CA1208491A - Method of operating a printing press and apparatus - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

In a method of achieving rotary registration in a press having a helical gear-equipped central impression cylinder and a helical gear-equipped plate cylinder, the improvement characterized by orienting said plate cylinder year in a predetermined angular relation relative to a reference on said plate cylinder prior to installation on said press and, after installing said plate cylinder in said press, moving the said plate cylinder gear radially into engagement with the central impression cylinder gear.

Description

lZ(~ 9~ -......

MET~D OF~OPERATI~G A PRINTING P~ESS

1 BACKGROUND OF T~E INVENTION:
., ...~ .. __ ._,. _ This invention relates to a method of operating --a printing press and apparatus therefor and, m~re partic-ularly, to a press employing a central impression cylinder with a plurality of print decks disposed about the periphery ~hereof~
,~ .
~ ~ .
Illustrative of the art to ~hich the invention . ~V S
applies is co-owned patent 3,041/967. There the central impression cylinder receives ink impressions (generally ; lO different colors) ~rom six differe~t print decks, arranged ~2~

three on a side as is relatively commonplace in this phase of the printing artO Normaily, each deck includes a plate cylinder arranged to Lmpress a particular pa~tern ~n the wPb carriea by the impression cylinder. The ink, ~.e.r color, is ~ransferred to the plate cylinder which carries the plate embodying the desired pattern by means of a transfer cylinder, commonly re~erred to an "anilox roll". This ~ ..
~ anilox roll, in turn, deri~es the ink from a fountain roll operating in or in conjunction with a source of ink. Ihus, ~here is an arr~ngement of three rolls in each deck for developing the pattern or "repeat" as is commonly referred to in the art. The abo~e mentioned patent deals with a mechanism or bringing these various deck cylinders int~
contact so as to achieve the printing. This, howe~er, is a xelatively minor problem when compared with the problem faced by the art in changing the plate cylinders. It will be appreciated ~hat every time the "repeat" is to be changed, the plate cylinder itself has to be changed. The major problem that arises in this transition is that of achieving 20 register of thP various colors or patterns. Often, a large, expensive machine may be inoperative f~r an hour or two while the pressmen are adjusting the various decks to achieve registration.

.- The difficulty of achieving registration according ....
to contemporary technique can be appreciated from the follow-i~g typical sequence~ The ~irst step has been to install plate cylinders in all of the 6 decks~ These are nor~ally ~2~ 8L~

arranged three on a side with the ~irst deck being at the 10:30 o'clock position~ the second at 9 olclock, ~he ~hixd at 7:30 o'cl~ck, the fourth at 4:30 o'clock, the fi~h at 3:00 o'clock and the sixth at 1:30 o'clock. The sequence of achie~ing register normally starts with the No. 1 deck where ~he pressman hits two buttons to bring the plate cylindPr and the anilox roll almost into gear mesh. It will be appreciated that conYentionally the central impression .-- .
cylinder is equipped with a large gear usually called a lo "bull" gear which~n turn drives a gear ~rain for the plate and transfer cylindèrs in each deck~ these gears being arranged in tandem. Thus, the first step is to almost engage the anilox roll gear wi~h ~he place cylinder gear and the plate cylinder gear with the hull gear. To achieve gear meshing, ~he gear on the plate cylinder is "inched" in 5mall increments until proper mesh is achie~ed with the ~eeth on the bull gear. It also should be appreciated that these are helical gears -- necessitated ~or fine ad-ju~tment ~- so that gear too~h meshing is not readily 20 perceived visually. In the same fashion, the anilox roll gear is inched into me~hing relation with the plate cylinder gear. Thereafter, the rolls of the No. 1 deck are locked in position and inched into impression position. This is normally determined by inserting a 0.125" feeler gauge be~ween the surface of the plate cylinder and the surface of ~- ~he central impression cyli~der -- and this is required ... .
along bo~h sides of the web, i.e., at each end of ~he plate cylinder~ The same feeler gauge activity is performed on the ends of ~he anilox roll so as to bring it into proper ~2C~

1 impression position r Thereafter, a register mark is placed on ei~her ~he impression cylinder or web, as desired~ In s~me instances, both are employed because, although the regi.ster mark is much more visible o~ the w~b, it might slip rela~ive to ~he Lmpression cylinder.

The next sequence of steps in~olve indexing the t'~ impression cylin~er until the register mark lines up with the tangent point of the No. 2 plate cylinder relative to the central impression cylinder.

lo Nex~, the plate cylinder and anilox roll of the NoO

2 deck are brought into almost meshing relation an~ then inched into impression position utilizing the feeler gauge procedure described above. At this point, the plate cylinder is not locked to its gear so that the plate cylinder can be rotated until it is in register with the previously put down register mark, i,e., the pattern on the No. 2 deck plate cylinder is in congruence with the pattern pro~ided by the No. 1 deck plate cylinder.
Then the plate cylinder gear is locked relative to the plate cylinder. This same sequence of steps performed relative to the No. 2 print deck has to be performed with respect to the remaining print decks, i.e., decks

3 through 6 and it will be appreciated that at each stage, .- ~isual inspection o~ the printed pattern must be made to insure that each of ~he impressions provided ~y the six dec~s is in proper register. This has pro~ed to be time-consuming and wasteful of the producti~e capacity of large, high speed presses. This is particularly _ 4 _ '~2~

true when short "runs" are made because the changeover from one run to another requires going through the laborious changeover procedure just described.

~he obvious solution to the laborious registration procedure is ~o provide register marks on the central impression and plate cylinders befoxehand corresponding . ....
to a yi~en repeat. Howe~er, this has not proven successful in practice probably becausP of the difficulty of utilizing the large number~3f marks necessary to cover the spectrum of "repeats". Also, the gear teeth are relatively small and because it is diffîcult to discern misalignment of the order of a quarter or half degree, very often the wrong gear teeth are engaged. In this connection, it should be appreciated that the gearing is helical rather than con~entional spur gears which further complicates the problem of making sure that the right gear tooth is selected for engagement with the correct "valley" in the mating gear so as to bring the proposed register marks into alignment. The aligned register mark expedient was suggested in French Patent i6 26719 but to the best of applicant's knowledge, this has not been adopted in practice. The teaching of the French patent is ~hat the register marks on the plate cylinder and central Lmpression cylinder should be in line after the gear teeth have been brought into engagement. This really ~ does not address the problem because it is difficult ~o know which helical tooth should be selected beforehand so as to bring about the alignment after the helical teeth have meshed.

~z~g3 . SUMMARY OF INVENT~ON:

The inventio~ solves the foregoing problem by srienting the plate cylinder gear to a predetermined orie~t-ation and while the same is "off" the machine. This elimi~ates the substantial "down kime" that is characteristic of contemp~rary practice while registration is sought and f--t.-. also provides a regulated or controlled a~mosphere in which the adjustment or orientation can be made. Further, it can be done with ~ch exactitude tha~ when the plate cylinder gear is mounted on the plate cylinder, the plate cylind~r gear can be brought into meshing rPlation with the bull gear by linear movement of the print deck only and without the disturhing an~ uncontrolled axial movement proposed in other expedients, as in the above-identified French patent.

More particularly, the in~entive method utilizes a register assembly incl~ding sleeve and collar means and gearing which can be adjusted relative to each other off-machine and to a predetermined position on the plate 20 ~ylinder journal or shaft so that when the regist~r assembly is mounted on the plate cylinder journal, th~ plate cylinder not only has exact gear tooth engageme~
but also and, most importantly, proper registration. Here it ... should be appreciated that there is always l'fine tuning" of the ;.. . .
registration after the press has started operating by virtue of minor adju tments of the rotary positions of the ~arious plate cylinders made possible by means of axially sliding the helical gears one relati~e to another.
This is where the artistry of the pressman comes into 30 pIay so that ~he desired registration need only be such as to permit the pressman to ~inish the regi~tration procedure by a minor ~hift of the various helical gears.

