JPH05107853A - Image recorder - Google Patents

Abstract

PURPOSE:To shorten the image forming time by carrying out the image formation at normal speed when the original is a black image or when a black toner is specified by changing the image forming speed of regular paper and image forming speed of pet material sheet when forming an image utilizing color toner and by slowing down the image forming speed for the pet material sheet and improving translucency of a color image. CONSTITUTION:In the image reader provided with a mode 53 transferring and recording the color toner image on the regular paper and a mode 51 to transfer the color toner image to the pet material sheet, when the color toner image is transferred to the pet material sheet (hereafter OHP sheet), the translucency of the color toner is improved by changing over the device to a slow OHP mode 51 and carrying out transferring and recording at the same mode as the regular paper mode 53 transferring and recording the color toner image on the regular paper when a signal to transfer the black toner to the OHP sheet is inputted to the image recorder from the original or an image inputting device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording apparatus such as a copying machine or a printer which can record an image on plain paper and can record an image on a pet material sheet by switching modes.

[0002]

2. Description of the Related Art It has become common to use electrophotographic processes to form color toner images on plain paper or pet material sheets with color toners using copying machines or printers. In such an image recording apparatus, when a color image is formed using the pet material sheet, it is possible to obtain a clearer projection when the color image on the pet material sheet is translucent. The copy mode is set to the pet material sheet exclusive mode and the image forming speed is set to be slower than the plain paper copy mode. Therefore, when a color image is transferred and fixed on a pet material sheet, it takes more time than in normal mode copying. However, the color image is not always transferred to the pet material, and when the normal black image is transferred and fixed by using the black toner, the translucency as described above is not necessary, but the pet material as described above is required. However, there is a drawback that the image forming speed becomes slow due to the operation of the copy mode.

[0003]

As described above, when forming an image using color toners, the image forming speed of plain paper and the image forming speed of a pet material sheet are changed, and the image forming speed is changed in the case of a pet material sheet. It has been dropped to improve the translucency of color images. However, when black toner is transferred and fixed on the pet material sheet as described above, it is not necessary to obtain translucency, and it is sufficient if the black toner is sufficiently transferred onto the pet material sheet. Therefore, when the original is a black image or when the black toner is designated, the image forming time can be shortened at a normal image forming speed. The present invention is intended to solve the above problems.

[0004]

SUMMARY OF THE INVENTION The present invention for solving the above-mentioned problems is generally carried out in an image recording apparatus for forming a color toner image on an image carrier by using an electrophotographic process system. The image recording apparatus has a toner image transfer by paper, a switching means for switching the mode of the image recording apparatus at the time of transferring the toner image by the pet material sheet, and an image discrimination means for discriminating an image, and the image recording apparatus is configured by the mode switching means. When the mode is switched to the pet material sheet mode and the image printing is judged to be all black by the image judging means, the mode of the image recording apparatus is configured to perform the toner image formation in the plain paper mode. This is achieved by a characteristic image recording device.

[0005]

In the image recording apparatus having the mode for transferring and recording the color toner image on the plain paper as described above and the mode for transferring the color toner image on the pet material sheet, the pet material sheet (hereinafter referred to as OHP sheet) is colored. When the toner image is transferred, the mode is switched to the slow mode to improve the translucency of the color toner, and a signal for transferring the black toner to the OHP sheet is input to the image recording device by the original document or the image input device. At this time, the transfer recording is performed in the same mode as the mode for transferring and recording the color toner image on the plain paper.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, reference numeral 1 denotes a lower frame of an image forming apparatus, and a half-moon-shaped paper feed roller 2 for feeding a recording paper P is provided in the lower frame 1 and a plurality of the recording papers P are incorporated. The paper feed cassette 3 is detachably attached to the lower frame 1.
A push-up plate 4 which is pushed up by a spring 5 is provided in the paper feed cassette 3, the recording paper P is placed on the paper feed cassette 3, and a separation claw 6 rotatably provided on a part of the paper feed cassette 3 is used for recording. The paper P is locked at the top of the tip. Reference numeral 7 is a guide plate for guiding both sides of the recording paper P, which is plain paper, and is provided so as to be adjustable according to the size of the recording paper. The above configuration is provided in the paper feed cassette 3. Reference numeral 8 denotes a conveyance roller for the recording paper P provided on the lower frame 1, and the recording paper P fed by the paper feed roller 2
It is provided between a guide plate 9 for guiding the tip of the and a reverse guide plate 10.

