JPH0154699B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a document feeding device that automatically feeds documents.

2. Description of the Related Art Conventionally, in a copying apparatus having an automatic document feeding function for automatically feeding a sheet-like document, it is common to start immediately with a paper feed signal that is generated when a document is set. Paper feeding will also start if you accidentally set the original at an angle, or if the original cannot be aligned when it is loaded, so it may damage the original, or if you pull out the original while trying to align it, it may become jammed. There were times when I was judged.

SUMMARY OF THE INVENTION An object of the present invention is to provide a document feeding device that eliminates the above-mentioned drawbacks. That is, a placing means 41 for placing the original, a feeding means 42 for feeding the original from the placing means to a predetermined position, an original detecting means 44 for detecting that the original is set on the placing means, and the above-mentioned A timer means 619 which starts a timer operation when the document detection means detects the document and delays the operation of the feeding means for a predetermined period of time, and means (FM) for operating the feeding means after the elapse of the predetermined time by the timer means. The present invention provides an original document feeding apparatus, further comprising: canceling the timer operation of the timer means (617) when the original is pulled out from the placing means within the predetermined time.

As a result, even if the document is pulled out, the feeding means does not operate idly, and a jam is not detected erroneously.

FIG. 1 is a sectional view of a copying apparatus to which the present invention can be applied.

The surface of the drum 11 is made of a three-layer photoconductor using a CdS photoconductor, is rotatably supported on a shaft 12, and starts rotating in the direction of an arrow 13 in response to a copy command.

When the drum 11 rotates to the normal position, the document placed on the document table glass 14 is illuminated by an illumination lamp 16 that is integrated with the first scanning mirror 15, and the reflected light is Scanning is performed by a first scanning mirror 15 and a second scanning mirror 17. 1st
The ratio of the scanning mirror 15 and the second scanning mirror 17 is 1:1/2.
By working at a speed ratio of , the document is scanned while the optical path length in front of the lens 18 is always kept constant.

The above reflected light image shows the lens 18 and the third mirror 19.
After passing through the fourth mirror 20, an image is formed on the drum 11 at the exposure section 21.

After the drum 11 is charged (for example, +) by a primary charger 22, an image irradiated by an illumination lamp 16 is slit-exposed in the exposure section 21.

At the same time, AC or primary charge removal with a polarity opposite to that of the primary charge (for example, -) is performed by a charge remover 23, and then a high-contrast electrostatic latent image is formed on the drum 11 by full-surface exposure using a full-surface exposure lamp 24.
The electrostatic latent image on the photosensitive drum 11 is then transferred to a developing device 25.
It is visualized as a toner image.

The transfer paper 27-1 or 27-2 is placed in the cassette 26-1 or 26-2 by the paper feed roller 28.
-1 or 28-2 into the machine, the first register roller 29-1 or 29-2 takes approximate timing, and the second register roller 30
The photosensitive drum 11 is sent out in the direction of the photosensitive drum 11 with accurate timing.

Next, while the transfer paper 27 passes between the transfer charger 31 and the drum 11, the toner image on the drum 11 is transferred onto the transfer paper.

After the transfer is completed, the transfer paper is guided to the conveyor belt 8, and then to a pair of fixing rollers 7-1 and 7-2, where it is fixed by pressure and heat, and then discharged onto the tray 6.

After the transfer, the surface of the drum 11 is cleaned by a cleaning device 5 composed of an elastic blade, and the process proceeds to the next cycle.

40 is an original automatic feeding device (hereinafter referred to as AF), 41 is a sheet bucket section for storing the original, 42 is a feeder section for separating and feeding the original, and 43 is for moving the original onto the exposure surface 14. This is the setter section to set.

The operation of the AF 40 shown in FIG. 1 will be briefly explained.

After storing the original in the bucket compartment and turning on the power of the copying machine, press the switch 92 of the AF operation unit to be described later and turn on the lamp inside the switch 92. The document is separated by a separation roller 61 and transferred to a feed roller 62.
lead to.

