JPS6132218B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides feeding control in a sheet feeding device equipped with a plurality of sheet loading tables, for example, paper feeding tables, on which sheets of a predetermined size, such as paper, are stacked and selectively used. Regarding equipment.

As described above, there is a paper feeder equipped with a plurality of paper feed trays as described in Japanese Patent Application Laid-Open No. 52-113808 = Japanese Patent Publication No. 61-3731. In this paper feeder, multiple paper feed trays (that is, paper feed systems) are weighted, and when selecting one of the paper feed trays when feeding paper, the paper feed trays are selected in order of weight. is being carried out.

However, in this device, paper feed trays are simply selected in accordance with the weighted order, and the state of the paper stacked on those paper feed trays is not taken into account at all. Therefore, when attempting to copy a relatively large number of sheets, if only a few sheets of paper are loaded on the initially selected paper feed tray, it will take a short time to complete the copying work for that number of sheets. Copying operations may have to be interrupted after a certain amount of time has elapsed.

In this case, even if the paper of the same size is loaded on the next paper feed tray and the paper on one paper feed tray runs out after a short period of time as described above, the next paper feed tray will be loaded with paper of the same size. It is also possible to feed sheets of the same size one after another. However, in general, when there are only a few sheets of paper on the paper feed table, double feeding of paper, jams, etc. are likely to occur in the paper feed device, and paper feeding is likely to become unstable. Therefore, even if an attempt is made to continuously feed a large number of sheets by switching the sheet feed table, the copying operation is often forced to be interrupted due to the unstable sheet feeding.

In view of the above points, it is an object of the present invention to provide a sheet feeding control device that enables continuous feeding of as many sheets as possible always reliably and smoothly.

The purpose of this is to provide a first detection means for detecting the stacking height of the sheets stacked on each sheet mounting table, a storage means for storing the output of the first detection means, and a stacking height of the sheets stored in the storage means. This is achieved by providing a control means for selecting a sheet mounting table on which a large number of sheets are stacked from among a plurality of sheet mounting tables based on the height information.

Hereinafter, the present invention will be explained by examples.

FIG. 1 is a schematic configuration diagram of a plurality of sheet loading tables, such as a paper feed stand, in a copying machine to which the present invention is applied, and this figure shows a copying machine with three paper feed stands. It is something.

In FIG. 1, 1, 2, and 3 indicate first, second, and third paper feed trays, and 4 indicates a double-sided tray, respectively. The duplex tray 4 is a paper feeding/discharging tray for copying both the front and back sides.

The first, second and third paper feed trays contain sheets of the same or different sizes, e.g.
6 are stacked.

On the other hand, 5 is a photoreceptor drum, and the photoreceptor drum 5
In order to convey the transfer paper 16 on the paper feed table between the transfer charger unit that transfers the electrostatic image on the top and the photosensitive drum 5, the calling rollers 6-1, 6-2 and 6-3 are separated. Roller pairs 7-1 and 7-2, 7
-3 and 7-4, 7-5 and 7-6, 7-7
and 7-8, feed roller pair 8-1, 8-
2, 8-3 and 8-4, diagonal rollers 9 and 1
0, the registration rollers 11 are arranged in this order, and if the selected paper feed tray is the second paper feed tray 2, the calling roller 6-2 rotates and moves to the second paper feed tray. The transfer paper is called out one by one by the roller 6.
-2, passes between the pair of separation rollers 7-3 and 7-4, and is then pulled out by the feed rollers 8-2, 8.
-1, diagonal rollers 9 and 10, and registration rollers 11, and are transported to the transfer charger section.

Further, the transfer paper onto which the electrostatic image has been transferred in the transfer charger section is conveyed by a conveyor belt 12, further passed through a fixing roller 13, fixed, and discharged to a paper discharge unit 14. In the case of double-sided transfer, the paper is discharged to the double-sided tray 4, transferred and fixed again in the same manner as described above, and then discharged to the paper discharge unit 14. 15 is a paper discharge tray.

On the other hand, to explain the first paper feed tray as an example, as shown in FIG. The paper feed table 1 is configured to be moved up and down by a belt 20. Further, for example, a detection metal fitting 26 is fixed to the other end of the arm 23 which is swingably provided around the feed roller shaft, and one end of the detection metal fitting 26 is brought into contact with the top surface of the transfer paper 16 on the paper feed table 1. , the other end of the detection fitting 26 is opposed to the micro switch 29 for detecting the position of the top of the transfer paper, and when the top surface of the transfer paper 16 comes into pressure contact with the calling roller 6-1, the other end of the detection metal fitting 26 is opposed to the micro switch 29 for detecting the height. switch 29
At this time, the height detection micro switch 29 is turned on. So motor 1
By raising and lowering the paper feed tray 1 by the roller 7, the paper feed tray 1 is maintained such that the top of the transfer paper 16 on the paper feed tray 1 is in pressure contact with the calling roller 6-1.

