JPS62201768A - Sheet sorting device - Google Patents

Abstract

PURPOSE:To make it possible to load a large amount of sheets in order, by supporting the rear end of sheets which are loaded exceeding the wall part of a tray after the completion of descent of the tray, by means of a projecting part formed on a sorting device body. CONSTITUTION:Sheets which are sorted by sorting rollers 6, 9 and discharged onto a tray 4, are supported at its trailing edge by a tray wall section 50, and are therefore loaded. Further, when the loaded amount of the sheets increases so that tray 4 supported by spring 20 is lowered by a predetermined amount (k), by its dead weight of the tray 4, the discharged sheets are loaded exceeding the wall part 50 of the tray 4. However, since a convex part 69 formed on the sheet discharge side cover 17 for a sorting device is disposed flush with a cut-off recess 51 in the wall section 50, and therefore the trailing edges of the sheets which are loaded exceeding the wall section 50 are supported by the convex part 60. Thus, the sheets are not deformed due to the descent of the tray while they do not slip from each other, thereby it is possible to load a large number of sheets in order.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a sheet sorting device that is attached to an image forming apparatus such as a copying machine, a printing machine, or a page printer.

[Conventional technology]

Conventionally, for sheet R sorting used in image forming apparatuses such as copying machines, printing machines, and page printers, the following configuration has been proposed as a tray in the apparatus, for example, in Japanese Utility Model Publication No. 56-10751. . That is, the tray is equipped with a tray body and a bottom plate on which sheets discharged from the sorter body are loaded, and the bottom plate is rotatably supported by the tray body at its leading edge in the sheet discharge direction. The rear portion is elastically supported so as to be gradually lowered by the weight of the loaded sheet. Furthermore, the bottom plate is tilted so that the tip side in the sheet ejection direction is higher than the initial state, and the ejected sheet falls while sliding on the slope of the bottom plate, and the trailing edge is attached to the tray body or the sorter to which the tray is attached. It is known that the device is configured to be loaded in contact with the wall of the device body.

[Problem that the invention seeks to solve]

By the way, in general, as image forming apparatuses become faster, the speed of sheet ejection increases, causing problems such as ejected sheets flying out of the tray or stopping halfway on the slope of the ejection jet bottom plate. The above-mentioned problem is prevented by increasing the slope.

In the tray with the conventional structure described above, for this purpose, the inclination of the bottom plate in the sheet ejection direction is made thicker (if the rear end of the sheet comes into contact with it, the tray body or the sorter is The force becomes large, and the frictional force generated at the contact area causes the bottom plate to not lower even when sheets are stacked on the bottom plate, resulting in sheets overflowing and scattering, and even if the bottom plate falls, the bottom plate does not lower. The edge of the tray body or the sorter does not go down due to the frictional force with the wall of the device, and therefore the central portion of the stacked sheets in the discharge direction becomes concave, resulting in problems such as uneven stacking of sheets.

In order to improve this drawback, the inventors of the present invention integrally formed the wall surface 70 that abuts and supports the rear edge of the stacked sheet 72 with the tray bottom surface 71, as shown in FIG.
When a structure was adopted in which the wall surface 70 descended together with the bottom surface 71 due to the weight of 2, although the above-mentioned drawback was solved, another problem occurred.

In other words, the upper end position of the sheet support wall surface 70 in contact with the trailing edge of the sheet must be at a position lower than the sheet discharge lower 3 of the main body of the apparatus for sorting when no sheets are loaded and the tray is not lowered. Therefore, the height of the wall surface 70 cannot be increased very much, resulting in a problem that the number of sheets stacked cannot be increased. Furthermore, if the trailing edge of the sheet is to be supported not only on the tray wall surface 70 but also on the wall 74 of the main body of the sorting apparatus, the leading edge of the stacked sheet 72 at the boundary part will be held at m as shown in FIG.
Moreover, the sorting M standard is also in an unfavorable state because it suddenly shifts in the middle of the stacked sheets.

The present invention has been made in order to solve the above-mentioned problems in the conventional sheet sorting device and the structure proposed by the inventors of the present invention. The object of the present invention is to provide a sheet sorting device equipped with a tray that can stack a large amount of sheets in an orderly manner without causing deformation of the stacked sheets.

[Means and operations for solving the problems] In order to solve the above problems, the present invention provides sorting at the bottom surface rising in the direction of sheet discharge from the apparatus main body, and at the rear of the discharge sheets. A discharge sheet stacking tray integrally formed with a wall surface that abuts and supports edges, and the tray is gradually lowered by the weight of the stacked sheets, and the lowering operation is performed so that the height of the stacked sheets exceeds the height of the wall surface of the tray. The tray elastic support means previously set to be completed, and the Ha
The protrusions arranged on the main body and the sheet [sorting is provided in the device.

