Printing pressure adjusting apparatus of printing cylinders

Abstract: When a screw 60 has been adjusted, a printing pressure adjusting disc 72 is turned through a shaft 75 and a segment gear 73 to adjust an eccentric pin through a link 78 and a lever 79. Also when the amount of eccentricity of a rubber cylinder 53 has been changed as a result of the adjustment of the stopper screw 60, the eccentric pin of each plate cylinder also is simultaneously adjusted in accordance with the amount of adjustment of the screw 60, and further the amount of eccentricity of the plate cylinder is changed to such a state that a printing pressure is kept constant in relation to the rubber cylinder 53, thus enabling the printing pressure adjustment with little labor and time to thereby improve printing operation performance.

Description: BACKGROUND OF THE INVENTION [Field of the Utilization] The present invention relates to a printing pressure adjusting apparatus which adjusts the printing pressure of printing cylinders for the purpose of improving operation performance. [Description of the Prior Art] As a printing press for printing bank notes and other securities, a satellite-type printing press for simultaneous multicolor printing has been known. (JP 63-132054) In this printing press, a plurality of plate cylinders are arranged in a satellite form around a single gathering rubber cylinder, and the multicolor printing is performed at the same time by applying the printing pressure while feeding printing paper in between an impression cylinder or a rubber blanket cylinder revolving in contact with the gathering rubber cylinder. The printing press of this type is capable of obtaining peculiar printed matters without miss-registering. Fig. 5 schematically shows the constitution of the satellite-type printing press. On a frame 1 of a printing press body are supported a pair of rubber blanket cylinders 2. Around each of these rubber blanket cylinders 2 are mounted, in a satellite form, a plurality (four in the illustrated example) of plate cylinders 3, which revolve in contact with the rubber blanket cylinders 2. To each of the plate cylinders are connected a plurality of inking arrangements 4, which are mounted to a frame 5 of the inking arrangement unit. These inking arrangements 4 are designed to supply printing ink to the plate cylinders 3. The sheet is fed from a sheet feeder into a pair of rubber blanket cylinders 2, and is fed out, after printing on both sides thereof, to a delivery apparatus not illustrated. In the satellite-type printing press shown in Fig. 5, the printing pressure is adjusted so as to be constantly a fixed value by shifting the position of the rubber blanket cylinders 2 in the event that the sheet to be printed has changed in thickness. When the position of the rubber blanket cylinders 2 is shifted, the printing pressure of both the plate cylinders 3 and the rubber blanket cylinders 2 varies; it is therefore necessary to shift each of the plate cylinders in accordance with the amount of movement of the rubber blanket cylinders 2. In the following, the movement mechanism of the plate cylinders 3 will be explained by referring to Fig. 6. The plate cylinders 3a and 3b are supported on both ends with eccentric sleeves 4a and 4b, which are revolvably mounted on the frame. On the eccentric sleeves 4a and 4b are rotatably mounted the plate cylinders 3a and 3b through bearings which are offset from the center of rotation C-1- of the eccentric sleeves 4a and 4b. The center of rotation C-2- of the plate cylinders 3a and 3b has an offset position set so that, during the operation of the printing press, a straight line between the center of rotation C-2- of the plate cylinders 3a and 3b and the center of rotation C-1- of the eccentric sleeves 4a and 4b will meet at right angles with the straight line between the center of rotation not illustrated of the rubber blanket cylinders 2 and the center of rotation C-1- of the eccentric sleeves 4a and 4b. With the rotation of the eccentric sleeves 4a, and 4b in relation to the frame, the center of rotation C-2- of the plate cylinders 3a and 3b changes its position, turning around the center of rotation C-1- of the eccentric sleeves 4a and 4b and accordingly enabling the retreat of the plate cylinders 3a and 3b from the rubber blanket cylinders 2 and printing pressure adjustment. In the flange section of either of the eccentric sleeves 4a and 4b, a sector gear 16 is fixedly mounted en bloc coaxially with the center of rotation C-1- of the eccentric sleeves 4a and 4b. The sector gear 16 is in mesh with a sector gear section 17 of a lever 18, which is integrally secured on either end of a connecting shaft 19 which is rotatably mounted through the frame. To the other end of the lever 18 of the connecting shaft 19, the top end section of a piston rod 21 of a fluid pressure cylinder 20a and 20b