Gravure offset printing machine

Abstract

To provide a gravure offset printer including a blanket dry unit which achieves high cooling efficiency of a blanket and is compact.SOLUTION: A gravure offset printer includes: a gravure plate fixing base configured to fix a gravure plate; a blanket cylinder 8 having a blanket 51; a printed object transport device to which a base material (an object to be printed) is fixed; and a blanket dry unit 35 facing a peripheral surface of the blanket 51 through a blanket surface adjustment space 52. The blanket dry unit 35 includes: a heating mechanism 53 configured to jet heating air (a heating gas) toward the blanket 51; and a cooling mechanism 55 configured to jet cooling air (a cooling gas) toward the blanket 51. The heating air and the cooling air pass through the blanket surface adjustment space 52.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a gravure offset printing press equipped with a blanket drying unit for drying a blanket. [Background technology]

[0002] In the field of printed electronics (PE), gravure offset printing machines are sometimes used, as described in Patent Document 1. When printing wiring on a printed circuit board, gravure offset printing is used when emphasis is placed on the precision of fine wiring.

[0003] A conventional gravure offset printing press may be equipped with a dryer for drying a blanket, as described in, for example, Patent Document 2. The blanket dryer disclosed in Patent Document 2 has a heating section which blows heated gas onto the surface of the blanket, and a cooling section which blows cooled gas onto the surface of the blanket. The heating section and the cooling section are arranged in a position facing the blanket while being aligned in the circumferential direction of the blanket cylinder. The heating section also has an exhaust port which forcibly exhausts the heated gas after being blown onto the blanket. The cooling section also has an exhaust port which forcibly exhausts the cooled gas after being blown onto the blanket.

[0004] In the heating section of the blanket dryer shown in Patent Document 2, heated gas is blown onto the blanket, and in the cooling section, cooled gas is blown onto the blanket by rotating the blanket body, thereby heating and cooling the blanket and drying the brackets. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-59077 [Patent Document 2] Japanese Patent Application Publication No. 4-59253 Summary of the Invention [Problem to be solved by the invention]

[0006] In conventional gravure offset printing machines, the blanket may absorb ink and become swollen as the printing process is repeated. When the blanket becomes swollen, the ink cannot be accepted by the blanket surface, making it difficult to form a fine wiring pattern, which may result in a loss of product quality.

[0007] The swollen blanket can be made capable of receiving ink again by increasing the temperature and drying it, as described in, for example, Patent Document 2. However, the blanket dryer described in Patent Document 2 has the following two problems. The first problem is the inefficiency of cooling the blanket after it has been dried.

[0008] In the blanket dryer shown in Patent Document 2, after the supply of heated gas to the heating section is stopped after drying is completed, heated gas remains in the heating section. The heating section is configured to suck out gas near the blanket from a forced exhaust port, but since this only promotes the evaporation of the solvent by lowering the air pressure, it is difficult to remove heat upstream of the flow path that guides the heated gas to the blanket. For this reason, the heat remaining in the heating section is transferred to the blanket, and cooling must be performed to that extent, resulting in poor cooling efficiency.

[0009] The second problem is that the blanket dryer becomes large because the heating section and the cooling section are arranged in the circumferential direction of the blanket cylinder.

[0010] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a gravure offset printing press equipped with a blanket drying unit which has high blanket cooling efficiency and is also compact. [Means for solving the problem]

[0011] In order to achieve this object, the gravure offset printing press of the present invention comprises a gravure plate fixing table for fixing a gravure plate, a blanket cylinder having a blanket that receives ink from recesses in the gravure plate, a printing substrate transport device to which a printing substrate is fixed, and a drying unit facing the peripheral surface of the blanket across a blanket surface adjustment space, the drying unit comprising a heating mechanism that sprays heated gas toward the blanket, and a cooling mechanism that sprays cooling gas toward the blanket, and both the heated gas emitted by the heating mechanism and the cooling gas emitted by the cooling mechanism pass through the blanket surface adjustment space.

[0012] The present invention, in the gravure offset printing machine, further includes a heating mechanism attaching / detaching means for moving the heating mechanism toward and away from the blanket, a heating operation end detection means for detecting the end of the heating operation by the heating mechanism, and a control device for controlling the operation of the heating mechanism attaching / detaching means, wherein the control device controls the operation of the heating mechanism attaching / detaching means so that the heating mechanism approaches the blanket when the heating mechanism performs a heating operation, and controls the operation of the heating mechanism attaching / detaching means so that the heating mechanism moves away from the blanket when the heating operation end detection means detects the end of the heating operation.

[0013] In the gravure offset printing machine of the present invention, the press may further include a blanket cylinder drive means capable of driving the blanket cylinder according to a plurality of predetermined drive patterns, and the control device may be configured to switch the drive pattern of the blanket cylinder drive means based on the detection result of the heating operation end detection means.

[0014] In the gravure offset printing machine of the present invention, the drive pattern when the heating mechanism performs a heating operation is a pattern in which the blanket cylinder rotates within a rotation range in which only an effective surface of the blanket cylinder faces the heating mechanism, The drive pattern when the cooling mechanism performs a cooling operation may be a pattern in which the blanket cylinder rotates in one direction so that the entire circumference of the blanket cylinder faces the cooling mechanism.

