US2982204A

US2982204A - Printing unit for web presses

Info

Publication number: US2982204A
Application number: US572342A
Authority: US
Inventors: William A Roehm
Original assignee: Individual
Current assignee: Individual
Priority date: 1956-03-19
Filing date: 1956-03-19
Publication date: 1961-05-02
Anticipated expiration: 1978-05-02

Description

May 2, 1961- w. A. ROEHM PRINTING UNIT FOR WEB PRESSES 7 Sheets-Sheet 1 Filed March 19, 1956 M R Y BM M maKm Mun A H W I w. A. ROEHM PRINTING UNIT FOR WEB PRESSES May 2, 1961 7 Sheets-Sheet 2 m MP 7.31; a I VII/Illm I W A N% -0 U a n O w P I fl n .w v V u II ilk Q m 2 I. WWII... N I MW l I \NI w @WQ I g Q om Nfi Q Q Filed March 19, 1956 INVENTOR W 2% .Y O E PM Aim i May 2, 1961 w. A. ROEHM 2,982,204

PRINTING UNIT FOR WEB PRESSES Filed Mar ch 19, 1956 7 Sheets-Sheet 4 INVENTOR H ILUHM ,4 Poe/ M ATTORNEY May 2, 1961 w. A. ROEHM PRINTING UNIT FOR WEB PRESSES 7 Sheets-Sheet 5 Filed March 19, 1956 BY RoEHM M X w/ZL ATTORNEY w. AYVROEHM PRINTING UNIT FOR WEB PRESSES May 2, 1961 7 Sheets-Shept 6 Filed March 19, 1956 INVENTOR WILL/HM H. Poe/1M ATTQRN EY y 2, 1961 w. A. ROEHM 2,982,204

PRINTING UNIT FOR WEB PRESSES Filed March 19, 1956 7 Sheets-Sheet 7 INVENTOR ATTORNEY United States atent PRINTING UNIT non WEB rnnssns William A. Roehm, 881 N. Village Ava, Rockville Centre, NY.

Filed Mar. 19, 1956, Set. No. 572,342

7 Claims. (Cl. 101-447) This invention is a printing unit for use in a press of the type adapted to print upon a traveling web.

Printing units of this kind generally embody a printing roll to which ink is applied from a fountain by an interposed inking roll. The web to be printed travels over an impression or back-up roll as it passes through the zone of contact with the printing roll. Appropriate directional rolls guide the web to and from the impression roll and, in a multi-color press, direct the web to the impression roll of the next printing unit.

In conventional units of the character described, the printing, inking and impression rolls are commonly provided with trunnions, supported in bearings mounted in slides by which the rolls may be adjusted toward and away from one another and their bearings are generally of the type having caps which must be removed when it is desired to remove and replace one or more of the rolls. The adjustments referred to must be individually manually accomplished in a most painstaking manner and the removal and replacement of the bearing cap is slow and arduous.

The primary object of this invention is to provide a novel form of roll mounting which will materially simplify and expedite the removal and replacement of one or more of the rolls of any particular unit without the removal of bearing caps or other roll trunnion mountings and which will expedite the making of any necessary adjustments in a simple and convenient manner.

An important feature of this invention comprises a novel form of roll mounting wherein the inking and printing rolls are provided at their opposite ends with combined radial and thrust bearing elements coacting with complementary bearing elements carried by normally stationary axially alined stub shafts which are locked against rotation. At least one of the stub shafts of each roll is mounted for axial movement to permit it to be withdrawn from the roll to release the roll for removal from the press. 7

Another important feature consists in novel mechanism wherein the shafts which support the printing and inking rolls are respectively supported on arms fulcrum d, on a common axis and having associated means whereby they may be pivotally oscillated to separate the several rolls from one another and regulate said rolls into proper adjustment with respect to one another. This mechanism is constituted, as hereinafter described, to permit the rolls to be separated and thereafter returned to initial relation without impairing the initial adjustment. Furthermore this mechanism provides for simple and expeditious readjustment of the parts when printing rolls of different diameters are substituted for those previously in the press.

A further feature of the invention consists in a novel form of means for driving the several rolls in the proper directions and for synchronizing their respective peripheral speeds so that they efficiently cooperate with one another and with the traveling web.

