JPH0635276A - Image forming device - Google Patents

Abstract

PURPOSE:To form an excellent image whatever recording paper is supplied to an image forming part by providing a detection means discriminating a plain paper or an OHP sheet in a device. CONSTITUTION:A 2nd paper supply roller 8 is adjusted so that recording paper P is stopped after advancing until the leading edge of the paper P is butted against a projection 14B projecting in a guiding plate 14 when it is driven. At such a time, on or off information is inputted in a CPU through an input/ output device T1 by a detection means S1, and the quality of the paper P is detected by a detection means S3 detecting the quality of the paper P through the input/output device T2 from the CPU. In the case the paper P is the plain paper, for example, information on the plain paper is inputted in the CPU from the detection means S3 through the device T2 and inputted in the process control means of the image forming device from the CPU, so that the control of an electrostatic charging pole for a photosensitive drum 29, a charge amount for a transfer belt 15, and the heating amount of the heating roller of a fixing device is performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus for transferring an image formed on an image bearing member onto recording paper, fixing the image, and recording the image. The present invention relates to a device for supplying and recording recording paper.

[0002]

2. Description of the Related Art Conventional recording sheets of different types,
For example, in an apparatus for transferring and recording an image using plain paper and a pet material sheet (hereinafter referred to as an OHP sheet), a plain paper is generally used in a cassette or the like for feeding a paper, while an OHP sheet is used. A manual paper feeding device provided for feeding special paper is provided to perform paper feeding using the device.
The image was being formed. The image forming apparatus usually records on plain paper in many cases, and the voltage of the transfer electrode, for example, is adjusted so as to be the best for transferring to the plain paper from the photoreceptor on which the toner image is formed. Therefore, when feeding an OHP sheet from the manual feed device and transferring an image,
It was necessary to switch the process for P and the switch button provided in a part of the apparatus was operated.

[0003]

However, the above-described switching operation is performed for an extremely special sheet such as an OHP sheet, and switching is not necessary for a special size plain paper. Therefore, when the OHP sheet is fed, the operation of the switching button is often forgotten, and there is a problem that a good image cannot be obtained.

In order to solve the above-mentioned problems, the present invention is provided with a detecting means for detecting plain paper and OHP sheet in the apparatus, whichever recording paper is fed to the image forming section. The purpose is to form a good image.

[0005]

In order to achieve the above object, a paper feeding means for separating and feeding a plurality of recording papers stored in a cassette one by one, and a paper feeding for manually feeding the recording papers. In the image forming apparatus including the means, a common paper feeding path is configured by using a paper feeding path for feeding the recording paper from the cassette and a paper feeding path for feeding the recording paper by the manual feeding, A stop means for temporarily stopping the recording paper provided in the common paper feeding path and a detection means for stopping the recording paper by the stopping means or for detecting the quality of the recording paper being conveyed are provided near the common paper feeding path. This is achieved by an image forming apparatus characterized by being provided.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, reference numeral 1 is 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 that 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 uppermost end 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 is a second paper feed roller for the recording paper P provided on the lower frame 1, and is provided between a guide plate 9 for guiding the leading end of the recording paper P fed by the paper feed roller 2 and a reversing guide plate 10. Has been.

Reference numeral 11 is a guide plate for guiding the recording paper P to the third paper feed roller 12 after reversing the paper feed, and 13 is for detecting the recording paper P at the position of the third paper feed roller 12. Detection means S
This is a guide member that turns 1 on and off. Reference numeral 14 is a guide plate for guiding the recording paper P, which has passed through the third paper feed roller 12, toward the transfer belt 15, and a stopper having a protrusion 14B projecting to the paper feed passage 14A in a part of the guide plate 14. 14C is provided. The transfer belt 15 includes a transfer roller 16 and rollers 17, 17
A and a driving roller 18 are suspended. 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, which is composed of a fixing heating roller 21 and a pressure roller 20, and a cleaning roller 20a is brought into pressure contact with the pressure roller 20.
Clean according to rotation. A discharging roller 22 discharges the recording paper P by the fixing device 19. The swinging member 23 for turning on and off the sensor S2 for confirming the discharging of the recording paper P is operated by the recording paper when discharging. Recording paper P discharged
The recording paper guide member 24, the guide passage 25 formed in the upper frame 1c, and the guide transport rollers 26, 27 eject the recording paper P to the paper ejection tray 28 provided above the upper frame 1c. Is configured. Reference numeral 48 denotes a tray extended to the paper discharge tray 28 and fixed to the upper frame 1c by a shaft 50 so as to have an abutting portion 49.
And a discharge tray surface 48a.

