US2986088A

US2986088A - Inking arrangement for rotary printing press

Info

Publication number: US2986088A
Application number: US689360A
Authority: US
Inventors: Chase Corson Walter; Doyle Frank Joseph
Original assignee: Miehle Goss Dexter Inc
Current assignee: Miehle Goss Dexter Inc
Priority date: 1957-10-10
Filing date: 1957-10-10
Publication date: 1961-05-30
Anticipated expiration: 1978-05-30
Also published as: DE1176674B

Description

May 30, 1961 c. w. CHASE ETAL 2,986,088

INKING ARRANGEMENT FOR ROTARY PRINTING PRESS Filed Oct. 10, 1957 2 Sheets-Sheet 1 MEANS FOR DRIVING m sYNc.

STEP DOWN DRIVING CON NECTION INVENTORS Coesou WALTER Cruse FRANK JOSEPH DOYLE- May 30, 1961 c. w. CHASE ETAL INKING ARRANGEMENT FOR ROTARY PRINTING PRESS Filed Oct. 10, 1957 2 Sheets-Sheet 2 INVENTORS Coesou WALTER CHASE FRANK JOSEPH Dovu:

COUPLING lolsi VAR. SPEED Y TO PRESS DRIVE Patented May 30, 1961 INKING ARRANGEMENT FOR ROTARY PRINTING PRESS Corson Walter Chase, Oak Park, and Frank Joseph Doyle, Bellwood, Ill., assignors to Miehle-Goss-Dexter, Incorporated, Wilmington, Del., a corporation of Delaware Filed Oct. 10, 1957, Ser. No. 689,360

11 Claims. (Cl. 101-350) The present invention relates to inking arrangements and more particularly to a means for coating printing plates with ink in a high speed rotary printing press.

In spite of the fact that much attention has been given to the problem of inking the plates in a rotary press over the years, conventional inking arrangements have a number of inherent drawbacks. From the standpoint of the result, such inking arrangements have failed to produce an even film on the printing plate over all of its area in successive revolutions of the plate cylinder, this defect being commonly evidenced in ghosting and starvation, the terms applied to non-uniform ink distribution circumferentially and longitudinally ofthe plate cylinder. Ghosting, for example, may occur where there is a cut, block or other heavily inked area on a printing plate which takes a larger amount of ink from the form roller than do corresponding areas in the same column and circumferentially spaced therefrom. In spite of the fact that the film is reformed on the form roller between successive rotations, such reforming is brought about primarily by uniform addition of ink to the form roller which is not adequate to restore a full film of ink in those areas which have, during the previous revolution, been called upon to supply ink heavily. The result is that such areas on the form roller are under-inked and tend to form a negative image or ghost of the heavily inked areas in an off-set position in the same column.

By way of example, it will be assumed that the printing plate in a given column position has several distinctively shaped areas which require solid inking, the in-between areas being more lightly inked and in the form of text or half-tones. It is frequently found that in the final result one or more of solidly inked areas will include the ghost of another one of such areas, i.e., one of the areas will not be solidly inked but will have superimposed thereupon a more lightly inked area of distinctive outline or shape. While a certain amount of ghosting can be tolerated, this is generally interpreted as a sign of poor printing, and elaborate arrangements have been worked out in an eifort to reduce this effect to a reasonable or unnoticeable level.

Starvation, or non-uniform distribution of ink longitudinally along the plate cylinder, results from the fact that different amounts of ink are frequently required from column to column due to the presence of heavily inked cuts in some of the columns. In order to minimize starvation, ink fountains are generally provided with a series of spaced keys which adjust the clearance of the fountain blade, thus causing more ink to be fed at some column positions than at others. The aim in adjusting the keys is to regulate the ink fed in each column position to that required by the corresponding column on the plate. One problem is that the ink requirements on the plate vary abruptly at the edges of heavy half-tones and solid areas, and it is not possible by adjustment of keys to define the upwardly fed ribbons of ink with such abruptness. Consequently, ink transfer rollers are sometimes vibrated axially in an eiiort to smooth out sharp variations in ink film from column to column so that variations in the film applied to the printing plate are gradual and therefore less noticeable to the eye in the final printed product.