The present invention also provides for peripheral speed and axial adjustment of the rolls to insure accurate 2,982,204 Patented May 2, 1961 Features of the invention, other than those adverted to, will be apparent from the hereinafter detailed description and appended claims, when read in conjunction with the accompanying drawings.

The accompanying drawings illustrate one practical embodiment of the invention, but the construction therein shown is to be understood as illustrative, only, and not as defining the limits of the invention.

Fig. 1 is a section taken longitudinally of the unit in substantially the plane of the line 11 of Fig. 2.

Fig. 2 is a section transversely of the unit taken in the plane of the line 2-2 of Fig. 1.

Fig. 3 is a section on the line 33 of Fig. 2.

Fig. 4 is a side elevation of the lower portion of the unit showing the mechanism for regulating certain levers which controlthe cooperative relation between the printing roll, inking roll and impression roll of the unit, cer-' tain parts being shown in section.

Fig. 5 is a section on the line 55 of Fig. 4.

Fig. 6, is a view of the machine illustrating the upper ends of the levers for supporting the inking roll and the printing roll and showing the manner in which the adjustment of these rolls may be held in proper spaced relation to one another and with the impression roll.

Fig. 7 is a graphic showing of the levers for supporting the inking and print-ing rolls and the means for adjusting them.

Fig. 7A shows a modified form of construction for moving the printing roll to and from the impression roll and for separating the inking roll from the printing roll.

Fig. 8 is a diagrammatic view showing the unit in plan and change speed mechanism for driving different rolls of the uni-t so that the rolls operate in directions to properly coact with one another.

Figs. 9 and 10 are schematic views showing the drives for the rolls whereby they are respectively rotated in the proper direction. Of these views, Fig. 9 shows the drive for the inking and impression rolls, while Fig. l0 shows the drive for. the printing roll.

Fig. 11 is a front view of a differential speed indicator to assist in adjustingthe speed of the rolls to uniformity.

Fig. 12 is a section on the line 1212 of Fig. 11.

The unit of the present invention comprises a frame 1 adapted to be mounted on a suitable bed which may be individual for the unit or may be of such length as to support a plurality of these units in tandem so that the web to be printed upon may be passed through said units in succession, as in a multiple color press.

Extending transversely of the frame 1 is a cylindrical fulcrum bar 2 (Figs. 1 and 2). This bar is secured against. rotation by a tie arm 3, one end of which is clamped to the bar 2, as shown in Fig. 1, while the other end is anchored to a rod 4 journaled in the frame 1. The bar 2 is mounted for axial sliding movement through bearings 5 in the opposite sides of the frame (Fig. 1) and this axial adjustment may be accomplished by an adjusting screw 6 having fixed collars on opposite sides of a bracket 7 rigid with the frame. A hand wheel 8 is aflixed to the screw 6, so as to effect the longitudinal movement of the fulcrum bar for axially adjusting the inking and printing rolls as hereinafter explained.

Each end of the fulcrum bar supports and forms a fulcrum for two levers. The levers nearest the opposite sides of the frame are designated 9 and serve to support the printing roll 10, while the more distant levers are designated 11 and serve to support the inking roll 12 and the ink fountain 13 with which the latter roll cooperates. The hubs of the levers are arranged to interfit, as shown in Fig. 2, and these levers -adjustment in any direction.

' roll. provided with rack teeth'23 which mesh with a pinion 24 (shown best in Figs. 2 and 6).

'ment, substitution or any other purpose. another roll of the same general kind may be mounted 3 are locked to the bar against relative axial movement by split rings 14 fitted into grooves in the fulcrum bar. The relation between the rolls and these levers is shown graphically in Fig. 7.

