JPH07206250A - Paper storage device - Google Patents

Abstract

PURPOSE:To align paper loaded on a tray well without shifting paper even if the paper has a curled part in it, and discharge the paper smoothly. CONSTITUTION:A pair of detection sensors 14a, 14b are disposed at a prescribed distance in the orthogonal direction to the discharging direction of paper discharged from an image forming device to detect the displacement of the front surface (loaded surface) of the paper 3 loaded on a tray 1. A tray inclining mechanism which inclines the tray in the orthogonal direction to the discharging direction of the paper is provided. When it is detected that one surface in the side direction of the paper is curled and standing, one of a pair of right and left lifting motors 5a, 5b which constitutes the tray inclining mechanism is driven to incline the tray 1 and keep the loaded surface horizontal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet accommodating apparatus for accommodating sheets ejected from an image forming apparatus such as a copying machine on a tray which can be moved up and down, and is stable especially when a large amount of sheets are stacked. The present invention relates to a sheet storage device capable of performing the aligned sheet alignment.

[0002]

2. Description of the Related Art As a conventional sheet accommodating apparatus for stacking and accommodating sheets ejected from an image forming apparatus on a tray, one disclosed in Japanese Patent Application Laid-Open No. 2-56359 is known. This device detects the stacking amount of sheets stacked on the tray, raises and lowers the tray, and maintains the tray at an appropriate height according to the stacking amount of sheets. According to this proposal, the tray can be moved up and down according to the amount of paper loaded on the tray, and the upper surface of the loaded paper can always be maintained at an appropriate height.

[0003]

However, according to the conventional sheet accommodating apparatus constructed as described above, when a large amount of sheets are stacked on the tray, one side of the sheets is curled due to moisture or the like. In that case, the loading surface is inclined. That is, when the paper 3 discharged by the discharge roll 2 is curled on the tray 1 that moves up and down as shown in FIG. Is higher than the left side. In many cases, this curl absorbs moisture from only one direction in one bundle of paper and occurs only on one side. When the paper 3 is curled in one direction as described above, the stacking surface on the upper surface of the paper 3 stacked on the tray 1 is inclined. As a result, there are problems that the sheets 3 on the tray 1 cannot be properly aligned, and the sheet 3 to be ejected next is caught on the stacking surface and cannot be ejected normally. It is an object of the present invention to provide a sheet storage device that can satisfactorily align sheets stacked on a tray without misalignment and can smoothly discharge the sheets.

[0004]

In order to achieve the above object, the present invention provides a sheet accommodating apparatus for accommodating and ejecting sheets ejected from an image forming apparatus on a tray that can be raised and lowered.
It is characterized by having the following configuration. That is, the sheet accommodating apparatus according to claim 1 is arranged at a predetermined interval in a direction perpendicular to the sheet ejection direction, and at least two detecting means for detecting the stacking surface of the sheets stacked on the tray, Based on tilting means for tilting the tray in a direction perpendicular to the paper discharge direction and tilt information of the paper stacking surface detected by the detecting means, the tilting means is controlled so that the paper stacking surface becomes horizontal. And a control means. According to another aspect of the present invention, there is provided a sheet accommodating apparatus in which a tray is tilted in a direction perpendicular to a sheet discharging direction, and the sheet is stacked based on the sheet type information and the number of sheets stacked on the tray. A control means for calculating the angle of the tray whose surface is horizontal and controlling the tilting means in accordance with the calculated tray angle is provided.

[0005]

According to the sheet accommodating apparatus of the present invention, the detecting means detects the stacking surface of the sheets stacked on the tray, and the tilting means is driven by the control means to keep the stacking surface horizontal. To do. According to the sheet accommodating apparatus of the second aspect, the control unit loads the sheets stacked on the tray based on the size, thickness, curl amount information due to moisture absorption and the number of stacked sheets. The tilt angle of the stacking surface of the paper is calculated, and the tilting means is driven based on the calculated angle to keep the stacking surface horizontal.