~2~8~

The invention i5 explained in conj~nction with ~he accompanying drawing, in which --FIG. 1 is a side elevational ~iew somew~atschematic of a six color flexographic press such as would be employed in the practice of the in~ention;

.. FIG. 2 is a fragmentary side elevational ~iew in partial section showing the plate cylinder mounting assembly and rema~nder of mechanism employed for deck positioning;

o FIG. 3 is a side elevational view partially in section and partially in phantom line of the plate cylinder, register assembly and associated press components;

FIG. 4 is a perspecti~e view o~ the register - assembly;

FIG. 5 is a perspective view of the set-up fixture for the register a~sembly;

FIGS. 6-8 are perspective views of the register assembly components;

FIG. 9 is a fragmentary side elevational view 20 of a portion of the bull gear and associated proximity swi~ches for accurately positioning the bull gear;
... .
FIG. 10 is a top plan ~iew of the proximity switches of FIG. 9,o 9~

IGS. 11-~4 are schematic side eleYational views of ~he gearing involved for di~ferent repeats on the plate cylinders;

FIGS. 15 and 16 are, respectively, side and end ele~ational view~ of the portion of the print deck dealing with the anilox or transfer rs~l~
~...-.
-- FIG. 17 i~ a perspective ~iew of a device used in the setup of the machine; and FIG. 18 is a s~hematic view havin~ certain symbols applied thereto employed in computations for achieving registration.

DETAILED DESCRIPTION OF THE INVEN~ION:

~ he central impression printing secti~ 20 of ~IGo 1 is typically arranged with six printing decks 21 and 21a ~hrough 21e arranged symmetrically about the central impression cylinder 22. The apparatus is supported on a conventional fxame F. An incoming web 23 is placed on ~he surface of, and remains in intLmate contact with the surf ce of the central impression cylinder 22 as it rotates past the six color decks 21-21e and finally exits a~ at 24~ Between color dryers are o~ten used (for example between color decks 21 and 21a, etc.) ~ut are not shown for purposes of clarity.
,_.
'~- Each color deck assembly is compris~d of like elements including plate roll cylinders 25 each mounted on a movabIe sub frame 26 which supports a bracket 27. The bracket ~7 is independently movable from sub frame 26 and supports an anilox rsll 28 and a fountain roll 29. Each frame 27 also supports an ink fountain (not shown) mounted directly below each fountain roll 29~ Further details on ~he individual deck construction are shown in FIG. 2. Inasmuch as each color deck embodies the same elements, each element ha~ been given 2~

the same numeral. Where a distinction is required between the elements of different decks, the numeral will be suffixed by the appropriate letter -- as for example the plate roll cylinder o~ deck 21b (at the 7:30 o'clock position in FIG.
1) is design~ted 25b.

f.~:................. Each sub~frame 26 and hence its associated bracket ; .-27 is mounted on frame ext~nsion 30 and is mov~ble relati~ethereto~ In the first printing deck 21, this movement will be along line 31 and`, the other decks along counterpart lo lines -- ~or examplel line 31c for deck 21c.

The operation and mechanism associated with the linear mov~ment of the ~arious deck cy~inders into impression position will be described hereinafter and with respect to FIG. 20 Turning now ~o FI~. 3, a sectional view in fra~mentary form of the plate cylinder 25 is seen along with the associated mechanism for operating ~he same.

The plate cylinder 25 has a journ~l or stub shaft 32 formed integrally therewith and which is normally employed ~or carrying the gearing which rotates the plate cylinder 20 in synchronism with the centxal impression cylinder 22. For example, the numeral 33 designates the helical gear associated with the plate cylinder 25 while the numeral 34 designa.es ....
a portion of the bull gear fixed to the ce~tral impre~sion cylinder 22. Shown in dotted line and designa~ed 33' and 34' are another pair of gears associated, respectively, with the plate cylinder and central impression cylinder for a slightly differe~t operation. Conventionally, flexographic presses are equipped with 10 pitch (diametral) gears and one quarter pitch circular gears. The gears are not 1 too differe~t but make for a different type ~f repeat operation as is conventivnal in the art.

Interp~sed between the journal 32 and the bull gear 34 and carrying the plate cylinder gear 33 is a register assembly g~nerally designated 35. This is rem~ably mounted on ~he journal 32 and can be arranged in a desired condi~ion or configuration away from the machine so as to .. - *
ma~erially speed up ~he changeo~er or set up time ~or a different repeat. For example, the color-t~-color o registration procedùre currently employed often involves from 15 to 30 minutes per color. With from approximately 1-1/2 to 3 houxs or more of set-up time and lost production involved in the state of the art set-up time, the inventive procedure can su~stantially increase press up-time by allowing off-ma~hine s tup while the press is opera~ing.

The register assembly 35 ineludes a number of elements cross hatched in FIG. 3 and which are essentially concentrically related to each other. Innermost is a sleeve 36 which is slidably mounted on the journal 32 20 and which is equipped with an external spline as at 37 --see also the right hand portion of FIG, 4.

FIG. 4 depicts a perspective somewhat exploded version of the register assembly 35 and he j~urnal 32 -- the latter bein~ seen in fraymentAry form at the extreme :
left hand portion of FIG. 4. FIG. 4 is concerned primarily with the left hand end portion of the register assembly and hence the gears and certain of the concentric elements are omittea there~rom, . Returning now to FIG~ 3, the n~eral 3~ indica~es 30 a second sleeve and which is e~uipped wikh an internal spline so as to mate with the external spline 37 on the firs~ mentioned sleeve 36.- Thus, movemen-t of the slee~e 3B
relative to the sleeve 36 is constrained to ~he axial direction and is employed when the ma~hine is set-up for the purpose of making fine adjustments in register. For example~ the registrati~n employed by the inventive method ce~ters the gear 33 axially within the gear 34. Sliding movement of the collar _ _ 38 relative to the collar 36 moves the gear 33 to the right or left, as ~he case may be -- and because the gears 33 and o 34 are helical g~ars -- will result in a slight rotation of the plate cylinder 25 relative to the ce~tral impression ~ylinder 22 (because the latter has the bull gear 34 affixed thereto and there is no relative rotational movement between the gears 33 and 34). The gear 33 ~an be seen to be removably mounted on the collar 38 by means of the bolts 39.

The specific objec~ of the invention is to orient the register asembly, particularly the gear 33 relative to a reference poin~ off the machine that will 20 permit the register assembly 35 to be installed relative to a similar reference point on the plate cylinder and ~hus have a preselected tooth on the gear 33 enter a preselected valley between teeth on the bull gear 34.
As indicated pxe~iously, this is ~irtually impossible . to do visually on the machine as by aligning reference points such as ~cribe lines on the plate and central impressio~ cylinders or the gears associated therewith.
The gears are relati~ely fine toothed and, in this instance, the teeth are helical a~ong an 18 degree an~le which 30 makes matching visually virtually impossible.. The discussion immediatel~ following deals wi~h the orientation of the register assembly 35 so as to have the p~opex too~h ~z~

on ~he gear 33 in position f~r exact engagement with a predetermined valley between t~eth on the bull gear 34.
Subsequently, the steps employed for properly l~cating the bull gear will be discussed.

With reference to the proper positioning of the plate cylinder and its regi ter assembly 35, it first sh~uld -= bP appreciated that the plate cylinder is equipped with a plate 40 (see FIG. 3) which is precisely positioned on the plate cylinder r~ ative to an imaginary scribP line. In the in-~o stant case, the scribe line can be considered the line 41 (see the left hand portion of FIG. 4) which bisects the ke~ay 42 in the shoulder of journal 32. The keyway is also seen in the central left hand portion of FIG. 3. The object, as expressed somewhat differently above, is to locate the precise tooth needed for pattern registration in exact alignment with the Lmaginary scribe line 41, i.e., the ke~way 42. More precisely, it i~ desired to have the center of mid-point of the helical tooth so aligned 50 as to permit the fine ad~ustment previously referred to. The ma~ter of the orientation of ~he 2~ plate cylinder gearing is further complicated by the fact that the various decks 21-21e have different angular relationships to the center of the central impression cylinder 22 so that a phase difference exists between ~e various decks.
Inasmuch as the ultimate object is to have the various cylinders of the various decks oriented properly so that .
they all can be substantially simultaneously brought into printi~g engagement, provision must be made for this phase differen~ial. Before goin~ into that, however, it is believed helpful to the understanding of the invention to discuss the No. ~ deck, i.e., ~Deck 21-a where the phase angle can be considered zero. It will be appreciated that with respect ~o this deck, the line of mo~emen~ along line 31a (see FIG. 1 -- the center lef~ hand portion) passes through the eenter of the central impression cylinder 22.
...... .
-- To orient the register assembly 35 associated wit~h the plate cylinder of each deck, ~he elements at the left hand portion ~f~ the register assembly 35 as seen in FIGS. 3 and 4 are used in conjunction with a set-up ~ixture seen i~ FIG. 5. The set-up fixture is generally designated 43 and can be see~ in various aspects in FIGS. 6-8 as well.

