JPS60220753A - Paper discharger of printer - Google Patents

Abstract

PURPOSE:To automatically adjust the interval of paper discharging units at an optimum position by a method in which the width of paper is detected only by placing the printing paper to be used on a paper supply base. CONSTITUTION:When paper P of a narrower width than the position of a detector is placed on a supply base, the signal S1 is at low level when a sensor 38 used is a photo sensor. The first judging circuit 55 sends out a signal to normally turn the pulley of a motor M during the period when the signal S1 is at low level. Two screw levers are each turned clockwise thereby, and both paper discharging units are mutually moved to the center. When the sensor 38 is moved and reaches the edge of the paper P, the signal S1 becomes of high level quickly by reflected light from the face of the paper. When detecting the variation of the level of S1, a timing circuit is operated by the circuit 55, and when the sensor 38 moves inwards about 5mm. from the edge of the paper P, the output of the driver is stopped and the motor M is stopped. Both the units can thus be stopped at optimum position.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a paper discharge device for a printing press, and more particularly, to a method for detecting the paper width when changing the size of printing paper used, especially in an offset printing machine. The present invention relates to a paper discharging device that automatically adjusts the interval between paper discharging units and that puts the machine into a non-operating state when the paper runs out during operation.

[Prior Art] As plate-making technology has been simplified in recent years, small-sized offset printing machines have become popular and are generally widely used as office machines. The structure of such a small offset printing press will be explained with reference to the side view of FIG. 1 as an example. In the figure, 10 is a plate cylinder, 11 is a blanket cylinder, and 12 is an impression cylinder, and the paper P on the paper feed table 13 is sent out by a feed roller 14, and the paper P is sent out by a gripper (not shown) provided on the impression cylinder 12. The tip is inserted and pressed against the blanket cylinder 11 by rotation of the impression cylinder 12, where offset printing is performed. After printing, the paper P passes through a paper discharge device 15, the details of which will be described later, and then the gripper of the impression cylinder 12 opens to release the leading end from the impression cylinder 12, and is then guided by a paper discharge mold 16.
The paper passes between the rollers 21 and 23 of the paper ejection device 15 and is ejected onto the paper ejection table 11.

The paper ejecting device 15 includes a pair of members including an arm and a roller, which are mounted so as to be integrally movable on a fixed shaft 18;
It is composed of a pair of paper ejection rings 24 that are movable on paper ejection rollers 23. That is, as shown in the figure, the fixed shaft 1
An arm 20 having a pressure roller 19 that presses the surface of the impression cylinder 12 is loosely fitted in the arm 8, and an arm 22 that has a pressure roller 21 that presses a paper discharge roller 23 is coaxially and loosely fitted to the arm 8. Both rollers 19.21 are respectively attached to opposite sides of both arms 20.22, and are arranged so as to be aligned in a straight line with respect to the traveling direction of paper P. On the other hand, two paper ejection rings 24 are movably fitted onto the paper ejection roller 23, and each of them is fitted with a pressing roller 21.
It is arranged so as to be on the outside of the sheet P, and performs what is called "waisting", which lightly creases both side edges of the sheet P when the sheet is ejected.

Its purpose is to make paper ejection smooth and easy. The paper ejecting device 15 is generally configured in this way, in part because the ink for offset printing has a high viscosity.
This is because when the gripper No. 2 opens and the leading edge of the paper P is released, the paper P is attached to the blanket cylinder 11 and rolled up, making it difficult to eject the paper.

The paper ejecting device of a conventional small-sized offset printing machine has the above-mentioned configuration, so whenever the user wants to change the size of the printing paper from, for example, B4 to A4, he first feeds the paper P, and then Stop the leading end at the position of the paper ejection device 15, manually adjust the position of each paper ejection ring 24 according to the width of the paper, and then remove both arms 20 that are integrated.
．． 22 by hand to adjust the distance between the pressing roller 21 and the paper ejection ring 24 to the optimum width of the cuff (usually about 1 cm). This work is
Not only does it require considerable skill to adjust the positions of a total of four members, but since the fixed shaft 18 is located under the rubber cylinder 11, it is easily soiled by etchant, ink, etc., and therefore it is not suitable for work in an office. It was extremely unpleasant work.

For this reason, a device capable of performing the above-mentioned position adjustment via a mechanical mechanism has been proposed in Japanese Patent Laid-Open No. 139962/1983. FIG. 2 is a partially cutaway front view of a known sheet discharge device proposed by the present invention, in which the same members as those explained in FIG. 1 are given the same reference numerals.