privotally mounted on the frame is connected through a pin 22 to actuate the fluid pressure cylinders 20a and 20b. Thus the arm 18 rotates together with connecting shaft 19, turning the eccentric sleeves 4a and 4b through the sector gear section 17 and the sector gear 16. Eccentric cams 25a and 25b are mounted, facing to the forward end of the piston rods 21 of the fluid pressure cylinders 20a and 20b. These cams are formed integral with printing pressure adjusting shafts 24a and 24b supported on the frame in parallel with the center of rotation C-2- of the plate cylinders 3a and 3b and rotate in contact with the forward end of the piston rods 21, thereby restricting the end of stroke of the fluid pressure cylinder 20a and 20b in the direction of rotation of the plate cylinders 3a and 3b which rotate in contact with the rubber blanket cylinder 2. That is, rotating the printing pressure adjusting shafts 24a and 24b changes the contact position between each piston rod 21 at one stroke end and the eccentric cams 25a and 25b, thus restricting the amount of rotation of the lever 18. Consequently the printing pressure of the plate cylinders 3a and 3b to be applied to the rubber blanket cylinders 2 can be changed. In the above-described printing press when the rubber cylinder 2 is moved, the eccentric sleeve 4 is rotated to shift the plate cylinders 3 in accordance with the amount of movement of the rubber cylinder 2, thereby keeping a constant printing pressure of the plate cylinders 3 to be applied to the rubber cylinder 2. However, since four plate cylinders 3 are mounted in contact with one rubber cylinder 2, it is necessary to adjust all of the plate cylinders 3 respectively, and in addition the eccentric sleeves 4 must be adjusted on both the control side and the driving side. Therefore when the sheet thickness of the printing paper has been changed, the adjustment of the eccentric sleeves 4 requires much time and labor. Summary of the Invention The present invention has been accomplished in an attempt to solve the problems mentioned above and has as its object the provision of a printing pressure adjusting apparatus as claimed in claim 1. Turning the eccentric bearing gives an eccentricity to the first cylinder, and accordingly the eccentric sleeves rotate to turn the second cylinder off-centered, applying the printing pressure to the first and second cylinders. When the amount of eccentricity of the first cylinder has been altered by adjusting the stop member, the restriction position of each stop member is also adjusted at the same time in accordance with the amount of adjustment of the stop member by means of the interlock mechanism, and the amount of eccentricity of the second cylinder is changed to keep a constant printing pressure between the first and second cylinders. The present invention and its features and advantages will be set forth and become more apparent in the detailed description of the preferred embodiment presented below, when read in connection with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an expanded sectional view of a rubber cylinder support section of a printing press equipped with a printing pressure adjusting apparatus according to one embodiment of the present invention; Fig. 2 is a view taken in the direction of the arrows along line II-II in Fig. 1; Fig. 3 is an expanded sectional view of a plate cylinder support section; Fig. 4 is a perspective view taken along line IV-IV in Fig. 3; Fig. 5 is a schematic view showing the construction of a satellite-type printing press; and Fig. 6 is a schematic view showing the construction of a conventional printing pressure adjusting apparatus. DESCRIPTION OF THE PREFERRED EMBODIMENT Fig. 1 is an expanded sectional view of a rubber cylinder support section of a printing press equipped with a printing pressure adjusting apparatus according to one embodiment of the present invention; Fig. 2 is a view taken in the direction of the arrows along line II-II in Fig. 1; Fig. 3 is an expanded sectional view of a plate cylinder support section; and Fig. 4 is a view taken in the direction of the arrows along line IV-IV in Fig. 3. As shown in Figs. 1 and 2, an eccentric metal 52 is rotatably fitted on a frame 51 on either of the control and drive sides of the printing press body. This eccentric metal 52 rotatably supports a rubber blanket cylinder 53 as a first cylinder through a bearing 65 which is off from the center of rotation. On the frame 51 is mounted a fluid pressure cylinder 54 for turning the eccentric bearing. A piston rod 55 of the fluid pressure cylinder 54 is connected to the eccentric bearing 52 through levers 56 and 57 and an adjusting rod 58. Therefore, when the fluid pressure cylinder 54 is driven to expand and contract the piston rod 55, the eccentric bearing 52 is rotated through the levers 56 and 57 and the adjusting rod 58, thus applying