CA1101731A - Inking mechanism - Google Patents

Abstract

INKING MECHANISM

ABSTRACT OF THE DISCLOSURE
A mechanism for applying ink to a rotating roll in a printing press comprising an ink rail extending along a length of said roll and mounted on a support therefor. The ink rail is removably secured to the ink rail support. The ink rail has a plurality of ink-applying sections spaced axially along the roll. Each section extends circumferentially around a part of the roll. A plurality of individual gear pump and motor units are secured to the ink rail. Individual gear pump and motor units are associated with different ink-applying sections for providing a controlled continuous flow of ink to its associated ink applying section. Ink supply passages are located in the ink rail for directing ink from a supply to the pump and motor units and ink delivery passages are in the ink rail for delivering ink to the ink-applying sections from said pump and motor units

Description

~ ~73:1 ~ACKGROUND AND SUMMARY OF T~E PRESENT INVENTION
, The pre.sent invention relates to a mechanism for applying ink to an ink roll of a printing press. The mechanism is of the type which includes an ink rail which extends partially cir-cumferentially around the roll. A plurality of pumps pump the ink into a position to be picked up by the roll as it rotates relative to the ink rail. Each pump delivers ink to a circum-ferentially extending portion of the roll which corresponds to a column on the page to be printed. Numerous prior art patents disclose such inking mechanisms. Typical of such patents are U.S. Patents 3,018,727; 3,134,326; 3,400,658 and 2,672,812.
Known ink rail designs are relatively cumbersome in con-struction and heavy. This is due to the fact that commonly piston-type pumps are used which have a stroke adjustment for purposes of adjusting the amount of ink which is delivered to the roll.
Because of their weight, the pumps are commonly mounted off the ink rail which is generally manually removable from the press. Thus, relatively long conduits, or hoses and fittings, are necessary to deliver the ink to the roll.
; In addition, piston-type pumps, even if mounted on the ink rail, deliver a pulsing flow of ink to the ink roll rather than a continuous even flow of ink. Also, the stroke adjustments are cumbersome, and xelatively complicated mechanisms are involved.

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Another disadvanta~e o~ known ink rai1 cQnstructions is that a bead o~ ink tends to collect at the end of the ink rail, and that periodically t~i~s ~ead ~f ink will release ~rom the end of the ink r~ nd ~e c~rri~ed thr~u~h the ink~ng train.
As a result/ periodically an ~xcess~o~ ink ~low~ through the ink train and an advers~ effect on the quality of the printing occurs.
In accordance with the present invention, a substantial simplification in structure is achieved along with improved inking of the roll. A plurality of ink pumps is associated with an ink rail and specifically are mounted directly on the ink rail. The ink pumps preferably are gear pumps, each having a D.C. motor associated therewith, and which, when operating, provide a continuous output flow of fluid. Each gear pump delivers ink to a particular section of the ink rail from which the ink is then applied to a particular circumferentially extending segment of the ink roll corresponding to a column on the page to be printed. By controlling the speed at which the motor operates, the amount of ink pumped can be varied and thus the amount of ink delivered to the roll can be varied. The motor speed can be controlled in any suita~le manner to provide accurate ink feed flow rates.
A plurality of gear pumps and motors are mounted in a spaced relation along the ink rail. Each pump has an inlet passage in the ink rail and an outlet passage also in the ink rail. The porting for the gear pump is face-type porting with the inlet and outlet passages in the ink rail intersecting a face of the ink rail against which the gear pump is assembled.

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Further in accordance with the pres,ent invention, the. ink.
rail with the gear pumps and D.C. motors secured thereon, are supported on an ink rail support and may be manually remove.d from the ink rail support. The ink. rail is remova~ly secured to the ink rail support by a plurality of fasteners. ~he~
released from the ink rail support, the ink rail, along with the pumps and motors, may ~e removed as~ a unit, since the assembly is relatively light weight.
Also in accordance with the present invention, the various gear pumps are assembled in so-called page packs, each of which correspond to a page being printed in th.e print;ng press. Each page pack has a valve for delivering the same fluid to all c the gear pumps of the page. pack. Along each inking roll there may be a plurality of page packs so that a plurality of different colored inks could be applied to the same roll at the same time. The valve associated with each page pack may be adjusted to deliver black ink to all of th.e gear pumps of the page pack, or to deliver colored ink to all of the gear pumps.
of the page pack. ~lso, for purposes of cleaning th.e ink.
roller and gear pumps, a cleaning solvent may be delïvered through th.e valve to the ink roll~ Accordingly, the valve has three inlets and one outlet ~hich.communicates: with th.e gear pump through pas~ages in the ink rail~
A problem which may be encountered when feeding s:everal pumps from a single manifold conduit in the ink rail i5 starvation of those pumps remote from the ink inlet to the single manifold conduit. To overcome th.is problem a preferred embodime~t of the invention includes a large manifold chamber 73~

