JPS58197150A - Apparatus for stacking cut sheet - Google Patents

Abstract

PURPOSE:To prevent sheets from colliding with each other when they are stacked, by providing an end brush having radially extending bristles with an end roller for guiding cut sheets onto a receiving table. CONSTITUTION:The ends of the bristles of the end brush 16 will be displaced by X against the end roller 4, and there is a relationship between the circumferential speed VL of the roller and the circumferential speed VB of the brush 16 such that VB>=VL. When the sheet 1 is stacked, that is, when the tip 1a of the sheet enters a contact section (f) between the roller 19 and the table 5 and abuts on the stop rack 6 to be stopped, the sheet 2 is bent along a guide plate 28, while the bristles pass from a point 16a to a point 16b, and then reach a point 6c at very high speed. In this case, the speed of the tips of the bristles is far higher than the speed VB, and therefore the tailing end 2b of the sheet is rapidly dropped onto the sheet 2 on the table 5 positively with the tailing end 2b pinched between the bristles.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cut sheet stacking device that cuts each page of continuous printing paper printed by, for example, a line printer into cut sheets, and stacks the cut sheets on a tray.

With the advent of laser beam electrophotographic line printers, etc., the speed of line printers has improved significantly in recent years, and with this, there has been a demand for post-processing devices for printed paper to be integrated. In addition, from the perspective of saving labor, post-processing devices require automatic paper cutting, and it has become a problem to "stack cut and sorted materials at high speed and reliably."Moreover, the printing paper used There are various sizes and speeds, and it is necessary to stack all of them reliably. There are many problems.The required stacking speed is 1 per second.
The VC of 0 pieces has also been reached, and it is necessary to stack 1 piece in 0.1 seconds. FIGS. 1 and 2 show a glimpse of the conventional stack system.

FIGS. 3 to 8 show examples of technical problems when attempting to stack at the above-mentioned speed using the methods shown in FIGS. 1 and 2.

First, the stack operation according to the conventional method will be explained with reference to FIGS. 1 and 2.

Cut sheet 1! ti, feed roller 3
Then, the receivers are released from the end roller 4Vc, and are stacked at an oblique angle so that they slide one after another onto the table 5. A guide rack 8 is fixed above the stacked sheets 2 to prevent the sheets 1 from floating up. When the sheets 2 are gradually stacked up, the optical sensor 9 detects the length of the sheets 2, and the receiver moves the table 5 up and down by the lifting belt 1.
4 by the lifting motor 13 in the direction of the arrow.
The guide rack 8 is lowered and controlled so that the gap H between the guide rack 8 and the upper surface of the sheet 2 becomes approximately constant vC. The sheets 2 are regulated and aligned by a front rack 7 provided at the sheet discharge @ and a stop rack 6 provided at the counter discharge 01ll. The front rack 7 is fixed to the base 12,
The stop rack 6 attached to the Je moving rod 10 is indicated by the arrow LR.
By moving to , the front rack 7 and the stop rack 6 are made to face each other at a position If that matches the cut length t. 1
1 is a frame that includes the end roller 4 and the guide rack 8.
A sliding mechanism for the moving rod 10, etc. (not shown) is mounted.

When performing a high-speed stacking operation using the stacking method described above, problems as shown in FIGS. 6 to 8 occur.

(])/-Longitudinal misalignment (@Figure 3) Stop rack 6
The distance W between the front rack 7 and the front rack 7 is the sum of the paper cut length t and the gap Δt. After the seat 1 collides with the stop rack 6, it rebounds in the direction of the arrow and approaches the front rack Z, causing a phenomenon in which the end surface of the seat 2 is fairly aligned at Δ.

(2) Misalignment in the sheet width direction (FIG. 4) Due to the rebound, the sheet 2 moves downward across the width direction B, causing the sheet 2 to bend and become misaligned, causing the L phenomenon.

(3) Breaking of the tip of the sheet (Fig. 5) If the gap H between the guide rack 8 and the top surface of the sheet 2 is not an appropriate value, the tip of the sheet) 2 may bend and break. Optical. The range of H in which bending does not occur is very narrow, and sheet 2I: Control of surface flatness and gap H.
- Considering mold, it is difficult to maintain a constant range using this method.

