JPH11177770A - Image reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image reader which is capable of improving throughout at the time of one-side reading, without increasing cost caused by memory capacity. SOLUTION: It is basic that the memory capacity of an image memory for one side 36 is a reduced slightly to make an inexpensive product for a device body which is a base provided with only a one-side reading part 1 and that with respect to a user requiring both-side simultaneous reading a rear side reading part 2 is fixed later to provide a both-side simultaneous reading function and the memory capacity of an image memory for its rear side 41 is increased slightly to extend the memory capacity. In addition, at reading of one side in a state where the part 2 is a back matter, an image memory for the rear side of a larger memory capacity is used to reduce the possibility of generating intermittent operation due to a full memory to improve the throughput.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image scanner, a scanner section in a digital copying machine or a facsimile apparatus, and more particularly to an image reading apparatus capable of reading both sides.

[0002]

2. Description of the Related Art In general, when an image reading apparatus of this type is provided with a double-sided simultaneous reading apparatus, a DRA having the same memory capacity is provided exclusively for each of the front and rear reading surfaces of a document image.
An image memory such as M is provided.

In this case, the memory management is performed, for example, as shown in FIG.
As shown in the flowchart of (a), a SiBC (Scanner image Buffer Controller) that manages an image memory is used.
r) By setting the installed memory capacity,
While detecting the amount of image data during document reading, the reading operation of the scanner is performed intermittently so that the image data does not accumulate beyond the mounted memory capacity. In the case of the intermittent operation, taking the example of FIG. 8B as an example, if the mounted memory capacity is 2 Mbytes, and if the amount of image data being read is likely to exceed 2 Mbytes, the reading process is temporarily stopped (motor drive is stopped). However, since the stepping motor drive requires a through-down distance before stopping, it is completely 2M
Instead of stopping after reaching the byte, stop at the near full time with some margin), transfer the image data to the outside, and if there is room in the memory (that is, release of the near full state), temporarily By releasing the stop, the motor drive is resumed, and reading of the subsequent document image is resumed.

[0004]

In this case, if the memory capacity is large, the above-described intermittent operation is naturally unlikely to occur, and the throughput of the image reading apparatus is improved. In addition, at the time of double-sided reading, performance corresponding to the memory capacity is exhibited.

However, depending on the user, double-sided simultaneous reading is not always performed, and only single-sided reading is often required. For such a user, since only one side of the image memory is used, the back side image memory is wasted and the cost is high. Further, in order to avoid the intermittent operation as much as possible, the memory capacity may be increased as much as possible. However, as the memory capacity increases, the cost increases accordingly.

By the way, in a facsimile machine,
For example, as disclosed in Japanese Patent Application Laid-Open No. 9-205524, the same image memory is used for the front side and the back side. In the case of this method, the image memory is advantageous in terms of cost, but processing is performed in accordance with the compression efficiency of the front and back sides (the one having a lower scanning control speed), resulting in a decrease in throughput. I will.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image reading apparatus capable of improving the throughput at the time of single-sided reading without increasing the cost.

It is a further object of the present invention to provide an image reading apparatus which can further improve the throughput at the time of single-sided reading or double-sided reading.

[0009]

According to the first aspect of the present invention,
A double-sided simultaneous reading device including a single-sided reading unit and a backside reading unit that can be retrofitted, wherein the single-sided image memory corresponding to the single-sided reading unit and the memory capacity are set to be larger than those of the single-sided image memory; And a memory control means for performing a reading / storing process using the back-side image memory at the time of single-side reading in a state where the back-side reading unit is retrofitted.

Therefore, in the case of a base unit having only a single-sided reading unit, the memory capacity of the single-sided image memory is reduced to make it a low-priced product, and a backside reading unit is required for a user who needs simultaneous double-sided reading. Basically, it should have a double-sided simultaneous reading function by retrofitting, and at the same time, increase the memory capacity by increasing the memory capacity of the image memory for the back side. By using the image memory for the back surface having a larger capacity, the throughput is improved.