connected to the ink supply and individual conduits extending from the manifold chamber to each pump.
Further, the output of each gear pump is directed through an orifice located adjacent to the periphery of the ink roll.
As the roll rotates past the orifice, ink is r pped out of the orifice and essentially is accelerated from zero speed to press speed. This action is believed to result in a heating of the ink and is believed to be a direct cause of the buildup of ink at the end of the ink rail in the prior art structures. It has ~een discovered that by providing a recess in the ink rail adjacent to the roller and which recess is located downstream of the orifice, the collection ink at the end of the ink rail ïs substantially minimized. It is believed that the recess gives the accelerated ink a chance to cool after it has been ripp d from the orifice by the roll. As a result of this cooling, it has been found that buildup of ink on the end of the ink rail is minimized.
Experiments have shown that the average ink volume requirement on each column of a newspaper at a minimum press speed of 5Q0 ft/min. is in the range of from 2-8cc of in~/minute. For commercial application, flow requirements may ~e as low as Q.l cc/min. per pump. Only one pump on the page pack of 8 pumps may be running at such a delivery rate. Others may be off entirely or running at a higher rate. The range required for commercial use is from 0.1 to 60 ccJmin. Under --such extreme requirements, a further pro~lem occurs with D.C.
drive motors for the pumps. With common D.C. motors driving the gear pumps for feeding the ink, the lowest reasonable speed is about 500 RPM. Below this value, the motor stalls or runs erratically and control is lost.

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-5a-D.C. motors normally require a certain minimum voltage in order to begin running. To achieve the required range of ink delivery, accommo-date variation in press speed on commercial offset presses, and provide minimum starting voltage, a pulsing circuit has been devised. Pulses of a predetermined width energize the motors, and the number of pulses per unit time is controlled by a press speed responsive voltage control oscillator.
Each ink pump has, therefore, individual control as well as page control to increase or decrease ink supplies by 8 individual pumps normally feeding one printed page per block. Separate power supplies are desirably used lC for the pump drive and for the electronics to avoid noise spikes in the electronics.
Stated broadly, the present invention provides a mechanism for applying ink to a rotating roll in a printing press, said mechanism compris-ing an ink rail extending axially of said roll, said ink rail having ink delivery and supply passages therein, means for supporting said ink rail in ink delivering relation to said rotating roll, said ink rail including a -plurality of axially spaced ink delivery stations, each of said stations including an ink applying section extending circumferentially around a part of the roll, respective delivery pumps mounted on said ink rail at each of said ink delivery stations, each of said delivery pumps comprising means for ; receiving ink from a supply passage in said ink rail and forcing ink through a delivery passage in said ink rail to said ink applying section for pickup by said rotating roll, individual electric motors for driving each delivery pump, said electric motors being mounted with said delivery pumps on said ink rail, and means for controlling the speed of each motor for each pump to provide a flow of ink from each pump independently of the flow from every other pump so that different amounts of ink may be applied to different axîally spaced areas of said roll.
The invention will now be described in greater detail with refer-ence to the accompanying drawings in which:
Fig. 1 is a view partially in section and partially broken :, illustrating a mechanism embodying the present invention;
Fig. 2 is an enlarged view taken approximately along the line 2-2 of Fig. l;
Fig. 3 is an enlarged fragmentary view of a portion of the struc-ture shown in Fig. l;
Fig. 4 is a sectional view taken along line 4-4 of Fig. 3;
Fig. 5 is an enlarged view taken approximately along the line 5-5 of Fig. 2;

