JPH0615258B2 - Paper feeder of printing machine - Google Patents

Description

The present invention relates to a sheet feeding device of a printing machine having a so-called trial printing operation mode, and in particular, the sheet feeding table is automatically lowered after the trial printing operation is completed. It is characterized by that.

(B) Conventional technology In a conventionally known printing machine, the paper feed tray does not automatically descend even after the test operation is completed.

Incidentally, there has already been proposed a copying machine in which a paper feed table is automatically lowered when a jam (paper jam phenomenon) occurs to facilitate jam processing (see Japanese Patent Publication No. 60-46709).

The invention described in the above publication is "an elevating device that elevates and lowers a transfer sheet in a paper feed tray or a cassette, and when a jam occurs, a jam is displayed to stop a copying function and the elevating device is driven to automatically use the device. When the transfer paper in the paper feed tray or the cassette is lowered to a position away from the paper feed roller, and the jammed paper is removed and the jam display is reset, the lifting device is driven to move the transfer paper to the topmost position. A copying machine that facilitates jam processing, characterized in that the copying machine is equipped with a control device that raises it to a position where it comes into contact with the paper feed roller and then enables copying. "

Therefore, the paper feed tray is lowered during jamming, but is not lowered during trial printing (since it is a copying machine, there is no trial printing operation mode other than the normal operation mode).

(C) Problems to be solved by the invention As described above, in the conventionally known printing press, the paper feed tray does not automatically descend even after the trial printing operation is completed, and the uppermost printing paper is fed. It remains pressed against the paper feed roller by the paper tray.

Therefore, the print sheet is not placed at a predetermined position on the paper feed table, and the print position is biased (to the right or left in the paper feed direction) or a skewing phenomenon occurs. In such a case, it was necessary to manually lower the paper feed tray, separate the print paper from the paper feed roller, and then realign or reposition the print paper.

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

Since the copying speed (printing speed) of the copying machine is slower than that of the printing machine, there is no test printing operation mode.
The above problems do not occur often.

(D) Means for Solving the Problems The present invention includes a paper feed table on which stacked printing sheets are placed, an elevating means for elevating and lowering the paper feed table, and at least the uppermost part at the time of paper feeding. A printing machine comprising: a paper feed roller that comes into contact with a printing paper; 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. It is a paper feeding device.

(E) Action In the present invention, when the trial printing operation is completed, the elevating means automatically operates to lower the paper feed tray, so that the pressing force of the uppermost printing paper against the paper feed roller is reduced or released. To 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 structure of the rotary copying machine will be described with reference to these drawings, and then the sheet feeding device will be specifically described.

(1) is the body of the rotary copying machine, which has a well-known cylindrical plate cylinder.
(2) is rotatably mounted. A support shaft (4) extending parallel to the rotary shaft (3) of the plate cylinder (2) is rotatably inserted in the vicinity of the peripheral side part of the plate cylinder (2). A plurality of hook-shaped set hooks (5) that can project in the centrifugal direction from the peripheral surface of the plate cylinder (2) are arranged along the extending direction. Further, a cam follower holding arm (6) is fixedly provided on a projecting portion of the support shaft (4) from a side end surface of the plate cylinder (2), and a cam follower (6) is provided near the free end of the arm (6). 7)
Is rotatably attached. Therefore, the set hook
(5) and the cam follower (7) are integrated to form the support shaft (4).
It is configured to be able to swing around. Although not shown, the set hook (5) is
The free end is biased by a spring so that it is biased toward the center of the plate cylinder (2) (the direction perpendicular to the rotation axis (3)).

