JPS6056751A - Paper supply device - Google Patents

Abstract

PURPOSE:To prevent unsatisfactory conveyance and a mistake in paper supply by providing a detector detecting presence of a form in a form conveyance route of a paper supply device for an electronic duplicator and setting, at a point of time when the detector detects presence of the form, a time until driving a conveyance means. CONSTITUTION:A paper supply device 13 is provided with paper supply cassettes (housing part) 14, 15, paper supply rollers (form feeding means) 16, 17 which feed form P by one sheet at a time and guide passages 18, 19, and further provided with a pair of aligning rollers (conveyance means) 20 which positions the tip of the form P sent through the guide passages 18, 19 and conveys it. Further, a detector 31 detecting presence of the form P is provided adjacently to the aligning rollers 20. Certain detection of a mistake in paper supply is made possible by setting a time for conveying the form up to the detector 31 longer than the actual time. By setting, after presence of the form P is detected by the detector 31, a timer which has set a time of conveyance up to the aligning roller 20, starting time of driving of the roller 20 can be set accurately.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a paper feeding device for feeding paper to an image transfer section in, for example, an electronic copying machine.

[Technical background of the invention and its problems] For example, in an electronic copying machine, a paper feeding device that supplies paper in a paper storage section (paper feeding cassette) to an image transfer section uses a paper feeding means (paper feeding roller) to store the paper. 1 paper in the department
The sheets are fed out one by one, and the fed out sheets are sent to the image transfer section by a conveying means (aligning roller). In this case, when a paper feeding command is given, a timer is set for operating the paper feeding means,
When the timer times up, the conveyance means is driven.

However, when setting the drive start time of the conventional conveyance means, the conveyance means cannot cope with temporal variations such as slippage between the paper conveyance means and the paper, which delays the conveyance time, and the image transfer This may lead to paper feeding errors. Further, even when no paper is actually sent out from the paper storage section, there is a problem in that the normal copying operation continues.

[Purpose of the Invention] The present invention has been made in view of the above circumstances, and its purpose is to provide a paper feed system in which the drive start time of the conveying means can always be optimally set and paper feeding errors can be reliably prevented. The goal is to provide equipment.

[Summary of the Invention] The paper feeding device of the present invention is provided with a detector that detects the presence or absence of paper in the transport path between the paper feeding means and the transporting means, and when the detector detects the presence of paper, the paper feeding device starts transporting the paper. The device is configured to set the time until the device is driven.

[Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 schematically shows an electronic copying machine equipped with a paper feeding device according to the present invention. In other words, 1 is the copying machine main body,
A document table (transparent glass plate) 2 for supporting a document 0 is provided on the upper surface of the main body 1, and a document table cover 3 is provided on the document table 2 so as to be openable and closable. The document 0 set on the document table 2 is exposed and scanned by the exposure lamp 4 and the mirrors 5, 6, and 7 reciprocating along the lower surface of the document table 2 in the direction of the arrow shown in the figure. configured to be used. In this case, mirror 6.1 moves at a speed of 172 of mirror 5 so as to keep the optical path length constant. The light reflected from the original 0 by the illumination of the exposure lamp 4 is reflected by the mirror 5°6.1, passes through the lens 8, is further reflected by the mirror 9, and is guided to the photosensitive drum 10 as an image carrier. Thus, the image of the document 0 is formed on the surface of the photosensitive drum 10. The photosensitive drum 10 rotates in the direction of the arrow shown in the figure, and its surface is first charged by the charging device 11. Then, the image of the document O is exposed to slit light to form an electrostatic latent image, and this electrostatic m The image is configured to be visualized by applying toner by a developing device 12.

Further, a paper feeding device 13 is provided below the developing device 12 for supplying the paper P to the lower part of the photoreceptor drum 10 (image transfer section 21).
is provided. This paper feeding device 13 is detachably attached to the side of the main body 1 and can feed a plurality of sheets of paper P.

Upper and lower paper feed cassette (storage section) 1 that stores...
4, 15, and a paper feed roller (paper feeding means) 16 that feeds paper P one sheet at a time from these paper feeding cassettes 14 and 15.
, 17, and a guide path 18.19 for guiding the paper P sent out by these paper feed rollers 16.17 are provided. A pair of aligning rollers (
20 and the like are provided. Note that one of the paper feed cassettes 14 and 15 can be selected on an operation panel (not shown).