[0015] The gravure offset printing machine of the present invention may further include an exhaust duct that sucks in and exhausts the heating gas that has passed through the blanket surface conditioning space and flowed along the blanket. Effect of the Invention

[0016] In the present invention, since the cooling gas passes through the blanket surface conditioning space during cooling, the path through which the heat of the heating mechanism is transferred to the blanket is blocked by the cooling gas, so that the heat of the heating mechanism is not transferred to the blanket when the blanket is cooled, and a decrease in the cooling effect can be prevented. Furthermore, the heating mechanism and the cooling mechanism can be arranged compactly at the same position in the circumferential direction of the blanket cylinder. Therefore, according to the present invention, it is possible to provide a gravure offset printing press equipped with a blanket drying unit that has high blanket cooling efficiency and is compact. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a side view showing the configuration of a gravure offset printing apparatus according to the present invention. [Diagram 2] 2 is a plan view of a gravure offset printing machine, and a side view showing the configuration of a gravure offset printing apparatus. [Diagram 3] FIG. 3 is a cross-sectional view of the main part during heating. [Figure 4] FIG. 4 is a cross-sectional view of the main part during cooling. [Diagram 5] FIG. 5 is a side view illustrating the step of supplying ink. [Figure 6] FIG. 6 is a side view for explaining the process of receiving and transferring ink. [Figure 7] FIG. 7 is a cross-sectional view of a main part for explaining the heating operation. [Figure 8] FIG. 8 is a cross-sectional view of a main part for explaining the cooling operation. [Figure 9] FIG. 9 is a block diagram showing the configuration of the control system. [Figure 10] FIG. 10 is a side view showing the configuration of a gravure offset printing apparatus. [Figure 11] FIG. 11 is a side view showing the configuration of a gravure offset printing apparatus. [Figure 12] FIG. 12 is a cross-sectional view showing the configuration of a modified example of a gravure offset printing apparatus. [Figure 13] FIG. 13 is a cross-sectional view for explaining the operation of the gravure offset printing apparatus. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, one embodiment of a gravure offset printing press according to the present invention will be described in detail with reference to Figs. The gravure offset printing press 1 shown in Fig. 1 includes a printing unit 3 provided in the center of a base 2 depicted at the bottom in Fig. 1, an ink supply unit 4 located to the left of the printing unit 3 in Fig. 1, and a substrate holding unit 5 located on the opposite side of the printing unit 3 to the ink supply unit 4. In this gravure offset printing press 1, ink 7 (see Fig. 5) supplied to a gravure plate 6 (described later) in the ink supply unit 4 moves to a blanket cylinder 8 (described later) of the printing unit 3, and further moves from the blanket cylinder 8 to a substrate 9 as a printing target in the substrate holding unit 5. In the following, the movement of the ink 7 from the ink supply unit 4 to the blanket cylinder 8 is referred to as "receiving", and the movement of the ink 7 from the blanket cylinder 8 to the substrate 9 is referred to as "transfer".

[0019] (Explanation of the ink supply section) Ink 7 is a conductive paste containing a metallic substance, a flux paste, a resist, or the like, and is applied to gravure plate 6 from ink supply device 11 (see FIG. 5) serving as an ink supply means provided above ink supply unit 4. The gravure plate 6 is an intaglio plate having a printing pattern portion 12 consisting of recesses 6a, and is detachably fixed to a gravure plate fixing stand 13. The gravure plate fixing stand 13 is movably supported by rails 14 provided on an apparatus installation surface 2a consisting of the upper surface of the base 2. The rails 14 extend horizontally on the base 2 from one end to the other end of the base 2. The extension direction of the rails 14 is horizontal and perpendicular to the axis of a blanket cylinder 8 described below.

[0020] The gravure plate fixing table 13 is connected to a gravure plate fixing table drive device 15 (see FIG. 9), and is driven by the gravure plate fixing table drive device 15 to move parallel along the rails 14. The operation of the gravure plate fixing table drive device 15 is controlled by a control device 16, which will be described later. The ink supply device 11 is configured to eject ink 7 downward, and is installed above the rail 14. Although not shown in detail, this ink supply device 11 can be realized by using, for example, a nozzle for applying ink, an inkjet head, or the like.

[0021] The operation of the ink supply device 11 is controlled by a control device 16, which will be described later. A blade 17 and a doctor 18 are provided near the ink supply device 11 as ink pushing means. The blade 17 is disposed at a position closer to the blanket cylinder 8 than the ink supply device 11, and the doctor 18 is disposed at a position farther from the blanket cylinder 8 than the ink supply device 11. The blade 17 and the doctor 18 are supported by lifting devices 19, 20, respectively (see FIG. 9), and are driven by the lifting devices 19, 20 to lift and lower independently. The operation of the blade lifting device 19 and the doctor lifting device 20 is controlled by the control device 16.

[0022] (Description of the substrate holder) The substrate holding unit 5 is equipped with a printing substrate fixing table 21 that detachably supports the substrate 9. The printing substrate fixing table 21 is supported on the rails 14 so as to be freely movable. The printing substrate fixing table 21 is also connected to a substrate fixing table drive device 22 (see FIG. 9), and is driven by the substrate fixing table drive device 22 to move in parallel along the rails 14. The operation of the substrate fixing table drive device 22 is controlled by a control device 16, which will be described later. In this embodiment, the printing substrate fixing table 21 and the substrate fixing table drive device 22 correspond to the "printing substrate transport device" of the present invention.

