JPH09240901A - Sheet material loading device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly perform various processings, and previously prevent the occurrence of a jam or the like by providing a curl quantity detecting means to detect a curl quantity from a height difference between a central part and the front end or the rear end of sheet materials housed in a sheet material loading device to stack and house the sheet materials in order. SOLUTION: A paper sheet printed by a printer main body is guided to discharge roller pairs 1 by passing through a paper sheet carrying passage, and the paper sheet 2 comining out of here stops by striking on a paper sheet stopper 4. At this time, a height of a central part of the loaded paper sheets 2 is detected by a paper sheet height detecting sensor 6. When the fact that the sensor 6 and the paper sheets 2 are put at a prescribed distance or less is detected, a paper sheet discharge part 8 is moved upward by a control device, and a height with the paper sheets 2 is kept almost constant. In this case, a curl quantity detecting sensor 7 is provided to measure a distance up to an object. When a curl quantity having the possibility of causing a jam is detected, a measure such as the paper sheet discharge part 8 is moved upward is taken.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet material stacking apparatus for stacking and storing sheet materials such as paper output from an image forming apparatus such as a printer, a copying machine, a facsimile machine and a printing machine, and more particularly to a curled sheet. The present invention relates to a sheet material stacking device capable of accommodating materials without trouble.

[0002]

2. Description of the Related Art Conventionally, as a stacker (stacking device) for stacking output sheets such as a printer, a stacker as shown in FIG. 2 has been proposed (Japanese Patent Laid-Open No. 3-267268). FIG.
In, the paper 2 output from the discharge roll pair 1 hits the paper stopper 4 and stops, and is stacked on the paper discharge tray 3. Then, when the sheet 2 reaches a predetermined height, it is detected by the sheet height detection sensor 5 and the sheet discharge is stopped.

[0003]

In the conventional stacking apparatus as described above, for example, when the paper 2 is curled, the paper height detection sensor 5 causes the paper height detection sensor 5 to reach a predetermined value before the stacking height of the paper reaches a predetermined value. However, there is a problem in that the sheet discharge is stopped even though there is still room in the sheet discharge tray 3. Further, when the curl is not detected by the paper height detection sensor 5, there is a problem that the front end of the next paper is caught on the curled paper, which causes a paper jam (jam) or reverse order of the paper. It was

An object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a sheet material stacking device capable of surely detecting a curled state and taking appropriate measures.

[0005]

In order to achieve the above object, the present invention relates to a sheet material stacking apparatus for sequentially stacking and storing sheet materials, and a central portion of the sheet materials and a front end or a rear end of the sheet materials. It is characterized in that it is provided with a curl amount detecting means for detecting the curl amount from the difference in height. When the curl amount detecting means detects a curl of a predetermined amount or more, the control means for stopping the discharge of the sheet material, the means for correcting the curl, or the curl correcting control means for strengthening the action, the tray It is characterized in that at least one of the height correction means for increasing the relative height between the sheet discharge section and the sheet discharge section is provided.

With the above-described structure, the present invention can reliably detect the curl state of the paper, and can take various actions such as displaying a warning and stopping the paper discharge. . Further, in the case where the curl correcting unit is provided, the curl can be reduced thereafter by operating the correcting unit when detecting the curl or increasing the correction amount. Further, when the paper discharge unit is configured to be movable up and down with respect to the tray, by raising the paper discharge unit by the amount of the curl, even if the paper is curled, a predetermined amount is set so that a jam does not occur. Can be loaded up to.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a front view showing the configuration of a loading device to which the present invention is applied. The paper printed on the printer body passes through the paper transport path,
It is guided to the discharge roll pair 1. Then, the paper 2 carried out from the discharge roll pair 1 slides on the paper 2 already stacked on the paper discharge tray 3 and hits the paper stopper 4 to stop. The sheet height detection sensor 6 is, for example, an actuator-type photo sensor that includes a light detection lever and detects the position thereof by a photo interrupter. The sheet height detection sensor 6 is attached to a sheet guide 9 integrated with the sheet discharge unit 8 and stacked sheets 2 are stacked. Detect the height of the center of the. Then, when it is detected that the distance between the sensor and the paper is equal to or less than the predetermined distance, the paper discharge unit 8 is moved upward by a predetermined amount under the control of the control device (not shown). By such control, the relative height between the paper discharge unit 8 and the paper 2 is kept substantially constant, and the paper 2 is stacked on the tray 3.

The curl amount detection sensor 7 is, for example, a reflection type photo sensor which emits an infrared pulse and measures the distance to the object by measuring the incident angle or required time of the pulse reflected by the object and reflected. The curl amount detection sensor 7 is attached to a member that moves up and down together with the paper discharge unit 8 above the rear end of the paper in the paper discharge tray 3. Since the position of the trailing edge differs depending on the paper, a plurality of sensors may be provided or the leading edge may be used for measurement. If the paper 2 is curled as shown in FIG. 1, the distance between the curl amount detection sensor 7 and the edge of the paper becomes short. Therefore, when the curl amount that may cause a jam is detected, the paper is Measures such as moving the discharge unit 8 upward are taken.

FIG. 3 is a front view showing the outline of the construction of the stacking apparatus connected to the printer body. For example, a sheet of paper to which toner is attached by a photosensitive drum (not shown) of the printer body is melted by the fuser 9 and fixed on the sheet. At this time, for example, downward curl occurs.
The decurler 10 is composed of a pair of rollers on which a belt is hung and a third roller which is pressed against the belt at an intermediate portion thereof, passes a sheet between the belt and the third roller, and curls generated in the fuser 9. It is a device that straightens the curl by rolling the paper in the opposite direction. Then, the correction amount can be controlled by controlling the pressing strength of the third roller, for example. Decara 10
The sheet that has passed through is turned upside down by the sheet conveyance path 11 of the stacker (stacking device) and is guided to the discharge roll pair 1 of the sheet discharge unit 8.

