JP2022156046A - Image forming apparatus - Google Patents

Abstract

To provide an image forming apparatus that dynamically controls the timing to start secondary paper feeding.SOLUTION: A calculation unit 12 calculates the number of preferentially conveyed bands in output sheets 23 based on the distance from a registration roller 70 to a transfer roller 36, the speed of an engine unit 60 conveying the output sheets 23, the speed of an image reading unit 80 reading a document, the size of the document, and processing time required for an image editing unit 11 for editing processing. An engine control unit 13 controls the engine unit 60 so that the registration roller 70 conveys, to the transfer roller 36, the output sheets 23 in a number equal to the number of preferentially conveyed bands.SELECTED DRAWING: Figure 1

Description

The present invention relates to an image forming apparatus.

Japanese Unexamined Patent Application Publication No. 2002-200002 discloses an image forming apparatus capable of increasing the first copy speed in copying involving image editing such as enlarging, reducing, and rotating a document. The image forming apparatus described in Japanese Patent Application Laid-Open No. 2002-200001 starts primary paper feeding to reach the registration rollers from the paper feed cassette during the period from the start of document reading to the end of editing processing of the read image. do. Further, the image forming apparatus described in Japanese Patent Application Laid-Open No. 2002-200002 starts secondary paper feeding for ejecting the output paper from the registration rollers through the transfer position after finishing the editing process of the read image.

JP-A-2007-47509

The image forming apparatus described in Japanese Patent Application Laid-Open No. 2002-200002 does not start secondary paper feeding until all the read image data have been edited. However, since the image data read by the image reading unit is edited in units of bands divided into strips, the image forming apparatus theoretically transfers the output paper portion corresponding to the band for which the editing process is completed to the registration roller. can be transported from the substrate to the transfer position.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image forming apparatus that dynamically controls the timing of starting secondary sheet feeding.

An image forming apparatus according to the present invention includes an image reading section, an image editing section, an engine section, a calculating section, and an engine control section. The document reading unit reads a document and generates image data. The image editing unit edits the image data in band units. The engine unit drives the registration rollers arranged in the transport path to transport the output paper to the transfer rollers. The calculation unit calculates the distance from the registration roller to the transfer roller, the speed at which the engine unit conveys the output paper, the speed at which the image reading unit reads the document, the size of the document, and the image editing unit. Based on the processing time required for the editing process, the number of preceding transport bands on the output paper is calculated. The engine control section controls the engine section so that the registration roller conveys the output paper to the transfer roller by the number of preceding conveyance bands.

According to the present invention, it is possible to provide an image forming apparatus that dynamically controls the timing of starting secondary sheet feeding.

1 is a block diagram showing a configuration example of an image forming apparatus according to Embodiment 1; FIG. 1 is a diagram illustrating a structural example of an image forming apparatus according to Embodiment 1; FIG. 4 is a timing chart showing an operation example of the image forming apparatus according to Embodiment 1;

An embodiment of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

<Embodiment 1>
An image forming apparatus 1 according to the first embodiment will be described with reference to FIGS. 1 to 3. FIG. FIG. 1 is a block diagram showing a configuration example of an image forming apparatus 1 according to the first embodiment. FIG. 2 is a diagram showing a structural example of the image forming apparatus 1 according to the first embodiment.

The image forming apparatus 1 includes an operation section 2 , a display section 3 , a control section 10 , a feeding section 20 , an image forming section 30 , a fixing section 40 , a discharge section 50 , an engine section 60 and an image reading section 80 .

The operation unit 2 is a touch panel, physical buttons, or the like that accepts user operations. For example, the operation unit 2 accepts an operation for designating the size and resolution of a document to be copied, the type of output paper, and the like. The operation unit 2 also accepts a copy start instruction. The operation unit 2 outputs the content of the received operation to the control unit 10 .

The display unit 3 is a display or the like that displays a screen received from the control unit 10 . The touch panel of the operation unit 2 may be attached to the display surface of the display unit 3 . For example, the display unit 3 displays a screen on which buttons for changing the size and resolution of the document to be copied, the paper type of the output paper, etc., a copy start button, etc. are arranged.

The control unit 10 controls each element of the image forming apparatus 1 . The control unit 10 has, for example, a processor such as a CPU (Central Processing Unit), and memories such as ROM (Read Only Memory) and RAM (Random Access Memory). The control unit 10 operates the operation unit 2, the display unit 3, the feeding unit 20, the image forming unit 30, the fixing unit 40, the discharging unit 50, and the engine unit 60 by executing a computer program pre-stored in the memory by the processor. , and the operation of the image reading unit 80 .