The fixture 43 includes a base 44 (see particularly FIG. 6) and mounted thereon a pedestal 45. The pedestal is equipped with a bearing ~not shown) which support~ a du~my or stub shaft 32' correspondins to the plate cylinder shaft 32 and which is equipped with a similar keyway 42' -- facing downwardly in FIG. 6~ Removably mounted on the shaft 32' is the register assembly 35.

Referring now to FIG. 7 which is a perspective view of the fixture 43 but from the opposite side from that seen in FIG. 6~ and with cover removed, the numPral 46 designates ,- a pair of brackets interposed between the base 44 and the pedestal 45 for the purpose of supporting mechanism to turn the shaft 32lo For ~his purpose9 the shaft 32' is equipped with a WQrm gear 47 which cooperates wi~h a worm 48 carried on worm shaft 49. The shaft at the right hand end (as seen in FIG. 7) is e~uipped with a hand wheel 50 so that upon tu~ning the hand wheel the worm and wonm gear cooperate and 13 ~

rotate the shaft 32' and hence the register asse~bly 35.

At the left hand end (as seen in FIG. 7~ the worm shaft 49 is equipped with a co~lter drive geax Sl which is in meshing engagement with a counter driven gear 52. The gear 52 is provided as part of a counter assembly 53 mounted . on o~e of t~e brackets 46. Thus, the angular rotation o A-'.' .. the stub shaft 32' is reflected ln the digital counter 53.

In the operation of the fixture 43, the digital counter 53 is set at zero~nd i~ this condition the hand whe 1 53 is lo oriented so as ~o position the ~eyway 42' o~ the shaft 32' in the downwardly facing position. Thereafter, the register assembly 35 is slid onto the shaft 32' by sliding the sleeve 36 axially of the shaft and with th2 pin 54 of the collar 55 (see FIG. 3) generally aligned with the keyway 42'. Reference to the left central portion of FIG.
3 reveals that the sleeve 36 at the end adjacent the pl~te cylinder 25 rotatably carries the collar 55 which in turn is equipped with the pin 54. This can be appreciated more readily from a consideration of FIG. 4 where the O sieeve 36 is seen to be equipped with a radial enlargement 56. It is this enlargement which rotatably supports the collar 55. The pin 54 extends through the radial enlargement 56 so as to enter the keyway 4~' and for this purpose, ,...... the radial enlargement 56 is e~uipped wi~h an arcuate slot ... _. , 57 (see the central part of FIG. 4).

After the register assembly 35 has been ensleeved on the stub shaft 32', and with the pin 54 ~xtending into the keyway 42', exact posikioning of a preselected tooth of the gear 33 is undertaken. What is meant b~ the center of the .
: ~ 14

4~
;

tooth can be appreciated from the upper central portion of FIGn 3 wh~re ~he center of a particular to~h T is desig~ated T~. The object of ~his phase of the inven~ive method is to orien~ ~he center Tc of a particular tooth T in exact alignment with the imaginary scribe line 41 so that upon translation,of the plate cylinder 25a toward the central Lmpression cylinder 22 (see the right central portion of ~ -~- F~G. 1), the gear ~eeth of the bull gear and plate cylindex gears will mesh precisely.
.
..
lo For ~hat purpose, the fixture 43 is equipp~d with a gauging block assembly generally designated 60.
More particularly, a pair of gauging blocks 61 and 61' are provided for use with the two gears 33 and 33' ---only one of which is used in a particular installation.
It will be appreciated tha~ the central impression cylinder 22 is equipped wi~h a pair of bull gears having different tooth configurations as mentioned previously and when one bull gear as at 34 is chosen for the operation of the press, the plate ~ylinder gear 33 is empl~yed and 20 ,this is gauged by the g~uging block 61.

The gauging block 61 is mounted on the assembly 60 f or vertical movement through a gear train and linkage system (not shown) but which is operated by the second hand _..
wheel 6c (see the upper portions of FIGS. 6 and 7). As the gauging block 61 is elevated by turning the second hand wheel 62, the gear-33 is ~',ockeyed~' into precise position between the positioning struts 63 and 64 of the gauge blocks 61. This is permitted in ~he register assembly 35 by virtue of the arcuate'slot 57 (see the central part of FIGo 4}. More particularly, the gear 33 (see ~IG. 3) is fixedly related to the sleeve 36 by virtue o~ ~he splin d ~z~g~
1 interconnection between the sleeve 3B carrying the gear 33 and the sleeve 36. On the other hand, ~he collar 55 is ~ixed in position by virtue of the pin 54 thereof being confined in the keyway 42'. Slight angular movement of the gear 33 by virtue of the slot 57 in the sleeve 36 is possible so that during the upward movement of the gauge block ~ S i~ /f a~t eCJC~S/~/
_ ~ 61, ~he tooth T can be -Q~ul~-~ne~ engaged by the struts !:..
- 63 and ~4 until the block 61 moves to the end o~ its upward travel -- at which time the struts 63 and 64 are fully lo seated in the ~alleys~flanking the tooth ~r. At this stage, the center T~ of the tooth T is precisely aligned with the imaginary scribe line 41. Thereafter, the lock bolt 65 (see FIG. 4) o~ the collar 55 is tightened so as to clamp ~he collar 55 immovably on the radial enlargement 56 of the slee~e 36. This is achieved by virtue of the collar 55 being split as at 55' (see the central part of ~IG. 4~.

As indicated pre~iously, if tne register assembly 35 is the one to be installed on the second deck plate cylinder 20 25a, no further manipulations would be required. However, this is not true for the plate cylinders of the remaining decks which have different phasing. This can be best appreciated from a reference to FIG. 1.

--- In FIG. l, and relative to the second deck, i.e., ~-the deck 21a, the point of tangency 66 is seen to lie on the line of deck movement 31a -- the point of tangency 66 being ~he impression point between the plate cylinder 25a and the central impression cylinder 22. However, the situation is different as exemplified by the third deck 21~. There the 3~
point of tangency 67 is angularly offset from the line of deck movement 31b and to insure that a particular too~h on the plate cylinder gear falls between tee~h of the bull gea~ 34, the plate cylinder must be rotated out of alignment with the scribe iine 41. If it were not, it w~uld be translated along the line of deck movemen~ 31b and thus not mate with the associated ~alley between teeth of the bull gear. The -- needed rotation can be precisely determi~ed trigonometrically.
One of the factsrs requiring the r~tational adjustment of the gear 33 is the fact that the line of movement 31b of the third deck is at l5~degrees to the horizontal and, as is clearly apparent from FIG. 1, does not pass through the centex of r~tation of the central impression cylinder 22.