As is well known to one skilled in the art, adjustment of the fountain keys is an operation which must be performed by highly skilled pressmen and at best is a process of trial and error. Consequently, there is considerable wastage of paper before finally arriving at an adjustment in which the starvation effects are reduced to a tolerable level. Moreover, each change in plates or set-up requires a complete readjustment of the fountain keys which must be performed as rapidly as possible in getting out each edition of a newspaper. This requires that a large staff of skilled pressmen be available to effect the change-over even though such pressmen are not required during the normal run of the press.

Accordingly, it is an object of the present invention to provide a novel inking arrangement which substantially eliminates both ghosting and starvation.

It is another object to provide a novel inking arrangement in which the returned ink film is substantially completely stripped from the form roller following the inking of the plate and the film reformed on the form roller to a uniform thickness in both the peripheral and axial directions prior to the next application of ink to the printing plate.

It is a further object of the invention to provide a novel inking arrangement which does not require fountain keys and in which the ink film is fed at a constant thickness, column by column, along the length of the ink feeding device or fountain under all conditions of operation. It is consequently an object of the present invention to permit the elimination of the column-by-column feed adjustment and therefore the necessity for any readjustment when changing from one set of plates to another. It is an important object to provide an inking arrangement which is capable of applying a uniform film of ink to all areas of a printing plate regardless of the density of the image to be printed and regardless of abrupt changes in density from area to area either peripherally or axially along the plate.

It is still another object of the present invention to provide a novel inking arrangement which may be employed for either direct or reverse rotation of the printing cylinder and in which change-over from one condition to the other may be accomplished in a minimum amount of time and with simple mechanical elements.

It is an additional object to provide an inking arrangement in which there is no necessity for evening out the ink in the axial direction along the ink feeding path, and consequently in which it is not essential to vibrate the ink rollers. It is, however, an object of the invention in one of its aspects to provide an arrangement of vibrated rollers, along both the feed and return paths, which is considerably simpler than conventional vibrating mechanisms and in which some or all of the ink rollers may be vibrated by a common driving element.

It is still another object of the invention to provide an inking arrangement employing a single form roller which includes and permits use of a replaceable outer covering in the form of a strip of material having two peripheral ends and which may be easily removed from the press for resurfacing or replacement. It is a related object to provide a form roller of the above type in which the gap has no effect upon the uniformity of the ink film applied to the printing plates.

It is a further object of the present invention to provide an inking arrangement which permits use of any desired type of ink fountain capable of supplying ink in thinly distributed form. More specifically, it is an object to provide an inking arrangement in which the ink may be applied directly to the form roller by the ink feeding device or fountain assembly and in which the film is completely formed and made uniform on the form roller without necessity for passing such film through an extended series of rollers and drums, which characterize the usual inking arrangement. Accordingly, it is an object of the present invention to provide an inking arrangement which is extremely simple, compact, and inexpensive as compared to prior devices while nevertheless possessing all of the features referred to above. Finally, it is an object to provide an inking arrangement which may be operated and maintained by relatively unskilled personnel.

Other objects and advantages of the invention will become apparent upon reference to the attached detailed description and upon reference to the drawings in which:

Figure l is an end view of a printing press unit employing the present invention with the end frame removed and with only one-half of the unit being shown, it being understood that the same construction is repeated in the remaining half;

Fig. 2 shows in detail a typical blade assembly of the type used in Fig. 1;

Fig. 3 is a fragmentary view showing the joint between the ends of the blanket on the form roller; Fig. 4 shows a linkage employed for silencing the blades on one side of the inking arrangement and activating the blades on the remaining side, depending upon whether the press is being rotated in the forward or reverse direction.

Fig. 5 is a transverse fragmentary view showing the arrangement provided for simultaneously vibrating all of the inking rollers;

Fig. 5a is a fragmentary view of an alternate wobble plate driving arrangement;

Fig. Sb is a detailed view of a roller pulley; and

Fig. 6 is an end view of the vibrating mechanism looking along the line 6-6 in Fig. 5.

