US3180257A - Printing unit - Google Patents

Description

A. F. SHIELDS PRINTING UNIT April 27, 1965A 4 Sheets-Sheet 1 Filed Nov. 6v, 1962 .www

4 Sheets-Sheet 2 IN VEN TOR. 065er f, .JW/zas A. F. SHIELDS PRINTING UNIT April 27, 1965 Filed Nov. 6. '1962 lh' l" H April 27, 1965 A. F. sHllv-:LDs 3,180,257

PRINTING UNIT Filed Nov. e, 1962 4 shets-sneet s INVEN TOR. Wafer H ffy/e205 April 27; `A1,965 A. F. sHlELns 3,180,257

PRINTING UNIT Y Filed NQv. e,v 1962 4 sheets-sheet 4 IN VEN TOR. Azaer .IW/zas United States Patent() arsazs' PRINTING UNIT Albert ll?. Shields, 43 Exeter St., Forest Hills, NKY. Filed Nov. 6, 1962, Ser. No. 235,658 1 Claim. (Cl. lill-154) This invention relates to printing units in general and more particularly to units of this type designated as sheeting presses.

In general, printing units for the paper board box industry are requiredto print on individual sheets of material as distinguished from material in the forni of a continuous web. This type of printing unit is usually located in close proximity to a device which slits, slots and scores blanks. Because of this the region in which the printing unit is located is relatively dusty. Quite Often dust particles come to rest upon the fountain cylindex' which transfers ink from the ink pan to the printing cylinder. In prior art devices these particles interfere with the transfer of ink to the priming cylinder and in turn interfere with the quality of printing.

Accordingly, it is a primary object of this invention to provide a printing unit constructed in such a manner that a high quality of printing will be maintained even when operation of the printing unit takes place in a relatively dusty atmosphere. This is accomplished by providing a doctoring means for the fountain roll in the form of a scraper blade rather than a wiper blade. That is, in the instant invention the blade is disposed at an obtuse angle with respect to the fountain cylinder surface which is moving toward the blade. This isrin contrast to prior art devices in which the corresponding angle is acute. When the angle is acute a wedge-shaped area is formed, between the blade and fountain cylinder, whichacts to trap dusty and foreign particles. When there is asufcient accumulation of these lforeign particles the blade is prevented from properly performing its doctoring function so that either too much or too little ink will be transferred to the printing cylinder.

ln the device of the instant invention the scraper blade is mounted in such a manner that fluid pressure means disposed along the length of the blade urges the blade against the periphery of the fountain cylinder. Further, means are provided to oscillare the blade parallel to its longitudinal axis to further insure that foreign particles will not lodge along the line of contact between the blade and fountain cylinder. The mounting for the blade and fluid pressure means is such that the blade may readily be moved to a position which is convenient for inspection and/or eventual replacement. The ink dellecting apron is mounted so as to be movable as a unit Vwith the blade when the latter is to be inspected so that this movement may be accomplished without moving the fountain cylinder.

In the paper box'industry printing often takes place in relatively short runs and it is necessary to change ink colors for each run. Because of this the device of the instant invention provide-s a relatively shallow ink pan and means whereby one pan may be readily removed and replaced by a second pan having a diflerent color ink. This is accomplished by providing atrack means including a movable portion which is pivoted into position. The movable track portion supports the pan during the printing operation and during the changing operation the pan is supported by a stationary portion of the track means.

In the device of the instant invention the printing cylinder is disposed between the fountain cylinder and pressure cylinder. In prior art devices of this type `when the printing cylinder was stopped the pressure cylinder Vwould continue to force the blank against the printing of bracket 36.

3,189,257 Patented Apr. Z7, 165

die. Under these conditions, if a printing cylinder was stopped for a time interval of appreciable length the blank would stick to the printing die.

This condition will not arise with the device of the instant invention since it is provided with means for automatically moving the pressure cylinder away from the printing cylinder when the printing cylinder is stopped. Thus, pressure on the blank is relaxed.

