JP6286166B2 - Ink supply device for printing press - Google Patents

Description

  The present invention relates to an ink supply apparatus for a printing press, and more particularly to an apparatus for supplying ink from an ink fountain through an ink fountain roller, an ink call roller, and a plurality of ink kneading rollers to a printing surface.

  As this type of ink supply device, a plurality of ink call rollers divided in the length direction of the ink fountain roller are arranged in the vicinity of the ink fountain roller constituting the ink fountain, and each ink call roller is an ink fountain roller. Can be individually switched between a calling position that contacts the ink and a non-calling position that is separated from the ink fountain roller, and the ink is called by changing the position of the required ink calling roller at each predetermined call timing. For each calling roller, the circumference of the ink that is called from the ink fountain roller to the ink calling roller is controlled by controlling the rotation angle of the ink fountain roller from the contact with the ink fountain roller to the separation. Is known (Patent Document 1). The rotation angle of the ink fountain roller is controlled by controlling the time from the output of the switching command to the calling position to the ink calling roller until the output of the switching command to the non-calling position.

  In this apparatus, the ink that has come out of the ink fountain onto the surface of the ink fountain roller is transferred to the ink call roller while the ink call roller is switched to the call position, and the ink transferred to each ink call roller. Is transferred to the ink kneading roller while the ink calling roller is switched to the non-calling position.

  By controlling the circumferential length of the ink that is called for each ink call roller as described above, the amount of ink supplied to the ink kneading roller, that is, the printing surface, is controlled for each ink call roller.

  The reason why the ink amount is controlled for each ink calling roller is that the optimal ink amount varies depending on the position in the width direction depending on the pattern of the printed material. The ink amount for each ink calling roller is the pattern area ratio of the printed material. Is set according to

  In the conventional ink supply apparatus as described above, the circumferential length of the ink to be called to the ink calling roller corresponds to the rotation angle of both ink rollers corresponding to the rotation angle of the ink fountain roller from when the ink calling roller contacts the ink fountain roller. The ink call roller is controlled so as to be long (control contact length).

  In the case of color change at the time of plate replacement, after printing, appropriate printing is performed by supplying ink corresponding to the pattern area after plate replacement. When changing the plate, if the color is not changed, the cleaning may be performed or the cleaning may not be performed. Printing is performed by supplying ink corresponding to the pattern area after the plate exchange, when the plate is exchanged without color change, with or without washing.

JP 2000-141610 A

  When the plate is not changed when the plate is not changed, when the printing is performed by supplying ink corresponding to the pattern area after changing the plate, the density is stabilized, as in the case of performing the cleaning. Tend to take time.

  An object of the present invention is to provide an ink supply apparatus for a printing press that can solve the above-described problems and can stabilize the density at the time of printing after plate replacement.

In the ink supply device of the printing press according to the present invention, a plurality of ink calling rollers divided in the length direction of the ink fountain roller are arranged in the vicinity of the ink fountain roller constituting the ink fountain, It is designed to be switched individually between the calling position that contacts the ink fountain roller and the non-calling position that contacts the ink kneading roller away from the ink fountain roller, and the required ink calling roller for each calling timing at a predetermined interval. Ink is transferred by switching the position of the ink and ink is transferred from the ink fountain roller to the ink kneading roller, and the rotation angle of the ink fountain roller from the contact with the ink fountain roller to the separation is determined for each ink call roller. By controlling, call from ink fountain roller to ink call roller In the ink supply device of a printing press designed to control the perimeter of the ink, when changing the plate, the pattern area before the plate change and the pattern area after the plate change are compared for all ink call rollers. If the pattern area increases after plate replacement, additional ink kneading is performed, and if the pattern area decreases before plate replacement, the operation of the ink calling roller stops for a certain period of time.
The pattern area before the plate change is A%, the ink amount (%) before the plate change is Y + AZ, the pattern area after the plate change is B%, and the ink amount (%) after the plate change is Y + BZ. The following operation is performed according to the positive / negative of the difference (B−A) Z (%).

  (B-A) When Z> 0, Z additional kneading is performed.

  (B−A) When Z <0, (A−B) Z / B ink calls are stopped.