The roller 62 is operated at a predetermined timing for the time required to feed one sheet, and the document is fed to the belt 63 rotating on the document platen 14. The document caught on the belt 63 is fed at a predetermined timing until it reaches the claw 46, which is lowered, and is stopped there. The belt 63 rotates a little further and stops at a predetermined timing. The belt 63 slides on the document until it stops. Then, the lamp 16 and mirrors 15 and 17 of the copying machine start to move back and forth, and the original is scanned and exposed, and a copy is obtained on transfer paper as described above. When the number of copies set using a numeric key 87, which will be described later, is completed, a completion signal is sent to the AF 40, the pawl 46 is raised, the belt 63 is rotated again, and the original is ejected from the platen 14. Along with this discharge operation, the rollers 61 and 62 are operated to feed the next document toward the belt 63. In this manner, originals are exchanged one after another and copies are repeated. 44, 45, 47, 48 in AF40
44 is a detector for detecting the presence of a document; 44 is a detector for detecting whether a document is placed on the bucket section 41; and 45 is a detector for detecting whether the document is fed straight to the setter section 43. detector, 47
A detector 48 detects the document at the exposure position, and a detector 48 detects the ejection of the document.

The detectors 44, 45, 47, and 48 are of a reflection type using a plurality of light emitting diodes for one light receiving element, but may be of a transmission type. Further, the belt 63 is grounded to the main body in order to remove static charges that are generated and accumulated on the belt 63 when the document is held and conveyed.

Further, the AF 40 is set so as to be rotatable from the front side to the opposite side of the copying machine so that it can be separated from the platen 14. And the switch that automatically cancels AF operation when you move away from AF40 is AF.
40. This caused me to accidentally AF
40 is not activated.

FIG. 2 is a plan view of the operating section of the copying apparatus shown in FIG. 1. In the figure, 84 and 85 are keys for selecting the lower and upper cassettes, 86 is a slide lever for setting the copy density, and position 5 is the standard density. 87 is a numerical key for setting the number of copies, 88 is a clear key for canceling the number, 89 is an interrupt key for copying another number before the copying of the set number by key 87 is completed, 90 91 is a copy key for commanding the start of copying, and 91 is a stop key for stopping the copying operation during continuous copying of a set number. These keys use a flat type touch sensor, so they are extremely easy to operate. Become. The copy key will switch when pressed at 90±50g, and the other keys will switch when pressed at 120±50g, and return to normal when the pressure is removed.

71 to 76 are warning indicators from the main body, all of which are displayed as pictograms.

Reference numeral 71 is a paper feed check indicator that lights up when copy paper gets jammed inside the machine, when the original illumination lamp lights up abnormally, or when no signal is generated from the Hall IC under the optical mirror rail.

Reference numeral 72 lights up when there is no cassette in the cassette stand selected on the paper/cassette replenishment indicator, or when there is no paper left in the cassette set in that cassette stand.

Reference numeral 73 denotes a developer replenishment indicator, which lights up when the amount of developer in the developing device falls below a specified amount.

Reference numeral 74 is a serviceman call lamp that lights up when there is a failure that cannot be repaired by the user, prompting the user to call a serviceman.

Reference numeral 75 is a key counter check indicator that lights up when the key counter is not inserted into the socket of the main body. 76 is the wait/copying display. This display shows (1) When the power switch is turned on, if the temperature of the fixing heater is lower than the specified value, it will blink. (2) After pressing the copy start key, the final copy will be exposed. Since it stays lit until the end of the process, you can easily know when to replace the original.

Reference numeral 77 is a copy number set display, and when the desired number of copies is set using the numeric keypad, the set number of copies is displayed in seven segments. You can set 1 to 99 sheets at a time. The number of sheets set will automatically return to 01 when 30 seconds have passed after copying is completed or when the clear key is turned on. Reference numeral 79 is a copy number display which, when a copying operation starts, displays a count for each copy, and continues adding up and displaying the number until it matches the number of copies in the cassette.

Reference numeral 78 is an interrupt indicator that lights up when the interrupt key is pressed and goes out after the interrupt copy is completed.

Reference numerals 80 and 81 are upper and lower set size indicators that display the sizes of the cassettes set in both the upper and lower tiers. This display allows you to see the size of the upper and lower cassettes at the same time.

Reference numerals 82 and 83 display whichever key 85 or 84 is turned on (cassette stage).

FIG. 3 is a plan view of the AF operating section provided on the front surface of the AF 40. In the figure, reference numeral 92 is a self-illuminated switch, and when pressed when the main body and AF are available, the lamp 92' in the rear switch 92 lights up, and when pressed at other times, it does not light up. While lamp 92' is on
If the AF40 is not transporting an original, pressing the switch 92 will turn off the lamp 92, but while it is transporting the original, the lamp 92 will not turn off even if it is pressed. 93 is a self-illuminated stop button for making an emergency stop while the AF40 is transporting the original, and 93' is a lamp that indicates that a stop signal has been input.

