JPH0336742B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a paper feeding device that picks up and conveys sheets of paper one by one from a paper storage section.

[Prior Art] Conventionally, an image forming apparatus such as a copying machine generally uses a paper cassette insertion method to feed paper.

However, the storage capacity of the paper cassette is 250 sheets.
It holds about 500 sheets, and if you want to copy a large number of sheets, such as 1000 or 2000 sheets, in succession, you will have to replenish the paper in the cassette many times during the process.

Therefore, a paper feed device having a deck mechanism capable of storing, for example, about 2000 sheets of paper at a time is attached to the image forming apparatus.

In such a paper feeding device, when a sheet of paper waiting in the paper transport section of the paper feeding device is fed by the operation of the paper feeding means on the image forming device side, the next sheet is transferred from the paper storage section of the paper feeding device. One sheet of paper is fed out, conveyed to a predetermined position in the paper conveyance section, and placed on standby.

[Problems to be Solved by the Invention] However, when the paper sizes to be fed differ, the transport loads on the paper differ.

In other words, when transporting small-sized paper, the trailing edge of the paper fed from the storage section slips out from under the paper feed roller during transport, and transport continues with a small transport load until the transport stops. reach.

However, when large-sized paper is being transported, the trailing edge does not come out from under the paper feed roller, and in other words, the transport is stopped when the transport load is large. Furthermore, if the size of the paper is large, the contact friction between the paper transport section and the paper will be large, and the transport load will be large.

That is, in the case of small-sized paper, the transport load when the transport is stopped is light, and in the case of large-sized paper, it is heavy. Therefore, if the driving of the conveying means is always stopped at the same timing regardless of the paper size, the stopping position will differ depending on the difference in the conveying load.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a storage section 1 that stores a plurality of sheets, and a size detection means 8 that detects the size of the sheets stored in the storage section.
31, a paper feeding means 21 for feeding the paper stored in the storage section, and transport means 27 and 4 for transporting the paper fed by the paper feeding means along the transport path.
2, a detection means 807 provided on the conveyance path for detecting paper, a counting means 802 for counting pulses, and a detection means 807 provided on the conveyance path to temporarily stop the paper at a common predetermined position regardless of the paper size on the conveyance path. control means 801 that stops the operation of the conveying means when the counting means counts a predetermined number of pulses after the detection means detects the paper;
and the control means changes the predetermined number depending on the paper size detected by the size detection means.

[Function] With the above-described configuration, the present invention allows sheets to be accurately stopped at a common predetermined position regardless of the sheet size.

〔Example〕

This embodiment shows a paper feeding device that feeds paper to a paper processing device. The external appearance and configuration diagram of the paper feeding device of this embodiment are shown in FIGS. 1 to 4, and a partially enlarged view is shown in FIG. 5. Also, a detailed diagram of the main control section is shown in Figure 6, and the lifter motor
A detailed diagram of the M1 control section is shown in FIG. 7, and its timing chart is shown in FIG. 8. In addition, the control unit of this embodiment
CPU control flowcharts are shown in FIGS. 9 to 11.

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

General configuration, usage, and functions of this embodiment.

The paper feeding device of this embodiment can be broadly divided into, for example:
Large-capacity paper storage section (hereinafter referred to as the lifter section) that can load and store 2000 cut sheets at once.
and a conveyance section that takes out and conveys sheets of paper one by one from the lifter section and holds the conveyed sheets.

The lifter section incorporates an elevating paper storage mechanism (lifter mechanism), a paper feeding mechanism for each sheet of paper, and a control circuit.

