JPS60236952A - Sheet feeder - Google Patents

Abstract

PURPOSE:To detect the residual quantity of sheets easily and correctly by calculating the travel of a support for sheets according to the number of pulses supplied to a stepping motor to detect the residual quantity of sheets in a sheet feeder using a stepping motor. CONSTITUTION:A feeder body 1 which can be installed on a copying apparatus body 2 has a support 5 for supporting stacked sheets 4, and the support 5 is moved up and down by a driver 6 operated by a stepping motor 7. The stepping motor 7 is controlled with a display unit 12 for displaying the residual quantity of the sheets 4 by a control circuit 13 through a driving circuit 14. In this arrangement, the control circuit 13 is adapted to calculate the travel of the support 5 according to the number of pulses supplied to the stepping motor 7, and detect the residual quantity of the sheets 4 according to the travel to be displayed on the display unit 12.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a paper sheet feeding device suitable for application to, for example, a copying machine.

[Prior Art] Conventionally, in a large-capacity sheet feeding device used in a copying machine, etc., a long variable resistor whose resistance value changes in conjunction with the movement of a support supporting the sheet is used. The remaining amount of paper can be detected by installing a sensor and detecting changes in its resistance value, or by installing detectors at multiple detection points in the device to detect the presence or absence of paper. was.

However, these conventional devices require a special detector only for the purpose of detecting the remaining amount of paper, in addition to a detector for controlling the movement of the support that supports the paper. However, there was a drawback that it was difficult to accurately detect the remaining amount.

[Objective] In view of the above-mentioned points, an object of the present invention is to detect the remaining amount of paper sheets using a stepping motor controller, thereby making it possible to accurately measure the amount of paper sheets with a simple configuration. It is an object of the present invention to provide a paper sheet feeding device configured to detect the remaining amount.

In order to achieve such an object, in the present invention, in a paper sheet feeding device using a stepping motor, the amount of movement of the paper sheet support is calculated based on the number of pulses supplied to the stepping motor. Configure it to detect the remaining amount. In other words, in the present invention, the moving distance of the support that supports the paper sheet is proportional to the rotation angle of the stepping motor that moves this support, and this rotation angle is output from the controller that controls the stepping motor. This was done based on the knowledge that it is proportional to the number of control pulses.

[Example] Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 shows the configuration of an embodiment of the present invention, in which 1 is a paper sheet feeding device main body, 2 is a copying device main body, and 3 is a paper sheet feeding device main body 1 attached to the copying device main body 2. This is a micro switch that turns on. 4 is paper, 5 is a support that supports the paper, 6 is a driver that moves the support 5 both up and down, 7 is a stepping motor that operates the driver, and 8 is turned on when the support 5 moves to the lower limit. 9 is a microswitch that turns on when the top surface of the paper 4 supported by the supporter 5 moves to the upper limit; 10 is the lid of the feeding device body 1; 11 is OFF when the lid 10 is opened. microswitch, 12 is paper 4
13 is a control circuit that controls the stepping motor 7 and the display unit 12; 14 is a drive circuit for the stepping motor 7;

FIG. 2 shows the configuration of the drive circuit 14 for the stepping motor 7. As shown in FIG. In Fig. 2, the same reference numerals as in Fig. 1 indicate the same parts, and T1 to T8
1 is a transistor for controlling the current supplied to the stepping motor 7, R1 to R15 are resistors, 15 to 20 are diodes, 21 and 22 are Zener diodes, and 23 to 30 are inverters.

As shown in FIG. 2, the control circuit 13 receives signals S3 +S8 +S9 from the microswitches 3, 8, 9 and 11.
+SI+ outputs a signal to the display unit 12 and also controls the stepping motor 7. Signals A, B, HO
The LD is output to the driving circuit of the stepping motor 7. When operating the stepping motor 7, the signal) 1
0LD is set to the "H" level, transistor T6 is turned on, and power is supplied to the stepping motor 7 from the +24V power supply. In this state, the stepping motor 7 is rotated forward or reverse by sequentially changing the values of the signals A and H. For example, in the case of forward rotation, from the state where the signal A is II HIl and the signal B is °°H', the signal A is II L 11 and the signal B is °°H'
”, and then set the signal A to “L”’ and the signal B to “
'L°' state. Then, the stepping motor 7
When the rotation angle reaches the desired rotation angle, the signal HOLI) is changed to °゛L'' and the +5V power is applied to the stepping motor 7.
and hold the position.

Diodes 15-18 and Zener diodes 21.2
Reference numeral 2 is for quickly removing the current due to the back electromotive force generated in the coil in the stepping motor 7 when the values of the signals A and B change.

FIG. 3 is a block diagram of a one-chip microcomputer that constitutes the control circuit 13, and 31 is an RO that stores a program.
M, 32 is RAM used for storing numerical values, etc.
3 is a calculation circuit, 34 is a micro switch 3,8゜9.1
An input port 35 inputs the signals s3+S8+S9+SI+ from 1, and 35 is a drive circuit 14 shown in FIG. This is an output port for outputting to.