While the invention has been described herein in connection with a preferred embodiment, it will be understood that we do not intend to limit ourselves to the embodiments shown but intend to cover all alternative and equivalent constructions falling within the spirit and scope of the appended claims.

Turning to Figure l, the press generally indicated at 10 will be recognized as the type having an inverted U-shaped frame usually employed in the printing of newspapers, only one-half of the press unit being shown, the remaining half being a mirror image of that disclosed. The press unit 10 has a plate cylinder 11 having plates 11a and 111), which may, for example, be in the form of stereotype plates. Cooperating with the plate cylinder is an impression cylinder 12 about which is trained a Web 13.

For applying a film of ink to the upraised areas of the printing plates, an inking arrangement 20 is employed which includes an ink fountain 21 having an ink trough 22, a fountain roller 23 and a feed roller 24. For controlling the amount of ink supplied to the system by the fountain roller a blade 25 is provided which extends longitudinally therealong. Such blade may have provision for bodily adjustment, as indicated at 26, relative to the fountain roller although as pointed out below there is no necessity in the present device for the multiplicity of adjusting keys usually provided for varying the amount of ink fed to the system column by column. The feed roller 24 may, for example, be of the type disclosed in McWhorter Patent 2,613,600 to which reference is made. It will suffice in understanding the present device to state that the feed roller 24 is in the form of a multi-sided polygon having flat areas thereon defining longitudinally extending ridges which successively wipe ink from the film which is formed on the fountain roller, the fountain roller preferably operating at a speed which is a small fraction of that of the feed roller. The effect is to apply ink to the form roller in thinly distributed form. Converting the 4 ink into a uniform film is taken care of by the arrangement to be described in the following paragraphs.

In accordance with the present invention, a single form roller 30 is provided between the ink feeding device and plate cylinder, such form roller having a plurality of inking rollers peripherally spaced about each of its sides and with at least a portion of the rollers on the return side being provided with means for stripping off the ink filrn therefrom. In the present embodiment, it will be assumed that the plate cylinder is driven clockwise and hence that the form roller is driven counterclockwise defining a feed side 30a at the right and a return side 30b at the left. Turning attention to the series of ink rollers at the left hand side, these are shown as five in number and are indicated at 3135 respectively. The ink rollers at the right hand or feed side are also, in the present embodiment, five in number and are indicated by the numerals 41-45. It will be understood that in the illustrated embodiment the rollers 31--35, 41--45, referred to are rotated by reason of their contact with the form roller 30 and hence may be referred to as rider rollers. In carrying out the present invention, the ink roller 33 on the return side is engaged by a blade assembly 51 and the successive roller 34 is engaged by a blade assembly 52.

Corresponding blade assemblies

53, 54 are provided for the rollers 43, 44 although, as will become clear, the

assemblies

53, 54 are silenced, i.e., retracted or inoperative, when the cylinders in the press unit are rotating in the directions shown.

With regard to the details of the blade assembly, the assembly 51, shown in Fig. 2, may be taken as representative. The assembly includes a body 60 which extends longitudinally across the press and is mounted for rocking about stub shafts 61 or the like at each end. Mounted on the body 60 is a clamping plate 62 secured by a series of cap screws 63 or the like, only one of which is shown. interposed between the body and clamping plate is a composite stripper which preferably consists of a blade 64 of tough plastic as, for example, nylon, tenitc, or the like, having a high degree of wear resistance and backed up by a spring steel blade 65. The clamping plate 62 is provided with a series of set screws 66, the lower ends of which abut the body 60 so that tightening the screws tends to rotate the clamping plate 62 through a small angle thereby to clamp the

blades

64, 65 securely together.

Under operating conditions, the blades included in the

blade assemblies

51, 52 press against the

ink rollers

33, 34 along the entire length of the latter, thereby to strip off the residual ink film which is picked up by the

rollers

33, 34 from the form roller 30 after the image or form on the plates has been inked. The ink which is stripped off drips into a pan 71, a corresponding pan 72 being used on the other side. Any ink which is not actually stripped from the ink rollers is left in the form of a thin even film. Provision may be made, as shown, for draining the pans 71, 72 into the trough 22 of the ink fountain.