In the lifter mechanism, 13a and 13b are channel rails each having a substantially U-shaped cross section and vertically arranged opposite to the side cover; 1 is a middle plate serving as a paper storage stand; A pair of upper and lower rollers 12a and 12b are pivotally mounted. and a vertical channel rail 13a with one pair of rollers on each left and right side arranged inside the side cover,
It is fitted and engaged in the groove of 13b. Therefore, the middle plate 1 can freely move up and down along the rails 13a and 13b. 853 is a lifter motor M1 attached and held at the bottom of the lifter part.
A sprocket 4 is fixed to the drive shaft of M1853. Further, the lifter middle plate 1 is latched and connected to vertical chains 11a and 11b, and the chains 11a and 11b are rotary shafts disposed with bearings on side covers, and sprockets 7a and 7a fixed to both ends of 8 and 9, respectively. 7b (not shown) and 10a, 10
It is suspended between b. The lower rotating shaft 8 projects outside the side cover, and a sprocket 6 is attached to the projecting shaft via a one-way clutch 6a. A chain 5 is suspended between this sprocket 6 and the sprocket 4, and the rotational force of the lifter motor M1853 is transmitted to the lower rotating shaft 8 via the sprocket 4 → chain 5 → sprocket 6 → one-way clutch 6a. Left and right vertical chains 11a and 11b move up and down the lifter middle plate 1 via sprockets 7a and 7b (not shown) fixed to the rotating shaft 8.

Reference numeral 813 in FIG. 3 is a holding solenoid equipped with a pawl plate that is biased in the direction of engagement with a stopper ratchet gear fixed to the rear end of the rotary shaft of the lifter motor M1853, and the suction action of this solenoid causes the pawl plate to It is separated from the ratchet gear to allow rotation of the motor rotation shaft. Holding solenoid 813
When the lifter motor M1853 is in a non-suction state, the pawl plate engages with the ratchet gear and prevents the rotating shaft of the lifter motor M1853 from idling. This prevents the middle plate 1 in the lifted position from sliding down due to the self-gravity of the paper stacked on it, causing the rotary shaft of the lifter motor M1853 to idle, and keeps the middle plate 1 in the lifted position stably. be done.

Reference numeral 14 denotes a paper sensor lever rotatably supported by a bearing on a side plate, the details of which are shown in FIG.
The downward protrusion 14c of the arm of the sensor lever 14 normally contacts the upper surface of the stacked sheets on the intermediate plate 1, and detects that the sheets are within a predetermined position level range PH to PL. A limiter switch 854 is located opposite the upward protrusion 14a at the base of the arm of the sensor lever 14, and is used to detect that the rise of the intermediate plate 1 exceeds a permissible range. In addition, near the bearing holding part of the sensor lever 14, there is a protrusion for blocking the optical path of the UP level sensor 809 for detecting the uppermost position of the paper, so that the upper surface of the paper is in a predetermined position level range.
The lowest position PL from PH to PL is monitored.

When the stacked sheets on the intermediate plate 1 are sequentially fed out one by one from the top by the operation of a paper feeding mechanism to be described later, the upper surface position of the stacked sheets gradually lowers. Following this, the sensor lever 14 gradually tilts and rotates. When the upper surface position of the paper reaches the lower limit level (PL), the optical path of the UP level sensor 809 becomes open, and it is detected that the upper surface position of the paper has fallen to the lower limit level. Based on this signal, the holding solenoid is driven via the control circuit, and then the aforementioned lifter motor M1853 is driven for a certain period of time to raise the middle plate 1 and return the paper top surface position to the allowable upper limit position PH. As the stack of sheets continues to be consumed, the intermediate plate 1 also rises intermittently, and when the last sheet on the intermediate plate 1 is fed, the downward protrusion 14c of the sensor lever 14 The sensor lever 14 falls into the through hole 1a formed at the surface corresponding to the protrusion, and the tip of the other downward protrusion 14b contacts the intermediate plate 1, and the optical path of the UP level sensor 809 becomes open. At this time, the paperless switch 805 is already activated by the cam 100 attached to the middle plate 1. Here, the paperless switch 805 is lower than the height when there is only one sheet of paper on the middle board 1, and the height of the middle board 1 at which the paperless switch 805 is detected is lower than the height when there is only one sheet of paper on the middle board 1. It operates within a height range where the optical path of the level sensor 809 is closed by paper. This paperless switch 805 signal and UP level sensor 80
No paper is loaded on the intermediate plate 1 by the 9 signal.

Next, the transport section will be explained in detail. The transport unit is driven by a transport motor M281 mounted and held at the bottom of the chassis.
5. A sprocket 16 is fixed to the drive shaft of the transport motor M2815.
In addition, a timing pulley 18, a gear 18b, and a clock disk 1 are mounted on the pin shaft installed on the upper part of the chassis side plate.
A timing belt 17 is suspended between the sprocket 16 and the timing pulley 18.