The impression roll 15 is mounted in a fixed bearing 16 on the frame 1 and is not normally intended for The printing roll and inking roll 12 are supported on the upper ends of the respective levers by a novel form of mounting shown best in Figs. 2 and 6. The printing roll may be of any appropriate kind to produce a well known kiss-printing, although any other type of roll may be employed. Contrary to the usual practice, this roll is not provided with a shaft rigid therewith and extending from its opposite ends, but has a novel form of mounting which facilitates its quick removal without the necessity of removing bearing caps and other adjuncts heretofore common in printing roll mountings. Q

As shown best in Fig. 2, the roll 10 is provided in each of its ends with a plug 17 rigid with-the body of the roll and of substantially cup shaped form. Within the cup is a bearing element 18 adapted to cooperate with roller bearings 19 which, in turn, coact with a bearing race 20 rigidly mounted on the reduced end 21 of a stub shaft 22. This arrangement is common to both. ends of the printing roll 10. One of the stub shafts 22 at the right hand end of the roll, as shown in Fig. 2, is

-mounted rigidly in the upper end of the upper arm of the right hand lever 9. The stub shaft 22 which coacts with the other end of the roll is mounted for sliding movement through the upper end of the upper arm of the companion lever 9 at the corresponding end of the This stub shaft is locked against rotation, but is This pinion is supported in the upper end of the lever 9 and may be rotated by an appropriate wrench applied to the square or hex hub 25 of said pinion. Through rotation of this pinion, the left hand stub shaft 22 of Fig. 2 may be inoved end of the printing roll 10 and said roll may then be shifted axially to the left to withdraw it from the corresponding bearing at its opposite end and thus free the roll, so that it may be lifted out of the unit for replace- The same or in the unit by'simply reversing the operation stated.

It will be noted that the upper end of each lever 9 is slotted and bolts 26 are provided to constrict the slots and normally lock the stub shafts 22 in adjustment. The inking roll 12 is mounted in identically the same way as the printing roll 10 and may be removed from or introduced into the unit in a like manner, but it should be noted that the inking roll 12, as well as the fountain 13, is supported upon the upper arms of the levers 11,

-i.e., above the fulcrum bar.

With this arrangement, it will be apparent that the oscillation of the

levers

9 and 11 may be utilized to move the rolls into and out of cooperative relation with one another to either bring them into proper cooperative relation or to separate them to permit of the removal of either the printing roll or the inking roll, as may be desired.

As shown in Fig. 6, a stop screw 27 is associated with each of the bearings 16 and a similar stop screw 28 is associated with the upper end of the ,arm of the lever 11. These stop screws are provided so that, after the parts have been properly adjusted and one or more of the rolls is removed, they may be returnedto their exact scraper 30, preferably of the general type and character claimed in Patent No. 2,704,026 March 15, 1955. As shown in Fig. 1, the bracket 29 is pivoted at 31 and the blade 30 is supported on a pivoted blade carrier 32 normally held in position to engage the blade with the periphery of the inking roll by a spring 33, the outer end of which is fastened to an arm 34 of a bell crank, fulcrumed at 35. The arm 34 and the spring 33 constitute, in effect, a toggle which can be broken by operating the handle 36 to withdraw the blade 30 from the roll when desired.

As shown in Fig. l, the toggle is in position slightly over dead center to hold the blade in contact with the roll while the spring 33 permits the blade to retract in the event that it encounters an unyielding obstruction on the roll.

The several rolls of the unit are driven in the following manner: Power is supplied from a prime mover, such as an electric motor not shown, to a main drive shaft 37, Fig. 8, connected to and operating a variable speed drive mechanism 38 of any well known and conventional type which has two power take-off

shafts

39 and 40, the relative speed of which may be varied as the variable speed mechanism is regulated. These two power takeoff shafts respectively drive two

shafts

41 and 42, Figs. 2

and 3, in opposite directions. The shaft 41 carries a helical worm gear 43 while the shaft 42 carries a like gear 44. Worm gear 43 meshes with a gear 45, while worm gear 44 meshes with a gear 46. These two

gears

45 and 46 are coaxial with the fulcrum bar 2 and are each rigid with a pair of duplex gears mounted for rotation on the bearings 5. Duplex gears of the gear 45 are designated 47, while those of the gear 46 are designated 48. Ball or roller bearings are interposed between the gears 47 and 48 and their respective bearings 5 and these duplex gears operate in opposite directions.

The purpose of this is to drive the printing roll in one direction and the inking roll and impression roll in a counter direction, so that the rolls may properly cooperate with one another while in contact directly with one another or on an interposed web which is designed W in Fig. 1.