Further, an actuator 32 is fixed to the paper feed tray 1, and when the paper feed tray 1 rises due to a decrease in the amount of transfer paper on the paper feed tray 1, the paper comes into contact with the actuator 32 and is turned on. Micro-switches 35, 38 and 41 are provided for detecting the amount of lamination. In the case of FIG. 2, in which the maximum specified amount of transfer paper is stacked on the paper feed tray 1, the detection micro switch 35 is turned on, copying progresses, and the paper feed tray 1 is stacked.
The detection micro switch 38 is turned on at the position of the paper feed tray 1 when the amount of transfer paper 16 on the paper feed tray 1 reaches approximately 1/2 of the maximum prescribed amount.

Further, the detection micro switch 41 is turned on at the position of the paper feed tray 1 when the copying progresses and the paper feed tray 1 rises and the number of remaining transfer sheets 16 on the paper feed tray 1 reaches a predetermined number. Become. In this way, the microswitch 41 functions as a first detection means for detecting the amount of paper stacked, and also functions as a third detection means for detecting that the number of remaining papers has decreased to a predetermined number.

Further, a transfer paper detection sensor 44 as a second detection means for detecting the presence or absence of the transfer paper 16 is fixed to the detection metal fitting 26.

The transfer paper detection sensor 44 is composed of a pair of light emitting diodes and a phototransistor, and the light from the light emitting diode is reflected by the transfer paper 16, and this reflected light is received by the phototransistor, so that the transfer paper 16 is placed on the paper feed table 1. Detect existence. The surface of the paper feed tray 1 is coated with paint that absorbs light from the light emitting diodes, and when the transfer paper 16 runs out, the light from the light emitting diodes is absorbed by the surface of the paper feed tray 1 and enters the phototransistor. The light emitted decreases, and the phototransistor is no longer sensitive to it, and the absence of the transfer paper 16 is detected.

The above description has been made using the first paper feed tray 1 as an example, but the same applies to the second and third paper feed trays 2 and 3, and the respective motors and sensors shown in parentheses in FIG. , a micro switch is provided.

Next, a case will be described in which paper feeding is controlled by a microcomputer system using each of the above detection signals. This microcomputer system functions as a control means for controlling the feeding of the transfer paper.

FIG. 3 is a block diagram of the microcomputer system. This system includes a central process unit (hereinafter referred to as CPU) 47, a read-only storage device (hereinafter referred to as ROM) 48, and a readable/writable storage device (hereinafter referred to as RAM).
49, and input/output interface adapters (hereinafter referred to as IOAs) 50, 51, and 52. 53 is a system bus line.

The CPU 47 successively reads and executes programs written in the ROM 48 in synchronization with clock pulses. Signals input through the IOAs 50, 51, and 52 are input to the RAM 49 or the register of the CPU 47, and are operated and processed as one operand.

As an example of using a device in which the RAM 49 and the IOA 50 are integrated as the IOA 50, FIG. 4 shows input signals to the IOA 50 when an Intel 8155 is used. The 8155 device can control ports A, B, and C by inputting the necessary data to the command status register.

In FIG. 3, the signals input to the IOA 50 are the signals a of the height detection microswitches 29, 30, and 31 of the transfer paper 16 on the first, second, and third paper feed trays 1, 2, and 3. ₁₀ , a ₁₅ and b ₁₂ ,
Signals a ₁₁ , a ₁₆ and a ₁₃ of transfer paper detection sensors 44, 45 and 46 which also detect the presence or absence of transfer paper,
Micro switch 3 that also detects the amount of stacked transfer paper
Signals 5 to 43 a ₁₄ , b ₁₁ , b ₁₆ , a ₁₃ , b ₁₀ , b ₁₅ ,
a ₁₂ , a ₁₇ , and b ₁₄ , and in addition to that, an output signal from a key switch for setting the number of copies is input to port C.

Next, FIGS. 5a and 5b are diagrams showing the output signals of the IOAs 51 and 52, and the IOAs 51 and 52 are used as output ports, for example, in a device in which the ROM 48 and the IOA are integrated, such as Intel's
8755 is used. FIG. Said
The 8755 device can be used as a ROM and to control ports A and B through the system bus line.

The IOA 51 shown in Fig. 5a has a 7-segment numeric display tube LED ₁ to display the set number of copies.
LED ₃ is connected to 7-segment numeric display tubes LED ₄ to _{LED 6} for displaying the number of copies to be printed, respectively.

