JP2002284441A - Paper ejector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paper ejector capable of preventing elimination of stiffness of paper in ejecting, or breakage of a filler, achieving favorable stacking performance, and stabilizing a stacking sheet number regardless of curling states of ejected paper to improve stacking performance. SOLUTION: Spoon-shaped filler parts 6b and 6c are disposed at two positions close to the outer side of a pair of paper delivery rollers 4 for providing stiffness in a perpendicular direction to a carrying direction to paper 1. A back curl detecting sensor 7 to detect if the stacked paper 1 has back curl or not, and full paper detection plate for back curl 6e are provided. When the filler 8 protruded on an upper surface of a bin 5 is pushed by the stacked paper to shield light to the back curl detecting sensor 7 after a detection plate 6d for paper without curl has detected paper full, it is determined that the stacked paper 1 has no curl. When the filler 8 does not shield light to the back curl detecting sensor 7, it is determined that the stacked paper 1 has back curl.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for discharging sheets from an image forming apparatus or the like, and more particularly to a sheet discharging apparatus capable of discharging sheets to a sheet stacking section and improving stacking performance.

[0002]

2. Description of the Related Art A sheet discharging apparatus of this type employs means for detecting a stacking amount of sheets discharged from an image forming apparatus or the like, as in a conventional apparatus disclosed in Japanese Patent Application Laid-Open No. 9-119773, for example. A bar-shaped or spoon-shaped filler portion is hanged from the upper portion of the discharge roller toward the stacked paper in the center portion in a direction orthogonal to the transport direction to detect the height of the upper surface of the stacked paper.

FIG. 1 is a sectional view of an example of a sheet discharging apparatus having a plurality of sheet stacking trays. When the sheet 1 is sent from the image forming apparatus 20 and sent above the sheet discharging device 21 by the pair of conveying rollers 2, the sheet 1 is discharged to a specified sheet stacking tray (hereinafter, referred to as a bin) 5. The switching claw 3 is switched by driving means (not shown), and the sheet 1 is guided to the sheet discharging roller pair 4 of each bin 5, and is discharged onto the bin 5 and stacked.

FIG. 2 is a perspective view showing a conventional full detection type filler portion used in the apparatus shown in FIG. The paper 1 is discharged onto the bin 5 while being crimped, and is stacked by a pair of discharge rollers 4 composed of a discharge roller 4a and a driven roller 4b having a waisted flange. The stiffening is to discharge the paper 1 while squatting at the center of the paper 1 for the purpose of improving the stackability at the time of discharging. In such an apparatus, a spoon-shaped filler portion 6a of the fullness detecting filler 6, which is swingably supported by a method (not shown), is provided near the center of the sheet 1 in a direction orthogonal to the sheet conveying and discharging directions. The filler portion 6a detects the height of the upper surface of the stacked paper 1.

[0005]

As in the configuration of the above-described conventional paper discharge device, the filler portion 6a is hung from the upper portion of the discharge roller pair 4 toward the loaded paper, and the loaded paper 1 is discharged.
When the height of the upper surface of the sheet 1 is detected, the waist attached to the sheet 1 for the purpose of improving the stacking property at the time of sheet ejection is replaced with the filler 6a
However, there is a problem that it disappears when pressed down from above.

[0006] Further, if the weight is reduced so that the filler portion does not cause the waist of the paper 1 to disappear, the strength of the filler portion itself is weakened, which may cause breakage during normal use by the user. There is.

Therefore, in the paper discharging apparatus according to the first aspect of the present invention, the paper is not discharged while preventing the paper from losing its stiffness in the middle of discharging and preventing the filler from being damaged. It is an object of the present invention to improve the stacking performance by stabilizing the number of stacked sheets regardless of the curl state of the sheets.

[0008] In the paper discharge device according to the second aspect,
A further object of the present invention is to stabilize the number of stacked sheets more accurately, thereby further improving the stackability.
The object of the present invention is to improve the operability with an inexpensive configuration, and to provide a paper discharge device according to claim 5 in which a plurality of stacking trays are provided. It is intended to fulfill its purpose.