As shown best in Fig. 2, the duplex gears 48 mesh with corresponding gears 49 mounted to freely rotate about stub shaft 22 and said gears 49 carry one or more pins 50 which extend to the left and enter into a corresponding number of openings 51 in the plug 17 at the right hand end of the printing roll and serve to rotate said roll. The pins 50 and the openings 51 function as a detachable clutch connection. Fig. 10 diagrammatically shows this gearing, it being manifest from this figure that the printing roll is rotated in an anti-clockwise direction and there are no connections in this particular train of gears with the inking roll 12 or impression roll 15.

The inking and impression rolls are in like manner driven from the duplex gears 47 through a train of gearing shown in Fig. 9 wherein the duplex gears 47 are shown as meshing with like gears 52 having a pin connection with the corresponding end plug of the inking roll. The gear 47 also meshes with a gear 53 fixed on a shaft 54 of the impression roll 15. From Fig. 9 it appears that the inking and impression rolls are rotated in the same direction and that there is no gearing connection through this train with the printing roll 10.

In the accompanying drawings duplex gears are shown although in practice I may use a single gear in place of each pair of duplex gears.

With the gearing described and particularly by virtue of the pin drive connection to which I have referred, it is possible to axially adjust both the printing roll and inking roll without correspondingly adjusting the gear trains which drive them for the pins 50 through which the rolls are driven are sufiiciently long to permit of such axial registration which is particularly important where a number of units of the present invention are positioned end to end in a multi-color press. It will be recalled that this lateral adjustment is accomplished by operation of the hand wheel 8 (Fig. 2) which serves to axially shift the fulcrum bar 2 and the

levers

9 and 11 which are supported thereby and which in turn support said rolls. The sliding connection between this bar and the bearings 5 permit the gears 45-48 to remain fixed in an axial direction for the bearings 5 are locked against axial movement by fixed collars 55 (Fig. 2).

Registration in a direction longitudinally of the web is obtained by advancing or retracting the relationship between the worm 44 and the gear 46 which drives the printing roll. This adjustment is accomplished by the mechanism shown in Fig. 3. In this figure there is shown mounted on the frame a hand wheel 56 rigid with a gear 57 which meshes with a pinion 58 fixed on a shaft 59. This shaft is mounted for rotation in a gear box on supported on the frame 1 of the machine and a portion of said shaft is threaded as at 61 and extends through a threaded lug 62 formed on a'hanger 63 which is suspended from the hub of the worm 44. The hub of this worm is keyed to the shaft 42, so as to be rigid therewith. By rotating the hand wheel 56, the worm is axially shifted to advance or retard the relative arcuate relation between the gear 48 and the web as may be required to obtain proper registration between plate rolls of adjacent units.

It will be noted from Fig. 3 that the shaft 42 has slip connection couplings 64 at its opposite ends with

alined shafts

42a and 42b which extend to shafts 42 of adjacent units of the press, so that the shafts 42 of all of said unitsmay be driven from the main drive shaft 37 of Fig. 8, although the elements of each one of these units may be independently adjusted for axial and circumferential registration.

I have hereinbefore explained that the

levers

9 and 11 are mounted for pivotal oscillation about the common axis of the fulcrum bar 2 in order to move the rolls toward and away from one another and in order toobtain the proper relation between said rolls. The preferred form of mechanism whereby this is accomplished is shown in Figs. 4 and 5 and while other mechanism appropriate to its operations may be employed that here illustrated has. been found to be highly efficient and convenient in practice. 7

As shown in these figures, the levers 11 are adjusted with respect to the levers 9, while the latter levers are adjusted with respect to the frame. For adjustment of the lever 9 with respect to the frame, the rod 4 is mounted to oscillate and there is rigid with said rod an arm 65 having a handle 66 whereby said arm may be oscillated. Also rigid with said arm is a link 67 and the outboard end of said link carries a pivot 68 which attaches to the link the head of a screw 69. This screw 69' has threaded connection with a tubular nut 70 to which is aflixed a helical gear 71 normally meshing with a helical pinion 72 fixed on a shaft 73 to one end of which is attached a hand wheel 74. When the hand wheel is rotated, the helical gear 71 is turned to adjust the nut 70 longitudinally of the screw 69. The nut 71} has a bearing in a housing 75'. supported on shaft 73 and it also has a bearing in the head 76a of a trunnion 76 which extends through a bearing in one of the levers 9 near the lower end of the latter. Rotation of the hand wheel 74 will move the lower end of the lever 9 one way or the other and thus-permit a very nice adjustment of the upper end of the latter and the corresponding-end of the plate roll carried thereby.

