Abstract:
A printing press having a number of identical inking systems for delivering ink to said press. The individual inking systems comprises an ink source including an ink reservoir held under a positive pressure. The ink travels from the manifold through a valve mechanism and to one or more piston mechanisms which undergo rotary and reciprocating motion, and thence to the ink outlets. Two piston and single-piston mechanisms are described.

Description:
This is a continuation-in-part of my earlier filed Application Ser. No. 10/461,147 filed on Jun. 13, 2003. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to inking systems for printing presses, and more particularly to various adjustable phasing systems for ink valves and ink pumps in series and which adjust the ink flow separately to each column of printing coming from a press. According to various embodiments of the invention, the ink may flow from 0% to 100% of a selected maximum for each column across the web. 
     The manner in which the ink flow is adjustably phased comprises an ink input, a phasing unit or rotary valve for the input, an injector pump unit in series with the phasing unit, and an ink output line which delivers the ink to the roller and then to the paper. One advantage of this system is that no return is made of ink which is not used; some systems pump a certain amount of ink, and this amount is divided into one portion that flows to the paper while the remainder of the ink is returned to the reservoir. Another system of the invention uses a single rotary piston with two flats, spaced axially along its length and an adjustable barrel plus appropriate passages in the barrel housing. This system uses an open yoke to allow the piston to have an intermittent motion to avoid creating a vacuum in the piston. 
     Known inking systems include piezoelectrically driven ink flow valves which open and close to a degree which is dependent on the need for ink at that time. Owing to the problem of variable flow rate through the valves, these systems require delicate timing, have significant expense and complexity, and have other problems as well. 
     In view of these and other shortcomings of the prior art, it is an object of the present invention to provide several improved, adjustable ink flow control systems and methods. 
     Another object is to provide a plurality of so-called phased injectors for the ink used in a modern offset press, with the injectors being either of the single-piston type, or the two-piston type. 
     A further object is to provide a rotary valve in series with a positive displacement pump for each column of print provided in an offset printing press, whether the pumps are a single member with two flats or reliefs or are two members each with a single flat or relief. 
     Another object is to provide systems in which the ink used flows from the valves to the pumping units or injectors to the press rollers, all without being returned to the ink reservoir. 
     A still further object is to provide, for each column of print, different methods of controlling ink flow using phase control between a rotary valve or barrel assembly and using a positive displacement pump in series with each other. 
     A further object is to provide methods and apparatus having easily adjustable controls for adjusting the effective phase angle between the rotary valve and the positive displacement pumps in a press inking system, whereby the exact amount of ink desired may be delivered to each of the various columns to be printed by the press. 
     A still further object is to provide a system without a return circuit for ink which is not desired to be used. 
     A further object is to provide a system of inking wherein the flow rate in view of the viscosity of the ink can be adjusted for, and in which ink viscosity is ultimately immaterial as far as the correct or desired amount of ink flow is concerned. 
     Another object, in one embodiment, is to take advantage of a rotary valve having a rotary-valve core and a sleeve with intake and outlet ports in series with a positive displacement pump using a reciprocable and rotatable piston and using one such valve and one pump in series for every column of printed matter in the press. 
     Another object of the invention is to provide three different versions of somewhat similar apparatus and which operate in similar but not identical ways, and in which each apparatus ultimately accomplishes a related novel result. 
     A still further object is to provide one embodiment wherein the phase control is accomplished by rotating the valve core in the rotary valve and holding the sleeve in a fixed position. 
     A further object is to provide another embodiment wherein phase control is achieved by means of rotating the sleeves rather than the cores of the rotary valves relative to each other. 
     Another object is to provide a phase control unit wherein one sleeve is inclined relative to its drive input, thereby providing the eccentric motion necessary for piston rotating and reciprocating motion. 
     Another object is to provide an ink supply system wherein the rotary valve and the pumping unit comprises two flats or notches in a single piston rather than two flats or notches in two separate pistons. 
     A still further object is to provide an embodiment of a rotary mechanism which uses an open slot yoke rather than a bearing in a yoke for rotating the piston and allowing slack in the piston movement under certain conditions. 