Accordingly, another primary object of this invention is to provide a novel construction for a printing unit.

` Another object is to provide a printing unit which is more reliable than similar units of the prior art.

Still another object is to provide a printing unit having novel provisions whereby one ink pan may be removed and replaced by a different ink pan.

A further object is to provide a printing unit having a novel scraper blade for controlling ink transfer to the printing cylinder.

These as well as other objects of this invention shall become readily apparent after reading the following description of the accompanying drawings in which:

FIGURE 1 is a perspective of the fountain cylinder and portions of the doctoring means assembly looking at the rear of the machine. Y

FGURE 2 is a fragmentary side elevation, partially sectioned, of a printing device constructed in accordance with the teachings of the instant invention. i

EEGURE 3 is a plan view of the portion of the unit illustrated in FGURE l with many details added.

FlGURE 4 is a side elevation in somewhat schematic form of a machine constructed in accordance with the teachings of the instant invention.

ElGURE 5 is an enlarged fragmentary view showing the scraper blade in engagement with the fountain cylinder. Now referring to the figures and more particularly to FlGURE 4. Printing apparatus 19 comprises fountain cylinder 11, printing cylinder 12 and pressure cylinder 13 mounted one above the other and extending between stationary frame sections 15. The axes 21, 22, 23 for cylinders 11, 12, 13, respectively, are horizontally disposed. Disposed below fountain roll 11, is ink pan 16A and disposed on the output side of fountain cylinder 11 is a doctoring assembly Ztl.

With apparatus 1d operating, that is, with cylinders 11 through 13 rotating, the periphery of fountain roll 11 extends below the ink level in pan 1e thereby picking up a layer of ink. The external surface of cylinder 11 rs roughened as by etching or embossing so as to facilitate inkretention. This ink layer is doctored by scraper blade 25. of assembly 2@ to the proper thickness for transfer to printing mat 19 secured to the periphery of printing cylinder 12.

Printing cylinder 12 is rotated in the direction indicated by arrow B (FIGURES 2 and 4) and blanks (not shown) are moved in the direction of arrow A (FIGURE 4) between cylinders 12 and 13 where pressure is applied to the blank whenthe ink coated mat 19 engages the blank. As will'be hereinafter seen the force exerted by pressure cylinder 13 is adjusted by means of assembly 26 to insure that the proper pressure is applied to the blank as it passes over mat 19.

Particular reference is now made to FIGURES 1 through 3 for details of doctoring means 2t). Scraper blade 2S is an extremely thin elongated member clamped between elongated plates 31 and 31a by fastening means 32 (FIGURE 5). The ends of plate 31a are secured to hinge means 34- (FIGURE 2). Fasteners 35 secure one leg of each hinge means 34 to one leg of elongated bracket 36 with blade 25 being disposed opposite the Aother leg In FGURE 2 fasteners 37 secure the first mentioned 3 leg of bracket 36 to legs 41 of short brackets 42 while the other legs 43 of short brackets 42 are secured to transverse member 45 by fasteners 46. As clearly seen in FIGURE 1 there are a plurality of brackets 42 secured to a single transverse member 45.

Bar 45 is of rectangular cross-section turned round at both ends to form shaft extensions 48 about which bar 45 is pivotable relative to frame uprights 15. A bracket 49 is mounted at each end of bar 45 inboard of uprights 15. Each upright supports a pivot unit 47 having a roller 72 enterable into slot 73 of bracket 49 for a reason to be hereinafter explained and when so disposed maintain blade 25 in contact with fountain roll 11. By rotating bar 45 doctoring means 20 is movable from the working position of FIGURE 2 in a clockwise direction away from fountain roll 11 to a position for inspection wherein bar 45 rests against support 89. In this position blade 25 and the other elements of means 2l) are accessible for inspection and replacement.