With this configuration, when the tray is in a state where it can be lowered, the trailing edge of the ejected sheet is supported by the wall of the tray, and after the tray has finished lowering, the trailing edge of the stacked sheet extends beyond the wall of the tray. Since the edge is supported at the same position as the wall surface by a protrusion provided on the main body of the sorting device, in any case, the trailing edge of the sheet and its support member do not move relative to each other, and therefore the tray The lowering is controlled only by the weight of the loaded sheets and is performed smoothly, and the lowering action does not cause deformation of the sheets or shift of the loaded sheets, making it possible to stack a large number of sheets in an orderly manner. .

〔Example〕

Hereinafter, the present invention will be described in detail based on illustrated embodiments. FIG. 1 is a perspective view showing a state in which a sheet sorting apparatus 2 according to the present invention is installed in an image forming apparatus 1 such as a copying machine, a printing machine, or a page printer. The sorting apparatus 2 consists of an apparatus main body 3 and a tray 4, and is fixed to the image forming apparatus 1 with a mounting bracket (not shown). For this sorting, the apparatus 2 is configured to receive signals from the image forming apparatus 1 in this embodiment and control the sorting of discharged sheets. , the number of ejected sheets may be counted and sorted according to a preset number.

FIG. 2 is an enlarged sectional view of the sorting device 2, with some parts omitted. In the figure, reference numeral 5 denotes a main body frame, and a driven roller 6 for sorting along the sheet conveying path 10 is attached to the frame 5 so as to be rotatable about a support shaft 36 substantially perpendicular to the conveying direction. On the other hand, a sub-frame 7 is rotatably attached to the main body frame 5 around a support shaft 8, and a sorting drive roller 9 is installed on the sub-frame 7 substantially perpendicular to the conveying direction of the ejected sheets. It is rotatably attached around a support shaft 26 that is coaxial with the rotation support shaft 36 of the driven roller 6 . The sorting drive roller 9 forms a pair with the sorting driven roller 6, and the sorting rollers cooperate with each other.

An upper sheet conveyance guide 11 is provided on the subframe 7 side along the sheet conveyance path 10, while a lower sheet conveyance guide 12 is fixedly provided to the main frame 5 opposite to the upper sheet conveyance guide 11. There is.

Both conveyance guides 11°12 are located across the sheet conveyance path lO.
A sheet detector consisting of an LED 13 and a phototransistor 14 is provided on the outside of the sheet conveyance guide 11.12, and the passage of the sheet can be detected through the through holes provided in both sheet conveyance guides 11 and 12.

Guide pins 15 are fixed to support members 16 that support the lower sheet m transport guide 12 on both sides of the lower sheet transport guide 12 on the sheet transport side so as to protrude into the sheet transport path lO. Note that this support member 16 is fixed to the main body frame 5.

In the tray 4, a tray holding portion 18, which is integrally formed with the tray 4 and is formed to protrude from a hole formed in the sheet discharge side cover 17, is inserted into a tray holding member 19 disposed within the main body frame 5. It is configured to be fixed by this. The tray holding member 19 has guide rollers (
(see FIG. 11), and is urged upward by a spring 20 whose one end is hung on the main body frame 5 and the other end is hung on the tray holding member 19.

FIG. 3 is an enlarged perspective view showing a portion of the sorting roller in detail. The sorting drive roller 9 is pivotally supported by fitting both ends of the roller shaft 21 into bearings 23 provided on the frame A22. A drive motor 24 is provided on one side of the frame A22, and a gear train 25 is provided.
The number of rotations and the direction of rotation are adjusted by rotating the drive roller 9 for sorting. Further, a support shaft 26 is fixed to the frame A22 by caulking or the like.
6 is coaxially and rotatably supported by the subframe 7 with its axis aligned with a support shaft 36 to be described later.

A spring A27 is attached to the end of the arm 22a of the frame A22.
is applied, and during constant sorting, the drive roller 9 is biased to face in a certain direction. Further, a stopper pin A2B is provided on the arm 22a, and the stopper pin A2B is inserted into an arc-shaped hole that regulates the swing range of the stopper pin A28 provided on the subframe 7 (not shown).
8, and the direction of the drive roller 9 is set by abutting stopper pins A28 against both end surfaces of the roller.

Further, one end of a link 29 is rotatably attached to the arm 22a by a pin 30, and the other end of the link 29 is attached to a plunger 31' of a solenoid 31 fixed to the subframe 7.