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Fig. 6 is an enlarged view of a portion of Fig. 2;
Fig. 7 is a view taken on the line 7-7 of Fig. 6;
Fig. 8 is a schematic fluid circuit illustrating a system embodying the present invention.
Fig. 9 is a view in partial cross-section like Fig. 6 showing an improved embodiment of the present invention;
Fig. 10 is a cross-sectional view of the ink rail as it appears in the plane indicated by the line lO-10 in Fig. 9;
Fig. 11 is a cross-sectional view of the ink rail and pump assembly as it appears in the plane indicated by the line 11-ll in Fig. 9;
Fig. 12 is a view partially broken away of a plurality of ; ink pumps of the present invention; and Fig. 13 is a block diagram of an ink pump pulsing circuit used in the present invention.
Descri tion of The Preferred Embodiments ~ P - : .
As noted hereinabove, the present invention relates to an inking mechanism for depositing ink on a roll of an ink train of a printing press. Specifically r the present invention ~
relates to the type of mechanism which is termed an ink rail in -which ink is pumped into a rail which extends circumferentially .
around a portion of the ink roll. The roll strips the ink from the ink rail as the roller rotates.
The present invention in particular provides an ink control module which is o a page pack size and is of a compact and unique design. It is constructed to enable easy and 3~L

accurate column control of ink either by manual or automatic control. It is relatively easy to maintain, has minimum hoses and fittings and has an automatic clean and purge system associated therewith. The present invention may be embodied in different specific structures and the preferred embodiments illustrated and described below are merely representative of the present invention.
As shown in Fig. 1, the present invention is used to deliver ink to an ink roll 10 forming a part of an ink train of a printing press. The structure illustrated in Fig~ 1 is a conversion unit applying the present invention to an existing printing press. As a result, the roller 10 is driven from a motor 11 through a timing belt 13. The roller 10 could be driven from the gearing of the printing press but since the illustrated embodiment is a conversion unit for a printing press, a separate motor 11 is provided for driving the roller 10. The roller 10, of course, is in ink-transferring relationship with other rollers (not shown) in the ink train of the press, which rollers deliver ink to the plate cylinder of the printing press. The roller 10 commonly would run against a vibrator roll in the inking train.
The roller 10 is supported at its ~ppo~Xte ends Xn bearing~
14, 15 ~hich are located in arm~ 16, 17, respecti~ely? ~5 s~own in Fig. 1, arm 16 is located on the left side of the roller 10 and extends downwardly and is suita~ly ~ixed at its lower end to a frame member 20. The arm 17 likewise extends 73~L

downwardly and also i5 fixed at its lo~e~ e.nd to the frame number 20. The inking mechanism for applying ~nk to the roller 10 includes an ink rail support or bridge, generally . designated 25. The ink rail support is located between the arms 16 and 17. The ink rail support 25 carries or supports a plurality of ink rails or page pack assemb.lies generally designated 26. The page pack assemblies 26 are supported in longitudinally spaced relation along the length of the roller 10.. Each.page pack assem~ly 26 is remova~.ly se:cured to th.e upper sur:face of the support rail 25 by a plurality of bolts ~ -28 Ish.own.sch.ematicallyl. Removal of the bolts. 28 e~ables ~ :
the entire page pack assem~ly to ~e manually lifted from the ink rail supp~rt 25.
When the page pack assemblies 26 are located and secured to the ink rail support 25, the page pack assemblies and support may be manually moved toward and away from the ink roll 10.
Pre~era~ly, for this purpose a handle 30 is located at each axial end of the roller 10. Only one handle 30 is illustrated in the drawings on the left side of the roller 10. The handles 30 are fixedly connected to stub shafts 31, 32. The stu~ shafts 31, 32 are rotatably supported in openings in the arms 16, 17, respectively. Movement of the handles 30 es-ults in the shafts 31, 32 rotating about their axes relative ~; to arms 16, 17. The shafts 31, 32 are fixedly connected to the ink rail support 25 and upon movement of the handles 30, the ink rail support 25 will pivot about the axis of the stub shafts 31, 32.