     Yet another object is to provide a barrel and a having a body with appropriate passages for ink demanded by the rotary valves or pistons. 
     These and other objects and advantages and the manner of their attainment will become more clearly apparent when reference is made to the following detailed description of the invention set forth by way of example and to the accompanying drawings wherein like reference numbers indicate corresponding parts throughout. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     FIG. 1 is a vertical sectional view of one form of printing press showing ink flow through one of many identical inking stations and showing a portion of a fountain roller, a rotary phasing valve, a positive-displacement injector pump and associated clutch and drive gears, an ink inlet line, an ink outlet line, a spreader, and other elements of one embodiment of the invention; 
     FIG. 2 is an enlarged view of a rotary ink valve including the sleeve which is movable about its cylindrical axis and an ink injector pump in the embodiment of FIG. 1; 
     FIG. 3 is an exploded perspective view of the rotary valve of FIG.  1  and the injector pump, a portion of the yoke and valve core drive and the housing for these parts; 
     FIG. 4 is a schematic vertical sectional view, taken along lines  4 — 4  of FIG. 2, showing the cylinder, valve, core and piston of FIG. 2 in one position; 
     FIG. 5 is a schematic vertical sectional view of parts of the core and piston, taken along lines  5 — 5  of FIG.  2 . 
     FIG. 6 is a view of the elements schematically shown in FIG. 4, only showing the components in a different position; 
     FIG. 7 is a view similar to FIG. 5, but showing the components in another position; 
     FIG. 8 is a greatly enlarged horizontal sectional view of the piston of FIG. 7 in one position thereof; 
     FIG. 9 is a schematic view similar to FIGS. 4 and 6, showing another position of the components; 
     FIG. 10 is a view similar to FIGS. 5 and 7, showing the components in still another position; 
     FIG. 11 is a horizontal sectional view of the piston similar to FIG. 8, only showing the piston in a different position; 
     FIG. 12 is a vertical sectional view of a modified version of the ink pump of the invention; 
     FIG. 13 is an exploded prospective view of the inking apparatus of FIG. 12, showing a single piston with two flats cut into the piston on opposite sides thereof and showing the moveable barrel, the barrel retainer, the valve body including the bore and various passages, the phasing gear and the drive mechanism for the pistons, including the open yoke; 
     FIG. 14 is an end sectional view of the ink inlet passage of FIG.  12  and one position of the piston showing the beginning of the fill cycle, taken along lines of A—A of FIG. 12; 
     FIG. 15 is an end sectional view of the transfer of passage and the piston of FIG. 12, taken along lines B—B of FIG. 12; 
     FIG. 16 is an end sectional view of the transfer passage at outlet passage and piston of FIG. 12, taken along lines C—C thereof; 
     FIGS. 17-19 are figures similar to FIGS. 14-16, showing the end of the fill cycle; 
     FIGS. 20-22 are views similar to FIGS. 14-16, but showing the beginning of a half flow fill cycle, and 
     FIGS. 23-25 are views similar to FIGS. 20-22, but showing the end of a half flow fill cycle. 
    
    
     DETAILED DESCRIPTION 
     Although the invention may be embodied in various forms, a description will be given of several forms of the invention, all of which allow adjustment to be made individually of the quantity of ink delivered to each column of an offset press. These are typically six or eight columns each, for a page to be printed by a module of the inking system of the invention. With four pages, therefore, there are 24 to 32 modules, each of the type described herein. In one instance, the sleeve or cylinder of the rotary valve upstream (as the ink flows) of the piston may be rotated to a variety of positions, thus varying the ink flow from 0% to 100%. In another embodiment, the core of the rotary valve is advanced or retarded relative to the cycle of the piston on the injector pump, thus altering the flow between 0% and 100%, and all percentages there between. In still another form, a single piston having two flats or cutouts is used with an appropriate cylinder block and passages, and with phasing controls for the ink supply. 
     In one typical embodiment, the present invention consists of an inking system for a multi-column printing press. The apparatus typically includes an ink or fountain roller which is one of many rollers (not shown) and an ink spreader, which is the last component upstream of the fountain roller. In another embodiment, the overall results are the same, but the mechanism of delivering the ink is different. 