Reference numeral 21 denotes a paper feed drive shaft rotatably disposed on the upper part of the chassis side plate, and a paper feed sprocket 20a is attached to the drive shaft via a one-turn clutch 20. The paper feed sprocket 20a is meshed with the sprocket 18b. As a result, the rotational force of the conveyance motor M2815 is transmitted to the pulley 16, the timing belt 17, and the pulley 18, and the three-member pulley 18, sprocket 18b, and clock disk 18a are rotationally driven together with the paper feed drive shaft 21. In this case, when the outer ring of the one-turn clutch 20 is ejected by the pawl arm whose swing is controlled by the paper feed solenoid 811, the connection with the paper feed drive shaft 21 is released, and the sprocket 20
The rotation of a is not transmitted to the paper feed drive shaft 21. In this case, when the paper feed solenoid is sucked and the outer ring of the one-turn clutch 20 by the pawl arm is released, the clutch 20 becomes connected to the paper feed drive shaft 21 and rotates the paper feed drive shaft.

Further, the sprocket 18b is meshed with a sprocket 19 mounted on a shaft rotatably supported on the side surface of the chassis.
Similarly, the sprocket 31 is engaged with a sprocket 31 which is mounted via a one-way clutch 31a on a shaft rotatably supported on the side of the chassis. The one-way clutch 31a is a conveyor solenoid 812
It is latched by a claw arm that is swing-controlled. When the conveying solenoid 812 is driven and in the suction state, the sprocket 31 is kept uncoupled from the shaft, and the sprocket 31 is idly rotating on the shaft. When the conveyance solenoid 812 is in the non-suction state, the pawl arm escapes from the one-way clutch 31a, the shaft and sprocket are connected, and the shaft is driven to rotate. A sprocket 32 is also mounted on this shaft, and the rotation of the sprocket 32 is transmitted via an idler 32a to a sprocket 33 mounted on the shaft on which the transport roller 27 is mounted, causing the transport roller 27 to rotate. Further, this rotational force rotationally drives a conveyance roller 42a at the tip of the conveyance section via the timing belt 40.

There is a paper size support cam 46 at the tip of the conveyance section.
The paper size detection switch 831 is driven by the rotation of 46a provided exposed on the outer surface of the chassis board, and the set paper size is detected.

FIG. 7 is a circuit diagram of the main control section 801.
Reference numeral 2 denotes a control unit CPU, and the CPU 802 receives sensor signals from various sensor units and signal outputs from the drive system.

The operation of this embodiment will be described below with reference to a control flowchart.

When the power to the paper feeder is turned on, the CPU in the main control unit
If the door switch 852 or joint switch 803 is open, 802 executes the lifter lowering control program DCTL, which will be described later, at step 1006.
(from step 1070). This is the case when the paper cover is opened to set paper or when the paper feeder is not connected to the paper handling device.

Next, set the paper on the middle plate 1 and close the cover. When the cover is closed, the door switch 852 moves from the b position shown in FIG. 7 to the a position, and +24V power is supplied to the lifter motor M1 upward drive circuit.
The lifter motor M1853 can be driven upward and the transport motor M2815 can be driven. At the same time, a door switch signal is sent via the receiver 817.
It is input to the CPU 802. Next, the joint switch 803 is activated by connecting the paper feeding device to the recording apparatus main body, and this signal is input to the control unit CPU 802 via the receiver 817. control part
In the CPU 802, when the joint switch signal is input, the lifter motor M1853 is controlled in the upward control flow UCTL until the UP level sensor 809 is activated.
The middle plate 1 is raised according to the steps (from step 1090). In the upward control flow UCTL, if the intermediate plate 1 is descending (step 1091-Y), the lower side of the intermediate plate 1 is stopped by the lowering stop program (step 1083 and subsequent steps). If middle plate 1 is not descending (step
1091-N) raises the middle plate 1 until the UP level sensor 809 or paperless switch 805 is activated. To raise the middle plate 1, use the holding solenoid
Drives SL3813, lifter motor M1853
The lock is released (step 1095), and after an arbitrary period of time (for example, 150ms) has elapsed (step 1098).
The lifter motor M1853 is driven to set the lift mode (step 1100). Lifter motor M1
853 is driven by driver 827 from CPU 802.
and M1BK/ON output via 828 and
This is done by the M1DWN/UP signal.

