US2874636A

US2874636A - Cylinder throwoff for rotary offset machine

Info

Publication number: US2874636A
Application number: US382381A
Authority: US
Inventors: Arthur G Royer; William J Thompson
Original assignee: Harris Intertype Corp
Current assignee: Harris Corp
Priority date: 1953-09-25
Filing date: 1953-09-25
Publication date: 1959-02-24
Anticipated expiration: 1976-02-24

Description

Feb. 24, 1959 A. G. ROYIER' I 'I'IAL 2,874,635

' CYLINDER THROWOFF FOR ROTARY OFFSET MACHINE Filed Sept. 25. 1953 '7 2 Sheets-Sheet 1 INVENTOKS 492mm 6. Force y MAL/AM [Mesa/v m Mp Afro I Y5 Feb. 24, 1959 4 A. G. ROYER ETAL 2, 7 CYLINDER THROWOFF FOR ROTARY OFFSET MACHINE Filed Sept. 25. 1953 2 Sheets-Sheet 2 INVENTORS I 49730.? 6- flora-R United States Patent Ofiice 2,874,636 I Patented Feb. 24, 1959 CYLINDER THROWOFF FOR ROTARY OFFSET MACHINE Arthur G. Royer, Cleveland Heights, and William J.

Thompson, Cleveland, Ohio, assignors to Harris-Inter type Corporation, Cleveland, Ohio, Delaware a corporation of This invention relates to improvements. in cylinder throwoffs, especially means for throwing ofi cylinders that are arranged with their axes approximately in a single plane, and especially also in perfecting offset presses where the paper to be printed passes between two blanket cylinders each of which acts as the impression cylinder for the other.

In a multicolor printing press of the latter type it is desirable that the difierent cylinders of each unit be arranged approximately one above another so as to conserve space while permitting the press attendants to work comfortably between units. In order to adapt throwoff means to such a unit we have devised mechanism for throwing oif the movable or less vertical direction, and since three cylindersmust be moved to accomplish the complete throwotf operation we have devised means for simultaneously moving two cylinders inopposite directions a like amount and for moving one of the outermost cylinders a greater distance sulficient to separate it from the next'adjacent moved cylinder. 7

7 One of the objects of the invention therefore is the provision of means for the simultaneous movement of three cylinders outwardly away from adjacent cylinders to separate two cooperating blanket cylindersand to separate the two plate cylinders from the adjacent blanket cylinders. I p a e Another object of the invention is the provision of lever and link means for accomplishing in a single operation the separating movements above referred to.

Another object is the provision of means for moving a pair of cylindersin the same general direction with respect .to a third cylinder, with the .farthest one; from the third cylinder being moved az greater distance than the other.

A further objectis the provision of: mechanism of the.

type indicated providing. maximum accessibility for the operator to the clinders of each unit of a multiunit perfecting printing press. e 1 j 1 Still amt er. object is the provision of a novel toggle mechanism .for separating'a pair of cylinders radially from; a" third stationary cylinder by movingthe outer cylinder aQ greate'r distance than the -;one adjacent the thirdeylinderj'. o. 2 I

I Other :ob ctsoand: featuresiof novelty willj appear'as we proceed'fwithf the description of that-embodiment of thein'vention which for the purposes ofthe'present application we have illustrated the accompanying drawings, in which T perfecting rotary offset p ess embodying f p invention,

theqcylinders being shown imprinting relation; M

Fig. 2 is a. similar view shwirig. themechanism in the throwofi position and eachbf fthefour cylinders of; the

" SFParated om: he ia enticyl nder 5 tially on theline 3-j-3 ofFig. ,1 ;;andft:

cylinders in a more,

e View of I one unit of p a- Fig. 4 is a fragmental plan view looking in the direction of arrows 4-4 of Fig. 1.