An additiona7 complication arises because of the non-alignment of the centers of the plate cylinder 25b and the center of the central impression cylinder 22~ This means that as the tee~h of the gears of these respective cylinders engage, ~here is an additional slight angular rotation o~ the plate cylinder between engagement and full 20 seating -- of the order of about 1 1/2 degrees. Again, ~his can be calculated with precision beforehand. Thus, from ~he geometry and using trigonometric functions, ~he precise angular rotation or "phasing" of the gear associated with the plate cylinder 25b can be predetermined and this - is introduced into the setup fixture 43 by turning the hand ~ ....
wheel 50 so that the digital counter 53 reflects ~he precise angular phasing desired. More particularly, wi~h collar 55 clamped onto the sleeve 36, the gauge block 61 is ele~ated to its up position so as to engage 30 the tooth T. Then the hand wh~el 50 is turned to rotate the register assembly 35 to the orie~tation desired as refleeted by the counter 53. The particular tooth T needed ~Z138~9~

to be positioned at the point o~ tangency 67 is now in that position and I provide a locking collar with detent means for maintaining that position before the register assem~ly is remoYed from the ~ix~ure 43 and installed on the shaf~
32 of the particular plate cylinder involved, ~ eferring now to FIG. 3, the register assembly at its righ~ hand end is seen to ~e equipped with a further ; .
~ ....
coll~r 68 which is rotatably mounted on ~he sleeve 38. me collar 68 is equipped wi~h a detent 6~ (see the bottom right o hand portion of F~G~. 3) which can be rotated into alignment and engagement with the rounded end of the plunger shaft 70 (see FIG. 6). A plunger de~ice 71 is pivotally mounted on the ba~e 44 and is swung into position in general alignment with the detent 69 and as the collar 68 is rotated ~he "ball" end of the shaft enters the detent 69. A portion of the collar 68 is split and equipped with a lock bolt 72 (see also the right hand end of the FIG. 3) which is tightened so as to clamp the collar 68 fixedly to the sleeve 38. I ha~e thus provided a reference detent to orient the particular tooth T (as well as coincident key 42 and imaginary line 41) in a predetermined angular position relative to the detent.

A similarly constructed pl~nger is pro~ided on the frame F for each deck 21, 21a, etc. This plunger is indicated .. -:.: :. .
-sohematically by an arrow 73 in the upper right hand portion of FIG, 2 and relative to the first dec~ 21. Thu~, for each pla~e cylinder of each deck, the fixed plunger device associated with each deck is used to hold detent 69 in a reference position so that scribe line 41, key 42 and a particular tooth T

1 2~1 34gl 1 are in the proper angular relationship relative to the detent 69 engaged at the reference 73. Thereafter, the plate cylinder equipped with ~he register assembly 35 (preset to the s~me predetermined angle) is installed in the subframe 26 ~nd rotated until the "ball" of the frame plunger reference 73 engages the detent 69. After the teeth of the gears 33 and 34 h~ve become fully engaged, the plunger device is then activated ~ut of engagement with the detent 69 ~- by cylinder 115.

. lo Exact g~ar mesh and regis~ration (subject to the small fine tunin~ by the pressman during actual operation) is thus provided by the inventive method. The plate 40 of the plate cylinder 25 (see FIG. 3) is preci~ely positioned on the plate cylinder scribe line 41 (see FIG. 4). The register ass~mbly 3; is also precisely posikioned relative to the scribe line 41 by virtue of the pin 54 (see FIG. 4 entering the keyway 42 associated with the journal of the pla~e cylinder. After the pin 54 has been seated within the ~eyway 42, a ~urther collar 74 (see FIG~ 4) is tightened 20 to hold the assembly on the plate cylinder journal. The çollar 74 is a split collar as at 75 (see FIG. 4) and is equipped with a lvck nut 76. This is lo~sely mounted on the extreme left hand or inner end of ~he sleeve 36. The sleeve 36 has slotted cutouts as at 77 so that when the lock nut 76 of collar 74 is tightened, collar 74 clamps the slotted ...~.... .
end of sle~e 36 to journal 32~ Thus, the register assembly a~d most importantly, gear 33~coincident key 42 and scrih~
line 41 are in a fixea angular relation to ~he plate 40 of the plate cylinder 25. Wi~h the particular too~h T and 30 coincident scribe line 41 in a pr~determined angular relation to the frame ref rence 73~ ~he plate cylind~r can be translated . .
- 19 - .

1 along the line of movement 31, 31a, etc., to bring about engagement of preselected teeth of coacting central impression cylinder and plate cylinder gears with proper orientation of each plat~ cylinder to achieve registrati~n between all de ::3cs .

Exemplary of the variety of repeats utilized in . f lexographic printing are the showings of FIGS. 11-14. In ......
all of ~he four views, the bull gear 34 (see ~IG. 11) is a ten diametral pi~ch ~00 tooth gear. The plate cylinder lo gears are for differènt repeats and are in the position they would occupy in the third deck, viz., deck 21b where the line o mo~ement has been designated 31b. The examples of FIGS. 11-14 represeni the actual installation where the detent 69 has been oriented at 90 degrees to the line of movement 31b. Locating the plunger device 73 at the bottom of the regîstex assembly 35 ra~her than obtusely relative to its line of movement is a matter of design choice and con-venience for deck 21b.

Thus, in set-up znd subsequent plate cylinder 20 lnstallation, the gear tooth T, keyway 42, and scribe line 41 will be angularly rotated relative to reference 73, said rotation taking into account differences in angular positions of 73, 73a, 73b, etc., as well as the difference in the point .. -.. -. of tangency 66-67, etc., and most importantly, the dif~eren~e ~-in repeat l~ngths effecti~e between decks. The predetermined angle includes these~ e-di~ferences when the angle is registered on counter 53.
To illustrate the difference in detent position for different repeats, the following table lists various values:

.

~Zl38~91 T~BLE

No. of Pitch Leng~h of Angular F~Go ~O_ Teeth _Diameter Repeat Displa_ement 11 11~1 11~490 35~814 8~528 12 lOt~ 10~000 31~16 48~02 13 76 7~600 23~876 149~700 14 39 3~900 12~252 192~409 .
Two other orientations are performed on-m~chine prior to engagement of ~he ~arious decks with the central Impression c~linder 2~ One~as ~o do with the positioning of the bull gear 34 and the other has to do wi~h the positioning of the transfer or anilox rolls 28. To better understand how these orientations fit into the overall operation, ~he structure and operation of ~ typical deck will now be explained with refere~ce to deck 21 as depicted in ~IG. 2.

As indicat~d previously, each deck su~h as the first deck 21 includes a plate cylinder 25 which bears against the cylinder 22 as wall as the transfer or anilox roll 28, ountain roll 29, subframe 26 and bracket or secondary sub-~rame 27.

An i~k fountain (not shown) is mounted directly below rubber covered fountain roll 29 which simply picks up a full coating of ink for transfer to the anilox roll 28. Pneumati~
cushion 78 variably urges independently driven roll 29 int~

.......
contact with roll 28. In the print deck being described, :.
secondary frame 27 housed within guides 7~ can be slidably urged toward stop 80 by action of cylinder 81 through a linkage indicated in dotted line. Secondary frame 27 can be moved independent of sub-frame 26 for the purpose of disengaging 30 ro~l 28 from nipping contact with roll 25 and thus, when stopping a pres5 run, roll 25 will continue to print until it purges itself of ink. A~ter some delay, sub-frame :~2~)84~

26 housed within suides 82 can be slidably urged toward stop 83 by action of cylinder 84 through the linkage sho7~n.
~ovement of sub-frame 26 and secondary ~ub-frame 27 thu~ pulls the whole complement of rolls from contact wi~h the su~
strate W lying on the surface of cylinder 22 and hence printing stops.
,.. - .
........
A rotatable collar 85 on screw thread 86 can be positioned such that a gap 87 establishes the amount of - mo~eme~t effec~ed ~ action of cylinder 81 through its lo linkage. Likewise, collar 88 on screw thread 89 establishe~
a gap 90 which defi~es ~he movement of s~b-frame 26 by action of cylinder 84 through its linkage.

When the secondary frame 27 is moved outw~rd until collar 85 i~ in contact with stop 87, it defines a rearward position whch is used as a re~erence for positionin~ the anilox roll ~8. When subframe 26 moves outward until collar 88 contacts stop 83, its outward position likewise defines a reference from which inward movement can be measured, and in this instance, refers to a plate roll positionin~
20 reference.

Since the threads per inch on screw thread 86 and the gear ratio between worm gear 91 and worm 92, etc. are ~-......... all determinate, th~ specific anyular rotation of motor 93 will produce a known and measurable inward movement of ~econdary frame 27.