Thus, the paper P conveyed by the aligning roller 20 is sent to the image transfer section 21. The paper P sent to the image transfer section 21 comes into close contact with the surface of the photoreceptor drum 10 at the transfer charger 22, so that the toner image on the photoreceptor drum 10 is transferred by the action of the charger 22. Ru. After the photosensitive drum 10 has been transferred, the charge is removed by the charger 23, the residual toner on the surface is removed by the cleaner 24, and the afterimage is erased by the charge removal lamp 25, so that it returns to its initial state. configured. On the other hand, the paper P after the transfer is electrostatically peeled off from the photosensitive drum 10 by the action of the peeling charger 26, and then transferred to the paper transport path 27.
is conveyed to the heat roller 28 as a fixing device by
By passing through this, the transferred image is heated and fixed. The sheet P after fixing is configured to be discharged to a tray 30 outside the main body 1 by a paper discharge roller 29.

In addition, the paper feed row 516.17 and the aligning roller 20
A detector 31 for detecting the presence or absence of paper P is provided near the aligning roller 20 on the conveyance path between the paper P and the alignment roller 20 . This detector 31 is an optical detector including, for example, a light emitting diode as a light source and a phototransistor as a light receiving element.

FIG. 2 shows a paper feed control circuit according to the present invention.

That is, Sl is a paper feed roller drive signal, S2 is a first cassette selection signal that is output when the paper feed cassette 14 is selected, S3 is a second cassette selection signal that is output when the paper feed cassette 15 is selected, CP is the clock pulse, R
1 is output in response to the need to reset the display. 33 is a first AND circuit, and the output of the first inverter circuit 34 is "1"1.
When the signal 81.82 is inputted, the signal 1"1" is outputted. 35 is a second AND circuit, and when the output of the second inverter circuit 36 is 111 II times signal, when the signal 81.32 is inputted, the signal 81.32 is inputted. 37 is a first output counter, which is set by the constant force signal of the first AND circuit 33, counts clock pulses CP, and outputs a 1 signal when the count is up. 38 39 is a first OR circuit, which is set to a set state by the output signal of the second AND circuit 35, counts clock pulses CP, and outputs a signal of ``1'' when counted up. When either of the two counters 37, 38 counts up, it outputs a "1" signal. 4o is a first gate circuit, and when the output of the first OR circuit 39 receives a "0" signal, a signal s1 is input. 41 is a second gate circuit, and when the signal s1 is not input, or the output of the first OR circuit 39 is "1" signal 1.
42 is the first FF circuit, which is set by the output signal of the first gate circuit 40 and outputs the second gate circuit 41.
It is reset by the output signal of 43 is a drive circuit, the first
When the FF circuit 42 is set, it operates and the paper feed roller 16
．． 17 drive motors 44 are driven.

The detector 31 is composed of a light emitting diode 31a and a phototransistor 31b as described above. When the paper P is not present between the light emitting diode 31a and the phototransistor 31b, the phototransistor 31b is turned on, and a low level signal is input to the inverting input terminal (-) of the comparator 45, indicating that the paper P is present. When the photo I-transistor 31b is turned off, a high level signal is input to the inverting input terminal of the comparator 45. Therefore, by setting the reference voltage VR input to the non-inverting input terminal (10) of the comparator 45 to an intermediate potential between the above-mentioned high level and low level, when the paper P reaches the detector 31, The comparator 45 outputs a signal of "1". 46 is a second OR circuit which outputs a ``1'' signal when the signal R2 or the output signal of the comparator 45 is input;
．． The reset terminal of the second counter 37.3g and the reset terminal of the first counter 37.3g.
The signals are respectively input to second inverter circuits 34 and 36.