In the drawings a fragment of one side of the frame of a rotary perfecting ofiset press is indicated at 10. In the frame there is mounted in fixed bearings an upper blanket cylinder 11. A lower blanket cylinder 12 has a shaft 13'which is journaled ina pair of eccentrics 14, each of which is oscillatably mounted in one of the side walls ofthe frame. An upper plate cylinder 15 has a shaft 16 which is journaled in a pair of eccentrics 17, one only of which is illustrated, and a lower plate cylinder- 18 has a shaft 19 which is journaled in a pair of eccentrics 20, each of which is oscillatably mounted in a wall of the machine frame- Each of the eccentrics of the three

pairs

14, 17 and 20 has a radial ear or

throw arm

21, 22 and 23 respectively, by means of which it may be turned in its mounting. To one side of the unit there is oscillatably mounted in the opposite walls of thefram e a hollow shaft 25 which projects at each end. somewhat outwardly of the frame. In this hollow shaft there is oscillatably mounted a second shaft 26 which extends through the machine and projects somewhat beyond the ends of the hollow shaft, as indicated in Fig. 3. On the hollow shaft 25 outwardly of each side wall 10 there is keyed a short lever 27, and on shaft 26adjacent the two levers 27 there are keyed two bell Fig. 3. is a fragmentalj sectional viewhtaken. substam crank levers 2 8.

The two shafts 25and 26 are angularly adjustable with respect to each other and the adjusting means is preferably such that it functions also to lock the shafts together in adjusted position. To this end there is mounted in one ofthe bell crank levers 28 a shaft 30 having a knob or-wheel 31 by means of which it may be turned by the operator. Shaft 30 carries a worm 32 which meshes with a worm wheel 33 on the lower end of a shaft 34, near the upper end of which there is a second worm 35 which meshes with a worm wheel sector 36 that is integral with lever 27. Since the levers 28 are keyed to shaft 26 and the levers 27 are keyed to shaft 25, these two shafts are adjustable with respect to each other by means of the worm and worm wheel mechanism described and are locked in adjusted position, and the levers 2 7. and. 2 8 on the far side of the machine move through the same arcs as those on the near side to which the adjusting mechanism is attached. The upper arm 37 ofthe bell crank lever 28 oneach side of the machine carries a pivot 38 to which is connected the lower end of a link 39 which connects the bell crank with a lever 40 that is pivoted at 41 to the machine frame opposite'the upper plate cylinder 15. The other end of lever 40is connected by a pivot 42 to a link 43 which is of link for length adjustment. Extending from this same pivot 47 there is a link 48 which forms one arm of a toggle connection, the other arm of which is connectedat the elbow joint 49 of the toggle with a link 50 which extends through a'smooth hole ina pivot 51 carried by the ear-23 on eccentric 20.

Nuts

52 and 53 threadably mounted on link 50 engage pivot 51 and maybe adjusted to vary the length of the link. To the,

lower-arm 5 4 of the bell crank 28 there is pivotally con O nected at 55 a link 56 which extends over to and is pivotally connected with the elbow joint 49 of the toggle connection.

In order to obtain a mechanical advantage in throwing-on the movable cylinders of the unit and in order to provide maximum resistance to accidental throwing-off of the cylinders, the operating mechanism for turning the combined

levers

27 and 28 embodies a toggle device. This device comprises two toggle arms 60 and 61 connected together at their inner ends by a pivot-'62 constituting an elbow joint. The outer end of arm 60 extends into a space formed between the lower'arm 54 of bell crank 28 and a short offset arm 63. A pivot 64 extends through the

arms

54, 60 and 63. The outer end of toggle arm 61 is pivoted at 65 to a bracket 66 that is mounted on the frame.

' Suitable means is provided for moving the elbow joint 62 from the position of Fig.1 to that of Fig. 2 and back again. The means which we prefer is a fluid cylinder 68, a piston therein, not shown; a piston rod 69 extend ing downwardly from the piston and connected with the elbow joint 62, and means, not shown, for directing incoming pressure fluid into one or the other of the chambers above and below the piston and exhaustingg it from the other chamber. The downward travel of the piston in cylinder 68 is so limited thatthe elbow joint 62 cannot pass beyond the position shown in Fig. 1.