[0006]

EXAMPLES Examples of the present invention will be described below. 1 and 2 show the configuration of the first embodiment of the present invention. The parts of this embodiment shown in each drawing corresponding to the parts of the conventional example shown in FIG. 5 are denoted by the same reference numerals. On the base 4, a right elevator motor 5a and a left elevator motor 5b as a pair of left and right tilting means are respectively provided with drive shafts 6a and 6b.
Are fixed in a vertical direction. Drive shaft 6
Pulleys 7a and 7b are attached to a and 6b, respectively. In addition, the base 4 has support portions 4a. A pair of lead screws 8a and 8b are rotatably supported in the vertical direction via 4b. Lead screw 8a, 8b
Pulleys 9a and 9b are attached to the lower ends of, respectively. Between the pulleys 7a and 9a and between the pulleys 7b and 9
Belts 10a and 10b are stretched between b.

One ends of horizontal elevating arms 11a and 11b are screwed into the lead screws 8a and 8b, respectively. On the other hand, on the lower surface of the tray 1, a pair of left and right connecting portions 12
a and 12b are fixed, and the connecting portions 12a and 12b are rotatably connected to the elevating arms 11a and 11b via pins 13a and 13b attached in the horizontal direction. Here, one pin 13a is connected to one connecting portion 12
The pin 13b is rotatably connected to the round hole formed in a, and the other pin 13b is inserted into the long hole formed in the other connecting portion 12b.

A plurality of pairs of discharge rolls 2 are provided in the horizontal direction on the upper part of the base 4, and the paper 3 discharged from the main body of the image forming apparatus (not shown) is discharged onto the tray 1 and stacked and accommodated. Further, on the upper part of the base 4, a predetermined interval is provided at a right angle with respect to the discharge direction (arrow direction in FIG. 2) of the paper 3, and at least the stacking surface of the paper stacked on the tray is detected. Two detection means are arranged. In this example, the right height sensor 14a as a pair of left and right detecting means
And the left height sensor 14b are arranged. The height sensors 14a and 14b are detection units 15a and 15b, respectively, which have a light emitting unit and a light receiving unit (not shown) provided so as to face each other.
And sensing arms 17a and 17b rotatably supported via support shafts 16a and 16b.

One end of each of the sensing arms 17a and 17b is in contact with the stacking surface of the upper surface of the sheets 3 stacked on the tray 1, and the other end of the sensing arms 17a and 17b serves as a light emitting portion and a light receiving portion when the stacking surface is at a predetermined height. It is located between them and blocks light. Height sensor 1
The height information of the loading surface detected by 4a and 14b is
C is input to the CPU 21 as the control means shown in FIG.
A control signal based on the motor drive control amount calculated by the PU 21 is output to the drive circuits 23 and 24 to drive the right elevator motor 5a and the left elevator motor 5b so that the loading surface becomes horizontal.

FIG. 4 shows a processing flow of the control means. When the discharge is started, the sheets are stacked on the tray, and the stacking amount is judged by the change of the height sensor from OFF to ON (height sensor ON) (S100). If the stack is changed from OFF to ON, the elevator motor is moved. Is driven to lower the tray (S101). Next, turn the height sensor ON → OFF
The operation (height sensor OFF) is judged (S102), and O
When it becomes FF, the drive of the elevator motor is stopped (S103). Then return to step 100,
Continue to load paper. By repeating this operation, a large amount of paper is loaded on the tray.

When the tray is not at the position where the paper can be discharged, the tray is first raised to a predetermined position. That is, while the height sensor is OFF after the sheet discharge is started, that is, when the change of the height sensor to ON is not determined in step 100, a certain time is waited (S104), and then the elevator motor is driven to raise the tray. . Height sensor O
The change from FF to ON is judged (S106), the elevator motor is stopped at the time of the change to ON, and step 1
The process returns to 00 and the sheets are stacked.