Each bracket 49 carries elongated tubular member 5t) extending parallel to member 45. A plurality of longitudinally spaced air cylinders 51 are mounted internally of tubular member 50 with a piston extension 52 extending from each cylinder 51 externally of tubular member 50. The free ends of piston 52 engage support plate 31a so that when extensions 52 are urged outward blade 25 is urged into engagement with the periphery of fountain cylinder 11. Air pressure for the actuation of cylinders 51 is supplied through main conduit 54 and individual pipes 55. Main conduit 54 extends through spacer plates 56 mounted to tubular member 50.

Apron 59 extends downwardly from support plate 31a into ink pan 16 to a point below the ink line. Apron 59 is so positioned that excess ink will not splatter but will be deflected so as to take the path indicated by arrows C (FIGURE 2).

With assembly in the operation position of FIG- URES 1 and 2 followers 72 are in grooves 73. Fluid under pressure is supplied to cylinders 51 of FIGURE 2 so that piston extensions 52 are moved outwardly thereby urging scraper blade into engagement with fountain roll 11. Blade 25 is pivoted at hinge 34 so that the former is free to engage roll 11 with a pressure controlled by the fluid pressure in conduit 54. It is noted that by providing a plurality of cylinders 51 distributed along the length of blade 25 the pressure of blade 25 against cylinder 11 is evenly distributed. g

It is also noted that blade 25 is disposed at an obtuse angle with respect to the surface of cylinder 11 moving toward the edge of blade 25. Stated in a different manner, there is an obtuse angle formed between blade 25 and the tangent extending from the line of contact between blade 25 and cylinder 11 in the direction opposite to the direction in which cylinder 11 is rotated. This has the advantage of eliminating areas between the blade and cylinder 11 where particles of dirt may lodge.

Assembly 20 is vibrated longitudinally by an eccentric means 63a. Worm 62 and gear 63 drives eccentric means 63a in the form of a crank with a roller disposed within a vertical slot of block 64 ailixed to shaft 48 in a manner to cause axial movement of shaft 48 but permit shaft 48 to pivot relative to block 64. This movement is of block 64 restrained to an axial direction by roller 65 secured to frame bracket 66 which is disposed within slot 67 of the housing for means 64. This longitudinal vibrating motion is also restrained to an axial direction by locking assemblies 68. Each of the assemblies 68 includes a member 69 pivotally mounted to member 47 for rotation about shaft 70. Handle 71 extends radially from shaft 70 for accomplishing this pivotal movement. The end of member 69 remote from shaft 70 is provided with roller 72 which is disposed within open ended slot 73 of member 49. FIGURE 1 shows a locking means in locking position. The left locking means is moved to unlocking position by moving handle 71 in a counterclock- 4 wise direction with respect to FIGURE l while the right hand locking means 61 is moved to unlocking position by pulling this handle 71 in a clockwise direction. These movements removed the respective rollers 72 from slots 73.

With both locking means 68 in their unlocking positions handle 76 mounted to shaft extension 48a may be operated to pivot assembly 20 clockwise with respect to FIGURE 2 to a position wherein members 42 rest upon cushion layer 79 of support means 80. Assembly 20 is then in a convenient position for repair or replacement of any of the elements thereof. It is noted that apron 59 is so mounted and constructed that this pivotal movement of assembly 2t) may take place without the necessity of moving ink cylinder 11 out of position.

It is noted that ink pan 16 (FIGURE 2) is very shallow and that the ink level therein is very low. This is done purposely so that, especially in short runs, an excessive amount of ink will not be required. It is noted that iloat means (not shown) are utilized for control of a valve which in turn controls the flow of ink from a reservoir into pan 16. Extending outboard from pan 16 at the ends thereof are rollers 81 and 82. In the operating position of yFIGURE. 2 roller 81 is disposed within depression S3 at the free end of movable track section 85. The other end of track sections 85 is pivoted to frame 15 at stub shaft 84. Track 65 is moved in a clockwise direction with respect to FIGURE 2 about pivot 84 to raised position, by means of crank 86. Crank 86 is pivoted to frame 15 at stub shaft 87 and is provided at its free end with roller 88.