According to a second aspect of the present invention, there is provided a double-sided simultaneous reading device including a single-sided reading unit and a backside reading unit that can be retrofitted,
A single-sided image memory corresponding to the single-sided reading unit, and a back-side image memory that has a memory capacity set to be larger than the single-sided image memory and is attached later together with the back-side reading unit, wherein the back-side reading unit is attached later Memory control means for performing a reading and storing process using the one-side image memory and the back-side image memory at the time of one-side reading in a state in which the image is read.

Therefore, it is basically the same as the case of the first aspect of the present invention. In particular, the single-sided image memory and the back-side image memory which are both vacant at the time of one-side reading with the back-side reading unit attached are provided. Since both the image memory and the image memory are used, the memory capacity is sufficient and intermittent operation hardly occurs.
Throughput is further improved.

According to a third aspect of the present invention, there is provided a double-sided simultaneous reading device including a single-sided reading unit and a backside reading unit that can be attached later.
A single-sided image memory corresponding to the single-sided reading unit; and a back-side image memory whose memory capacity is set to be larger than that of the single-sided image memory and is attached together with the back-side reading unit. Memory control means for performing a reading storage process on each reading surface by using a memory capacity half of the total memory capacity of the memory and the image memory for the back surface.

Therefore, it is basically the same as the first and second aspects of the present invention. In particular, when reading both sides, a part of the back side image memory having a larger memory capacity is used for one side. By using the same memory capacity for supplementing the image memory, the throughput is improved as compared with the case of using only the single-sided image memory.

[0015]

FIG. 1 shows a first embodiment of the present invention.
A description will be given with reference to FIG. The image reading apparatus according to the present embodiment is applied to an image reading system 100 as shown in FIG. The image reading system 100 has a configuration in which an image scanner 101 is connected to a host computer 102.

The image scanner 101 exemplified here
Basically, as shown in FIG. 3, there is provided a double-sided simultaneous reading device 3 including a single-sided reading unit 1 capable of selecting a document fixing mode and a document conveying mode, and a backside reading unit 2 that can be retrofitted. It has been. Therefore, a product that includes only the single-sided reading unit 1 is provided to a user who does not need the double-sided simultaneous reading function.

First, the configuration of the single-sided reading section 1 will be described. A contact glass 4 on which a document to be read is placed has a first traveling body 7 on which a reflecting mirror 5 and an illumination lamp 6 are mounted in a position facing the contact glass 4 from below. A is movably arranged. Two reflection mirrors 8 are provided on the reflection optical path of the first traveling body 7.
A second traveling body 9 whose optical path is turned back by the movable member 9 is disposed so as to be movable in the sub-scanning direction, and a reflected light path of the second traveling body 9 is provided via an imaging lens 10 with a CCD (Charge Couple).
d Device) 11 is located.

A traveling body motor 12 using a stepping motor is connected to the first traveling body 7 and the second traveling body 9 by a pulley, a wire, or the like, and is movable in the same sub-scanning direction at a speed of 2: 1. It has been. By moving the two traveling bodies 7 and 9 in this manner, the contact glass 4 is moved.
1 is scanned by the CCD 11 in the sub-scanning direction, and the single-sided reading unit 1 is configured here.

The scanning of the original to be read by the single-sided reading unit 1 is executed under the setting of the book mode which is the original fixed mode.
In A01, an ADF mode, which is a document transport mode, is set as a switchable operation mode in addition to the book mode described above. Under the setting of the ADF mode, as shown by a broken line at the right end in the figure, the AD is set in a state where the two traveling bodies 7 and 9 are arranged at the stop reading position B which is the home position.
An F (Automatic Document Feeder) 13 conveys and sequentially scans the read document in the sub-scanning direction and reads and scans image data.