In like manner, fo~ard mo~ement of sub-frame 26 can be measured and controlled by mot~r 94. Motors g3 and Cc~ ~" f~ à~
99 are digitally controlled, and by use ofldigit counters (not shown), the k~own position of secondary frame 27 and therefore roll 28, a~ well as sub-frame 26 and roll 25 can be defined.

In like manner, knowing the distance between a given reference point and the center line of the plate roll 25, sub-frame 26 must move inwardly a specific distance from the reference point to be in nipped impression.

It will be noted that full inward motion to achieve impression cannot be achieved unless the gear tee~h of year~ 33 and 34 properly mesh and hence, deck positionLng ...... .
to full impression is a beneficial but a dependent function of proper gear me~h.

o Before describing FIGS, 9 and 10, reference is made to FIG. 1/ deck 21a which moves along line 31a. For l/c ~/e~
initial setup of the ~oo~h (and ~e~e~) sensing detector, a fixture f (see FIG. 17) ha~i~g a horizontally extending pin P is attached to the journal of plate cylinder 25a and extends inwardly toward the central axis of the central impression cylinder. The tip of the pin P is shaped in gear profile and when positioned inwardly, falls at position 66 of deck 21a. If ~he pin P seats properly in a valley between two teeth of the bull gear, no further adjustment of positioning of the sensing devic~ is required however, if the gear profiled pin does not seat properly, ~he sensor can be positioned and calibrated until proper meshing relationships occur as described hereinbelow.

~~ The firs~ of ~wo required on-machine alignments, that is, positioning of the bull gear to receive a prepositioned too~h of the plate roll cylinder gearing, is accomplished by using the mechanisms in F}GS. 9 and 10. There, the frame F supports a horizontal shaft 94 mountPd in support 95 (seen only in 2~ 8~

FIG. 10~. ~his ex~ends axially of the two bull gears 34 and 34' and c~rries brackets 96, 96' for the proximity swi~ches 97, 97' -- one for each gear.

Brackets 96, 961 holding proximity switches 37, 97' can be rotated with respect to shaft 94 and can be slidably . posi~ioned along shaft 94 so that the sensors 98, 98' f~s of the switches 97, 97' li~e up with the center of the bull ~.. ..
sears 34, 34'. Brackets 96, 96' are rotated so that a small air gap exists between sensors 98, 98' and the bull gears.
lo When energized, the~`sensors will detect diferences between a metallic gear tooth and the adjacent void (valley) and in this manner r they describe th~ edge of a gear tooth on ~he bull gear.

Initially, if the gauging pin, as at position 66 in FIG. ~ i~ not centered with a valley of the bull gear tooth,axial mo~ement (left or right in FIG. ~0) of the proximity mounting brackets 96 or 96' will cause either sensor 98 or 98' to s~nse either the presen~e of metal (top of gear too~h), or the absence of metal (valley between gear teeth).
20 Detecting and diffexentiating between metal or voidl this signal can be used to dri~e the bull gear in one direction or the o~her until the gauging pin at position 66 of FIG.
fits directly into a valley between ~wo gear teeth of the ~-. . bull gear.
~. -. . .
In FI&. 10, it will be noted that either one or bo~h of the brackets 96, 96' can be moved axially~ Since ~he bull gear teeth are helical, axial movement of the bracket and associated sensor results in delivery of an electrical error signal to a hydraulic motor H (see FIG. 1) .

~z~

which moves the bull gear 34 very slowly until the error signal ceases. In this mannex and by moving -the sen~ors.
a small amoun~, a valley between ~wo gear tee~h can be accurately aligned with the plate cylinder gaugi~g pin ~not shown) at position 66 of FIG. 1. WheIl a valley is accurately aligned with the gauging pin, brackets 96, 96' are lockably _ clamped ~o shaft 94 and remain fixed in this positi~n without t.:::.
~ furth r need for adjustment.

Thus, a~er initial setup, ~he sensors will always ~g e"e,~, f e ~
10 gcn~rn~ an elec~rical error signal until detection of a tooth edge at the position shown in ~IG. 10 results in placement of a ~alley between teeth in alignment with the gauging pin at position 6 6 of ~IG . 1. It is noted that the valley between any two teeth of the bull gear establishes the necessary precondition for proper gear mesh between the bull gear and a plate cylinder gear t~oth -- the plate cylinder gear tooth being positioned to engage horizontally, as at 66 in FIG. 1. This is a reference position for the bull gear since deck 21a is used as a reference from which other angular 20 deviations are measured. In other words, once the sensor bracket is tightened a~d a valley between bull gear teeth is precisel~ aligned for gear mesh, calculating the angles for other decks will automatically take care of differences ..... in line of mo~ement relative to the axis of the central .
impressio~ cylinder, etc.

The second of two on-machine orientations required prior to gear engagement is that of the anilox roll gears and this will be explained in ~onjunction wi~h FIGS. 15 an~ 16. ~n 30 FIG. 16 the anilox roll is seen in a very small ragment at the extreme right hand end and is designated 28. It also is equipped with a journal as at 99 supported in a 349~

1 bearing generally designated 100 and provided as part of the secondary subframe 27~ The journal extends beyond ~he bearing 100 c~rries a pair of gears 101 and 101' for meshing engagement with the plate cylinder gears 33 or 33', respecti~ely. Again, these are helical gears and even though ~here is not the problem of register for the anilox roll 28 - it can be in any orientation to transfer ink to the -plate cylinder 2~ -- there is still the pro~lem of achieving proper gear mesh. ~The object, of course, is to reduce the lQ engagement of the various cylinders to a simple lineal motion achieved by the operation of the fluid cylinders 84 and 81 (see the bottom left hand portion of FIG. 2).

Again wi~h th~ geometry of the plate cylinder gear 33 being kn~wn, it is a straightforward trigonometric calculation to determine what the orientation of the anilox roll gear 101 should be for smooth meshing. Thus, for each repeat, there is a predetermined angular orientation of the anilox roll gear 101 which must be introduced into the system.

For the purpose of properly aligning the gear 101 with the gear 33, I provide a dial 102 which is affixed to the gears 101 and 101'. More particularly (here referring to the 1 ft hand portion of FIG. 16~, the dial 102 consists of a plate carrying on its outer face numerals indicating .:.-~- degrees. The plate is bolted to a tubular member 103 which in turn is bolted to the gear support 104.

Although any gear tooth can be selected for proper mating engagement wi~h the plate cylinder gear 33~ I prefer to select a tooth which can be oriented an integral number of degrees from an indicator mark 105 at the extreme top of . 30 FIG. 15. The indicator mark 105 is carried on a split , ~ _ 4~

collar 106 which is rotatably mounted on the member 103.
If, for example, a given repeat requires that a tooth be selected for engagement which is 13 deyrees di~ferent fxom exact alignment of the indicator mark 105 and the zero degree dial setting, the transfer cylinder 28 is rotated until ~he dial setting is 13 degrees -- as determined visually rela~ive to the'indicator mark 105.

,... .
','',,- If the roll is angularly positioned such that zero re ding on the dial is aligned wi~h indicator mark 105 when ball 109 is engage~,in the detent 110l then angular rotation of the roll (and dial) to the predetermined angle will position a gear ~ooth at the same predetermined angle from the detent and, therefore place it in the proper angular =~dhi~ for gear engagement between transfer and plate roll gears. In ac~ual operation, I provide a card for each repeat cylinder listing the anilox roll angle setting.