Now to the lifter motor M1 control section 851.
When the M1BK/ON signal M1ON (LOW level) is input, the receiver 855G output becomes HIGH, the outputs of the brake drive ICs 855c and 855f become LOW level, the brake drive transistors 868 and 879 turn OFF, and the brake of motor M1 is released. be done. At this time, M1DWN/UP
When the signal is UP (LOW level), lower drive IC85
5e output becomes HIGH, and the output of the rising drive IC 855b becomes LOW after the time set by the time constant of the resistor 858 and capacitor 859 has elapsed, the rising drive transistor 864 turns on, and +24V is applied to the X of the motor M1 via the transistor 863. At the same time, transistor 881 and transistor 86
4 and resistor 873. As a result, current flows through the lifter motor Y through the limit switch 854 and the transistor 881, and the lifter motor M1853 rotates in the upward direction. The rotational force of the lifter motor M1853 raises the middle plate 1 according to the above-mentioned process, and when the paper on the middle plate 1 pushes up the sensor lever 14, the UP level sensor 809
is activated. When the UP level sensor 809 is activated, the output signal of the UP level sensor 809 is input to the CPU 802 via the receiver 817. CPU
In step 802, when the UP level sensor 809 is activated (step 1092-Y), the
s) After (step 1104) Lifter motor M1
853 is stopped (step 1105). The time after which the motor stops rotating (150ms in the example)
After the elapsed time (step 1109), the holding solenoid 813
Turn OFF (step 1110) and lock the lifter. Also, when the paperless switch is activated, the lifting of the middle plate 1 is similarly stopped.

Here, the operation of the lifter motor M1 control circuit 851 when the lifter motor M1853 stop signal, that is, the M1BK signal is output, will be explained. M1BK/ from the main control circuit 801 of the circuit 851
The ON signal becomes a motor brake level (HIGH level), and the inputs of the motor drive ICs 855b and 855e on the output side of the receiver 855G discharge capacitors 859 and 883 of the time constant circuit via diodes 884 and 885, and become LOW level. Therefore, transistors 863, 864, 8
72 and 874 are in the OFF state and the lifter motor
+24V power will no longer be supplied to M1853.
In addition, the outputs of the brake drive ICs 855c and 855f become HIGH level, and the lifter motor is driven by driving the transistors 868 and 865 and 879 and 881 with a delay set by the time constant of the resistor 870 and capacitor 869 and the resistor 877 and capacitor 878. Short-circuit both poles X and Y of M1853. For this reason, lifter motor M185
3 consumes the electromotive force generated during rotation, so powerful control can be applied.

The lifter has now stopped at a position where paper can be fed and transported. In this state, if there is no paper at the paper sensor 1806 position of the transport section and the paper out switch 805 is not operating, the CPU 802 executes the paper feed control flow KYUSI (step 1030) to feed paper.

First, the transport motor M2815 is driven via the driver 826, and the paper feed solenoid SL1811
is driven via the driver 822 (step
1031). When the paper feed solenoid SL1811 is activated, the one-turn clutch 20 is activated, causing the paper feed drive shaft 21 to rotate. At this time, the transport solenoid
SL2812 is activated. (The reason is shown in FIG. 9.) Here, the paper feed solenoid SL1811 is activated after a sufficient time (100ms in the embodiment) for the stopper of the one-turn clutch 20 to disengage (step 1032).
It is turned off (step 1033). Therefore, the paper feed drive shaft rotates only one rotation, and one sheet of paper is set on the conveyance roller 27 via the paper feed roller. When the paper is set on the transport roller 27 (step
1011-Y) If there is no paper in the paper sensor 2807 (step 1016-N), the conveyance control flow HANSO (from step 1120) is executed. Transport control flow
In HANSO, paper sensor 1806 and paper sensor 28
If there is no paper in 07, first set the jam timer of the conveyance system (300ms in the example) (step
1123). Next, SW1819 or
The CPU 802 reads the stop pulse calculation data (I8 to I11) set by SW2832 and calculates the stop clock (step 1124). Next, the transport motor M2815 is driven and the transport solenoid is
Set SL2812 to non-suction state and transfer motor M28
15 is transmitted to the conveyance rollers 27 and 42a via the one-way clutch 31a, and conveyance of the paper is started (step 1125). Paper sensor 18
When the paper is conveyed at 06, the jam timer is reset and at the same time a new paper sensor 180 is activated.
A jam timer (300 ms in the example) is set from 6 to paper sensor 2807 (step 1137). When the paper is conveyed from the paper sensor 1806 to the paper sensor 2807, the jam timer is canceled, the next jam timer (370 ms in the example) is set (step 1135), and the slit of the clock disk 18a attached to the pulley 18 is opened. The clock sensor 808 detects it, converts it to a clock pulse, and starts pulse counting (step 1136b), and the lamp 81
4 is turned off (step 1136a). When the pulse reaches the stop clock number (step 1130), the transfer solenoid SL2812 is turned on (step 1131),
The conveyance of the paper is stopped and the paper is stopped at a specified position (the position indicated by the dashed line A in FIG. 2).