Crank 87 is movable from the dotted line position of FIGURE 2, resting against stop S9, to the solid line position. During this movement roller 88, in engagement with the lower surface of track S5, causes track 85 to pivot clockwise about its pivot 84. This movement ceases when roller 8S abuts stop surface 91 on the underside of track 85. It is noted that surface 91 is positioned to the left of the vertical passing through crank pivot 87 so that the downward forces now acting upon roller 88 urge crank 86 in a counterclockwise direction.

In order to lower pan 16 it is necessary to remove wing nuts 92 mounted to studs 93 which extend forward of pan 16 and secure pan 16 to front splash shield 94. Crank 86 is then operated in a clockwise direction until it rests upon stop 89. During this movement of crank S6, movable track section 85 pivots counterclockwise and lowers pan 16 until front roller 81 rests upon stationary track section 95. Roller 81 is initially positioned to the right of high point 96. Since roller 82 at this time rests upon the downwardly sloping upper surface of movable track 85 roller 81 rests against stationary track surface 97.

Roller 81 is then lifted over high point 96 and on to the forwardly sloping Section 98 of stationary track 95. Pan 16 is then drawn forward until roller 81 engages surface 99. Pan 16 may then be lifted and bodily removed for cleaning and another pan placed upon stationary track section 95. This other pan is then moved into operating position by first moving it rearward on stationary track 95 until its front roller passes over high point 96. Thereafter crank 86 is operated in a counterclockwise direction. As movable track S5 pivots clockwise depression S3 receives the forward roller and continued movement of movable track 85 is effective to raise pan 16 into operating position. It is noted that' when pan 16 is supported by stationary track 95 with the forward roller resting against surface 99, the pan 16 is in a convenient position to be emptied and cleaned. It is also nOted that there are individual movable and stationary track sections 85 and 95 at each side of frame 15.

During the periods when printing roll 12 is stopped it is necessary to maintain fountain cylinder 11 rotating with its outer surface passing through the ink bath. If this were not done, the ink on the outer surface of cylinder 11 being of a fast drying type, would rapidly harden and form an unwanted layer which would be dicult to remove. Thus, air cylinder 100 is provided. Cylinder' 100 is automatically actuated whenever printing cylinder 12 is stopped and upon actuation of cylinder 100, piston extension 101 moves downward. The lower end of extension 101 is pivotally mounted at 102 to crank 103 whose other end is connected to carrier 104. Carrier 104 is pivotally mounted to frame 15 and is eccentric with respect to bearing 105. The latter is concentric with the center of rotation 21 for fountain cylinder 11.

Thus, when printing cylinder 12 ceases to operate piston extension 101 moves downward thereby pivoting carrier 104 in a direction to lower fountain cylinder 11. At the same time an auxiliary motor is operated to continuously rotate fountain cylinder 11. The spacing between the centers of cylinders 11 and 12 during operation of printing cylinder 12 is established through the engagement of crank with stop 103a.

When printing cylinder 12 is stopped it is also desired that pressure cylinder 13 be raised so that it will not continue to force blanks against the surface of printing cylinder 12. This is accomplished by mounting the axis 23 of vcylinder 13 to an intermediate point of carrier 120. One end of carrier 120 is pivoted to frame 15 at stub shaft 121 while the other end is pivotally connected at 122 to the bifurcated lower end of member 124. It is noted that shaft 121 also defines the center of rotation for gear 125 which drives gear 126 mounted to shaft 23. Gear 126 is the direct driving connection for pressure cylinder 13.