[0023] (Explanation of the printing section) The printing section 3 comprises a first frame 31 fixed to the equipment installation surface 2a of the base 2, a second frame 33 supported on the first frame 31 via a frame lifting device 32 (see Figures 3 and 9), a blanket cylinder 8 rotatably supported on the second frame 33, a blanket cylinder drive device 34 (see Figure 9) as a blanket cylinder drive means for driving the blanket cylinder 8, and a blanket drying unit 35 arranged on the second frame 33 adjacent to the blanket cylinder 8.

[0024] As shown in FIG. 2, the first frames 31 are provided on one side and the other side of the base 2, and are fixed to the base 2 so as not to move relative to the base 2. The frame lifting device 32 includes a first guide rail 36 provided on each of the two first frames 31, and a first actuator 37 (see Figure 9) that raises and lowers the second frame 33 along the first guide rails 36. The first guide rail 36 is formed to extend in the vertical direction, and supports the second frame 33 movably so that the movement direction is only in the vertical direction. The first actuator 37 is provided for each first frame 31. The operation of the first actuator 37 is controlled by the control device 16.

[0025] 2, the second frame 33 is provided on each of the two first frames 31, and includes a heating mechanism attaching / detaching device 42 (see FIG. 9) as a heating mechanism attaching / detaching means for driving a housing 41 (see FIG. 3) of a blanket drying unit 35 described later. The heating mechanism attaching / detaching device 42 includes a second guide rail 43 (see FIG. 3) provided on each of the two second frames 33, and a second actuator 44 (see FIG. 9) for moving the housing 41 of the blanket drying unit 35 in parallel along the second guide rail 43.

[0026] 3, the second guide rails 43 are formed to extend in the radial direction of the blanket cylinder 8 and diagonally upward when viewed from the axial direction of the blanket cylinder 8, and support a housing 41 of a blanket drying unit 35 described below so that the housing 41 can move in parallel. A second actuator 44 is provided for each second guide rail 43. The second actuator 44 moves the housing 41 in parallel along the second guide rails 43, causing the housing 41 to advance and retreat relative to the blanket cylinder 8.

[0027] As shown in Figure 2, the blanket cylinder 8 is installed extending in a direction perpendicular to the rail 14 when viewed from above, with one axial end being rotatably supported by one of the second frames 33, and the other axial end being rotatably supported by the other second frame 33. As shown in Fig. 3, the blanket cylinder 8 according to this embodiment has a cutout 45 having a structure in which part of the outer periphery is partially recessed, and an effective surface 46 consisting of a peripheral surface formed on the remaining part of the outer periphery. The cutout 45 is formed so as to extend from one end to the other end in the axial direction of the blanket cylinder 8. A pair of clamp mechanisms 47 are provided in this cutout 45. These clamp mechanisms 47 hold one end and the other end of a blanket 51 wrapped around the effective surface 46 of the blanket cylinder 8 in a tensioned state.

[0028] The blanket 51 receives the ink 7 from the recesses 6a of the gravure plate 6 and transfers it to the substrate 9, and is formed, for example, in a sheet shape from silicone rubber and wrapped around the effective surface 46 of the blanket cylinder 8. Although not shown, the blanket cylinder 8 may be formed in a cylindrical shape without the cutout 45. In this case, one end and the other end of the blanket 51 are each attached to the peripheral surface of the blanket cylinder 8 with adhesive tape.

[0029] The blanket cylinder drive device 34 is supported by one of the second frames 33 and has a structure for driving one axial end of the blanket cylinder 8. The operation of the blanket cylinder drive device 34 is controlled by the control device 16. The blanket cylinder drive device 34 according to this embodiment is controlled by the control device 16 to rotate the blanket cylinder 8 at a predetermined rotation angle and in one direction. In other words, the blanket cylinder drive device 34 is capable of driving the blanket cylinder 8 according to a plurality of predetermined drive patterns.

[0030] (Explanation of the drying unit) The blanket drying unit 35 is disposed near the blanket cylinder 8, obliquely above the horizontal direction from the blanket cylinder 8 toward the substrate holding unit 5. The blanket drying unit 35 is formed to extend from one end to the other end in the axial direction of the blanket cylinder 8, and faces the circumferential surface of the blanket 51 wound around the blanket cylinder 8 across a blanket surface conditioning space 52. The blanket surface conditioning space 52 is a space formed between the blanket 51 and the blanket drying unit 35, and is open to the atmosphere except for the portion sandwiched between the blanket drying unit 35 and the blanket cylinder 8.

[0031] The blanket drying unit 35 includes a heating mechanism 53 including the housing 41 described above, and a cooling mechanism 55 having a cooling nozzle 54 provided in the vicinity of the housing 41 . The heating mechanism 53 is for heating and drying the blanket 51, and is configured by assembling components in the housing 41. The housing 41 is formed in a box shape that opens toward the blanket cylinder 8, and is driven by a second actuator 44 to reciprocate between a heating position shown in FIG. 3 and a cooling position shown in FIG.

[0032] 3, the housing 41 according to this embodiment approaches the blanket cylinder 8 so as to create a predetermined gap between the blanket 51 and the housing 41. In this embodiment, as the housing 41 moves to the heating position, a part of the blanket cylinder 8 enters between the upper end and the lower end of the housing 41. The components of heating mechanism 53 according to this embodiment include a heater 56 provided inside housing 41, a heating nozzle 57, and an air passage 58. The distance between the heating position and the cooling position of housing 41 can be set to about 20 mm to 40 mm.