Reference numeral 94 denotes a conveyance abnormality display lamp that lights up when a conveyance abnormality such as a jam occurs during original conveyance.

The operation of the AF 40 will be explained in detail with reference to FIG. A signal indicating whether or not the main body is capable of copying is input from the main body of the copying apparatus to the AF40.

The main unit can be copied and AF40 is in the specified state,
In other words, when the original is ready to be sent,
The switch 92 is in an acceptable state,
The lamp 9 inside the switch 92 indicates that the AF40 is ready for use when the switch 92 is pressed.
2' lights up.

If the main unit of the copying machine is not turned on when the switch 92 is pressed, or if there is no paper in the specified cassette, or if the main unit is
If the main body of the copying apparatus is not ready for copying due to time or other reasons, no matter how much the switch 92 is pressed, the lamp 92' will not light up and the AF 40 will not function, that is, the AF will not be ready for use. Also, AF4
Even on the 0 side, if the original placed in the setter section is off the exposure surface, and if the original cannot be conveyed correctly when the AF 40 starts to operate, the AF will not become usable and the switch 92 will not be able to use the original. The lamp does not light up. The AF
Even when the conveyance abnormality display lamp 94 is lit in step 40, the above-mentioned AF function state is not entered. This allows the user to
Since 2' does not light up, you can quickly check for easily overlooked areas such as empty cassettes. In other words, the above switch 92 is AF
40 is in a usable state and the main body is in a usable state, it becomes acceptable and the lamp 92' lights up.

As an exception, the time required for the main unit to heat the fuser, etc. from power-on to standby is determined by switch 9.
2 becomes ready to be accepted, the lamp 92' lights up, and when the original is set in the bucket section, the AF 40 starts at the same time as the main body goes into standby, and the copying operation is performed.

In addition, when the lamp 92' is turned on at the initial stage, if the original is not set in either the exposure position or the sheet bucket part 41, a first timer for counting a first predetermined time after the switch 92 is pressed is activated. During this time, the lamp in the switch 92 continues to light up, and if the original is set in the seat bucket compartment 41 before the first predetermined time elapses, the first timer is canceled and the second predetermined time starts. The set timer that measures time starts working again. When the set timer expires, the rollers 61 and 6 of AF40 are activated.
When the copying operations for all set originals are completed, the first timer starts counting again.

Furthermore, if the document is removed from the bucket section 41 before the set timer finishes counting the second predetermined time, the set timer is canceled and the first document is read again.
The timer starts counting.

If the original is not set in the bucket part 41 within the first predetermined time, the switch 9
The lamp inside 2 goes out and the usable state of the AF40 is released. Also, forgetting that the lamp in the switch 92 is on, the setter section 43 is turned off from the platen 14.
Even when the driver moves away from the switch 92, the lamp in the switch 92 goes out and the rollers 61, 62 and belt 63 do not operate.

In other words, even if the lamp in the switch 92 is turned on and the AF 40 is ready to feed when an original is set in the storage section (bucket section), if the original is not set, the switch 92 will automatically Since the lamp is turned off, not only can power consumption be reduced, but even if the next user accidentally places the original in the storage section, there will be no malfunction, so the original will not be damaged.

Furthermore, since the originals can be fed at any time during the first predetermined time, there is no need to set all the originals in the bucket section 41, which serves as a paper feeding section for storing originals, before issuing a copy start command.

In addition, the set timer operates after the original is set, and the rollers 61, 62 and belt 63 are not driven during the second predetermined time (approximately 2 to 4 seconds), so if the original is set diagonally, the original Since there is time to reset the original, it is possible to prevent the original from being transported abnormally and to prevent the original from being damaged.

Also, after all AF40 copies have been completed and the first predetermined period of time (approximately 20 seconds to 1 minute) has elapsed, the AF40 usable state is automatically canceled, so it can be used for normal copying of thick originals later. It does not cause any trouble to anyone.

Circuit diagrams of a copying machine having the above-mentioned functions are shown in FIGS. 4 and 5.