[0009]

According to a first aspect of the present invention, there is provided a sheet discharging apparatus for receiving a sheet from an image forming apparatus and removing the sheet from the apparatus by a sheet discharging drive roller and a driven roller. A roller section having a pair of rollers for discharging the sheet, a sheet stacking tray for stacking the ejected sheets, a filler section which moves up and down according to the height of the sheets stacked on the sheet stacking tray, and detection linked to the filler section Means for detecting the full height by means of a plate, the filler portion being provided at two locations near the outside of the pair in a direction perpendicular to the paper discharge direction, and the full height of the paper on the paper stacking tray being provided by the detection plate. Means for detecting the rising of the lower surface of the bundle of sheets stacked on the sheet stacking tray below the filler portion, and Flip and characterized by having a means for changing the full height of the sheet in the sheet stacking tray.

According to a second aspect of the present invention, in order to achieve the above object, in the paper discharging apparatus according to the first aspect, the floating amount detecting means detects the floating amount of the lower surface of the stacked sheet bundle. The full height changing means changes the full height according to the detected floating amount information.

According to a third aspect of the present invention, in order to achieve the above object, in the sheet discharging apparatus according to the first or second aspect, the detecting member for detecting the presence or absence of a sheet on the sheet stacking tray has a full height. In the changing means.

According to a fourth aspect of the present invention, in order to achieve the above object, in the paper discharging apparatus according to the first or second aspect, the means for counting the number of sheets discharged onto the sheet stacking tray is provided. The full height changing means is provided.

According to a fifth aspect of the present invention, in order to attain the above object, the paper discharging apparatus according to any one of the first to fourth aspects has a plurality of the paper stacking trays.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. In the following, portions common to the related art are denoted by the same reference numerals, and redundant description is omitted. FIG. 3 is a perspective view (A) and a cross-sectional view (B) showing a first embodiment of the paper discharge device according to the present invention. In the present embodiment, similarly to the conventional example, the paper 1
The paper 1 is discharged onto the bin 5 while being seated, and stacked. Two spoon-shaped filler portions 6b and 6c are provided, and are disposed at two places near the outer side of the paper discharge roller pair 4 for stiffening, not at the center of the paper 1 in a direction orthogonal to the transport direction of the paper 1. I have. With this arrangement, the stiffening can be further strengthened without eliminating the mountain due to the stiffening at the center of the sheet 1. A back curl detecting mechanism and a full curl detecting position for back curl are added on the bin 5.

[0015] Even if the number of sheets 1 loaded in the bin 5 is the same, the height at which the sheets 1 become full differs significantly depending on the state of curl. In particular, when the stacked paper 1 is back-curled, the space A is generated between the bin 5 and the stacked paper, which affects the full height. Therefore, in order to detect whether the loaded paper 1 has a back curl or no curl,
A back curl detection sensor 7 and a back curl full detection plate 6e are provided.

As shown in FIG. 4, after the curl-free detecting plate 6d detects the full state, the rotatable filler 8 protruding from the upper surface of the bin 5 is pressed by the stacking paper, thereby causing the back curl detecting sensor 7 to move. When shaded, the stacked paper 1
Is determined to have no curl, and the job is terminated. On the other hand, as shown in FIG. 3B, when the filler 8 does not shield the back curl detection sensor 7, the loaded paper 1 is determined to have a back curl, and the back curl full detection plate 6d
Is checked, and if it is OFF, the stacking is continued, and the job is ended when it is turned ON. The state shown in FIG. 4 occurs when there is no curl or when face curled paper is used.

FIG. 5 shows a flowchart of a fullness detecting operation in the apparatus of this embodiment. First, the rotation of the drive system motor (not shown) turns on the switching claw 3 of the bin 5 to be discharged (step 2), and discharges and stacks the paper 1 (step 3). Transport sensor is O
If N (step 4), the above-described full-curl detection is performed until full detection (step 5). When full is detected, back-curl detection is performed (step 6), and full-curl detection for back-curl is turned on. Step 3 and the subsequent steps are repeated (Step 7), and when turned on, the drive system motor is stopped (Step 8), and the discharged bin 5
The switching claw 3 is turned off (step 9), and the job ends.