The IOA 52 shown in FIG. 5b includes a lamp 53 indicating the size of the transfer paper selected from its port A, a lamp 54 indicating the absence of transfer paper by the transfer paper detection sensors 44, 45 and 46, and a detection micro switch 41. , 42, 43 to output to the display lamp 55 which indicates that the remaining number of transfer sheets has reached a predetermined value. Note that the size of the transfer paper stacked on each paper feed table 1, 2, and 3 is determined by the slider that comes into contact with the side of the transfer paper when stacked on the paper feed table is fixed, and the signal of the position of this slider is The size of the transfer paper stacked on the paper feed tray is stored in the storage device in correspondence with the paper feed tray.

The signal is output from the B port of the IOA 52 to the display lamp 56 which displays the selected paper feed tray. The selected paper feed tray is displayed by this output.

Next, FIG. 6 shows a flowchart of paper feeding control performed by this computer system.

First, the operator sets the number of copies _n1 in step 1 before starting copying. The set number is displayed by LED ₁ to _{LED 3} . Next, in step 2, the transfer paper size is specified, and this size is displayed by the display lamp 53. In step 3, specify the paper feed tray if necessary. A case will now be described in which a specific paper feed tray is designated and there are too many transfer sheets on the paper feed tray.

According to the specification of the paper feed tray, the designated paper feed tray is selected in step 5, and copying is started by operating the copy start push button in step 6. Then, in step 7, a clutch is activated to rotate the calling roller of the copy table selected in step 5 in step 6, and the calling roller starts rotating to feed paper. Since the transfer papers are now sufficiently stacked on the selected paper feed table, there is no signal (near-end signal) indicating that the number of remaining copies has reached the predetermined value in step 8, and the number of copies to be processed and the set number of copies are compared in step 26. , when the number of copies to be processed n ₀ =n ₁ , the copying ends at step 28.

Note that the number of copies to be processed n ₀ is, for example, the number of copies processed by the fixing roller 1.
A microswitch or a photocoupler is provided on the paper ejection side of No. 3, which turns on and off as the transfer paper passes, and the number of pulses caused by the passage of the transfer paper is obtained by subtracting the number of copies set by the key switch.

Next, if the paper feed tray is not specified in step 3, the paper feed tray is accessed in step 15, and if there are two or more paper feed trays stacked with transfer paper of the size specified in step 2. It is determined in step 17 whether the If there are only 1 and not 2 or more, a paper feed tray on which transfer papers of the specified size are stacked is selected in step 22, and copying is started in step 6. If there are two or more paper feed trays in step 17, the amounts of transfer paper on the paper feed trays are compared in steps 19 to 25, and the paper feed tray with the most transfer paper is selected. In this case, the comparison is made based on the on/off states of the microswitches 35 to 43 for detecting the amount of lamination. By pressing the copy start button in step 6, paper is fed from the paper feed table selected in steps 19-25.

Next, while the copying operation is in progress, micro switches 41, 42, 4 are activated to indicate that the remaining number of sheets of transfer paper on the paper feed table has decreased to a predetermined value.
If step 3 is detected, another paper feed table is accessed in step 9, and if there is a paper feed table on which transfer paper of the same size is stacked in step 29, paper is fed in step 10 in the same flow as steps 15 to 25. The amounts of transfer paper on the trays are compared, and in step 11, the paper feed tray with the largest amount is selected. Then step 12
In step 13, paper feeding is continued until there is no more transfer paper on the paper feed tray, that is, the remaining number of transfer paper sheets has decreased to a predetermined value. When there is no transfer paper, the copying is continued by switching to the selected paper feed tray in step 10. Then, in step 14, the paper feed tray before switching is displayed as being out of paper.

Next, in step 29, if there is no paper feed tray stacked with transfer paper of the same size, steps 31 and 32 continue feeding paper from the paper feed tray that is currently feeding, and when there is no more transfer paper, step 32 is performed. Displays the paper out status, stops the copying machine, and waits for it to be replenished.

Next, in the above explanation, the stacking height of the transfer paper stacked on each paper feed table was detected by the micro switches 35 to 43. In the above example, three points were detected per paper feed tray. Therefore, as shown in FIG. 7, a variable resistor 57 is provided and its sliding piece is connected to
The actuator 32 may be moved in conjunction with an actuator 32 fixed to the actuator 32, and the position of the actuator 32 may be detected using a potentiometer. In this case, variable resistor 57
The output of is input to an analog-to-digital converter 58,
All you have to do is input it into IOA50 after digital conversion.

When using this detection method, the amount of stacked transfer paper on the paper feed table can be outputted with high precision, and the comparison of the stacked amount of transfer paper on each paper feed table can also be made with high precision.