If something occurs which requires that the impression in the unit be thrown off, a control is operated in known manner to energize electrical or other means for operating a valve, not shown, in the head of cylinder 68 to introduce pressure fluid into the cylinder below the piston. Piston rod 69 will then rise, breaking the toggle 60, 61 and putting the various parts of the throwoii mechanism in the positions of Fig. 2. The bell crank lever 28 isthus turned counterclockwise which transmits a clockwise movement to lever 40 and turns eccentric 17 counterclockwise thereby shifting the shaft 16 and its cylinder -upwardly away from cylinder 11. At the same time short lever 27 is turned counterclockwise through the same angle as lever 28, thereby lifting link 46 and turning eccentric 14 clockwise. This throws cylinder 12 downwardly off cylinder 11. A similar downward movement is communicated to cylinder 18 since links 48 and 50 hang from link 46, and their upward movement turns eccentric clockwise'at the same time that eccentric 14 is turned clockwise. However, at the same time that the links 46, 48, 50 are drawn upwardly, toggle mechanism 48, 50 is broken by the'link 56 pushing elbow joint 49 to the right, and this adds an additional turn to eccentric 20 clockwise to effect separation between cylinders 12 and 18. 1

One of the advantages of the cylinder arrangement disclosed herein is that the major part of the surface of each plate cylinder is free of any close proximity to any other parts of the unit. Hence there is an abundance of room for the mounting of the inking and dampening mechanisms, and this is of special importance where the width of the press is great because then the inking rollers may be made of relatively large diameter for purposes of strength.

The printing pressure between the two blanket cylinders 11 and 12 is regulated by manipulation ofthe knob or wheel 31. This adjustment is performed when the toggle connection 60, 61 is in the condition of Fig. 1. Lever 28 is held against movement by the locked toggle. The turning of knob 31 therefore functions return lever 27 and eccentric 14. Eccentric 17 is not affected and hencethe bearing pressure between cylinders 11 and 15 remains as it was. cylinders 12 and 18 also remains unaffected when the setting of knob 31 is changed because the two

eccentrics

14 and 20 are disposed in the same angular relation and have corresponding eccentricities andathrow .arm.

lengths and any adjustment of lever 27 is-equallyeffec- The bearing pressure between tive upon both

eccentrics

14 and 20. The pressure between cylinders 12 and 18 therefore remains the same unless the adjusting

nuts

52 and 53 are moved for adjustment purposes.

In one aspect of the invention cylinder 11 may be considered as an impression cylinder of a non-perfecting press, the cylinder 15 being omitted and the throwoff then affecting only the cylinders 12 and 18.

It is essential that the spacing of cylinders 11 and 12 be adjustable by the press operator to control the pressure between those cylinders to compensate for differences in the thickness of the paper stock to be imprinted, and it is important that such adjustment not affect the pressure between cylinders 11 and 15 or between cylinders 12 and 18. The mechanism of the present invention accomplishes this purpose. The result is due to the fact that the throw arms 21 and 23 are of the same length and that the eccentricities of the eccentrics 14 and New alike and are disposed at the same angle to the horizontal. When the two toggle arms 60, 61 are in alignment lever 28 is fixed against movement. The turning of knob 31 then swings lever 27 only, which does not affect eccentric 17. It operates through link 46 to turn eccentric 14 through a given angle. Since toggle links 48 and 50 are then in alignment they move the same distance as link 46 and turn eccentric 20 through the same angle as eccentric 14. Hence the pressure between cylinders 12 and 18 is not changed.