(4) Rear-end collision of sheets (Fig. 6) A condition for high-speed stacking is to bring the preceding sheet 2 and the succeeding sort 1 as close as possible.
When the trailing edge does not complete its fall, a rear-end collision occurs when the leading edge of the trailing sheet 1 is released. The time interval between the leading edge and the trailing edge of the period is required to be 30+ns or less, and it is difficult to make it 30 ms or less using this method.

(5) Overtaking stack (Figure 7) Sheet 2 should be stacked, but the rear end of the preceding sheet 2 is partially affected by the inertia of sheet 2 and the static air of guide rack 8. Since it comes into contact with the 11 river part of guide rack 8, the fall is slow.
A phenomenon occurs in which the object enters the side.

(6) Unable to stack (Fig. 8) If the setting of the gap H is inappropriate and the stacking deflection of the sheet 2 increases, the upper ID of the sheet 2 will bend by one degree, causing local guide ν warpage 8. The gap between the sheet 2 and the upper surface of the sheet 2 becomes small, or the sheets 2 come into contact with each other, and the sheet 2 slips successfully or fails and cannot be stacked.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks of the prior art and provide a cut sheet stacking device that can stack cut sheets at high speed (continuously).

In the present invention, when the sheet slides into the tray, if there is a space on the top surface of the sheet, the light leakage of 1)-) may be bent or
- Since the sheets move and become misaligned, we focused on the fact that these problems can be solved by always applying a constant M load on the paper, so that even if the cut length of the sheet changes, the load is always applied. The holding plate and stack detection mechanism have been devised. Furthermore, in order to prevent the back end of the sheet from colliding with the front end, we focused on the fact that the brush has a high repulsion speed when the brush is released from the displaced state. High end.

It was devised to make the sheets fall at a high speed, stack them while giving the sheet itself VC deflection, and use the recovery power of this deflection to help the sheet fall quickly.

FIGS. 9 and 10 show the overall configuration of a stacking device according to the present invention. The configuration and operation will be explained below with reference to FIGS. 9 and 10.

The cut sheet 1 is fed by an end roller 3 from the direction of the arrow M, and an end roller 4 having a circumferential speed VL equal to the paper feeding speed by the feed roller 6 by y;
With the end brush 16 having a circumferential speed Va opposed to this, the receiver is slid onto the table 5 and stacked. The speed of the sheet 1 is required to be 50 inches/second to 100 inches/second. The stacking speed varies depending on the cut length t of the sheet 1, but reaches about 10 sheets/sheet to 6 sheets/second, and the time interval between the trailing edge of the preceding sheet 2 and the leading edge of the succeeding notebook 1 is 30 m8 or less. When the trailing edge of the preceding sheet 2 falls slowly, the leading edge of the trailing notebook 1 collides with it 1'i. The end plastic/16 is provided to reduce the road speed of the rear end of the seat 1, and its detailed operation is shown in Figures 23 and 24.
This will be explained later using figures.

Several strip-shaped presser plates 17 are placed on the upper surface of the sheet 2 so as to be in close contact with each other. ff1 of presser plate 17
Appropriate amount is 5 to 10 grams per irjt sheet, and the plate thickness is O,t.
It is preferable to purchase materials that reflect the true nature of MilJ. This temporary presser foot 17 has one end attached to a fixed $18 and the other end attached to a hanger bin 20.
It is supported by being hooked onto the sheet 2, and is devised so that it always acts on only one sheet 2, regardless of how many sheets 2 are stacked. The detailed structure of the presser foot IkL17 is shown in FIG. This will be described later using Figure jg22.

