US3178981A - Perforator attachments for offset presses - Google Patents

Description

April 20, 1965 H. E. PAULSON PERFORATOR ATTACHMENTS FOR OFFSET PRESSES Filed Dec. 22, 1958 2 Sheets-Sheet 1 127/6 INVENTOR Ail"! I max mal-m Harv/a L. Pau/s 0/? BY I .annmp ATTORNEY April 20, 1965 H. E. PAULSON 3,178,981

7 PERFORA'I'OR ATTACHMENTS FOR OFFSET PRESSES Filed Dec. 22, 1958 2 Sheets-Sheet 2' E 1 H I I' ll 35 I 6; x @l I Zg l- E 37 Jail- I l I i l a l I l l INVENTOR Hare/o f Pea/Jon ATTORNEY United States Patent '0 3,178,981 PERFORATGR ATTACHMENTS FOR OFFSET PRESSES Harold E. Paulson, 842 W. Nebraska, St. Paul, Minn. Filed Dec. 22, 1958, Ser. No. 782,172 1 Claim. (Cl. 83345) This invention relates to an improvement in perforator attachments for offset presses and deals particularly with an attachment capable of perforating a sheet being carried through an offset printing machine by gripper bars and deals particularly with an apparatus capable of accurately perforating the sheet While the sheet is retained in proper registry.

Considerable difficulty is experienced in perforating paper sheets as they are printed in an offset printing machine. In the past, presses of this type have been provided with low ejector wheels over which the sheets travel at the end of the conveyor carrying the gripper bars and perforating attachments have been applied which are capable of engaging the paper sheets as they pass over these wheels. However, the engagement of the perfrat ing wheels with the sheets usually has a tendency to twist the sheets or flex them sufficiently to cause the perforations to move out of registry. Because of the difficulty experienced in perforating the sheets With such attachments, the attachments have not been particularly popular and under ordinary circumstances the printed sheets are perforated by passing them through a separate perforating machine in an entirely separate operation. 0bviously, this requires passing the sheets through two machines rather than one thus doubling the handling cost. It is an object of the present invention to avoid these previous difficulties and to perforate the sheets at the discharge end of the offset press to eliminate the separate perforating operation.

A feature of the present invention resides in the provision of a perforating attachment which includes a brush extending across the path of travel of the sheets and inclined in the direction of movement of the sheets. This brush engages the surface of each sheet and holds it smoothly against the surface of a roller or plurality of rollers with a light pressure. A perforating means is supported engageable with the sheet just after it has been contacted by the brush. Thus, as the forward edges of the sheets are drawn from the press by the gripper bars, the perforating wheel engages the sheet between the forward edge of the sheet engaged by the gripper bars and the portion of the sheet engaged by the brush. As a result, the perforations extend through portions of the sheets which are under slight tension between the gripper fingers and the brush, and the sheets are maintained in perfect registry during the perforating operation.

A feature of the present invention resides in the provision of an attachment which preferably includes a perforator wheel designed to perforate the paper and a roll down wheel which engages the paper after it has been perforated and tends to flatten down the sheet to prevent a build-up in thickness at the perforated areas.

A further feature of the present invention resides in the provision of a roller over which the sheets travel at the discharge end of the press and which is preferably made in sections. In preferred form, the roller is provided with spaced grooves into which the perforating knives may extend so as to completely perforate the paper. These grooves may also serve as the female portions of a creasing die in the event the sheets are to be creased rather than perforated. While the apparatus is primarily used for perforating operations, it may also be used for creasing purposes by substituting a continuous wheel for the perforating wheel.

A further feature of the present invention resides in Patented Apr. 20, 1965 the provision of a novel means of eliminating static electricity in the sheets being perforated. When sheets become charged with static electricity, they have a tendency to cling to the gripper bars or to the rollers over which the sheets travel and do not discharge properly from the press. It has been found that a strip of tinsel having tiny metallic filaments which engage the surface of the sheet are effective in dissipating the static electricity. Accordingly, I provide a series of angularly spaced supports on certain of the drum or roller segments capable of supporting a strip of tinsel somewhat below the outer periphery of the drum or roll. During rotation of the press, the metallic filaments of the tinsel contact the undersurface of the sheet, preferably at spaced points, and discharge the static electricity so that the sheets will be properly ejected from the press.