In the figure, the signal CPE is a cassette paper presence signal indicating that there is paper in the cassette, SCL is a serviceman call lamp non-lighting signal, JAM1 is a main body jam no signal, and SCS is a signal in which the setter section 43 is located above the platen 14. A signal indicating that JAM2 is AF4
There is no jam signal on the 0 side, WAIT is the turn-off signal of the wait lamp 76 indicating that the main unit is ready, POC is the original detection signal of the exposure position on the platen 14, POS is the original detection signal of the bucket part 41, OK1 is AFSP is an AF stop signal that is output when the stop key 93 on the operation panel of the AF40 is pressed, and CPSP is a copy end signal that indicates that a predetermined number of copies have been made for one original. AFED is the original discharge confirmation signal that is output when the original is discharged from the setter section 43, FM is the feeder drive signal that drives the rollers 61 and 62 of the feeder section 42 of AF40, and SM is a setter part drive signal that drives the belt 63 on the setter part 43 side, PSP is a plunger drive signal that drives a plunger to remove the pawl 46 that stops the original from the conveyance path, and PSS is a plunger drive signal that stops the roller 63 and starts copying. Copy start signal, AFOK is skew detection detector 4
5 is a detection signal indicating a state in which light from the optical system of the document exposure lamp 16 is being detected.

When the signals CPE, SCL, and JAM1 are all at a high level (hereinafter referred to as "H"), the output of the AND gate 600 becomes "H". In other words, when there is no abnormality on the main body side, the output of the AND gate 600 becomes "H".

Further, when the signals SCS and JAM2 are both "H", the AND gate 604 becomes "H", indicating that there is no abnormality in the AF main body. 612 is the switch 92
is displayed, and when the switch is pressed when there is no abnormality with the main body AF, the RS flip-flop (hereinafter referred to as FF) 60
9 is in the set state. On the other hand, since the FF 608 is not set at this point, its output is low level (hereinafter "L"), so the output of the exclusive OR gate 632 goes "H", turning on the transistor 631 and lighting the lamp 610. lamp 61
0 is a lamp in the switch 92 that indicates an AF enabled state.

At this time, when the switch 612 is further pressed, both the inputs of the AND gate 603 become "H" due to the output of the inverter 611, so the FF 608 is set.
Since the output of the FF 608 becomes "H", the output of the gate 609 becomes "L" and the lamp 610 goes out. Further, while the lamp 610 is on, either there is no paper in the cassette and the CPE becomes "L", or the serviceman call lamp lights up and the SCL becomes "L", or the setter section 43 is separated from the top of the platen 14 and the SCS becomes "L". When it becomes "L", the FF 609 is reset, so the output of the gate 632 becomes "L" and the lamp 610 goes out.

Further, when the lamp 610 is on and there is no document at either the exposure position or the feeder section, the output of the AND gate 623 becomes "H", the FF 617 is set, the first timer 618 is set, and the first predetermined time is set. to measure the time. The first timer 6
If paper is set in the feeder section while 18 is timing,
Both the FF 617 and the first timer 618 are reset, and the timer 619, which is the set timer, is set. When the set timer 619 becomes "L" after counting the second predetermined time, the output of the timer 618 is also "L", so the output of the NOR gate 622 becomes "H", and since the document is set in the feeder section 43 at this time, the AND gate 626 The output of is “H”, the terminal is “H”, and both FM and SM are “H”
As a result, the AF40 roller is driven.

Furthermore, when the first timer 618 finishes counting, the output of the timer 618 becomes "L" and at this time, the output of the set timer 619 also becomes "L", so the output of the NOR gate 622 becomes "H", but the signal POS
is "L", the output of the AND gate 626 becomes "L", and the roller of AF40 is not driven. At this time, the output of the AND gate 634 becomes "H", and the FF 609 is reset, and the lamp 610 is reset.
Turn off the light.

Further, after the set timer 619 is set, the feeder section 42 is
When the document is taken from the document, the FF 617 is set again, so the first timer 618 is set,
The second timer is reset and measures the first predetermined time again.

When all the originals set in the feeder section 42 have been copied and the last original is discharged, the signal POS becomes "L" and OK1 and AFFD become "H", so the output of the AND gate 645 becomes "H". The first timer is set again to measure the first predetermined time.

