APPARATUS AND METHOD FOR DECORATING CANS Field of the Invention This invention relates generally to can decorating apparatus of the type used to print wet ink images on the outer surface of a one-piece aluminum or steel can body member of a two-piece can assembly and more particularly to the ductor roll which is used to transfer ink from a fountain roll to a distributor roll. Background of the Invention A can decorating apparatus is described and illustrated in U.S. Patent No. 4,741,266 to Stirbis et al. , the disclosure of which is incorporated herein by reference. As illustrated in Fig. 1 of the Stirbis et al. patent, there are a plurality of circumferentially spaced ink transfer roll and fountain stations for supplying wet ink to separate individual blanket segment means through an equal number of plate cylinder means at six separate inking stations during rotation of the blanket means. At each of the inking stations, a ductor roll is used to transfer ink from a fountain roll to a distributor roll. The ductor roll in the Stirbis et al. patent is pivotally mounted and is spring urged against a rotating cam which cam is driven by the central drive means operating the can decorating apparatus. As the cam rotates, it moves the ductor roll into contact with the fountain roll or the distributor roll. Thus, the amount of time that the ductor roll is in contact with either the fountain roll or the distributor roll depends

on the operating speed of the can decorating apparatus. This amount of time can be varied by use of adjustable cams but creates down time for the can decorating apparatus and are of limited use. Brief Description of the Invention

This invention provides actuating means for moving at least one ductor roll into or out of contact with a fountain roll or a distributor roll that is independent and separate from the main driving system of a can decorating apparatus.

In a preferred embodiment of the invention, each inking station of a can decorating apparatus is provided with a support frame which is part of the main support structure for the can decorating apparatus. A fountain roll having a generally cylindrical outer peripheral surface is mounted for rotation on the support frame so that a portion thereof moves through a supply of ink contained in a pan supported on the support frame. The fountain roll rotates about a generally horizontal axis and is driven by conventional drive means as illustrated in the Stirbis et al. patent. Conventional doctor blade means are provided for removing excess ink from the generally cylindrical outer peripheral surface of the fountain roll. A distributor roll having a generally cylindrical outer peripheral surface is also mounted for rotation on the support frame. The distributor roll rotates about an axis that is substantially parallel to the axis of rotation of the fountain roll and is located so that the peripheral outer surfaces of the fountain roll and distributor roll are spaced apart. The distributor roll is rotated by the conventional drive means described above. At least one ductor roll having a generally cylindrical outer peripheral surface is mounted for rotation about an axis that is substantially parallel with the axes of rotation of the fountain roll and the distributor roll. Pivot means are provided for pivotally mounting the at least

one ductor roll to move its generally cylindrical outer peripheral surface into a contacting relationship with the generally cylindrical outer peripheral surface of either the fountain roll or the distributor roll to transfer at least a portion of the wet ink from the fountain roll to the distributor roll. Actuating means are provided for moving the pivot means to move the at least one ductor roll into either of the contacting relationships. Variable control means are provided for controlling the movement of the actuating means so as to maintain the contacting relationship of the at least one ductor roll with either of the fountain roll or the distributor roll for any desired amount of time to control the quantity of wet ink transferred from the fountain roll to the distributor roll. The variable control means are independent and separate from the main driving means. In the preferred embodiment of the invention, the at least one ductor roll comprises five pivotally mounted and individually controlled ductor rolls having a combined axial extent of their generally cylindrical outer peripheral surfaces which is substantially equal to the axial extent of the generally cylindrical outer peripheral surface of either the fountain roll or the distributor roll which have substantially the same axial extent.

Brief Description of the Drawings An illustrative and presently preferred embodiment of the invention is shown in the accompanying drawings in which: Fig. 1 is a can decorating apparatus of the

Stirbis et al. patent;

Fig. 2 is a top plan view of the can decorating apparatus of Fig. 1,

Fig. 3 is a perspective view of a schematic illustration of the preferred embodiment of this invention;

Fig. 4 is a side elevational view of Fig. 3;

and

Fig. 5 is a schematic illustration of valve means for this invention.