  As a cause of the time taken for the color to stabilize when changing the plate, if the plate area before the plate change is large, the amount of ink held in the roller group (ink call roller and multiple ink kneading rollers) is large. Therefore, if the printing density is high and slowly decreases to a stable density, and the plate area before plate change is small, the amount of ink held in the roller group is small. This is thought to be due to the stable concentration.

  According to the ink supply device of the printing press of the present invention, the ink amount held in the roller group before the plate replacement is compared with the ink amount necessary for the roller group after the plate replacement, and the ink amount after the plate replacement is If it increases, temporarily add ink, and if the amount of ink after plate change decreases, temporarily stop the ink supply, so that it takes time to reach a stable density after plate change. Can be shortened.

  When the rotation angle of the ink fountain roller from when the ink call roller contacts the ink fountain roller until it leaves is called the “contact rotation angle”, the contact rotation angle is controlled by the command for switching the call position to the ink call roller. This is performed by controlling the time from the output of the (contact command) to the output of the switching command to the non-calling position (non-contact command).

  The ink held by the ink call roller at the time of stable printing is the ink with uniform thickness (Y) from the end of the ink call roller and the ink with the thickness proportional to the picture area of the printed material (proportional It is considered that the constant is Z). Therefore, if the pattern area before the plate replacement is A%, the ink amount (%) held before the plate replacement is Y + AZ (%), and if the pattern area after the plate replacement is B%, after the plate replacement The retained ink amount (%) is Y + BZ (%). Therefore, the difference before and after the plate exchange is (BA) Z (%).

  Since B> A and B <A, there are cases where the difference is a positive or negative value. Here, different operations are performed depending on whether the difference is positive or negative.

  When the difference (B−A) Z> 0, the additional ink kneading is performed with the number of ink kneadings being the proportional number of Z times. The percentage of ink kneading is (BA) (%). Thereby, the density of the command value can be reached in a short time, and the density of printing can be stabilized.

  On the other hand, when (B−A) Z <0, the ink call is stopped for a predetermined time. The condition for stopping the ink call is that (A-B) Z / B ink calls are stopped. Thereby, the density of the command value can be reached in a short time, and the density of printing can be stabilized.

  In this way, when the plate is changed, the density of the command value after the plate change is reached in a short time in both cases where the difference (B−A) Z> 0 and (B−A) Z <0. The concentration of can be stabilized.

  A normal operation in which ink is called each time at each call timing and an intermittent operation in which the number of calls is smaller than that in the normal operation are performed. B is equal to or less than the intermittent operation percentage and (B−A) Z <0. In this case, it is preferable to stop the ink calling for {(A−B) Z / B} × C / B times.

  By doing so, even if intermittent operation is performed, the density of the command value after plate replacement can be reached in a short time, and the density of printing can be stabilized.

  According to the ink supply device of the printing press of the present invention, as described above, even if the difference between before and after the plate replacement is positive or negative, the command value density after the plate replacement is reached in a short time, and printing is performed. The concentration of the feed can be stabilized.

FIG. 1 is a schematic side view of a main part of an ink supply device of a printing press showing an embodiment of the present invention. FIG. 2 is a partially cutaway plan view of the ink transfer roller unit of FIG. FIG. 3 is a cross-sectional view of FIG. FIG. 4 is a flowchart showing a main part of control in the ink supply apparatus.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 is a left side view schematically showing a part of an ink supply device of a printing press, FIG. 2 is a partially cutaway plan view showing an enlarged part of FIG. 1, and FIG. 3 is an enlarged cross-sectional view of FIG. FIG. In the following description, the right side of FIG. 1 and FIG. 3 (lower side of FIG. 2) is the front, the left side of FIG. 1 and FIG. 3 (upper side of FIG. 2) is the rear, and the left and right when viewed from the front are left and right. .

  As shown in FIG. 1, an ink fountain roller (41) is arranged so as to be close to the rear end portion of the ink fountain member (40), thereby forming an ink fountain (42), and an ink fountain member (40 ) And an ink path (43) having a predetermined gap is formed between the rear end portion and the surface of the ink fountain roller (41).