As is clear from the figure, in this device, one end of the arm 22 to which the pressing roller 21 is attached is a screw block 25, and the arm 20 having the pressing roller 19 is loosely fitted into this screw block 25 so as to be able to swing. There is. Both screw blocks 25 are screwed into separate screw rods 26, and the screw rods 26 are connected to an external operating handle (not shown) via gear trains 27 and 28. Although not shown in this figure, in order to adjust the position of the paper ejection ring 24, this device is provided with a combination of a screw block and a screw rod for each paper ejection ring 24, and a separate gear train and screw rod are provided for each paper ejection ring 24. It is connected to the above operating handle via a sprocket and a chain.

In order to adjust the position with this device, by turning a handle (not shown), a screw rod (not shown) for moving the gear train 27 and the left side discharge ring 24 rotates forward or backward depending on the direction of rotation of the handle. Arm 2 on the left in the diagram
0.22 and the paper ejection ring 24 in the left and right direction.

When the handle (not shown) is pulled out in the axial direction and rotated, the gear clutch (not shown) switches, and this time, via the gear train 28, sprocket, and chain, the arm 20, 22 on the right side of the figure and the paper ejection ring 2 are connected to each other via the gear train 28, sprocket, and chain.
4 moves in the left and right directions in the figure depending on the direction of rotation of the handle. Thus, this known device can be adjusted much more easily than conventional devices.

However, even with this known device, prior to use, the position is adjusted according to the width of the paper by manually operating a handle by feeding the paper and aligning it with the leading edge of the paper.
It is no different from conventional equipment in that it requires a considerable amount of skill. Furthermore, a large number of complicated transmission mechanisms including a gear train are required for position adjustment, and the manufacturing cost of the device is therefore high.

[Problems to be Solved by the Invention] Therefore, the first purpose of this invention is to place the printing paper to be used on the paper feed tray, detect the width of the paper, and adjust the spacing between the paper ejection units. An object of the present invention is to provide a paper discharge device for a printing press that automatically adjusts to an optimal position.

The second object of this invention is to detect not only when there is no paper on the paper feed table, but also when there is no paper during printing work, to issue an alarm and to put the machine into a non-operating state. An object of the present invention is to provide a paper discharging device for a printing press that can perform the following operations.

[Means for Solving the Problems] In order to achieve the first object mentioned above, the apparatus of the present invention (ζ) is equipped with a rotatable screw screw provided on the paper feed table side of the impression cylinder. a pair of paper ejecting units that are screwed together via a screw block to a rotatable screw punch that is provided on the paper ejecting side of the impression cylinder and has threaded parts that wind in different directions from the center to both sides; , comprising a motor that rotates both screw punches synchronously, and a control device that controls the rotation of the motor based on a signal from a detector of a detection device.
In order to achieve this purpose, in addition to the above-mentioned features, the device of the present invention processes the signal from the paper detection device in the control device to issue an alarm when the paper on the paper feed tray runs out, and also to deactivate the machine. It is also characterized by emitting a signal to set the state.

Embodiment FIGS. 3 to 6 show an embodiment of the present invention, and the same parts as in the conventional apparatus are given the same reference numerals. FIG. 3 is a perspective view showing the main parts of an embodiment of the present invention, FIG. 4 is a front view of the paper ejecting device portion of the present invention viewed from the direction of the white arrow in FIG. 3, and FIG. A cross-sectional view along line A-A in Figure 4,
FIG. 6 is a block diagram of the control circuit. As is clear from the figure, a paper feed tray 13 is attached to one side of the impression cylinder 12, and a paper discharge device 15 is attached to the other side of the impression cylinder 12, respectively, to the frame 30.

A pair of paper guides 31 are provided on the paper feed tray 13 via an interlocking mechanism such as a suitable link device, so that when one moves, the other also moves in response, so that the center line of the paper P is 1. It is arranged to be positioned exactly on the center line of the paper feed table 13.

Further, the paper feed table 13 is swingably supported by the frame 30 by a shaft 32, and by moving a lever (not shown),
It is designed to swing from the preparation position to the printing position shown in FIG. There is a support girder 33 on the frame 30 on the side of the paper feed table 13.
is built between both walls, and near the center is a Brown 1-
34 is fixedly installed. A screw punch 36 is disposed below the support girder 33 and parallel to the support girder 33, one end of which is supported by a bracket 34 and the other end of which is connected to a toothed pulley 35 through the frame wall. Further, a detection device 37 is suspended on the receiving girder 33, and the detection device has a detector 38 at the lower end for detecting and covering the paper, and also detects the paper through a screw block 39 screwed into the screw punch 36. It is said that it can be moved on 33.