The mechanism described with respect to the arm 9 shown in Fig. 4 is duplicated for the arm 9 at the other side of the machine except that only one arm 65 and handle 66 are required. Each screw 69 and link 67 constitute a toggle which in Fig. 4 is shown slightly over t) dead center wherein a stop is provided to normally maintain them in this position. If it be assumed therefore that, with the parts in the position shown, the printing roll is in proper adjustment and in correct relation with respect to the impression roll, the printing roll 10 may be instantly moved away from the impression roll 15 by simply grasping the handle 66 and moving the arm 65 clockwise to break the toggle and thus move the lower end of the lever 9 to the right in Fig. 4 with corresponding movement in the opposite direction in the upper end of the lever and the printing roll. By reversing the operation stated, the parts may be returned accurately to the initial adjustment. These operations conjointly move both the printing and inking rolls.

The adjustment for the levers '11, illustrated in Fig. 4, is identical with the adjustment for the levers 9 with one exception, namely, that the lever 9 is adjustable with respect to a shaft or rod 4 which is mounted for oscillation in the frame 1, whereas the levers 11 are adjustable with respect to a shaft 77 which extends transversely through the machine and is mounted for oscillation near the lower ends of the two levers 9. Fixed to this shaft 77 is an arm 78 having a handle 79 by means of which the shaft 77 is oscillated. The toggle is composed of two

links

80 and 82 pivoted on an elbow pivot 81 and the adjustment is made through a helical gear 83 meshing with a pinion 84 supported in the housing 86. The tubular nut carries a trunnion 87 which extends into the lower end of one of the levers 11. The parts for adjusting the levers 1 1 are duplicated at opposite sides of the machine except that only one arm 78 and handle 79 is required. For adjustment of the inking roll with respect to the printing roll, a hand wheel 74a is provided and for a quick withdrawal of the inking roll from the printing roll without destroying its adjustment, the arm 78 is operated through the handle 79 as will be apparent from the foregoing description.

It is of course necessary that the axes of the inking, printing and impression rolls be parallel to one another and to permit of independent adjustment of one end of each of the printing and inking rolls, the shafts 73 and S5 at one side of the machine are mounted inslotsin the housings and 86, respectively, and are spring pressed so as to normally engage the pinion 72 with the gear 71 and the pinion 84 in engagement with the gear 83. Should the said parallelism be lacking when a new roll is put in, the pinlons 72 and 84 may be withdrawn from their gears against the tension of the springs 88. When these pinions are retracted, their coacting gears may be turned a tooth or two as the case may require to produce the parallelism referred to.

The mechanism shown in Figs. 4 andS is highly efficient and provides for accurate adjustment of the rolls with respect to one another and for quick and easy separation of the rolls when desired with quick and easy return of the rolls to initial adjustment.

Another form of mechanism for adjusting the rolls with respect to one another and which may be used in lieu of the toggles shown in Figs. 4 and S is shown in Fig. 7a. In this figure, a fluid pressure cylinder 67a is substituted for the toggle link 67 and has therein a piston the stem 69a of which is substituted for the link 69. In like manner a fluid pressure cylinder a is substituted for the link 80 and is provided therein with a piston, the stem 82a of which corresponds to the link 82. By controlling the feed of compressed air or liquid under pressure to the respective cylinders or by venting the cylinders, as the case may be, the relative positions of the several rolls may be controlled and regulated as desired.