  The first ink kneading roller (44) of the plurality of ink kneading rollers (44) (46) is arranged behind the ink fountain roller (41), and the ink fountain roller (41) and the ink kneading roller (44) are arranged. In between, the ink calling roller unit (45) is disposed adjacent to both. As shown in FIG. 2, the roller unit (45) is an aggregate of a plurality (seven in the drawing) of ink calling rollers (15) divided in the axial direction of the rollers (41) and (44). Ink calling rollers (15) are arranged at small intervals in the axial direction. The axes of these rollers (15) (41) (44) are parallel to each other and extend in the left-right direction. The ink fountain roller (41) and the ink kneading roller (44) are rotatably supported by the frame (7) of the printing machine, and are continuously driven in the direction of the arrow in FIG. Rotated. For example, the rotation speed of the ink fountain roller (41) is about 1/10 of that of the ink kneading roller (44).

  The left and right ends of the linear support member (6) parallel to the rollers (41) and (44) are fixed to the frame (7), and a plurality of movable members (8) are attached around the support member (6). Yes. The support member (6) has a prismatic shape having a slightly larger front-rear width than a vertical width. The movable member (8) has a short cylindrical shape, and the movable member (8) is formed with a relatively large square hole (9) penetrating in the axial direction. A plurality of movable members (8) are arranged in the axial direction between a pair of short cylindrical fixed members (10) fixed to the frame (7) so as to face each other and penetrated through the support member (6). The support member (6) is passed through the hole (9) of the movable member (8). The vertical width of the hole (9) of the movable member (8) is substantially equal to the vertical width of the support member (6), and the upper and lower surfaces of the hole (9) are in sliding contact with the upper and lower surfaces of the support member (6). Further, the front and rear width of the hole (9) is slightly larger than the front and rear width of the support member (6), and the movable member (8) has a rear surface of the hole (9) with respect to the support member (6). The front end position in contact with the rear surface and the rear end position in which the front surface of the hole (9) contacts the front surface of the support member (6) can be moved back and forth. On the upper surface of the hole (9) of the movable member (8) that is in sliding contact with the support member (6), a corner groove (11) is formed over the entire length of the movable member (8).

  As will be described later, each movable member (8) is positioned in the axial direction with respect to the support member (6), and between the movable members (8) and between the fixed members (10) at both ends, A slight gap is provided in the axial direction. Therefore, each movable member (8) can move individually in the front-rear direction with respect to the support member (6).

  An inner ring of a ball bearing (12) that is a rolling bearing is fixed to the outer periphery of each movable member (8). A metal sleeve (14) is fixed to the outer periphery of the outer ring of each ball bearing (12), and a rubber thick cylindrical ink call roller (15) is fixed to the outer periphery of the sleeve (14).

  A short cylindrical dust-proof member (16) is fitted between the outer peripheries of adjacent movable members (6). The dust-proof member (16) is made of an appropriate rubber-like elastic material such as natural rubber, synthetic rubber, or synthetic resin, for example, and flange portions (16a) that slightly protrude inward are integrally formed at both ends thereof. These flange portions (16a) are fitted into annular grooves (17) formed on the outer peripheral surface of the portion near the left and right ends of the movable member (8), whereby the dustproof member (16) is moved to the movable member (8). It is fixed to. A similar dustproof member (16) is fitted between the outer peripheries of the movable member (8) at the left and right ends and the fixed member (10) adjacent thereto.

  On the support member (6) side between each movable member (8) and the support member (6), a roller position switching device (19) for switching the position of the ink calling roller (15) is provided as follows. .

  A cylinder portion (20) is formed by forming a hole extending from the front to the rear a little at the portion of the support member (6) corresponding to the axial central portion of the movable member (8), and from the rear surface to the front a little. An extended spring accommodating hole (21) is formed. The center of the cylinder part (20) and the center of the spring accommodating hole (21) are on one straight line in the front-rear direction near the center of the movable member (8) in the vertical direction. A short cylindrical piston (22) is inserted into the cylinder part (20) through an O-ring (23) so as to be slidable back and forth. A ball (24) as an urging member is slidably inserted in the spring accommodating hole (21), and a compression coil spring (25) that urges the ball backward is inserted.

