JPH0812131A - Residual quantity detecting device for recording paper or the like - Google Patents

Abstract

PURPOSE:To detect also the near end beside the paper end by arranging sensor holes in a detecting arm lowering by following reduction in a residual quantity of recording paper or the like, and arranging the plural sensor holes in the vertical direction when these sensor holes are detected by a sensor. CONSTITUTION:Three holes H1 to H3 are formed in order from below in a detecting arm 16. In this case, the two holes H2 and H3 of the uppermost part are set in an end area A, and the hole H1 of the lowest part is set in a near end area B, and an area below the hole H1 is set in a full area C. A pair of photointerrupters or the like are used in a sensor 18, and this is set on a device frame body 15 above a paper feeding tray. Therefore, recording paper 2 is consumed and reduced, and a recording paper upper surface position is lowered and approaches the paper end, and when the hole H1 reaches a sensor 18 position, and next, when the holes H2 and H3 reach the sensor 18 position, the sensor generates an ON-OFF pulse signal, and this signal is processed, and a residual quantity is judged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic sheet feeder having a mechanism for taking out a sheet of a plurality of sheets of recording paper or originals one by one and feeding the sheet in a printing apparatus, a copying apparatus or an image reading apparatus. The present invention relates to a remaining amount detecting device for recording paper or the like that can accurately detect near-end and paper end of recording paper or the like with a simple configuration.

[0002]

2. Description of the Related Art In a device such as a printing device, a copying device, and an image reading device, which has a mechanism for feeding recording papers or originals, a plurality of recording papers are taken out one by one and printed. The sheet is fed and conveyed to a unit, a reading position, or the like. Displaying the remaining amount of recording paper or the like and the paper end to the operator helps improve various operability. Therefore, most devices have a function of displaying the paper end or near end. FIG. 5 is a perspective view showing the structure of a conventional automatic paper feeder, and FIGS. 6 (a) and 6 (b) are sectional views showing a mechanism for detecting paper end and near end in the paper feeder. The recording papers 2 stacked in the paper feed tray 1 are taken out one by one by the rotation of the meniscus roller 4 fixed to the shaft 3 and fed. The shaft 3 is driven by a motor 7 via gears 5 and 6. Reference numeral 8 is a corner claw for separation.

A recording paper 2 is pivotally supported at one end so as to be movable up and down and a bottom plate 10 biased by a spring 11 and a pedestal 1
It is placed over 2. A detection arm 16 is supported by a frame 15 located above the tray 1 so as to be vertically movable, and a roller 17 is rotatably supported at the lower end of the arm 16. The roller 17 is located above the pedestal 12. Reference numeral 18 is a paper sensor fixed to the frame body 15, and is composed of a photo interrupter or the like. The paper sensor 18 has one sensor hole 19 at the upper end, and the paper sensor 18 detects the presence or absence of this hole. An opening 12a is formed on the upper surface of the pedestal 12 corresponding to the position of the roller 17.
When there is no recording paper on the base 12, the roller 17 is configured to drop downward from the opening 12a by its own weight. In this embodiment, the sensor hole 1
When 9 enters the photo interrupter (a pair of a light emitting element and a light receiving element) that constitutes the paper sensor 18, it shifts from OFF to ON, so that the paper end can be detected. In this device, in order to detect the near end, it is necessary to arrange two pairs of sensors each including a light emitting element and a light receiving element in a vertical positional relationship. That is, in this case, it is necessary to configure so that when the sensor pair located above is turned on (when the sensor hole is detected), the near end is detected, and when the sensor pair located below is turned on, the paper end is detected. . However, since the above-mentioned conventional detection device requires two pairs of sensors, there are problems that the number of parts is increased and the configuration is complicated, and improvement of this point has been desired.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and a detecting arm that descends following a decrease in the remaining amount of recording paper and a sensor for detecting a sensor hole provided in the detecting arm. In the remaining amount detection device equipped with the above, by arranging a plurality of sensor holes in the vertical direction, it is possible to detect not only the paper end but also the near end by a single sensor The purpose is to provide a device.

[0005]

To achieve the above object, the present invention is provided with a detection arm which is placed on the upper surface of stacked sheets and which moves up and down in accordance with the increase and decrease of the position of the upper surface of the sheet, and the detection arm. In a remaining amount detecting device including a sensor for detecting a hole, a plurality of the holes are formed in the detection arm in the vertical direction, and the hole is composed of two sets of holes, and the one set is composed of: The near-end detection hole is arranged to be detected by the sensor when the remaining amount of the paper is near-end, and the other set is detected by the sensor when the paper runs out. And a detection arm that is placed on the upper surface of the stacked sheets and that moves up and down as the position of the upper surface of the sheets increases and decreases, and a hole formed in the detection arm. Sen to detect In the remaining amount detection apparatus provided with the bets,
A plurality of the holes are formed in the detection arm along the vertical direction, and the holes are composed of two or more sets of holes. One set of the sensors is provided when the remaining amount of the sheet is near end. The other set consists of holes for near-end detection arranged to be detected by the sensor, and the other set consists of holes for paper-end detection arranged to be detected by the sensor when the sheet is exhausted. A hole for gradually detecting the remaining amount of paper is formed at a position between the two sets of holes.

