JPH0558504A - Paper feed controller of transfer paper at image formation device - Google Patents

Abstract

PURPOSE:To prevent dirt at a transport passage or the like and make the labor of transfer paper setting simple by equipping a paper feed stopping means which stops the action of parallel paper feed mechanisms when at least one of the plural paper sheet detecting means in a paper feed cassette detects the non-presence of paper sheets. CONSTITUTION:A paper feed cassette is equipped at its inside with paper arrangement units in parallel with each other, and an image formation device possesses paper sheet sensors 1a, 1b to detect the presence of transfer paper in the paper sheet arrangement units, and at the same time possesses sensors such as a dual delivery sensor 17 to detect the dual delivery of transfer paper, a resist sensor 18 for the timing of a pair of resist rollers, timing sensor 19 for a light emitting portion or the like, and a discharge sensor 20 for transfer paper. A mechanism control portion 26 controls a main motor 21, clutches 22, 23 or the like in response to detection signals or the like from sensors 1a, 1b, 17-20. And, the mechanism control portion 26 possesses a paper feed stopping means 261 which stops the action of paper feed mechanisms or the like in a case in which no presence of paper sheets is detected by means of either of paper sheet sensors 1a, 1b.

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 which feeds transfer papers stored in parallel in paper feed cassettes in parallel and forms images on the respective transfer papers.

[0002]

2. Description of the Related Art Conventionally, an image forming apparatus such as a printer is known which prints addresses and the like sequentially output from a data storage unit such as a personal computer.

In this type of image forming apparatus, transfer papers such as envelopes are accommodated in two rows in parallel in a paper feed cassette, the left and right transfer papers are fed in parallel, and then the left and right transfer papers are transferred to the left and right transfer papers. Image formation is performed by simultaneously transferring the toner images formed on the photoconductors and the like.

[0004]

In such an image forming apparatus, until all of the transfer sheets are fed, that is, even when one of the left and right transfer sheets in the sheet feeding cassette is used up, the other transfer sheet is not fed. Paper feeding and parallel formation of toner images are continued until the transfer paper runs out. For this reason, the toner image on the side where the transfer paper has disappeared adheres to the transfer device and the conveying path on the downstream side thereof, and the conveying path is contaminated. Moreover, the next-time transfer paper will be soiled.

As a countermeasure against this, the right and left transfer sheets in the paper feed cassette may be set so as to match each other, but it is troublesome to accurately count the transfer sheets each time.

The present invention solves the above-mentioned problems, and is an image forming apparatus for stopping or notifying the feeding when at least one of the transfer sheets stored in parallel in the feeding cassette runs out of paper. An object of the present invention is to provide a paper feed control device for transfer paper.

[0007]

In order to achieve the above object, the present invention provides a paper feed cassette for accommodating transfer papers in parallel, and a parallel feed for parallelly feeding the transfer papers in each row from the paper feed cassette. In an image forming apparatus having a paper mechanism and an image forming means for forming an image on the transfer paper every time the transfer paper is fed, a plurality of units for respectively detecting the presence or absence of the transfer paper in each row in the paper feed cassette are provided. And a paper feed stopping means for stopping the operation of the parallel paper feed mechanism when at least one of the plurality of paper detecting means detects the absence of paper.

Further, according to a second aspect of the present invention, a paper feed cassette for storing the transfer papers in parallel, a parallel paper feed mechanism for feeding the transfer papers in each row in parallel from the paper feed cassette, and the transfer papers are fed. In an image forming apparatus having an image forming means for forming an image on the transfer paper for each, a plurality of paper detecting means for detecting the presence or absence of the transfer paper in each row in the paper feeding cassette, and a plurality of paper detecting means At least one of the means includes an informing means for informing the absence of the paper when the absence of the paper is detected.

[0009]

According to the transfer paper feed control device in the image forming apparatus having the above-described structure, the transfer papers of the respective rows in the paper feed cassette are simultaneously fed in parallel by the parallel paper feed mechanism, and the transfer papers are fed. And each transfer paper is imaged. At this time, the paper detection means separately detects the presence or absence of the transfer paper in each row for each sheet feeding, and when at least one of the transfer papers in each row is out of paper, the transfer papers in the other rows are detected. The operation of the parallel sheet feeding mechanism is stopped regardless of the presence or absence of.