The control unit 10 also controls operations of the image editing unit 11, the calculation unit 12, and the engine control unit 13 by the processor executing a computer program stored in the memory. Specifically, the control unit 10 includes an image editing unit 11 , a calculation unit 12 and an engine control unit 13 . Details of the image editing unit 11, the calculating unit 12, and the engine control unit 13 will be described later.

The feeding section 20 has a feeding cassette 21 and a feeding roller group 22 . The feed cassette 21 can accommodate a plurality of output sheets 23 . The output paper 23 is plain paper, copy paper, recycled paper, thin paper, thick paper, glossy paper, OHP (Overhead Projector) paper, or the like.

The feeding roller group 22 conveys the output paper 23 accommodated in the feeding cassette 21 one by one to the registration rollers 70 . Note that the feeding unit 20 may have a manual feed tray 24 . The registration rollers 70 convey the output paper 23 to the transfer rollers 36 of the image forming section 30 .

The image forming section 30 uses toner to form an image on the output paper 23 conveyed by the registration rollers 70 . The image forming section 30 includes a toner supply device 31 , an exposure device 32 , a photosensitive drum 33 , a developing roller 34 , an intermediate transfer belt 35 and a transfer roller 36 .

The toner replenishing device 31 replenishes the toner in the toner cartridge Ca to the developing roller 34 . In this example, there are four types of toner cartridges Ca: black, cyan, magenta, and yellow.

The exposure device 32 irradiates and exposes the photosensitive drum 33 with a laser beam to form an electrostatic latent image on the exposed portion. The developing roller 34 supplies toner to the photosensitive drum 33 to develop the electrostatic latent image. As a result, an image is formed on the photosensitive drum 33 .

The intermediate transfer belt 35 transfers the image formed on the photosensitive drum 33 . The registration rollers 70 convey the output paper 23 to the transfer rollers 36 . A transfer roller 36 transfers the image transferred to the intermediate transfer belt 35 to the output paper 23 . The sheet with the transferred image is conveyed to the fixing section 40 .

The fixing section 40 has a heating roller 41 and a pressure roller 42 . The image transferred to the output paper 23 is fixed on the output paper 23 by heating and pressing the output paper 23 with the heating roller 41 and the pressure roller 42 . The discharge unit 50 discharges the sheet on which the image is fixed to the outside of the apparatus main body.

The engine section 60 is a motor that rotates the registration rollers 70 . Although FIG. 2 shows only the engine section 60 that drives the registration rollers 70, the engine section ( not shown) are provided. Each engine section including the engine section 60 is controlled by the engine control section 13 .

The image reading unit 80 has contact glass, a light source, an image sensor, and a movement mechanism (not shown). The contact glass has a set surface on which a document is set. The light source irradiates the document set on the setting surface with light. The image sensor has a plurality of photoelectric conversion elements arranged in the main scanning direction. The image sensor reads the document line by line by receiving reflected light reflected from the document, and outputs the read image data to the control unit 10 . The moving mechanism moves the read line read by the image sensor in the sub-scanning direction by moving the light source in the sub-scanning direction.

The image editing unit 11 edits the image data read by the image reading unit 80 in band units. Editing processing includes rotation processing, screen processing, and the like. The image editing unit 11 outputs the image data after image editing to the exposure device 32 .

Next, conveyance of the output paper 23 will be described. The output paper 23 is conveyed from the feeding section 20 to the discharging section 50 along the conveying path. When the image forming apparatus 1 performs copy processing, the output paper 23 is primarily fed from the feed cassette 21 until it reaches the registration roller 70 , is transferred from the registration roller 70 by the transfer roller 36 , and is discharged to the discharge section 50 . It goes through the secondary paper feeding process until it is finished.

The control unit 10 instructs the engine control unit 13 to start primary paper feeding at the timing when the image reading unit 80 starts the document reading process. The engine control unit 13 drives the feed roller group 22 by controlling the engine unit (not shown) to convey the output paper 23 from the feed cassette 21 to the registration rollers 70 .

The image forming apparatus described in Japanese Patent Application Laid-Open No. 2002-200003 starts secondary paper feeding when editing processing of all the image data is completed. was sending out.

On the other hand, the image editing unit 11 according to the first embodiment performs document reading processing and image data editing processing in band units. Therefore, the image forming apparatus 1 according to the first embodiment can start the secondary paper feeding ahead of schedule by the number of preceding transport bands calculated by the calculating unit 12 without waiting for the completion of the editing process of all the image data.

The calculation unit 12 calculates the distance from the registration roller 70 to the transfer roller 36, the speed at which the engine unit 60 conveys the output paper 23, the speed at which the image reading unit 80 reads the document, the size of the document, and the image editing unit 11 performs the editing process. The number of preceding transport bands on the output paper 23 is calculated based on the processing time required for the processing.

The engine control unit 13 controls the engine unit 60 based on the calculation result of the calculation unit 12 so that the registration rollers 70 convey the output paper 23 to the transfer roller 36 by the number of preceding conveyance bands.