Next, the operation of the first embodiment will be described. When the stacking surface of the upper surface of the sheets 3 discharged by the discharging roll 2 and stacked on the tray 1 is horizontal and is at a predetermined height position, the upper ends of the arms 17a and 17b of the height sensor 14 are the detection units. It is located inside 15a and 15b to shield light. At this time, the height sensor outputs an OFF signal. On the other hand, discharge of the paper 3 by the discharge roll 2 proceeds,
When both arms 17a and 17b rotate clockwise in FIG. 2, the light shielding of the detection units 15a and 15b is released. At this time, the height sensor outputs an ON signal.

When the ON signal of the height sensor is input to the CPU 21, both the elevator motors 5a and 5b are rotationally driven, and the lead screws 8a and 8b and the lifting arm 1 are moved.
The tray 1 descends via 1a and 11b. When the height of the stacking surface on the tray 1 reaches a predetermined position, the detection unit 1
The lights 5a and 15b are shielded again, and the elevator signals 5a and 5b are stopped by the OFF signal at this time. In addition,
This control is performed at a timing when the information on the tray stacking surface is obtained, and is controlled not to be performed while the sheet 3 is being discharged by the discharge roll 2. In this way, when the stacking surface is horizontal, the stacking surface of the sheets 3 is always at a predetermined position, and good sheet alignment can be obtained.

As shown by the chain double-dashed line in FIG. 1, when the left side is curled upward in a direction perpendicular to the discharge direction of the paper 3, for example, the left side is a predetermined stacking surface of the paper 3. Even if the detection unit 15a is in the position of
The light blocking of 5b is released. When this signal is input to the CPU 21, only the left elevator motor 5b is rotationally driven, the left side of the tray 1 is lowered via the lead screw 8b and the elevating arm 11b, and the tray 1 is moved as indicated by the chain double-dashed line. Incline. When the curl surface reaches a predetermined position, the detection unit 5b is shielded from light and the rotation of the elevator motor 5b is stopped via the CPU 21. As a result, the stacking surface of the sheets 3 can always be kept horizontal, and good sheet alignment can be obtained. Even when the right side of the paper 3 is curled, good paper alignment can be obtained by the same operation.

In the above embodiment, the case where the height sensor 14 is two has been described. However, when the size of the paper 3 is large, three or more height sensors 14 may be provided. Or height sensor 1
4 may be movable in the lateral direction, and the position may be changed according to the size of the sheet 3. Further, the height sensor 14 is not limited to the photoelectric method, and for example, a proximity switch or the like may be used. Further, when the number of stacked sheets of paper 3 is small, the influence of curling is small, so the above control may be started after a predetermined number of sheets of paper 3 are stacked.

In the above embodiment, the trays are lowered by a certain distance so that the stacking surface becomes horizontal by the ON-OFF signals of the two sensors detected by the state of the stacking surface of the paper. When a detecting means of a method of detecting the change of the loading surface by a voltage value is used, the correspondence relation between the detection value from the height sensor and the loading height is stored in the memory (ROM) 22 in advance, and the CPU 21 Calculates the loading height based on the input detection signal, and when the loading height reaches a predetermined value, the elevator motors 5a, 5
Drive b to lower the tray by a certain distance. It is also possible to calculate the inclination of the tray based on the detection signal input at this time, change the drive control amount of the elevator motors 5a and 5b according to the inclination, and incline the tray so that the stacking surface becomes horizontal. .

FIG. 5 shows the configuration of the second embodiment of the present invention. In this embodiment, the height sensor 14 in the first embodiment is omitted, and the CPU 21 uses the size information of the sheets 3 and the number information of the sheets 3 stacked on the tray 1 and the data of the tray lowering amount with respect to the size. The angle of the tray 1 on which the stacking surface 3 is horizontal is calculated, and the inclination angle of the tray is controlled based on the calculation result. Here, the elevator motor 5a as the tray tilting means,
5b and the tray tilting mechanism have the same structure as in the first embodiment.