     Referring now to FIGS. 1-11 of the drawings in greater detail, there is shown in FIG. 13, certain elements of a printing press generally designated  20  including several rollers  22  (only one shown) a spreader generally designated  24  and upper and lower members  26 ,  28  between which is the ink orifice  30 . In addition, there is shown a flex hose  32  leading to the spreader  24  and taking ink from an outlet passage  34  in a cylinder block generally designated  36 . The block  36  also includes an intermediate or transfer passage  38  and an inlet passage  40  which is connected to an ink manifold  42  serving a number of identical stations generally designated  44 . The ink supply contained in the manifold  42  is kept under a moderate pressure, say 20-40 psi, which remains effective throughout the operation of the press  20 . This arrangement therefore insures that the ink will flow through the various passages, valves, etc. whenever they are open. 
     A principal component of an injector pump generally designated  46  which resides in bore  47  is a cylinder  48  having one closed end  54 , an inlet port  50  communicating with the transfer passage  38  and an outlet port  52  communicating with the outlet passage  34 . 
     The piston  56  moves with both a reciprocating motion and a rotary motion and includes a top surface  58 , a notch  60  chordwise of the piston  56  and a lower end  58  with a yoke pin  61 , connecting the piston  56  to the yoke  62  through a ball unit  64  held in the arm  66  of the yoke  62 . The yoke arm  66  is offset by a portion  68  and a rotary, driven extension  70 . The extension  70  has a gear  72  designed to mesh with and be rotated by a gear  74  which drives a rotary valve core shaft  76 . An offset gear  77  takes the driving force and rotates the valve core shaft  76  on which the gear  74  is positioned. This supplies the force to the gear  72 . A clutch arrangement generally designated  78  is provided so that if there is an unintentional stopping force applied to one shaft or gear, forces will not be transmitted to the other gear. The squared off extension  104  enables the valve core shaft  76  to be turned by hand, if necessary. 
     The rotary valve core shaft  76  includes a cylindrical head portion  80  and a notch  82 . The valve core shaft  76  rotates within a contoured cylinder generally designated  84  which is held in place in a bore  85  within the block  36  by a pair of snap rings  86 ,  88 . There are at least 3 O-rings  90 ,  92 ,  94  surrounding the cylinder  84  and sealing it against leakage. These are necessary because of relative movement between cylinder  84  and the block  36  The end portion  96  of the cylinder  84  is squared off so as to receive a driving force from drive motor  106  (FIG. 1) for the cylinder  84 . The cylinder  84  is preferably driven by the motor  106  (FIG. 1) having a shaft  108  driving a timing belt or timing chain pulley  110  which engages a belt or chain  1112  acting on a pulley  114 , which is keyed or otherwise attached to the squared-off portion  96  of the movable cylinder  84 . 
     An important feature of the invention is that the cylinder  84  can be rotated to a limited extent within the block  36  so as to be in phase, partially in phase, or out of phase with the injector pump  46 , thus achieving the phase control in question and which will be illustrated in detail later. The expressions “in phase”, “out-of-phase” or the like relate to the rotation of the rotary valve/cylinder with the counterpart piston. Thus, if the rotary valve and piston are exactly synchronized, the piston/valve are said to be “in phase”:. If there are differences, the two are, to a greater or lesser extent, “out-of-phase”. With the maximum out-of-phase condition, no ink is admitted to the piston; with any degree less that completely “out-of-phase”, the piston takes on a corresponding amount of ink, varying from none or almost none to being filled completely. 
     The cylinder  84  includes an inlet port  98  which communicates with a circumferential groove  100  in the valve core shaft  76 . The groove  100  communicates with the port  98  which in turn communicates with the passage  40  and the ink supply generally designated  42  (FIG.  1 ). The cylinder generally designated  84  also includes an outlet port  102  communicating with the transfer passage  38 . 
     The preferred drive system for the valve core shaft  76  and the piston  56  occurs by way of a motor or the like (not shown) which drives the gear  77  and hence the valve core shaft  76 , with the valve core shaft  76  in turn driving the injector pump piston  46  through the gears  74 , 72 . 