If the predetermined number of stop pulses do not arrive even after the time set in the stop pulse abnormality timer has elapsed, or if the paper does not reach the paper sensor 1806 and paper sensor 8072 within the specified time from the start of transport, the transport drive system Since a malfunction is suspected, the system is set to flicker mode (step 1139), the transport motor is stopped (step 1140), the transport solenoid is sucked (step 1141), and the transport drive system is stopped.

Here, the conveyance motor M2815 waits for the maximum time of the paper feeding interval time during continuous conveyance (in the example, 1
seconds) is stopped (step 1132). After that, the transfer solenoid SL2812 is turned OFF (step 1021).
When the conveyed paper is taken out from the conveyance unit and there is no paper at the paper sensor 1806 position, the paper feed control flow is executed.Subsequently, when there is no paper at the paper sensor 2807 position, the same conveyance control flow ( HANSO).

After feeding and transporting several sheets of paper, when the level sensor level 14 falls and the UP level sensor 809 stops operating (step 1007), the above-mentioned raising control (from step 1090) is performed and the paper can be fed again. Let the position be PH.

In order to prevent the equipment from being destroyed in the event that the middle plate 1 rises beyond the allowable range due to malfunction of the main control circuit or motor control circuit, etc., the sensor lever protrusion is installed when paper is loaded on the middle plate 1. 14c, if not present, abnormal rise is detected at 14b, the upward protrusion 14a at the base of the arm of the sensor lever 14 operates the limit switch 854, and the lifter motor M185
3. Cut off the power supply for lifting. Also, while the lifter motor M1853 is rising, the limit switch 85
When the switch 854 is activated, the switch 854 is opened, and a potential difference of +24V is generated between the switch poles. This potential difference is reported to the CPU 802 via the diode bridge 887 as a rising abnormality signal via the photocoupler 829 of the main control circuit. CPU
802 detects an abnormal rise (step 1052)
M1DWN/UP signal via driver 828
DWN (step 1053). Then, after a certain period of time (100 ms in the example) has elapsed (step 1054), if an overrun occurs more than a certain number of times (eight times in the example) within a certain period of time (10 seconds in the example), the paper feeding device is stopped (step 1057, 1058). Next, when the intermediate plate 1 is lowered and the abnormal rise is canceled, if it is at the UP level sensor position, the rise control is ended (steps 1060-1063). When middle plate 1 is lowered below the UP level sensor position, lifter motor M185
3 is driven upward (step 1061), and at the same time the control returns to upward control and the number of times the abnormal state is counted is reduced, the abnormal state that has occurred spontaneously is canceled. As a result, even if the limiter switch 854 malfunctions due to paper flapping or the like, normal paper feeding and conveyance can be maintained.

A diode 886 is connected in parallel to the limit switch 854, and when the lifter motor M1853 is rotating upward, +24V is applied to the cathode side of the diode and GND is applied to the anode side of the diode, so the limit switch is opened. When this occurs, a potential difference of 24V is generated between the two poles of this diode, and this potential difference is detected by the diode bridge 887 to detect an excessive rise in the lifter. But lifter motor M18
When the diode 886 is rotating downward, GND is applied to the cathode side of the diode 886, and +24V is applied to the anode side of the diode 886, so that only a small potential difference occurs between the two poles of this diode. For this reason, diode bridge 887
The output remains OFF, so even if the limit switch 854 malfunctions and the contact opens, no malfunction will occur. Also lifter motor
When the brake signal is output to M1853, both the anode side and the cathode side are at GND potential, and even if the limit switch 854 malfunctions, the output signal of the diode bridge 887 remains OFF as in the case of the above-mentioned lowering. Abnormal rise of the plate 1 will not be detected and malfunction will not occur.