On the side of the frame 30 where the paper ejection device 15 is located, there is a paper ejection shaft 40 whose one end is supported by the frame and whose other end is connected to a drive gear through the frame wall. A groove 41 is cut in the direction. Further, above and parallel to the paper ejection shaft 40, a screw punch 42 having threaded portions with different winding directions from the center to both sides is pivotally supported at one end by the frame 30.
The other end passes through the frame wall and is connected to a toothed pulley 43. Above and parallel to the screw punch 42 is a suppression guide rod 44, the ends of which protrude through an elongated hole formed in the frame 30, and are elastically supported downward by a spring 45. There is.

A pair of left-right symmetrical paper discharge units 46 having the same structure are formed by each of the paper discharge shaft 40, screw punch 42, and pressing guide rod 44.
is supported. The paper ejection unit 46 rotatably supports a pressing roller 19 at one end of a holder 47 shaped as shown in FIG. is rotatably supported. The above-mentioned principle is that the paper ejection roller 48 is MIMed to the paper ejection shaft 40, and the locking bin 49 is connected to the paper ejection shaft 40.
This engages the groove 41 and rotates as the paper ejection shaft 40 rotates. The screw block 25 screwed into the screw punch 42 near the middle f of the holder 47 is loosely fitted so as to have a slight gap 50 (FIG. 5) with respect to the swinging direction of the paper discharge units 1 to 46. Furthermore, an arm 22 rotatably supporting the press roller 21 is loosely fitted into the screw block 25 so that the press roller 21 is pressed onto the paper ejection roller 48 by its own weight. It has become. A pressing guide rod 44 is loosely fitted and passes through the holder 47 near the pressing roller 19, and due to the tension of the spring 45 and the play in the gap 50, the pressing roller 19 is pressed onto the circumferential surface of the impression cylinder 12. There is.

The winding direction of the screws in the screw punch 36 and the screw punch 42 is such that when the toothed pulleys 35 and 43 each rotate clockwise in the figure in FIG. 3, the detection device 37 moves toward the bracket 34. , both paper discharge units 46 are arranged to move toward the center of each other so as to narrow the distance between them, and when both toothed pulleys rotate counterclockwise, this is reversed. ing. Further, both the toothed pulleys 35 and 43 are synchronously rotated in the same direction via a toothed belt 52 by a toothed pulley 51 of a motor M (not shown) which can rotate in forward and reverse directions.

The rotation of the motor M is controlled by a control circuit 53 shown in a block diagram in FIG. 6 in response to a signal SI from the detector 38. The control circuit 53 includes a selector circuit 54,
It is composed of a first judgment circuit 55 and a second judgment circuit 56, and in an initial state, the signal S1 from the detector 38 is input to the first judgment circuit 55 via the selector circuit 54. The operation of each circuit in the control circuit 53 will be explained in detail below through the operation explanation of the embodiment of the present invention.

When using the embodiment shown in FIGS. 3 to 6, first turn on the main switch (not shown). As a result, the control circuit 53 is energized and placed in an initial state, and at the same time, each electrical component within the device is also placed in a ready state. Next, after completing the preparation work such as loading the original printing plate onto the plate cylinder 10, the paper P is placed on the paper feed tray 13 and the paper guide 31 is adjusted to match the width of the paper.

First, regarding the apparatus shown in FIG. 3, a case will be described in which a sheet P whose sheet width is narrower than the illustrated position of the detecting device 37 is placed on the sheet feeding tray 13. When a lever (not shown) connected to the shaft 32 is rotated to move the paper feed tray 13 to the printing position shown in FIG. 3, a switch linked to the lever is turned on and the detector 3
8 outputs a signal S1. In this case, the detector 38 is located outside the paper P, and if the detector is a photo sensor, for example, it does not receive the reflected light from the paper P, so the signal Sl
is at a low level. First judgment circuit 5 in control circuit 53
5 is a toothed pulley 5 of the motor M that is directed toward the driver while the signal S1 received via the selector circuit 54 is at a low level.
Outputs a signal that causes the motor to rotate forward (clockwise in the figure).

