JPS58197148A - Apparatus for stacking cut sheet - Google Patents

Abstract

PURPOSE:To stack sheets continuously at high speed, by making a holding plate of a springy rectangle thin plate for holding cut sheets to be stacked on a table so that a constant and light load is applied on the sheets at all times. CONSTITUTION:A holding plate 17 is made of a spring thin plate about 0.1mm. in thickness, and preferably has a weight of about 5-10g. On end of the holding plate 17 is engaged with a fixed rod 18 and the other end is engaged with a hanger pin 20, and only the own weight of the holding plate 17 acts on the sheets 2 independently of the height of the stack. In this arrangement, as the sheets 2 are stacked, the holding plate 17 is also elevated, and when the height of the stack of the sheets 2 reaches a height S and the table 5 is lowered a certain distance through a detecting arm 22 and a switch 25, the holding plate 17 is also lowered with it in contact with the sheet 2, during which the friction is kept constant all the time.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cut sheet stacking device in which, for example, continuous printing paper printed by a line printer is negatively canted every time to produce cut sheets, and a cut sheet receiving device is stacked on a table. .

With the advent of line printers using the laser beam photography method, the speed of line printers has increased dramatically, and as a result, there has been a demand for higher speed devices for printing paper. In addition, from the viewpoint of labor saving, automatic cutting of the inner paper is required in the post-processing device, and it becomes a problem to quickly and reliably stack the cut sheets. In addition, the printing paper that can be used has various types of noise and speed, and it is necessary to stack all of these sheets reliably.

The stacking method of cut sheets has been widely used in the field of copiers and post-processing equipment, but there are many problems with commercial speed stacking. The required speed of 3 stacks reaches 10 sheets per second, and it is necessary to stack 1 sheet with 01 sand. FIGS. 1 and 2 show an example of a conventional stack system.

FIGS. 6 to 8 show an example of a technical problem when trying to stack the fast dust using the methods shown in FIGS. 1 and 2.

First, the stacking operation according to the conventional method will be explained with reference to FIGS.
They are stacked by sliding on top of each other one after another. A guide rack 8 is fixed above the stacked sheets 2 to prevent the sheets 1 from floating. Once the sheets 2 are piled up, the optical sensor 9 detects the edges of the sheets 2, and the tray 5 is lowered by a fixed amount in the direction of the arrow by the lifting motor 13 via the lifting belt 14, and the guide rack 8 and the sheets 2 The gap H with the top surface is controlled to be approximately constant. Sheet 2 is sheet release @VC
By moving the stop rack 6 attached to the movable rod 1o in the direction of the arrow L←R, it is regulated and fixed by the front rack 7 provided and the stop rack 6 provided on the exit side. The front rack 7 and the stop rack 6 are opposed to each other, and 11 is a frame on which the end rollers 4, the guide rack 8, a sliding mechanism for the movable rod 10 (not shown), etc. are mounted.

When performing related stacking operations using the stacking method described above, intermediate points as shown in FIGS. 3 to 8 occur.

(1) Misalignment in the sheet length direction (FIG. 6) 151 nW between the stop rack 6 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 bounces back in the direction of the arrow and approaches the front rank button 7, leaving the end surface of the seat 2 in an uneven row by 1 Δ.

(2) Misalignment in the straight direction of the sheets (Fig. 4) Due to the rebound, the sheet 2 moves in the straight direction B or F, and the sheet 2
A phenomenon occurs in which the parts are bent and misaligned.

(3) Bent end of sheet (Figure 5) Guide rack 8
If the gap H between the upper surface of the sheet 2 and the upper surface of the sheet 2 is not an appropriate value, the leading edge of the sheet 2 will be bent and folded, resulting in dust breakage.

The range of H in which folding does not occur is very narrow, and it is difficult to maintain a constant range in this method when considering the amount of control of the flat yoke on the upper surface of the sheet 2 and the gap H.

(4) Rear-end collision of sheets (Figure 86) A condition for high-speed stacking is to bring the preceding sheet 2 and the following sheet 1 as close as possible. Advance seat 2
When the trailing edge has not completed its fall, the leading edge of the trailing sheet 1 is released, causing a rear-end collision. The time interval between the front end and the rear end is required to be 30 mE3 or more, and it is difficult to make it 60 mE3 or more using this method.

(5) Overtaking stack (Figure 7) Sheets 2 should be stacked = rm v, but the rear end of the preceding sheet 2 is due to the inclination of the guide rack 8 due to the inertia of the sheet 2, the static electricity of the guide rack 8, etc. The falling of the seat is delayed due to contact with the seat, and a phenomenon occurs in which the succeeding seat 1 falls under the preceding seat 2.