Further, in the copying apparatus of this embodiment, when starting copying after setting the AF 40 to a usable state, if the original is in the bucket part 41, the original is fed to the exposure position and copied, and the original is placed on the original platen 14. When in the exposure position, a copy is made of the original on the platen. In other words, the device does not choose the placement position of the document, and after confirming the placement position, it enters a state suitable for each operation. For example, if an original is set on the exposure surface but no original is set on the sheet bucket part 41, the detector 47 detects the original on the exposure surface and performs a copying operation on the original on the exposure surface. When the process is completed, the original is ejected. At this time, if an original is set in the sheet bucket part 41, after the copying operation is completed, the original in the sheet bucket part 41 is sent to the setter part 43 at the same time as being ejected.

In other words, if an original is already set at the exposure position when a command to start copying is given, the presence of the original is detected by the detection means, the copying operation is started, and after a predetermined number of copies have been made, the original set at the exposure position is fed. It is discharged by means AF.

Further, when the original is not placed at the exposure position but only on the sheet bucket part 41, the original is immediately sent to the exposure position. Further, when the original is set at the exposure position, a copying operation is performed, and when the copying operation is completed, the original is ejected,
An operation is performed to feed a new original to the exposure position, and the above operation is repeated until there are no more originals in the sheet bucket part 41.

With this configuration, it is possible to make copies whether the original is placed in the bucket where originals are stored or placed in the exposure position.
It is very easy to use even for users who are not familiar with AF.

If a document feeding error occurs while the rollers 61, 62 and belt 63 of AF40 are being driven, the rollers 61, 62 and belt 6 should be removed to protect the original.
3 all stop, and the indicator lamp 94 lights up. At this time, the lamp 92' in the switch 92
continues to light up and AF40 remains usable.
At this time, even if the setter section is separated from the platen 14 in order to cancel the conveyance abnormality, the lamp in the switch 92 continues to be lit. For this reason, after resetting the document with the conveyance error and pressing the reset button provided inside the AF 40 to cancel the conveyance error, the display lamp 94 goes out and the setter section 43 is returned to the predetermined position, without pressing the switch 92 again. The rollers 62, 62 and belt 63 are driven to perform the AF40 operation. In this case, the original set position after the conveyance error may be placed at the exposure position on the platen 14 or may be placed on the bucket part 41.
Furthermore, even if a jam occurs in the main body, a paper out of the cassette, etc. occurs in the main body while the lamp in the switch 92 of the AF 40 is lit, and copying becomes impossible, the AF 40 remains usable as long as the switch 92 is not pressed. When the copying operation of the main body becomes possible, the operation of the AF 40 is started.

In addition, the stop key 9 on the operation section of the main body of the copying machine
When 1 is pressed, the main unit stops after ejecting the copy that was made when the stop key 91 was pressed, and the AF4
On the 0 side, when the stop key 91 is pressed, only the original located at the exposure position on the platen 14 is discharged, and the original located in the bucket part 41 is not transported. When the original at the exposure position is ejected, the lamp in the switch 92 is turned off and the usable state of the AF 40 is released.

In other words, the copying apparatus of this embodiment includes the AF 40 as a feeding means for feeding an original to an exposure position, the apparatus main body as an image forming means for forming a copied image,
A stop key 91 on the main body side is provided as a command means for commanding to interrupt the operation while the image forming means is in operation, and since the original at the exposure position is ejected according to the command from the command means, the user can stop image formation. It is very simple because the original at the exposure position can be ejected just by commanding.

As mentioned above, the lamp 92' inside the switch 92 is
Lights up when AF40 is ready for use and when AF40 is in use. Lighting means that AF40 is in a position where it can be fed, and when the copying machine and AF40 are operational and a document is set, feeding will occur. It means to do. Therefore, if any abnormality occurs while the lamp in the switch 92 is lit, the user must remove the abnormality and the AF 40 will start operating again, so the user must press the copy button again or turn off the AF power supply. There is no need to perform extra operations such as re-inserting the .

Also, if you press the stop button 93 on the AF40 side,
When the lamp 93' is lit and the rollers 61, 62 or the belt 63 are being driven, the rollers 61, 6
2. All the belts 63 are stopped and the lamp 9 is turned on to indicate that a stop signal has been input.
3' goes out and the AF usable state is reset.

In this embodiment, the motor that drives the setter belt 63 and the motor that drives the feeder rollers 61 and 62 are separately provided, but it is also possible to use a single drive source by switching them using a clutch or the like. .