An added feature of the present invention resides in the provision of a means of raising the brush above the level of the sheet as the forward end of the sheet engaged by the gripper fingers passes therebeneath. As a result, the brush does not engage the forward edge of the sheet and does not apply tension to the sheet until the forward edge thereof has passed beneath the brush.

A further feature of the present invention resides in the provision of a perforating attachment capable of perforating a line which may be substantially shorter than the length of the sheet. In other words, a perforated line may be produced adjoining either end of the sheet or extending through the intermediate portion of the sheet leaving the ends of the sheet unperforated. This may be accomplished while simultaneously perforating or creasing additional lines extending the full length of the sheet.

A feature of the present invention resides in forming a portion of the drum in sections between which are locked short arcuate sections which are grooved in their peripheral surface. By adding or removing arcuate sections, the angular length of the female die into which the perforating wheel extends may be increased or decreased. In areas where the segments have been removed, the perforating wheel merely bears against the surface of the sheets without perforating the same. In this way, the length and position of the perforated line may be varied.

An added feature of the present invention resides in the provision of a perforating attachment which may, if desired, be used to die out small areas of the paper from the sheets to provide perforated lines. Normal perforations are produced by cutting wheels or cutting rule having sharpened teeth which slit the paper. The wedge shaped edges of the sharpened teeth spread portion of the paper apart and act to increase the thickness of the sheet. By using a perforating wheel with blunt ended teeth, narrow areas of the paper may be punched from the sheet and into a receiving groove in the drum. By this means, the sheet may be perforated without materially increasing the thickness of the sheet along the line of perforation.

A further feature of the present invention resides in the provision of a means of discharging the small punched areas of the sheets which are die cut from the sheets by the blunt the. The groove into which the punched areas are forced is formed between two adjoining disclike segments each provided with angularly spaced apertures communicating with the base of the groove. The apertures of one disc are staggered relative to the apertures of the other thus creating a draft capable of carrying the small particles out of the groove.

These and other objects and novel features of the present invention will be more clearly and fully set forth in the following specification and claim.

In the drawings forming a part of the specification:

FIGURE 1 is an elevational view showing a portion of the delivery end of an offset press showing the perforating device attached thereto.

FIGURE 2 is a cross sectional view through a portion of the press, the position of the section being indicated by the line 22 of FIGURE 1.

FIGURE 3 is a sectional view on a plane parallel to FIGURE 2, the position of the section being indicated by the line 33 of FIGURE 1.

FIGURE 4 is a side elevational view of the support for the perforating wheel and roll down wheel.

FIGURE 5 is an enlarged side view of a segment used in providing skip perforations.

FIGURE 6 is an end view of the segment illustrated in FIGURE 5.

FIGURE 7 is a cross sectional view through an end of the drum forming a part of the perforating attachment.

FIGURE 8 is a sectional view through a portion of the drum illustrated in FIGURE 7, the position of the section being indicated by the line 8-8 of FIGURE 7.

FIGURE 9 is a plan view of the brush portion of the attachment indicating the manner in which the brush is mounted.

FIGURE 10 is a detailed view of a portion of the end of the perforating drum in enlarged form.

The details of construction of the offset press are not illustrated in the drawings in view of the fact that such presses are in common use. The particular press to which the attachment is made in the drawing is known as a Davidson offset press produced by the Davidson Corporation. This press applies an impression on the surface of a cylindrical blanket and transfers the impression to a sheet of paper or the like drawn between the blanket and an adjoining cylinder by gripper fingers mounted upon transverse gripper bars supported by endless conveyor chains. In the operation of the press, the sheets are fed against registering stops and are then fed between feed rollers over the gripper bars. At this point the gripper bars engage the sheet and draw it between the blanket and the adjoining roller. The sheets are then carried by the gripper fingers to the discharge end of the press where the gripper fingers are released permitting the sheets to drop into a suitable sheet catcher. The sheets may be carried around the end of the conveyor to invert the sheet or may be ejected in upright form.

With reference now to FIGURES 1, 2 and 3 of the drawings, the press frame is indicated in general by the numeral 10 and the frame It) acts to support a tranverse shaft 11 bearing spaced sprockets 12 and 13 about which the conveyor chain 14 and 15 extend at the end of the conveyor. Gripper bars such as 16 (FIGURE 2) support gripper fingers 17 which engage the forward edge of the sheet to draw it from its initial registered position to the discharge. The gripping fingers 17 are moved between two p-ositions by suitable cam means not illustrated in the drawings which act to engage and disengage the sheet at the proper points.