[0033] The heater 56 generates heat when electricity is applied. The heater 56 in this embodiment is configured to be powered by the control device 16 via a thermostat 59 (see FIG. 9). The thermostat 59 is configured to power the heater 56 to increase the temperature when the temperature of the heater 56 is lower than a predetermined minimum temperature, and to cut off power to the heater 56 when the temperature of the heater 56 reaches a predetermined maximum temperature. The maximum temperature is a temperature at which the amount of heat required for heating, which will be described later, can be obtained. For this reason, the heater 56 is maintained at a temperature between the minimum temperature and the maximum temperature, and the heating mechanism 53 can start a heating operation, which will be described later, when the heater 56 has been heated to a predetermined temperature.

[0034] (Explanation of heating mechanism) The time to stop the heating operation by heating mechanism 53 is detected by heating operation end detection means 61 connected to control device 16. The heating operation end detection means 61 can be configured by a timer that detects when the elapsed time from the start of heating reaches a predetermined heating time and sets this time as the end of the heating operation, or a temperature sensor that detects when the temperature of blanket 51 or the vicinity of blanket 51 reaches a predetermined heating end temperature and sets this time as the end of the heating operation, or the like.

[0035] The heating nozzle 57 blows out air supplied from an air supply pipe (not shown), and is disposed so as to blow the air toward an air passage 58 in the housing 41. A heating air supply valve 62 (see FIG. 9) is provided in the air supply passage including the air supply pipe. The operation of the heating air supply valve 62 is controlled by the control device 16 to open and close. When the heating air supply valve 62 is closed, the supply of air to the heating nozzle 57 is cut off, and when the heating air supply valve 62 is opened, air is supplied to the heating nozzle 57. The amount of air supplied to the heating nozzle 57 can be increased or decreased, and is set according to the state of the blanket 51, the size of the ink receiving area, etc.

[0036] In addition, although not shown, the heating nozzles 57 are provided at multiple positions spaced at predetermined intervals in the longitudinal direction of the housing 41 (axial direction of the blanket cylinder 8), and are configured to blow air over the entire longitudinal area of ​​the housing 41 at one end (upstream end) of the air passage 58 within the housing 41. In this embodiment, air passage 58 is formed integrally with housing 41 by a member that constitutes housing 41, and extends from heating nozzle 57 through the vicinity of heater 56 to an opening of housing 41. Air blown out from heating nozzle 57 is heated by contacting heater 56, and becomes heated air, which is referred to as heated gas in the present invention, and is ejected from downstream end 58a of air passage 58. In Figure 3, the direction in which air flows in air passage 58 is indicated by an arrow.

[0037] The air passage 58 is also formed so as to extend from the heating nozzle 57 to the opening of the housing 41 over the entire longitudinal area of ​​the housing 41. As shown in Fig. 3, the downstream end 58a of the air passage 58 is formed at the lower end of the housing 41 located diagonally above the blanket cylinder 8. For this reason, the heated air is ejected from the entire longitudinal area of ​​the housing 41 at the lower end of the housing 41, and is blown onto the blanket 51 through the blanket surface adjusting space 52.

[0038] An exhaust duct 63 is connected to the upper end of the housing 41. The exhaust duct 63 opens into the upper end of the housing 41, and receives negative pressure from an exhaust device (not shown), sucking in and discharging the heated air after heating the blanket 51. As shown in FIG. 2, the exhaust ducts 63 are provided at a plurality of positions spaced apart at predetermined intervals in the longitudinal direction of the housing 41 (the axial direction of the blanket cylinder 8).

[0039] An exhaust valve 64 (see FIG. 9) is provided in the exhaust passage leading to the exhaust duct 63. The operation of the exhaust valve 64 is controlled by the control device 16 to open and close. When the exhaust valve 64 opens, the heated air in the housing 41 is sucked into the exhaust duct 63, and when the exhaust valve 64 closes, the suction of the heated air stops. In this embodiment, the amount of air exhausted from the exhaust duct 63 is set to be equal to the amount of air supplied from the heating nozzle 57.

[0040] The exhaust valve 64 closes when the gravure offset printing press 1 is performing a printing operation, and opens when the blanket drying unit 35 is operating (when the heating mechanism 53 is operating and when the cooling mechanism 55 is operating). Therefore, air is always sucked in from the exhaust duct 63 except when the printing operation is being performed. The exhaust duct 63 and the above-mentioned air supply pipe have a flexible pipe structure (not shown) to allow the heating mechanism 53 to move along the second guide rail 43.

[0041] (Explanation of the cooling mechanism) The cooling mechanism 55 cools the blanket 51, the temperature of which has risen due to the operation of the heating mechanism 53, by air cooling. The cooling mechanism 55 includes a cooling nozzle 54 for air cooling the blanket 51. The cooling nozzle 54 blows air supplied from a cooling air supply pipe (not shown), and is disposed near the opening of the housing 41, near the lower side and the upper side of the housing 41 at the heating position. Hereinafter, the air blown out from the cooling nozzle 54 is referred to as "cooling air". In this embodiment, the cooling air corresponds to the "cooling gas" of the present invention. The cooling nozzle 54 is supported by the second frame 33 by a bracket (not shown) so that the cooling air is blown out in a direction toward the blanket cylinder 8.