Reference numeral 11 denotes a guide plate for guiding the recording paper P to the second paper feed roller 12 after the recording paper P is reversely fed, and guides the recording paper P to the second paper feed roller 12. 13 is the second paper feed roller 12
The sensor S1 for detecting the recording paper P at the position
It is a guide member that turns off and on. 14 is the second paper feed roller 12
Is a guide plate that guides the recording paper P passing through to the transfer belt 15 in the direction of the transfer belt 15. The transfer belt 15 includes a transfer roller 16 and a roller.
It is suspended on 17 and a drive roller 18. Reference numeral 15a is a cleaning means for cleaning the surface of the transfer belt 15. Reference numeral 19 denotes a fixing device for fixing the image transferred onto the recording paper P. The fixing device 19 is composed of a fixing heating roller 20 and a pressure contact roller 21, and a cleaning roller 20a is pressed against the fixing heating roller 20 and cleaned according to the rotation. To do. 22 is a fixing device 19
With the discharge roller for discharging the recording paper P, the swinging member 23 for turning on and off the sensor S2 for confirming the discharge of the recording paper P is operated by the recording paper at the time of discharging. The discharged recording paper P is recorded on a recording paper guide member 24, a guide passage 25 formed in the upper frame 1c, and guide conveying rollers 26, 27 on a paper discharge tray 28 provided in the upper part of the upper frame 1c. The paper P is configured to be discharged.

Next, a photosensitive drum 29 for image formation is provided in the substantially central portion of the upper frame 1c, and four sets of developing devices 30, 31, 32, 33 are arranged from the upper side along the surface of the photosensitive drum 29. Is a developing device frame 30a, and the developing device frame 30a has four sets of developing devices 30, 31 for three primary colors yellow, magenta, cyan, and black, as shown in FIG. 32,3
Gears (not shown) for independently operating each of the three by using drive switching means or the like are provided. A polygon mirror 34 reflects the laser light emitted from the laser light source 35 by the reflection mirrors 36, 37 and 38 to expose the photosensitive drum 29. Reference numeral 39 denotes an optical system frame body integrally incorporating optical systems such as the polygon mirror 34 and the reflection mirrors 36, 37, 38, which is incorporated in the uppermost part of the upper frame body 1c.

Reference numeral 40 denotes a charging electrode for charging the entire surface of the photosensitive drum 29, which is provided on a part of the upper frame 1c. 41
Is a cleaning blade for cleaning the residual developer adhering to the surface of the photosensitive drum 29 after transferring the image from the photosensitive drum 29 to the recording paper P, and for receiving the cleaned developer and discharging it to the outside. A carrying device 43 is provided, and a developer receiving member 42 that efficiently sends the developer scraped off by the cleaning blade to the carrying device 43 is provided below the cleaning blade 41. The developer conveyed to the outside by the conveying device 43 is conveyed to the container 44 by the conveyor 45 so that the developer can be accumulated in the container 44 up to an appropriate amount, and can be removed and discarded. Reference numeral 46 denotes a developer container for supplying a developer to each of the developing devices 30, 31, 32 and 33, and although the illustrated developer container is only one set, four developer containers are provided side by side. For example, cyan, magenta, yellow, and black color developers are supplied to 30, 31, 32, and 33 to perform color development. Reference numeral 47 is a manual tray that allows the recording paper P to be manually fed. The lower frame body 1 and the upper frame body 1c are assembled around the support shaft 1b so that the conveyance path of the recording paper P can be opened. When at least the fixing device 19 is not reached, the upper frame 1c is opened around the support shaft 1b,
The recording paper P can be taken out. Further, there is provided a guide plate 1a which allows the recording paper P provided on the lower frame 1 to be supplied from another paper feeding device (not shown).

The recording paper P is fed by the paper feed roller 2, conveyed by the conveyance roller 8, and then temporarily stopped by the second paper feed roller 12. Then, the recording paper is started to be fed from the second paper feed roller 12 so as to match the image formed on the photosensitive drum 29.