(6) Unable to stack (Fig. 8) If the setting of the gap H is inappropriate and the amount of sheets 2 stacked increases, the upper surface of the sheet 2 will become uneven, causing the guide racks 8 and 7 to be partially stacked. The gap between the top surface of the sheet 2 and the top surface of the sheet 2 becomes small, or the gap between the sheets 2 and the top surface of the sheet 2 becomes small, and the t-side 9 of the sheet 2 is obstructed, making stacking impossible.

SUMMARY OF THE INVENTION An object of the present invention is to provide a cut sheet stacking apparatus capable of stacking cut sheets continuously at high speed without the drawbacks of the prior art described above.

In the present invention, when a sheet slides into the receiver VC, if there is a space above the sheet, the leading edge of the sheet may be bent or the sheet may move and become misaligned, so a constant light load is always applied to the paper. Focusing on the fact that these problems can be solved by this, the holding plate and stack height detection mechanism were devised so that the load always changes even if the cut length of the sheet changes. Furthermore, in order to prevent the rear end of the sheet from colliding with the front end, the brush is used, and when the brush is displaced and released from a good condition, the repulsion speed of the brush is high. The sheet was devised so that the edges would fall at high speed, and the sheet itself would be stacked while being deflected, and the recovery force of this deflection would also be utilized to assist in high-speed falling.

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 a feed roller 3 from the direction of the arrow, and an end roller 4 having a circumferential speed VL equal to the paper feeding speed by the feed roller 6.
The bridge is stacked so as to slide onto the table 5 by an end puller A6 having a circumferential speed vR opposed thereto. The speed of sheet 1 is 50 inches/second to 100 inches/second
An abstract is required. The stacking speed varies depending on the cut length t of the sheet 1, but reaches about 10 to 31 seconds, and the time interval between the trailing edge of the preceding sheet 2 and the leading edge of the succeeding sheet 1 is 6 seconds.
It will be less than 0m8. When the trailing edge of the preceding sheet 2 falls slowly, the leading edge of the trailing sheet 1 collides with it. The end brush 16 is provided to increase the falling speed of the rear end of the sheet 1, so its detailed operation will be described later with reference to FIGS. 923 and 24 ic.

On the InVC sheet 2, several strip-shaped presser plates 17 are placed so as to be in close contact with each other under their own weight. The appropriate weight of the presser plate 170 is 5 to 10 grams per plate, and the plate thickness is preferably about 0.1 mm and made of a material with high springiness. This presser plate 17
has one end attached to the fixed rod 18 and the other end attached to the hanger pin 20 ['5
It is designed so that only its own weight acts on the sheet 2 at all times, regardless of the amount of sheets 2 stacked. The detailed configuration of the holding plate 17 will be described later with reference to FIGS. 21 and 22.

It is regulated by the stacked seats 2Ii, the front rack 7 with the pace 12VC7 added, and the stop rack 6. The stop rack 6 is suspended by a movable rod 10vc, and the movable rod 10 moves on the frame 11 at a position V according to the cut length t.
It is now possible to spheroid in the cL-R direction. The detection arm 22 is rotatably fitted into the arm bin 241C fixed to the stop rack 6. The roller bin 26 is fixed to the end of the detection arm 22, and the detection roller 19 is rotatably attached. These detection arms 22,
The detection roller 19 is preferably as lightweight as possible, and is designed to always rotate counterclockwise around the arm pin 24 due to its center of gravity.

Therefore, when the sheet 2 is present, it lightly contacts the sheet 2, and when the sheet 2 is removed, the upper end of the arm 22 hits the arm stopper 26vc attached to the movable ring 10 and comes to rest. When the sheets 2 are stacked and the top surface becomes ^, the arm 22ri starts to rotate clockwise, and when the arm 22ri rotates at a certain angle, the non-contact switch 25 attached to the mover 1110 is activated, and the stack height of the sheets 2 is increased. Detected, the platform 5 is connected to the lifting motor 1 via the lifting belt 14.
6, it descends by a certain amount in the direction of the arrow. - The amount of descent per time is about 5 strokes. The relationship between height detection and the lifting and lowering operations will be described later with reference to FIGS. 11 to 14.

When the tight length t of the sheet 2 is short, the stop rack 6, the detection roller 19, the non-contact switch 25, etc. can be moved to the position indicated by the broken line by moving the moving rod 10 in the direction of the arrow.