the printing pressure to the rubber blanket cylinder 53 rotating in contact therewith to perform printing. The amount of rotation of the eccentric bearing 52 is restricted by the H contact of the flange section 52a with a stopper 59 serving as a bearing stopper, thereby constantly maintaining a fixed printing pressure. regardless of the thickness of a sheet. In the following the construction of the stopper 59 will be explained. The frame 51 is provided with a stopper screw 60, which turns to move in the axial direction toward, or away from, the flange section 52a of the eccentric bearing 52. A first handle shaft 61 is installed through the frame 51 on the control side, and a handle 62 is mounted on the first handle shaft 61 on the outer side of the frame 51 on the control side. On the stopper screw 60 is fixedly mounted a worm gear 63. On the first handle shaft 61 is fixedly mounted a worm gear 64, which is meshed with a worm gear 63. That is, turning the first handle shaft 61 moves the stopper screw 60 in the axial direction through the worm gears 63 and 64, changing the position of contact of the flange section 52a of the eccentric bearing 52 to thereby change, the amount of rotation of the eccentric bearing 52, that is, the position of eccentricity of the rubber blanket cylinder 53. Around the rubber blanket cylinder 53 are arranged, in a satellite form, a plurality of plate cylinders 66 as the second cylinders, which rotate in contact with the rubber blanket cylinder 53 and are fed with the printing ink from an inking arrangement not illustrated. Eccentric sleeves 67 are revolvably fitted on the frame 51 on both the control and the drive side as shown in Figs. 3 and 4. On these eccentric sleeves 67 are rotatably supported the plate cylinders 66 through a bearing 68 off-centered from the center of revolution. A sleeve revolving cylinder (hereinafter referred to merely as the cylinder) 69 is mounted on the frame 51, and a piston rod 70 of the cylinder 69 is connected to the eccentric sleeve 67. When the cylinder 69 is driven to actuate the piston rod 70, the eccentric sleeve 67 revolves to adjust the printing pressure of the rubber blanket cylinder 53 to the plate cylinder 66. On the opposite side of the connection (point of application) between the eccentric sleeve 67 and the piston rod 70, across the center of revolution, an eccentric cam 71 as a stopper is located in contact with a flange section 67a of the eccentric sleeve 67. The flange section 67a contacts the outer periphery of the cam section 71 a of the eccentric cam 71 to restrict the amount of revolution of the eccentric sleeve 67, consequently enabling the adjustment of the printing pressure of the plate cylinder 66 to the rubber cylinder 53. Also since the connection of the piston rod 70 and the contact section of the flange section 67a contacting the cam section 71a are located on both sides of the center of rotation of the eccentric sleeve 67, a unidirectional force F 1 , F 2 and its reaction F 3 act on the eccentric sleeve 67 as shown in Fig. 4 when the cylinder 69 has been driven to move the eccentric sleeve 67 to the end of revolution. Therefore the eccentric sleeve 67 is pressed in one direction against the frame 51, leaving no play therebetween. Next, the construction of the eccentric cam 71 will be explained. As shown in Fig. 3, the eccentric cam 71 consists of a shaft section 71b fitted on the frame 51 and the cam section 71a off-centered from the shaft section 71b arranged inside of the frame 51. With the rotation of the shaft section 71b the outer peripheral surface of the cam section 71a changes in position relative to the flange section 67a of the eccentric sleeve 67, thus adjusting the position of contact of the flange section 67a, that is, the amount of rotation of the eccentric sleeve 67. The movement of the stopper screw 60 and the rotation of each eccentric cam 71 are interlockingly performed. In the following the interlock mechanism will be explained. As shown in Figs. 1 and 2, the printing pressure adjusting disk (hereinafter referred to merely as the disk) 72 is rotatably supported on the eccentric bearing 52. On the disk 72 is fixed a concentrical segment gear 73. In the meantime, a bevel gear 74 is fixedly mounted on the first handle shaft 61. On the frame 51 a shaft 75 is rotatably supported, extending as far as the position of the segment gear 73 from the position of the first handle shaft 61. Fixedly mounted on one end of the shaft 75 on the first handle shaft 61 side is a gear 76 which is engaged with the segment gear 73, and on the other end of the shaft 75 on the segment gear 73 side is mounted a gear 77 in mesh with the segment gear 73. With the rotation of the first handle shaft 61 the shaft 75 is turned through the bevel gears 74 and 76, and further the disk 72 is turned in relation to the eccentric metal 52 through the gear 