It is regulated by the stacked seats 2Fi, the front rack 7 including the base 12KLu, and the stop rack 6. The stop hook 6 is suspended from the movable rod 10, and the movable rod 1
0 position, L at the position corresponding to t1 cant length t on frame 11
8R million [iJ VC slide makes it look like a monkey. I to stop rack 6! The detection arm 22 is rotatably fitted into the LI rectangular arm pin 24, and the vL ratio is 7.
A roller pin 23 is fixed to a part of the detection roller 1? It is attached to the rotary b'' function. It is preferable that the detection arm 2 and the detection c-ra 19 be as wide as possible, so that they always rotate counterclockwise around the arm bin 24 due to the action of the center of gravity V.

Therefore, when there is a sheet 2, there is a light contact L on the sheet 2.
1. When the sheet 2 is removed, the upper end of the arm 22 comes to rest against the arm stopper 26 attached to the moving rod 10Vc. When the sheet 2 reaches the stack height and its top surface becomes high, it starts rotating in the direction of the arm 22rjJNi, and when it rotates at a certain angle, the non-contact switch 25 attached to the moving rod 10 is activated, the stack height of the sheet 2 is detected, and the receiving The platform 5 is connected to a lifting motor 13 via a lifting belt 14.
It descends by a certain amount in the direction of arrow p. The amount of descent per time is about 5 nn. Details of the height detection and platform lifting and lowering operations will be described later with reference to FIGS. 11 to 14.

If the cut length t of the sheet 2 is short, the moving rod 10'J
By moving in the direction of the arrow t, the stop rack 6, detection roller 19, non-contact switch 25, etc. can be moved to the position tM-.

Next, a specific example for solving the above technical problem will be described with reference to FIGS. 11 to 14. The technical problems addressed here are (1) misalignment in the sheet length direction, (2J
Misalignment in the talker direction, (5) sheet leading edge folding, (6) inability to stack. . The cause of problems (1) and (2) is that the A brilliant force that suppresses the movement is not acting on No. 12, and the problem (3) is that there is a space on the top of the sheet 2. Problem (6) is caused by the excessive frictional force.

In other words, the necessary conditions for solving these problems are as follows.

(b) Empty on the top of sheet 2! ' kl, apply an appropriate frictional force to the sheet 21 (b) The frictional force should not become excessive (/→ The frictional force remains constant even if the stack of sheet 2 changes) Sheet Even if the upper surface of 2 changes over time, the frictional force will change little (e) Even if the sheet-to-cut length t changes (a)
It has been experimentally confirmed that the above-mentioned requirements are satisfied by the examples shown in FIGS. 11 to 14 1'.

FIG. 11 shows state 7 at the start of the stack. On the stand 5, several rectangular holding plates 17 are mounted on the stand 5 so as to apply an appropriate force to the sheet 2 and to prevent the sheet 2 from collapsing. Just inside the stop rack 6
The detection roller 19 is repaired with a
9 has the purpose of giving mm sword to sheet 2. Detection roller 1? The configuration is as explained in FIGS. 9 and 10.

The non-contact switch 25ri is in the ON state by the detection arm 22.

The position t of the upper surface of the stand 5 of the receiver in this state is indicated by U. Continuing, when stacking starts -3i, /-toe 2 changes at high speed and the receiver passes between table 5 and presser foot 17, and the detection roller]
9 to 2) Zuka l? : Rotate and collide with stop rank B. When the weights of the presser 17 and the inspection roller 19 are at appropriate values, misalignment due to ID rollover does not occur in position sort 2. Also, the leading edge of the sheet 2 does not fold or the stacking phenomenon does not occur. It has been experimentally confirmed that even if the cut length t changes, the weight remains constant.Every time the sheets 2 are stacked, the first one to be detected floats up by the thickness of the sheet 2. The detection arm 22 rotates little by little in the ↑ direction.Since the detection roller 19 itself also rotates, the force exerted by the sheet 2 on the detection arm 22 is alleviated, and the operation of the detection arm 22 is stabilized. .

When the sheets 2 are stacked together, the presser plate 17 is also lifted in the U direction. In order to keep the frictional force between the presser plate 17 and the plate 2 constant, the presser plate 5 and 7 must always be free. That is, one end of the presser plate 17 must be rotatably supported around the fixed rod 18, and the other end must be freely supported so as to be movable in the left-right direction. This support structure is shown in FIG.