[0042] Furthermore, the cooling nozzles 54 are provided at a plurality of positions spaced apart at predetermined intervals in the longitudinal direction of the housing 41. The cooling air may be air at room temperature or a gas such as nitrogen gas. A cooling air supply valve 65 (see FIG. 9) is provided in the passage for supplying air to the cooling nozzle 54. The operation of the cooling air supply valve 65 is controlled by the control device 16 to open and close. When the cooling air supply valve 65 is closed, the supply of air to the cooling nozzle 54 is cut off, and when the cooling air supply valve 65 is opened, cooling air is ejected from the cooling nozzle 54. The amount of cooling air can be increased or decreased. In order to improve the cooling efficiency, it is effective to increase the amount of cooling air. The amount of cooling air can be made greater than the amount of heated air.

[0043] As shown in Fig. 3, when the housing 41 is in the heating position, even if cooling air is ejected from the cooling nozzle 54, it is blocked by the housing 41. However, as shown in Fig. 4, when the housing 41 moves to the cooling position, the cooling air ejected from the cooling nozzle 54 passes through the blanket surface adjusting space 52 and is blown onto the blanket cylinder 8. In Fig. 4, the direction in which the cooling air flows is indicated by an arrow. In this blanket drying unit 35, heated air passes through the blanket surface adjusting space 52 during heating when the heating mechanism 53 operates, and cooled air passes through the blanket surface adjusting space 52 during cooling when the cooling mechanism 55 operates. That is, both the heated air (heated gas) generated by the heating mechanism 53 and the cooled air (gas for cooling) generated by the cooling mechanism 55 pass through the blanket surface adjusting space 52.

[0044] The time to stop the cooling operation by the cooling mechanism 55 is detected by a cooling operation end detection means 66 connected to the control device 16. The cooling operation end detection means 66 can be configured by a timer that detects when the elapsed time from the start of cooling reaches a predetermined cooling time and sets this time as the end time of the cooling operation, or a temperature sensor that detects when the temperature of the blanket 51 or the vicinity of the blanket 51 reaches a predetermined cooling end temperature and sets this time as the end time of the cooling operation, or the like.

[0045] (Description of the control device) As shown in Figure 9, the control device 16 has a printing operation control unit 71 and a drying unit control unit 72, and is connected to a printing start switch 73, a drying start time setting means 74, a heating operation end detection means 61, and a cooling operation end detection means 66 on its input side, and is connected to various driving devices, etc., and controls all operations of the gravure offset printing press 1. The printing operation control unit 71 controls the operations of the ink supply unit 4, the substrate holding unit 5, and the printing unit 3 so that printing is performed by the gravure offset printing machine 1.

[0046] The drying unit control unit 72 controls the operations of the heating mechanism attaching / detaching device 42, the heating mechanism 53, and the cooling mechanism 55 so that the blanket 51 is dried in the blanket drying unit 35. The print start switch 73 can be configured, for example, as a switch that is manually operated. When the print start switch 73 is turned on, the control device 16 starts the printing operation. The drying start time setting means 74 is for setting the time when the blanket drying unit 35 starts the drying operation. The time when the drying operation starts can be set so that the drying operation is performed every time one printing operation is completed, or after a predetermined number of printing operations are completed, or at any time. Furthermore, the drying start time setting means 74 first makes the heating mechanism 53 start the heating operation when the blanket drying unit 35 starts the drying operation, and makes the cooling mechanism 55 start the cooling operation after the heating operation by the heating mechanism 53 is completed.

[0047] (Explanation of the operation of a gravure offset printing machine) Next, the printing operation and drying operation of the gravure offset printing press 1 according to this embodiment will be described with reference to FIGS. In the gravure offset printing machine 1 according to this embodiment, the printing operation is started by turning on the print start switch 73. When the printing operation is started, first, the ink supply unit 4 fills the print pattern portion 12 formed on the gravure plate 6 with ink 7. The method of filling the ink 7 is as follows: first, as shown in Fig. 5(A), ink supply device 11 (nozzle, inkjet head, etc.) supplies ink 7 onto the gravure plate 6.

[0048] 5(B)-(C), blade 17 is lowered, and in this state, gravure plate fixing base drive device 15 moves gravure plate fixing base 13 in a direction approaching blanket cylinder 8, thereby forcing ink 7 into recesses 6a (print pattern portion 12) of gravure plate 6. Finally, blade 17 is raised and doctor blade 18 is lowered, and in this state, as shown in Fig. 5(D), gravure plate fixing base drive device 15 moves gravure plate fixing base 13 in a direction away from blanket cylinder 8, thereby scraping off excess ink 7 protruding from recesses 6a.

[0049] After the printing pattern section 12 has been filled with ink 7 in this manner, the doctor blade 18 is raised, and the gravure plate fixing table drive device 15 moves the gravure plate fixing table 13 in a direction approaching the blanket cylinder 8. At this time, the second frame 33 is lowered by the frame lifting device 32 in the printing section 3. Then, as shown in Figure 6 (A), in this state, the gravure plate fixing table 13 is moved toward the blanket cylinder 8, and the blanket 51 is brought into contact with the printing pattern section 12 of the gravure plate 6, causing the blanket cylinder 8 to rotate so as to follow the movement of the gravure plate 6.

[0050] As the gravure plate 6 passes under the blanket cylinder 8, the ink 7 is received on the surface of the blanket 51. Thereafter, the second frame 33 is raised and, with the blanket cylinder 8 moving upward, the gravure plate fixing base 13 is moved back to its initial position, and after the gravure plate fixing base 13 has passed, the second frame 33 is lowered. Then, as shown in FIG. 6(B), the printing substrate fixing base 21 is moved in a direction approaching the blanket cylinder 8, and the blanket 51 is brought into contact with the substrate 9, and the blanket cylinder 8 is rotated to follow the movement of the substrate 9. As the substrate 9 passes under the blanket cylinder 8, the ink 7 on the blanket 51 is transferred to the substrate 9.