The present invention is configured as described above, and the light emission is controlled by the image signal input from the outside.
A laser beam is emitted from 35, and the polygon mirror 34 exposes the laser beam to the photosensitive drum 29 charged by the band electrode 40 via the reflection mirrors 36, 37, 38. The latent image formed by exposure is rotated a plurality of times by rotating the photoconductor drum 29 by the developing devices 30, 31, 32, and 33 having yellow, magenta, cyan, and black toners, respectively, and sequentially developing the color toners. A color toner image is formed on the surface of the photosensitive drum 29.
In order to transfer the color toner image to the recording paper P, the recording paper P in the paper feed cassette 3 is started to be fed by the paper feed roller 2, and the recording paper P is fed to the second paper feed roller 12 via the conveyance roller 8. Then, the second paper feed roller 12 and the stopper 48 accurately align and feed the recording paper P so that the portion of the photosensitive drum 29 on which the color toner image is formed coincides with the recording paper P. The recording paper P on which the color toner image has been transferred is sent between the fixing heating roller 20 and the pressure contact roller 21 to be thermally fixed, and then discharged to the paper discharge tray 28. The above is plain paper recording paper P
It is a means to transfer and fix the color toner image onto the
On the other hand, when the color toner image is transferred and fixed on the OHP sheet P1, the OHP sheet P1 is placed on the manual tray 47 as shown in FIG. 1, and the front end of the OHP sheet P1 is the portion of the second paper feed roller 12. Insert until. As a normal recording method, application software on a host computer (not shown) is used to specify to the image forming apparatus, which is a printer, whether the recording paper P is a plain paper or the OHP sheet P1, and the specification information is sent. .. In the case of the OHP sheet P1 for manual operation, for example, the push button 49 for the OHP sheet P1 provided in the vicinity of the hand rest 47 of the upper frame 1c of the image forming apparatus is pressed to switch the mode. The mode switching is input to the input port 50 as shown in FIG. 2 by the signal sent from the application software or by the manual operation, and the microcomputer 51 if the OHP sheet P1.
More OHP mode is output, and the microcomputer 51
Is input to the input port 52. The push button 49a is used to input the application software on the host computer or whether the image color is black toner or the color toner is used in the input port 52. When the black toner is used, the microcomputer 53 is used in the plain paper mode. Toner image formation is performed. That is, when the black toner is transferred and fixed on the OHP sheet P1, image recording is performed at the same speed as the processing speed of plain paper. Meanwhile the input port
When the black toner information is not input to the 52 with the push button 49a, the microcomputer 51 changes the mode to the OHP sheet mode by receiving the NO signal from the input port 52, and the color formed on the photoconductor drum 29. The toner is transferred and fixed on the OHP sheet P1. in this case,
An image forming mode is set in order to reduce the transfer and fixing speeds in order that the color toner on the OHP sheet P1 has a light-transmitting property. The above is the method of transferring the black toner onto the OHP sheet by the push button operation. However, FIG. 3 shows a means for automatically switching the operation using a normal image recording apparatus such as a copying machine. Is. Reference numeral 54 denotes a copying machine main body, and a platen glass plate 55 is provided above the copying machine 54.
And an original pressing plate 56 for pressing the original D placed on the original glass plate 55. Reference numeral 57 is a lamp for illuminating the original, and the reflected light of the original D emitted by the lamp 57 is reflected by mirrors 58, 59, 60.
Then, the surface of the photosensitive drum 69 is exposed by the mirror 64 via the imaging lens 63. Reference numeral 61 is a detection means for receiving and detecting whether the image surface of the original document D is a black color image or not.
Input means 62 for inputting the image of the document D from the detecting means 61
To provide. 65, 66, 67 and 68 are developing devices for developing yellow, magenta, cyan and black, respectively, and 70 is the photosensitive drum 69.
A band electrode that gives an electric charge to the surface, 71 is a manual paper feed table, and 72,7
Reference numeral 3 is a paper feed cassette in which the recording paper P is incorporated. 74,75
Is a paper feed roller for feeding the recording paper P, and double feed preventing devices 76, 77 for surely feeding only one fed recording paper P are provided in the paper feeding direction. .. Reference numeral 78 denotes a second paper roller pair for feeding the image formed on the photoconductor drum 69 so that the transfer position of the recording paper P coincides with each other, and 79 denotes a toner image transferred from the photoconductor drum 69 onto the recording paper P. A transfer electrode 80 for separating the recording paper P from the surface of the photosensitive drum 69, and a conveyer 81 for conveying the recording paper P on which the toner image is transferred to the thermal fixing device 82. A pressure roller 83 for pressure-bonding the recording paper P to the heat fixing device 82 is provided.