As a result, the toothed belt 52, both toothed pulleys 35 and 4
3, the two screw punches 36 and 42 each rotate clockwise to move the detector 38 toward the bracket 34, and both paper ejecting units 46 move toward the center relative to each other. The spacing is narrowed at the same time. When the detector 38 moves in this way and reaches the edge of the paper P, the signal S1 suddenly changes to a high level due to the light reflected from the paper surface. When the first determination circuit 55 in the control circuit 53 detects a change in the level of the signal Sl, it activates an internal timing circuit, and when the detector 38 moves approximately 5n+m inward from the edge of the paper P, The output to the driver is stopped, and a switching signal S2 is output to the selector circuit. As a result of the output to the driver being stopped, the motor M is stopped, the detector 38 is located approximately 5m+++ inside the edge of the paper P, and both paper ejection units 46 are mounted such that the side edge of the paper ejection roller 48 is They each stop at optimal positions that match the positions of both side edges of the paper P, and are ready to start printing at any time. On the other hand, the switching signal S
The selector circuit 54 receiving the signal S2 switches the detection signal S1 from the detector 38 to the second judgment circuit 56. The operation of the second determination circuit 56 is the same as when the paper P is replaced with a wider one, which will be described next, and will be explained in its entirety later.

Next, a case will be described in which the paper P is replaced with a paper P having a wider paper width than the paper previously used.

The example shown in FIG. 3 corresponds to such a case, but the paper P is placed on the paper feed tray 13 (not shown), and a lever (not shown) is rotated to move the paper feed tray 13 to the position shown in FIG. 3. When the printing position is set to , the detector 38 will be located considerably inside the side edge of the paper P, where the width of the paper was previously narrow. Therefore, when the switch linked to the lever is turned on, the detector 3
8 is a high level detection signal S due to reflected light from the paper surface
1 is input to the control circuit 53. The first in the control circuit 53
When the judgment circuit 55 is reset to the initial state and a low level detection signal S+ is input, it outputs an output that rotates the shaft M in the forward direction as described above. When 81 is input, an output that causes the motor M to rotate in the reverse direction (counterclockwise in the figure) is issued to the driver.

Therefore, both teeth (=l pulleys 35 and 43 and both screws 36 and 42 rotate in the opposite direction, the detector 38 moves toward the side edge of the paper P, and at the same time, both paper discharge units 4G widen the distance between them. Thus, when the detector 38 passes the side edge of the paper P, the reflected light from the paper surface suddenly disappears, and the level of the signal SI drops rapidly.

When the first judgment circuit 55 in the control circuit 53 detects a change in the level of the signal S1, it immediately issues a signal to stop driving the motor M, and then activates an internal timing circuit and causes the motor M to rotate in the normal direction. When the signal is emitted and the detector 38 returns to about 5ml1 inside the edge of the paper P, the output to the driver is stopped, the motor M is stopped again, and a switching signal S2 is output to the selector circuit 54.

As a result, both paper ejecting units 46 are adjusted to be in the optimal position to start printing at any time, as described above. On the other hand, the selector circuit 54 receiving the switching signal S2 switches to input the detection signal S+ to the second determination circuit 56 in the same manner as described above.

As described above, when the printing operation is started after both paper ejection units 46 are at the optimum position, the detector 38 generates a high level detection signal due to the reflected light from the paper P on the paper feed table 13 during the operation. S+ is input to the second judgment circuit 56 and continues. In this state, if the paper P runs out before printing a predetermined number of sheets, the detection signal S1 suddenly changes from a high level to a low level. When the level of the detection signal S+ becomes low, the second judgment circuit 56 outputs an alarm signal S3 to the driver to activate the alarm A, and also outputs a stop signal @S4 to the machine parts control circuit 57. The machine parts control circuit 57 that receives the stop signal S4 issues a signal to stop each part in the machine in a predetermined order, and outputs a reset signal S5 to the selector circuit 54 when the machine stops. The selector circuit 54 that has received the reset signal S5 returns all of its internal parts to the initial state, and also transfers the reset signal S5 to the both-side cut-off circuits 55 and 56, and thus the control circuit 5
3 is all reset to the initial state. From the above explanation, when the operator places less paper P than the predetermined number of sheets to be printed on the paper feed table 13 and starts work by mistake, the detection device 37 of the present invention It will be understood that this is a safety device that not only detects the width of the paper P, but also detects the presence or absence of the paper P during operation. Therefore, if enough paper P is placed on the paper feed table 13, the alarm signal S3 and stop signal S4 will not be output even after printing a predetermined number of sheets, so that the operator can replace the plate. When the next printing operation begins, the control circuit 53
The paper P continues to be detected by the detection signal S+ from the detector 38.
It operates as a safety device to detect the presence or absence of

In FIG. 3, a detection device sensor 58 such as a microswitch is attached to the bracket 34 as another safety device. If the operator accidentally operates a lever (not shown) to set the paper feed tray 13 to the operating position without placing the paper P on the paper feed tray 13, the detector 38 detects the paper P on the paper feed tray 13. In this case, since there is no paper P on the paper feed tray 13, a low level detection signal S1 is output. As described above, when the low-level detection signal S1 is first input to the control circuit 53 in the initial state, the first judgment circuit 55 outputs an output that causes the motor M to rotate in the forward direction. Start moving toward the bracket 34. In this case, since there is no paper P, the detection signal S1 does not change to a high level, so the detection device 37 ends up coming into contact with the bracket 34.