The shaft 11 normally supports a series of spaced ejector wheels which carry the sheet to its destination. In the present case, the ejector wheels are removed and are replaced with drum segments or rollers 19 which may be identical in form. One such drum section 19 is illustrated in FIGURE 7 of the drawings and is shown as including one or more hub portions 20 which support ringshaped discs 21 which is connected to the cylindrical drum surface 22. The outer surface of the drum portion 22 is provided with axially spaced grooves 23 for a purpose which will be later set forth in detail.

One or more of the drum sections may act to support a series of angularly spaced projecting studs 24 as illustrated on opposite sides of the center drum section in FIGURE 1 of the drawings. Strips of tinsel 25 are attached to the ends of the studs 24 in any suitable manner, the studs preferably having slots in their ends into which thetinsel'may be forced by friction. The studs 24 support the tinsel sufficiently recessed beneath the surfaces of the drums to prevent the small metal filaments of the tinsel from exerting sufficient force against the sheet to cause distortion of the sheet. At the same time, the tinsel is supported close enough to the surface of the drum to actually contact the sheet as it is drawn over the surfaces of the drum sections.

A shaft 26 is supported by a pair of brackets 27 to extend transversely of the frame in parallel relation to the shaft II. The shaft 26 supports a pair of spaced brackets 22% and 30 in spaced relation on opposite sides of the roller sections 19. As shown in FIGURE 1 of the drawings, the brackets 29 and 30 are substantially similar and include spaced parallel sides 31 and 32 and a connecting base 33 which forms the top of the brackets. brackets 2% and 3t are apertured as indicated at 34 to fit freely upon the shaft 26. A collar 35 is mounted upon the shaft 26 between the spaced sides 31 and 32 of each of the brackets to hold the brackets in proper adjusted position on the shaft 26. The upper base portions 33 of the brackets support bearings 36 which support a transverse connecting shaft 37 so that both of the brackets 29 and 30 move in unison.

As indicated in FIGURE 3 of the drawings, a vertically elongated arm 39 is held to the side 31 of the bracket 29 by a pair of spaced bolts or cap screws 49 which extend through vertically elongated slots 41 in the arm 39. The arm 39 supports near its lower end a transverse pivot 42 which supports a cam follower wheel or hearing 43. A cam 44 is mounted upon the shaft 11 for rotation in unison therewith. This cam 44 is provided with a projecting portion45 which is engageable with the cam roller 43 in one rotative position of the cam. Upon engagement, the cam roller raises the forward end of the bracket 29 which in turn acts through the connecting shaft or tube 37 to lift the second bracket 30.

As indicated in FIGURES 2 and 9 of the drawings, a pair of opposed arms 46 and 47 are adjustably secured to the inner walls 33 of the brackets 29 and 30 by bolts 49 or other suitable means. The ends of the arms 46 and 47 adjustably support a shaft 50 which forms the base of a brush 51 having long bristles capable of extending down into surface contact with the drum sections. The adjustment is controlled by clamping screws 52 which extend through split ends of the arms 46 and 47. The brush 51 is preferably adjusted so it just contacts the surface of the drum sections 19 during the major portion of the cycle of rotation. However, when the arms 46 and 47 on the brackets 29 and 30 are raised upwardly by engagement of the cam roller 43 with the projecting portion 45 of the cam 44, the brush is raised out of contact with the drum. The cam 44 is preferably adjusted so that the brush is lifted as the gripping bars approach and lowered after the gripper bars have passed beneath the brush.

The perforations in the sheets are preferably formed by adjustable perforating wheel supporting units illustrated in general by the numeral 54. The units 54 in preferred form comprise a pair of similar sections 55 and 56 which are hingedly connected together at 57. The opposing walls of the sections 55 and 56 are clamped together by a clamping bolt 59 which projects through ears 60 arranged in opposed relation on the two sections. An aperture 61 extends through the support 54 along the center line between the sections 55 and 56. The aperture 61 is of proer di rnensions so that the two sections may be clamped against opposite sides of the supporting shaft 26.