[0051] After the ink 7 has been transferred to the substrate 9, the second frame 33 is raised to move the blanket cylinder 8 upward, and the printing substrate fixing table 21 is returned to its initial position, thereby completing the printing operation. After the printing operation is thus completed, the control device 16 performs the drying operation at the time set in the drying start time setting means 74. The control device 16 energizes the thermostat 59 in advance before performing the drying operation.

[0052] In performing the drying operation, first, the control device 16 controls the blanket cylinder drive device 34 to position the blanket cylinder 8 at the drying start position. The drying start position is a position where the cutout 45 of the blanket cylinder 8 does not face the heating mechanism 53, and where one end of the effective surface 46 of the blanket cylinder 8 (the end adjacent to the cutout 45) faces the downstream end 58a of the air passage 58, as shown in Figures 3 and 7(A).

[0053] Next, the control device 16 moves the heating mechanism 53 (housing 41) to the heating position, and opens the heating air supply valve 62 and the exhaust valve 64. At this time, the air coming out of the heating nozzle 57 comes into contact with the heater 56 and flows to become heated air, which is then blown onto the blanket 51 from the downstream end 58a of the air passage 58 through the blanket surface adjustment space 52. The blanket 51 is heated by the heated air being blown onto it, and the ink or liquid components contained in the ink that have been attached to or absorbed by the blanket 51 evaporate. The heated air blown onto the blanket 51 is sucked into the exhaust duct 63 and exhausted from within the housing 41.

[0054] With the heated air being blown onto the blanket 51 in this manner, the control device 16 controls the blanket cylinder drive device 34 to rotate the blanket cylinder 8 in a predetermined direction. The rotation direction at this time is a direction in which the other end of the effective surface 46 approaches the downstream end 58a of the air passage 58 while maintaining the state in which the blanket 51 faces the downstream end 58a of the air passage 58, as shown in Figs. 7(B) to (C). After the other end of the effective surface 46 faces the downstream end 58a of the air passage 58, the control device 16 reverses the blanket cylinder 8 so that one end of the effective surface 46 faces the downstream end 58a of the air passage 58. In other words, the control device 16 rotates the blanket cylinder 8 so that the heated air is not blown onto the cutout portion 45 of the blanket cylinder 8, and only the effective surface 46 of the blanket cylinder 8 faces the downstream end 58a of the air passage 58.

[0055] The heating operation performed by rotating the blanket cylinder 8 in this manner continues until the heating end time is detected by the heating operation end detection means 61. If the ink 7 is concentrated in one part of the blanket 51, the rotation angle of the blanket cylinder 8 can be changed so that only the ink receiving area on the blanket surface is heated. After the heating end time is reached, as shown in Fig. 8(A), controller 16 moves heating mechanism 53 (housing 41) to the cooling position and closes heating air supply valve 62. Then, as shown in Figs. 8(B) to (C), controller 16 opens cooling air supply valve 65 to eject cooling air from cooling nozzle 54, and controls blanket cylinder drive device 34 to rotate blanket cylinder 8.

[0056] At this time, the control device 16 rotates the blanket cylinder 8 in only one direction. As a result, the cooling air ejected from the cooling nozzle 54 is blown not only onto the blanket 51 but also onto the cutout portion 45 of the blanket cylinder 8 and the clamp mechanism 47, improving the cooling efficiency. As the cooling air is ejected from the cooling nozzle 54, the heat transfer path between the heating mechanism 53 and the blanket 51 is blocked by the cooling air, so that even though the heater 56 of the heating mechanism 53 is generating heat, the blanket 51 can be cooled by air cooling without being affected by this heat.

[0057] The cooling operation performed by ejecting cooling air from the cooling nozzle 54 continues until the cooling operation end detection means 66 detects the cooling end time. When the cooling end time is reached, the control device 16 closes the cooling air supply valve 65 and closes the exhaust valve 64. At this time, the control device 16 does not change the control content of the second actuator 44, and holds the housing 41 of the heating mechanism 53 in the cooling position. Therefore, the drying operation of the blanket 51 by the blanket drying unit 35 ends with the housing 41 in the cooling position and the ejection of the heated air and the cooling air stopped. The heater 56 is maintained at a predetermined temperature by the thermostat 59 even after the drying operation ends.

[0058] In the gravure offset printing press 1 configured in this manner, cooling air (gas for cooling) passes through the blanket surface adjustment space 52 when cooling the blanket 51, and the path along which heat from the heating mechanism 53 is transferred to the blanket 51 during cooling is blocked by the cooling air. Therefore, when cooling the blanket 51, the heat from the heating mechanism 53 is not transferred to the blanket 51, and a decrease in the cooling effect can be prevented. Furthermore, according to this embodiment, the heating mechanism 53 and the cooling mechanism 55 can be arranged compactly at the same position in the circumferential direction of the blanket cylinder 8. Therefore, according to this embodiment, it is possible to provide a gravure offset printing press having a blanket drying unit that has high blanket cooling efficiency and is compact.