The sorting driven roller 6 is disposed opposite to the driving roller 9. At both ends of the sorting driven roller 6, stiffened rollers 32 having a slightly larger diameter than the sorting driven roller 6 are provided. The driven roller 6 and the stiffened roller 32 are made of a material with a low coefficient of friction such as polyacetal, and are configured to be able to rotate between them and a shaft 33 that is disposed through them. Both ends of the shaft 33 fit into notches formed in the frame B34, and the spring 35
The rollers are held by a driven roller 6 for sorting and a driving roller 9 for sorting. The frame B34 is provided with a support shaft 36 having the same axis as the support shaft 26 provided on the frame A22, and the support shaft 36 is rotatably supported by the main body frame 5. At the end of the arm 34a of the frame B34, a spring B is attached, similarly to the frame A22.
37 and a stopper pin 838 are provided to regulate the swing range of the driven roller 6 and to urge it to face in a certain direction.

Furthermore, a link 3 is attached to the arm 34a of the frame B34.
One end of the link 39 is rotatably attached by a pin 40, and the other end of the link 39 is attached to a plunger 41' of a solenoid 41 fixed to the main body frame 5.

Next, the operation of the sorting roller will be explained based on FIG. FIG. 4 is a diagram showing the sheet discharging operation seen from above. Hereinafter, the term "right side" or "left side" refers to the right side or left side in FIG. 4.

At the start, the image forming apparatus 1 is in an initial state in which no signal is sent out for sorting, so the solenoids 31 and 41 do not operate.Therefore, the springs A27 and B37 cause each sorting roller 6.9 to move as shown in FIG. It is oriented to the right as shown by the solid line. In this case, assuming that the operator is on the right side, the solenoids 31 and 41 are placed on the right side and the springs 27 and 28 are placed on the left side in order to make it easier to take out the ejection sheet. If so, you can swap the placement of the solenoid and spring on the left and right, or operate the solenoid from the initial state and sort using roller 6.
．． 9 may be directed to the left.

Furthermore, if the solenoids 31 and 41 that drive the drive roller 9 and the driven roller 6 are placed on opposite sides,
Since each solenoid operates alternately, the peak of the operating current value can be kept low, a small capacity power transformer can be used, and the device can be miniaturized. However, in this system, there is a risk that if the solenoid fails, it will not be possible to sort the ejected sheets or even to stack them on the left side.

In the above initial state, in this embodiment, the roller 6.9 is moved to the right by α degrees (8.5 degrees in this embodiment) If!
I'm there. In this state, the sheet A discharged from the image forming apparatus is bitten into the sorting roller 6.9, but the leading edge of the sheet remains perpendicular to the central axis 42 and is moved to the right in the α degree direction to the position indicated by sheet B. progress towards. When the ejected sheet reaches the position of sheet B, its right edge touches guide pin 1.
Contact 5. When the sheet is in contact with the guide pin 15, the sheet tip remains perpendicular to the central axis 42 and cannot move to the right at α degrees, so the guide pin 1
The discharge sheet at the position of sheet H rotates about 5. Then, when the sheet reaches a state where the sheet C is in the same direction as the α degree direction, the rotation is stopped and the sheet is discharged in the α degree direction. The sheet is then stored at the position indicated by sheet D on the tray 4.

By the way, in order for the ejected sheet to rotate from the state of sheet B to the state of sheet C, the sheet must slide at the nip of the roller 6.9 during sorting, but if it is easy to slip at the nip, for example, the conveyance guide 11. The sheet rotates due to the load caused by friction between the sheet 12 and the sheet, causing problems such as uneven stacking of discharged sheets on the tray 4.

The factors that cause the sheet to rotate include the width of the roller for sorting;
Although the material and nip pressure are different, we found the optimal conditions where the feed is stable, the roller rotates under load due to contact with the guide bin 15, and does not rotate under other loads, and the shape of the roller for sorting is as follows. It has been found that the shape shown in FIG. 5 is preferable.

First, since the driving roller 9 and the driven roller 6 are supported by separate frames, it is difficult to maintain constant line contact during operation, and the axes of both rollers may be misaligned, resulting in points. In this embodiment, in order to prevent this point contact from occurring, the diameter of the central portion of the drive roller 9 is set to be smaller than that of the outer portion. The rollers 6.9 are configured to be smaller than the diameter so that both rollers 6.9 are always in contact with each other at two points. Specifically, the width l of the drive roller 9 is 20~
700, outer contact width ρ with driven roller 6;

The diameter of the center part was made small to avoid contact with the 3~1O dragon, and the material was a rubber such as chloroprene rubber or ethylene propylene rubber with a hardness of 40~70@. The material of the driven roller 6 was polyacetal, and the total nip pressure was preferably 50 to 200 g.

