JPS62215429A - Paper feed device for printer - Google Patents

Abstract

PURPOSE:To enhance the serviceability of a printer having a trial print mode, by elevating a paper feed bed with the use of an elevating means when the completion of trial print is detected, to rapidly and simply complete the preparation of printing. CONSTITUTION:In a rotary duplicator, printing sheets 25 stacked on a paper feed bed 25 are fed out one by one in association with the rotation of a paper feed roller 26 which makes into contact with the topmost one of the stacked sheets 24 during rotation of a printing barrel around which a porous original 16 is set, and are discharged into a discharge tray 32 after completion of printing. In this arrangement, if a trial print mode is set, when a trial print mode completion detecting circuit (which is not shown) detects the completion of the trial print, an elevating means including a rack 34 and a pinion 36 lowers the paper feed bed 25 by a predetermined amount. Therefore, a slight gap may be obtained between the paper feed roller 26 and the topmost one of the stacked sheets 24, thereby it is possible to adjust the movement of the sheets 24.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention relates to a paper feeding device for a printing press having a so-called trial printing operation mode, and in particular, the paper feeding tray automatically lowers after the trial printing operation is completed. It is characterized by this.

(B) Prior Art In conventionally known printing machines, the paper feed tray does not automatically lower even after the trial printing operation is completed.

Note that a copying machine has already been proposed in which the paper feed table automatically lowers when a jam (paper jam) occurs, making it easier to clear the jam (see Japanese Patent Publication No. 46709/1983).
.

The invention described in the above publication is ``a lifting device that lifts and lowers the transfer paper in a paper feed tray or a cassette, and a jam display that displays a jam indication when a jam occurs, stops the copying function, and drives the lifting device to automatically stop the copying paper from being in use. The transfer paper in the paper feed tray or cassette is lowered to a position away from the paper feed roller, and when the jammed paper is removed and the jam indicator is set, the lifting device is driven to raise the transfer paper so that the top of the paper is 1. A copying machine that facilitates jam handling, characterized in that it is equipped with a control device that raises the paper to a position where it contacts a paper feed roller and then makes it ready for copying.

Therefore, the paper feed tray lowers when a jam occurs, but it does not lower during test printing (because it is a copying machine, there is no test printing operation mode other than the normal operation mode).

(c) Problems to be Solved by the Invention As mentioned above, in conventionally well-known printing machines, the paper feed table does not automatically descend even after the trial printing operation, and the topmost printing paper is The paper remains pressed against the paper feed roller by the paper base.

Therefore, the printing paper may not be placed at the specified position on the paper feed table, and the printing position may be shifted (to the right or left in the paper feeding direction), causing a skewing phenomenon. In this case, it was necessary to manually lower the paper feed tray, separate the printing paper from the paper feed roller, and then rearrange and reposition the printing paper.

By the way, it is difficult to accurately place a large amount of laminated paper on the paper feed tray at once, and it is necessary to perform the above operation every time a new printing paper is placed on the paper feed tray. With this technique, the paper feed tray had to be lowered manually every time a trial printing operation was completed, which was very troublesome.

Note that the copying speed (printing speed) of a copying machine is slower than that of a printing machine, so there is no trial printing operation mode.
Problems like the ones mentioned above rarely occur.

B) Means for Solving the Problems The present invention provides a paper feed tray on which stacked printing sheets are placed, a lifting means for raising and lowering the paper feed tray, and at least when feeding the paper, the printing paper on the top A feeding roller for a printing press, characterized in that it is equipped with a paper feeding roller that comes into contact with the paper, and a control means that operates the elevating means to lower the paper feeding table when the end of the trial printing operation is detected. It is a paper device.

(E) Function In the present invention, when the trial printing operation is completed, the elevating means is automatically operated and the paper feed tray is lowered, so that the pressing force of the uppermost printing paper against the paper feed roller is reduced or canceled. be done.

Therefore, after the trial printing operation is completed, the operator can immediately adjust the printing paper on the paper feed tray.

(F) Embodiment FIGS. 1 and 2 are schematic configuration diagrams showing different aspects of a rotary copying machine equipped with an embodiment of the present invention. First, the overall configuration of the rotary copying machine will be explained with reference to these drawings, and then a specific explanation of the paper feeding device will be given.