When all the sheets on the middle plate 1 are fed, the sensor lever 14c falls into the detection hole 1a on the middle plate 1, and at the same time, the output of the paperless switch 805, which is installed at the above position and has already been detected, is sent to the CPU 802 and sent to the receiver 817. Input via . The CPU 802 is a paper sensor 1806 and a paper sensor 28 in the conveyance section.
When the paper runs out at 07, the lamp 814 is turned on to notify that the paper is out.

When the paper cover is opened or the paper feed device is separated from the recording device etc., the door switch 852 or joint switch 803 is activated (the step
1006), and the descending control flow DCTL (from step 1070) is executed. When the CPU 802 enters the descending control flow, it first enters the flicker mode (step
1071) Turn on the lamp 814, drive the shipping solenoid SL2812 (step 1073), and stop the transport motor M2815 (step 1074).
Next, if the lifter is in the process of rising, the lifter stops rising (from step 1075-Y to step 1105), and the lifter switches to the lowest position, LOW level switch 8.
04 Lifter motor M18 when in operating position
53 (step 1083), and then the holding solenoid SL3813 and the conveying solenoid SL281
2 and locks the lifter motor M1 (step 1086). If the lifter has not descended to the LOW level switch 804 operating position (step 1076-N), first set the holding solenoid SL3813.
(step 1079), lifter motor M18
53 is unlocked, and then CPU802 becomes M1.
to the control circuit via drivers 827 and 828
The M1OF signal and the M1DWN signal are output (step 1081). Thereafter, a timer is set for 10 seconds or more (step 1082), and if the lifter does not finish descending even after 10 seconds, a buzzer is sounded via the driver 830, the LED 810 is lit, and the operation is stopped (step 1057).

Here, when the M1ON signal (LOW level) is input to the M1 control circuit 851, the receiver 855
The output of G becomes OFF (HIGH level), and the brake drive transistors 868 and 879 are turned OFF via the brake drive ICs 855c and 855f.
The brake will be released. At this time, the up/down signal M1DWN/UP signal is M1DWN (HIGH level)
At this time, the output of the receiver 855a becomes LOW level, and the charge of the capacitor 859 is transferred to the diode 85.
Discharge through 7, and after discharging, rise drive IC85
The output of 5b becomes HIGH, which turns off the lifting transistor 863 and turns off the lifter motor.
No rising voltage is applied to M1853. Also
When the output of IC855a becomes LOW level, the output of IC855d becomes HIGH level and resistor 8
The capacitor 883 is charged via the capacitor 882, and the output of the IC 855e becomes LOW level with a time delay during the charging time. As a result, the base current of the lowering transistor 874 flows, and the lowering driving transistor 872 becomes conductive (ON), supplying +24V power to the Y of the lifter motor M1853 via the limiter switch 854 or the diode 886. In addition, the collector current due to transistor 874 turning on turns on transistor 865 through resistor 867, and lifter motor M185
Let X in 3 be the GND level. As a result, the lifter motor M1853 has GND level on X and + on Y.
24V is applied and lifter motor M1 rotates in the downward direction, lowering the lifter.

When the lifter descends and the cam 100 attached to the middle plate 1 activates the LOW level detection switch 804 (step 1076-Y), the M1ON signal is output.
The signal is changed to M1BK and the lifter motor M1853 is stopped (step 1083). Thereafter, after a period of time (350 ms in the example) when the motor stops rotating (step 1084), the holding solenoid SL3813 is turned off to fix the middle plate 1. LOW level switch 804
If the lifter descends too much due to an abnormality, etc., the middle plate 1
hits the bottom plate, but the one-way clutch 6a attached to the drive transmission sprocket 6 causes the drive rotation to idle, protecting the equipment from damage, and a 10-second timer detects an abnormality and stops the motor drive.