FIG. 4 is a flow chart showing the curl detection processing in the control device in the printer (not shown).
In step S1, whether the sheets 2 are stacked,
That is, the sheet 2 is delivered from the discharge roll pair 1 and waits until the timing at which the sheet 2 hits the sheet stopper 4 and stops.
This is because the curl amount detection sensor 7 may erroneously detect the presence of curl because the paper is traveling at a high position while the paper is being delivered from the discharge roll pair 1. . In step S2, curl exists, that is, the height is detected by the curl amount detection sensor 7, and it is determined whether or not the curl amount is less than or equal to a predetermined value. When the curl is not detected, the printing process is continued as it is, but when the curl is detected, the process proceeds to step S3. In step S3, the decurler 10 is strengthened. That is, if the decurler 10 has not been activated, the decurler 10 is activated, and if it is already activated, the action is strengthened if there is room to further strengthen the action.

In step S4, it is determined whether or not the paper discharge unit 8 can be moved upward. If the result is negative, no more paper can be stacked, so the printing process is stopped and a warning is displayed. To do. However, if the determination result in S4 is affirmative, in step S5, the paper discharge unit 8 is moved upward by a predetermined amount. In step S6, the curl amount detection sensor again determines whether or not the curl is detected. If the curl is not detected, the printing process is continued, but if the curl is detected, the step S6 is performed again.
Returning to step 4, the processing is repeated. With the above-described structure and processing, it is possible to reliably detect curl and take appropriate measures.

Although the embodiment has been described above, the following modifications are also possible. As an example, the paper discharge unit 8
I disclosed an example where the paper goes up and down, but the paper discharge part is fixed,
The paper discharge tray 3 may be vertically moved. Even if the positions of the paper ejection tray and the paper ejection unit are fixed, curl is detected by measuring the height difference between the central portion and the end portion of the paper to stop the processing and control the decurler. be able to. Although the printer is given as an example, the present invention can be applied to any device as long as it is a device for stacking sheet materials.

Instead of controlling the height of the paper discharge section 8 according to the curl, the paper discharge direction may be controlled. For example, by changing the angle of the surface of the discharge roll pair 1 including the two axes, or by providing a paper guide plate on the output side of the discharge roll pair 1 and changing the angle, the paper discharge direction can be changed. You can When curl occurs, the paper ejection direction is set to be more upward than before, and jamming is prevented.

The curl amount detection sensor may be one that measures the height of the paper and outputs a measurement value corresponding to the height, or the distance to the paper is shorter than a predetermined distance. It may be one that detects that it has become. Further, as the detection method, in addition to the light reflection method, an arbitrary method such as an actuator method or an ultrasonic wave reflection method can be adopted.

[0015]

As described above, in the present invention,
In the stacking device, the curl amount is detected from the difference in height between the central portion of the contained sheet material and the front end or the rear end, and when the curl of a predetermined amount or more is detected, the discharging of the sheet material is stopped. Activate the means to correct the curl,
Alternatively, the action may be strengthened, or the relative height between the tray and the paper discharge unit may be increased. Therefore, there is an effect that it is possible to reliably detect the curled state of the paper, display a warning, stop the paper discharge, and take various other measures. Further, in the case where the curl correcting unit is provided, it is possible to reduce the occurrence of the curl after that by operating the correcting unit when the curl is detected or by increasing the correction amount. There is. Further, when the paper discharge unit is configured to be movable up and down with respect to the tray, by raising the paper discharge unit by the amount of curl, a predetermined amount can be set so that a jam does not occur even if the paper is curled. The effect is that it can be loaded.

[Brief description of drawings]

FIG. 1 is a front view showing a configuration of a sheet stacking apparatus to which the present invention is applied.

FIG. 2 is a front view showing a configuration of a conventional sheet stacking device.

FIG. 3 is a front view showing the configuration of a stacking device connected to the printer body.

FIG. 4 is a flowchart showing a curl detection process in the printer control device.

[Explanation of Codes] 1 ... Ejection Roll Pair, 2 ... Paper, 3 ... Ejection Tray, 4 ... Paper Stopper, 5, 6 ... Paper Height Detection Sensor, 7 ... Curl Amount Detection Sensor, 8 ... Paper Ejection Section, 9 ... fuser, 10 ...
Decara, 11 ... Paper transport path

Claims (4)

[Claims] 1. A sheet material stacking device for sequentially stacking and storing sheet materials, comprising a curl amount detecting means for detecting a curl amount from a difference in height between a central portion of the accommodated sheet materials and a front end or a rear end. A sheet material stacking device characterized by being provided. 2. The sheet material stacking apparatus according to claim 1, further comprising control means for stopping the discharge of the sheet material when the curl amount detecting means detects a curl of a predetermined amount or more. . 3. The sheet material according to claim 1, wherein when the curl amount detecting means detects a curl of a predetermined amount or more, the means for correcting the curl is operated or the action is strengthened. Loading device. 4. The sheet material stacking device sequentially stacks and stores sheet materials regardless of the stacking height of the sheet materials while keeping the relative height between the upper portion of the sheet material and the sheet discharge section constant. Further, when the curl amount detecting means detects a curl of a predetermined amount or more, a height correction means for increasing the relative height between the upper portion of the sheet material and the paper discharge portion is provided. The sheet material stacking device according to claim 1.