The sections 55 and 56 each include an aperture therethrough, the apertures being identified by the numerals 62 and 63 respectively. Portions of these apertures or the entire apertures may be multi-sided in form. The apertures 52 and 63 converge toward one another toward the hinged ends of the sections. Multi-sided shanks 64 65 respectively are slidably supported in the apertures 62 and 63. The shanks 64 and 65 are provided with threaded ends 66 and 67. Notches 69 and 70 are provided in the sides of the sections 55 and 56 intersecting the apertures 62 and 63, preferably near the upper ends thereof. Internally threaded sleeves 71 and 72 are positioned in the notches 69 and 70 respectively and encircle the threaded shank ends 66 and 67. The outer surfaces of the sleeves 69 and 70 are preferably ribbed to accommodate the end of a spring urged screw designed to hold the sleeve in an adjusted position. The screws 73 and 74 are supported by springs 75 and 76 anchored to the sides of the support sections 55 and 56. Thus the adjustment of the nuts 71 and 72 and accordingly the adjustment of the shanks 64 and 65 is retained by the engagement of the resiliently urged screws against the nuts but at the same time the nuts may be manually rotated for adjusting the position of the shanks 64 and 65.

The lower ends of the shanks 64 and 65 are preferably bifurcated or axially slotted to accommodate the perforating wheel 77 and the roll down wheel 79 respectively. Pivots 80 and 81 extend through the respective shank ends to rotatably support these wheels. The roll down wheel 79 is preferably of relatively small diameter as compared with the perforating wheel 77 and thus extends closely adjacent to the center line between the two sections. As a result, the perforating unit may be swung about its supporting shaft into and out of contact with the drum sections 19. Preferably, the perforating wheel 77 extends down into one of the grooves 23 so as to extend entirely through the sheet being perforated. The roll down wheel 79 rolls over the perforations and tends to flatten out the sheet to some extent and also to hold the sheet firmly against'the drum sections.

From the foregoing description, it will be understood that as the sheets are carried over the surfaces of the drum sections 19, they are held under slight tension by the brush 51 and the lines of perforation are formed in the sheet while the sheets are under this tension. It will also be understood that during rotation of the sprockets 12 and 13 on the shaft 11, the brush will be lifted from the surface of the sheet and from the surface of the drum sections just at the time the gripper bars pass beneath the brush.

As indicated in FIGURES 1 and 3 of the drawings, a means is provided for holding the brush out of operative position when it is so desired. A U-shaped bracket 85 is mounted upon the upper surface or base member 33 of the bracket 29 at a point laterally spaced from the aperture 34. A bolt 86 is hingedly connected at 87 between the sides of the U-shaped bracket. The bolt 86 is designed to extend through a cross member 88 forming a part of the frame 10. The bolt 86 fits freely enough in the cross member so that it can move vertically through the cross member as the bracket 29 is raised by the cam 44. Nuts 89 are provided to limit the downward movement of the bracket 29. These nuts may be lowered to hold the bracket 29 in an elevated position if it is so desired. However, in usual practice, a U-shaped spacer is slipped between the cross member 87 and the nuts 89 while the bracket is in elevated position to hold the bracket elevated.

In preferred form, the perforating attachment is provided with an added unit capable of producing skip perforations or die cut perforations, the unit being illustrated in FIGURES 7 and 8 and indicated in general by the numeral 90. The unit 90 includes a sleeve 91 of proper internal diameter to snugly fit about one of the hubs 20 of a drum section 19, the sleeve having an end plate 92 having an apetrure 93 therethrough designed to fit about the shaft 11. The unit includes a disc 94 which is of equal outer diameter to the diameter of the drum sections 19 and which includes a peripheral groove 95 to accommodate an end of the cylindrical sleeve 22 forming the outside of the drum sections 19. A disc 96 of smaller external diameter than that of the disc 94 encircles the sleeve 91 in surface contact with the disc 94. A third disc 97 having a diameter equal to that of the disc 94 encircles the sleeve in surface contact with the disc 96. A fourth disc 99 is positioned in surface contact with the disc 97.

The sleeve 91 is provided with an outwardly extending flange 100 which terminates inwardly of the aperture 101 through the outer disc 99. Cap screws 102 are countersunk into the flange 100 and extend through aligned openings in the disc 97 and 96 and are threaded into the innermost disc 94. The cap screws 102 thus hold the discs 94, 96 and 97 in assembled relation on the sleeve 91. The outermost disc 99 is held in place by countersunk screws 103 which extend into the disc 97.

The opposed surfaces of the discs 94 and 97 are grooved as indicated at 104 and 105 respectively outwardly of the disc 96. These grooves 104 and 104 are designed to accommodate the flanged bases of a series of arcuate segments 107 best illustrated in FIGURES 5 and 6 of the drawings. The segments 107 have arcuate outer surfaces 109 which are of the same radius as the drum sections 19. Each segment 107 includes a groove 110 in its outer arcuate surface and includes oppositely extending flanges 111 and 112 which are designed to engage in the grooves 105 and 104 respectively. Thus, when the segments are engaged in the grooves 104 and 105 they are held from outward movement and form an arcuate grooved surface which is of the same diameter as the drum sections 19.