The ADF 13 includes a document tray 14, a pickup roller 15, a pair of registration rollers 16, a transport drum 17, a pair of transport rollers 18, a pair of discharge rollers 19, and the like. B in the sub-scanning direction so as to sequentially pass through
0 is discharged. The paper discharge tray 20 is formed on the upper surface of a document pressure plate 21, and the document pressure plate 21 is provided on the contact glass 4 so as to be openable and closable. A paper feed motor composed of a stepping motor is connected to the pickup roller 15, the registration roller 16, the transport drum 17, and the transport roller 18 of the ADF 13 by a gear train or the like.
In the ADF 13, an endorcer unit 23 and an endor platen 24 are disposed between the transport roller 18 and the paper discharge roller 19. The endorser unit 23 includes a printing unit including a mark of alphabet letters and numbers impregnated with ink, and a press solenoid 25 (FIG. 4) that presses the printing unit to the endorser platen 24 side.
The read original is stopped on the endorser unit 23, and is fixed in the pressing direction by an endorser platen 24.
By applying pressure to the printing section in No. 3, alphabet letters and numbers can be printed on the document surface.

Next, the back surface reading section 2 will be described. The back side reading unit 2 is an optional member that can be retrofitted,
A contact type image sensor 26 and a white roller 27 are provided afterwards at a reading position C set downstream of the transport drum 17 in the ADF 13 in the document transport direction and in front of the transport roller 18. Here, the contact type image sensor 26 is for reading a document surface (back surface) opposite to the CCD 11 side, and is disposed downward above the transport path, and a lamp for illuminating the document surface or a 1: 1 magnification is used. This is a unit-size photoelectric conversion element formed by integrating an imaging lens array and a sensor array. The white roller 27 located on the opposite side of the conveyance path is also used as a white member for shading correction at the time of reading by the contact type image sensor 26.

In addition, a unit substrate constituting an electrical system described below is incorporated below the inside of the image scanner 101. Therefore, such an image scanner 101
The block structure of the electrical system will be described below together with its operation with reference to FIGS.

First, SBU (Sensor Board Unit) 3
The reflected light of the read original that has entered the upper CCD 11 is converted into analog image data having a voltage value corresponding to the light intensity in the CCD 11, and is divided into odd bits and even bits and output. . This analog signal is SBU3
After the dark potential portion is removed by an analog processing circuit (not shown) on 1, odd bits and even bits are combined, the gain is adjusted to a predetermined amplitude, and then A / D (Analog / Di)
gital) is input to a converter (not shown) and digitized.

The digitized image data is an SCU
After the shading correction, the gamma correction, the MTF correction, and the like are performed by the NIPU 33 on the (Scanner Control Unit) 32, the binarization processing is performed. The binarized image data is output as a video signal together with a page synchronization signal, a line synchronization signal, and an image clock.

The video signal output from the NIPU 33 is supplied to an optional IPU 35 via a connector 34.
Is input to The video signal input to the option IPU 35 is subjected to predetermined image processing in the option IPU 35, and is input to the SCU 32 again. The video signal input again to the SCU 32 is input to a selector (not shown). The other input of this selector is NIPU3
The video signal is output from the video signal 3 and the option IPU 35 can select whether or not to perform image processing. A video signal output from this selector is a DRAM (Dynamic Random Access Memory) which is a single-sided image memory.
ry) is input to the SiBC 37 for managing the
36 stores the image data. The image data stored in the DRAM 36 is a SCSI (Small Computer Sy).
The data is transferred to the host computer 102 via the stems interface controller 38.

On the other hand, the analog image signal photoelectrically converted by the contact type image sensor 26 is
It is converted into a digital image signal on the SBU 39. The digitized image signal is subjected to shading correction on the RSBU 39, and then the RCU (Riverse side) in the main body.
Control Unit 40). The RCU 40 includes a DRAM 41 serving as a back side image memory,
The configuration includes a SiBC 42 and a NIPU 43 for controlling the AM 41. The image data is temporarily stored in the DRAM 41 and then transferred to the SCU 32. RCU40 to SCU
Image data transferred to SCU32 and SiBC on SCU32
The image data can be switched with the image data output from the image data 37, and any image data is selected and transferred to the SCSI controller 38. Here, the memory capacity of the DRAMs 36 and 41 will be described. The memory capacity of the DRAM 41 is set larger. For example, as shown in FIG. 2, the memory capacity of the DRAM 36 is 2 Mbytes, whereas the memory capacity of the DRAM 41 is 8 Mbytes.