Further, on the driven roller side, a tension roller 32 is provided in order to give a stiffness to the discharged sheets, but this tension roller 32 is arranged near both ends of the driven roller 6 for sorting, and It is formed by a roller with a slightly larger diameter. The shapes of the driven roller 6 and the waisted roller 32 form the sheet 53 in a wavy shape to prevent the sheet 53 from bending in the discharge direction due to its own weight, thereby stably discharging and stacking the sheet 53. It is effective for this purpose. Note that disposing this stiffened roller is a technique commonly used in a discharge device of an image forming apparatus.

In this embodiment, the diameter D2 of the buckled roller 32 is set 2 to 81 larger than the diameter D1 of the driven roller for sorting, and the buckled roller is set at a position of 1z-5 to 10 points from the end surface of the driven roller for sorting. It was optimal to arrange 32 end faces.

Now, after a series of sheets have been discharged to the right side of tray 4, that is, for example, after printing out some data,
When moving to print out the next data, etc., the solenoid 3 is activated by a signal from the image forming apparatus main body.
1.41 is energized, thereby causing plunger 31',
41' is sucked, and the frames A22 and B34 are rotated about the spindles 26 and 36, respectively, via the links 29.39, and the sorting rollers 6.9 move to the left by α degrees (this implementation In the example, 8.5"HIJ'l is set.

Since the rotation angle of each frame is regulated by the stopper pin A28 and the stopper pin 838, even if the frame is tilted to the left, the axis 21 of the sorting drive roller 9 and the axis 33 of the sorting driven roller 6 are held parallel. There is. The solenoid remains energized until the next printout is completed, that is, while the sheet is being ejected to the left. The mechanism for ejecting the sheet to the left side in this case is the same as that for ejecting the sheet to the right side.

When the discharge to the left side is finished and the next data is to be printed out, the power to each solenoid 31, 41 is cut off by a signal from an image forming device such as a printer, and the sorting is resumed by the springs A27 and B37. roller 6
．． 9 is tilted to the right. This series of discharges is called a job, and the operation of sorting the zips (in the present invention, the operation of sorting them left and right) is called job separation, and the device for this kind of sorting is generally called a zip separator.

The sheets sorted and discharged left and right on the tray 4 partially overlap each other on the central axis 42, so that each acts as a "bookmark" for the other. Therefore, jobs can be distinguished no matter how many times they are repeated, making it extremely convenient to organize output sheets after printing. In addition, in this example, the angle of the left and right distribution is set to 8.5', but the angle is not limited to this, and for sorting, the left and right distribution is set at an angle of 5'' to 45'. It can be set in the range of °.

Next, the structure of the tray will be explained. FIG. 6 is a perspective view showing the overall configuration of an embodiment of the tray, FIG. 7 is a partial cross-sectional view showing the inclination of the ridge line on the central axis, and FIG. 8 is a perspective view showing the tray shown in FIG. 6 in the direction of arrow A. FIG. 3 is an end view taken along the slope of the ridgeline.

As can be seen from these figures, in this embodiment, the shape of the tray 4 is such that the center part is raised in a chevron shape, and the ridges &14
3 is configured such that it is tilted upward along the discharge direction and its tip gradually becomes wider. The ridgeline 43 is inclined at θ, -20” to 40° from the horizontal plane, and the left and right bottoms are 44.45
has an inclination of θ2-5@~20'' with respect to the horizontal plane.Furthermore, sheet side edge guide members 48 with a chevron-shaped cross section are installed near the left and right side edges at an angle of θ3=0~100 with respect to the perpendicular. In addition, a cutout recess 49 is provided at the center of the tip of the bottom in the sheet ejection direction, making it easy to reach when taking out the sheets stacked on the tray 4. Sheets can be taken out all at once with one hand.A wall portion 50 is integrally formed on the sheet ejection port side of the tray 4, and a wall portion 50 is provided at the center of the wall portion 50 on the sheet ejection side cover 17. , a pair of convex portions 69 [No. 12-1
12-3)], the convex portion 69
A pair of recesses 51 into which can be fitted are formed. Furthermore, a pair of tray holders 18 for sorting and fixing to the main body 3 of the apparatus are integrally formed on the wall portion 50 and protrude toward the sheet discharge port side.

Further, horizontal surfaces 46,47 are formed at the left and right corners of the bottom surface 44,45 on the sheet discharge port side.