The present invention will be described in detail below with reference to the embodiments shown in the accompanying drawings. FIG. 1 is a diagram showing a main configuration of a detection device according to an embodiment of the present invention. This detection device is applied to the paper feeding device shown in FIGS. The number and arrangement of holes in the detection arm,
And the detection method is different from the conventional example. Therefore, referring to FIG. 5 and FIG. 6 together, the same portions will be denoted by the same reference numerals for description. In the embodiment of FIG. 1, the detection arm 1
Three holes H1, H2, H3 are formed in order from the bottom in 6 and the uppermost two holes H2, H3 form the end area A, and the lowermost hole H1 forms the near end area B. However, the area below the hole H1 is the full area C. The sensor 18 includes a pair of photo interrupters and the like. When a large amount of recording paper or the like (paper) 2 is set, the arm 16 is positioned sufficiently above as shown in FIG. 1, and therefore the sensor 18 detects the full area C and the OF
Although it is F, when the recording paper 2 is consumed and reduced, the position of the upper surface of the recording paper lowers, so that the roller 17 in contact with this lowers, and as a result, the arm 16 also lowers.

FIGS. 2 (a) and 2 (b) are views showing a case where the near end is detected in the embodiment of FIG. 1, and when the amount of the recording paper 2 decreases and approaches the paper end, the hole H1 is detected by the sensor 18. Since it goes inside, the sensor is turned on. After that, when the recording paper further decreases, the arm further descends and the hole H1
Is separated from the sensor 18 and an OFF signal is output to a control unit (not shown). At this time, the control unit determines that it has reached the near end, and displays a message to that effect on the display unit or the like. Then, when the recording paper is further consumed and reaches the paper end, the phenomena shown in FIGS. 3A to 3D sequentially occur within a short time (for example, 1 sec). That is,
When the paper runs out, the lower end of the end area A is located at the sensor 18
At the same time as the sensor 18 detects the hole H2 when entering the inside,
Since the roller 17 falls into the opening 12a, the end area A (holes H2 and H3) passes the sensor 18 in a short time. At this time, the sensor 18 is ON, OFF, ON, OF
A pulse signal such as F is generated. Upon receiving this signal, the control unit determines the paper end and takes necessary measures such as displaying.

Next, FIG. 4 shows another embodiment of the present invention. In this embodiment, a full area C, a large remaining area D, a small remaining area E, and a near end are attached to the detection arm 16 from the lower side. A characteristic is that the area B and the paper end area A are sequentially arranged at predetermined intervals. Except for the full area C, holes (slits) that make up each area D, E, B, A
The number of is increased as it goes upward (it may be decreased).

In the above structure, after the slit in the large remaining amount area D enters and passes through the sensor 18, it is turned on and off.
Since the F signal is output, the control unit determines that the remaining amount is large. Then, when the recording paper is reduced and the two slits in the small remaining amount area E sequentially enter and pass the sensor,
Since the ON, OFF, ON, and OFF signals are output, the control unit determines that the remaining amount is small. Furthermore, near end area B
When the three slits inside pass through the sensor sequentially,
Since the ON, OFF, ON, OFF, ON, and OFF signals are output, the near end is determined, and when the four slits in the paper end area A finally pass the sensor 18, ON, OFF, ON, OFF. , ON, O
Since the FF, ON, and OFF signals are output, the paper end is judged.

[0010]

As described above, according to the present invention, the remaining amount including the detection arm that descends following the decrease in the remaining amount of the recording paper and the sensor for detecting the sensor hole provided in the detection arm. In the detection device, by arranging a plurality of sensor holes in the vertical direction, one sensor can detect not only the paper end but also the near end.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a main part configuration of an embodiment of the present invention.

2A and 2B are diagrams showing a near-end detection procedure.

3A to 3D are diagrams showing a paper end detection procedure.

FIG. 4 is a diagram showing a basic structure of a second embodiment of the present invention.

FIG. 5 is an explanatory diagram of a configuration of a conventional sheet feeding device.

6 (a) and 6 (b) are operation explanatory views of a conventional device.

[Explanation of symbols]

1 paper feed tray, 2 recording paper, 3 axes, 4 half moon roller,
5, 6 gears, 7 motors, 8 corner claws, 10 bottom plates, 11 springs, 12 pedestals, 12a openings, 15 frame bodies, 16 arms, 17 rollers, 18 paper sensors, 19 sensor holes.

Claims (2)

[Claims] 1. A detection arm that is placed on the upper surface of stacked sheets and moves up and down in accordance with the increase and decrease of the position of the upper surface of the sheets.
In a remaining amount detecting device including a sensor for detecting a hole formed in the detection arm, a plurality of the holes are formed in the detection arm in a vertical direction, and the hole is composed of two sets of holes. One set consists of holes for near-end detection arranged to be detected by the sensor when the remaining amount of the paper is near-end, and the other set contains the holes when the paper runs out. A remaining amount detecting device for recording paper or the like, characterized by comprising a paper end detecting hole arranged so as to be detected by a sensor. 2. A detection arm that is placed on the upper surface of stacked sheets and moves up and down in accordance with the increase and decrease of the position of the upper surface of the sheets,
In a remaining amount detecting device having a sensor for detecting a hole formed in the detection arm, a plurality of the holes are formed in the detection arm in the vertical direction, and the hole is composed of two or more sets of holes. , The one set consists of a near-end detection hole arranged so as to be detected by the sensor when the remaining amount of the paper is near end, and the other set is formed when the paper runs out. A hole for detecting the paper end is arranged so as to be detected by the sensor, and a hole for gradually detecting the remaining amount of paper is formed between the two sets of holes. A remaining amount detecting device for recording paper or the like.