77 and the segment gear 73. Links 78 are rotatably supported at their one end on the disk 72 in positions corresponding to the plate cylinders 66. As the disk 72 rotates, the eccentric cam 71 is turned through the link 78 and a lever 79 in accordance with the amount of rotation of the disk 72. That is, when the first handle shaft 61 is turned to move the stopper screw 60, the eccentric cam 71 is also turned through the disk 72 at the same time to change the position of the plate cylinder 66 to the position of the rubber blanket cylinder 53, thereby maintaining a constant printing pressure of the rubber blanket cylinder 53 and the plate cylinder 66. The plate cylinders 66 differ in the phase of eccentricity from each other. When the rubber blanket cylinder 53 rotates eccentrically, the printing pressure of all of the plate cylinders 66 to the rubber blanket cylinder 53 can be maintained at a constant value. Next, the manual rotational mechanism of the eccentric cam 71 will be explained. As shown in Fig. 3, a gear sleeve 80 is rotatably supported on the frame 51. On this gear sleeve 80 is rotatably supported the shaft section 71 b of the eccentric cam 71. A second handle shaft 81 is rotatably mounted through the frames 51 on the control and drive sides, and a gear 82 in mesh with a gear section 80a of the gear sleeve 80 is fixedly mounted on the second handle shaft 81. As the second handle shaft 81 is turned, the gear sleeve 80 rotates through the gear 82 and the gear section 80a, thus changing the position of the cam section 71a of the eccentric cam 71. Since the gear sleeve 80 and the eccentric cam 71 are designed to be rotatable, an input power from the lever 79 side is not transmitted to the second handle shaft 81 side. The positions of the plate cylinders 66 can be separately adjusted by changing the position of the eccentric cam 71 in accordance with an input power from the interlock mechanism side of the stopper screw 60 and the second handle shaft 81 side. Next, the operation of the printing pressure adjusting apparatus of the above-described constitution will be explained. When the fluid pressure cylinder 54 operates to expand or contract the piston rod 55, the eccentric bearing 52 turns to apply the printing pressure between the contiguous rubber blanket cylinders 53, thus performing printing operation. The flange section 52a of the eccentric bearing 52 contacts the stopper 59 to restrict the amount of revolution of the eccentric bearing 52, thereby maintaining a constant printing pressure notwithstanding the thickness of the sheet. The purpose of the fluid pressure cylinder 54 is to move the rubber blanket cylinders 53 into contact with, and away from, each other (during printing, the rubber blanket cylinders 53 are fed into contact with each other, that is, the printing pressure is applied; and when no printing is done, the rubber blanket cylinders 53 are moved away from each other). The adjustment of the printing pressure is done not by the revolution of the eccentric bearing 52, but done by the amount of revolution of the eccentric bearing 52 (the amount of restriction of the stopper 59). This similarly applies to the cylinder 69 which will be described later. When the cylinder 69 is operated, the piston rod 70 is actuated to turn the eccentric sleeve 67, and accordingly the eccentric position of the plate cylinder 66 moves to apply the printing pressure between the plate cylinder 66 and the rubber blanket cylinder 53, thus transferring an image from a printing plate of the plate cylinder 66 to a rubber blanket surface. Then the flange section 67a of the eccentric sleeve 67 contacts the cam section 71a of the eccentric cam 71, restricting the amount of revolution of the eccentric sleeve 67. Accordingly, in the state that the printing pressure is being applied, the position of the plate cylinder 66 changes to always maintain a constant printing pressure between the plate cylinder 66 and the rubber blanket cylinder 53. The rotation of the eccentric sleeve 67 alone can be adjusted by turning the second handle shaft 81 which in turn rotates the gear sleeve 80 to change the position of the cam section 71a of the eccentric cam 71. The eccentric position of the rubber blanket cylinder 53 can similarly be adjusted by turning the first handle shaft 61 which moves the stopper screw 60 in the axial direction to change the position of contact of the flange section 52a of the eccentric metal 52. As the first handle shaft 61 is turned, the disk 72 is turned through the bevel gears 74 and 76, the gear 77 and the segment gear 73, thereby rotating the eccentric cam 71 through the link 78 and the lever 79. Thus the amount of rotation of the eccentric sleeve 67 is adjusted in accordance with the amount of movement of the stopper screw 60, and the eccentric position of the plate cylinder 66 is changed with a change in the eccentric