Next, the sheet discharging and stacking operations will be explained based on FIG. 9. During sorting, the sheets 53 discharged from the rollers 6.9 are discharged almost horizontally without bending or hanging due to the action of the slanted rollers, and come into contact with the tray 4 at a point on the ridge fi 43 of the tray 4.

After that, the sheets are sorted and discharged by the roller 6.9, and due to the force of the discharge speed v0, the leading edge of the sheet is 0.
reach the point. The sheet that has reached the zero point gradually falls because air is trapped between the sheet and the bottom of the tray 4, and then slides on the tray bottom surface 44.45 due to the inclination angle θ1 of the ridge line and the inclination θ2 of the bottom surface. , it comes into contact with the sheet side edge guide member 48 and the ridge 52 of the wall portion 50 and stops.

In this way, the ejected sheets are stacked one by one on the tray 4, but if one of the stacked sheets is misaligned by a large amount, or even if the misalignment amount is about one dragon, a considerable number of sheets may be stacked. If the numbers are misaligned, the user will be confused by the irregularities. Therefore, the stacked sheets are required to be neatly aligned without a deviation of about 1 fi.

In the tray configured as in this embodiment, the sheet discharge speed V, sorting is determined by the discharge angle θ4 of the roller 6°9, the inclination angle θ1 of the ridge line 43 of the tray 4, and the bottom surface 44.
．． 45 and the inclination θ2 are mutually related, and the sheet product s! It was found that this had an impact on the behavior.

As a result of the experiment, the sheet discharge speed v0 is 300 to 90.
At 0m/see, the inclination angle θ of the ridgeline is =20~40',
It was found that the bottom surface inclination angle θ2-5~20@ and the roller discharge angle θ4-0~15'' for sorting are good.However, depending on the sheet discharge speed of the image forming apparatus, sorting depends on the sheet discharge speed by the roller. Since V is fixed, other elements must be set accordingly.

The ejection speed of the page printer tested this time was 160
w/see, so when sorting the sheet discharge speed of the device was set to 550 m/see, the inclination angle θ1 of the ridge line
-29°, angle of inclination θ of the bottom surface! The best sheet stacking condition was obtained when the sheet was sorted at -10° and the roller discharge angle was 04 m 5 ''.

Next, we will further explain the relationship between each element that affects sheet stackability. First, if the sheet ejection speed V is too fast relative to the ridgeline inclination angle θ1, or if the ridgeline inclination angle θ1 is small relative to the sheet ejection speed v0, the sheet may jump out of the tray 4, or the sheet may By the time the rear end reaches the wall part 50, the rear end of the sheet has completely fallen onto the bottom surface of the tray or the lower layer sheet, and the sliding stops due to frictional resistance with the bottom surface or the lower layer sheet. This causes the problem that the machine stops at a certain point.

The most desirable embodiment is that the trailing edge of the sheet falls onto the bottom surface of the tray or the lower sheet until it reaches the wall 50, and the sliding movement is braked by the frictional resistance between the sheet and the bottom surface or the lower sheet. When the sheet reaches 50, the sheet hits the wall 50 with a considerably reduced sliding speed. On the other hand, if the sheet hits the wall portion 50 at a high speed, the sheet will be bounced back by the reaction, causing the sheets to be stacked unevenly. Therefore, the inclination angle θ1 of the ridgeline is larger than necessary.
It is also not good to set a large value. In particular, when the inclination angle θ1 of the ridgeline becomes large, the phenomenon of rebounding occurs, and
Since the sheet lacks rigidity in the thickness direction, it is prone to buckling.
This will worsen the loading condition.

The discharge angle θ of the sorting roller 6.9 is used to adjust the position of the point where the tray 4 and the sheet first come into contact, and is closely related to the inclination angle θ1 of the ridge line 43 of the tray. If the angle θ formed by m43 (which is determined by the inclination angle θ1 of the ridgeline 43 and the discharge angle θ4) is large, the discharged sheet may push out the sheet below it.

An appropriate inclination angle θ2 of the bottom surface is necessary to prevent the sorted sheets from shifting in the left-right direction. That is, when the ejected sheet falls onto the bottom surface, air is trapped between the sheet and the bottom surface.

Then, as the air escapes, the sheets gradually fall, but if the bottom of the tray is horizontal, the sheets will fall while swinging back and forth from side to side, just like falling leaves on a tree. The sheets will be uneven, so I'll change the left and right sides.

It is necessary to tilt the bottom of the tray back and forth and slide the sheets on the bottom to improve alignment.