Outside the side end surface of the plate cylinder (2), at a portion corresponding to the cam follower (7), a plate feeding cam (8) and a plate discharging cam (9) are provided.
The holding shaft (1) that is planted in the chassis (1) (not shown)
0) and (11) are mounted so that they can be slightly swung, respectively.
(8) and (9) are connected by a U-shaped link (12). A solenoid (14) is connected to the plate discharge cam (9) via a plunger (13). The edge of the plate feeding cam (8) facing the plate feeding section is at the longest distance from the center of the plate cylinder (2), and the edge of the plate discharging cam (9) facing the plate discharging section is also the plate cylinder.
The longest distance from the center of (2). (15) is the link (1
It is a tension spring of 2) which is provided on the opposite side across the center of the plate cylinder (2) and biases both cams (8) and (9) inward.

Thus, when the solenoid (14) is excited to perform suction operation, the cams (8) and (9) are separated from each other against the tension spring (15),
It moves from the position indicated by the chain double-dashed line in FIG. That is, the plate feeding cam (8) moves from the non-plate-positioning position to the plate-feeding position, and the plate-releasing cam (9) moves from the non-plate-releasing position to the plate-releasing position.

Therefore, when the cam follower (7) arrives at the plate feeding portion while the solenoid (14) is in the suction operation, the cam follower (7) contacts the plate feeding cam (8) and the set hook (5). ) Is projected and biased in the centrifugal direction from the peripheral surface of the plate cylinder (2). Further, when the cam follower (7) arrives at the plate discharge portion, as shown in FIG. 2, the set hook (5) is also moved in the centrifugal direction from the peripheral surface of the plate cylinder (2) by the plate discharge cam (9) in this case as well. Projective bias.

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

The plate supply section is provided with guides (17) and (18) for inserting the stencil sheet (16a) after plate making toward the plate cylinder (2).

Further, the plate discharge section is provided with a base paper storage box (20) in which a plate discharge claw (19) for peeling the stencil paper (16b) after printing from the plate cylinder (2) is fixed. In the base of the plate discharge claw (19), a pair of meshing gears (21) for storing the stencil sheet (16b) separated from the plate cylinder (2) in the sheet storage box (20).
(22) is provided. The base paper storage box (20) is attached to the main body (1) so that it can be inserted in the direction of the arrow.
(23) is a driving gear that drives the gears (21) and (22).

Below the raw paper storage box (20), a paper feeding device for feeding the printing paper (24) is provided. This paper feeder is
A paper feed table (25) that is mainly equipped with a large amount of printing paper (24) and is vertically movable, and the uppermost paper (25) that is located above the downstream end of the paper feed table (25). First pressed against 24)
It is composed of the next paper feed roller (26). Details of the paper feeding device will be described later.

At the downstream side of the primary paper feed roller (26), the printing paper (24) fed by the primary paper feed roller (26) is temporarily stopped, and then re-tried at timing. A secondary paper feed roller pair (27) (28) is provided for feeding.
(29) and (30) are a pair of paper feed guides.

At the lower end of the plate cylinder (2), a press roller (31) for pressing the printing paper (24) against the stencil sheet (16a) for printing.
Is pressed. Reference numeral (32) is a paper discharge tray for stacking and storing the printing paper (24) after printing.

Thus, at the time of plate feeding, between the guides (17) (18) of the plate feeding section, after inserting the downstream end of the stencil sheet (16a) after plate making, when starting the plate feeding operation, Solenoid as described above
(14) is excited and suction operation is performed. Then, the plate feeding cam
Since the plate (8) moves from the non-plate feeding position to the plate feeding position, when the plate cylinder (2) rotates clockwise (in the direction of the arrow) in that state, the cam follower (7) contacts the plate feeding cam (8). Then, the set hook (5) stands up (solid line position in Fig. 1). When the plate cylinder (2) further rotates in this state, the set hook (5)
6a) engages with the engaging hole (not shown), and the stencil sheet (16
A) is sequentially wound around the plate cylinder (2) from its downstream side.