Prior to describing the operation of the device, more detailed reference may be made to the construction of the form roller 30. The form roller is provided with a replaceable resilient covering which may be made of synthetic rubber or the like. This covering is in the form of a two-ended strip, the peripheral ends being separated from one another to define a gap 81. If desired, more than one strip may be used. Preferably the covering 80 is secured to a thin metal backing plate 82 by vulcanizing or the like, the ends of the plate being anchored to the form roller by means of pins 83 or by other suitable means. Interposed between the metal backing plate 82 and the surface of the form roller may be a layer of packing 84, which may for example, consist of a number of layers of paper. It is one of the features of the present form roller construction that the covering 80 may be readily removed from the form roller and mounted on a corresponding roller in a grinding ji'g for the purpose of grinding or resurfacing the covering material. Since this involves removal of material, a corresponding thickness of packing may be added when the covering is reinstalled in the press in order to establish the original over-all diameter of the form roller. Instead of rubber it will be apparent to one skilled in the art that a resilient rubber substitute may be employed without departing from the invention.

With regard to the mounting of the form roller, bearings 86 may be provided at each end which are bodily movable with respect to the printing press frame, the position being determined by adjusting screws, for example, the adjusting screw 87 shown in Fig. 1. This enables convenient adjustment of the pressure exerted by the form roller against the plate cylinder.

In accordance with one of the more detailed aspects of the invention, the form roller 30 is synchronously driven with respect to the plate cylinder 11 and the diameter of the form roller is so chosen that the gap 81 in the form roller covering coincides, at each revolution, with a gap between the plates 11a, 111) on the plate cylinder. In the preferred embodiment, the form roller 30 has an outer diameter which is substantially equal to the outer diameter of the plate cylinder with the plates mounted thereon. This establishes a condition of congruence between the surface of the form roller and the surface of the plate, cylinder so that at each revolution, a given area on the plate cylinder is contacted by the same and corresponding area on the surface of the form roller. The advantage of this relationship will become more apparent when the operation of the device is later discussed in detail. It will suffice for the present to say that this contributes to the elimination of offset negative images. Where the disclosed diameter ratios are adhered to, ghosting thus tends to be eliminated in two distinct yet cooperative ways. As to the specific mechanism for driving the form roller, this is within the skill of the art and consequently only a diagrammatic showing of driving means is included in Fig. 1. Gears of the type usually employed between plate and impression cylinders may be used between the form roller and plate cylinder.

In order to be able to easily and quickly switch from a condition of direct rotation to a condition of reverse rotation,.the blade assemblies 51-54 are mechanically coupledtogether, for example, as shown in Fig. 4 in which the full line position corresponds to that in Fig. 1 Each of the blade assemblies includes an operating arm as designated by the subscript a. On the left hand side, these arms are connected by means of a vertical link 91 and on the right hand side by a vertical link 92. A cross connection is provided by a horizontal link 93 connected at its ends to arms 52b, 54b on the

assemblies

52, 54 respectively. The construction may be repeated at both sides of the press. A manual operator or lever 94 is coupled to the linkage as shown, and it will be apparent that when this lever is swung downwardly into the dotted position, all of the blade assemblies are rotated counterclockwise. This disengages or silences the

assemblies

51, 52 while causing the

assemblies

53, 54 to be activated by inward swinging of their blades against ink rollers 43, 44 respectively. In the discussion of the operation which follows, it will be assumed that the mechanism is in the condition shown in Figs. 1 and 4.