The throwoff of cylinder 18 from cylinder 12 could be accomplished by substituting a single straight link for the toggle links 48 and 50 and increasing the eccentricity of eccentric 20 over that of eccentric 14. But if that were done any adjustment of lever 27 to increase the distance between cylinders 11 and 12 would also increase the distance between cylinders 12 and 18, and any adjustment to decrease the distance between cylinders 11 and 12 would tend also to decrease the distance between cylinders 12 and 18. The latter would be impossible because of the bearers on those cylinders. Accordingly the use of like eccentricities for the eccentries 14 and 20 and the employment of the toggle links 48 and 50 to effect separation of cylinders 12 and 18 constitute'important features of the invention.

While in the preferred form the

eccentrics

14 and 20 have equal eccentricities and throw arms of equal length, it is within the purview of the invention to employ unequal eccentricities and throw arms provided the throw arm and eccentricity of one eccentric are in the same ratio as those of the other eccentric.

Having thus described our invention, we claim:

1. In a rotary offset printing press, an impression cylinder, a blanket cylinder in printing relation with said impression cylinder, a plate cylinder disposed on the side of the blanket cylinder remote from said impression cylinder, eccentrics in which said blanket and plate cylinders are rotatably mounted, said eccentrics having corresponding eccentricities and throw arms, a lever mounted on a fixed pivot disposed alongside said blanket cylinder, and mechanism comprising a link connecting said lever and the eccentric for said blanket cylinder and comprising connecting means'between said link and the eccentric for said plate cylinder, said mechanism being operative when said lever is turned in one direction to throw said blanket cylinder off from said impression cylinder and simultaneously to throw said plate cylinder off from said blanket cylinder, said mechanism comprising means for adjusting the pressure between said impression and blanket cylinders while maintaining unaffected the pressure between said blanket and plate cylinders;

2. In a rotary offset printing press, an impression cylinder, a blanket cylinder in printing relation with said impression cylinder, a plate cylinder disposed on the side of the blanket cylinder remote from said impression fi Xed pivot disposed alongside said blanket cylinderf a link connecting said lever and the eccentric forsaid blanket" cylinder, a toggle connection between said link and the eccentric for said plate cylinder, a link connecting said lever to the elbow joint of said toggletconnection, and

means for turning said lever on its pivot, whereby the throwolf of said plate cylinder resultsfrom the combined movements of both of said links and causes a throwolf movement of said plate cylinder greater in extent than that of said blanketcylinder. l

3 A printing press as defined in claim 2, wherein the I first of said linksand one of the arms of said toggle con nection have length adjustments for regulating the pressure of said blanket cylinder against said impression cylinder and said, plate cylinder against said blanket cylinder. t

14. A printing press as defined in claim 2, wherein said means for turning said lever comprises a toggle connection between the lever and a-fixed pivot, and means for movingtthe elbow joint of said lastnamcd toggle-connection intoor out of the line of centers of the outer pivots of said toggle connection. t l I 4 1" '5; printing press as, defined in claim 4', I wherein said meansfor moving said elbow joint comprises a fluid motorfcylinder and piston andta piston rod articulated of said blanket cylinders, eccentrics in which the lower:

blanket cylinder and both of said plate cylinders are rotatablymounted, a bell crank lever mounted on a fixed pivot .alongsidetsaid unit, a second levermountedrona fixed pivot alongside said upper plate cylinder, a link? connectingone arm of said bell crank and one arm of said second lever and a link connecting the other arm ofsaid second lever with the eccentric for said upper plate-cylinder, a link connecting one arm ofsaid'bell crank and the eccentric for said lower blanket cylinder, a toggle connection between the lower end of said last named link and the eccentric for said lower plate cylinder, and a link connecting the elbow joint of said toggle connection with the other'arrn ofsaid bell' crank lever,and means for turnin'gsaid bell 'cranklever on 'it's pivot, whereby in a single operation said upper' plate cylinder and said lowerblanket cylinder ma be thrown off from said upper blanket cylinder and said lower plate cylinder may be thrown off from saidlower blanket cylinder. f ,3 I

8-, ;A rotary oifset prir 1ting press as defined in claim 7, wherein the eccentrics for said lower blanket cylinder and said lower plate cylinder have the same eccentricities.