Next, the operation of the copying machine 54 will be described. First, the original D is placed on the original platen glass plate 55 and pressed by the original pressing plate 56. Next, the start button (not shown) of the copying machine 54 is pressed to turn on the lamp 57 and start the irradiation of the document D. By exposing the document D, the surface of the document D is sequentially exposed,
The image of the document D is exposed on the photosensitive drum 69 charged by the band electrode 70 by the reflected light of the mirror 64 from the mirrors 58, 59 and 60 via the image forming lens to form a latent image. Mirror in this case
The mirrors 59 and 60 are configured to perform 1/2 operation with respect to 58 operation of 1. On the other hand, the document D illuminated by the lamp 57
Is detected by the light receiving detection means 61 via the mirrors 58, 59, 60, and the input means 62 determines whether the document D surface is a color image or a black image. Now, the OHP sheet P1 is placed on the manual paper feed table 71, the copying machine 54 is switched to the OHP mode, and the paper feed roller 74 is started at the same time when the start button is pressed to start the OHP sheet P1.
Feed 1 OHP sheet P1 is a double feed prevention device 76,77
One sheet is surely fed by passing through, and is stopped by the second pair of sheet feeding rollers and stands by.

The image on the surface D of the original is the received light detecting means 61.
If it is detected by the input means 62 and the input means 62 determines that it is a black image, the input port 50 causes the microcomputer 51 to switch to the OHP mode, and the OHP sheet P1 is input by the input means 62 according to the input mode 52 and the original image is displayed. Is inputted to the microcomputer 53. Therefore, the developing device 68 develops the black toner on the photosensitive drum 69, and the transfer pole 79 develops the black toner on the OHP sheet P1. In this case, all the modes of the copying machine 54 are processed in the plain paper mode.

On the other hand, when the surface D of the original is a color image,
As described above, when the copying machine 54 is started, the surface of the document D is illuminated by the lamp 57, and the light receiving detection means 61 causes the input means 62.
To the OHP mode by the input port 50 in this case as well, when the microcomputer 51 is switched to the OHP mode, the input mode 52 is input from the microcomputer 51.
It is transmitted from the signal inputted to the document D that the document D is not a black image, and the microcomputer 51 again confirms that it is in the OHP mode. Accordingly, the copier 54 operates in OHP mode. Next, the color images on the surface of the document D are sequentially exposed and a color toner image is formed on the photosensitive drum 69 by the developing devices 65, 66 and 67 by the copying process action, and the black toner transfer of the black image on the OHP sheet P1 is performed. Compared with the time, the color toner is transferred to the OHP sheet at a low speed so as to obtain translucency and is fixed by the thermal fixing device 82.

[0015]

As described above, the present invention is based on the OHP sheet P1.
In order to change the process speeds of the transfer and fixing of the color toner image and the transfer and fixing of the black toner image to give the light-transmitting property, especially the OHP sheet is slower than other process speeds, and a clear color image can be obtained at the time of projection. As described above, the OHP sheet P1 is transferred and fixed on the OHP sheet, and the black toner is transferred and fixed. Therefore, the transparency of the toner is not necessary. Therefore, when the black toner image is obtained on the OHP sheet P1, the copying can be efficiently performed without decreasing the copying speed.

[Brief description of drawings]

FIG. 1 is an overall vertical sectional view of an image recording apparatus embodying the present invention.

FIG. 2 is a partial configuration diagram in which the present invention is used in a copying machine having a document table.

FIG. 3 is a flow chart diagram for performing the operation of the present invention.

[Explanation of symbols]

 1 Lower frame 2,74,73 Paper feed roller 3,72,73 Paper feed cassette 12,78 Second paper feed roller 15 Transfer belt 20,82 Heat fixing roller 29,69 Photosensitive drum 30,31,32,33 , 65,66,67,68 Developing device 35 Laser light source 36,37,38,57,58,59,60,64 Mirror 41 Cleaning blade 49 OHP sheet push button 49a Black toner information push button 50,52 Input port 51,53 Microcomputer 55 Original platen glass plate 61 Light receiving detection means 62 Input means 79 Transfer pole 84 Cleaning device P1 OHP sheet P Recording paper

Claims (2)

[Claims] 1. An image recording apparatus for forming a color toner image on an image bearing member by using an electrophotographic process method, the method comprising:
The image recording apparatus has a switching means for switching the mode of the image recording apparatus at the time of transferring the toner image by the pet material sheet, and a print determination means for discriminating the image, and the image recording apparatus is switched to the mode of the pet material sheet by the mode switching means. The image recording apparatus is characterized in that when the image is judged to be printed in black by the image judging means, toner image formation is performed in the plain paper mode as the mode of the image recording apparatus. 2. The image recording apparatus according to claim 1, further comprising a discriminating unit for discriminating an original image by the image discriminating unit.