It is one of the features of the present invention that roller vibration is not as essential as it is in the case of more conventional mechanisms. However, in the preferred embodiment shown, we provide a novel vibrating mechanism for vibrating all of the ink rollers simultaneously with a single vibration-producing element. For a disclosure of this, reference is made to Figs. 5, 5a and 6. In accordance with this aspect of the invention, all of the vibrating rollers surrounding the form roller 30 are vibrated by a single wobble plate which may be secured to the shaft of the form roller or separately driven and engaging pulleys or the like at the ends of the respective ink rollers. In the present embodiment, the shaft 100 of the form roller 30 has a wobble plate 101 mounted at its end and engaging pulleys 31a35a and 41a45a on the shaft of the respective ink rollers. In accordance with one of the more detailed aspects of the invention, the edge of the wobble plate is convexed, being formed, in cross section, with an involute curve having a profile similar to that vof a tooth in a spur gear, and the pulleys cooperating therewith have straight, V-shaped sides. Moreover, the pitch diameter of the wobble plate preferably corresponds to the diameter of the form roller. This tends to avoid slippage at the pulleys even though the angle of the wobble plate may change with respect to the angle of the shafts of each of the rollers during the rotation cycle. It will be apparent that in a single revolution of the form roller and connected wobble plate, each of the rollers will undergo a complete cycle of vibration. If desired the wobble plates may be separately mounted as shown at 101a in Fig. 5a and driven, for example, by a wobble plate pulley 1011; and belt 1010 coupled to the press drive through a variable speed coupling 101a. In the latter event slippage at the pulleys is inherent and the pulley surfaces will require lubrication. In order to prevent any looseness between the individual pulley elements and the periphery of the wobble plate 101, such pulley elements may be constructed in two parts urged together by a spring as for example, shown in Fig. 5b, the spring being indicated at 42b.

The sockets which mount the ink rollers Cal-35 and 41-45 should be spring-pressed inwardly with respect to the form roller in order to accommodate the adjustment of the form roller toward and away from the plate cylinder, which adjustment has been referred to above. Also the socket should be such as to enable its shaft to be brought outwardly for engagement by the vibrating mechanism, in this case the wobble plate 101. A number of different roller socket designs will meet these requirements, we nevertheless prefer to employ the construction which is shown in Chase Patent 2,774,299,

preferably with suitable provision for locking the roller in position under operating conditions. Desirably, the socket frames are so oriented with respect to the press frame as to permit movement of the rollers radially with respect to the form roller. Use of such sockets has the further advantage that the individual rollers may be thrown off or disengaged simply by operating the manual control lever forming a part of the socket construc tion, thereby to facilitate removal of the blanket from the form roller for replacement or resurfacing.

Very little maintenance is required since the ink rollers 31-45 and 4145 are made of metal. Thus there is only one rubber surfaced, removable and therefore readily renewable, element in the entire inking arrangement and there is no need to remove any of the roller elements, at any time. Also the endwise vibration of the rollers in contact with the stripping blades tends to reduce and equalize any wear thereon so that long life is assured.

With the various structural features of the inking arrangement in mind, attention may next be given to typical operating conditions. It will be assumed, first of all, that the

blade assemblies

51, 52 on the return side of the form roller are in their active stripping position and that the

assemblies

53, 54 on the other side are disengaged or silenced. Suitable drive means are provided for rotating the form roller, plate cylinder, and impression cylinder in synchronism with one another, i.e., at the same surface speed. The feed roller 24 of the ink feeding device is rotated at such speed by a suitable driving connection. A suitable step-down connection is provided for rotating the fountain roller 23 at a substantially slower speed in accordance with the teachings of the above mentioned McWhorter patent.

In operation a film of ink is supplied by the fountain roller, the thickness being controlled by the settingof thickness determined by the blade 25 is constant along the length of the fountain roller and no means need be provided for adjusting the thickness on a column-bycolumn basis. A portion of the ink film on the fountain roller is wiped off by the ridges on the feed roller 24 which is in rolling contact with the form roller 30. The ink applied to the feed roller 24 is formed into a rudimentary film by the pressure of the roller 24 against the rubber surface of the form roller, so that the ink is already in the form of a film when it reaches the ink roller 45. Such roller effects a smoothing or equalization of the film, following which the film passes into contact with the roller 44 where the action is repeated. Further refinement of the film is accomplished by the vibrating

rollers

43, 42, 41 so that the film leaving the roller 41 is almost perfectly uniform along the entire length of the form roller. This ink film is then passed to the raised areas on the plates 11a, 11b. The amount of ink required by the upraised portions of the plates is constant per unit of actual printing area although it will be understood that on the average a greater amount of ink will be removed by a half-tone or solid area than by an equivalent area of text because of the larger proportion of printing area. The ink film is transferred to the web 13, trained about the impression roller, in the usual way.

