The present invention relates to a cylinder apparatus in a sheet-fed offset rotary printing press with a turn-over mechanism, for adjusting, with respect to the grippers of a double-diameter cylinder, the phase of a phase-changeable suction member which draws by suction and holds the trailing edge of a sheet gripped and conveyed by the grippers and for fixing the suction member to a cylinder body.
As shown in U.S. Pat. No. 4,831,929, a conventional cylinder apparatus for a printing press has a cylinder body having an axial hole extending through the central portion in the axial direction, a pair of left and right side plates which are in contact with the two end faces of the cylinder body and support suction heads, press rods which urge the side plates against the two end faces of the cylinder body and fix the side plates to the cylinder body, and a fixing shaft which is inserted in the axial hole of the cylinder body and moved to fix and release the side plates to and from the cylinder body with the press rods.
According to the structure of the conventional cylinder apparatus, when the fixing shaft is to be moved in the axial direction in the axial hole of the cylinder body in order to adjust the phase of a suction head with respect to the gripper, a screw member threadably engaging with the fixing shaft is pivoted manually. This operation not only poses a burden to the operator but also cannot be automatized.
It is an object of the present invention to provide a cylinder apparatus in which the burden to the operator is decreased and automatization is facilitated.
In order to achieve the above object, according to the present invention, there is provided a cylinder apparatus comprising a cylinder body rotatably supported by a pair of frames, a support mechanism which is supported to be movable in a circumferential direction with respect to the cylinder body and supports a operating member, a shaft supported to be movable in an axial direction of the cylinder body, a first elastic member which biases the shaft in a first direction, driving means for moving the shaft in a second direction opposite to the first direction against an elastic force of the first elastic member, and first and second levers which are swingably supported by the cylinder body and swing upon movement of the shaft to fix/release the support mechanism with respect to the cylinder body.
A cylinder apparatus according to one embodiment of the present invention will be described with reference to
First, the schematic arrangement of a printing press of this type will be described with reference to
Of these cylinders, the transfer cylinder 11 includes gripper units 16 each consisting of a gripper 14 and gripper pad 15 (to be referred to as the gripper unit 16 hereinafter) in a gap formed in the outer peripheral portion of the transfer cylinder 11. The double-diameter cylinder 12 has a diameter twice that of the transfer cylinder 11 and the like. Two sets of gripper units 19 and 20 each consisting of a gripper 17 and gripper pad 18 (to be referred to as the gripper units 19 and 20 hereinafter) are arranged at positions of equal angular intervals of the outer peripheral portion of the double-diameter cylinder 12. Suction heads (suction members) 21 and 22 serving as operating members fixed by splitting and fastening to a suction pipe 41 (to be described later) are disposed at positions advancing from the gripper units 19 and 20 by a predetermined angle in the rotating direction of the cylinder.
The suction heads 21 and 22 include a plurality of suction heads that are arranged on the outer peripheral portion of the double-diameter cylinder 12 along the axial direction so as to be parallel to each other. The suction heads 21 and 22 are supported to be movable in the circumferential direction, so that a phase with respect to the gripper units 19 and 20 in the circumferential direction can be adjusted. Gripper units 25 each consisting of a gripper 23 and gripper pad 24 (to be referred to as the gripper units 25 hereinafter), and gripper units 28 each consisting of a gripper 26 and gripper pad 27 (to be referred to as the gripper units 28 hereinafter) are disposed in gaps formed in the outer peripheral portion of the turn-over cylinder 13, to be adjacent to each other in the circumferential direction. The cylinders 1, 5, 11, 12, 13, 10, and 6 are driven and coupled by gears. A stationary gear fixed to a shaft and a pivotal gear are fixed to one end shaft of the turn-over cylinder 13 of these cylinders such that the stationary and pivotal gears can be fixed and released. The stationary gear meshes with the gear of the impression cylinder 10. The pivotal gear meshes with the gear of the double-diameter cylinder 12.
With this embodiment, in the case of single-side printing shown in
When the single-side printing mode is to be switched to the double-side printing mode, the pivotal gear is pivoted from a state wherein the gripper units 19 and 25 oppose each other (
When the respective cylinders are rotated after the switching adjustment is performed in this manner, the sheet 30 subjected to printing on a front surface, in the same manner as in single-side printing, is conveyed while being gripped by the gripper units 19 (20) of the double-diameter cylinder 12 and drawn by suction at its trailing edge by the suction heads 21 (22). The sheet 30 is conveyed until its trailing edge reaches the contacting point between the two cylinders 12 and 13, as indicated by reference numeral 30A. At this time, the trailing edge of the sheet 30A is gripped upon opening/closing of the gripper units 28 and suction/release of the suction heads 21. Simultaneously, the gripper unit 20 releases the leading edge of the sheet 30A. Then, the sheet 30A is conveyed by the turn-over cylinder 13 while forwarding the trailing edge side.