The longitudinal inclination of the tray is determined by the inclination angle θ1 of the ridgeline, and the left and right inclination of the tray is determined by the inclination angle θ□ of the bottom surface. Since the portion of the ejected sheet beyond the contact point is already in contact with the tray, the left and right deflection is suppressed and the sheet falls, but not completely.

In this example, since a warp sheet (a sheet with fibers extending in the conveyance direction) is used, the stiffness in the thickness direction in the horizontal direction is even weaker than in the vertical direction, so the inclination angle θ2 of the bottom surface is If it is made too large, it will buckle and the loading condition will deteriorate. Therefore, the inclination angle θ2 of the base is the inclination angle θ1 of the ridgeline.
I can't get much.

Furthermore, if the inclination angle θ2 of the bottom surface is large, the sheet will not bend completely along the bottom surface 44°45 on the ridgeline 43, as shown in FIG. If the distance e to the top surface of the stacked sheets is large and the inclination angle θ of the bottom surface is small, the distance Me from the ridge line 43 to the top surface of the sheets can be similarly small, as shown in FIG. 1O-2. In addition, when the inclination angle θ□ of the bottom surface is large, as shown in FIG.
Since the tip of the stacking sheet 54 comes into contact with the tip of the stacking sheet 54, the stacking sheet 54 may be pushed out. In particular, the edges of the sheet have protruding fibers and are easily caught, making this phenomenon more likely.

For the above reasons, the inclination angle θ2 of the bottom surface cannot be large,
As mentioned above, 02-10° was the most preferable value.

When a sheet i sorting apparatus equipped with such a tray is used by connecting the apparatus to an image forming apparatus, for example, a medium-speed page printer, the number of sheets to be stored in the tray needs to be 500 or more. As the number of sheets stored in the tray increases, the position of the contact point between the leading edge of the ejected sheet and the ridgeline of the tray shown in Figure 9 changes, so depending on the distribution of the number of sheets to be sorted left and right, the number of sheets stored in the tray increases to 200. When the number of sheets exceeds 300, sheets already loaded may be pushed out, or the sheets may not slide down to the ridgeline 52 of the tray wall 50 and may stop midway due to the frictional resistance between the sheets. Therefore, as the number of sheets stacked on the tray increases, it is necessary to lower the tray.

It is conceivable to place the dead weight lowering mechanism for lowering the tray at the bottom of the tray, but the problem is that placing the mechanism at the bottom of the tray requires space and becomes an obstacle to miniaturizing the device. occurs.

In the embodiment of the present invention, in order to improve this point, the tray weight lowering mechanism and the sheet sorting mechanism are disposed at the lower part of the main body of the apparatus, thereby making the entire apparatus compact.

FIG. 11 is a perspective view showing such a tray weight lowering mechanism applied to the sorting apparatus according to the present invention. Note that in FIG. 11, illustration of the main body frame 5 and the sheet discharge side cover 17 is omitted. The tray 4 has its tray holding portion 18 inserted into an insertion hole provided in a tray holding member 19 disposed inside the main body frame 5, and is fixed with screws 58. On the left and right sides of the tray holding member 19,
Two guide rollers 59 are each rotatably attached to shafts 60. The guide roller 59 is connected to a guide hole 61 provided in the main body frame 5 (see Fig. 2).
It is configured to move up and down along the In addition, two guide rollers 62 are rotatably attached to the side surface of the tray holding member 19 opposite to the tray insertion side by means of a shaft 63, so as to move up and down along a guide hole 64 provided in the main body frame 5. It consists of The tray holding member 19 is urged toward the upper surface of the main body frame 5 by a spring 20 (see FIG. 2), and when the tray 4 is not loaded with sheets, each guide roller 59 and 62 are pushed into the guide hole. 61.64
It is stuck in the uppermost position.

When sheets are loaded onto the tray 4, the weight of the sheets stretches the spring 20, the guide rollers 59, 62 roll and move along the guide holes 61, 64, and the tray holding member 19 descends. Therefore, this tray holding member 1
The tray 4 supported by the tray 9 also descends according to the number of sheets loaded.

-a The sheets used in page printers are often high-quality paper with a weight of 60 to 120 g/r+f and a thickness of 70 to 120 μm. A4 size (210X297
mm) sheet, the unit weight should be 90g.
/rrr.

When the thickness is 95 μm, the spring constant of the spring 20 is k =
90g/cd x (0,21m xo, 297m
)X (110,00095m) =5900g/m=5.9 g/mwa. However, the weight of the sheet actually used is 60 to 120 g/
The spring constant does not necessarily have this value because it varies, but the tray lowers in approximately proportion to the sheet volume RIJk, and the ejected sheet and tray, or the sheets loaded on the tray. Contact point b (9th
(see figure) does not deviate significantly, a good loading condition can be obtained.