Next, with reference to FIGS. 111 to 14, concrete implementation of the above-mentioned technical problems will be explained. The technical problems addressed here are (1) misalignment in the sheet length direction, (2
) Misalignment in the sheet width direction, (6) Folding of the leading edge of the sheet, (
6) Non-stackable. The causes of problems (1) and (2) are that no frictional force is acting on the sheet 2 to suppress its movement, and the cause of problem (3) is that there is a space on the upper surface of the sheet 2. Moreover, the cause of problem (6) is that the frictional force becomes excessive.

That is, the necessary conditions for solving these problems are as follows.

((a) Appropriate frictional force should be applied to the sheet 2 without leaving any space on the upper surface of the sheet 2. (b) The frictional force should not be excessive. (1) The frictional force should not be excessive even if the stack of the sheets 2 changes. (b) Even if the upper surface of the sheet 2 is curved, the frictional force does not change much (e) Even if the sheet ρ cut length t changes, conditions (a) to (c) are satisfied. It has been experimentally confirmed that the above-mentioned requirements are satisfied by the specific examples shown in FIGS. 11 to 14.

FIG. 11 shows the state at the start of the stack. Several rectangular pressing plates 17 are placed on the stand 5 so as to apply an appropriate frictional force to the sheet 2 and to eliminate any space, so that they are brought into close contact with each other by their own weight. A detection roller 19 is placed under its own weight slightly inside the stop rack 6, and the purpose of this detection roller 19 is to apply a frictional force to the sheet 2. The configuration of the detection roller 19 is as explained in FIG. 49 and FIG.

The detection arm 22 keeps the non-contact switch 25 in the ON state. The position lt of the upper surface of the stand 5 of the receiver in this state is indicated by UT. Subsequently, when stacking is started, the tray 2 passes between the tray 5 and the holding plate 17 at high speed, rotates the detection roller 19 slightly, and hits the stop rack 2. If the weight of the presser foot 17 and the detection roller 19 are appropriate, the sheet 2 will be uneven due to rebound.
does not occur. Further, the leading edge of the sheet 2 does not fold or the situation that stacking is not possible occurs. It has been experimentally confirmed that the weight jt may be kept constant while the sheet cut length t changes. When the sheets 2 are stacked, the detection roller 19F floats up by the thickness of the sheet 2, and the detection arm 22 rotates little by little in the direction of the hour hand. The impact force acting at 22Vc is alleviated, and the operation of the detection arm 22 is stable.

As the two sheets are stacked, 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 sheet 2 constant, the presser plate 17 must always be free. That is, one end of the press plate 17 is rotatably supported around the fixed rod 18, and the other end is movable in the left and right direction.
There is peace of mind in supporting Noh freely. This support structure is
I looked at Figure 2. That is, in FIG. 22, the presser plate 1
One end of 7 is fixed to the fixed rod 18 with a rotating sleeve 27Vc fitted with a rotational capacity of 0.5V, and the other end is fixed with a square hole 17C and press-fitted into the hanger 21.
It is designed to hang 70.

In this way, the weight i1 of the presser plate 17 can always be applied to the upper surface of the sheet 2 in a constant manner. In addition, the presser plate 17t
Since several strip-shaped VCs are installed, each holding plate 17 acts independently against the curve of the sheet 2.
There is almost no change in frictional force for curved bends.

Referring to Fig. 12, when h1 + m2 are stacked by the height, the detection arm 22 is connected to the non-contact switch 25 J.
kOF 11', the receiver platform 5 descends a certain amount and stops as shown in FIG. The top of the seat 2 when stopped is approximately at the UT position shown in FIG.

As the platform 5 descends, the support plate 17 also moves in the D direction, and the sheet 2
It descends while touching the top surface, one end rotates clockwise, and the other end moves 1ζ to the left, keeping the frictional force constant. Simultaneously with the descent, the detection roller 19 also moves counterclockwise due to the movement of its center of gravity.
It becomes N. Subsequently, a stack is started and the same operation is repeated. Figure 14 shows the operation when stacking is completed. When stacking is completed, the tray 5 is lowered to the position where all sheets 2 can be taken out. At this time,
The holding plate 17 is supported at both ends by a fixed rod 18 and/or a hinge 20, and is deflected by its own weight. Further, it is spaced apart from the upper surface of the sheet 2 so as not to become an obstacle to taking out the sheet 2. - Force is applied to the detection roller 19 and the arm stopper 26 to restrict rotation and hold it as it is.