9. In a rotary offset printing press, a perfecting unit comprising a pair of cooperating blanket cylinders between which the paper to be printed passes, one of said blanket cylinders being mounted in fixed bearings and the other being mounted in movable bearings, a plate cylinder on the side of said fixed blanket cylinder remote from said movable blanket cylinder, movable bearings for said plate cylinder, a shaft to one side of said unit, a lever keyed to said shaft, a second lever rotatable on said shaft, means for locking said levers together in different angular relations, means for swinging said interlocked levers through a given angle, and throwotf means extending from one of said levers to the movable bearings of said plate cylinder and from the other lever to the movable bearings of said blanket cylinder to cause separation' of said movable cylinders from said fixed cylinder.

10. In a rotary offset printing press, a perfecting unit comprising a pair of cooperating blanket cylinders between which the paper to be printed passes, one of said blanket cylinders being mounted in fixed bearings and cylinder mounted in fixed bearings, and throwoff means from the other lever to the bearings ofthe movable blanket cylinder and the bearings'of the plate cylinder cooperating withsaid movable blanket cylinder.

11. In a rotary olTset printing 'press, a perfecting unit comprising a pair of cooperating blanket cylinders between which the paper to beprinted passes, one :of said blanket cylinderstbeing'mounted in fixed bearings, the other being mounted-immovable bearings, a plate cylinder mounted in movable hearings on the side of said fixed blanket cylinder remote from said movable blanket cylinder, a hollow shaft to oneside of said unit, a second shaft mounted in said hollow shaft andprojecting beyond the extremity-of said hollow shaft, afirst lever keyedto said hollow shaft and a second lever keyed to said second shaft alongsidesaid first lever, means for locking said levers together in different angular positions comprising a self locking worm and wheel-connection carried by said levers, means for swinging said interlocked leversthrough a given angle and throwoif means extending from one of saidlevers' to andoperativ'ely connected with the movable bearings of said plate cylinder and from the other to and.

movable blanket-cylinder.

'12. In a rotary offset printing press, an impression cylinder; a blanket cylinder in printing relation with said impression "cylinder, a'plate cylinder 'disposedon the side of said blanket cylinder remote from, said impression cylinder, eccentrics in which said blanket and plate cylinders are rotatably 'mounted,' mean s' for operating the eccentric for said blanket cylinder to move it out of contact with the impression cylinder, said eccentrics having operatively connected with the movable bearings of-sa id operating arms carrying pivots, 'means'connecting said pivots and thereby said eccentrics yvhereby said plate cylinder eccentric operated upon operation I of said blanket cylinder eccentric, and means operating on said connecting means'to change the distance between said' pivots and"therebyfurtheroperate the plate cylinder eccentric to dense the plate'cylinder to' separate from the blanket cylinder' when the blanket cylinder is moved out'of contact with the impression cylinder;

13,.-,A,printing press as defined in claim,,12 wherein the meansconnecting said pivots comprises toggle links, and'said; distance changing means operates on the elbow joint of said toggle links.

14. A printing press as defined in claim 13 in which the eccentricities of said eccentrics and the lengths of the operating arms correspond, and wherein means operatively connected to the blanket cylinder eccentric and through it to the plate cylinder eccentric is provided for changing the pressure between the blanket and impression cylinders without disturbing the pressure relationship of the plate cylinder to the blanket cylinder.

15. In a rotary printing press, an impression cylinder, a blanket cylinder in printing relation with said impression cylinder, a plate cylinder disposed on the side of said blanket cylinder remote from said impression cylinder, eccentrics in which said blanket and plate cylinders are rotatably mounted, said eccentrics having the same eccentricity and being disposed at corresponding angles when the parts are in printing condition, throw arms of equal length on said eccentrics, connecting means between said arms, means for adjusting the blanket cylinder eccentric and with it the plate cylinder eccentric to change the printing pressure between said blanket and impression cylinders while leaving the'pressure between the blanket the elbow joint of said toggle connection when said i blanket cylinder is moved out of contact with said impression cylinder, whereby additional rotation is imparted to the plate cylinder eccentric to move it out of contact with the blanket cylinder.