In order to reestablish a virgin film for the successive revolution of the form roller 30, it is desirable, in accordance with our teachings, to substantially completely remove the film on the return side of the form roller. Prior to removal it is helpful to remove any sharp dividing line between the de-inked areas and the areas containing substantial residual ink and for this purpose vibrating rollers 31, 32 are employed. Consequently, the ink remaining on the form roller at the time that a given area thereon reaches the roller 33 is free of abrupt changes in film thickness. However, the rollers 31, 32 (and 41, 42 as well), are optional and may be omitted if maximum simplification is desired.

When the surface of the roller 33 engages the residual film on roller 30 approximately half of the film is removed and clings to the surface of the roller 33. The amount thus removed may be considerably more than one-half, but for purposes of illustration, it may be assumed that only one-half is removed. The ink picked up by the roller 33 is stripped off by the blade 64 of the blade assembly 51 and drips down into the pan 71. The ink film remaining on the surface of the form roller after it passes the roller 33 is similarly divided between the form roller and the vibrating roller 34, and the ink picked up by such roller is stripped off by the blade assembly 52 and drips into the pan 7!. Thus the result of only two scraping or stripping operations is to dispose of more than of the residual ink. Additional blades may be provided for example, on rollers 31, 32, if a still higher degree of stripping is desired. The small amount of ink which is left on the form roller after it leaves the ink roller 34 has had its pattern substantially obliterated before a fresh film is applied and is therefore of no practical importance.

At the feeding device or fountain a fresh supply of ink is applied and another cycle is begun. It will be apparent that between successive inking operations performed by a given area of the form roller, the residual ink is not only stripped but the remainder is so acted upon that any possibility of ghosting is substantially eliminated. It will be understood also that substantial elimination of ghosting is achieved by the present arrangement even though the preferred 1:1 ratio between the form roller and plate cylinder is not adhered to, although it will be apparent that where the above ratio is not used a continuous covering should be used on the form roller.

That starvation is also avoided by the action of the stripper blades may be demonstrated by assuming that one column on a printing plate consists entirely of solid areas or cuts and an adjacent column entirely of text. Thus a substantial amount of ink will remain on the form roller and have to be returned to the fountain in the lightly inked column position and very little in the heavily inked column position. However, this constitutes no disadvantage in the present device since the returned or residual ink is simply removed regardless of the amount present, more at certain positions along the stripper blade than at other positions, and is not, in any event, carried around into subsequent or repeated contact with the printing plate. Thus contact of the form roller with a printing plate occurs with a substantially uniform and virgin ink film on the surface of the form roller.

Using the above arrangement, it will be apparent that the troublesome operation of adjusting the keys usually required when changing plates is unnecessary. Consequently, plates may be changed and the press restored to operation by a relatively inexperienced personnel with a great saving of time and expense. Using this arrangement it is not necessary to have a large press screw available for the change-over operation. To vary the shade of the printed impression it is not necessary to adjust a plurality of keys as in conventional inking arrangements, it is sufficient to operate only one control, namely, the manual adjustment 26 which adjusts the blade 25 along its entire length. Thus the adjusting means 26 may, for convenience, be referred to as a shade adjusting means.

It will be apparent that when it is desired to reverse the direction of rotation of one-half of the press unit as required for color printing, the only change-over required in the inking arrangement is the switching of the linkage from the solid to the dotted positions in Fig. 4, the device being capable of operating just as efiiciently in one direction as the other.