On the SCU 32, a CPU is provided.
44, a ROM 45, and a RAM 46 are mounted.
U44 operates to control the SCSI controller 38 to communicate with the host computer 102. CP
U44 also controls the operation timing by controlling the drive pulses of the traveling body motor 12, the paper feed motor, the transport motor, and the like. ADU (ADF Driving Uni)
t) 47 has a function of relaying power supply of electrical components used for the ADF 13.

An operation panel 48 having a keyboard and a display is provided on the outer surface of the apparatus of the image scanner 101.
4 is connected. A start switch and an abort switch are provided on the operation panel 48. When these switches are pressed, the CPU is connected to the CPU through an input port.
44 detects that the corresponding switch is turned on.

As shown in FIG. 5, the ADF 13 is provided with various sensors 49 to 52 at respective optimal positions with respect to a document transport path 53 formed around the transport drum 17. Sensors 49 to 52 are also CPU4
4 is connected. A document presence / absence sensor 49 is provided on the document tray 14 and determines the presence or absence of a read document. Similarly, the conveyance sensor 50 detects the start of conveyance of the read document. The reading position sensor 51 detects that the conveyed document has reached the reading position,
2 detects that the scanned original has been discharged.

In such a configuration, the memory management
By setting the memory capacities of the DRAMs 36 and 41 mounted on the SiBCs 37 and 42, the reading operation of the image scanner 101 is performed so that the amount of image data during document reading is detected and the image data is not accumulated beyond the mounted memory capacity. Perform while performing intermittent operation. Here, as a set of the memory capacity, as shown in FIG.
0, that is, if the back side reading unit 2 is not mounted,
The memory capacity of the BC 37 is set to 2 Mbytes which is the memory capacity of the DRAM 36, and the memory path is a single-sided image memory DR as shown by a solid line in FIG.
Set to AM37. As a result, the reading and storing process is performed by using the DRAM 37 during the one-side reading. That is, in this case, the DRAM 37 is used as an image memory.
It is a low-priced product with only
The memory control uses M37.

On the other hand, in the case of a device in which the RCU 40, and hence the back side reading unit 2, is retrofitted, the memory capacity of the DRAM 41 is 8M as the memory capacity of the SiBC 37.
A byte is set, and the memory path is a DRAM 4 which is an image memory for the back side as shown by a dashed line in FIG.
Set to 1. The switching of the memory path in the above case is performed by the port operation of the CPU 44. As a result, the reading / storing process can be performed assuming that the DRAM 41 having the larger memory capacity is mounted as the image memory, even when the single-sided reading unit 1 performs the single-sided reading.

Accordingly, in the intermittent operation in this case, as shown in FIG. 1B, when the amount of image data being read by the one-sided reading unit 1 is likely to exceed 8 Mbytes, the reading process is temporarily stopped. When the image data is transferred to the outside and a margin is made in the memory (that is, the near full state is released), the motor drive is resumed by releasing the pause, and the reading of the subsequent document image is resumed. Become. A series of processing shown in FIGS. 1A and 1B is executed as a function of the memory control unit. That is, the control itself of the intermittent operation is the same as that shown in FIG. 8B, but in the case of the present embodiment, it is retrofitted and has a large memory capacity (8 Mbyt).
e) Since the DRAM 41 is used, there is little possibility that the memory becomes near full, and intermittent operation hardly occurs.
The throughput at the time of one-sided reading is good.

A second embodiment of the present invention will be described with reference to FIG. The same parts as those described in the above embodiment are denoted by the same reference numerals, and description thereof is omitted (the same applies to the following embodiments). The memory management of the present embodiment
By setting the memory capacities of the DRAMs 36, 41 mounted on the iBCs 37, 42, the reading operation of the image scanner 101 is performed while detecting the amount of image data during document reading so that the image data does not accumulate beyond the mounted memory capacity. Perform while performing intermittent operation. Here, as a set of the memory capacity, as shown in FIG. 6A, regardless of whether the RCU 40 and, therefore, the back surface reading unit 2 is mounted,
The memory capacity of the SiBC 37 is set to 2 Mbytes which is the memory capacity of the DRAM 36, and the memory path is set to the DRAM 36 which is a one-sided image memory as shown by a solid line in FIG. That is, it is the same as the case of the conventional control method shown in FIG.