In addition, when detecting the amount of stacked paper on the paper feed tray using this method, a micro switch operated by an actuator fixed to the paper feed tray must be separately installed or other device to detect when the stack amount has decreased to a predetermined value. It is necessary to set it using this method.

As is clear from the above description, according to the present invention, when selecting a plurality of sheet mounting tables, the sheet mounting table on which a larger number of sheets are loaded is selected. Therefore, as many sheets as possible can always be fed from one sheet mounting table, and as a result, a large number of sheets can be fed reliably and stably continuously.

Further, when the remaining number of sheets decreases to a predetermined number, another sheet mounting table is selected in advance, and when there are no more sheets left, the system switches to the other sheet mounting table and continues feeding. Therefore, more time can be obtained than in the case where another sheet loading table is selected and preparations for feeding are made only when the sheet runs out.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a plurality of paper feed trays of a copying machine or the like to which the present invention is applied. FIG. 2 is a schematic diagram showing the mechanism of the paper feed tray and the relationship between each switch and sensor. FIG. 3 is a block diagram of an embodiment of a microcomputer system used for sheet feeding control of the present invention. 4, 5a and 5b are diagrams showing input and output signals of the IOA of the system of FIG. 3; FIG. FIG. 6 is a flowchart of paper feeding control performed by the microcomputer system of FIG. 3. FIG. 7 is a diagram for explaining the detection of the stacked thickness of paper on the stacked paper feed tray. 1, 2, 3... Sheet mounting table (paper feeding table), 16...
Sheet (transfer paper), 17, 18, 19...motor,
20, 21, 22... Belt for lifting and lowering the paper feed tray, 29,
30, 31... Micro switch for detecting the top position of transfer paper, 32... Actuator, 35-43,
57...First detection means (micro switch for detecting height of laminated transfer paper), 44, 45, 46...Second detection means (transfer paper presence/absence detection sensor), 41, 42, 4
3...Third detection means (micro switch for detecting a predetermined number of remaining sheets of paper), 47...CPU, 48...ROM, 49...
RAM, 50, 51, 52...IOA, 53...System bus line.

Claims (1)

[Scope of Claims] 1. In a feeding control device for a sheet feeding device equipped with a plurality of sheet stacking tables, each of which has sheets of a predetermined size stacked thereon and selectively used, the sheets stacked on each sheet stacking table. a first detecting means 35 to 43, 57 for detecting the stacking height of the sheets; a memory means (RAM) for storing the sheet stacking height information from the first detecting means; A sheet feeding control device comprising: control means for selecting a sheet mounting table on which a large number of sheets are stacked from among the plurality of sheet mounting tables, based on stacking height information. 2 second detection means 44, 45, 46 for detecting the presence or absence of sheets on each sheet mounting table; The sheet feeding control device according to claim 1, further comprising a control means for selecting a sheet loading table on which a large number of sheets are loaded from among the plurality of sheet loading tables. 3. A memory means (RAM) for storing the size of the sheets stacked on each sheet mounting table; and a memory means (RAM) for storing sheets of the same size among the plurality of sheet placing tables, based on the size of the sheets stored in this storage means. Claim 1, characterized in that it has a control means for selecting a stacked sheet mounting table and further selecting a sheet mounting table on which a larger number of sheets are loaded from among the sheet placing tables.
The sheet feeding control device according to item 1 or 2. 4. In a feed control device of a sheet feeding device equipped with a plurality of sheet stacking tables each having a predetermined size of sheets stacked thereon and selectively used, the stacking height of the sheets stacked on each sheet stacking table is detected. first detection means 35 to 43, 57; second detection means 44, 45, 46 for detecting the presence or absence of sheets on each sheet placement table; and the number of sheets on each sheet placement table reduced to a predetermined remaining number due to use. third detecting means 41, 42, 43 for detecting that the sheet has been stacked; and a memory means (RAM) for storing sheet stacking height information from the first detecting means and the size of the sheets stacked on each sheet mounting table. , When the third detection means detects that the number of sheets on the selected sheet mounting table has decreased to a predetermined remaining number, the number of sheets on the selected sheet mounting table is reduced to a predetermined remaining number based on the size of the sheets stored in the storage means. If another sheet mounting table stacking sheets of the same size as the sheets on the sheet mounting table is selected, and there are two or more of the selected sheet placing tables, the sheets stored in the storage means mentioned above are stored. The sheet loading table on which a larger number of sheets are loaded is selected based on the stacking height information of the sheet loading table, and the third detecting means detects that the number of sheets has decreased to a predetermined remaining number. When the second detection means detects that there are no more sheets, control continues to feed the sheets by switching to the other sheet loading table selected as having more sheets loaded thereon. A sheet feeding control device comprising: means.