We claim as our invention:

1. In a printing press the combination comprising a plate cylinder having provision for attaching plates thereto, an impression cylinder cooperating therewith, a single form roller in rolling contact with the plates on said plate cylinder and having a feed side and a return side. a first series of ink rollers in rolling contact with said form roller on said feed side, a second series of ink rollers in rolling contact with said form roller on the return side. an ink feeding device for feeding ink in thinly distributed form to said form roller between said first and second series of ink rollers, at least a portion of said ink rollers on the return side of said form roller having stripper blades extending along the length thereof for stripping off the residual ink left on the form roller following contact thereof with the plates on the plate cylinder.

2. In a printing press the combination comprising a printing cylinder having provision for attaching printing plates thereto, an impression cylinder for cooperating with said printing cylinder, a single form roller in rolling contact with the plates on said plate cylinder and having a feed side and a return side, a first series of ink rollers spaced about the periphery of said form roller on its feed side, a second series of ink rollers spaced about the periphery of said form roller on its return side, an ink feeding device for feeding ink to said form roller between said series of ink rollers and at a point remote from said plate cylinder, means associated with at least a portion of the ink rollers on the return side for stripping off the ink film therefrom, said form roller having a diameter equal to that of the plate cylinder with plates mounted thereon, and means for driving said cylinders and said form roller at the same surface speed.

3. In a printing press the combination comprising a printing cylinder having provision for attaching plates thereto, an impression cylinder cooperating therewith, a single form roller in rolling contact with the plate on said plate cylinder, ink rollers spaced about the periphery of the form roller on both the feed and return sides thereof, ink feeding means for supplying ink to said form roller faces-pas in thinly distributed form along a line on said form roller opposite the region of contact between the form roller and plate cylinder, means for stripping ink from at least a portion of the ink rollers on the return side, said form roller having a removable resilient blanket thereon, means for anchoring the ends of said blanket and defining a joint in said blanket extending the length of said form roller, means for driving said plate cylinder and said form roller in synchronism with one another, the diameter of the form roller being so related to the diameter of the plate cylinder that the joint in the blanket in said form roller falls between the plates on said plate cylinder at each revolution of the form roller.

4. In a printing press the combination comprising a plate cylinder having provision for attaching plates thereto, an impression cylinder cooperating therewith, a single form roller in rolling contact with the plates on said plate cylinder, ink feeding means located substantially opposite the region of contact between the form roller and plate cylinder for feeding ink to the form roller in thinly distributed form, a first series of ink rollers spaced about the periphery of said form roller on one side and in rolling contact therewith, a second series of ink rollers spaced about the periphery of the form roller on the opposite side and in rolling contact therewith, a portion of the ink rollers in each series having stripper blades for stripping the ink film therefrom which is picked up from said form roller, means for driving the cylinders and form roller in forward and reverse directions, and means for silencing the stripper blades on the side of the form roller which feeds ink to the plates and depending upon whether the driving mechanism is rotating in the forward or reverse direction.

5. In a printing press the combination comprising a plate cylinder having provision for attaching plates thereto, an impression cylinder cooperating therewith, a single form roller in rolling contact with the plates on said plate cylinder, ink feeding means located substantially opposite the region of contact between the form roller and plate cylinder for feeding ink to the form roller in thinly distributed form, a first series of ink rollers spaced about the periphery of said form roller on one side and in rolling contact therewith, a second series of ink rollers spaced about the periphery of the formroller on the opposite side and in rolling contact therewith, a portion of the ink rollers in each series having movable stripper blades for stripping the ink film therefrom which is picked up from said form roller, means for driving the cylinders and form roller in forward and reverse directions, and manually operable means for simultaneously (a) advancing the stripper blades into stripping contact with their respective rollers on the return side of said form roller and (b) retracting the stripper blades on the feed side of the form roller.

6. In a printing press the combination comprising a printing cylinder having provision for attaching printing plates thereto, an impression cylinder for cooperating with said printing cylinder, a single form roller in rolling contact with the plates on said plate cylinder and having an ink feeding side and an ink returning side, a first series of ink rollers spaced about the periphery of said form roller on its feed side, a second series of ink rollers spaced about the periphery of said form roller on its return side, an ink feeding device adjacent said form roller between said series of ink rollers and remote from said plate cylinder for feeding ink to said form roller in thinly distributed form across the width thereof, means associated with at least a portion of the ink rollers on the return side for stripping off the ink film therefrom, and means driven from the shaft of said form roller for simultaneously vibrating all of said ink rollers.