FIG. 6 shows a second embodiment of the sheet discharging apparatus according to the present invention.
FIG. 2 is a cross-sectional view showing the embodiment. In the present embodiment, the distance measuring sensor 9 is provided in the back curl detecting sensor unit, the height h of the space A is measured, and the full detection positions (10a to d...) Are obtained based on the information of the distance measuring sensor 9. Variable. That is, fullness is determined based on the thickness t of the stack of sheets to be stacked. And after the first full detection sensor 10a detects full,
The distance measuring sensor 9 is checked, and the full detection positions 10a to 10d are determined based on the information of the distance measuring sensor 9 based on the preset number N of stacked sheets (thickness t of the stacking bundle), and the stacking is performed to that position. continue.

FIGS. 7A and 7B are cross-sectional views showing a third embodiment of the sheet discharging device according to the present invention. In the present embodiment, the fullness detection filler 6 has a configuration in which the fullness detection of the paper on the paper stacking tray 5 is provided and a unit for detecting the presence or absence of the paper is provided.

First, the detection plate 6f of the full detection filler 6
Thus, the fullness detection sensor 11 is configured to shield light, and the paper presence / absence sensor 12 for detecting the presence or absence of paper on the bin 5 is configured to shield light. Of course, the fullness detection filler 6 may be provided with a detection plate for paper presence detection separately from the fullness detection plate 6f. On the other hand, when no paper is loaded on the bin 5, the detection plate 6f detects the presence or absence of the paper while the spoon-shaped filler portions 6b and 6c of the full detection filler 6 are inserted into the groove 5a of the bin 5. Presence sensor 12
Is shielded from light, and a paper-out state is detected.

When the first sheet 1 is loaded on the bin 5 as shown in FIG.
The spoon-shaped filler portions 6b and 6c are pushed up and rotated by the paper 1 and come out of the groove 5a of the bin 5, and the detecting plate 6f (or the detecting plate for detecting the presence or absence of the paper) is moved from the paper presence sensor 12 by the operation. Detach and detect paper presence.

FIG. 8 shows a fourth embodiment of the sheet discharging apparatus according to the present invention.
FIG. 2 is a cross-sectional view showing the embodiment. The present embodiment has a configuration in which the fullness detection filler 6 detects the fullness of the paper 1 on the bin 5 and includes means for counting the number of papers 1 discharged onto the bin 5.

That is, the detection plate 6 of the full detection filler 6
The g sensor blocks the fullness detection sensor 11 and shields the sensor 13 that counts the number of sheets on the bin 5 from light. The fullness detecting filler 6 may be provided with a detecting plate for counting sheets separately from the detecting plate 6g for detecting the fullness. The counting of the number of sheets 1 is performed when the filler portions 6b and 6c of the full detection filler 6 are lifted when the sheet 1 is discharged, and the detection plate 6g shields the sensor 13 for counting the number of sheets, and the number of sheets is counted. It has a configuration. When the sheet 1 is ejected by the sheet ejection roller pair 4, the sheet is ejected with the sheet ejection roller pair 4 squatting on the sheet. Therefore, the sensor 13 detects the filler portions 6b and 6c of the fullness detection filler 6 by the sensor 13. The bottom surface is lifted by the sheet 1 to a sheet discharge opening (not shown), and at this time, the detection plate 6g is provided at a position where the detection plate 6g rotates for counting the number of sheets.

With this configuration, when the user discharges the sheet to the sheet discharge device, the user can know how many sheets are currently loaded on the sheet loading tray to be discharged by the count number of the immediately preceding job. it can. The user can select whether to discharge the paper to the selected paper loading tray, not to discharge the paper, or discharge the paper to another paper loading tray, thereby improving the operability of the user.

FIG. 9 is a flowchart showing the operation of the above-described fourth embodiment. First, the paper presence sensor 12 is turned on.
Then (Step 1), the number N of stacked bins 5 for discharging the paper 1 is displayed to the user by an appropriate means such as an operation panel (Step 2), and the designation of the bin 5 as the discharge destination is specified by the user. If not, the job is terminated. If the paper is to be discharged (step 3), the switching claw 3 of the bin 5 to be discharged is rotated by rotation of a drive system motor (not shown) (step 4).
Is turned on (step 5), the number of sheets is counted (step 6), and the sheets 1 are discharged and stacked (step 7).
If the sheet conveyance sensor (not shown) is ON (step 8), the above-described full-curl detection without curl is performed until the full is detected (step 9). When full is detected, back-curl detection is performed (step 10). Step 6 and subsequent steps are repeated until the full-curl detection is turned on (step 11), and when it is turned on, the drive system motor is stopped (step 12), and the switching claw 3 of the discharged bin 5 is turned off (step 11). 13) End the job.