position of the rubber blanket cylinder 53, keeping a constant printing pressure between the rubber blanket cylinder 53 and the plate cylinder 66. In the above-described printing pressure adjusting apparatus, the connection of the piston rod 70 of the eccentric sleeve 67 and the contact section of the flange section 67a of the eccentric sleeve 67 which rotates in contact with the cam section 71a are situated on the opposite sides across the center of revolution of the eccentric sleeve 67. The eccentric sleeve 67, therefore, is pressed in one direction against the frame 51, leaving no play therebetween. Therefore, the plate cylinder 66 will never vibrate and move if it receives the printing pressure intermittently. Furthermore, when the first handle shaft 61 is turned to adjust the stopper screw 60, all of the eccentric cams 71 also can be adjusted at the same time in accordance with the amount of adjustment of the stopper screw 60. Accordingly when the position of the rubber blanket cylinders 53 is changed, a constant relationship between the rubber blanket cylinders 53 and all of the plate cylinders 66 can be maintained at all times without a special adjustment on the plate cylinder 66 side, thereby enabling performing printing operation at the constant printing pressure by a simple operation. In one embodiment described above, the rubber blanket cylinders 53 and the plate cylinders 66 have been explained as the first and second cylinders, but the present invention should not be limited thereto. Also, the stopper screw 60 moving in the axial direction has been shown as the stopper 59 of the eccentric metal 52, but a stopper of other mechanism such as an eccentric cam may be used. The printing pressure adjusting apparatus of the present invention is equipped with the interlock mechanism which simultaneously changes the regulating positions of the stoppers at the time of metal stopper adjustment for the purpose of maintaining a constant state of contact between the first and second cylinders. When, therefore, the amount of eccentricity of the first cylinder has been changed by adjusting the metal stopper, the regulating position of each stopper is adjusted by means of the interlock mechanism at the same time in accordance with the amount of metal stopper adjustment, thereby changing the amount of eccentricity of the second cylinder in such a state that the printing pressure of the first cylinder can be kept constant. In consequence, the printing pressure adjustment can be done with little labor and time, thereby improving operation performance. The present invention has been described in detail with particular reference to preferred embodiments thereof but it will be understood that variations and modifications can be effected within the scope of the invention as defined in the appended claims.

Claims: A printing pressure adjusting apparatus of printing cylinders of a printing press in which a plurality of second cylinders (66) revolve in contact with one first cylinder (53), said printing pressure adjusting apparatus, comprising: an eccentric bearing (52) revolvably fitted on a frame (51) of said printing press and revolvably supporting said first cylinder (53) in an eccentric state: eccentric sleeves (67) revolvably fitted in positions opposite to said first cylinder (53) on said frame (51) of said printing press and revolvably supporting said second cylinders (66) in an eccentric position; a stop means (59) for adjustably regulating the revolving position of said eccentric bearing (52); a stopper (71) for adjustably regulating the revolving position of said eccentric sleeves (67); and an interlock mechanism for constantly maintaining the state of contact between said first (53) and second (66) cylinders by simultaneously changing each stopper (71) in adjusting the stop means (59), said interlock mechanism being provided with a disk (72) rotatably disposed on the eccentric bearing (52) of the first cylinder (53) through which disk (72) the stopper (71) and the stop means (59) move in cooperation. A printing pressure adjusting apparatus as claimed in claim 1, wherein said stop means (59) restricts the rotating position of said eccentric bearing (52). A printing pressure adjusting apparatus as claimed in claim 1, wherein said stopper (71) restricts the rotating position of said eccentric sleeve (67). A printing pressure adjusting apparatus as claimed in claim 1, wherein said interlock mechanism comprises a shaft (75) rotating in accordance with the amount of movement of said stop means (59), said disk (72) rotated by the rotation of said shaft (75), and a link mechanism (78, 79) mounted correspondingly to each stopper (71).

Inventors: FUNADA HITOSHI, FUNADA, HITOSHI, FUNADA, HITOSHI, C/O KOMORI CORP.
Applicants: KOMORI PRINTING MACH, KOMORI CORPORATION
Application year: 1992
Main classification: B41F13
IPC codes: B41F13