Further, according to the transfer paper feed control device in the image forming apparatus of the second aspect, the transfer papers of the respective rows in the paper feed cassette are simultaneously fed in parallel by the parallel paper feed mechanism,
When the transfer paper is fed, an image is formed on each transfer paper. At this time, the paper detection means separately detects the presence or absence of the transfer paper in each row for each paper feed, and when the paper out occurs in at least one of the transfer papers in each row, the paper out is notified.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 3 is a schematic diagram showing an example of an image forming apparatus equipped with a parallel sheet feeding mechanism according to the present invention. The image forming apparatus is provided with a paper feed cassette 4A for normal paper, a paper feed cassette 4B for parallel paper feed, paper feed rollers 5A and 5B, a pair of separation rollers 6, a pair of registration rollers 7, a photoconductor 8 and its surroundings. Image forming means (not shown), a light emitting unit 9 including a laser, a polygon mirror 10, a transfer unit 11, a fixing unit 12 including a fixing roller, discharge roller pairs 13 and 15, a discharge guide 14, a discharge tray 16 and the like. It is composed of.

As shown in FIG. 4, the paper feed cassette 4B is internally provided with paper alignment units 40a and 40b in parallel, and the image forming apparatus includes the paper alignment unit 40.
a and 40b, which has a paper sensor 1 for detecting the presence or absence of transfer paper, and a double feed sensor 1 for detecting the double feed of transfer papers.
7, a registration sensor 18 for driving timing of the registration roller pair 7, a timing sensor 19 for emission start timing of the light emitting unit 9 and the like, and a discharge sensor 20 for detecting discharge of the transfer paper. It should be noted that these sensors detect the transfer papers fed in parallel, respectively,
Two are arranged side by side on the left and right.

The transfer sheets in the sheet feeding cassette 4B are fed in parallel by the sheet feeding roller 5B to the separating roller 6 in, for example, two rows, and are further conveyed in parallel one by one by the separating roller 6 to form a pair of registration rollers 7. Abut. The registration roller pair 7 is drive-controlled based on a signal from the registration sensor 18.

On the other hand, the photoconductor 8 is driven based on the signal from the timing sensor 19, and the image signal input from the data storage section outside the image forming apparatus is optically modulated to cause the light emitting section 9 to emit modulated light ( Laser light), and the photoconductor 8 is exposed by the laser light from the light emitting unit 9 through the polygon mirror 10. Image formation is performed on the photoconductor 8 in parallel in the axial direction of the photoconductor 8 by the above-described image forming means. That is, the surface of the photoconductor 8 is charged by a charging device (not shown), an electrostatic latent image is formed in parallel by the above exposure, and is visualized as a toner image by a developing device (not shown).

The toner image is transferred to each of the transfer sheets by the transfer unit 11, fixed by the fixing unit 12, and discharged to the discharge tray 16 by the discharge roller pair 13 and 15 via the discharge guide 14.

Next, an example of a specific structure of the paper sensor 1 will be described with reference to FIGS. 4 and 5. The sheet sensors 1a and 1b are arranged at appropriate positions on the apparatus main body side, and detect the presence or absence of transfer sheets in the sheet aligning units 40a and 40b, respectively. The paper sensors 1a and 1b are composed of, for example, photo interrupters 2a and 2b composed of a pair of light emitting element and light receiving element and actuators 3a and 3b rotatably interposed therebetween, and a paper aligning unit 40a,
They are arranged at appropriate places above 40b. The above-mentioned actuators 3a, 3b are the paper aligning units 40a, 40
transfer sheet P placed on the sheet placing plates 41a and 41b of b.
The top end is in contact with the uppermost stage of the. In addition, elongated holes 43a and 43b are formed at appropriate positions on the sheet placement plates 41a and 41b, for example, in parallel with the sheet feeding direction. It is designed to rotate up to.

The photo interrupters 2a and 2b are shown in FIG.
As indicated by the solid line in FIG. 5, the actuators 3a and 3b are turned off at positions where the actuators 3a and 3b are interposed in the gaps 31a and 31b between the light emitting element and the light receiving element. When it descends into the long holes 43a and 43b described above, it is turned on.

The sheet placing plates 41a and 41b are biased upward by the coil springs 42a and 42b so that the uppermost stage of the placed transfer sheet P abuts the sheet feeding roller 5B at an appropriate pressure. Is becoming

Next, an example of the configuration of the control system of the image forming apparatus will be described with reference to the block diagram of FIG. This control system includes an image control unit 25, a mechanism control unit 26, and the like. The image control unit 25 processes an image signal from a data storage unit outside the image forming apparatus and outputs it to the light emitting unit 9. The light emitting unit 9 does not operate when a low signal is output from the NOR circuit 262 described later. The mechanism control unit 26 controls the main motor 21, the clutches 22, 23, etc. according to the detection signals from the sensors 1a, 1b, 17-20. Further, the mechanism control unit 26 stops the operation of the paper feeding mechanism and the like when one of the paper sensors 1a and 1b detects that there is no paper.
It has 61. Further, the mechanism control unit 26 outputs a signal indicating the absence of paper to the display unit 24 to display the absence of paper when the absence of paper is detected.