Detailed Description of the Invention In general. Fig. 1 shows a decorator apparatus comprising a mandrel wheel means 30 for receiving undecorated can body members 32 from an infeed means 34. Can body member 32 are supported on a plurality of equally circumferential spaced mandrel means 36 for movement with the mandrel wheel means past a blanket wheel means 38 which carries a plurality of circumferentially spaced blanket segment means 40 having ink and inked images thereon. Each blanket segment means 40 engages the cylindrical outer peripheral surface of a can body member 32 to apply variable color ink and ink images thereon in the form of a label including a brand name, printed matter, decorative images, etc. An overvarnish means 41 may be provided to apply an overvarnish coating material to the inked can members. Decorated can body members 42 are carried to a transfer wheel means 44 and transferred from the mandrels 36 to carrying devices 46 such as suction cup support members. Decorated can members are carried on transfer wheel means 44 to a pin-chain means 47 driven by a sprocket wheel means 48 and having pin members 49, which receive the decorated can members from the transfer wheel means 44. An electric motor-type drive means 50 is connected by suitable transmission apparatus to provide a main drive system to each of the driven devices. Fig. 2 including belt means 51, gear box means 52, belt means 53, a main shaft 54, gear box means 55 for driving the mandrel wheel and the transfer wheel, belt driven gear box means 55A for driving the over¬ varnish means 41, shaft and coupling means 56, belt and pulley means 56A, gear box means 57 for driving the blanket wheel and associated plate cylinders 70, shaft and coupling means 58, gear box means 59 and belt-pulley

means 60 for driving the inker station roll systems, all of which are synchronously driven for the intended purposes. A main base frame means 61 and vertical support devices 61A, 61B, etc. support the afore- described apparatus in a conventional manner. The blanket wheel means 38 and ink station apparatus are supported by a vertically extending rigid plate frame means 62 as shown in Fig. 1 and are located in a housing means comprising a rear plate means 62A and side panels 62B. A plurality of circumferentially-spaced ink transfer roll and fountain means 63, 64, 65, 66, 67, 68 are mounted on frame plate means 62 for supplying ink to the separate individual blanket segment means 40 through an equal number of plate cylinder means 70 at six separate inking stations during rotation of the blanket wheel means 38.

The ink fountain and transfer system of this invention is illustrated in Figs. 3 and 4. A support frame 102 is fixedly mounted on the rigid plate frame means 62. A shaft 104 is mounted on the support frame 102 for rotation in bearing means 106 mounted on the support frame 102 and is rotated by the belt-pulley means 60 by suitable connecting means (not shown) . An engraved fountain roll 108 is secured to the shaft 104 for rotation therewith and has a generally cylindrical outer peripheral surface 110 which passes through a wet ink supply 112 contained in a pan 114 as the fountain roll 108 is rotated. The fountain roll 108 rotates in the direction indicated by the arrow 116 and conventional doctor blade means 118 are provided for removing excess wet ink from the generally cylindrical outer peripheral surface 110. The fountain roll 108 rotates about an axis 120 that lies generally in a horizontal plane. A distributor roll 130, Fig. 4, having a generally cylindrical outer peripheral surface 132 is secured to a shaft 134 for rotation therewith which

shaft 134 is rotatably mounted on conventional support means (not shown) mounted on the rigid plate frame means 62 and rotated by the belt pulley means 60. The distributor roll 130 rotates about an axis 136 that is substantially parallel with the axis of rotation 120 and rotates to have a surface speed of about twenty times that of the fountain roll. The distributor roll 130 is mounted so that the generally cylindrical outer peripheral surface 132 thereof is spaced from the generally cylindrical outer peripheral surface 110 of the fountain roll 108.

The wet ink transferring system of this invention for transferring wet ink from the fountain roll 108 to the distributor roll 130 is illustrated in Figs. 3 and 4 and comprises five movably mounted ductor rolls 140. Although five movably mounted ductor rolls 140 are illustrated and described herein, it is understood that the wet ink transferring system may comprise at least one ductor roll 140 or any number of a plurality of ductor rolls 140 other than the five ductor rolls 140. Each ductor roll 140 is mounted on its own shaft 142 so as to be freely rotatable relative thereto and which shaft 142 is secured in one end portion 144 of a rotatable lever arm 146. A shaft 148 having reduced end portions 150 is fixedly mounted on the support frame 102 by locating the reduced end portions 150 in mounting blocks 152 which are secured to the support frame 102 by headed threaded bolts 154. Each lever arm 146 is rotatably mounted on a shaft 148 for rotation relative thereto about an axis 156 that is substantially parallel to the axes of rotation 120 and 136. The other end portion 158 of the lever arm 146 is rotatably mounted on a pin 160 which is fixedly secured in a bifurcated end portion 162 of a piston rod 164, each of which functions as actuating means to move a lever arm 146. Each piston rod 164 is mounted for linear sliding movement on a piston 165 which is slidably mounted in an air cylinder

166 which has a lower support member 168 which is rotatably mounted on a pin 170 which is fixedly secured in a bifurcated portion 172 of a mounting block 174. Each mounting block 174 is fixedly secured to the support frame 102 by headed threaded bolts 176. Each ductor roll 140 is mounted for rotation about an axis 178 that is substantially parallel with the axes of rotation 120, 136 and 156. Each ductor roll 140 has a generally cylindrical outer peripheral surface 180 which is moved by a piston rod 164 into a contacting relationship with either the generally cylindrical outer peripheral surface 110 or 132 of the fountain roll 108 or the distributor roll 130 or not in contact with either. As illustrated in Fig. 4, the movement of each ductor roll 140 is through a very small distance such as between about 1/16 and 3/16 of an inch.

Variable control means 186 are provided for controlling the movement of each piston rod 164 so as to maintain the contacting relationship of each ductor roll 140 with the fountain roll 108 or the distributor roll 130 for any amount of time to control the quantity of wet ink transferred from the fountain roll 108 to the distributor roll 130. The variable control means 186 have a plurality of control knobs 188 each of which functions through an air cylinder 166 to control the movement of a piston rod 164. A plurality of movable valve means 190, Fig. 5, are mounted in the variable control means 186 and each valve means 190 has an inlet tube 192 that is connected by means (not shown) to a main inlet tube 194, Fig. 3, which supplies air under pressure from a pressurized air source (not shown) . Each valve means 190 has a solenoid actuated valve 196 that directs a flow of pressurized air into either a flexible tube 198 extending between a valve means 190 in the variable control means 186 and the bottom 200 of each air cylinder 166 to move the piston rod 164 in an outward direction or a flexible tube 202 extending

between a valve means 190 in the variable control means 186 and the top 204 of each air cylinder 166 to move the piston rod 164 in an inward direction. The solenoid actuated valve 196 is normally in a position whereat the ductor roll 140 is in contact with the distributor roll 130. Each of the control knobs 188 is multi-purpose signal generating unit which sends appropriate signals through electronic conducting cables 206 to a micro¬ processor (not shown) to control the movement of the ductor rolls 140 in response to a program controlling the operation of the can decorating apparatus illustrated in Fig. 1. The variable control means 186 permit operation of the ductor roll 140 independent and separate from the electronic motor type drive means 50. It is understood that other types of control means may be used instead of the illustrated variable control means and the air cylinders so long as they are designed to move and hold the ductor rolls in contact with the fountain roll and distributor roll for the desired sequence of operations.

The operation of the wet ink transferring system of this invention is explained in relation to Fig. 3 wherein each of the ductor rolls 140 have been identified by one of the letters A through E. The number of ductor rolls 140 used to transfer wet ink from a fountain roll 108 to a distributor roll 130 at each of the ink transfer and fountain means 63, 64, 65, 66, 67 and 68 may be varied as desired. For example, at ink station 63, the variable control means 186 may be programmed to move ductor rolls A, B and E at desired intervals into contact with the fountain roll 108 for a period of time and then back into contact with the distributor roll 130 for a period of time to transfer the desired amount of the wet ink, while at ink station 64, the variable control means 186 may be programmed to move ductor rolls B, D and E at desired intervals into contact with fountain roll 108 for a period of time and

then back into contact with the distributor roll 130 for a period of time to transfer the desired amount of wet ink. Thus, each of the ink stations 63 - 68 may be programmed to use as many of the ductor rolls A - E as desired to transfer wet ink from the fountain roll 108 to the distributor roll 130. The amount of wet ink transferred depends on how many times a ductor roll 140 is moved into contact with the fountain roll 108 and how long such contact is maintained. While an illustrative and presently preferred embodiment of the invention has been described in detail herein, it is to be understood that the inventive concepts may be otherwise variously embodied and employed and that the appended claims are intended to be construed to include such variations except insofar as limited by the prior art.