The number of preceding transport bands is calculated during the primary paper feeding of the first copy, that is, from the time when the operation unit 2 receives a copy start instruction from the user to the time when the output paper 23 reaches the registration rollers 70. .

For example, the calculator 12 obtains the number of unprocessed bands and the total number of bands by calculating the following formulas, and uses the number of unprocessed bands and the total number of bands to obtain the number of preceding transport bands. The number of unprocessed bands corresponds to the number of bands that can be edited by the image editing unit 11 while the output paper 23 is conveyed from the registration rollers 70 to the transfer rollers 36 .

Number of unprocessed bands = (L1/V1)/(L2/V2+T1)
Total number of bands = (L3/L2)
Number of preceding transport bands = (Total number of bands - Number of unprocessed bands)

L1: Distance from registration roller 70 to transfer roller 36 L2: Length of one band L3: Document size V1: Speed V2 at which engine unit 60 conveys output paper 23: Speed T1 at which image reading unit 80 reads the document: Processing time per band required for editing processing by the image editing unit 11

A distance L<b>1 from the registration roller 70 to the transfer roller 36 and a length L<b>2 of one band are values uniquely defined for each model of the image forming apparatus 1 , and are set in the calculation unit 12 in advance.

The document size L3 is the length of the document in the sub-scanning direction. The calculation unit 12 acquires the size L3 from the image reading unit 80 or the operation unit 2 .

The speed V1 at which the engine section 60 conveys the output paper 23 is the process linear speed. The calculation unit 12 acquires from the engine control unit 13 the actual speed V1 at which the output paper 23 is conveyed from the registration rollers 70 to the transfer rollers 36 . Note that the speed V1 changes according to the weight of the output paper 23 and the like. Therefore, the calculation unit 12 may acquire the paper type detection result from a media sensor or the like that detects the paper type of the output paper 23, and correct the speed V1 based on the acquired paper type detection result or the like.

The speed V2 at which the image reading unit 80 reads the document is the reading linear speed. The speed V2 changes according to the resolution of document reading and the like. Therefore, the calculation unit 12 acquires the actual speed V2 from the control unit 10 that controls the movement mechanism of the image reading unit 80 or the operation unit 2 .

A processing time T<b>1 per band that the image editing unit 11 requires for editing processing is set in advance for the calculating unit 12 . Alternatively, the calculation unit 12 may estimate the processing time T1 that is closer to the actual one based on the details of the operation instructed by the user to the operation unit 2 .

Here, an example of calculating the number of preceding transport bands will be shown.
Distance L1 from registration roller 70 to transfer roller 36
: 100mm
Number of lines in one band: 128 lines Resolution of image reading unit 80: 600 dpi
1 band length L2: 600/128 = 5.42 mm
Document size L3: 215.9 mm
Velocity V1 at which the engine unit 60 conveys the output paper 23
: 250 mm/sec speed V2 at which the image reading unit 80 reads the document
: 300 mm/sec Processing time T1 per band required for editing processing by the image editing unit 11
: 10 milliseconds

Time required for transport from registration roller 70 to transfer roller 36 = L1/V1
= 100/250 = 0.4 seconds = 400 milliseconds

Reading time per band + Processing time T1 per band
=L2/V2+T1
= 5.42/300 + 10 = 0.01807 seconds + 10 milliseconds = 28.07 milliseconds

Number of unprocessed bands = (L1/V1)/(L2/V2+T1)
= 400/28.07 = 14.25 milliseconds ≈ 15 bands

The units of (L1/V1) and (L2/V2+T1) are time, but since (L2/V2+T1) is the time per band, the unit of (L1/V1)/(L2/V2+T1) is become a band.

Total number of bands = (L3/L2)
= 215.9/5.42 = 39.8 ms ≈ 40 bands

Number of preceding transport bands = (Total number of bands - Number of unprocessed bands)
= 40-15 = 25 bands

FIG. 3 is a timing chart showing an operation example of the image forming apparatus 1 according to the first embodiment. "Copy start instruction" in FIG. 3 indicates the timing when the operation unit 2 receives the copy start instruction from the user. Upon receiving the copy start instruction, the operation unit 2 outputs the copy start instruction to the control unit 10 .

Upon receiving a copy start instruction from the operation unit 2, the control unit 10 instructs the image reading unit 80 to start reading processing. The image reading unit 80 starts the document reading process according to an instruction from the control unit 10 and outputs the read image data to the image editing unit 11 . Image editing unit 11 edits the image data received from image reading unit 80 band by band, and outputs the edited image data to image forming unit 30 .