The main motor 21 is composed of paper feed rollers 5A and 5B.
The separating roller pair 6 and the like are driven via clutches 22 and 23. When the sheet feeding clutch 22 is turned on, the driving force of the main motor 21 is transmitted to the sheet feeding mechanism such as the sheet feeding rollers 5A and 5B and the separating roller pair 6. When the conveying system clutch 23 is turned on, the driving force of the main motor 21 is transmitted to the transfer sheet conveying mechanism such as the registration roller pair 7 and the discharge roller pairs 13 and 15.

Next, an example of a specific structure of the mechanism control unit 26 will be described with reference to the circuit diagram of FIG. The mechanism control unit 26 includes inverters 261a and 261b, a NOR circuit 2
62, ROM 263, RAM 264, CPU 265, transistors Q1 to Q3, and the like. Integrating circuit 26
Reference numerals 0a and 260b each include a resistor and a capacitor, and the photo interrupter 2 of the paper sensors 1a and 1b.
Inverter 261 outputs a high signal when a and 2b are off.
a, 261b, and photo interrupters 2a, 2
When b is on, a low signal is sent to the inverters 261a, 2
It outputs to 61b. Inverter 261
Reference numerals a and 261b respectively invert the output signals of the integrating circuits 260a and 260b and output the inverted signals to the NOR circuit 262. The inverters 261a and 261b have a hysteresis characteristic to reduce the influence of chattering of the photo interrupters 2a and 2b together with the integrating circuits 260a and 260b. The NOR circuit 262 outputs a high signal to the CPU 265 when the output signals of the inverters 261a and 261b are both low signals.
When a high signal is output from at least one of 61a and 261b, a low signal is output to the CPU 265.

The CPU 265, when the high signal is output from the NOR circuit 262, the sheet aligning unit 40.
It is determined that there is a transfer sheet on both a and 40b, and in this case, the main motor 21 and the clutches 22 and 23 are driven through the transistors Q1 to Q3 to perform the sheet feeding operation and the like. Further, the CPU 265 has a NOR circuit 262
When a low signal is input from the sheet alignment unit 40
When it is determined that one of a and 40b is out of paper, the transistors Q1 to Q3 are turned off to stop the operation of the paper feed mechanism and the like.

The ROM 263 stores the main program and the like, and the RAM 264 stores various data and the like.

Next, an example of the operation of the above control system will be described with reference to the flowchart of FIG. First, when the operation starts, the main motor 21 is turned on (step S
1). Next, it is determined whether or not there is a transfer sheet in both the sheet alignment units 40a and 40b, that is, whether or not a high signal is input from the NOR circuit 262 to the CPU 265 (step S2).

Then, the sheet aligning units 40a, 40b
If there is a transfer sheet on both sides of the sheet, that is, if a high signal is input from the NOR circuit 262 to the CPU 265 (YES in step S2), the sheet feeding clutch 22 is turned on and each of the sheet aligning units 40a and 40b. The transfer papers are fed in parallel (step S3), and a toner image is formed on the photoconductor 8 in order to perform the transfer operation to the transfer papers fed in parallel. The toner image is transferred to the transfer papers fed in parallel. After that, it is fixed and discharged (step S4).

Thereafter, it is judged whether or not the transfer processing has been completed for all the number of sheets (step S5), and if the entire transfer processing has not been completed (NO in step S5), further transfer is performed. Return to S2. And
When the entire transfer process is completed (YES in step S5), the main motor 21 is turned off (step S6), and the process of this flowchart ends.

On the other hand, in step S2, when one of the sheet aligning units 40a and 40b runs out of paper and a low signal is input from the NOR circuit 262 to the CPU 265 (NO in step S2), the paper feeding operation is stopped. In order to do so, the process proceeds to step S6 without performing the processes of step S3 to step S5, the main motor 21 is turned off, and the sheet feeding mechanism such as the sheet feeding rollers 5A and 5B is stopped. Further, since the paper is not fed, the subsequent transfer operation is also stopped. Further, at this time, the display unit 2 is required to notify that there is no paper.
No. 4 is displayed on the screen.