Operation In the operation of the invention, those responsible 'Y~f seJ of for plate mounting are ~h~x~ a forthcoming change in repeat.
~e .~
~ thereupon select the si~ appropriate plate cylinders -- this while the press is operating on a previously selected repeat --and install extra register assemblies 35 on stub shaft 32' of fixture 43 for proper orientation away from the machine.
r.-.-'.-'..'.'.. . More particulaxly, the lock bolts 65 and 76 of the collars t . . , 55 and 74 respectively (see FIG. 4) and ~he lock bolt 72 of th collar 68 t'~ee FIG. 6) are loosened 50 as to be freely rotatable. Register assembly 35 was ensleeved on the stub shaft 321 (see FIG. 5) with the pin 54 (compare F~GS~
3 and 4) in ali~nment with the keyway 42' (see FIG. 6). The keyway 42' is identical wi~h the keyway 42 seen in ~he left - 27 ~

hand portion of FIG. 4 and a~sociated wi~h the plate cylinder 25. This results in a preselec~ed, part;cular too~h T of the gear 33 (see FIGS. 3 and 6) being in general alignment with the keyway 42' -- and more specifically the imaginary scribe line 41 bisecting ~he keyways 42 and ~2'.

To insure exact positioning of the preselected tooth so ~hat its center Tc (see FIG. 3) will be centered axially ~. .
of the bull gear 34 (or 34'), the hand wheel 62 i5 turned to eleYate the gauging block 61. As the gauging block 61 lo or 61' (see FIG. 5) ~is being elevated slowly, the gear 33 is minipulated or "jockeyed n SO as to have the particular too~h T positioned squar~ly between the struts 63 and 64 (see ~ 8). This is made possible by virtue of the ~act that the sleeve 36 -- the innermost part of the register assembly 35 and whieh carries the gear 33 -- ls equipped wi~h a slot 57 through which the pin 5~ extends --again see FIG. 3. When the struts 63 and 64 are at the very base of the valleys flanking the selected tooth T, ~he tooth T is properly centered and the lock bolt 65 is 20 tightened so as to fix the collar 55 (still refexring to FIG. 43 firmly in place on ~he sleeve 36. The preselected tooth T now has its center in exact alignment with the imaginary ~cribe line 41.

. The reyister assemblies 35 for all plate cylinders , .......
..
except 25a associated wi~h No. 2 Deck have to have a pre-determined phase angle introduced thereint~. This stems from the difference in an~ular orientation of the decks as explained previously. ~or example, the first, third, fourth and sixth decks are so arranged that ~he line 30 of movement of th rolls thereon does not pass ~hrough ~be .

point of tangency wi~h the central impression cylinder 22 so a phase angle has to be introduced to make sure that the prsper tooth on the gear 33 enters th~ proper ~alley of the bull gear 34.

T~ introduce this preselected angle, the gauying blocks 61, ~l' are retr~cted so as to free the geax 33 for ;-.. -~....... rotation. ~ere it will be appreciated that the register assembly 35 cannot rotate relati~e to the stub shaft 32' because o~ the engayement of the pin 54 with the keyway 42l.
And, wi~h the oollar 55 firmly clamped to ~he sleeve 36, there is no relative rotational movement between the pin 54 and the gear 33.

To introduce the desired phase angle, the hand wheel 50 is turned until the counter 53 registers the correct angle. For e~ample, for one selected r~peat and for the No. 6 Deck, this angle is 113.2 degrePs. The hand wheel 50 is then turned until this numeral is registered on the counter 53. Thereupon, the loosely mounted collar 68 .~see FIGS. 3 and 6) is rota~ed until the detent 69 (see FIG.
3) is engaged by ~he ball ended shaft 70 of the plunger 71.
Ther~after the lock bolt 72 is tightened to irm1y clamp khe collar ~8 to the outer sleeve 38 -- the sleeves 38 and 36 being nonrotatably coupled to each other by virtue of ..: . .
the axial spline 37. With this manipulation perfo~ned, the preselected tooth is now at ~he predetermined phase angle rela~i~e to detent 69. When the register assembly is remo~ed from the fixture 43 and i~stalled in the press as part of a plate ~ylinder, the positioning of the detent will insure that the preselected gear tooth is at the same phase angle relative to the bail 70 ' .

~lL2~

1 For that purpose, the register asser~ly 35 is remo~ed ~rom the stub shaft 32' of the fixture 43 and ensleeved on the plate cylinder journal 32 -- see FIGS.
3 and 4~ More particularly, the pin 54 of the collar 55 is aligned with the keyway 42 of the journal 32 which means ~hat ~he preselected too~h is now in a predetermined, fixed relationship ~o the plate 40 on ~he plate cylinder 25. ~ock bolt 76 of collar 74 fixes the register assembly 35 on shaft 32. The pla~e 40 is n~w installed o~ ~he pla~e lo cyli~der 25 in a px~etermi~ed relationship to the scribe line 41 so that now the plate and preselected tooth are in the necessaxy relationship.

To get the preselected tooth into the proper relation-ship with the bull gear 34, use is made of the detent 69 --see FIG. 3. A counterpart ball 70' is provided as part of the subframe 26 carrying the plate cylinder 25.

Still referring to FIG. 3, it is seen that a portion of the subframe 26 is depicted at the lower le~t portion there-of and which carries a bearing 113 for supporting the journal 2~ 32 of the plate cylinder. The subframe 26 also carries an arm 114 which is equipped with a counterpart ball-providing mechanism to that on the positioning fixture 43. The arm 114 has a plu~ger 71' carrying the ball-ended shaft 70' ~ for engagement wi~h the detent 69. The ball 70l is urged .~ .
upwardly by means of an aix cylinder 115 carried by ~he arm 114~ When the air cylinder 115 is energized, the ball 70' rides against the outer surface of the collar 68 and, as ~he plate cylinder 25 îs rotated, eventual~y comes i~to engagement with the detent 69. This insures ~hat the pre-30 . selected t~oth is oriented at the proper phase angle relati~e to the preselected valley in the bull gear 34.

~-z~

At this point, however, the outér sleeve 38 carrying the pla~e cylinder gear 33 is still free to move axially rela~ive to the plate cylinder by virtue of its splined ~onnection 37 with respect to the fixed inner sleeve 36. Theref~re, I provide means for l~miting this axial movement and thereby position the center ~ of preselected tooth T in alig~ment with the center of the mating valley of the bull gear. This can be seen in the right hand portion of FIG. 3 and includes a ball bearing 116 fixed to the end of the journal 32. This bearing 116 is "capturad"
: .
by means of a half collar 117 pivotally mounted on the arm 114.
More pa~.ticul~rly, the arm 114 pivotally carries a bracket 118 which is pivotally connected to the arm as at 119. A locking lever 120 is provided to fix the bracket in its upright position so as to capture the bearing 116. When the plate cylinder 25 has been placed within the sub-frame 26, bracket 118 is pivoted from a horizontal position into that illustrated in FIG. 3 so as to half surround the ~ D~-116.
If the bearing 116 is not exactly aligned wi~h the half ~ollar 117, it can be mo~ed axially one way or the other by virtue of the spline connection between the collar 38 and the collar 36. This operation insures that the center of the plate cylinder gear aligns axially with the center of the bull gear. Therea~ter, locking lever 120 is tightened so that this position of register assembly 35 is maintained. Ater this, the entire plate cylinder ~nd ~he pre-locked register assembl~ is rotated until detent 69 .-.. . is engaged by the ball ended shaft 70' which establishes the proper ;::::::.-.
rotary reference for subsequent gear mesh be~ween the plate cyli~der gearing and bull gearing and automatic color-to-color registration as ~he ~arious decks are brought into nip enga~ement.

As a necessary precondition for proper year mesh between the central impression cylinder gear and the plate cyli~der gear, it is understood that the ce~tral impression cylinder-gear must be very accurately angularly positioned.

~z~ 34~

Since the gears are helical, it is therefore necessary to have a means that will always place the plate cylinder gear on the axial ::enter of the central impression c~linder gear so that the ce~ter of ~he gear will always be used as a point of reference in de~e~mining that proper angular rotation exists and proper gear mesh can occur.

_ I provide a centeri~g means f or the plate cylinder --- in the form of a positioning device generally designated as 123. The de~i~ë ~23 includes a cam roller 124 mounted on bracket 118. A ramp 125 is provided on the half collar 117 and when cam rollar 124 engages the ramp 125, valve 126 is shut ~f f thus indicating that the pistsn in hydraulic cylinder 121 is in mid-pc~sition and ~ at mid-position of cylinder ~21, collar 117 is in a predetermined position relative to the center of bull gears 34, 34 1 .