That is, in Figure @22, one end of the presser plate 17 is fixed to the rotating sleeve 27 fitted into the fixed rod 18 with a rotation 0T function, and the other end is provided with a square hole 17c, which is press-fitted into the hanger handle 21. It is designed to be hooked onto the 2DK square hole 17C. By doing this, the weight of the presser plate 17 can be applied to the upper surface of the sheet 2 in a constant manner.Also, since several presser plates 17 are installed in the form of strips, On the other hand, since each holding plate 17 acts independently, there is almost no change in the frictional force against the dog.

! [In Fig. 12, when the paper 2 is stacked by the height S, the detection arm 22 connects the non-contact switch 25 to the O'FF
Then, the receiver platform 5 descends a certain amount as shown in FIG. 16 and then stops. The upper surface of the seat 2 when stopped is approximately at the position Uf shown in FIG. 11.

As the platform 5 descends, the retaining plate 17 also descends in the D direction while touching the upper surface of the sheet 2, one end of which rotates clockwise, and the other layer moves to the left, keeping the friction force constant. It will be done. Simultaneously with the descent, the detection roller 19 also returns counterclockwise due to the movement of its center, and the non-contact switch 25 is turned ON again.

Next, stacking is started and the same operation is repeated.

FIG. 14 shows the operation when stacking is completed. When stacking is completed, the tray 5 is lowered to a position where the paper 2 can be taken out. At this time, the holding plate 17 is supported at both ends by the fixing rod 18 and the hanger bin 20, and is bent by its own weight. It is spaced apart from the top surface of the sheet 2 so as not to become an obstacle to taking out the sheet 2. On the other hand, the detection roller 19 is held while its rotation is restricted by the arm stopper 2B.

With the above configuration and operation, it is basically possible to stack cut sheets at high speed. However, when the cut at is extremely short, for example when using 6.0 inch paper, a problem arises in that a space is created between the presser plate 17 and the sheet 2. @Figure 15~! [Figure 17 KFi shows this problem and means for solving the problem.

The commonly used cut length is a maximum of 1 max = 14 inches and a minimum of Am1n#'iiO inches, with 0.5 inch increments often being used.

Figure 3!15 shows the cut lengths Lrnhx, jmin and the corresponding rack spacings Wmax, Wm1n. Further, θ is the entry angle of the sheet 1. There is an appropriate range for the entry angle θ so that the leading end of the sheet 1 can smoothly slide on the VC and the leading end does not float up.

-1 to 15 to 171 [4] As shown in Fig. 15 (at zmin, that is, when the stop rack 6 is set at the position indicated by the broken line, the presser plate 17 is still in contact with the sheet 2. friction force must be applied.

However, a problem arises in that it is difficult to bring the presser plate 17 into contact with the shell 2 due to the bending curve due to the rigidity of the presser plate 17, the mounting space, and the constant entry angle θ.

Figure 16 shows a comprehensive solution to this problem. The key point of this means is to utilize the detection roller 19. That is, in the state of Wm1n, the detection roller 19 is arranged so as to be at the position of the solid line riIt. Specifically, as shown in FIG. 17, the center of the detection roller 19 is placed at a position K with respect to the stop rack 6. It is preferable that K (FjL) be about 2 to 3 mm. When K becomes large, the leading edge of the sheet 1 entering the position will be at the position indicated by the broken line a shown in FIG. Sliding is obstructed. If K is too small, the height detection point becomes the end face of the sheet 2, and the detected height becomes unstable, and the frictional force will not act on the sheet 2 entering the sheet.
Misalignment occurs due to rebound 9.

In this way, in contrast to the optical sensor 9VC shown in FIG. 1, which has been used as a detection means in the conventional apparatus, the detection roller 19 according to the present invention is set at the position K shown in FIG. By providing the extension top and receiver near the contact point with the table 5, stable paper height detection can be obtained, and the effect of frictional force on the sheet 2, especially t.
A great effect can be obtained against the frictional force on the min paper, and the problem with the presser plate 17 can be solved.