Member 124 is provided at its upper end with an internally threaded portion which receives the threaded lower end portion of shaft 131. The upper end of shaft 131 is Thus, this invention provides a novel doctoring means for the fountain cylinder of a printing device. This ink pan may be readily removed or cleaned and further provides an arrangement whereby pressure between the pressure cylinder and printing cylinder is relaxed whenever the printing cylinder is not operating thereby reducing the likelihood that a blank will stick to the printing cylinmounted for rotation in bearing 132 carried by member l 133 which is secured to the lower end of piston rod 131 extending from air cylinder 135. Shaft 131 extends through the housing 136 of adjusting assembly 26. Disposed within housing 136 is worm gear 137 operatively connected to shaft 131 by an elongated key 138 in a manner such that shaft 131 is free to move axially relative to gear 137 yet rotation of gear 137 will be effective to rotate shaft 131. Gear 137 is rotated through the operation of motor driven shaft 139 which drives worm 140 whose teeth are in mesh with the teeth of gear 137.

Air cylinder 135 is a double acting device. That is, it is positively actuated to a raised position and to a lowered position with the lowered position being illustrated in FIGURE 4. The lowered position is the one in which pressure cylinder 13 is maintained While printing cylinder 12 is operating. As soon as printing cylinder 12 ceases to operate, cylinder 135 is actuated to raise piston extension 134. This in turn raises shaft 131 and member 124 to lift pivot point 122 thereby raising the left end of carrier 120. This causes the center of rotation 23 for pressure cylinder 13 to move upwardly so that pressure is no longer applied to printing cylinder roll 12.

Worm 140 is operated to adjust the pressure exerted by cylinder 13 against cylinder 12. That is, when worm 140 is rotated, gear 137 is caused to rotate thereby rotating shaft 131. The lower end of shaft 131 is threaded so that as shaft 131 rotates it moves into or out of the aperture in member 124 depending upon the direction of rotation. This in turn raises or lowers the position of connecting pivot 122, for the position of piston extension 134 illustrated in FIGURE 4, thereby changing the pressure applied by roll cylinder 13 against cylinder 12. It is noted that means (not shown) similar in construction to adjusting assembly 26 are provided to simultaneously adjust stops 103a on opposite sides of the apparatus.

der even though fast drying inks are utilized.

VAlthough there has been described a preferred embodiment of this novel invention, many variations and modilcations will now be apparent to those skilled in the art. Therefore, this invention is to be limited, not by the speciic disclosure herein, but only by the appending claim.

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

A device of the class described comprising a pressure cylinder, a fountain cylinder, a printing cylinder positioned between the other two cylinders with the longitudinal axes of all of said cylinders being substantially parallel and'horizontally positioned, an ink pan below said fountain cylinder, track means upon which said pan is movable between a lirst, a second and a third position, said pan when in said rst position having a portion of said fountain cylinder disposed therein, said pan when in said second and third positions having said fountain cylinder disposed externally thereof, said track means including a movable portion supporting said pan insaid iirst position and a stationary portion supporting said pan in said second and third positions, travel of said pan between said second and third positions being generally horizontal, a pivotal axis for said movable portion, said pivotal axis eX- tending generally parallel to the longitudinal axis of said cylinders, said pivotal am's extending through one end of said movable portion, said other endrof said movable portion being in raised position when said pan is in said lirst position and being in lowered position when said pan is in said second and third positions; said movable portion when in said raised position being above said stationary portion,

' a rst and a second roller means disposed outboard of said pan at opposite ends thereof, said roller means resting solely upon said movable portion when the latter is in said Vraised position, said roller means being engaged by said stationary portion as said movable portion is moved toward said lowered position, said stationary portion having raised formations establishing said second and said third positions, when said pan is in said third position, said rst roller means being disposed remote from engagement by said movable section should the latter be operated to said raised position, when said pan is in said second position both of said roller means being disposed for engagement by saidmovable section as it is operated to said raised position.

Reerences Cited bythe Examiner EUGENE R. CAPOZIO, Primary Examiner. ROBERT E. PULFREY, Examiner.

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