When the plate cylinder ~5 with register assembly 35 is installed in the machinet bearing 116 resting in groove 116 of collar 117 will position the center line of the plate cylinder gears 33, 331 in coincidence with the center line of the bull gears.

If the bearing 11 6 is not aligned with groove 116 ', axial movement of coattached collar 68 and sleeve 38 will mo~e bearing 116 into groove 116' and will place gears 33~ 33' .. in proper axial alignment wi~ the central ~mpresssion cylinder gears 34, 34 l .

Since the hydraulic cylinder is in mid stroke, it will ~e xecognized that when the machine is running, actuation of .hydraulic cylinder 121 wlll move helical gears 33, 33 ' axially xight or le~t and hence cause a slight angulax advance or retard of the bull gear 34 l 34 ' . This is commoIl practice and well known art.

The bull gear 34 is now rotated to a predetermined position by virtue of ~he sensor 98 of the proximity switch 97 sensLng the correct profile of a tooth so that when the plate cylinder 25 is mo~ed toward the central impression cylindes 22, the teeth of the gears associated with these .~eue~
two cylinders will mesh properly, ~ffe~E, before that mo~ement takes place, the a~ilox roll 28 is oriented to f.-...-..
the proper anyle in the manner previously described a~d using the ball and deten~ arrange~ment 109, 110 described in conjunction wi~h FIGS. 15 and 16.

Acc~rding to the invention, I pro~ide first and second alignment means on each OI the press 20 and the fixture 43 for properly orienting each plate cylinder 25. The first alignment means includes the keyways 42 and 42' engaged by the pin 54. Once these have been positioned properly,the lock means in the form of collar 55 locks ~hese elements in alignment~ The second alig~ment means includes the detent 69 and the "balls" 70 and 70'. Once the detent 69 has been positioned in alignment while in the fixture 43, the collar 68 is locked to preserve this alignment during transfer of the register assembly 35 to the sub~rame 26. Thereafter,the "ball7' 70' p~ovided as part cf the sub-frame 26 brings about the same orientation of the plate cylinder gear 33 as it was in the ~ixture 43.
, . ..
......
A third alignment means i~ provided for each transfer or anilox roll in the form of the detent 110 and ~he "ball" 109 - the detent 109 lo~ked into pre-determined relation with the plate cylinder helical gear 33 by means of the ~ollar 106 (see FI~. 16).

All of the necessary preconditions for automatic gear mesh and registration between decks exist and linear movement of subframe 27 for proper transfer cylinder to plate cylinder gear engagement as well as linear movement of subframe 26 for proper gear engagement between the plate cylinder gearing and central impression cylinder gearing can now occur to complete the change-over. This occurs by handwheel or motorized rotation of shaft 92, 92' (FIG. 2) and translated rotary motion on shafts 89 and 86 for subframes 26 and 27, respectively.

Since one revolution of the shafts 92, 92' produces a fixed and determinate amount of linear movement of the subframes, the use of hydraulic motors with ~eedback signals to known micro-processors becomes a system for "automatic" impression, that is, based on known values for different repeats, the microprocessor wiIl signal the hydraulic motor to move the subframes into impression positions and can determine accurately when the move-ment should stop.

After linear motion of the subframes is completed, subframe 27 is firmly locked against subframe 26 by cylinder 81, hence both frames are thus locked relative to the impression cylinder. Details of these lockup systems are shown in previously issued UO S. Patent No. 3,041,967.

For further explaining the best mode of practicing the invention certain trigonometric calculations are set down.
In the instant calculations, a horizontal deck position was selected for simplicity (No. 2 or No. 5 deck) as can be seen in FIG. 18. Decks l 3 - 4 - 6 involve additional mathematical formulae because the deck positions do not pass through the horizontal center line of the central ~-zq~

impression cylinder, but such additional formulae essentiall~
relate the other deck positions to the horizontal deck posi~i~ns and are additive for only those other positisns~
The calculations below essentially determine the position of the scribe line and the position of a specific gear tooth whe~ aligning the plate cylinder to the impression cylinder, and also detexmine the position of a gear tooth ~.-..:.. .
on the anilox roll such that it will properly mate with a corresponding ~all~ y in the plate cylinder gear when the decks are brought i~to pxinting impression~ In FIG. 18, certain s~mbols are shown as representing àrc lengths, and it is under~tood that arcuate lengths are always taken at ~he periphery of the roll or cylinder. In any event, knowi~g the diameter of a given cylinder, arc~ate lengths and angular measurements are determinate each from the other.
Essentially, the angle beta (~) i5 expressed as an angular measurement, but it can be converted to arcuate length and would be equal to A2. In essence, when point 90 on the plate cylinder is rotated through an angle beta, it will coincide with point 91 when both of these points reach and are coincident with the horizontal center line between ~he plate and impression cylinders.

These ~alculations show that c~rtain angles on downstream derks can be pre-determined ahead of time such ~, that automatic registration occurs as a specific point (91) is rotated around the central impression cylinder to reach various deck positions.

These calculatlons also show that ~y comparing angular rotation or arcuate lengths against ~h~ number of gear 30 teeth in~olved, the anilox roll can also be rotated to a pre determined position such ~hat gear mesh between the anilox and plate cylinder is accomplished when the decks are activa~ed.

~Z~8491 24.504" Re eat Pl_te Cylinder:

~ = 180 A~ (2~ R~j = 360 ~2~ x 30) = 94.248"

A2 = 94.248 ~ (3 x 24.504~ - 20.736"
24.S0-4 x 360 = 304 S42 ~....
Ani ox_Roll = 304,~.~42~ - 180 ~ 12~.642 46642 x 78 = 27.006 Teeth (Plate Cyl. Gear) Na 2370 x 58 - 43~500 Teeth (Anilox Roll ~ear) 0.500 - 0.006 = 0.494 Teeth (Out of Phase) 0'594 x 360 = 3.066 While in the foregoing sp~cification a de~ailed description of an embodiment of the invention has been set down for the purpose of illustration, may variations in the details hereingiven may ~e made by ~hose skilled in the art without departing from the spirit and scope of the i~vention.
, .
~ ' ..... .

Claims (15)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. In a method of achieving rotary registration in a press having a helical gear-equipped central impression cylinder and at least two helical gear-equipped plate cylinders, the steps of:
a) providing a positioning fixture separate from the press;
b) sequentially mounting each plate cylinder gear on the positioning fixture;
c) orienting each plate cylinder sear relative to a first reference on the positioning fixture which corresponds to a reference on the associated plate cylinder while the plate cylinder gear is mounted on the positioning fixture;
d) orienting at least one of the plate cylinder gears and said first reference on the positioning fixture relative to a second reference on the positioning fixture which corresponds to a reference on the press to provide a desired phase angle between said one plate cylinder and the other plate cylinder; and e) mounting the gear-equipped plate cylinders on the press and moving the plate cylinder gears radially into engagement with the impression cylinder gear.

2. In a method of achieving rotary registration in a press having a helical gear-equipped central impression cylinder and a helical gear-equipped plate cylinder, the steps of mounting said plate cylinder gear on a positioning fixture, orienting said plate cylinder gear relative to a first reference on the positioning fixture which corresponds to a reference on said plate cylinder while the plate cylinder gear is on the positioning fixture, orienting said plate cylinder gear and the first reference on the positioning fixture relative to a second reference on the positioning fixture which corresponds to a reference on the press, installing said plate cylinder gear on said press, and after installing said plate cylinder gear in said press, moving the said plate cylinder gear radially into engagement with the central impression cylinder gear.