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 above 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, 31 for yellow, magenta, cyan, and black of three primary colors 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 reflecting 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 strip 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 transported to the outside by the transport device 43 is transported to the container 44 by the conveyor 45 so that an appropriate amount can be accumulated in the container 44, and the developer 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 has only one set, four sets 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 51 is a gear for supplying toner to the developer container 46, and 52 is a driving means. Reference numeral 47 is a manual tray which can manually feed the recording paper P. The lower frame 1 and the upper frame 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 can be opened around the support shaft 1b and the recording paper P can be taken out. Further, there is provided a guide plate 1a that 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 second paper feed roller 8, and then temporarily stopped by a stopper 14C provided near the third paper feed roller 12. Then, the recording paper is started to be fed from the third 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 and 38. The developing device 30, 31, 32, 33 for holding the latent image formed by exposure with yellow, magenta, cyan and black toners,
Is rotated a plurality of times to successively superimpose color toners for development to form color toner images on the surface of the photosensitive drum 29. In order to transfer the color toner image onto 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 third paper feed roller 12 is passed through the second paper feed roller 8.
The recording paper P is fed to the recording paper P, and the projection 14B provided between the paper feed roller 12 and the transfer belt 15 accurately aligns the recording paper P with the portion of the photosensitive drum 29 on which the color toner image is formed. Send it. The recording paper P on which the color toner image is transferred is fixed to the heating roller 21 and the pressure roller 20.
After being sent in between, the heat fixing is performed, and the sheet is discharged to the sheet discharge tray 28. The above is the means for transferring and fixing the color toner image on the plain recording paper P.

FIG. 2 shows an embodiment of the present invention, in which the recording paper P stored in the paper feed cassette 3 in response to a recording start signal is
Only one sheet is separated by the separation claw by the sheet feeding roller 2,
The recording paper P is conveyed by the paper feed roller 8 and the recording paper P is turned over to the reverse guide plate 10.
Is guided in the direction of the guide plate 11. The leading end of the recording paper P presses the guide member 13 provided in the downstream direction of the guide plate 11 to turn on or off the detecting means S1 so that the third paper feeding roller.
12 rotations stop. The third paper feed roller 12 may rotate continuously with respect to the recording paper P without rotating. In the case of driving, the second paper feed roller is adjusted so that the leading end of the recording paper advances and stops until it hits the protrusion 14B protruding into the guide plate 14.
At this time, ON or OFF information is input to the CPU via the input / output device T ₁ by the detection device S1, and the detection device S detects the quality of the recording paper P from the CPU via the input / output device T _2.
3 to detect. The recording sheet P, for example in the case of ordinary paper information of plain paper through the input-output device T ₂ from the detection device S3 enters a CPU, is input to the process control means of the image forming apparatus from the CPU, for example, a photosensitive drum From the control of the strip electrode 40 for 29, the charge amount for the transfer belt 15 and the heating amount of the heating roller 21 of the fixing device 19 are controlled. In this way, the color toner image formed on the photosensitive drum 29 is transferred onto the recording paper P, and the fixing device 19 performs heat fixing to obtain a good transferred image. As a means for detecting the recording paper P by the detecting means S3, a stopper 14C is urged in one direction by a spring 14D so that the projection 14B always protrudes into the paper feed passage 14A. Is stopped by hitting the protrusion 14B, and the paper quality is surely detected by the detecting means S3. Next, a toner image is formed on the surface of the photoconductor drum 29 by the developing devices 30, 31, 32, and 33, and a transfer start signal is supplied from the CPU to the solenoid 14E via the input / output device T ₃ to resist the spring 14D. Then stopper
By operating 14C to one side and retracting the protrusion 14B from the paper feed path 14A, the recording paper P is conveyed by the third paper feed roller 12 toward the photosensitive drum 29 and the transfer belt 15.

