIG.

FIG. 3 is a diagram showing an example of a display on a liquid crystal display of an operation unit.

FIG. 4 is a block diagram showing a configuration example of a control device.

FIG. 5 is a block diagram showing a configuration example of an image processing unit.

FIG. 6 is a block diagram showing a detailed configuration example of a memory controller and an image memory.

FIG. 7 is a diagram showing an example of the area configuration of a hard disk.

FIG. 8 is a diagram showing the configuration of a partial region of FIG. 7 in more detail.

FIG. 9 is a diagram showing a configuration example of a directory table.

FIG. 10 is a diagram showing a configuration example of a block allocation table.

FIG. 11 is a flowchart for explaining an operation procedure.

[Explanation of symbols]

 1 Automatic Document Feeding Device (ADF) 2 Document Platen 3 Feeding Roller 4 Feeding Belt 5 Ejecting Roller 6 Contact Glass 7 Original Set Detection 11, 12, 13 Paper Feeding Device 14 Vertical Conveying Unit 15 Photoreceptor 17 Fixing Unit 18 Ejecting Paper unit 30 Operation unit 31 Liquid crystal display 32 Numeric keypad 33 Clear / Stop key 34 Print key 35 Mode clear key 37 Function key 49 Image processing unit (IPU) 50 Reading unit 54 CCD image sensor 57 Writing unit 61 A / D converter 62 Shading correction Part 63 MTFγ correction 64 Selector 65 Memory controller 66 Image memory 67 I / O port 68 CPU 69 ROM 70 RAM 101 Input data selector 102 Image synthesis 103 Primary compression / expansion 104 Output data Selector 105 secondary compression / decompression 106 the primary storage device 107 a hard disk drive (HDD) 111 duplex paper feed unit 112 branch claw

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Norio Miyake 1-3-6 Nakamagome, Ota-ku, Tokyo Stock company Ricoh Co., Ltd. (72) Hiroyasu Sumita 1-3-6 Nakamagome, Ota-ku, Tokyo Shares Within Ricoh Company (72) Inventor Toshiya Tagawa 1-3-6 Nakamagome, Ota-ku, Tokyo Stock Company Ricoh (72) Inventor Moriyuki Koike 1-3-6 Nakamagome, Tokyo Stock Company Ricoh Company (72) Inventor Hiroshi Mori 1-3-6 Nakamagome, Tokyo, Ota-ku, Tokyo (72) Inventor Takahiko Uno 1-3-6 Nakamagome, Tokyo, Ota-ku, Tokyo (72) Invention Go Tsuyoshi Endo 1-3-6 Nakamagome, Ota-ku, Tokyo Within Ricoh Co., Ltd. (72) Inventor Hisashi Ishiguro 1-3-6 Nakamagome, Ota-ku, Tokyo Ricoh Co., Ltd. Inside

Claims (2)

[Claims] 1. A storage unit for storing a digitally converted image signal, and a management unit for managing the image signal by dividing the image signal into predetermined minimum units, wherein the management unit has a size of the image signal. According to this, the image forming apparatus is characterized in that the minimum unit is selected, and the storage in the storage unit is managed based on the selected minimum unit. 2. The image forming apparatus according to claim 1, wherein the storage unit is a hard disk device.