47 is the third gate circuit, the first and second counters 37.3
8 and the comparator 45, only the comparator 45 is ``1''1''
When a signal is output, a “1” signal is output. Reference numeral 48 denotes a third counter which is set to a set state by the output signal of the third gate circuit 47, changes the clock pulse CP from 1 to 1, and outputs a signal of "1" and "1" when it counts up. 49 is a drive circuit,
It operates based on the output signal of the third counter 48 and drives the drive motor 50 of the aligning roller 20. 51.52 is the 1st. The second jam indicator indicates the first jam indicator. It is set (lit) by the output signal of the second counter 37°38, and the signal R1
It is reset (turned off) by . The output signals of the first to third counters 37, 38, and 48 and the comparator 45 are also sent to a main control section of the copying machine (not shown).

Next, the operation in such a configuration will be explained.

For example, when the paper feed cassette 14 is selected and a copying operation is started, signals 81 and 82 are output from the main control section. As a result, the first FF circuit 42 is set, the drive motor 44 is operated, the paper feeding roller 16 is driven, and the paper feeding operation is started. At the same time, the second AND circuit 35
1'' signal, and the second counter 38 starts counting clock pulses CP. The number of counts corresponding to the time required is set in advance.

Therefore, if the paper P is not detected by the detector 31 within the above-mentioned time, the second counter 38
The second jam indicator 52 is set and the paper jam from the paper feed cassette 14 is displayed. At the same time, the output signal of the second counter 38 is sent to the main control unit, which outputs the signal R2 to reset the second counter 38 and turn off the signal S1. Further, at this time, the first FF circuit 42 is reset by the output signal of the second counter 38, and the paper feed roller 16 is thereby stopped. In this case, jam processing is performed, and when the jam processing is completed, the main control section turns off the signal R2, and the copying operation becomes possible.

On the other hand, if the paper P is detected by the detector 31 within the above-mentioned time, then the first . Since the second counters 37 and 38 do not output the '1' signal and only the comparator 45 outputs the '1' signal, the third counter 48 receives the clock pulse C.
Start counting P. The output signal of the comparator 45 is simultaneously sent to the main control section, and the second counter 38 is reset by the output signal.

The third counter 48 is preset with a count number corresponding to the time required to convey the sheet from the point of the detector 31 to the aligning roller 20. However, the third
When the counter 48 counts up, the drive motor 50 operates according to the output signal, and the aligning roller 2
0 is driven and the paper P is sent out by the paper feed roller 16.
is transported to the image transfer section 21.

At the same time, the output signal of the third counter 48 is sent to the main control section, so that when the aligning roller 20 finishes feeding the paper, the main control section outputs the signal R3 and outputs the signal R3 to the third counter 48.
8 and then turns off the signal R2. Further, upon receiving the output signal of the third counter 48, the main control section turns off the signal S1, resets the first FF circuit 42, and stops the paper feed roller 16.

Note that when the paper feed cassette 15 is selected and a copying operation is started, the first AND circuit 33 and the first counter 37
The process is similar to that described above.

By the way, as described above, when a paper jam occurs, the copying operation is interrupted, but after the jam is cleared, the copying operation returns to the initial state. FIG. 3 is an example of a jam release circuit. In the figure, S4 is a signal that is constantly output from the main control section when the paper feed force cellars 1 to 14 are inserted, and S5 is a signal that is constantly output when the paper feed cassette 15 is inserted. 61 is the third AND circuit, and when the signal 32.84 is input, it becomes ""1"
Output a signal. 62 is a fourth AND circuit which receives signals S3.
When 85 is input, ``11'' outputs a signal. 63 is a NAND circuit, and the outputs of AND circuits 61 and 62 are both ``O''.
Outputs a signal and a 1-pair signal. A fifth AND circuit 64 outputs a "1" signal when each output signal of the NAND circuit 63 and the first OR circuit 39 is input. A third inverter circuit 65 inverts the output of the first OR circuit 39. 66 is the second FF circuit, and the fifth AND circuit 64
It is set by the output signal of the third inverter circuit 65, and reset by the output signal of the third inverter circuit 65.

67 is the fourth gate circuit, and the output of the NAND circuit 63 is II.
When the OII double signal, the set output signal of the second FF circuit 66 and the ON signal of the reset switch 68 are input, a "1" signal is output.The reset switch 68 is provided on the operation panel of the copying machine (not shown). ing.