When the output sheets are not sorted, the sheets are stacked on the right side of the tray. Or, depending on the sorting method, a large number of sheets may be stacked on the left side. In those cases, the load applied to the tray becomes unbalanced from side to side, but since the tray holding member 19 is supported in the left and right direction by the guide rollers 62 and guide holes 64, the tray 4 will not tilt.
The descent is also smooth.

By the way, in order to stack the output sheets that have been sorted in the sorting device without shifting, the tray's sheet stacking bottom and the wall that supports the rear end of the sheets are integrally formed, and the tray is made elastic. In the case of a configuration in which the tray is supported and lowered by the weight of the sheet, the height of the tray wall portion 50 is determined mainly by the point of contact between the tray 4 and the discharged sheet, and the inclination of the ridge line 43. Therefore, in a case where the tray is constructed using only a tray having such a structure and a lowering mechanism, when the stacked sheet I becomes large and the tray is lowered, the rear end of the ejected sheet 72 is moved as shown in FIG. 15 mentioned above. The sorted items are stacked beyond the tray wall 70 and in contact with the wall 74 of the main body of the apparatus. In this case, the leading edge of the stacked sheet 72 is shifted by m from the leading edge of the sheets stacked in the tray, and furthermore, it suddenly shifts in the middle of the stacked sheets, so the sorting is not desirable from the aspect point of view. The drawbacks mentioned above also occur.

In order to solve this problem, in the present invention, as shown in the perspective view of FIG. 12-1, FIG. A pair of convex portions 69 are arranged on the sheet discharge side cover 17 so as to correspond to a pair of notch recesses 51 formed in the center of the wall portion 50 .

That is, the upper end position of this convex part 69 is set to be equal to the upper end position, that is, the height, of the wall part 50 of the tray 4 when there is no stacked sheet, and the convex part 69 is set to be equal to the upper end position, that is, the height, of the wall part 50 of the tray 4. The inner surface of the wall portion 50 and the surface of the convex portion 69 match, and the convex portion 69
The length of is set to be larger than the descent Ik of the tray 4.

The tray weight lowering mechanism is configured so that the lowering operation of the tray 4 is completed due to the weight of the sheets before the height of the stacked sheets exceeds the wall portion 50.

With this configuration, when the amount of loaded sheets increases and the operation of lowering the tray 4 by k ends, the ejected sheets are stacked beyond the wall 50 of the tray 4, but the wall The rear end of sheets loaded in excess of 50
It is supported by the central corner portion 69a of the surface of the convex portion 69. Since the surface of the convex portion 69 is arranged to match the surface of the wall portion 50, it is supported in line with the discharge sheet supported by the ridge 52 of the wall portion 50, and therefore the fifteenth The shift shown in the figure will no longer occur, and will not cause discomfort to the user.

Further, the rear end of the ejected sheet is supported by contacting the ridge 52 of the wall portion 50 that is lowered together with the tray during the lowering operation, and after the lowering is completed, the rear end of the ejected sheet is supported by the surface of the convex portion 69 provided on the sheet ejecting side cover 17. Since the rear end of the sheet is supported by abutting against the central corner 69a, the rear end of the sheet does not move relative to the member that abuts and supports the tray. The lowering operation is controlled only by the weight and is carried out smoothly, and the trailing edge of the sheet does not deform due to the lowering operation, making it possible to stack a large amount of sheets in an orderly manner.

In the embodiments shown in FIGS. 12-1 to 12-3 above, a protrusion that abuts and supports the rear end of the stacked sheets after the lowering operation of the tray is completed is separately provided on the sheet discharge side cover 17. However, as shown in the perspective view of Fig. 13-1 and the top view of the main part in Fig. 13-2, the contact support protrusion is integrated with the sheet discharge side cover 17. It can also be formed into

That is, the protrusion 69' may be formed integrally with the sheet discharge side cover 17 so as to have the same protruding surface shape as the protrusion 69. Further, the abutment support protrusion is not limited to a block-like one as in the above embodiment, but can also be composed of a strip-like protrusion, and similar effects can be achieved.

Unless the operator removes the sheets, the sheets stacked on the tray will continue to accumulate, and when they reach the ejection port, the sheets will be pushed out of the tray. It is necessary to detect that a predetermined number of sheets have been stacked on the printer and stop the operation of the image forming apparatus such as a page printer.