[0059] The miniaturization of the blanket drying unit 35 increases the free space around the blanket cylinder 8. As a result, the workability of replacing the blanket 51 is improved. In addition, it becomes easy to secure space for installing other devices near the periphery of the blanket cylinder 8, such as a bracket cleaner, a static eliminator, a camera, a sensor, etc., although not shown.

[0060] The gravure offset printing press 1 according to this embodiment includes a heating mechanism attaching / detaching device 42 that moves the heating mechanism 53 toward and away from the blanket 51, a heating operation end detection means 61 that detects when the heating operation by the heating mechanism 53 has ended, and a control device 16 that controls the operation of the heating mechanism attaching / detaching device 42. When the heating mechanism 53 is performing a heating operation, the control device 16 controls the operation of the heating mechanism attaching / detaching device 42 so that the heating mechanism 53 approaches the blanket 51, and when the heating operation end detection means 61 detects the end of the heating operation, the control device 16 controls the operation of the heating mechanism attaching / detaching device 42 so that the heating mechanism 53 moves away from the blanket 51.

[0061] Therefore, during the heating operation, it becomes possible to directly blow heated air onto the blanket 51. In addition, since the heating mechanism 53 moves away from the blanket 51 after the heating operation is completed, the heat of the heater 56 and the residual heat of the heating mechanism 53 are less likely to be transmitted to the blanket 51 during cooling. Therefore, the heating and cooling of the blanket 51 can be performed more efficiently.

[0062] The gravure offset printing press 1 according to this embodiment is equipped with a blanket cylinder drive device 34 capable of driving the blanket cylinder 8 according to a number of predetermined drive patterns. The control device 16 is configured to switch the drive pattern of the blanket cylinder drive device 34 based on the detection result of the heating operation end detection means 61. This makes it possible to operate the blanket cylinder 8 in an optimal manner when heating and cooling the blanket 51, respectively, thereby improving both the heating efficiency and the cooling efficiency.

[0063] In this embodiment, the drive pattern of blanket cylinder drive device 34 when heating mechanism 53 performs a heating operation is a pattern in which blanket cylinder 8 rotates so that only effective surface 46 of blanket cylinder 8 faces heating mechanism 53. The drive pattern of blanket cylinder drive device 34 when cooling mechanism 55 performs a cooling operation is a pattern in which blanket cylinder 8 rotates in one direction so that the entire circumference of blanket cylinder 8 faces cooling mechanism 55. For this reason, during heating, heated air is blown only onto the blanket 51, and is unlikely to be blown onto the cutouts 45 of the blanket cylinder 8 or the clamp mechanism 47. During cooling, cooled air is blown onto the entire blanket cylinder 8, including the blanket 51, to cool the entire blanket cylinder 8. This makes it possible to further increase the heating efficiency and cooling efficiency.

[0064] The gravure offset printing press 1 according to this embodiment is provided with an exhaust duct 63 that sucks in and exhausts the heated air (gas for heating) that has passed through the blanket surface conditioning space 52 and flowed along the blanket 51. This makes it possible to prevent the heated air from coming into contact with the members around the blanket drying unit 35 and causing the temperature around the blanket cylinder 8 to rise.

[0065] In the above-described embodiment, an example has been shown in which the air passage 58 having the heater 56 of the heating mechanism 53 is formed by the material constituting the housing 41. However, in the heating mechanism 53, a heat insulating material (not shown) can be provided around the heater 56 to prevent the heat of the heater 56 from being transferred to the blanket 51 side.

[0066] In the above-described embodiment, an example has been shown in which the heating nozzle 57 is provided inside the housing 41. However, although not shown, the heating nozzle 57 can be disposed outside the housing 41. In this case, an air vent is formed in the housing 41 at a position opposite the heating nozzle 57, and the air blown out from the heating nozzle 57 passes through the air vent and the downstream end 58a of the air passage 58 toward the blanket 51. By adopting this configuration, the hot air inside the housing 41 is sucked out by the air supplied from the air vent, passes through the blanket surface conditioning space 52, and is blown onto the blanket 51.

[0067] Furthermore, the above-mentioned heating mechanism 53 is configured to generate heated air by heating air with the built-in heater 56. However, the heated air can be generated outside the blanket drying unit 35 and supplied to the heating nozzle 57. In this case, the heating nozzle 57 may be disposed so as to face the blanket 51, and the heated air may be blown directly from the heating nozzle 57 onto the blanket 51.

[0068] The gravure plate fixing base 13 shown in the embodiment described above is formed in a flat plate shape in order to support the flat gravure plate 6. However, the gravure plate fixing base can be configured, for example, as shown in Figures 10 and 11. In Figures 10 and 11, members that are the same as or equivalent to those described in Figures 1 to 9 are given the same reference numerals and detailed descriptions thereof will be omitted as appropriate.

[0069] 10 and 11 rotatably supports a cylindrical gravure plate 82. The gravure plate 82 is an intaglio plate having a printing pattern portion 83 consisting of recesses 82a, and is rotatably supported by the gravure plate fixing base 81 with its axis parallel to the axis of the blanket cylinder 8. The gravure plate 82 is connected to a rotation drive device (not shown) and rotates. As the gravure plate 82 rotates in contact with the blanket cylinder 8, ink is received by the blanket cylinder 8. Even when the gravure plate fixing table 81 is configured in this manner, it is possible to provide a gravure offset printing press having a compact blanket drying unit with high blanket cooling efficiency.