Further, upon receiving a copy start instruction from the operation unit 2, the control unit 10 instructs the engine control unit 13 to start primary paper feeding. The engine control unit 13 drives the feed roller group 22 by controlling an engine unit (not shown) to convey the output paper 23 from the feed cassette 21 to the registration rollers 70 .

Further, when receiving a copy start instruction from the operation unit 2, the control unit 10 instructs the calculation unit 12 to perform processing for calculating the number of preceding transport bands. The calculator 12 calculates the number of preceding transport bands according to the instruction from the controller 10 . The calculator 12 outputs the calculated number of preceding transport bands to the engine controller 13 .

The engine control unit 13 receives the preceding transport band number from the calculation unit 12 during control of primary paper feeding. After completing the primary paper feeding, the engine control unit 13 starts secondary paper feeding. That is, the engine control section 13 drives the registration rollers 70 by controlling the engine section 60 to convey the output paper 23 from the registration rollers 70 to the transfer rollers 36 . Further, the engine control section 13 controls the engine section of the transfer roller 36 in accordance with the start timing of the secondary paper feeding, thereby starting the image forming process of the image forming section 30 .

After the registration rollers 70 have conveyed the output paper 23 for the preceding conveyance band number, the engine control unit 13 also causes the output paper 23 for the unprocessed band number to be conveyed to the transfer roller 36 .

In the example of FIG. 3 , primary paper feeding is completed during the reading process of the image forming section 30 and the editing process of the image editing section 11 . Therefore, after the secondary paper feeding is started, the reading process of the image forming section 30 and the editing process of the image editing section 11 are performed in parallel with the conveyance of the output paper 23 from the registration roller 70 to the transfer roller 36 .

As described above with reference to FIGS. 1 to 3, the image forming apparatus 1 includes the image reading section 80, the image editing section 11, the engine section 60, the calculating sections 12, and . The image reading unit 80 reads a document and generates image data. The image editing unit 11 edits image data in units of bands. The engine unit 60 drives the registration rollers 70 arranged on the transport path to transport the output paper 23 to the transfer rollers 36 . The calculation unit 12 calculates the distance from the registration roller 70 to the transfer roller 36, the speed at which the engine unit 60 conveys the output paper 23, the speed at which the image reading unit 80 reads the document, the size of the document, and the image editing unit 11 performs the editing process. The number of preceding transport bands on the output paper 23 is calculated based on the processing time required for the processing. The engine control section 13 controls the engine section 60 so that the registration rollers 70 convey the output paper 23 to the transfer roller 36 by the number of preceding conveyance bands. As described above, the image forming apparatus 1 starts the secondary paper feeding earlier by the number of preceding transport bands, so that the timing of starting the secondary paper feeding can be dynamically controlled. As a result, the image forming apparatus 1 can start secondary paper feeding before the reading process of the image reading section 80 and the editing process of the image editing section 11 are completed, so that the performance of the first copy can be expected to be improved.

In addition, in order to facilitate understanding, the drawings schematically show mainly the respective constituent elements. Therefore, the thickness, length, etc. of each illustrated component are different from the actual ones for convenience of drawing.

The present invention can be applied to various image forming apparatuses, whether for home use or business use.

1 image forming apparatus 2 operation unit 3 display unit 10 control unit 11 image editing unit 12 calculation unit 13 engine control unit 20 feeding unit 21 feeding cassette 22 feeding roller group 23 output paper 24 manual feed tray 30 image forming unit 31 toner supply Device 32 Exposure device 33 Photoreceptor drum 34 Development roller 35 Intermediate transfer belt 36 Transfer roller 40 Fixing unit 41 Heating roller 42 Pressure roller 50 Discharge unit 60 Engine unit 70 Registration roller 80 Image reading unit Ca Toner cartridge

Claims (2)

an image reading unit that reads an original and generates image data;
an image editing unit that edits and processes the image data on a band-by-band basis;
an engine unit that drives the registration rollers arranged in the transport path to transport the output paper to the transfer roller;
The distance from the registration roller to the transfer roller, the speed at which the engine section conveys the output paper, the speed at which the image reading section reads the document, the size of the document, and the processing required for editing by the image editing section a calculation unit that calculates the number of preceding transport bands in the output paper based on time;
and an engine control section that controls the engine section such that the registration roller conveys the output paper to the transfer roller by the number of preceding conveyance bands. 2. The image forming apparatus according to claim 1, wherein the calculation unit calculates the number of preceding transport bands by calculating the following formula.

Number of unprocessed bands = (L1/V1)/(L2/V2+T1)
Total number of bands = (L3/L2)
Number of preceding transport bands = (Total number of bands - Number of unprocessed bands)

L1: Distance from registration roller to transfer roller L2: Length of 1 band L3: Size of document V1: Speed at which output paper is conveyed by engine V2: Speed at which image reading section reads document T1: Editing by image editing section Processing time per band required for processing

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