At the 15th point, the distance at which the presser plate 17 acts is approximately -vman knee Wm1n. Paper cut length t is tsi
The closer to n, the shorter the above-mentioned acting distance becomes, and therefore the frictional force decreases, but the sheet cut length also decreases in proportion to this, so the inertia of the sheet also decreases, and the buckling strength in the longitudinal direction of the sheet still decreases. It has been confirmed through experiments that the frictional force decreases and the 4-hour rebound phenomenon or tip breakage phenomenon does not occur because of the increase in frictional force.

Next, since the presser plate 17 described so far has a rectangular shape, some inconvenience may occur when the width of the sheet 2 changes. This disadvantage and its solution will be explained with reference to FIGS. 18 to 21.

Iris 181i1i! 1 shows an example of the arrangement of the presser plate 17 with respect to the sheet 2. W, Fi@ indicates the width of the sheet. The sheet width used is Wb (
Wa > Wh), that is, the presser plate 1
In the case where the end surface of the sheet 2 almost coincides with the end surface of the sheet 2, the sheet 2 released from the direction of the arrow is slightly bent as shown in FIG. It turns out. In this state, when the platform 5 is lowered, the sheet 2 becomes caught on the holding plate 17, which causes the sheets 2 to be misaligned and the holding plate 17 to be deformed.

In order to prevent this inconvenience, FIG.
It has been established. As a result, even if the sheet 2 is slightly bent, the sheet 2 will not ride on the presser plate 17.

Layers Next, specific embodiments will be described in response to problems with the conventional apparatus (4) rear-end collision of paper and (5) overtaking start-up.

As already stated, the time interval between the trailing edge of the preceding sheet 2 and the leading edge of the succeeding sheet 1 is required to be 30 m5 or less. Conventionally, even in the case of m-weight, many methods have been proposed for dropping the rear end of the preceding sheet 2 onto the tray 5 at high speed, and a method using the end brush 161i shown in FIG. 26 is already known. However, in this case, L5 shown in FIG.
In addition, the falling speed of the rear end 2b by the method of pulling down the sheet rot 2b with the brush tip of the end brush 16 is highest when there is no slip between the rear end 2b and the brush.

Due to the inertia of the deer L and the sheet 2, the rear end 2b temporarily separates from the outer periphery of the brush and then comes into contact with the outer periphery of the brush again, so the falling speed becomes 1 -, and the time t can be reduced. I can't.

In other words, it is difficult to increase the speed.

FIG. 24 shows a specific embodiment that makes it possible to increase the speed. Although not shown in the figure, in general, the smaller the sheet cut length, the greater the number of sheets stacked per unit time. That is, the value of t in FIG. 26 becomes smaller. For example, if the cut length is 5.5 inches, the stacking speed is 10 sheets/second, and one sheet must be stacked in 0.1 seconds.

In order to obtain this high speed, a method shown in FIG. 24 is provided.

The key point of this method is to apply a displacement of X to the brush tip of the end brush 16 with respect to the end roller 4, and use the repulsion speed of the brush tip to increase the falling speed of the rear end 2b.
Sheet 2 by folding and curved guide plate 2B
The purpose is to shorten the falling time by giving a deflection to the sheet 2 and utilizing the release force of the deflection while preventing free flight. The end brush 160 diagram shows the movement of one brush and does not show the flocking density of the brush.

In the figure, the circumferential speed vL of the end roller 4 and the circumferential speed VariVB of the end brush 16 are expressed as V1. The guide plate 28 is fed along the edge 1aH of the sheet 1 and the outer periphery of the end roller 4, and has a radius r.
The detection roller 19 and the receiver are in contact with the stand 5 +
ffi f, collides with the stop rack 6, and comes to rest. At this time, the rear end 2b is in the position shown in the figure, and the seat 2
is in a curved state along the radius r. Then, when the displaced brush reaches 16a→16br, the bluff is released from the displaced state and reaches point 16c at high speed.

At this time, the continuous layer at the tip of the brush is much larger than Vl. After the sheet I42b is bitten between the brushes by the curved and released blade of the sheet 2 and reliably changes from Vc2b to 2C depending on the repulsion speed of the brushes.