  Recesses (26) and (27) are formed on the front surface of the hole (9) of the movable member (8) facing the center of the piston (22) and the rear surface of the hole (9) facing the center of the ball (24), respectively. Is formed. The width of each recess (26) and (27) in the axial direction of the movable member (8) is constant. The cross-sectional shape of each of the recesses (26) and (27) in the cross section orthogonal to the axis of the movable member (8) is uniform, and forms an arc shape centering on a straight line parallel to the axis. A taper-shaped protrusion (22a) is formed at the center of the end face of the piston (22) facing the recess (26), and the protrusion (22a) is fitted into the recess (26). Note that the length of the piston (22) excluding the protrusion (22a) is slightly shorter than the length of the cylinder part (20), so that the protrusion even when the piston (22) is most retracted into the cylinder part (20). Most of (22a) protrudes from the front surface of the support member (6). On the other hand, a part of the outer periphery of the ball (24) is fitted in the recess (27).

  At the rear part of the support member (6), the ball (24) is always brought into pressure contact with the rear surface of the hole (9) of the movable member (8) by the elastic force of the spring (25), and the ball (24) has an outer periphery. The portion is fitted into the recess (27) and is brought into pressure contact with the front and rear edges of the recess (27). On the other hand, at the front part of the support member (6), the front surface of the support member (6) or the piston (22) is brought into pressure contact with the front surface of the hole (9) of the movable member (8), and the protrusion ( Most of 22a) is in the recess (26). In this way, most of the protrusion (22a) of the piston (22) and a part of the ball (24) are always fitted in the recesses (26) and (27), so that the support member (6) The movable member (8) is positioned in the axial direction.

  The support member (6) is formed with a circular air supply hole (28) extending in the axial direction from the left end and closed in the vicinity of the right end, and the left end opening end of the hole (28) is connected through an appropriate pipe. Connected to a compressed air source (29).

  A switching valve (solenoid valve) (30) is mounted on the upper surface of the supporting member (6) facing the groove (11) of the movable member (8), and the two ports of the switching valve (30) are connected to the supporting member ( The air supply hole (28) and the cylinder part (20) communicate with each other through the communication holes (31) and (32) formed in 6). Further, the electric wire (33) of the switching valve (30) is drawn out through the groove (11) and connected to the control device (34).

  In a state where the switching valve (30) is energized (on state), the cylinder part (20) is connected to the air supply hole (28) via the switching valve (30), and in a state where the energization is stopped (off state) The cylinder part (20) is communicated with the atmosphere through the switching valve (30). Then, by individually switching the energization state of the switching valve (30) of each switching device (19) by the control device (34), the position in the front-rear direction of each ink calling roller (15) is switched individually.

  When the switching valve (30) is switched to the OFF state, the cylinder (20) is brought into communication with the atmosphere, so that the piston (22) can move freely within the cylinder (20). For this reason, the movable member (8) is moved to the rear side via the ball (24) by the spring (25). As a result, the movable member (8) and the ink calling roller (15) are switched to the rear end position (non-calling position), and the ink calling roller (15) is separated from the ink fountain roller (41) and the ink kneading roller (44 ).

  When the switching valve (30) is switched on, the cylinder part (20) communicates with the air supply hole (28) and further through the compressed air source (29), so that the cylinder part (20) is compressed. Air is supplied. For this reason, against the force of the spring (25), the piston (22) protrudes forward from the support member (6), and thereby the movable member (8) is moved forward. As a result, the movable member (8) and the ink calling roller (15) are switched to the front end position (calling position), and the ink calling roller (15) moves away from the ink kneading roller (44) and presses against the ink fountain roller (41). To do.

  A position switching detection sensor (35) composed of a magnetic sensor is fixed in an embedded manner on the lower surface of the support member (6) that is in sliding contact with the bottom wall of the hole (9) of the movable member (8), and a movable member ( A permanent magnet (36) is fixed in an embedded manner to the bottom wall of the hole (9) of 8). The lower surface of the sensor (35) is flush with the lower surface of the support member (6) or slightly inward (upper side). The upper surface of the permanent magnet (36) is flush with the bottom wall surface of the hole (9) of the movable member (8) or slightly inside (lower). In the state where the movable member (8) is switched to the rear end position, the sensor (35) is opposed to the central portion in the front-rear direction of the permanent magnet (36), and in the state where the movable member (8) is switched to the front end position, The sensor (35) is detached rearward from the permanent magnet (36). Therefore, the output of the sensor (35) varies depending on the position of the movable member (8), and the position of the movable member (8), that is, the ink calling roller (15), can be determined from the output of the sensor (35).