Next, the control procedure of this embodiment will be explained using FIG. 1, FIG. 4, FIG. 5, and FIG. 6.

FIG. 4 is a flowchart showing the main routine of this embodiment.

First, as shown in FIG. 4, this embodiment starts operating when the power is turned on. In step S1, a counter storing the remaining amount of paper is cleared.

In step S2, it is determined whether the microswitch 8 shown in the first diagram is on or off (whether the support 5 is located at the lower limit or not), and if it is determined to be off (if the support 5 is not located at the lower limit) ), proceed to step S3.

In step S3, one pulse is output to reversely rotate the stepping motor 7, and the support 5 is moved downward.

In this way, in steps S2 and S3, the support 5 is moved downward until the support 5 shown in the first diagram moves to the lower limit. When the support body 5 reaches the lower limit, the micro switch 8
is turned on, and the process advances from step S2 to step S4.

In step S4 and step S5, interrupt processing, which will be described later, is performed.

In step S8, it is determined whether the microswitch 9 shown in the first diagram is on or off (whether the top surface of the paper 4 is located at the upper limit or not), and if it is determined to be off (the top surface of the paper 4 is located at the upper limit or not). If not, the process advances to step S7.

In step S7, one pulse is output to rotate the stepping motor 7 in the forward direction, and the process returns to step S6 via steps S4 and S5.

Thereafter, in this manner, the support body 5 is moved upward until the upper surface of the paper 4 shown in the first figure reaches the upper limit.

When the upper surface of the paper 4 reaches the upper limit, the microswitch 9 is turned on and the upward movement of the support 5 is stopped.

Then, when the paper 4 is supplied and the microswitch 9 is turned off, the process proceeds from step S6 to step S7 again, and the support body 5 moves upward.

Step S5 is an interrupt process 1 that displays the remaining amount of paper 4 and performs processing when the remaining amount runs out, and the routine thereof is shown in FIG.

In FIG. 5, in step S8, the number of pulses output in step S7 shown in FIG. 4 is counted, and the remaining amount of paper is calculated from that number by a method described later.

In step S9, the result obtained in step S8 is
It is displayed using the illustrated display section 12.

In step S10, the presence or absence of paper is determined based on the result of step S8, and if there is paper, the process returns to the main routine. If it is determined that the paper has run out, the process proceeds to step Sl+ and the operation of the copying machine main body 2 is interrupted until paper is replenished.

In step S12, it is determined whether the microswitch 11 shown in the first diagram is on or off (whether the lid 10 is closed or not),
If it is determined that the lid is off (to replenish paper 4, etc.)
0), the process returns to the main routine.

Next, "interrupt processing 2" in step S4 (see Figure 4)
Explain. This "interrupt process 2J" is performed when the paper sheet feeding device main body l shown in the first figure is not attached to the copying machine main body 2 or when the lid 10 of the paper sheet feeding device main body l is open. The routine is shown in FIG. 6. In step S13, it is determined whether the microswitch 11 shown in FIG. It is determined whether one of the microswitches 3 shown in FIG. The lid 10 is closed, and the paper sheet feeding device main body 1
is attached to the copying apparatus main body 2), the process returns to the main routine, and if either the microswitch 3 or 9 is off, the process proceeds to step S15.

In step S15, the memory of the counter storing the remaining amount of paper is cleared.

In step 91B, it is determined whether the microswitch 8 shown in the first diagram is on or off (whether or not the support 5 is located at the lower limit), and if it is determined to be off (if the support 5 is not located at the lower limit). ), the process advances to step S17.

In step S17, one pulse is output to reversely rotate the stepping motor 7 to move the support 5 downward.

In this way, in steps S18 and S17, the support 5 is moved downward until the support 5 shown in the first diagram is located at the lower limit. When the support body 5 reaches the lower part, the microswitch 8 is turned on, and the process returns from step Sl[i to step SI3.

That is, in "interruption processing 2", when the user opens the lid 10 of the paper sheet feeding device main body 1 to replenish paper 4, the support 5 lowers to the lower limit and the remaining amount of paper is memorized. The memory of the current counter is cleared.

Next, a method of calculating the remaining amount in step S8 shown in FIG. 5 will be explained.

Let L be the distance from the position where the support body 5 shown in the first diagram presses the microswitch 8 to the position where the support body 5 itself presses the microswitch 9. In addition, the support 5
Let N be the number of pulses given to the stepping motor 7 necessary to move the stepping motor 7 by L. Then, if the value obtained by dividing L by N is defined as a sentence, the sentence becomes the moving distance that the support body 5 moves with one pulse.

The number of pulses given to the stepping motor 7 from the state in which the support body 5 presses the microswitch 8 until the support body 5 moves upward and the second side of the paper 4 presses the microswitch 9 is n. This means that the support 5 has moved a distance ′ given by sentence×n. Since the remaining amount of paper is proportional to the distance after subtracting Shirasu', the one-chip microcomputer that makes up the control circuit 13 calculates the amount of paper remaining based on the number of pulses that the one-chip microcomputer itself gives to the stepping motor 7. The amount can be calculated.