The detection means S3 can be used in either a reflection type detection method or a transmission type detection method.

Next, as shown in FIG. 2, when the OHP sheet P1 is placed on the manual tray 47 and manually inserted into the guide plate 11 in the direction of the arrow, the guide member is introduced at the tip of the OHP sheet P1. Push 13 to turn sensor S1 ON or OFF.

In this case, the image recording apparatus is stopped and the third paper feed roller is not rotating. Therefore, OHP sheet P
1, the third paper feed roller 12 is rotated continuously, and enters the projection 14B protruding into the guide plate 14 and stops there. That is, in this state, the input / output device T is turned on by the ON or OFF signal of the sensor S1.
_A signal is input to the CPU via 1 and the quality of the OHP sheet P1 is detected by the detecting means S3 from one of the CPUs via the input / output device T ₂ . Here OHP sheet information from the detecting device S3 if the recording sheet is an OHP sheet P1 is input to the process control means of the image forming apparatus than the CPU enters the input-output device T _2, as the example, a photosensitive drum 29
The control of the charge amount to the transfer belt 15, the heating amount of the heating roller 21 of the fixing device 19, and the like are performed from the control of the belt electrode 40 for the. In such a controlled state, a signal is output from the CPU to the input / output device T ₃ and the solenoid 14E is set to the spring 14D.
The projection 14B is retracted from the paper feed path 14A, and the third paper feed roller 12 is rotated at the same time to convey the OHP sheet P1 toward the photosensitive drum 29 and the transfer belt 15.

[0016]

It is an object of the present invention to provide a sheet feeding device having a plurality of sheet feeding paths, a detecting means for connecting the plurality of sheet feeding paths to a common sheet feeding path and detecting the paper quality in the common sheet feeding path. S3
Is provided, and when the plain paper or the OHP sheet is temporarily stopped or the paper OHP sheet is the second
Since the paper quality is automatically detected while the paper is being conveyed by the paper feed roller and the third paper feed roller, it is not necessary to manually switch the image forming process depending on the paper quality. Even if an image is recorded, a good copy image can always be obtained.

[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 configuration diagram of cassette sheet feeding and manual feed.

[Explanation of symbols]

1 Lower Frame 2 Paper Feeding Roller 3 Paper Feeding Cassette 8 Second Paper Feeding Roller 12 Third Paper Feeding Roller 14A Paper Feeding Path 14B Protrusion 14C Stopper 14D Spring 14E Solenoid 15 Transfer Belt 20 Crimping Roller 29 Photosensitive Drum 30,31, 32,33 Developing device 35 Laser light source 36,37,38 Reflecting mirror 41 Cleaning blade S3 Detecting means T ₁ , T ₂ , T _{3 I} / O device

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location B65H 11/00 J 7111-3F

Claims (1)

[Claims] 1. An image forming apparatus comprising: a paper feeding unit that separates and feeds a plurality of recording papers stored in a cassette one by one; and a paper feeding unit that manually feeds the recording papers.
A common paper feeding path is formed in which a paper feeding path for feeding the recording paper from the cassette and a paper feeding path for feeding the recording paper by the manual feeding are formed in common, and the recording provided in the common paper feeding path. An image forming apparatus characterized in that a stop means for temporarily stopping the paper and a detecting means for stopping the paper by the stop means or for detecting the paper quality of the recording paper being conveyed are provided in the vicinity of the common paper feed path. .