The ink in the ink fountain (42) passes through the ink passage (43) and exits to the outer peripheral surface of the ink fountain roller (41). The film thickness of the ink that appears on the surface of the ink fountain roller (41) corresponds to the size of the gap of the ink passage (43), and by adjusting the size of the gap of the ink passage (43), the ink fountain roller (41 The film thickness of the ink coming out on the surface is adjusted. Usually, the size of the gap of the ink passage (43) is adjusted so that the ink film thickness becomes equal for all the ink calling rollers (15). The ink that has appeared on the outer peripheral surface of the ink fountain roller (41) is transferred to the ink call roller (15) while the ink call roller (15) is switched to the front end position, and each ink call roller (15). The ink transferred to is transferred to the ink kneading roller (44) while the ink calling roller (15) is switched to the rear end position. Thus, ink kneading is performed to transfer ink from the ink fountain roller (41) to the ink kneading roller (44). The ink transferred to the ink kneading roller (44) is further supplied to the printing surface via a plurality of other ink kneading rollers (46) as shown in FIG. Also, the output of the sensor (35) detects whether or not the switching of the ink call roller (15) is normal, and if the ink call roller (15) is not switched normally, an alarm is issued. It is done.

  In the printing machine, the controller (34) calls the ink by switching the position of the required ink call roller (15) at each call timing with a predetermined interval, and for each ink call roller (15), Ink to be called from the ink fountain roller (41) to the ink call roller (15) by controlling the rotation angle (contact rotation angle) of the ink fountain roller (41) from contact with the ink fountain roller (41) until it leaves. As a result, the amount of ink supplied to the printing surface is adjusted by the position in the width direction.

  The contact rotation angle is controlled by the time from the output of the switching command (contact command) to the calling position to the ink calling roller (15) until the output of the switching command (non-contact command) to the non-calling position (contact command). Time).

  The control device (34) is provided with a command value of the ink amount corresponding to the pattern area for each ink calling roller as a graph value, and by raising the graph value of a predetermined ink calling roller, the ink calling roller The density of the ink call roller is decreased by increasing the density of the ink call roller and lowering the graph value of the predetermined ink call roller.

  When changing the plate, each graph value usually changes, but by giving a new command value, the concentration will eventually correspond to the command value. There was no control.

  In the control device of the ink supply apparatus of this embodiment, a control program for the density command value immediately after the plate replacement, which was not conventionally, is added. The main part of this program is shown in the flowchart of FIG.

  As shown in the flowchart of FIG. 4, when controlling the density command value immediately after the plate change, when performing the plate change without color change (S1), the pattern area before the plate change and the pattern area after the plate change When comparison is made for all ink call rollers (S2) and the pattern area increases after the plate is changed (S3), additional ink kneading (S4) is performed, and the pattern area decreases before the plate is changed In (S6), the operation of the ink calling roller is stopped for a certain time (S6).

  The ink held by the ink call roller at the time of stable printing is the ink with uniform thickness (Y) from the end of the ink call roller and the ink with the thickness proportional to the picture area of the printed material (proportional It is considered that the constant overlaps Y). Therefore, if the pattern area before the plate replacement is A%, the ink amount (%) held before the plate replacement is Y + AZ (%), and if the pattern area after the plate replacement is B%, after the plate replacement The retained ink amount (%) is Y + BZ (%). The difference before and after the plate exchange is (BA) Z (%).

  Since B> A and B <A, there are cases where the difference is a positive or negative value. Here, different operations are performed depending on whether the difference is positive or negative.

  First, in the case of difference (B−A) Z> 0, since the pattern area (required ink amount) after plate replacement is large, it indicates that ink is insufficient and additional ink kneading is necessary. For example, when the pattern area is changed from 30% to 40%, a command to set it to 40% is issued, so the actual ink amount is 30% + α, but the time until it reaches 40% It will be long. Therefore, additional ink kneading is performed by setting the number of ink kneading to a proportional number of Z times. The percentage of ink kneading is (BA) (%). As a result, in the conventional case, the concentration gradually increases and reaches a new command value concentration.On the other hand, after the concentration rapidly increases and reaches a value near the command value, the concentration of the command value is increased. And the printing density can be stabilized.