During the conveyance, both the gripper units 25 and 28 instantaneously open and close at different timings, and the sheet 30A is gripped by the gripper units 25 from the gripper units 28, and is conveyed. When the gripper units 25 and the gripper units 9 of the impression cylinder 10 oppose each other, the sheet 30A is gripped by the gripper units 9, and is conveyed as indicated by reference numeral 30B. When the sheet 30B passes between the blanket cylinder 6 and impression cylinder 10, its rear surface is in contact with the blanket cylinder 6, so that the rear surface is subjected to printing. In this manner, the sheet 30B is double-side printed because of previous front-surface printing and current rear-surface printing, and is delivered.
In the three-roller-type sheet-fed offset rotary printing press with the turn-over mechanism which operates in this manner, the gripper units 19 and 20 for gripping the leading edge of the sheet 30 and the suction heads 21 and 22 for chucking the trailing edge of the sheet 30 are provided to the double-diameter cylinder 12, as described above. The phase in the circumferential direction between the gripper units 19 and suction heads 21 and between the gripper units 20 and suction heads 22 must be adjusted when the printing mode between the single- and double-side printing modes or when the sheet size is to be changed. More specifically, as shown in
Referring to
First and second support members 38 and 39 are pivotally fixed on large-diameter portions 32a and 33a of the two end shafts 32 and 33, respectively. The first and second support members 38 and 39 include O-shaped ring portions 38b and 39b and two arm portions 38c and 39c projecting from the ring portions 38b and 39b outwardly at an angular interval of 180°. The first and second support members 38 and 39 are regulated from moving inwardly as they abut against the end faces of the cylinder body 31, and from being removed outwardly by removal preventive members 40 fixed to the end shafts 32 and 33. The first and second pivotal support members 38 and 39 are fixed to the cylinder body 31 with fixing devices (to be described later). Suction pipes 41 are pivotally, axially supported by the arm portions 38c and 39c of the first and second support members 38 and 39 through bearings 42. Air in the suction pipes 41 is drawn by the pivotal motion of the double-diameter cylinder 12 only at a predetermined timing.
As shown in
Suction member fixing operation of fixing the phase-adjusted suction heads 21 and 22, after phase adjustment, to the cylinder body 31 through the first and second support members 38 and 39 will be described.
Axial holes 46, 47, and 48 are formed at the central portion of the cylinder body 31 and at the central portions of the two end shafts 32 and 33, respectively, such that the axial holes 46, 47, and 48 extend between the two end shafts 32 and 33. A large-diameter portion 48a is formed on the end side of the axial hole 48, and a step 48b is formed at the boundary at the center of the large-diameter portion 48a. First and second lever storing holes 50 and 51 are respectively formed at those portions of the two end shafts 32 and 33 which are to be connected to the cylinder body 31. The first and second lever storing holes 50 and 51 are recessed from the circumferential surfaces of the two end shafts 32 and 33, respectively, in the radial direction. The distal end sides (bottom portion sides) of the lever storing holes 50 and 51 intersect with the axial holes 46, 47, and 48 perpendicularly.
As shown in
As shown in
A shaft 60 extends through the through holes 55 and 58 of the first and second levers 52 and 56, respectively, and is inserted in the axial hole 46 of the cylinder body 31 and the axial holes 47 and 48 of the end shafts 32 and 33. The shaft 60 has first and second small-diameter portions 61 and 62 at its two ends, and steps 60a and 60b at its boundaries with the first and second small-diameter portions 61 and 62, respectively. Threaded portions are formed on the two ends of each of the first and second small-diameter portions 61 and 62.
As shown in
In this arrangement, the shaft 60 is biased in the direction of the arrow A by the spring force of the coned disc spring 65. The step 60b of the shaft 60 engages with the step 58a of the axial hole 58 of the second lever 56, and the second lever 56 swings counterclockwise in
The first lever 52 is biased by the spring forces of the compression coil springs 71 and 72 through the second spring bearing member 69, and pivots counterclockwise in
In this manner, when the first and second support members 38 and 39 are to be fixed to the cylinder body 31, the first and second levers 52 and 56 are biased by the compression coil springs 71 and 72 and coned disc spring 65 in a shared manner. Thus, the first and second support members 38 and 39 can be reliably fixed to the cylinder body 31 with the first and second levers 52 and 56.