7. In a printing press the combination comprising a printing cylinder having provision for attaching printing plates thereto, an impression cylinder for cooperating with said printing cylinder, a single form roller in rolling contact with the plates on said. plate cylinder and having a feed side and a return side, a first series of ink rollers spaced about the periphery of said form roller on its feed side, a second series of ink rollers spaced about the peengaging and simultaneously vibrating the shafts of said ink rollers.

8, In a printing press the combination comprising a printing cylinder having provision for attaching printing plates thereto, an impression cylinder for cooperating with said printing cylinder, a single form roller in rolling contact with the plates on said plate cylinder and having a feed side and a reutrn side, a first series of ink rollers spaced about the periphery of said form roller on its feed side, a second series of ink rollers spaced about the periphery of said form roller on its return side, an ink feeding device for feeding to said form roller at a region between said two series of ink rollers, means associated with at least a portion of the ink rollers on the return side for stripping off the ink film therefrom, a wobble plate alined with the shaft of said form roller, and pulley elements on the shafts of the respective ink rollers for drivingly engaging the edge of said wobble plate, the edge of said wobble plate being convexed and said pulleys being matingly concaved.

9. In a printing press the combination comprising a printing cylinder having provision for attaching printing plates thereto, an impression cylinder cooperatively engaging said printing plates, a single supply roller having a removable resilient covering also cooperatively engaging said printing plates for supplying ink thereto, a device for supplying a uniform film of ink to the entire length of said supply roller, a first series of rider rollers mounted for reciprocating movement in rolling contact with one side of said supply roller between the ink supply device and the printing plates, a second series of rider rollers mounted for reciprocating movement in rolling contact with the other side of the supply roller between the printing plates and the ink supply device, and means for removing residual ink from the entire length of the supply roller following inking contact between the supply roller and the printing plates so that the surface of the supply roller will be substantially free of ink prior to the supplying of the uniform film of ink thereto.

10. In a printing press the combination comprising a printing cylinder having provision for attaching printing plates thereto, an impression cylinder cooperatively engaging said printing plates; a single supply roller having a removable resilient covering also cooperatively engaging said printing plates for supplying ink thereto, a device for supplying a uniform film of ink to said supply roller, a first series of rollers mounted for reciprocating movement in rolling contact with one side of said supply roller between the ink supply device and the printing plates, a second series of rollers mounted for reciprocating movement in rolling contact with the other side of the supply roller between the printing plates and the ink supply device, scraping means adjacent each of said series of rollers respectively and engageable therewith, and means to engage the scraping means associated with one series of rollers while disengaging the scraping means associated with the other series of rollers.

11. In a printing press, the combination comprising an ink fountain having a fountain roller and fountain blade, a plate cylinder, roller means including a form roller and defining an ink supply path for carrying an ink film from said fountain to said plate cylinder for picking up by a plate on said plate cylinder; said roller means also being,

arranged to define an in]: return pathfor conveyingfrom the form roller the residual ink remaining thereon after contact with the plate on the plate cylinder, means including a scraper blade in the return path of said roller means for scraping the residual ink therefrom and for continuously discharging the same clear of said ink supply path, means for mounting the fountain blade for bodily movement relatively toward and away from the fountain roller, and manual shade adjusting means for adjusting the position of the blade mounting means thereby to simultaneously vary the thickness of the ink film along the full length of said fountain blade.

References Cited in" the file of this patent UNITED. STATES PATENTS Hollingsworth' Jan. 14, Wood Aug. 23, Phythian Aug. 14, Wainwright et al. Sept. 1, Wood Aug. 16, Trotter Mar. 17, Frolich Apr. 7, Taylor Nov. 28, Taylor Nov. 18, Meyer et al. Aug. 29, McWhorter Oct. 14,