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The ink rail support 25 may ~.e secured ~in any position in which it is pivoted ~y means of suita~le fastening arrangements, designated 4a and located at opposite axial ends of the roll 10. Only the fastening arrangement 4Q at the left end of roll 10 is illustrated in detail on the drawings and will ~e descri~ed. T~e fastening arrangement 40 at the right end of the roll is of identical cons,truction.
The fastening arrangement 40 comprises a pin 41 which extends through a hole 43 in the arm 16 and into a curved slot 42 in support 25. The slot 42, best shown in Fig. 2, has a curvature with the center of the pin 31 being the center of the curvature. The pin 41 is threaded at one end and a threaded locknut 44 engages the pin 41. By threading the nut 44 into engagement with the pin 41 r the ink rail can ~e secured in any given position as desired. From the a~ove, it should ~e apparent that upon loosening of the locknut 44 and movement of th.e handle. 3Q, the various page pack assem~lies mounted on the ink.rail support 25 can ~e moved toward or away from the ink roll lQ. This mo~ement being permitted by the fact that th.e pin.41 is located in the slot 42 in the arm 16 and thus does .~ not interfere with such movement~
: A suitable stop arrangement generally designated 50 is provided on ~oth sides to prevent excessive movement of the ~, page pack assem~lies toward the roller 10. The stop arrangement Csee Fig. 4~ comprises a stop screw 51 which has a stop surface 52 for engagement with a surface of the arm 17.

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The stop screw 51 is mounted a~d ~ecured to an L~shaped plate 53 which has one leg of the L ~olted to the ink rail support 25. The stop screw 51 is threaded ~nto the other leg of the L.
~ hen the ink rail support 25 moves toward and away from the roller 10 and the plate 53 and stop screw l~kewise move.
When the surface 52 of the stop screw 51 engages the arm 17 movement stops. It should be clear ~y- adjustment of screw 51 the inwardmost position of the page pack assemblies can be adjusted.
Each of the page pack assemblies 26 încludes an ink rail portion 60 which is curved to the circumference of the roller 10 and carried by a manifold portion 65. The ink rail portion 60 has a plurality of circumferentially spaced passages 61 which are formed in the ink rail 60 and are curved around the periphery of roller lQ. The passages 61 are adapted to receive the ink as will be apparent from the description hereînbelow.
Ink is delivered to the passages 61 through an outlet passage 70~ in the in~ manifold 65 from a gear pump 62 driven by a D.C.
motor 63.
A plurality of gear pumps 62 is provided in each page pack. Each gear pump has an outlet passage 70.
Each outlet passage 70 (see Fig. 2~ communicates with a horizontally extending passage 80. The flow in the passage 80 is divided by a flow directing wedge 80c tFig. 5) which directs t~e flow into two flows indicated by arrows 80a, 80b in Fig.
5. These flows are received in orifices 81, 82 located adjacent to the periphery of the roll 10. The roll 10 as it 7~

rotates past orifice 81, 82 rips the ink ~rom the orifices 81, 82 and accelerates the ink flow from zero to press speed and carries the ink into the passageways 61. The wedge 80c extends circumferentially around the roll 10 and the ink delivered through orifices 81, 82 becomes- deposited on the roll lQ in spaced strips. The vibrator roll in the ink train (not shownl acts to spread the ink longitudinally so that a film of ink is provided throughout the roll.
Each horizontally extending passage 80 has a portion 80d located below the level of the orifices 81, 82 as best shown in Fig. 2. This portion 80d acts as a reservoir and pressure compensator and minimizes "bleeding" of ink onto the roll 10 if the press is stopped.
As noted hereinabove, the ripping of the ink out of the orifices 81, 82 results in a substantial heating of the ink.
The i~k tends to adhere equally to the fast moving ink roll 10 and the ink rail surface and is split, with part of the ink ~ ing with the roll and part moving up the ink rail surface.
These actions also result in ~urther heating of the ink making it qu~te fluid. In particular, the ink immediately adjacent to the ink rail surface is particularly subjected to heating due to friction ~etween the ink and the rail surface. This has resulted in the past in this fluid portion forming a bead at the end 74 of the ink rail 60. This bead gradually increases in size until large enough and cooled enough to stick to the roller. When this bead releases from the ink rail 60 an ; excessive amount of ink flows through the system and a dark ~12-.