     Referring now to FIGS. 4-11, a plurality of cycles are shown, with the ink and valve in various positions. FIG. 4 shows ink in the passage  40  passing into and around the groove  100 , and thereafter through the port  98  and into the groove  103  in the valve core  84 . The flat or notch  82  in the valve  84  faces toward the passage  40 . At this time, the injector pump is shown with the notch  60  in the piston  56  facing away from the inlet. There is at this position of the pumps no passage  38  connecting the valve and piston. Hence, the valve and piston are out-of-phase. 
     Thus, FIG. 5 shows the rotary valve notch  82  being full of ink I but not aligned with passage  38 . The injector pump piston is also arranged with the notch  60  facing the outlet port  52 , so no ink can flow from the injector. 
     In FIGS. 6 and 7, the loading cycle is shown. Here the notch  82  on the rotary valve core shaft  76  faces toward the passage  38 , and the notch  60  on the injector  56  faces the notch  82 . FIG. 7 shows the ink passing from these notches  82 ,  60 . At the same time, FIG. 8 shows the piston at its lowermost position, that is, at the bottom of its stroke. However, the notch is still facing away from the passage  52 . When the piston completes its upstroke, the notch  60  will be facing the passage  52 , and the upward movement of the piston will deliver the full charge of ink to the passage  34  and ultimately to the spreader  30 . 
     FIGS. 9-11 show a partial fill in the injector pump  56 . FIG. 9 shows partial filling and FIG. 10 shows there is a phased relationship between the rotary valve and the injector pump. The timing of the events is such that the two notches  60 ,  82  are somewhat in and somewhat out of phase. FIG. 10 shows this out-of-phase relationship. At the same time, the stroke of the injector pump is such that it less than completely fills the volume in the notch and above the head  58 . Consequently, the injection pump  60  transfers a reduced amount of ink to the spreader and roller. 
     The barrel  84  can be moved in very fine increments, permitting very close adjustment of ink flow. 
     Another embodiment differs from the first embodiment described drive only by changing the phase relationship described by causing the rotary valve to pass into and out of exact synchronism by rotating the valve core of the rotary valve instead of rotating the cylinder in which the valve moves. In this case, the valve stem opposite the clutch end of the core would engage a drive belt or chain, with a clutch  78  being released during this time so as to permit relative movement between the piston  56  and the valve core  80 . 
     Another embodiment is shown in FIGS. 12 and 13, and its functioning is diagrammatically illustrated in FIGS. 14-25. Referring now to FIGS. 12 and 13, there is shown a roller generally designated  200  having ink fed to it by a member of the individual apparatus generally designated  202  of the invention. The ink feed apparatuses  202  each includes a lower block  204 , a spreader  206 , an intermediate member  208  and a top member  210 , defining between the members  208 ,  210  an ink outlet or orifice  212  which is connected to a horizontal ink passage  214 . 
     The horizontal ink passage  214  is one of several in the body or cylinder block generally designated  216 . An important main component of the invention is a rotatable and reciprocable piston  218  in the form of a right circular cylinder having two flats  220 ,  222  therein as well as a drive pin  224  near one end. Besides the piston  218 , the cylinder block also accommodates a rotatable barrel generally designated  226 , having a central body  228  and an end groove  230  for accommodating a barrel retainer generally designated  232 . The barrel  226  fits within the cylinder block generally designated  216  and is able to be rotated by a phasing gear generally designated  234 , to which it is keyed. A groove  260  extends all the way around in the barrel and includes a phasing port or radial opening  262  which admits ink to a greater or less extent, depending on its phase or position, as will be explained later. 
     Reciprocation and rotation of the piston  218  is accomplished through the drive pin  224  which is engaged by a yoke generally designated  235  driven by a shaft  236  which in turn engages a drive gear  238 . The axis of rotation of the shaft  236  is inclined relative to the rotational axis of the piston  218 , to account for both reciprocating and rotary motion. 
     Referring now to the body or cylinder block  216 , this unit  216  has a lower, inlet passage  240 , two vertical transfer passages  242 ,  244  separated by a horizontal transfer passages  246  and a vertically extending outlet passage  248 . The outlet passage  248  communicates with the horizontal passage portion  214  of the ink outlet. 