(1) is the main body of a rotary copying machine, and a well-known cylindrical plate cylinder (2) is rotatably mounted inside. Said plate cylinder (2)
A support shaft (4) extending parallel to the rotation axis (3) is rotatably inserted near the peripheral side of the plate cylinder (2). A plurality of hook-shaped section hooks (5) that can protrude from the circumferential surface in the centrifugal direction are arranged along the extending direction. In addition, the support shaft (4
), a cam follower holding arm (6) is fixed to the protrusion from the side end surface of the plate cylinder (2), and a cam follower (7) is rotatably mounted near the free end of this arm (6). has been done. Therefore, the cent hook (5) and the cam follower (7) are configured to be able to swing together about the support shaft (4). Although not shown, the set hook (5) is fitted with a spring so that its free end is biased toward the center of the plate cylinder (2) (perpendicular to the rotation axis (3)). energized.

The cam follower (
The parts corresponding to 7) include a plate feeding cam (8) and a plate discharging cam (8).
9) are attached to a holding shaft OQαη implanted in the chassis (not shown) of the main body (1) so as to be able to swing slightly, and both cams (8) and (9) are U-shaped. They are connected by one link α. Further, a solenoid α→ is connected to the plate discharge cam (9) via a plunger α3. The edge of the plate feeding cam (8) facing the plate feeding section is connected to the plate cylinder (2).
) at the longest distance from the center of the plate discharge cam (9),
The edge facing the plate discharge section is also at the longest distance from the center of the plate cylinder (2). 00 is a tension spring provided on the opposite side of the link α, sandwiching the center of the plate cylinder (2), and biases both the cams (8) and (9) inward.

When the solenoid α4) is excited and operates as a suction, both the cams (8) and (9) are separated against the tension spring α, and move from the two-dot chain line position to the solid line position in FIG. do. That is, the plate feeding cam (8) moves from the non-plate feeding position to the plate feeding position, and the plate discharging cam (9) moves from the non-plate discharging position to the plate discharging position.

Therefore, when the cam follower (7) reaches the plate feeding section while the solenoid (14) is in suction operation,
This cam follower (7) comes into contact with the plate feeding cam (8), and the set hook (5) is biased to protrude from the circumferential surface of the plate cylinder (2) in the centrifugal direction. Furthermore, when the cam follower (7) reaches the plate discharge section, as shown in FIG.
In this case as well, the set hook (5) is biased to protrude in the centrifugal direction from the circumferential surface of the plate cylinder (2) by the plate discharge cam (9).

In addition, in this embodiment, the cam follower (7) is connected to the plate cylinder (2).
), this cam follower (7) is located upstream of the support shaft (4) along the rotation direction of the plate feeding cam (8).
When it comes into contact with the plate discharge cam (9), the set 7 nozzle (5) rotates clockwise about the support shaft (4) as a fulcrum, and its free end protrudes downstream.

The plate feeding section is provided with a guide 0η for inserting the stencil paper (16a) after making the plate toward the f plate cylinder (2).

In addition, the stencil paper (16b
) is provided with a base paper storage box in which a plate discharge part 09 is fixedly installed for peeling off the plate from the plate cylinder (2), and the plate discharge part Q
'The stencil paper (1) peeled off from the plate cylinder (2) is attached to the base of
6b) into the base paper storage box (1), a pair of meshing gears 12p (a) are provided. Note that this paper storage box is attached to the main body (1) so that it can be inserted into and removed from the main body (1) in the direction of the arrow. (To) is the gear 31) (A)
This is the driving gear that drives the.

A paper feeding device for feeding printing paper (to) is provided below the base paper storage box (a). This paper feed device mainly consists of a paper feed tray (C) on which a large amount of printing paper (C) is loaded and is movable up and down, and a paper feed tray (C) that is movable up and down.
and a primary paper feed roller (A) located above the downstream end of the paper and pressed against the uppermost paper (C). Details of the paper feeding device will be described further later.

On the downstream side of the primary paper feeding roller (E), there is a printing paper eI that has been fed by the primary paper feeding roller (C).
A pair of secondary paper feed rollers @(g) is provided for feeding the paper again at a timely manner after the paper has been temporarily stopped. @ (to) is a pair of paper feed guides.

A press roller 01) is pressed against the lower end of the plate cylinder (2) for printing by pressing the printing paper (C) against the stencil paper (16a). (2) is a paper discharge tray that stores and stores the printed paper (2) after printing.