It is of course essential to the proper functioning of an intaglio printing machine that the printing roll and impression roll operate at the same peripheral speed and I have shown in Figs. 11 and 12 a differential speed indicating mechanism which may be utilized to assist the adjustment of the machine to produce such identical pesuitable bearings, a main shaft 91 and two counter shafts 92 and '93. Mounted to freely rotate on the main shaft 91 are two

bevel gears

94 and 95. To thehub of the bevel gear 94 is secured a gear 96 and to the hub of the bevel gear 95 is aflixed a gear 97. The

gears

94 and 95 are spaced apart and mesh with a plurality of

satellite bevel gears

98 and 99 which are freely rotatable on stub shafts 100. The inner ends of the stub shafts 100 are pinned to a fitting 161 which embraces the main shaft 91 and is pinned thereto, so that the satellite gears 98 and 99 will bodily rotate about the axis of the main shaft 91, while the satellites individually, as well as the

gears

94 and 95, are freely rotatable on their respective shafts.

One of the gears 96 meshes with a pinion 102 fixed on one of the counter shafts 92, while the gear 98 meshes with a pinion 103 fixed on the other counter shaft 93.

Fixed at one end of the counter shaft 92 is a friction wheel 104, While a similar friction wheel 105 is fixed on the corresponding end of the other counter shaft 93. Rigid with the corresponding end of the main shaft 91 is a pointer 106 which operates over a dial 107 on the exterior of the casing, as shown best in Fig. 11.

In utilizing the differential speed mechanisms shown in Figs. 11 and 12 the device is held, either by a suitand the

satellites

98 and 99 will simply rotate on the axes of the stub shafts 100, without imparting any rotation to the main shaft. However, if the rolls or 15 are rotating at different speeds, then the bevel gears 94 and 95 will be rotated at different speeds with the result that the satellites will be caused to bodily shift their position in opposite arcuate directions about the axis of the main shaft 91 and in so doing will shift the pointer over the dial from the proper zero position of Fig. 11 to the right or left as the case may be and will thus indicate a difference in speed, at the same time indicating which roll is operating faster. The operator may then regulate the printing machine, as hereinbefore described, to bring the speeds of the two rolls into harmony. With the apparatus shown in Figs. 11 and 12, there is no guess work involved. The adjustment may be obtained in a simple and expeditious manner to insure proper operation of the machine.

From the foregoing detailed description, it will be apparent that the present invention embodies many novel features. There are no rotating shafts on any of the rolls and no slides for adjustment. No gears need be changed for the adjustment of surface speeds of printing rolls of different sizes for appropriate regulation may be made in the variable speed mechanism at the power input. The inking and printing rolls will run true because the stub shafts on which they are mounted are rigidly supported and the rolls run freely on tapered thrust bearings. Most of the gears employed, except where specifically referred to to the contrary, are preferably of the herringbone or helical type and supported in anti-friction bearings. The several levers which support the rolls may be quickly and easily adjusted and, during the operation of the press, are rigidly locked in position so as to prevent vibration.

I wish to place particular emphasis on the ability to quickly break contact between the rolls without destroying the adjustment between them. This makes possible easy removal of any roll. For example, if after setting up the plates on the printing roll, it is found that one of them is out of register and needs extra makeready,

the contact between the rolls may be broken by operating the arms 65 and 7 8, the roll may be removed and th necessary corrections made, and thereafter the roll may be replaced in the machine and the

arms

65 and 78 returned to printing position and to bring all of the rolls back in their precise original positions of adjustment.

These features and others which will be apparent to those skilled in the art from the foregoing description very materially aid in preparing the unit for printing and are greatly appreciated by mechanics and press operators for they make the work easy, save time and insure high class printing and registration.

The machine which I have described embodies many novel features, some of which may be employed without necessarily employing all and I therefore wish it understood that the present invention is not limited to the details of construction shown in the drawings but is to be understood as fully commensurate with the appended claims.

Having thus fully described the invention, what I claim as new anddesire to secure by Letters Patent is:

1. A printing unit comprising: a frame, a horizontal fulcrum bar mounted on the frame, printing and inking rolls, levers fulcrumed on the fulcrum bar and carrying stub shafts locked against rotation and rotatably supporting the opposite ends of the printing roll, additional levers also fulcrumed on the fulcrum bar and carrying stub shafts locked against rotation to the latter levers and rotatably supporting the opposite ends of the inking roll, means for pivotally moving the levers to bring said rolls into and out of proper cooperative relation with one another, a gear on one of the stub shafts supporting the printing roll having a clutch connection with the printing roll to drive the latter, another gear on one of the stub shafts on the inking roll having a clutch connection with the inking roll to drive the latter, a gear on the fulcrum bar connected to the gear on the stub shaft of the printing roll to drive the latter, another gear on the fulcrum bar connected to the gear on the stub shaft of the inking roll to drive the latter, separate worm gears connected to the respective gears on the fulcrum bar, a variable speed mechanism connected to both Worms to drive them in appropriate directions at speeds to provide uniform peripheral speeds for the printing and inking rolls, and a prime mover for driving the variable speed mechanism.