In this way, the sheet aligning units 40a, 4
If there is no paper in any one of 0b, the main motor 21 is turned off and the paper feeding operation is stopped. It is possible to prevent the transportation path and the like from being soiled. Further, since no paper is displayed and the number of sheets to be set may be arbitrary, the transfer sheets can be set quickly.

In this embodiment, the transfer papers fed in parallel are two rows, but they may be three or more rows. In this case, the number of paper sensors 1 may be set according to the number of adopted columns.

Further, in this embodiment, the sheet aligning unit 4
If one of 0a and 40b is out of paper, the paper feeding operation and the like are stopped and the paper out is displayed. However, the paper out operation is not stopped and only the paper out display is performed. You may do it. Further, instead of the above-mentioned display of paper-out, or together with the display of paper-out, it may be notified by a buzzer or voice.

Further, in this embodiment, the paper sensor 1a,
Although the presence or absence of the transfer paper in the paper alignment units 40a and 40b is detected by the 1b to judge the stop of the paper feeding operation, instead of the paper sensors 1a and 1b, the double feed sensor 17 or the registration sensor 18 is used. The presence or absence of the transfer paper may be detected by a sensor.

[0032]

According to the present invention, when at least one of the transfer papers in each row runs out of paper, the operation of the parallel paper feed mechanism is stopped regardless of the presence or absence of the transfer papers in the other rows. It is possible to prevent the conveyance path and the like from being contaminated due to the paper feeding being continued in the state where there is no paper in only one row. Further, since it is not necessary to make the number of transfer sheets in each row uniform, it is easy to set transfer sheets.

Further, when at least one of the transfer papers in each row is out of paper, it is notified that there is no paper, so that the transfer paper can be set quickly after the detection of paper out.

[Brief description of drawings]

FIG. 1 is a block diagram showing an example of a control system of an image forming apparatus to which the present invention is applied.

FIG. 2 is a specific circuit diagram of a mechanism control unit.

FIG. 3 is a schematic configuration diagram illustrating an example of an image forming apparatus.

FIG. 4 is a sectional view showing an example of a parallel sheet feeding mechanism.

FIG. 5 is a side sectional view of a parallel sheet feeding mechanism.

FIG. 6 is a flowchart showing an example of a paper feeding control operation.

[Explanation of symbols]

 1, 1a, 1b Paper sensor 2a, 2b Photointerrupter 3a, 3b Actuator 4A, 4B Paper feeding cassette 5A, 5B Paper feeding roller 21 Main motor 22 Paper feeding clutch 23 Conveying system clutch 24 Display section 25 Image control section 26 Mechanism control Parts 40a, 40b Paper alignment units 41a, 41b Paper placement plates 42a, 42b Coil springs 43a, 43b Long holes 261 Paper feed stopping means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masami Fuchi 1-228 Tamazo, Chuo-ku, Osaka City Mita Kogyo Co., Ltd. (72) Kenji Oda 1-22-28 Tamazo, Chuo-ku, Osaka Mita Kogyo Co., Ltd. (72) Inventor Yoshinori Makiura 1-228 Tamatsukuri, Chuo-ku, Osaka Mita Kogyo Co., Ltd. (72) Hirohide Yamaguchi 1-2-2 Tamatsukuri, Chuo-ku, Osaka Mita Within Kogyo Co., Ltd.

Claims (2)

[Claims] 1. A paper feed cassette for accommodating transfer papers in parallel, a parallel paper feed mechanism for parallelly feeding the transfer papers in each row from the paper feed cassette, and the transfer papers every time the transfer papers are fed. In an image forming apparatus having an image forming unit for forming an image, a plurality of sheet detecting units for respectively detecting the presence or absence of transfer sheets in each row in the sheet feeding cassette, and at least one of the plurality of sheet detecting units. A paper feed control device for a transfer paper in an image forming apparatus, which comprises a paper feed stopping means for stopping the operation of the parallel paper feed mechanism when detecting the absence of paper. 2. A paper feed cassette for storing transfer papers in parallel, a parallel paper feed mechanism for feeding the transfer papers in each row in parallel from the paper feed cassette, and the transfer papers each time the transfer papers are fed. In an image forming apparatus having an image forming unit for forming an image, a plurality of sheet detecting units for respectively detecting the presence or absence of transfer sheets in each row in the sheet feeding cassette, and at least one of the plurality of sheet detecting units. A sheet feeding control device for a transfer sheet in an image forming apparatus, comprising: a notifying unit for notifying that there is no paper.