Further, as shown in FIG. 12, the middle plate sensor lever 1001 and the level sensor 1001 are rotatably joined on the same shaft, and the sensor positions are detected by the detection unit 80.
5', 809' is detected by the detection section, and the sensor 80
When 5' is in the light shielding state and the sensor 809' is in the transmitting state, there is no paper, which has the effect of eliminating the need to adjust the positions of the paperless switch 805 and the UP level sensor.

Further, in this embodiment, a paper feeding device to a paper processing apparatus has been described, but even if the material of the paper is not paper, it is possible to feed one sheet at a time in exactly the same way as long as it has a paper-like shape. It goes without saying that it can also be used as a feeding device for devices other than paper processing devices that need to use one sheet at a time.

A similar effect can be obtained by detecting the paper size by installing a microswitch in the support box 1501 shown in FIG. 13 attached to the bottom of the chassis or the side plate of the chassis.

Further, as shown in FIG. 14A, the same effect can be obtained by inputting paper size information once to the CPU 802 and selecting paper conveyance stop timing data based on that information.

Further, FIG. 14B shows an example of a configuration when more than two types of paper size data are required.

FIG. 14C shows a configuration in which paper size switching is performed using an ON-OFF switch and an inverter IC.

FIGS. 14D and 14E show a modification example in which a transfer contact is provided.

Effects As explained above, by determining the paper conveyance stop position according to the size of paper stored in the paper storage unit, one paper edge detection unit can accurately stop paper of any size. Since it can be stopped at any position and the paper detection unit can be installed at any position, there are fewer structural restrictions and the end of paper can be easily detected, making it extremely useful when continuously feeding paper, etc. High-speed paper feeding control has also become possible.

In addition, since the stop position is determined according to the paper size rather than the distance from the leading or trailing edge of the paper, it can be used for all paper feeding applications, such as when the operating point of the paper ejecting means is at the center of the paper. For example, a paper feeding device that can be used to take out paper using a robot arm or the like has been realized.

[Effects] As explained above, according to the present invention, the number of pulses counted by the counting means is varied depending on the paper size, and the operation of the conveying means is stopped, thereby achieving a common pulse count regardless of the paper size. It is possible to accurately stop the paper at a predetermined position.

[Brief explanation of drawings]

Fig. 1 is an external view of an embodiment of the present invention, Fig. 2 is a sectional view showing an overview of the mechanism, Fig. 3 is a view showing the lifter mechanism, Fig. 4 is a view showing the conveyance mechanism, and Fig. 5 is a sensor Lever structure diagram Figure 6 is the main control circuit diagram, Figure 7
The figure is a lifter motor control circuit diagram, Figure 8 is a lifter motor control timing chart, and Figures 9 to 1.
Figure 1 is a control flowchart of the control unit, Figure 12 is another configuration diagram of the sensor lever and paperless switch, Figure 13 is another embodiment of the paper size detection unit, and Figure 14 is a diagram of another embodiment of the paper size detection unit.
The figure is a diagram showing another example of the configuration of the paper size information input means. In the drawings, 1...middle plate, 6a, 31a...
One-way clutch, 14...sensor lever, 1
8a...Clock disc, 20...1 rotation clutch, 46...Paper size support cam, 46a...Paper size support knob, 801...Main control circuit, 802
...CPU, 803 ...Joint switch, 8
09...UP level sensor, 811...Paper feed solenoid, 812...Transportation solenoid, 813...
Holding solenoid, 815... Conveyance motor, 851
... Lifter motor control circuit, 852 ... Door switch, 853 ... Lifter motor, 1501 ...
…It is a support box.

Claims (1)

[Claims] 1. A storage section 1 that stores a plurality of sheets of paper, a size detection means 831 that detects the size of the sheets stored in the storage section, and a paper feeder that feeds the sheets of paper stored in the storage section. Paper means 21; Conveyance means 27 and 42 for conveying the paper fed by the paper feed means along the conveyance path; A detection means 807 provided on the conveyance path for detecting the paper; and Counting pulses. a counting means 802, in order to temporarily stop the paper at a common predetermined position A regardless of the paper size on the conveyance path, when the detection means detects the paper and the counting means counts a predetermined number of pulses, the conveyance is stopped; and a control means 801 for stopping the operation of the means, the control means varying the predetermined number of pulses to be counted depending on the paper size detected by the size detection means. Device.