spot results on the print. ~'he present invention minimizes this problem by providing a cavity 75 formed in the ink rail and specifically in each of the passages 61. The cavity 75 reduces the formation of the bead on the leading end of the ink rail. Th~s is believed to be due to the fact that the ink can cool in the cavity 75. As a result, the pro~lem of a head of ink releasing from the ink rail and moving down through the ink train is avoided ~y the present invention.
The ink manifold 65 of each page pack assembly has the gear pumps 62 supported thereon. 5pecifically, the gear pumps 62 are supported on a surface 66a of the manifold 65. The manifold 65 of the embodiment shown in Figs. 2 and 6 has a common inlet passage 65a ~hich extends axially through the manifold 65. The common inlet passage 65a is adapted to receive ink from a suitable supply. A sùitable valve 100 controls the flow of fluid into the common inlet passage 65a.
Inlet passageways 71 communicate with the common passage 65a and also communicate with the inlet of respective gear pumps 62. The gear pumps 62 draw ink from the inlet passageways 71 and force ink into the outlet passages 7~.
As noted above, each gear pump 62 is mounted on a face surface 66a of the ink manifold 65. In particular, the inlet passages 70 and outlet passages 71 intersect the face 66a of the manifold 65. A port plate 90 for each gear pump 62 (see Fig. 7) engages the face 66a and ports fluid into and out of the pumping chamber of each gear pump 62. The port plate 90 includes an i~let port 91 and an outlet port 92. The pumps 62 3~L

and port plates 91 ~re ~xedly se~ured on the face 66a of the manifold 65. Each pump 62 has its individual drive motor 63.
Associated with each page pack 26 is- a valve 1~0 which controls the flow of fluid into the common passage 65a of each page pack. The valve 100 is face mounted on the rail support 25. The valve has three inlets, llQ, 111, 112 and one outlet, 114. The outlet 114 is adapted to communicate wit~ a vertically extending passage 101 in the ink manifold 65 to deliver ink or fluid to the common passage 65a. The valve is face mounted on the face 1~2 ~f the rail support 25 ~hich has a pas-sage 10~3 communicating with the passage 101 in the ink manifold 65.
The inlet 100 (see Fig. 8~ is in fluid communication with a supply 120 of black ink. The inlet 111 is in fluid communication with a supply 121 of colored ink. The inlet 112 is in fluid communication with a supply 122 of cleaning solvent.
Each valve lQ0 has a movahle part 125 which can be moved to different positions in order to communicate either inlet to the outlet. The part 125 may be manually moved,a handle 126 ~eing provided therefor. Also, the part 125 may be moved by a suitable stepping motor not sh~wn, Fig. 8 illustrates a system embodying the present in~ention for a blanket to blanket perfecting press having upper and lower plate cylinders and thus upper and lower inkers. The inker for the upper and lower printing units are designated top and bottom. As shown therein page pack ~L9L~i~731 assemblies 26 four in number are associated with the upper inking roller lQ and a plurality of page pack assemblies designated 26a are associated with the lower inking roller designated lOa. A valve lO0 is associated with each page pack assembly and may be set to direct black ink to each page pack assembly or may be set to direct colored ink to each page pack assembly. For example, in the position of the valves lO0 illustrated, the valve is directing black ink into the page pack assemblies.
As shown in Fig. 8 the inlet port 110 communicates with the black ink supply 20 through conduit designated 130.
Upon movement of a valve to a position where the inlet communicates with the outlet 114 the page pack assembly would then receive ink from the colored ink reservoir 121. Further by moving the valve to a position ~here the outlet 114 communicates with the inlet 112, cleaning solvent from the cleaning solvent reservoir 122 is directed through conduit ~3 into the page pack assembly to effect a cleaning thereof.
The ink rail assembly includes means defining a trough 13Q. The trough receives solvent that runs off of the roll lO
during cleaning of the roll.
In Figs. 9-12 there is shown another embodiment of an ink ; rail of the present invention. A~ indicated above, a problem sometimes encountered with a single manifold line, e.g. the line 65a in Fig. 5 feeding several pumps, is starvation of certain of the pump units. ~pecifically, a pump unit remote 1$~3~731 from the ink inlet to the line may not receive a sufficient amount of ink because the other pumps draw off the ink before it reaches the remote pump.
To overcome this difficulty manifolding such as shown in Figs. 9-12 is used. In general, a central manifold is provided with individual conduits leading to individual ink pumps.
Thu~, the fluid pressure at entry into the individual conduits is close to the same for each pump, and no pump is starved.
A$ shown in FigO 9, an inlet flow control valve 150 has a main inlet 152 for, say, black ink. A second fluid inlet 154 is conveniently provided for solvent ~utilized in cleaning the ;`nk rail and pumps~, or for the substitution of a different color ink as described in connection with Fig~ 8. The ;~
directional valve 150 is adapted for manual operation by a throw handle 156. The outlet from the valve 150 opens into a central manifold chamber or reservoir 158, in the ink rail 159.
Manifold chamber 158 is provided with eight outlets, e~g.
16~ 1, 162, 163, 164, 165, 166 and 167. The eight outlets communicate with eight individual ink pumps of a page pack.
Each of the outlets 160-167 communicates with a respective individual con~uit 168-175 extending from the manifold chamber 158 to the individual ink pumps. Specifically, the opening 160 communicates with a series of internal bores in the ink rail defining a conduit 168; opening 161 communicates with conduit ~ -16~; opening 162 communicates with conduit 170; opening 163 communicates with conduit 171 etc. Each of these conduits is connected with a respective pump.