17. In a rotary ofiset printing press, an impression cylinder, a blanket cylinder in printing relation with said impression cylinder, a plate cylinder disposed on the side of the blanket'cylinder remote from said impressiongcylinder, eccentrics .in which said blanket and plate cylinders arerotatably mounted, the ratio between the eccentricity and throw arm length of one eccentric being the same as the ratio of thecorresponding dimensions of ,theother eccentric, a lever mounted to turnupon a fixed axis disposed alongside said blanket cylinder, mechanism comprising a link connecting said lever and the eccentric for said blanket cylinder and comprising connecting means between said link and the eccentric for said plate cylinder, said mechanism being operative when said lever is turned in one direction to throw said blanket cylinder off from said impression cylinder and simultaneously to throw said plate cylinder ofi from said blanket cylinder.

18. In a rotary. offset, printing press, an impression cylinder, a blanket cylinder in printing relation with said impression cylinder, a plate cylinder disposed on the side of the blanket cylinder, remote from saidimpression cylinder, eccentrics in which said blanket and plate cylinders are rotatably mounted, said eccentrics having the same eccentricity and being disposed at corresponding angles when the parts are in printing condition, a lever mounted on a fixed pivot disposed alongside said blanket cylinder, a link connecting said lever and the eccentric for said blanket cylinder, a, toggle connection embodying toggle links between said first named link and the eccentric for said plate cylinder, said toggle links being aligned when the parts are inprinting condition, said first link being adapted when said lever is turned in one direction to impart rotation to said blanket cylinder'eccentric and through said toggle connection to impart a like rotation to said plate cylinder eccentric, and means connected with said lever for breakingsaid toggle connection when the lever is tnrned'as aforesaid to impart an added increment of rotation to said plate cylinder e'ccentricjwhereby said blanket cylinder is thrown otf from said impression cylinderand said plate'cylinder is :thrown 'ofi from said blanket cylinder. 1

19. I In a rotary offset printing press, a perfecting unit comprising a pair of cooperating blanket cylinders between which the paper tolbe, printed passes and a pair of plate cylinders cooperating :with said blanket cylinders, movable bearings for one only of said blanket cylinders and for both of said plate cylinders, that plate cylinder cooperating with the movable blanket cylinder being disposed on the side of said movable blanket cylinder remote from the immovable blanket cylinder, common means for moving the movable blanket cylinder and the plate cylinder remote therefrom through predetermined distances to break contact with the immovable blanket cylinder and for moving the .remaining plate cylinder in the same general direction as the movable blanket cylin-.

der through a greater distance to break contact between it and said movable blanket cylinder, and means for adjusting the pressure between said immovable and movable blanket cylinders while maintaining unaffected the pressure between said movable blanket cylinder and the plate cylinder cooperating therewith.

520. In 'a' rotary offset printing press, an impression cylinder, a blanket cylinder in printing relation with said impressioncylinder, a plate cylinder disposed on the side of said blanket cylinder remote from said impression cylinder, eccentrics in which said blanket and plate cylinders are rotatably mounted, said eccentrics having the same eccentricity and being disposed at corresponding angles, means for rotatably operating the eccentrics for said plate and blanket cylinders to move those'cylinders outwardly in the same general direction from the impression cylinder, said operating means comprising means imparting rotation of the plate-cylinder eccentric through a greater angle than that of the blanket cylinder-eccentric to cause separation of said plate cylinder from 'said blanket cylinder, and means for adjusting the plate and blanket cylinder eccentrics in unison throughthe same angle when the cylinders are in printing position whereby printing pressure between the blanket and impression cylinders may be changed without afiecting the pressure relationship between the plate and blanket cylinders.

1 References Cited in the file of thispatent France July 18, 1928