FIGS. 14-1 and 14-2 are diagrams showing an example of the configuration of means for detecting the amount of sheets loaded on the tray. The configuration example shown in FIG. 14-1 is configured such that the tray holding member 19 comes into contact with the actuator 66 in the lowered position, and the microswitch 65 is activated. That is, as the sheets are stacked on the tray 4, the weight of the sheets causes the tray 4 and the tray holding member 19 to be moved by the spring 2.
0, and when a predetermined number of sheets have been loaded, the lower end of the holding member 19 comes into contact with the actuator 66, and when more sheets are loaded, the microswitch 65 is activated and sends out a detection signal. This detection signal is sent to the CPU of the image forming apparatus main body.
The image forming apparatus is configured to control the operation of the image forming apparatus to stop after printing a predetermined number of sheets.

FIG. 14-2 shows the actuator 68 contacting and pressing the tray holding member 19 when the tray holding member 19 is in the raised position, that is, when no sheets are stored on the tray. The microswitches 67 are arranged as shown in FIG. In this configuration example, as the sheets are stacked on the tray 4, the tray 4 and the tray holding member 19 descend due to the weight of the sheets.
The actuator 68 moves and the microswitch 67
is activated and sends out a detection signal. The main body of the image forming apparatus starts counting the number of printed sheets in response to the detection signal from the microswitch 67, and when a predetermined number of sheets has been counted, the operation of the image forming apparatus is terminated. Although this configuration example uses a microsinch as the detection means, any sensor that can detect the movement of the tray holding member can be used.

[Effects of the Invention] As described above based on the embodiments, according to the present invention, when the tray is in a state where it can be lowered, the trailing edge of the discharge sheet is supported by the wall of the tray, and when the tray finishes lowering. The trailing edge of the sheet that is later loaded beyond the wall of the tray is supported by a protrusion provided on the main body of the device, so that
In either case, the rear end of the sheet and its support member do not move relative to each other, so the tray descends smoothly, controlled only by the weight of the loaded sheets, and the sheet deforms due to the descending movement. A large amount of sheets can be stacked in an orderly manner without causing any misalignment of the stacked sheets.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a state in which a sheet sorting apparatus according to the present invention is attached to an image forming apparatus, and FIG. 2 is an enlarged sectional view of the main body of an embodiment of the sheet sorting apparatus according to the present invention. FIG. 3 is an enlarged perspective view of a part of FIG. 2, FIG. 4 is an explanatory diagram showing the sorting operation of the sorting apparatus shown in FIG. 2, and FIG.
Sorting is a plan view of the roller, Figure 6 is a perspective view of the tray,
FIG. 7 is a partial cross-sectional view thereof, FIG. 8 is an end view thereof, FIG. 9 is an explanatory diagram showing sheet ejection and stacking operations in the tray, and FIGS. 10-1 and 1O-2 are trays. FIG. 11 is a perspective view showing the tray weight lowering mechanism, and FIG.
Figure 2-1 shows arrangement B of the tray and the protrusion for supporting the rear end of the sheet.
FIG. 12-2 is a top view of the main part, FIG. 12-3 is a sectional view of the main part, and FIG. 13-1 is a top view of the main part.
A perspective view showing a modification of the embodiment shown in Figure 2-1, No. 13
Figure-2 is a top view of the main parts, Figures 14-1 and 14-
FIG. 2 is a diagram showing an example of the structure of the tray stack amount detection means, and FIG. 15 is a diagram showing the sheet sorting system proposed by the present inventors, showing the stack of ejected sheets 1IIB when the tray is lowered in the apparatus. . In the figure, l is an image forming device, 2 is a sorting device, 3 is a sorting device main body, 4 is a tray, 5 is a main body frame, 17
is a sheet discharge side cover, 18 is a tray holding section, 19 is a tray holding member, 20 is a spring, 44.45 is a tray bottom surface,
50 is a wall portion, 51 is a notch recess, 52 is a ridge, 69 is a convex portion,
69' indicates an integral protrusion. Patent applicant Olympus Optical Industry Co., Ltd. Figure 2 Figure 4 Figure 5 Figure 6 Figure 11 Figure 13-1 Figure 13-2

Claims (1)

[Claims] a discharge sheet stacking tray integrally formed with a bottom surface that rises in the direction of discharge of sheets discharged from the sorting device main body, and a wall surface that abuts and supports the trailing edge of the discharge sheets;
tray elastic support means configured to gradually lower the tray according to the weight of the stacked sheets, and to complete the lowering operation before the height of the stacked sheets exceeds the height of the wall surface of the tray; and the stacked sheets in the tray. and a protrusion disposed on the apparatus main body so that the rear end edge of the sheet abuts the wall surface at the same support position when the height of the sheet becomes higher than the wall surface. .