When feeding the plate, the downstream end of the stencil paper (16a) after plate making is inserted between the guides αη (to) of the plate feeding unit, and then the plate feeding operation is started. Solenoid α4) is excited and operates to suck. Then, the plate feeding cam (8) moves from the plate non-feeding position to the plate feeding position, so when the plate cylinder (2) rotates clockwise (in the direction of the arrow) in this state, the cam follower (7) moves to the plate feeding cam. (8) and the set hook (5) stands up (1st M-Song phase station)
- When the cylinder (9) is inserted into the stencil (9), the set hook (5) engages with the engagement hole (not shown) of the stencil paper (16a), and the stencil paper (16a) ) are sequentially wound around the plate cylinder (2) from the downstream side.

The solenoid 0→ is controlled to stop the suction operation before the set hook (5) reaches the master discharge position, that is, before the cam follower (7) comes into contact with the master discharge cam (9). When the set hook (5) reaches the master discharge position, the master discharge cam (9) is moved to the non-discharge position by the spring aυ. Therefore, the cam follower (
7) does not come into contact with the plate discharge cam (9) and the set hook (5)
) does not protrude from the plate cylinder (2), so no plate ejecting operation is performed.

The plates are fed in this way and a predetermined number of printing sheets (C) are printed, but at this time, the plate feeding cam (8) is at the non-plate feeding position, and the plate discharging cam (9) is at the non-plate discharging position. In this case, the cam follower (7) is configured so as not to come into contact with the cams (8) and (9).

When printing is finished and the plate is ejected, the cam follower (7)
) is moving between the plate feeding cam (8) and the plate discharging cam (9), the solenoid 0→ is excited again and operates as a suction, and the plate discharging cam (9) moves from the non-plate discharging position to the plate discharging position in the same manner as described above. Move to. Then, the cam follower (7) comes into contact with the discharge cam (9), and the center hook (5) stands up while engaging with the stencil paper (16a) while lifting its end (see FIG. 2). When the plate cylinder (2) further rotates in this state, the downstream end of the stencil paper (16a) (the end lifted by the set hook (5)) is moved into the discharge mold 0.
It is peeled off and guided to the gear 121) (a). The stencil paper (16b) detached from the set hook (5) and guided is stored in the stencil storage box by the gear C2υ(a).

Next, details of the paper feeding device, which is a main part of the present invention, will be explained with reference to FIGS. 1 to 3. FIG. 3 is a partially enlarged front view showing the specific structure of the primary paper feed roller (c). The paper feed tray (c) is slidably held by a guide (to) vertically provided on the main body (1). Also,
A rack (B) is fixedly attached to the paper feed tray (C), and this rank (B) is connected to the paper feed tray drive motor (To) provided in the main body (1) via a reduction gear. It meshes with the pinion (to) connected to the pinion. Therefore, when the pinion (G) rotates in the forward and reverse directions, the paper feed table (C) moves up and down.

The primary paper feed roller (A) is mounted near the free end of a roller holding arm (7) that is swingably attached to a holding member (B) that is fixed inside the main body (1). It is configured to be rotatably mounted and to be applied with rotational force by means not shown. Further, an L-shaped actuator arm is fixedly attached to the roller holding arm (C), and the paper feed tray (C) is raised to feed the topmost printing paper (C) to the first printing tray. When it comes into contact with the lower part of the paper feed roller (1) and the roller holding arm (to) rotates clockwise around the spindle), the actuator (g) is attached to the holding member 01). The microswitch 01) is configured to fully operate and stop the rotation of the paper feed tray drive motor (to). Note that the roller holding arm end is slightly biased counterclockwise by a spring (not shown).

A separating plate (6) and a spring are pressed against the lower part of the primary paper feed roller holder to prevent double feeding of the printing paper (c).

Next, the control circuit of the paper feeding device will be explained mainly with reference to FIG. 4 (block diagram). In this figure, ■ is CP
U (central processing unit), (c) a memo 'J (ROM) in which the operating time of the paper feed table driving motor (to) in each operation mode, etc. are stored, and (g) an interface. 0η is the drive circuit for the paper feed tray drive motor (to), 2) is the circuit that detects the end of the trial printing operation, θ1 is the recording paper jam (paper jam) detection circuit, and (7) is the paper feed tray ( This is a circuit that detects the presence or absence of the recording paper (c) on the recording paper (c).