The storage unit attached to the CPU stores paper information such as the number of sheets, the data of the tray lowering amount with respect to the size, the number of sheets information, and the size information as the information sent from the main body. The CPU 21 calculates the tray descent amount based on the number-of-sheets information and the size information, obtains the drive control amount of the elevator motor from this tray descent amount, operates each drive circuit, and controls the tray ascent and descent.
FIG. 6 shows the relationship between the descending amount of the tray and the number of discharged sheets.
Fig. 6 (1) shows elevator control based on the number of sheets,
FIG. 6 (2) shows elevator control based on size information.

In the case of the number-of-sheets information, the height of the stacking surface of the upper surface of the sheets 3 stacked on the tray and the inclination displacement of the sheets in the side direction are calculated from the input number-of-sheets information and the data of the tray lowering amount. Elevator motor 5 from the calculation result
The control amounts of a and 5b are obtained, and the respective motors are driven to lower the tray by a certain distance. At this time, when the stacking surface is tilted, the tray is tilted by a predetermined angle to make the stacking surface horizontal as in the first aspect of the invention.

In the case of size information, the height of the stacking surface of the upper surface of the paper 3 stacked on the tray and the inclination displacement of the paper in the side direction are calculated from the input size information, the number of sheets information and the data of the tray lowering amount. Calculation is performed, and the control amounts of the elevator motors 5a and 5b are calculated from the calculation results, and the respective motors are driven to lower the tray by a certain distance.
As shown in FIG. 6B, when the number of ejected sheets is the same, the tray lowering amount is large when the paper size is large, and is small when the paper size is small.

[0021]

As described above, according to the invention described in claim 1, since the tray is tilted so that the stacking surface of the sheets stacked on the tray becomes horizontal,
Even when a large amount of curled paper is stacked on the tray, the paper can be aligned well without shifting.
Moreover, the generated curl does not project into the paper discharge area, and the paper can be discharged smoothly. Further, according to the second aspect of the present invention, the configuration of the stacking surface of the sheets is calculated based on the sheet type information and the stacked sheet number information, and the inclination of the tray is controlled based on the calculation result. By detecting the loading surface of No. 2 by software processing, a mechanism such as a height sensor is not required, and the structure can be simplified.

[Brief description of drawings]

FIG. 1 is a rear view showing the configuration of an embodiment of a first invention of a sheet storage device of the invention.

FIG. 2 is a side view of FIG.

FIG. 3 is a block diagram showing a configuration of a control system according to an embodiment of the first invention.

FIG. 4 is a diagram showing a processing flow of elevator control by a control means.

FIG. 5 is a block diagram showing a configuration of a control system according to an embodiment of a second invention of the sheet storage device of the invention.

FIG. 6 is a diagram showing the relationship between the tray descent amount and the number of discharged sheets.

FIG. 7 is an explanatory diagram showing a problem of an example of a conventional sheet storage device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Tray, 2 ... Ejection roll, 3 ... Paper, 5 ... Elevator motor, 14 ... Height sensor, 21 ... CPU (control means), 22 ... Memory (ROM), 23, 24 ... Drive circuit

Claims (2)

[Claims] 1. A paper accommodating device for stacking and accommodating paper discharged from an image forming device on a tray that can be moved up and down, and is arranged at a predetermined interval in a direction perpendicular to the paper discharge direction, At least two detecting means for detecting the stacking surface of the sheets stacked on the sheet, tilting means for inclining the tray in a direction perpendicular to the discharge direction of the sheets, and stacking of the sheets detected by the detecting means. A sheet accommodating apparatus comprising: a control unit that controls the tilting unit so that the stacking surface becomes horizontal based on surface inclination information. 2. A paper accommodating device for accommodating and ejecting paper ejected from an image forming apparatus on a tray which can be raised and lowered, and tilting means for inclining the tray in a direction perpendicular to a paper ejection direction. Based on the type information and the information on the number of sheets stacked on the tray, a control means for calculating the angle of the tray at which the stacking surface of the sheets is horizontal and controlling the tilting means according to the calculated tray angle. A sheet storage device comprising: