Patent Publication Number: US-6220160-B1

Title: Ink feeding system and method for a printing, duplicating or like machines

Description:
FIELD OF THE INVENTION 
     This invention generally relates to the art of printing or duplicating machines and, particularly, to a system or method for feeding ink to an ink fountain of the machine. 
     BACKGROUND OF THE INVENTION 
     Printing machines normally include a printing couple which comprises a number of cylinders and/or rollers such as impression cylinders, master cylinders, blanket cylinders, ductor rollers, transfer rollers, oscillating rollers, form rollers, and the like. For instance, a printing head may be provided generally at the top of the machine, often at the rear of the machine, and which includes an ink fountain for feeding ink to the various rollers of the printing couple which transfers images to copy sheets. A number of rollers which generally can be termed “distribution” rollers are provided between the ink fountain and the printing couple for distributing ink to the printing couple. The distribution rollers conventionally are mounted between spaced side frame plates of the machine framework. 
     One of the problems with printing machines of the character described above is the continuing time consuming, inefficient and “messy” processes or systems for feeding or adding printing ink to the ink fountain. 
     This is particularly problematic with offset or “four color” printing processes wherein different colors of ink must be changed for any single printing run. 
     Printing ink is manufactured and supplied in typical cans very similar to ordinary cans of paint, but with a different type of lid. The ink cans are cylindrical, with a closed bottom end and fairly conventional dimensions. It is not uncommon for ink to be fed to the ink fountain of a printing machine simply by manually pouring the ink from the can. Printing ink is very thick or viscous, and such manual processes are time consuming, inaccurate and often a messy or sloppy job. Rarely are the full contents of an ink can poured into the ink fountain. Mechanized ink feeding apparatus have been used, but such apparatus most often are for large printing machines and are very elaborate and expensive. 
     The present invention is directed to solving these problems and providing a very simple, inexpensive and efficient apparatus, system or method of feeding or supplying ink to a printing couple of a printing machines 
     SUMMARY OF THE INVENTION 
     An object, therefore, of the invention is to provide a new and improved feeding system or method of supplying ink to an ink fountain of a printing, duplicating or like machine. 
     In the exemplary embodiment of the invention, the system includes a can holder for holding a conventional can of printing ink. A support suspends the can holder and can above the ink fountain. Feeding means are provided for feeding ink from the suspended can into the ink fountain. 
     As disclosed herein, the support includes an articulated arm for suspending the can at different positions above the ink fountain. The can holder comprises a housing on a distal end of the articulated arm. The housing has an interior cavity sized complementary to the conventional can, along with a door for closing the cavity. Normally open switch means are provided on the housing and operatively associated with the feeding means, the switch means being closable by the door in a closed position. Additional normally open switch means may be provided on the housing and closable by the can positioned within the cavity in the housing. 
     The feeding means comprises a piston-and-cylinder device for forcing ink from the can into the ink fountain. A disposable gasket is fitted into the can and is engageable by a piston head of the piston-and-cylinder device. A sensor may be provided at the ink fountain operatively associated with the feeding means for feeding ink in response to sensing a given level of ink in the ink fountain. 
     The invention contemplates a method which includes the steps of forming a hole in the closed end of the ink can. The lid is removed from the opposite end of the can, and a gasket is positioned into the can onto the surface of the ink. The feeding means, such as the piston-and-cylinder device, then applies pressure to the gasket to force ink from the can through the hole in the can and into the ink fountain. The gasket is an inexpensive, readily disposable component of the system and protects the feeding means, such as the piston of the piston-and-cylinder device, from coming into any direct contact with the ink in the can. 
     Other objects, features and advantages of the invention will be apparent from the following detailed description taken in connection with the accompanying drawings. 
    
    
     BRIEF OF THE DRAWINGS 
     The features of this invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with its objects and the advantages thereof, may be best understood by reference to the following description taken in conjunction with the accompanying drawings, in which like reference numerals identify like elements in the figures and in which: 
     FIG. 1 is a perspective view of the ink feeding system of the invention, mounted generally above an ink fountain of a printing head; 
     FIG. 2 is a view similar to that of FIG. 1, with the can holder moved to a position directly above the ink fountain and showing ink being dispensed into the fountain; 
     FIG. 3 is a top perspective view of a conventional can of printing ink; 
     FIG. 4 is a bottom perspective view of the can, and showing a hole being formed in the bottom closed end of the can; 
     FIG. 5 is a perspective view of the can, with the lid removed and in conjunction with a stack of disposable gaskets according to the invention; 
     FIG. 6 is a perspective view showing one of the gaskets positioned on top of the surface of the ink in the can; 
     FIG. 7 is a perspective view of the can holder, showing the door of the housing open for receiving a can of ink; 
     FIG. 8 is a fragmented perspective view somewhat similar to that of FIG. 7, showing a can of ink positioned in the housing; and 
     FIG. 9 is a view similar to that of FIG. 8, with the door of the housing closed. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to the drawings in greater detail, and first to FIG. 1, the invention is embodied in an ink feeding apparatus or system, generally designated  10 , mounted on a platform  12  projecting outwardly from a side frame plate  14  of a printing head, generally designated  16 . The printing head is part of a printing couple of a printing, duplicating or like machine and includes an ink fountain  18  defined between an inclined wall  20  of the framework and an ink roller  22 . The printing head includes a number of rollers  24  which generally can be termed “distribution” rollers for providing ink from ink fountain  18  to the printing couple of the machine. The distribution rollers are mounted between side frame plates  14  of the machine framework. 
     Ink feeding system  10  generally includes an ink can holder, generally designated  26 , mounted on the distal end of an articulated support arm, generally designated  28 . The articulated support arm includes a pair of arm portions  30  and  32 . Arm portion  30  is mounted by a swivel bracket  34  to platform  12 , whereby arm portion  32  can pivot in a vertical direction as indicated by arrow “A” as well as swivel in a horizontal direction as indicated by arrow “B”. Arm portions  30  and  32  are interconnected by a pivot bracket  36 , whereby the arm portions are pivotable relative to each other in the direction of arrow “C”. Can holder  26  is connected by a pivot bracket  38  to the distal end of arm portion  32  so that the can holder can be maintained in a horizontal disposition. 
     While FIG. 1 shows can holder  26  positioned horizontally away from ink fountain  18 , FIG. 2 shows articulated support arm  28  having moved the can holder in the direction of arrow “D” to a position immediately above ink fountain  18  whereat ink can be deposited into the fountain, as at  40 . The articulated support arm allows for the can holder to be positioned anywhere along the length of the ink fountain as well as to be moved horizontally completely away from the printing head to allow for cleaning, service or the like. 
     FIGS. 3 and 4 show a conventional ink can, generally designated  42 , for holding a supply of ink. The can is typical and includes a cylindrical side wall  44 , a closed bottom wall  46  and a removable lid  48 . The can is on the order of 6¾ inches high and 6⅞ inches in diameter. As will be described in greater detail hereinafter, the system and method of the invention contemplates forming a hole  50  in bottom wall  46  by means of a punch, drill or like tool  52 . 
     FIG. 5 shows ink can  42  with lid  48  removed to expose the top surface of a supply of ink  54  in the can. A plurality of disk-like gaskets  56 , according to the invention, are shown stacked alongside the open can. The gaskets are slightly smaller in diameter than cylindrical wall  44  of the can, and FIG. 6 shows one of the gaskets positioned on top of the ink  54  in the can. The gaskets are made of such material as coarse rubber and are designed to be readily disposable. 
     FIG. 7 shows can holder  26  to comprise a housing at one side of a control box  58  and defining a cylindrical interior cavity  60  sized complementary to the configuration of one of the ink cans  42 . A semi-cylindrical door  62  is hinged at  64  for closing and opening cavity  16  in the direction of double-headed arrow “E”. The free edge of the door has a radially outwardly extending flange  66 . The housing has a circular bottom wall  68  provided with an opening  70  which will be in alignment with hole  50  (FIG. 4) in the closed end  46  of ink can  42  when the can is fully positioned in the can holder. 
     Generally, feeding means are provided for feeding ink  54  from can  42  suspended in can holder  26  above ink fountain  18 . More particularly, a piston-and-cylinder device, generally designated  72  (FIGS.  2  and  7 ), projects upwardly from a top wall  74  of can holder  26 . The device includes a piston  76  reciprocal within a cylinder  78  in the direction of double-headed arrow “F” (FIG.  7 ). A conduit  80  leads from the cylinder to an appropriate pneumatic source (not shown). Piston  76  extends through top wall  74  of can holder  26  and has an enlarged disk-like piston head  82  secured thereto at the underside of top wall  74  within interior cavity  60 . 
     FIG. 8 shows one of the conventional ink cans  42  positioned within interior cavity  60  of can holder  26  on bottom wall  68  thereof. When so positioned, hole  50  (FIG. 4) in closed end  46  of the can will be in alignment with opening  70  (FIG. 7) in bottom wall  68  of the can holder. Piston head  82  is smaller in diameter than the open end of the ink can for engaging gasket  56  (FIG. 6) which was placed on the top surface of the ink in the can. When piston-and-cylinder device  72  is actuated, piston  76  moves downwardly within cylinder  78  in the direction of arrow “G” to drive piston head  82  against gasket  56  to force ink from the can through hole  50  (FIG. 4) and into ink fountain  18 , as at  40  in FIG.  2 . The gasket scrapes the inside walls of the can and prevents the ink from getting all over the piston head as well as the interior of can holder  56 . The viscosity of the ink prevents the ink from flowing out of hole  50  in the closed end of the can. In other words, the hole should be big enough to allow the ink to be forced there-through, but not so big as to allow the ink to freely flow through the hole. 
     Generally, a normally open switch means is provided on the can holder or housing and operatively associated with piston-and-cylinder device  72  to prevent operation of the device unless door  62  is closed. More particularly, FIGS. 7-9 show a pair of switch contacts  84  which are engageable by flange  46  of the door. Either the door and flange can be conductive to close the contacts, or the contacts can comprise redundant switch buttons which will close a circuit to the piston-and-cylinder device only when the door is closed in the direction of arrow “H” (FIG.  9 ). 
     Another normally open switch means is provided on can holder or housing  26  and is operatively associated with the piston-and-cylinder device to prevent the device from operating unless a can  42  is fully positioned in the can holder. More particularly, FIG. 7 shows a switch  86  which are engageable by can  42  which typically is fabricated of conductive metal material. 
     Finally, FIGS. 1 and 2 show an electronic assembly  88  which has an ultrasonic sensor to sense the level of ink in fountain  18 , along with an aiming light which performs a dual function of aligning the ink dispensing and also aligning the level sensor. The sensor is electrically coupled to piston-and-cylinder device  72  to actuate and deactuate the device in response to the sensing of predetermined levels of ink in the ink fountain. The electrical lines between the controls for the piston-and-cylinder device and the sensor, as well as between switch contacts  84  and  86 , are not shown in the drawings in order to avoid cluttering the depiction of the invention. Obviously, one of ordinary skill in the art could readily interconnect the sensor and switch contacts to the controls of the piston-and-cylinder device. 
     It will be understood that the invention may be embodied in other specific forms without departing from the spirit or central characteristics thereof. The present examples and embodiments, therefore, are to be considered in all respects as illustrative and not restrictive, and the invention is not to be limited to the details given herein.