In this embodiment, the printing paper (c) on the paper feed table (c) is consumed when a jam is detected or the trial printing operation is completed, or even if the predetermined number of sheets has not been printed yet. When this happens, a detection signal is output from each of the detection circuits (c)0 (7), and in response to each of these detection signals, the paper feed tray drive motor (to) rotates for a predetermined time.

Therefore, each of the paper feed trays (c) is lowered by a predetermined distance.

Next, the operation of this embodiment will be explained based on FIGS. 4 and 5 (flowcharts).

In the paper feed tray lowering routine, it is determined whether or not a jam has occurred, and if it is determined that a jam has occurred, a timer (built into the CPU) is set to 2 seconds; The paper feed tray driving motor (to) starts operating. Then, when the timer is decremented to 0, that is, when the paper feed table (a) descends for 2 seconds, it stops.

Therefore, between the primary paper feed roller (1) and the uppermost printing paper (c), the printing paper (c) that caused the jam
A space is created in which the material can be removed.

On the other hand, if no jam has occurred, it is determined whether the trial printing operation has ended or not, and if it is determined that the trial printing operation has not ended yet, the timer is set to 0.5.
seconds, and at the same time the paper feed tray drive motor (to)
starts working. Then, when the timer is decremented and reaches O, that is, when the paper feed table (c) descends for 0.5 seconds, it stops.

Then, a slight gap is created between the primary paper feed roller (a) and the topmost printing paper (2). Therefore, it becomes possible to adjust the movement of the printing paper (to) on the paper feed tray (to).

Further, when the trial printing operation mode has already been completed and the printing paper (C) on the paper feed table (C) is positioned at a predetermined location, it is determined whether printing of a predetermined number of sheets has been completed; If it is determined that all the printing paper (C) on the paper feed tray (C) has been fed (consumed) even though the predetermined number of sheets have not been printed, the timer will start for 3 seconds. is set, and at the same time, the paper feed tray drive motor (to) starts operating. Then, when the timer is decremented and reaches O, that is, when the paper feed tray (c) descends for 3 seconds and reaches near the bottom of the main body (1), it stops.

Then, a space is formed on the paper feed tray (c) in which the required number of printing sheets (c) can be placed.

Note that when printing of a predetermined number of sheets is completed, the paper feed tray (c) does not descend, and the entire rotary copying machine stops its operation.

In this embodiment, the paper feed tray (c) is configured to descend for a predetermined amount of time, but an encoder may be connected to the binion (to) and configured to descend by a predetermined distance.

(G) Effects of the Invention As mentioned above, in the present invention, the paper feed tray automatically lowers at the same time as the trial printing operation is completed, so the operator can immediately place the paper feed tray on the paper feed tray while looking at the sample printed material. Print paper can be adjusted.

Therefore, the operator does not need to manually lower the paper feed tray every time a test printing operation is performed, and printing preparations can be completed quickly and easily.

[Brief explanation of drawings]

The drawings all show one embodiment of the present invention, and FIGS. 1 and 2 are schematic configuration diagrams showing different aspects of a rotary copying machine, FIG. 3 is a front view of the main parts, and FIG. 4 is a block diagram. , FIG. 5 is a flowchart. (i)...Main body of rotary copying machine (printing machine), (c)...
・Printing paper, (c)...Paper feed table, (b)...Primary paper feed roller, (2)...Rank, (to)...Fill drive motor, (to)... Pinion, ■...CPU,
Q7)...Motor drive circuit, (c)...Trial printing operation end detection circuit. )Figure 4Figure 5

Claims (1)

[Claims] 1. In a printing machine having a trial printing operation mode, a paper feed table on which stacked printing sheets are placed, a lifting means for raising and lowering this paper feed table, and a The apparatus is characterized by comprising a paper feed roller that contacts the printing paper at the upper part, and a control means that operates the elevating means to lower the paper feed table when the end of the trial printing operation is detected. Printing machine paper feeding device. 2. The paper feeding device for a printing press according to claim 1, wherein the elevating means is controlled to operate for a certain period of time when the end of the trial printing operation is detected. 3. The paper feeding device of a printing press according to claim 1, wherein the paper feeding table is controlled to descend by a certain distance when the end of the trial printing operation is detected. 4. When the end of the trial printing operation is detected, the paper feed table is controlled so as to descend until the topmost printing paper is one inch away from the paper feed roller.Claims 1 to 3 A paper feeding device for a printing press according to any one of the above.