2. A printing unit according to claim 1, comprising means for axially shifting the worm which drives one of the rolls for circumferential registration purposes.

3. A printing unit according to claim 2, comprising means for axially shifting the fulcrum bar to obtain lateral registration.

4. A printing unit comprising: a frame, a horizontal fulcrum bar supported on said frame for axial movement along a fixed axis, two pairs of levers all fulcrumed on the fulcrum bar with the levers of each pair at opposite sides of the unit, a stub shaft mounted against rotation on each of the levers of each pair with the stub shafts of each pair of levers extending toward and coaxial with one another, an anti-friction bearing carried by the contiguous ends of each pair of stub shafts, a printing roll supported at its opposite ends by the bearings of the stub shafts of one pair of levers, an inking roll supported by the bearings of the stub shafts of the other pair of levers, a gear coaxial with one of the stub shafts which supports the printing roll and provided with a detachable clutch connection between said gear and said roll, means for driving said gear while the stub shafts which support said printing roll remain stationary, said means for driving the gear on the stub shaft of the printing roll comprising a prime mover and a train of gears leading to and meshing with the gear on said stub shaft, and means for advancing and retarding the gear train between the prime mover and the gear on the stub shaft for registration purposes in a .direction circumferentially of the printing roll.

of said rolls individually, means for adjusting the levers of each pair about their common fulcrum axis at the fulcrum bar to regulate the contact pressures between the printing and impression rolls and between the'printing and inking rolls while the driving connections for all of said rolls remain intact, said means embodying a connection between the frame and one lever of one pair and a like connection between the latter lever and a lever of the other pair, each such connection embodying a toggle one link of which isthreaded into a nut pivotably supported on one lever, and means for rotating said nut to pivotally adjust that lever on the fulcrum bar. 2

6. A printing unit according to claim 5, wherein the means for rotating the nut comprises a gear locked against rotation to the nut, and' a manually operable pinion meshing therewith.

- 7 A printing unit comprising: a frame, a stationary impression roll on said frame, a fulcrum bar supported on the frame for axial adjustment along a fixed axis with means for so adjusting said bar, two pairs of levers all fulcrumed on the fulcrum bar with the levers of each pair at opposite sides of the unit, a printing roll supported by the levers of one pair, aninking roll supported by the 1,387,941 Petri Aug. 16, 1921 1,737,378 Littel Nov. 26, 1929 1,970,894 Maag Aug. 21, 1934 2,069,613 Koppe Feb. 2, 1937 2,138,142 Dietrich Nov. 29, 1938 2,146,963 Lang Feb. 14, 1939 2,242,945 Edwards May 20, 1941 2,258,653 Klingelfuss Oct. 14, 1941 2,341,202 Barber Feb. 8, 1944 2,380,004 Wilderson July 10, 1945 2,405,795 Luehrs Aug. 13, 1946 2,460,504 Huebner Feb. 1, 1949 2,573,090 Beasley r Oct. 30, 1951 2,639,666 Halley May 26, 1953 2,653,539 Halley Sept. 29, 1953 2,683,273 Hayner July'13, 1954 2,787,954 1 Gaudet et a1 Q. Apr. 9, 1957 of each pair about their common fulcrum axis at the fulcrum bar to regulate the contact pressures between the printing and impression rolls and between the printing and inking l'Olls while the driving connections for all of said rolls remain intact, said means including toggle connections between the levers which support the inking roll and the levers which support the printing roll for pivotally swinging the inking roll free from the printing roll,

and toggle connections between the frame and the levers which support the printing roll for conjointly pivotally swinging both printing and inking rolls toward and away from the impression roll.

References Cited in the file of this patent UNITED STATES PATENTS Crawford Oct. 15, 1957