After that, the brush moves the sheet 2 at the speed of VB to the plate 5.
It works to press upwards. Reference numeral 29 denotes a static eliminating blade that utilizes corona discharge to remove damp air from the guide plate 28, and prevents the sheet 2 from adhering to the guide plate 28.

According to this method, the trailing edge 2b of the sheet can be reliably dropped at the knitting speed, making it possible to reduce the distance between the leading edge 1a and the trailing edge 2b, that is, the time 1-14. Comparatively faster stacking can be achieved. In FIG. 24, the case of WXni n is shown as rA, but the operation is exactly the same as t in the case of Wmax.

However, the brush of the end brush 16 is made of a material with little permanent deformation (on the other hand, the brush diameter and length are appropriately selected and the brush diameter and length are appropriately selected to prevent Mll wear. It is preferable that the material has a certain property.

For example, if the outer diameter of the x-51 plan is j140 mm, jl O,1
You can use a brush made of millimeter nylon thread.

According to the present invention, cut sheets can be reliably stacked faster than f-.

[Brief explanation of the drawing]

FIG. 1 is a side view showing the general structure of the conventional device, FIG. 2 is a perspective view thereof, FIGS. 3 to 8 are explanatory diagrams showing the drawbacks of the conventional device, and FIG. Perspective view, 10th
11 to 14 are sectional views showing the operation according to the present invention; FIGS. 15 to 17 are sectional views showing the arrangement of components according to the present invention; FIGS. Figure '0 is an explanatory diagram showing a problem caused by a non-explosion example, Figure 21 is a plan view showing a solution to the problem, Figure 22 is a perspective view showing details of some components according to the present invention, and Figure 26 is a Figure 24 is an explanatory diagram of the production of all the problems of the conventional device, and the solution to it is shown in Figure 60.
6 is a stop rank, 10 is a transfer rod, 16rt end brush, 17ri paper presser temporary, 1d is a fixed rod, 19Vi detection roller, 20 is a pin, 21 is a hanger, 22Fi
Detection arm 3vi, roller pin 24, arm pin 26, arm stopper 27, rotary sleeve 27, guide plate 8. Agent Patent Attorney Toshiyuki Usuda, 'F, -□,'J 5〔-1d-1 1 year old 1 year old f (fJ 8 year old Off 1 figure

Claims (1)

[Scope of Claims] 1) A cut sheet stacking device in which cut sheets discharged from a pair of feed rollers are stacked on a table with a first receiver provided diagonally below the feed rollers, the feed rollers and the receiver An end brush T- is provided on the threshold between the base and the end roller and has a number of radially extending bluffs facing the end roller via the cut sheet,
A cut sheet stacking device characterized in that the rear end of the cut sheet is dropped at high speed by the repulsive force of the end brush. 2) The cut sheet stacking device according to claim 1, wherein the distance between the outer periphery of the end roller and the outer periphery of the central axis of the end brush is smaller than the length of each brush of the end brush. 3) A cut sheet stacking device in which the cut sheets discharged from a pair of feed rollers are stacked on a table with a receiver provided diagonally below the feed rollers, and the feed roller and the receiver are arranged between the table and the cut sheets. an end roller provided, an end brush provided facing the end roller via a cut 7-t, and having a large number of brushes extending radially; and a front rack provided at the cut sheet discharge. , provided on the opposite exit side, and provided with a next stop rack that can be slid in the length direction (cut no).
The support is normal to the top surface of the cut sheet on the stand and holds the top surface of the cut sheet, and is slidable along the length direction of the cut sheet, and its rotation center axis is disposed a predetermined distance from the stop rack. and a downwardly curved guide plate provided on a line connecting the point of contact between the roller and the upper surface of the cut sheet and the point of discharge of the cut sheet by the end brush. A cut sheet stacking device featuring: 4) Claim 3, characterized in that a line section member is provided above the cocoon weight guide plate to remove static electricity from the guide plate.
The cut sheet stacking device described in Section 1.