JPS6016621B2 - Automatic document feeder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic document feeder used in a copying machine.

Generally, in an automatic document feeder, as shown in FIGS.
When the original is inserted from the document insertion table 5 through between the belt 1 and the pinch roller 6 and between the belt 1 and the guide plate 7 to the stopper 8, the detection means 27 using the micro switch 9 detects the Detect the original.

In the copying machine main body 10, if all prohibition conditions such as no paper in the paper feed section, a transfer paper jam, copying, etc. are not satisfied, the gate 11 is opened, and the signal from the detection means 27 passes through the gate 11 to the delay circuit 12. added to. Delay circuit 12
is a certain period of time from when the microswitch 9 detects the leading edge of the document, for example 0. After Sec, a start signal is output, and this start signal is applied to the main body of the copying machine as a print signal to enter the copy mode. At the same time, the start signal from the delay circuit 12 turns on the inlet solenoid 13 to retract the stopper 8 and pull the pinch roller 6 toward the belt 1 side. Further, the drive motor 14 is turned on by applying the start signal from the delay circuit 12 through the OR circuit 15, and drives the belt. For this purpose, the original is conveyed by the belt 1, guided by the guide plate 7, guided onto the original table 16 of the main body 10 of the copying machine, and stopped at the exposure position by the stopper 17. Also, the timer 18 is triggered by the start signal from the delay circuit 12, and the motor 1
4 is reset by applying the output signal of the timer 18 through the OR circuit 19. The inlet solenoid 13 is turned off by the signal from the detection means 27 when the microswitch 9 detects the trailing edge of the document, and at the same time the stopper 8 is returned to the operating position and the pinch roller 6 is turned off.
evacuate. Thereafter, at the end of exposure or copying of the original set on the document table 16 in the copying machine main body 10, an ejection signal is generated, and this ejection signal is sent to the exit solenoid 2.
0 is turned on to retract the stopper 17 and pull the pinch roller 21 toward the belt. Further, the motor 14 is turned on by applying the discharge signal through the OR circuit 15.
Drive the belt. Therefore, the original is conveyed by the belt 1, guided by the guide plates 22 and 23, and then transferred to the feed roller pair 2.
A detection means 28 using a microswitch 26 detects the trailing edge of the document near the feed roller pair 24, and the exit solenoid 20 is turned off by the output signal of the detection means 28. and motor 14
is turned off by applying the output signal of the detection means 28 through the OR circuit 19. Further, as shown in FIG. 3, this automatic document feeder 29 is pivotally supported by the main body 10' of the copying machine, and is provided with a safety switch 30 at the bottom. When copying a standard document 31 such as a stapled document, a non-standard thin document, or a thick document, the automatic document feeder 29 is set in a raised position above the document table 16. The safety switch 30 is turned off and the control circuit shown in FIG. 2 is reset so that it does not operate, and the document 31 is manually set on the document table 16 and the print switch on the copying machine body 10 is pressed. Copying is performed. When copying a passable document, the safety switch 30 of the automatic document feeder 29 is turned on by being pressed on the top surface of the copying machine main body 10, and the automatic document feeder 29 operates as described above. However, in such an automatic document feeder, if the safety switch 30 is turned on even though it is not used, that is, if it is used instead of a pressure plate when copying a document 31 that can be passed through, the document will not be inserted. At the start, the belt 1 does not move and there is no problem, but at the end of exposure or copying, the main body of the copier 1
The ejection signal is input from 0, the belt 1 moves, and the original 31
Trying to forcefully eject the paper often causes problems such as jams and scratches. SUMMARY OF THE INVENTION It is an object of the present invention to provide an automatic document feeder which eliminates the above-mentioned drawbacks and does not cause any trouble even when used in place of a pressure plate.

Embodiments of the present invention will be described below with reference to the drawings.

This embodiment stores whether a start signal is generated,
The document ejecting operation is not performed when the start signal is not generated.

Specifically, in the automatic document feeder described above, a broken line circuit A is added to the control circuit as shown in FIG. When a start signal is output from delay circuit 12, flip-flop 32 is set by the start signal. That is, when the automatic document feeder and the copying machine main body 10 start operating due to insertion of a document into the automatic document feeder, a start signal is always generated and the flip-flop 32 is set. At the end of exposure or copying, an ejection signal is sent from the copying machine main body 10, and this ejection signal is ANDed with the output signal of the flip-flop 32 in an AND circuit 33. The ejection signal from the AND circuit 33 is applied to the exit solenoid 20' and simultaneously applied to the motor 14 through the OR circuit 15 to eject the document as described above. reset by . If the start signal is not generated, even if an ejection signal is subsequently sent from the copying machine main body 10, this ejection signal is blocked by the AND circuit 33 and is made invalid. Therefore, even if it is used instead of a pressure plate when copying a document 31 that cannot be passed through, the document ejection operation is not performed, and troubles such as jams and scratches do not occur. As described above, in the automatic document feeder according to the present invention, the flip-flop is set by the start signal, and only when this flip-flop is set, the document is ejected by the ejection signal from the copying machine main body, and the flip-flop is reset. So,
When used in place of a pressure plate, troubles such as jamming and scratching of the original do not occur because the document ejection operation is not performed, and operability can be improved by being used in place of the pressure plate.

[Brief explanation of the drawing]

FIG. 1 is a schematic front view showing a conventional automatic document feeder;
FIG. 2 is a block diagram showing the control circuit of the device, FIG. 3 is a front view showing the device in an inconvenient state, and FIG. 4 is a block diagram showing the control circuit in an embodiment of the present invention. 32...Flip-flop, 33...AND circuit. "Rare" figure silk 2 figures 3 and 4 figures

Claims (1)

[Claims] 1. In an automatic document feeder that starts a document setting operation in response to a start signal and puts the copier main body into a copy mode, and ejects the document in response to an ejection signal from the copy machine main body, the document feeder is set by the start signal. An automatic document feeder comprising a flip-flop, and means for validating the ejection signal only when the flip-flop is set so that the ejecting signal causes the original to be ejected and resetting the flip-flop.