  On the other hand, when (B−A) Z <0, it indicates that ink is left. For example, when the pattern area is changed from 40% to 30%, a command to set it to 30% is issued, so the actual ink amount is 40% -α, but the time until it reaches 30%. Will be long. Therefore, the ink call is stopped for a predetermined period. The condition for stopping the ink call is that (A-B) Z / B ink calls are stopped. As a result, in the conventional case, the concentration gradually decreases and reaches the new command value concentration, whereas the concentration decrease amount greatly increases and reaches the command value concentration in a short time. The printing density can be stabilized.

  Thus, according to this ink supply apparatus, when replacing the plate, the pattern area before the plate replacement is A%, the retained ink amount (%) before the plate replacement is Y + AZ, the pattern area after the plate replacement is B%, and after the plate replacement If the retained ink amount (%) is Y + BZ and the difference (BA) before and after the plate change is positive or negative (BA) When Z> 0, Z additional ink kneading is performed. , (B−A) When Z <0, (A−B) Z / B ink calls are stopped so that the difference (B−A) when Z> 0 and (B−A) ) In any case where Z <0, the density of the command value after the plate change is reached in a short time, and the density of printing can be stabilized.

  When the amount of ink required for supplying the ink is small, an intermittent operation is performed in which the number of calls is reduced compared to the normal operation, instead of the normal operation in which the ink is called at each call timing.

  In intermittent operation, if the control contact length corresponding to the required ink amount is less than the minimum controllable contact length, the number of calls is reduced compared to the case where the ink is called every time at the call timing. The average value is controlled to be a control contact length corresponding to the required ink amount.

  In the intermittent operation, if B is equal to or less than the intermittent operation percentage and (BA) Z <0, it is preferable to stop the ink call for {(AB) Z / B} × C / B times. That is, if B is an intermittent operation percentage or less and (B−A) Z <0, it is not possible to sufficiently consume ink just by stopping (A−B) Z / B ink calls. Correspondingly, the number of times to stop the ink call is increased.

  By doing so, even if intermittent operation is performed, the density of the command value after plate replacement can be reached in a short time, and the density of printing can be stabilized.

  In the above, the configuration of the ink supply device of the printing press and the ink amount control method are not limited to those of the above-described embodiment, and can be changed as appropriate.

(1) Ink supply device for printing press
(2) Printing machine
(3) Ink supply device
(15) Ink call roller
(34) Control device
(41) Ink fountain roller
(42) Inkwell

Claims (2)

In the vicinity of the ink fountain roller constituting the ink fountain, a plurality of ink call rollers divided in the length direction of the ink fountain roller are arranged, and each ink call roller contacts the ink fountain roller and the ink fountain roller. It can be individually switched to a non-calling position that contacts the ink kneading roller away from the roller, and at each call timing at a predetermined interval, the ink is called by switching the position of the required ink call roller, and the ink fountain. Ink kneading is performed by transferring ink from the roller to the ink kneading roller, and by controlling the rotation angle of the ink fountain roller from contact with the ink fountain roller for each ink call roller, ink call from the ink fountain roller It is designed to control the circumference of the ink that is called to the roller. In the ink supply device of the printing machine,
When changing the plate, the pattern area before the plate change and the pattern area after the plate change are compared for all ink calling rollers.If the pattern area increases after the plate change, additional ink kneading is performed. If the pattern area decreases before plate replacement, the ink call roller stops operating for a certain period of time.
The pattern area before the plate change is A%, the ink amount (%) before the plate change is Y + AZ, the pattern area after the plate change is B%, and the ink amount (%) after the plate change is Y + BZ. An ink supply device for a printing press, wherein the following operation is performed in accordance with the positive / negative of the difference (B−A) Z (%).
(B-A) When Z> 0, Z additional kneading is performed.
(B−A) When Z <0, (A−B) Z / B ink calls are stopped.   A normal operation in which ink is called each time at each call timing and an intermittent operation in which the number of calls is smaller than that in the normal operation are performed. B is equal to or less than the intermittent operation percentage and (B−A) Z <0. The ink supply device of the printing press according to claim 1, wherein the ink call for {(A−B) Z / B} × C / B times is stopped.

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