The solenoid (14) is controlled so as to stop the suction operation before the set hook (5) reaches the plate discharge position, that is, before the cam follower (7) contacts the plate discharge cam (9). When the set hook (5) reaches the plate ejection position, the plate ejection cam (9) is moved to the non-plate ejection position by the spring (15). Therefore, the cam follower (7) does not contact the plate discharge cam (9), and the set hook (5) does not project and bias from the plate cylinder (2), so that the plate discharge operation is not executed.

In this way, the plate is fed and a predetermined number of printing papers (24) are printed.At this time, the plate feeding cam (8) is in the non-plate feeding position, and the plate ejection cam (9) is in the non-plate ejection position. However, the cam follower (7) is configured not to contact the cams (8) and (9).

When printing is finished and the plate is ejected, the cam follower (7) is used.
While moving between the plate supply cam (8) and the plate discharge cam (9), the solenoid (14) is excited again to perform suction operation, and the plate discharge cam (9) moves from the non-plate discharge position to the plate discharge position as described above. Move to. Then, the cam follower (7) comes into contact with the plate discharge cam (9), and the set hook (5) stands up while lifting its end while engaging with the stencil sheet (16a) (see FIG. 2). When the plate cylinder (2) further rotates in that state, the downstream side end of the stencil sheet (16a) (the end lifted by the set hook (5)) is peeled off by the plate discharge claw (19), and the gear (twenty one)
You will be guided to (22). The stencil sheet (16b) separated from the set hook (5) and guided is stored in the sheet storage box (20) by the gears (21) and (22).

Next, details of the power supply device, which is a main part of the present invention, will be described with reference to FIGS. 1 to 3. FIG. 3 is a partially enlarged front view showing a specific structure of the primary paper feed roller (26). The paper feed table (25) is slidably held by a guide (33) vertically provided on the main body (1). In addition, the paper tray (2
The rack (34) is fixedly installed in (5).
Is a motor (35) for driving the paper feed tray provided in the main body (1).
And meshes with a pinion (36) connected via a reduction gear. Therefore, when the pinion (36) rotates forward and backward, the paper feed table (25) moves up and down.

The primary paper feed roller (26) is provided in the vicinity of the free end of the roller holding arm (38) that is swingably attached to the holding member (37) fixedly provided inside the main body (1). It is configured to be rotatably mounted and to be given a rotational force by means (not shown). Further, an L-shaped actuator (39) is fixedly mounted on the roller holding arm (38), and the paper feed table (25)
Rise, the uppermost printing paper (24) abuts the lower part of the primary paper feed roller (26), and the roller holding arm (38) causes the support shaft (4
When it is rotated clockwise about (0), the actuator (39) operates the micro switch (41) mounted on the holding member (37) to drive the paper feed tray drive motor (3).
It is configured to stop the rotation of 5). The roller holding arm (38) is slightly biased counterclockwise by a spring (not shown).

A separating plate (42) for preventing double feeding of the printing paper (24) is pressed by a spring (43) below the primary paper feeding roller (26).

Next, the control circuit of the sheet feeding device will be described mainly with reference to FIG. 4 (block diagram). In this figure, (44) is C
A PU (Central Processing Unit), (45) is a memory (ROM) in which the operating time of the paper feed tray drive motor (35) in each operation mode is stored, and (46) is an interface. (47)
Is a drive circuit of the paper feed tray drive motor (35), (48) is a circuit that detects the end of the trial printing operation, (49) is a jam (paper jam) detection circuit of the recording paper (24), and (50) is Recording paper (2
This is a circuit that detects the presence or absence of 4).

In the present embodiment, when the occurrence of a jam is detected or the trial printing operation is finished, the printing paper (24) on the paper feed tray (25) is consumed even though the printing of the predetermined number of sheets is not completed. In this case, detection signals are output from the detection circuits (48) (49) (50), and the paper feed tray drive motor (35) rotates for a predetermined time in response to the detection signals. . Therefore, the paper feed table (25) is lowered by a predetermined size.