As the actual intermittent operation, the RCU
40, and therefore, if the back side reading unit 2 is not mounted, the operation is performed in the same manner as in the related art.
Is a retrofitted device, the control is performed as shown in FIG. If the amount of image data being read by the single-sided reading unit 1 has reached 2 Mbytes, the memory capacity of the unused DRAM 41 of 8 Mbytes is set to SiB.
While setting a new memory capacity of C42,
The memory path is switched to the DRAM 41 side. This allows
Further, the memory capacity of 8 Mbytes can be used for the reading and storing process by the single-sided reading unit 1. Even in such a state, if the amount of image data being read by the single-sided reading unit 1 is likely to exceed 8 Mbytes, the reading process is temporarily stopped and the image data is transferred to the outside, so that there is a margin inside the memory (that is, When the near full state is released), the motor drive is resumed by releasing the temporary stop, and reading of the subsequent document image is resumed. A series of processes shown in FIGS. 6A and 6B are executed as a function of the memory control unit. That is, according to the present embodiment, the DRA which is the original one-sided image memory is used.
Since the M36 and the DRAM 41 serving as the back-side image memory are combined and used for the one-sided reading process by the one-sided reading unit 1, there is almost no possibility that the memory becomes nearly full, and intermittent operation hardly occurs. Therefore, the throughput at the time of single-sided reading is further improved.

A third embodiment of the present invention will be described with reference to FIG. The memory management according to the present embodiment relates to control during simultaneous double-sided reading. By setting the memory capacities of the DRAMs 36 and 41 mounted on the SiBCs 37 and 42, while detecting the amount of image data during document reading,
The reading operation of the image scanner 101 is performed intermittently so that the image data does not accumulate beyond the mounted memory capacity. Here, as the set of memory capacity, RCU
40, and therefore, it is premised that the back side reading unit 2 is mounted, but the memory capacity of the SiBC 37 is as shown in FIG.
As shown in FIG. 2A, the memory capacity of the corresponding DRAM 36 is set to 2 Mbytes, and the memory path is a single-sided image memory D as shown by a solid line in FIG.
Set in the RAM 36. That is, it is the same as the case of the conventional control method shown in FIG.

FIG. 7 shows the actual intermittent operation.
Control is performed as shown in FIG. When the amount of image data being read by the single-sided reading unit 1 reaches 2 Mbytes, a part of the memory capacity of the DRAM 41 used for the back side is used. That is, the memory capacity of the SiBC 42 is 3 Mby.
te (total memory capacity of both 10 Mbyte / 2-memory capacity for one side 2 Mbyte) and set the memory path to DRAM 41
Switch to. As a result, the memory capacity of 3 Mbytes can be further used for the reading and storing process by the single-sided reading unit 1. Even in such a state, if the amount of image data being read by the single-sided reading unit 1 is likely to exceed 3 Mbytes, the reading process is temporarily stopped and the image data is transferred to the outside, so that there is a margin inside the memory (that is, When the near full state is released), the motor drive is resumed by releasing the temporary stop, and reading of the subsequent document image is resumed. FIG.
A series of processing shown in (a) and (b) is executed as a function of the memory control means. Although not particularly shown, the DRAM
The remaining memory capacity of 41 Mbyte of 41 is used for reading and storing processing by the back surface reading unit 2. That is, according to the present embodiment, with respect to the image storage processing by the single-sided reading unit 1 at the time of double-sided reading, the DRAM which has been added later and has a larger memory capacity is used.
By using a part of 41 as a supplement for the DRAM 36 to make the memory capacity equally on the front and back, the possibility of memory near full is reduced as compared with the case of only the DRAM 36, and intermittent operation is less likely to occur. Therefore, the throughput at the time of one-sided reading is improved.