Just before this contact occurs, the detection device sensor 58 is activated and issues a signal. This signal is the first judgment path 55
The first judgment circuit 55 uses this signal to issue a signal to stop the motor M, and also outputs a switching signal S2 to the selector circuit 54. When the selector circuit 54 receives the switching signal S2, it immediately switches the sensor signal SI to be input to the second judgment circuit 56, but since the sensor signal S+ is at a low level,
The second judgment circuit 56 immediately outputs an alarm signal S3 that activates the alarm Δ and a stop signal S4. Thus, the motor M stops and the alarm A is activated, so the operator becomes aware of his own malfunction, and the detection device 37 detects the bracket 3.
This prevents damage caused by contact with 4. On the other hand, since each part of the machine is not yet in operation, the stop signal S4 is converted into a reset signal S5 in the machine parts control circuit 57, and the inside of the control circuit 53 is reset to the initial state.

Although the illustrated embodiment has been described above, the present invention is of course not limited to the illustrated example and can be modified in various ways. −
For example, instead of being activated by a lever, the paper feed tray 13 may be in a cassette format, and the switch for the signal SI of the detector 38 may be opened and closed by attaching and detaching the cassette. In addition, in the case of an elevator system capable of stacking a large number of sheets, a switch is provided to detect when the paper P reaches the paper feeding position, so this switch can be used as a double switch for the signal S+. As such, other modifications will be readily apparent to those skilled in the art.

[Effects of the Invention] As is clear from the above explanation, according to the present invention, the following excellent effects can be obtained.

(1) Just by placing paper on the paper feed table, the detection device detects the side edges of the paper and automatically adjusts the distance between both paper output units to the optimal position according to the paper width. can do.

(2) After completing the position adjustment of both paper output units, the detection device constantly detects the presence or absence of paper on the paper feed tray, and if paper runs out during printing, it will immediately issue an alarm and start the machine. Since the printer stops, the operator can realize his/her mistake, replenish paper, and print the required number of copies.

(3) Since the position adjustment of the paper ejecting device, which requires a great deal of skill, is automatically performed, even beginners, including female office workers who are inexperienced in handling machines, can easily carry out printing work.

(4) Since the distance between the paper ejecting units can be adjusted without touching the paper ejecting unit, which is easily soiled, - stamps can be used, it is possible to work comfortably in the office.

[Brief explanation of the drawing]

Figure 1 is a side view of a conventional offset printing machine;
The figure is a partially cutaway front view of a known sheet discharge device, FIG. 3 is a perspective view of essential parts of an embodiment of the present invention, and FIG. 4 is a sheet discharge device seen from the direction of the white arrow in FIG. 3. 5 is a sectional view taken along line A-A in FIG. 4, and FIG. 6 is a block diagram of the control circuit. 12... Impression cylinder 13... Paper feed table 15... Paper discharge device 25... Screw block 36... Screw punch 37.
...Detection device 38...Detector 42...Screw pestle 4
6... Paper discharge unit 53... Control circuit M... Motor A... Alarm patent applicant Duplo Manufacturing Co., Ltd. Figure 1 Figure 2

Claims (2)

[Claims] (1) A detection device 37 screwed onto a rotatable screw rod 36 provided on the sheet feed table 13 side of the impression cylinder 12, and a detection device 37 screwed onto a rotatable screw rod 36 provided on the paper feed table 13 side of the impression cylinder 12; a pair of paper ejection units 46 that are screwed together via a screw block 25 to a rotatable screw rod 42 having threaded portions in different directions; a motor M that synchronously rotates both screw rods 36 and 42; A paper discharge device for a printing press, comprising a control circuit 53 that controls the rotation of the motor M based on a signal from a detector 38 of a detection device 31. (2) When there is no paper on the paper feed tray 13, the control circuit 53 issues a signal to activate the alarm A based on a signal from the detector 38, and also issues a signal to stop the machine. A paper discharge device for a printing press according to claim (1).