In addition, as shown in
The first and second levers 52 and 56 respectively press and fix the first and second support members 38 and 39 to the two end faces of the cylinder body 31 by the leverage. More specifically, as shown in
Similarly, as shown in
Consequently, the spring forces of the compression coil springs 71 and 72 and the spring force of the coned disc spring 65 can be decreased.
The leverage L11/L12 of the first lever 52 is set larger than the leverage L21/L22 of the second lever 56. As described above, since the spring forces of the compression coil springs 71 and 72 are set smaller than the spring force of the coned disc spring 65, the pressing force of the first lever 52 against the first support member 38 and the pressing force of the second lever 56 against the second support member 39 are set almost equal to each other as a whole. Accordingly, the pressing force of the first support member 38 and that of the second support member 39 at the two ends of the cylinder body 31 become equal to each other.
Suction member releasing operation which enables the first and second support members 38 and 39 to move with respect to the cylinder body 31, so that the suction heads 21 and 22 can be phase-adjusted, will be described.
Referring to
In this arrangement, when the working rod 83a of the first air cylinder 83 moves backward, the driving bar 85 pivots counterclockwise as indicated by an alternate long and two short dashed line about the shaft 86 as the pivot center. As the driving bar 85 pivots, the wheel 87 presses the fixing element 63, and the shaft 60 moves slightly in a direction of an arrow B as the second direction against the spring force of the coned disc spring 65. Thus, in
Simultaneously, as the shaft 60 moves in the direction of the arrow B, its step 60a engages with the bottom surface 69a of the second spring bearing member 69, as shown in
According to this embodiment, the spring forces of the coned disc spring 65 and compression coil springs 71 and 72 can be decreased, and the driving bar 85 uses leverage. Hence, the driving force of the first air cylinder 83 can be decreased, so that the first air cylinder 83 can be downsized.
Referring to
A second air cylinder 97, the cylinder end of which is pivotally mounted on one frame 35, has a working rod 97a which is pivotally mounted on the other end of the lever 92 and can move forward/backward. When the working rod 97a of the second air cylinder 97 moves forward, the pivotal shaft 90 pivots clockwise in
In this arrangement, when the sheet size is changed and accordingly the rotational phase of the suction heads 21 and 22 with respect to the gripper units 19 and 20 of the double-diameter cylinder 12 is to be changed, first, the double-diameter cylinder 12 is pivoted to a predetermined position. Subsequently, the working rod 97a of the second air cylinder 97 moves forward to pivot the pivotal shaft 90 clockwise in
In this state, the printing press motor 37 is driven, so that the double-diameter cylinder gear 36 is pivoted through a predetermined pivot angle, and the cylinder body 31 is also pivoted together with the double-diameter cylinder gear 36 through the predetermined angle. Simultaneously, the gripper units 19 and 20 of the cylinder body 31 also pivot integrally, so that the rotational phase of the suction heads 21 and 22 supported by the first and second support members 38 and 39 with respect to the gripper units 19 and 20 is changed.
In this state, when the first air cylinder 83 is driven, the first and second support members 38 and 39 can be fixed to and released from the cylinder body 31. Hence, when compared to the conventional apparatus, the burden to the operator can be decreased and the operation can be automatized.
When the working rod 83a of the first air cylinder 83 moves forward and the driving bar 85 pivots clockwise to the position indicated by a solid line in
After the rotational phase of the suction heads 21 and 22 is changed, when the working rod 97a of the second air cylinder 97 moves backward, the pivotal shaft 90 pivots counterclockwise in
In this embodiment, the cylinder of the printing press has been described. The present invention can also be applied to adjustment of the phase between a gripper and suction head in a coater apparatus which coats the two surfaces of a sheet. A case has been described wherein the phase between the gripper and the suction head as a operating member is to be adjusted. The present invention can also be applied to adjustment of a phase between a pin in the folding cylinder of a folding machine and a knife as a operating member, or to adjustment of a phase between a pin as a operating member and a knife.
As has been described above, according to the present invention, the burden to the operator can be decreased and the operation can be automatized. Since the support member is fixed to the cylinder body by using the leverage, the spring force of the first elastic member can be decreased, and accordingly the driving device can be downsized. When fixing the support member to the cylinder body, the two levers are biased by the first and second elastic members in a shared manner. Thus, the support member can be fixed to the cylinder body with the two levers reliably. Also, wear of the driving device during printing operation can be prevented.
Number | Date | Country | Kind |
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2003-326925 | Sep 2003 | JP | national |
Number | Name | Date | Kind |
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4831929 | Saito | May 1989 | A |
5105737 | Becker | Apr 1992 | A |
5365845 | Becker | Nov 1994 | A |
Number | Date | Country |
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1012566 | May 1991 | CN |
Number | Date | Country | |
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20050061179 A1 | Mar 2005 | US |