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The manifold chamber 158 ~.~ desira~.ly centrally located on the ink rail 159. The isolated conduits 168, 169, then, are conveniently of the same length and lead to the opposite ends of the ink rail 159. Conduits 170, 171 are likewise of equal length. albeit shorter than conduits 168, 169. The outlets of the conduits 168-175 are on the face 176 of ink rai.l 159 and are uniformly spaced and locate.d for entry of ink or solvent issuing therefrom into the inlets of respecti~e ink pumps, only six pump~ being sho~n and desiynated 18Q-185. It will be understood that an individual i.nk pump i5 pro~ided for each column, and that the number of columns usually 8 to a page pack is a matter of choice.
Also provided in ink rail 156 are individual bores or feed conduits communicating the pump outlet with a horizontally : extending passage 8Q as in the embodiment of Fig. 6. The outlets shown in the drawings are designated 186, 187, 188. .
: The other outlets are not shown.
The ink pumps, e.g. pumps 180.-185 are face mounted on th.e face 176 of ink rail 156 with. their inlet and outlet ports in juxtaposed regi~try with the conduits in the ink rail. Th.e pump inlets communicate with a respective passage 168-175. and the pump outlets communicate with passages such.as 186-188, ; Thus, e.ach pump is provided with.its own supply of ink from a common manifold chamber 158 and delivers ink through a feed conduit having the same length as every other feed conduit. A
pump that is running at a relatively high speed due to high ink demand will not now cause ;nk starvation ~or an adjacent pump~

~L~73~a Better delivery of ink i5 o~talned in this way resulting ;n ~etter in~ control, particularly at the ends of the ink rail.
The speed o~ each ink pump motor is individually controllable and the quant;ty of ink delivered for any given printed column can be adjusted in accordance with the ink desired for that column by adjusting the speed of the motor.
This adjustment can be made automatically or manually~ Still further, as the speed of the press varies, the amount o~ ink supplied a given pump may ~e varied in direct linear proportion.
As noted hereinabove, the flow demands on the gear pumps exter.d over a wide range. When it is desired to provide a very low flow rate from a gear pump, there is a tendency for a D.C.
motor to stall. In order to avoid any stalling of the motor at lower rpm's and still provide for a continuous output from the gear pump, a pulsing circuit, as shown in Figure 13, is preferably utilized for driving the individual motors for the pumps.
The pulsing circuit is constructed so that each motor is energized by periodic pulses for a constant period so that its pump, during each period, delivers a predetermined constant amount of ink. Increases or decreases in the amount of ink required from a given pump are provided by controlling the interval between pulses. An arrangement for accomplishing such control and enabling control of ink over a wide range of flow rate is shown in Figure 13.
As shown there, each pump 200 is energized by a drive circuit 202 during the period of a one-shot 205. The one-shot .. . . .. .. .. . .