In such a configuration, it is assumed that the second counter 38 has counted up and a paper jam has occurred from the paper feed cassette 14. The output signal of the second counter 38 sets the second jam indicator 52 to indicate a jam, and at the same time the first
The first F via the OR circuit 39 and the second gate circuit 41
The F circuit 42 is reset and the paper feed roller 16 is stopped. Further, the output signal of the first OR circuit 39 is input to the third inverter circuit 65, and the reset signal to the second FF circuit 66 is canceled. Here, when the user removes the paper feed cassette 14 to clear the jam, the third paper cassette 14 is removed. 4th AND circuit 6
Both outputs of 1.62 become the O11 signal, which causes the NAND circuit 63 to output the "'1" signal.Then, the fifth
The output of the AND circuit 64 becomes the "1" signal and the second FF
The circuit 66 is set, and its cellar 1~output is II I
II times signal. This state is maintained until the output of the first OR circuit 39 becomes the 11011 signal and is reset. After that, when the jammed paper P is removed by the user and the paper feed cassette 14 is inserted again, the output of the third AND circuit 61 becomes the "1" signal, so the output of the NAND circuit 63 becomes the 1101+ signal. Then, when the user turns on the glue set switch 68 to end the jam processing, the output of the fourth gate circuit 67 becomes a "1" signal, which becomes a jam release signal and is sent to the main control section. Then, the main control section outputs the signal R1 to reset the second jam indicator 52, and at the same time cancels the jam state and returns to the initial state.

Note that if a paper jam occurs from the paper feed cassette 15, the same process as described above is performed via the signals 33 and 35 and the fourth AND circuit 62.

As explained above, the detector 31 is provided near the aligning roller 20 on the conveyance path from the paper feed rollers 16 and 17 to the aligning roller 20.
By setting the paper conveyance time up to 1 to some extent larger than the actual time, it becomes possible to reliably detect a paper feeding error. Then, after the presence of the paper P is detected by the detector 31, by setting a timer (third counter 48) that sets the transport time to the alignment roller 20, the paper is transported from the paper feed rollers 1G and 17 to the alignment roller. Despite uncertainties in the conveyance time, such as time delays, the arrival time to the aligning roller 20 can be accurately determined, and therefore the aligning roller 2 is always optimal.
A driving start time of 0 can be set. This has a great effect in preventing poor conveyance of the aligning roller 20 to the image transfer section 21 and image deviation, and also enables quick processing in the event of paper feeding errors.

In the above embodiment, a case where the present invention is applied to a paper feeder in an electronic copying machine has been described, but the present invention can also be applied to this apparatus.

[Effects of the Invention] As detailed above, the present invention provides a paper feeding device in which the drive start time of the transport means can always be optimally set, and transport defects or paper feeding errors can be reliably prevented. can.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is a schematic longitudinal sectional front view of an electronic copying machine, Fig. 2 is a block diagram of a paper feed control circuit, and Fig. 3 is a block diagram of a jam release circuit. It is. 13...Paper feeding device, 14.15...Paper feeding cassette (
storage section), P... Paper, 16.17... Paper feeding roller (paper feeding means), 20... Aligning roller (conveying means), 21... Image transfer section (sheet feeding section), 31...
・Detector, Sl...Paper feed roller drive signal, 44...
Paper feed roller drive motor, 45... Comparator, 48...
Counter, 50... Aligning roller drive motor. Applicant's agent Patent attorney Takehiko Suzue

Claims (3)

[Claims] (1) A storage unit that stores paper, a paper feeding unit that feeds out the sheets in this storage unit one by one, a transport unit that transports the paper sent from the paper transport unit to the paper receiving unit, and a transport unit that transports the paper and the paper feed unit. a detector provided on a conveyance path between the paper feed means and the paper feed means for detecting the presence or absence of paper; a timer that starts operating when the detector detects the presence of paper after the paper feeding means starts operating; and the timer. a control means for operating the conveying means when a preset predetermined time has been measured. (2) The paper feeding device according to claim 1, characterized in that the operation of the paper feeding means is stopped when the conveying means is operated. (3) The paper feeding device according to claim 1, wherein the paper feeding section is an image transfer section for the number of copies.