[0037]

According to the first aspect of the present invention, there is provided a double-sided simultaneous reading device including a single-sided reading unit and a backside reading unit that can be retrofitted, and a single-sided image memory and a single-sided image memory corresponding to the single-sided reading unit. A back-side image memory that has a larger memory capacity than the memory and is attached together with the back-side reading unit, and performs a reading and storing process using the back-side image memory when performing single-sided reading with the back-side reading unit attached. By providing a memory control unit that makes it possible to provide a low-priced product with only a single-sided reading unit and a smaller memory capacity for the single-sided image memory in the base unit, Basically, the backside reading unit is retrofitted to provide both-sided simultaneous reading function and increase the memory capacity of the backside image memory by increasing it. And, and, since the time of reading one side and to use a back surface image memory towards the memory capacity large, reducing the possibility of occurrence of an intermittent operation of the memory full, it is possible to improve the throughput.

According to the second aspect of the present invention, there is provided a double-sided simultaneous reading device including a single-sided reading unit and a backside reading unit that can be retrofitted, and a single-sided image memory corresponding to the single-sided reading unit and a single-sided image memory. Also includes a backside image memory that has a large memory capacity and is attached later together with the backside reading unit. When the backside reading unit is retrofitted, the single-sided image memory and the backside image memory are used for reading and storing. By providing a memory control means for performing the processing, it is basically the same as the case of the invention according to claim 1, but in particular, the single-sided image memory and the back-side image memory which are both vacant at the time of single-sided reading. Since both are used, the capacity of the memory is sufficient and the intermittent operation due to the memory full hardly occurs, and the throughput can be further improved.

According to the third aspect of the present invention, there is provided a double-sided simultaneous reading device including a single-sided reading section and a backside reading section that can be retrofitted, and a single-sided image memory corresponding to the single-sided reading section and a single-sided image memory. Also has a backside image memory that has a large memory capacity and is attached later together with the backside reading unit, and uses half of the total memory capacity of the single-sided image memory and the backside image memory when reading both sides. By providing a memory control means for performing a reading and storing process for each reading surface, it is basically the same as the case of the first and second aspects of the present invention. The larger part of the back side image memory is used for supplementing the one sided image memory so as to have an equal memory capacity. Reduce the possibility of occurrence of an intermittent operation by, it is possible to improve the throughput.

[Brief description of the drawings]

FIG. 1 is a flowchart showing memory management control according to a first embodiment of the present invention.

FIG. 2 is a schematic block diagram illustrating an image reading system.

FIG. 3 is a schematic front view illustrating a configuration example of an image reading apparatus.

FIG. 4 is a block diagram showing a configuration example of the electrical system.

FIG. 5 is a schematic front view showing an outline of an ADF structure.

FIG. 6 is a flowchart illustrating memory management control according to the second embodiment of this invention.

FIG. 7 is a flowchart illustrating a memory management control according to the third embodiment of this invention.

FIG. 8 is a flowchart showing conventional memory management control.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 single-sided reading unit 2 back-side reading unit 3 double-sided simultaneous reading device 36 single-sided image memory 41 back-side image memory

Claims (3)

[Claims] 1. A double-sided simultaneous reading device including a single-sided reading unit and a backside reading unit that can be retrofitted, wherein a single-sided image memory corresponding to the single-sided reading unit and a memory capacity are set larger than the single-sided image memory. And a memory control means for performing a reading and storing process using the back-side image memory at the time of single-side reading in a state where the back-side reading unit is retrofitted. Image reading device. 2. A double-sided simultaneous reading device comprising a single-sided reading unit and a backside reading unit that can be retrofitted, wherein a single-sided image memory corresponding to the single-sided reading unit and a memory capacity are set larger than the single-sided image memory. A back-side image memory that is attached later together with the back-side reading unit, and performs a reading and storing process using the one-side image memory and the back-side image memory at the time of one-side reading with the back-side reading unit attached. An image reading device comprising a memory control unit for causing the image reading device to read the image data. 3. A double-sided simultaneous reading device including a single-sided reading unit and a backside reading unit that can be retrofitted, wherein a single-sided image memory corresponding to the single-sided reading unit and a memory capacity are set larger than the single-sided image memory. A back-side image memory that is attached later together with the back-side reading unit. When reading both sides, each of the reading surfaces is used by using a half of the total memory capacity of the single-sided image memory and the back-side image memory. An image reading apparatus comprising a memory control means for performing a reading and storing process.