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is fired at intervals determined by the repetition rate of pulses from a voltage controlled oscillator 207. The input to voltage controlled oscillator 2Q7 is from an individual pump .:
potentiometer 210. The control voltage for potentiometer 210 as well as for corresponding potentiometers of the remaining pumps for the same page pack is provided by amplifier 214. The portion of the control voltage selected by wiper 215 o~ the potentiometer may be determined for each pump individually to esta~lish a ~ase flow rate for that pump in a given run. The input to amplifier 214 is from a page pack potentiometer 217 whlch.may ~e set to provide a common base flow rate signal for the set of eight page pack pu~ps. TKe control voltage to ; potentiometer 217 i5 from the press tachometex 220 and that signal is provided to all page pack potentiometers.
: In operation, potentiometers 217 and 210 will be set according to the requirements for ink flow rate from the block of page pack pumps and the individual pump 200, respectively.
: Voltage.controlled oscillator 207 includes an integrator 223 which produces a ramp signal having a slope proportional to the ~ 20 ~gnal at its output. When the signal reaches a predetermined :~ ~al~e. a Schmitt trigger 225 is fired and discharges integrator ;~ 22.3 as well as ~iring one-shot 205~ The one-shot produces a pulse of predet~rmined time duration to drive motor 200 through ` dri~e circuit 2Q2.
A change in the speed of the press will produce a corresponding change in the output of amplifier 214 and the -19- -.
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input to voltage controlled oscillator 207. This change results in a corresponding change in the repetition rate of .
pulses to one-shot 205 and in the intervals at which motor ~00 is energized.
At relatively high press speeds and/or at key settings requiring relatively high output from a gear pump, the pulses delivered to the arive circuit 202 for that gear pump will be at such a rate that the motor 200 will operate in substantially a continuous manner and will drive the gear pump with which it is associated in a continuous manner, and therefore a continuous flow of ink will flow from the gear pump. At low press speeds and/or key settings requiring a small amount of ink from the gear pump associated with a particular motor, the motor will be operated in a pulsed manner so that the flow from the gear pump with which the motor is associated will be in pulses. However, there will be a sufficient supply of ink for delivery in a continuous manner to the roll so that the proper quantity of ink is supplied to t~e roll.

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Claims (8)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A mechanism for applying ink to a rotating roll in a printing press, said mechanism comprising an ink rail extending axially of said roll, said ink rail having ink delivery and supply passages therein, means for supporting said ink rail in ink delivering relation to said rotating roll, said ink rail including a plurality of axially spaced ink delivery stations, each of said stations including an ink applying section extending circumferentially around a part of the roll, respective delivery pumps mounted on said ink rail at each of said ink delivery stations, each of said delivery pumps comprising means for receiving ink from a supply passage in said ink rail and forcing ink through a delivery passage in said ink rail to said ink applying section for pickup by said rotating roll, individual electric motors for driving each delivery pump, said electric motors being mounted with said delivery pumps on said ink rail, and means for controlling the speed of each motor for each pump to provide a flow of ink from each pump independently of the flow from every other pump so that different amounts of ink may be applied to different axially spaced areas of said roll.

2. A mechanism as defined in claim 1 wherein each of said delivery pumps includesa port plate having a surface which has an inlet port communicating with a supply passage and an outlet port communicating with a delivery passage, said surface of said port plate being in abutting engagement with a surface of said ink rail.

3. A mechanism as defined in claim 1 further including means supporting said ink rail support for pivoting movement relative to said roll to enable said ink rail to be adjustably positioned relative to said ink roll.

4. A mechanism as defined in claim 1 wherein said ink rail has a manifold chamber located centrally thereof and each of said supply passages communicateswith said manifold chamber and with said inlet port of said delivery pumps,: said supply passages communicating with said manifold chamber at locations spaced radially different distances from the axis of said rotating roll.

5. A mechanism as defined in claim 1 wherein the surface of each of said ink applying sections extending circumferentially around the roll includesa longitudinally extending recess and at least two longitudinally extending margins of said recess define first and second circumferentially spaced gaps with said roll, said recess having a circumferential wall at a slightly greater radial distance from the axis of said rotating roll than said gaps, and into which recess the ink moves after being ripped from said orifice by said roll, and which recess provides a reservoir enabling the ink to cool therein prior to reaching the end of said ink applying section.

6. A mechanism as defined in claim 1 wherein said ink rail has a common inlet passageway therein and said ink supply passage communicates fluid from said common inlet passageway to the inlet of said delivery pumps, and further includes a valve for controlling the flow of fluid into said common inlet passageway, said valve having a plurality of inlets adapted to different fluid supplies and said valve having a movable port for selectively communicating one of said inlets with the outlet of said valve.

7. A mechanism as defined in claim 6 wherein said valve is removably secured to the surface of said ink rail support and remains secured thereto upon removal of said ink rail from said ink rail support.

8. A mechanism as defined in claim 4 wherein said means for receiving ink from a supply passage in said rail includes a delivery pump supply passage having passage portions for direct-ing ink generally parallel and radially relative to the axis of said roll, each of said delivery pumps having an inlet, only one pump inlet being connected with a given delivery pump supply passage.