The above functions will be further explained using FIGS. 4 and 5.

When the lamp 610 is lit, the output of the inverter 611 is "H" and the signal from the main body is
When WAIT is "L", the output of AND gate 613 is "L", and when WAIT is "H", the output of AND gate 613 is "H". At this point, if the original is set at the exposure position (POC is "H") and the copy end signal OK1 is "L", the output of the AND gate 614 becomes "H" and the copying operation of the main body is started by the signal PSS. While the lamp 610 is on, the signal
When OK1 is “H” or there is no original at the exposure position (POC is “L”) and there is paper in the feeder section (POS is “H”), the output of the AND gate 616 is “H” or “H” Therefore, as shown in Fig. 5, the signal SM becomes "H" and the setter belt 6
3 is driven, the signal PSP becomes "H" and the pawl 46 on the conveyance path is removed.

At this time, when there is no original at the exposure position (POC is "L"), the optical system is not being driven, so the signal FM also becomes "H" and the setter belt 63 and toffee rollers 61 and 62 are driven almost simultaneously. However, when the final exposure is completed for the document at the exposure position (when OK1 becomes "H"), the original skew detection detector 45 shown in FIG. The afterglow after the light is reversed and turned off is detected, and the signal AFOK is set to "L" to prohibit the feeder rollers 61 and 62 from being driven while the afterglow is being detected. The reversal position of the optical system differs depending on the original size, so the larger the size, the more AFOK will be "L" from the time of reversal (when OK1 becomes "H").
Because the exposure time is long, it is possible to feed the exposed original with a sufficient interval between the next original to be fed, and the next original can be fed before the exposed original is completely ejected. It is possible to prevent the occurrence of jams, and to increase the copy speed by minimizing the distance between originals.

Next, when the signal OK1 becomes "H" and there is no paper in the feeder section 42 (POS is "L"), the output of the AND gate 633 becomes "H" and becomes "H".

As shown in FIG. 6, when the signal becomes "H", SM becomes "H" and FM becomes "L", and the setter belt 63 is driven to eject the original at the exposure position.

Also, during copying, the copy stop signal on the main unit
When CPSP is output, a signal indicating the reversal of the optical system
When OK1 becomes "H", the output of the AND gate 629 becomes "H" and the terminal becomes "H", so only the setter side belt 63 rotates, and when the original in the setter section is ejected, the signal AFED goes "H". ”, and the output of the AND gate 640 becomes “H”, so
The lamp 610 is turned off, and the setter side belt 6
3 stops.

When FM or SM is "H" and the AF side stop button 93 is pressed, AFSP becomes "H", the lamp 610 goes out, and the AF side stop button 93 is pressed.
The inner lamp 627 lights up and all roller driving stops.

Although this embodiment has been described using a transfer-side copying device, it is also applicable to a type of copying machine that directly forms an image on photosensitive paper. Furthermore, in this embodiment, the feeding means is explained using a type in which feeding of the document is stopped at the exposure position and the document is ejected after the scanning of the optical system is completed, but the document is scanned while the optical system is stopped. The present invention can also be applied to a copying apparatus using a type of automatic document feeding means.

As described above, the document feeding apparatus of the present invention has various effects such as improved copying speed, improved operability, and prevention of jamming.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the copying apparatus of this embodiment, FIG. 2 is a plan view of the operating section of the copying apparatus shown in FIG. 1, FIG. 3 is a plan view of the operating section of the original automatic feeding device, and FIG.
FIG. 5 is a control circuit diagram of the original automatic feeding device. In the figure, 40 is the original automatic feeding device;
45 is a skew detector, 61 is an original separation roller, 62 is a feed roller, 63 is a feeding belt,
Reference numeral 91 indicates a main body stop key, and reference numeral 92 indicates a switch for enabling AF.

Claims (1)

[Scope of Claims] 1. Placing means for placing a document; Feeding means for feeding the document from the placing means to a predetermined position; Document detecting means for detecting that the document is set on the placing means. , timer means for starting a timer operation when the document detecting means detects a document and delaying the operation of the feeding means for a predetermined period of time, and means for operating the feeding means after the elapse of the predetermined time by the timer means. . A document feeding device further characterized in that when the document is pulled out from the placement device within the predetermined time, the timer operation of the timer device is canceled.