[0070] The gravure offset printing machine 1 according to the embodiment described above employs a printing method in which the gravure plate fixing table 13, 81 and the printing material fixing table 21 move relative to the blanket cylinder 8 to receive and transfer the ink 7. However, as long as the blanket 51 can receive the ink 7 applied to the gravure plate 6, 82 in a printing pattern and transfer it to the substrate 9, the printing method is not limited to the printing method according to this embodiment and can be changed as appropriate. For example, as shown in Fig. 12 and Figs. 13(A) and (B), a printing configuration in which ink is transferred from a movable blanket cylinder to a roll-shaped substrate can be adopted. In Fig. 12 and Figs. 13(A) and (B), the same reference numerals are used for members that are the same or equivalent to those described in Figs. 1 to 9, and detailed description thereof will be omitted as appropriate.

[0071] A gravure offset printing machine 91 shown in FIG. 12 includes a printing substrate transport device 93 that uses a web-like substrate 92 wound in a roll as a printing substrate. The printing substrate transport device 93 includes a feed shaft 94 around which the substrate 92 is wound, a recovery shaft 95 around which the tip end of the substrate 92 is wound, and a plurality of rollers 96-99 that define a movement path of the substrate 92. The movement path of the substrate 92 is set so that the substrate 92 passes over a stage 101 of the base 2. In the printing substrate transport device 93, the recovery shaft 95 rotates, whereby the substrate 92 is pulled out from the feed shaft 94, moves over the stage 101, and is wound up on the recovery shaft 95.

[0072] The blanket cylinder 8 of this gravure offset printing press 91 is movably supported on rails 102 provided on the base 2, and is driven by a driving device (not shown) to move between the gravure plate fixing base 13 and the stage 101. The gravure plate fixing base 13 in this embodiment is fixed to the base 2.

[0073] In the gravure offset printing press 91 according to this embodiment, in order to have the blanket cylinder 8 receive the ink from the gravure plate 6, as shown in Fig. 13(A), the blanket cylinder 8 is moved horizontally and rotated while in contact with the gravure plate 6 from above. In addition, in order to transfer the ink from the blanket cylinder 8 to the substrate 92, as shown in Fig. 13(B), the blanket cylinder 8 is moved above the substrate 92, which is fixed to the stage 101, and in this state, the blanket cylinder 8 is moved horizontally and rotated while in contact with the substrate 92 from above. Even when the configuration shown in FIG. 12 and FIGS. 13(A) and (B) is adopted, it is possible to provide a gravure offset printing press having a compact blanket drying unit with high blanket cooling efficiency. [Explanation of symbols]

[0074] 1,91...gravure offset printing machine, 6...gravure plate, 7...ink, 8...blanket cylinder, 13...gravure plate fixing table, 16...control device, 21...printed material fixing table, 22...substrate fixing table drive device, 34...blanket cylinder drive device, 35...blanket drying unit, 42...heating mechanism attachment / detachment device, 46...effective surface, 51...blanket, 52...blanket surface adjustment space, 53...heating mechanism, 55...cooling mechanism, 61...heating operation end detection means, 63...exhaust duct, 93...printed material transport device.

Claims

1. a gravure plate fixing stand for fixing the gravure plate; a blanket cylinder having a blanket for receiving ink from the recesses of the gravure plate; A printing substrate transport device to which a printing substrate is fixed; a drying unit facing the circumferential surface of the blanket across a blanket surface conditioning space; The drying unit comprises: a heating mechanism that ejects heated gas toward the blanket; a cooling mechanism for ejecting a cooling gas toward the blanket; The heated gas generated by the heating mechanism and the cooling gas generated by the cooling mechanism both pass through the blanket surface conditioning space, The gravure offset printing press, characterized in that the cooling mechanism is provided with a cooling nozzle that blows the cooling gas onto the blanket through a gap between the blanket and the heating mechanism in the blanket surface conditioning space.

2. 2. The gravure offset printing machine according to claim 1, moreover, a heating mechanism attaching / detaching means for moving the heating mechanism forward and backward relative to the blanket; a heating operation end detection means for detecting that a heating operation by the heating mechanism has ended; A control device for controlling the operation of the heating mechanism attaching / detaching means, The control device includes: When the heating mechanism performs a heating operation, the operation of the heating mechanism attaching / detaching means is controlled so that the heating mechanism approaches the blanket; a heating mechanism attaching / detaching means for controlling an operation of the heating mechanism attaching / detaching means so that the heating mechanism is moved away from the blanket when the heating operation end detection means detects the end of the heating operation.

3. 3. The gravure offset printing machine according to claim 2, The blanket cylinder driving means is capable of driving the blanket cylinder according to a plurality of predetermined driving patterns, The gravure offset printing machine, wherein the control device is configured to switch the drive pattern of the blanket cylinder drive means based on a detection result of the heating operation end detection means.

4. 4. The gravure offset printing machine according to claim 3, the drive pattern when the heating mechanism performs a heating operation is a pattern in which the blanket cylinder rotates so that only an effective surface of the blanket cylinder faces the heating mechanism, A gravure offset printing press, characterized in that when the cooling mechanism performs a cooling operation, the drive pattern is a pattern in which the blanket cylinder rotates in one direction so that the entire circumference of the blanket cylinder faces the cooling mechanism.

5. 2. The gravure offset printing machine according to claim 1, The gravure offset printing press further comprises an exhaust duct for sucking in and discharging the heating gas that has passed through the blanket surface conditioning space and flowed along the blanket.

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