With the above configuration and operation, it is basically possible to quickly stack Erica sheets. However, when the force 7 and the length t are extremely short, for example when using 3.0 inch paper, a problem arises in that a space is created between the presser plate 17 and the sheet. FIGS. 15 to 17 show these problems and means for solving them.

The commonly used cut length is maximum jmax = 14 inches, minimum 7m1n is 3.0 inches, during which time 0.
The 15th picture size, which is often used in 5-inch increments, is force, length J2max,! ','-min and the corresponding rack spacing Wmax Wm1n Enter the approved values. It is also a 17i seat 1's corner castle. There is an appropriate range of 1γ for the entry angle θ in which the tip of the rotary hook sheet 1 can maintain a constant solar slippage and the tip does not float up.
Even at the time of Itmin, that is, when the stop rack 6 is set at the break-resistant position, it is necessary to apply a frictional force to the holding plate 17Fi sheet 2. However, due to the bending curve due to the rigidity of the presser plate 17, the space for mounting, and the reason that the two missing angles V at the front are constant, the presser plate 17
The main problem is that it is difficult to bring the button into contact with the sheet 2.

FIG. 16 VC shows a solution to this problem. The key point of this means is to utilize the detection roller 19. That is, state 7I of Wm1H! At IVc, the protruding roller 19 is arranged so as to be at the position # of the solid line. Specifically, as shown in FIG. 17V, the center of the detection roller 19 is placed at a position K with respect to the stop rack 6. K (7) Il+I ri of about 2 to 6 mm is preferred.

When K gets bigger! The position is indicated by the broken line a in Figure 16,
The leading edge of the sheet 1 entering the sheet receives resistance from the detection roller 19 [j], and the receiver is prevented from sliding onto the table 5. If K is too small, the detection point becomes the end face of the sheet 2, making the detection unstable, and at the same time, no frictional force is applied to the sheet 2 entering the sheet 2, causing misalignment due to rebound.

In this way, with respect to the optical sensor 9 shown in FIG. 1, which is used as a height detection means in the conventional device, the detection roller 19 by this @- is set at the position K shown in FIG. By providing the receiver on the extension line of the angle 0 and near the point of contact with the table 5, stable paper height detection can be obtained. (The problem with the presser plate 170 is solved because it has a large effect on the frictional force acting at the position of m).

In FIG. 15, the distance over which the presser plate 170 acts is approximately -
tWmax-Wn+in. Paper cut Lct
As ftm1nIC gets closer, the above-mentioned acting distance becomes shorter and the If force decreases, but the sheet cut length is proportionally shortened and the inertia of the sheet decreases due to the yaw. Because the stiffness is higher,
It has been confirmed through experiments that even if the Ia friction force is reduced, the rebound phenomenon and the pre-spill breakage phenomenon do not occur.

Next, since the presser plate 17d described so far has a rectangular shape, some inconveniences may occur in the VC when the width of the sheet 2 changes. This missing point and its resolution #! j, will be explained with reference to FIGS. 18 to 121.

Figure 18 shows arrangement 1+ of presser plate 17 with 2V
Use the one shown in 111. wH indicates 1 positive gold of a certain sheet. The sheet width used is wk as shown in Figure 19.
(W) When l > W=l +, that is, when the end face of the presser plate 17 and the end face of the sheet 2 almost coincide, the top seal is set as shown in FIG. The sheet 2 discharged from the direction is slightly bent and the sheet end surface 2a rides on the holding plate 17 & C. When the tray 5 descends, the sheet 2 becomes caught on the holding plate 17. Sheet 2 may be misaligned, presser foot 1#
, 17. In order to prevent this inconvenience, the #Ii[T[inner arrangement 7ax of the presser plate 17 is
17b is provided. As a result, C)2
This prevents the sheet 2 from riding up on the book and the holding plate 17 due to slight bending.

Next, a specific example will be described regarding problems with the conventional apparatus (4) rear-end collision of sheets and (5) overtaking stack.

It has already been stated in the nine cases that 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 3 Hmg or less. Even in the conventional device, the rear end of the optical sheet 2''
& The receiver is dropped onto the platform 5 at high speed [many methods have been proposed to drop it,
A method using an end brush 16 shown in FIG. 23 is also already known. However, in this case, as shown in Figure IE23, the tip of the plan of the end brush 16 is 7-tk;?
The falling speed of the rear end 2b using the method of dragging iA 2 b is y,! The height is reached when there is no slip between 2b and the brush.