[0026]

As described above, the paper discharge device according to the first aspect of the present invention does not cause the waist attached to the paper being discharged to disappear and prevent the filler from being damaged.
In addition to providing good stackability, there is an effect that the stackability can be improved by stabilizing the number of stacked sheets regardless of the curl state of the discharged paper.

According to a second aspect of the present invention, there is provided a sheet discharging device.
In addition to the above-mentioned common effect, there is an effect that the stacking property can be further improved by stabilizing the number of stacked sheets accurately.

According to a third aspect of the present invention, there is provided a sheet discharging apparatus.
In addition to the above-mentioned common effects, by providing a detection member for detecting the presence or absence of a sheet on the sheet stacking tray in the full height detection member, there is an effect that operability can be improved with an inexpensive configuration.

According to a fourth aspect of the present invention, there is provided a sheet discharging device.
In addition to the above-mentioned common effects, by providing a means for counting the number of sheets discharged to the sheet stacking tray in the full height detection member, the operability can be further improved with a low-cost configuration. is there.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an example of a sheet discharge device having a plurality of sheet stacking trays.

FIG. 2 is a perspective view showing a conventional full detection type filler portion used in the apparatus as shown in FIG. 1;

FIG. 3 is a perspective view (A) and a cross-sectional view (B) showing a first embodiment of a sheet discharging device according to the present invention.

FIG. 4 is a sectional view showing the operation of the embodiment device of FIG. 3;

FIG. 5 is a flowchart of a fullness detection operation in the embodiment device of FIG. 3;

FIG. 6 is a cross-sectional view illustrating a second embodiment of the paper discharge device according to the present invention.

FIG. 7 is a cross-sectional view showing a third embodiment of the paper discharge device according to the present invention.

FIG. 8 is a sectional view showing a fourth embodiment of the paper discharge device according to the present invention.

FIG. 9 is a flowchart showing the operation of the fourth embodiment.

[Explanation of symbols]

 Reference Signs List 1 paper 2 transport roller pair 3 switching claw 4 paper discharge roller pair 4a paper discharge roller 4b driven roller 5 paper loading tray (bin) 5a groove 6 fullness detection filler 6a filler part 6b, 6c filler part 6d detection plate 6d for curlless 6e Back curl full detection plate 6f Detection plate 6g detection plate 7 Back curl detection sensor 8 Filler 9 Distance measuring sensor 10a to 10d Full detection position 11 Full detection sensor 12 Paper presence sensor 13 Sensor 20 Image forming device 21 Paper ejection device

Claims (5)

[Claims] An image forming apparatus includes: a pair of rollers for receiving a sheet from an image forming apparatus and discharging the sheet out of the apparatus by a discharge driving roller and a driven roller; and a sheet stacking tray for stacking the discharged sheet. A filler portion that moves up and down in accordance with the height of the paper stacked thereon, and a unit that detects a full height by a detection plate that is interlocked with the filler portion, wherein the filler portion is provided in a direction orthogonal to a paper discharging direction. Means for detecting the full height of sheets on the sheet stacking tray by the detection plate, and a lower surface of a sheet bundle stacked on the sheet stacking tray below the filler portion, at two locations near the outside of the pair. It is characterized in that it has means for detecting uplift, and means for changing the full height of sheets on the sheet stacking tray according to the detection result of the uplift detection means. Paper discharge device. 2. The sheet discharging apparatus according to claim 1, wherein said floating amount detecting means detects a floating amount of a lower surface of said stacked sheet bundle, and said full height changing means detects said detected floating amount information. A paper discharge device characterized in that the full height is changed according to the condition. 3. The sheet discharging device according to claim 1, wherein a detecting member for detecting the presence or absence of a sheet on the sheet stacking tray is provided in the full height changing means. 4. The sheet discharging apparatus according to claim 1, wherein a means for counting the number of sheets discharged onto the sheet stacking tray is provided in the full height changing means. apparatus. 5. The sheet discharging apparatus according to claim 1, wherein said sheet stacking tray has a plurality of stages.