Next, the operation of this embodiment will be described with reference to FIGS. 4 and 5 (flow chart).

In the paper feed tray lowering routine, it is judged 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, and at the same time, the above-mentioned feeding is performed. The board drive motor (35) starts to operate. When the timer is subtracted and becomes 0, that is, the paper feed tray
It stops when (25) descends for 2 seconds.

Therefore, the primary paper feed roller (26) and the uppermost printing paper
A space for removing the printing paper (24) causing the jam is formed between itself and (24).

On the other hand, if the jam has not occurred, it is determined whether the trial printing operation has ended. If it is determined that the trial printing operation has ended, the timer is set to 0.5 seconds. At the same time, the paper feed tray drive motor (35) starts to operate. When the timer is decremented to 0, that is, when the paper feed tray (25) descends for 0.5 seconds, the timer stops.

Then, a slight gap is generated between the primary paper feed roller (26) and the uppermost printing paper (24). Therefore, it becomes possible to move and adjust the printing paper (24) on the paper feed table (25).

Also, when the trial printing operation is not completed and the printing paper (24) on the paper feed tray (25) is positioned at the predetermined position,
It is determined whether or not the predetermined number of prints have been completed, and if the predetermined number of prints have not been completed, the paper feed tray (2
5) When it is determined that all the above printing papers (24) have been fed (consumed), the timer is set to 3 seconds, and at the same time, the paper feed tray drive motor (35) starts operating. . When the timer is decremented to 0, that is, when the paper feed tray (25) descends for 3 seconds and reaches the vicinity of the bottom of the main body (1), it stops.

Then, the required number of sheets of printing paper can be placed on the paper feed tray (25).
A space in which (24) can be placed is formed.

When the specified number of sheets have been printed, the paper tray (25)
Does not descend, and the entire rotocopier stops its operation.

In the present embodiment, the paper feed table (25) is configured to be lowered for a predetermined time, but an encoder may be connected to the pinion (36) to be configured to be lowered by a predetermined dimension.

(G) Effect of the Invention As described above, in the present invention, the paper feed tray is automatically lowered at the same time when the trial printing operation is completed. Therefore, the operator can immediately see the printed matter on the paper feed tray while watching the printed matter. The printing paper can be adjusted.

Therefore, the operator does not have to manually lower the paper feed tray each time the trial printing operation is performed, and the printing preparation can be completed quickly and easily.

[Brief description of drawings]

Each of the drawings shows an embodiment of the present invention, FIGS. 1 and 2 are schematic configuration diagrams showing different aspects of a rotary copying machine, FIG. 3 is a front view of essential parts, and FIG. 4 is a block diagram. 5 is a flow chart. (1) …… Rotary copying machine (printing machine) body, (24) …… Printing paper, (25) …… Feeding stand, (26) …… Primary feeding roller, (34)
…… Rack, (35) …… Feeder board drive motor, (36) …… Pinion, (44) …… CPU, (47) …… Motor drive circuit,
(48) …… Pre-printing operation end detection circuit.

Claims (4)

[Claims] 1. A printing press having a trial printing operation mode,
A sheet feed table on which the stacked printing sheets are placed, an elevating means for raising and lowering the sheet feed sheet, a sheet feeding roller that abuts the uppermost printing sheet at the time of sheet feeding, and a trial printing operation is completed. And a control means for operating the elevating means to lower the paper feed table when the paper feed is detected. 2. The sheet feeding device for a printing press according to claim 1, wherein when the end of the trial printing operation is detected, the elevating means is controlled to operate for a fixed time. 3. The paper feeding device for a printing press according to claim 1, wherein when the end of the trial printing operation is detected, the paper feeding table is controlled to descend by a predetermined size. 4. When the end of the trial printing operation is detected, the paper feed tray is controlled so as to descend until the uppermost printing paper is separated from the paper feed roller. 4. A sheet feeding device for a printing machine according to any one of items 3 and 4.