     Other components include a gear  250  and a drive mechanism including a shaft  252  for rotating the phasing gear  234  and hence the barrel  226 . A drive gear  238  rotates the shaft  236 ; a squared off end  256  enables the shaft to be manually rotated and hence to be set or reset as desired. 
     Referring now to the operation of certain elements of the embodiment shown generally in FIGS. 12 and 13, the operation of these elements is shown schematically in FIGS. 14-25. In FIGS. 14-16, the ink is shown filling the passage  240 , in which it is confined under a slight pressure, and traveling upward until it fills the area defined by the rear flat  222  on the piston  218 . The ink also flows around and fills the circular passage formed by the groove  260  in the barrel  226 . The ink then also flows into and through the passage  242  and the passage  246 . Referring particularly now to FIG. 16, the ink flows from passage  246  to passage  244 , and starts to fill the notch or flat  220  in the piston  218 . The outlet passage  248  is still just free of a new charge of ink at this time. 
     FIGS. 17-19 show the end of the fill cycle, showing the flat  222  in the piston  218  being completely filled and cutting off further flow from the lower passage  240 . FIG. 18 shows the groove  260  completely filled, and FIG. 19 shows the front flat  220  filled with ink and ready to allow ink to flow into the outlet passage  248 ; the next bit of rotation of the piston will cause ink to flow in the passage  248 , and continue to flow until the flat has passed out of registry with the passage  248 . 
     Referring now to FIGS. 20-22, there is shown a position of the barrel which is rotated 90° from its former position. Here the piston flat  222  is just beginning to fill from the passage  240  and the barrel is rotated so as to be in phase with the flat  222 . FIG. 22 shows the flat  220  in position where it is just starting to be filed from passage  244 . 
     FIG. 23-25 shows the end of the fill cycle with the phasing gear set at a one-half fill, or 3 o&#39;clock, position. Consequently, the flat  222  begins to acquire a one-half load of ink. The phasing gear has moved this phasing port  262  to the 3 o&#39;clock position, and FIG. 25 shows the flat  220  taking on half of the maximum fill. Subsequently, this one-half portion of ink will be sent to the outlet port  248 . 
     One key to the operation of this single piston form of the invention is the phasing port  262  and circumferential groove in the adjustable barrel  226 . When the phasing port  262  in the barrel groove  260  is moved to a 180° or straight up position, the intake of ink is completely blocked out, and no ink can flow regardless of the notch positions in the piston. When the port is moved slightly, a small amount of ink may pass because the notch  222  and the barrel are almost completely out of phase. As the phasing port  262  approaches the lowermost position, the barrel and the piston flat are almost completely in phase, and larger amounts of ink are transferred. 
     The single piston version of the ink supply apparatus has one feature that is different from its counterpart. Because the drive arrangement for the piston must accommodate a partial vacuum in the operating cycle when the flat or notch  222  in the piston is not full, the yoke which drives the piston must be free from pulling a vacuum in portions of the cycle. 
     Therefore, the yoke  234  has a closed end  235  and an open end  237 . This allows the drive pin  224  a degree of freedom it would not otherwise have. Of course, the yoke might also have a closed end, but it should not have a bearing or other fixed-position means of restraining the piston. The ink is supplied from a manifold that serves a number of individual inking systems. This ink is always kept under pressure, usually 10-40 psi, although in the case of more viscous inks, the pressure may be as high as about 100 psi. 
     Other elements of the apparatus are known to those skilled in the art. A rotatable knob  270 , for example, is one method of adjusting the gears that move the barrel to an infinite number of positions between fully open and fully closed. This knob  270  is operated either remotely or by hand, depending on the degree to which the ink supply devices are automated. As pointed out, the rotary valve of the first two embodiments perform the same function as the barrel in the later embodiment, namely, the single piston apparatus. Although the two-position embodiment operates on the same general principle, the single-piston embodiment is less expensive and is more reliable. Other advantages are known to those skilled in the art. 
     It will thus be seen that the present invention provides several novel and effective inking system having a number of advantages and characteristics, including those specifically pointed out and others which are inherent in the invention.