However, due to the inertia of the sheet 2, it is temporarily separated from the outer periphery of the rear 42bd brush and then comes into contact with the outer periphery of the brush again, so the ffr'F speed becomes unstable and the time t cannot be reduced. . In other words, it is difficult to increase the speed.

FIG. 24 shows a specific embodiment for increasing the speed to 5T. Although not shown in the figure, in general, the smaller the sheet cut length, the greater the number of stacked sheets per standard time. That is, # of t in FIG. 26 becomes small. For example, for sheets with a cut length of 6.5 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.

1:・'・ 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 F speed of the rear end 2b. Sheet 2 by raising and curved guide plate 28
The aim is to shorten the falling time by giving deflection to the shell 2 and utilizing the release force of the deflection while preventing the free flight of the shell. The diagram of the end brush 16 shows the movement of 7971 hairs, and does not show the entire bristle density of the end brush.

In the figure, the peripheral speed VL of the end roller 4 and the peripheral speed Va of the end brush 16 have a relationship of VB≧VL, and the difference in peripheral speed is very small. The tip end 1ari of the sheet 1 is fed along the outer periphery VCa of the end roller 4, and while contacting the guide plate 28 having a half %r, the detection roller 19 and the receiver move to the contact portion fV with the table 5.
c) and 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. Continuing, when the displaced brush reaches 16a→16b, it is released from the displaced state □ 1'・1 and reaches point 16c at speed ^. At this time, the speed t of the tip of the brush is much larger than VB 1, and after the sheet ′;42b bites between the brushes due to the force released from the curvature of the sheet 2, and is reliably 2b→ due to the repulsion speed of the brush. Fall to 2c. Thereafter, the brush acts to press the tray onto the table 5 at a speed of 2fVa. 29
1 is a clearing rod that uses corona discharge to remove static abrasive air from the guide plate 28, and prevents the sheet 2 from adhering to the guide plate 28.

If this method [j is used, the rear end 2b of the sheet is reliably Kfl at high speed.
, because you can put it down! It becomes possible to reduce the distance between 111 and the rear end 2b, that is, the time interval,
Achieves faster stacking than conventional equipment. Same, 24th
In the figure, the case of Wm1n is cited, but the operation is exactly the same in the case of WmaX.

In addition, the brush of the end brush 16 is made of a material that has little permanent deformation with respect to the displacement It is preferable to have one.

For example, if x = 51 and brush outer diameter l1140 mm, I! 10.
A brush with 1mm nylon thread can be used.

According to Fusatsu iq, cut sheets can be stacked more quickly [and more reliably].

[Brief explanation of the drawing]

Fig. 1 is a side view showing the general configuration of a conventional device, Fig. 2 is a perspective view thereof, Figs. 3 to 8 are explanatory diagrams showing drawbacks of the conventional device, and Fig. 9 is a perspective view of a device according to the present invention. , 1st
FIG. 0 is a sectional view thereof, FIGS. 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 study, and FIGS. 18 to 20. 21 is a plan view showing a solution to the problem, FIG. 22 is a perspective view showing details of some components according to the present invention, and FIG. 26 is a conventional one. FIG. 24 is an explanatory view of the operation showing the problem of the device, and is a sectional view showing a solution to the problem. In the figure, 6 is a stop rack, 10 is a moving bar, 16Fi
End brush, 17 is paper press plate, 1B is fixing rod, 19
is a detection roller, 20 is a hanger pin, 21 is a hanger blade, 2
2 is a detection arm, 26 is a roller pin, 24 is an arm pin, 26ti arm stopper, 27ii rotation sleeve, 2
8 is a guide board, Patent Attorney Usui 1) Toshiyuki'1"sa・?1°i'ji' Sai 5 Leap Off Mountain Sai 1! Mouth Oqen Off 3 m Off 60 Ot7q Sai/80 Oroqro 21st

Claims (1)

[Claims] 1) A cut sheet stacking device in which cut sheets discharged from a pair of feed rollers are stacked on a table by a receiver provided diagonally in the direction F, the receiver being arranged on a table. A cut sheet stacking device characterized by being provided with a pressing plate made of a strip-shaped thin plate having spring properties that is always in close contact with the upper surface of the upper cut sheet and extends along the length direction of the cut sheet. 2) The cut according to claim 1, in which the cut 7 of the holding plate is rotatably supported, and the non-release 1g1l end is movably supported. Sheet stacking equipment. 6) The cut sheet stacking device according to claim 1, wherein the width of the presser plate is tapered so as to become narrower toward the opposite end.