3. A method of achieving register in a printing press having a central impression cylinder equipped with a gear, and a plurality of plate cylinder assemblies disposed circumferentially about the impression cylinder each of the plate cylinder assemblies including a plate cylinder having a shaft, and a reference point, and a register assembly mounted on the shaft, each of the register assemblies including a plate cylinder year and first alignment means for positioning a gear tooth of the plate cylinder gear with respect to the reference point on the plate cylinder, the printing press having second alignment means for each of said plate cylinder assemblies for positioning a tooth of each plate cylinder gear with respect to the impression cylinder gear, comprising the steps of:
a) providing a positioning fixture separate from the printing press, the positioning fixture having a shaft corres-ponding to the shaft of each of said plate cylinders, a reference point corresponding to the reference point on each of said plate cylinders, and third alignment means corresponding to each of the second alignment means on the printing press, b) sequentially mounting each register assembly of said plate cylinder assemblies on the shaft of the positioning fixture, c) orienting the first alignment means of each register assembly while it is mounted on the shaft of the positioning fixture to position the first alignment means with respect to the reference point on the positioning fixture, d) orienting the plate cylinder gear of each register assembly while it is mounted on the shaft of the positioning fixture to position a preselected tooth of the plate cylinder gear into alignment with the reference point on the positioning fixture, e) orienting the reference point on the positioning fixture relative to the third alignment means on the positioning fixture while each register assembly is mounted on the fixture to provide a different angular relationship between the reference point on the positioning fixture and the third alignment means for each register assembly, f) removing each register assembly from the positioning fixture and mounting the register assembly onto one of said plate cylinders to form a plate cylinder assembly, g) mounting said plate cylinder assemblies on the printing press, h) rotating each of the plate cylinder assemblies with respect to the second alignment means on the printing press for that plate cylinder assembly until the reference point of that plate cylinder assembly has the same angular relationship with the second alignment means on the press as it had with the third alignment means on the positioning fixture, and i) moving the plate cylinder assemblies toward the impression cylinder so that the plate cylinder gears mesh with the impression cylinder gear.

4 The method of claim 3 including the step of orienting the impression cylinder gear before the plate cylinder gears mesh with the impression cylinder gear so that a valley between mesh teeth of the impression cylinder gear is centered with respect to said preselected tooth of one of the plate cylinder gears.

5. The method of claim 3 in which said reference point on each plate cylinder is provided by a stop on the shaft of the plate cylinder, the first alignment means of each of the register assemblies including positioning means engageable with a stop on the shaft of a plate cylinder, the reference point of the positioning fixture being provided by a stop on the shaft of the positioning fixture corresponding to the stops on the shafts of the plate cylinders, including the steps of engaging the positioning means of each register assembly with the stop on the shaft of the positioning fixture when the register assembly is mounted on the positioning fixture, and engaging the positioning means of each register assembly with the stop on the shaft of the associated plate cylinder when the register assembly is mounted on the associated plate cylinder.

6. The method of claim 3 in which said printing press includes a coacting transfer cylinder assembly for each of said plate cylinder assemblies, each of the transfer cylinder assemblies including a transfer cylinder and a transfer cylinder gear, including the step of orienting each transfer cylinder gear rela-tive to the associated plate cylinder gear, and moving the transfer cylinders toward the plate cylinders when the plate cylinder assemblies axe moved toward the impression cylinder so that the transfer cylinder gears mesh with the plate cylinder gears substantially simultaneously with the meshing of the plate cylinder gears with the impression cylinder gear.

7. The method of claim 6 in which the printing press includes fourth alignment means for each transfer cylinder assembly, each transfer cylinder gear being equipped with detent means, including the step of orienting the detent means of each transfer cylinder gear into alignment with the fourth alignment means associated with the transfer cylinder gear to position a preselected gear tooth of the transfer cylinder gear relative to the associate plate cylinder gear.

8. The method of claim 3 in which each of said register assemblies includes a sleeve which can be mounted on the shaft of one of the plate cylinders, the plate cylinder gear of each register assembly being mounted on the sleeve of the register assembly, a collar surrounding the sleeve, the first alignment means of each register assembly comprising a pin extending through the collar and through a circumferentially elongated slot in the sleeve, the reference point of each plate cylinder being provided by a stop on the shaft of the plate cylinder, the reference point of the positioning fixture being provided by a stop on the shaft of the positioning mixture corresponding to the stops on the plate cylinder shafts, including the step of engaging the pin of each register assembly with the stop of the positioning fixture when the register assembly is mounted on the shaft of the positioning fixture, said step of orienting the plate cylinder gear of each register assembly comprising rotating the sleeve and the plate cylinder gear of the register assembly with respect to the pin and the stop of the positioning fixture and then locking the collar on the sleeve to prevent relative rotation between the sleeve and the pin.

9. The method of claim 8 in which each of the register assemblies includes a second collar rotatably mounted on the sleeve, the second collar having a detent engageable with the third alignment means of the positioning fixture, said step of orienting the third alignment means comprising the steps of rotating the shaft of the positioning fixture and the sleeve of the register assembly to a preselected angle, rotating the second collar with respect to the sleeve until the detent on the collar engages the third alignment means, and locking the second collar on the sleeve to prevent relative rotation between the second collar and the sleeve, said step of rotating each of the plate cylinder assemblies with respect to the second alignment means on the printing press for that plate cylinder assembly comprising rotating each plate cylinder assembly until the detent on the second collar of the plate cylinder assembly engages the second alignment means.

10. The method of claim 3 in which each of the register assemblies includes a collar rotatably mounted on the sleeve, the collar having a detent engageable with the third alignment means of the positioning fixture, said step of orienting the third alignment means comprising the steps of rotating the shaft of the positioning fixture and the sleeve of the register assembly to a preselected angle, rotating the collar with respect to the sleeve until the detent on the collar engages the third alignment means, and locking the collar on the sleeve to prevent relative rotation between the collar and the sleeve, said step of rotating each of the plate cylinder assemblies with respect to the second alignment means on the printing press for that plate cylinder assembly comprising rotating each plate cylinder assembly until the detent on the collar of the plate cylinder assembly engages the second alignment means.

11. A positioning fixture for a register assembly which is adapted to be mounted on the journal of a plate cylinder of a flexographic press, the register assembly including a gear and a detent, the positioning fixture comprising:
a) a base, b) a pedestal on the base, c) a shaft rotatably mounted on the pedestal and adapted to support the register assembly, d) lock means on the shaft for preventing relative rotation between the shaft and the register assembly, e) gear stop means movably mounted on the base and engageable with the gear of the register assembly for positioning a preselected tooth of the gear relative to the lock means, and f) alignment means on the base engageable with the detent of the register assembly after rotation of the shaft and the register assembly for providing an angular relationship between the detent and said preselected tooth.

12. The structure of claim 11 in which said fixture includes counter means for determining the angular orientation between the lock means on the shaft and the alignment means.

13. The structure of claim 11 in which said gear stop means includes a gauging block engageable with the gear of the register assembly for accurately positioning said preselected tooth with respect to said lock means on said shaft.

14. The structure of claim 11 in which said lock means comprises a keyway on the shaft.

15. A method of pre-aligning a register assembly for a printing plate cylinder in an off-machine fixture, the register assembly including a shaft, a plate cylinder gear surrounding the shaft, first locking means for locking the plate cylinder gear to the shaft, a collar mounted on the shaft, and second locking means for locking the collar on the shaft;
the fixture including a cylindrical stub shaft sized to receive the shaft of the register assembly, a first reference on the stub shaft, and a gear tooth gauge block; comprising the steps of:
(a) mounting the register assembly on the fixture by inserting the shaft of the register assembly into the stub shaft of the fixture;

(b) positioning the shaft of the register assembly relative to the first reference on the stub shaft;
(c) engaging the gear tooth gauge block with a gear (d) looking said first locking means so that said gear tooth of the plate cylinder gear is fixed on the shaft relative to the gear tooth gauge block and to said first reference;
(e) disengaging the gear tooth gauge block from said gear tooth;
(f) rotating the stub shaft of the fixture and of the shaft and the plate cylinder gear of the register assembly through a predetermined angle;
(g) rotating said collar on the shaft of the register assembly and positioning a reference on the collar with respect to a second reference on the fixture; and (h) locking said second locking means so that the collar is fixed on the shaft relative to the second reference, whereby said gear tooth of the plate cylinder gear is aligned with said first reference and is at a predetermined angle from said second reference. --