The copying machine body 2 consumes paper and the micro switch 9
If the number of pulses required for the support 5 to move upward according to the output signal of the control circuit 13 and for the paper 4 to press the microswitch 9 again from the state in which the paper 4 is turned off is △n1, then the support 5 has further moved from the initial state by a distance given by tachi×Δn1. That is, the remaining amount of paper 4 at this point is proportional to the distance given by L-text X (, n+Δn+).

1. When the paper is consumed one by one, the stepping motor 7 repeats the above operation under the control of the control circuit 13, so the remaining amount of paper can be calculated from the distance given by the following formula.

The remaining amount is displayed by the control circuit 13 controlling the display unit 12, and is shown as a “% display” or a “number of sheets display j.The display unit 12 also includes a meter, LED,
A liquid crystal or any other display means can be used.

Here, a specific example will be given and explained. The stepping motor has a minimum rotation angle of 15°, and L=500 (mm). Now, if 500 pulses are required to move the support 500 (mm), then N = 500, so
L/N = 5001500 = 1 (mm), that is, S2 When one pulse is given to the chipping motor 7, 1 (mm)
The support body 5 moves by that amount. Here, the number n of pulses given to the stepping motor '7 until the supporting member 5 moves upward and the two sides of the paper 4 press the micro switch 9 is n.
is 300, the support body 5 is 1 (mm) x 300
= 300 (mm), so 50
0-300 = 200 (mm) is proportional to the remaining amount of paper. That is, if "% display" is to be performed, it can be calculated that there is a remaining amount of 2001500 x 100 = 40% at the present time.

After that, if paper 4 is supplied and 50 pulses are output from the control circuit 13 to the stepping motor 7, and paper 4 is further supplied and 50 pulses are output, then Δn1=
50. Δn2=50, 500− I
00+50+50)=100100(corresponds to the new remaining amount, and can be calculated as 1001500=20%.

Furthermore, if the paper 4 is consumed and the support 5 has moved 500 mm, the remaining amount of paper will be 0% and the paper 4 will be refilled. Become.

- As explained above, in the wood embodiment, when the paper 4 is consumed, the control circuit 13 controls the stamping motor 7.
The support body 5 moves upward until the upper surface of the paper 4 operates the microswitch 9, and the paper 4 is moved in the control circuit 13 based on the number of pulses output from the control circuit 13. The remaining amount is calculated and the result is displayed on the display section 12. In this manner, in the wooden embodiment, the remaining amount of paper 4 can be accurately detected without providing a special detector for detecting the remaining amount of paper 4.

Below-1- In the embodiment described, the microswitch 9
The detection accuracy can be further improved by using a highly accurate one or by using other equivalent detection means. Furthermore, the detection accuracy can be improved by using a stepping motor 7 with a small minimum rotation angle, or by using a gear or the like to reduce the distance that the support 5 moves with respect to one pulse. If the detection accuracy is based on one sheet, it is also possible to display the remaining amount in units of sheets.

Furthermore, if a means is added for causing the shaft of the stepping motor 7 to maintain its current position when the power is turned off, and a means for storing the remaining amount of paper 4 at that time in a non-volatile memory, Immediately after turning on the switch, the series of steps of moving the support 5 to the lower limit and then moving it upward can be omitted, and the paper feeding operation can be started immediately, and the remaining amount of paper 4 is displayed. I can do it.

[Effects] As described above, according to the present invention, it is possible to obtain an unprecedented effect that the remaining amount of paper sheets can be accurately detected with a simple configuration.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the configuration of an embodiment of the present invention, Fig. 2 is a diagram showing the electric circuit of the embodiment shown in Fig. 1, and Fig. 3 is a diagram showing the one-chip microcomputer that constitutes the control circuit. Block diagram, 5 Figure 4 is a flowchart 1 showing the main routine of the program stored in the ROM in the one-chip microcomputer, and Figure 5 is a flowchart 1 showing the interrupt processing 1 routine.
・, Figure 6 is flowchart 1 showing the routine of interrupt processing 2.
・It is. ■...Paper supply device main body, 2...Copying device main body, 3.8. l], +1...micro switch, 4...
Paper, 5... Support, 6... Drive body, 7... Stepping motor, 10... Lid, 12... Display section, 13... Control circuit, S1-Sl? ...step. 6

Claims (1)

[Claims] ) In a paper sheet feeding device using a stepping motor, the amount of movement of the paper sheet support is calculated based on the number of pulses supplied to the stepping motor. A paper sheet feeding device characterized by detecting the remaining amount. 2. A paper sheet feeding device according to claim 1, characterized in that when the power is cut off, the remaining amount of the paper sheet at that time is stored in a non-volatile memory. Feeding device. 3) The paper sheet feeding device according to claim 1, further characterized in that the remaining amount is displayed. (Hereafter, margin)