As is indicated in FIGURE 8 of the drawings, the various segments 107 are of varying arcuate length so that by employing different segments, virtually any total length may be built up. A fixed segment 113 which is substantially semi-circular may be provided where it is always desired to perforate the central portion of the sheet. Obviously, this segment 113 may also be removable and adjustable if desired.

As indicated in FIGURE 8 of the drawings, the various discs forming the unit 90 is provided with a radial slot 114 therein which is at least the width of the diameter of the shaft 11 so that the unit may be attached or removed without removing the shaft. FIGURE 8 shows the unit 90 partially removed from the shaft 11. The outer end of the groove 114 in the unit 90 is preferably widened as indicated at 115 to accommodate the gripper bar 16. The drum sections 19 are grooved as indicated at 118 to accommodate the gripper bar 16. The groove 115 in section 90 and grooves 118 in the drum sections 19 are aligned and are properly positioned to receive the gripper bar during each rotation of the drum. The sections 19 may be adjusted longitudinally of the shaft 11 by loosening the set screws 18 and moving the sections to the proper location. The section 90 may be attached to the end of any section 19, and need not be in the specific location shown.

The purpose of the removable segments 107 is to increase or decrease the length of the groove 110. The groove 110 is designed to accommodate a perforating wheel, and the arcuate surfaces of the segments 107 act to support the sheet as the teeth of the perforating wheel puncture the sheet. By removing a desired number of segments 107, the length of the groove 110 may be reduced to provide a perforated line of a desired length in the sheet. When the segments are removed, the space normally occupied by these segments is of sufficient width to permit the paper to flex so that the teeth of the perforating wheel do not puncture the sheet. In other words, while the perforating wheel engages the sheet throughout its length, the perforations will be provided only throughout the length of the assembled segments 107.

The peripheral portions of the disc 97 is grooved on opposite sides as indicated at 116 and 117. This arrangement provides a space between the periphery of the disc 97 and the surfaces of the segments 107 and of the disc 99. A groove is thus formed between the disc 97 and of the disc 99 which is of proper width to accommodate a perforating wheel 119. The perforating wheel 119 is rotatably supported on a pivot axis 120 mounted upon a shank such as the shank 64 of one of the perforating 7 devices. The perforating wheel 119 is notched to provide spaced teeth which are preferably blunt ended. Thus, as the sheet is drawn between the perforating wheel 119 and the surfaces of the discs 97 and 99, small elongated areas are punched from the sheet to form open perforations. In other words, the' perforating wheel 119 is designed to die cut elongated apertures in the sheet upon movement of the sheet between the unit 90 and the perforating wheel. I

As indicated in FIGURES 7 and of the drawings, angularly spaced apertures 121 are provided through the disc 99 communicating with the groove between the discs 97 and-99. Similar angularly spaced apertures 122 are provided in the disc 97 at'the same radius from the axis of rotation as the apertures 121. The apertures 122 are in staggered relation to the apertures 121 as indicated in FIGURE 10. As the unit 90 is rotated with the shaft 111, the offest apertures tend to create a draft of air which will force the timing areas of paperboard which are diecut from the sheets either to the exterior of the disc 99 or to the groove 116 between the disc 97 and the inserts 107 so as to eject these die out parts.

From the foregoing description it will be apparent that a very practical attachment has been provided which make perforating and creasing operations possible on the oifset printing press. The device functions effectively to simultaneously provide several rows of perforations across the sheet. Rows of perforations which do not extend entirely the length of the sheet may also be provided by properly arranging the removable segments 107. Die cutperforations may also be provided by the unit 90. When the perforating device is not in use, it may be merely pivoted out of operating position and the brush may be swung into elevated position above the level of the sheet in its movement from the press. The attachment is particularly designed on presses having gripper bars supported by endless chains for carrying the sheets through the press. The sheets may be released from the gripper bar as the sheets are drawn around the drum or if desired, the sheets may be carried by the gripper bar to a stacker capable of holding a considerable number of sheets. The entire unit may be easily added to any press of the type described and is adaptable to previously constructed presses as well as new ones.

The apparatus described is capable of perforating sheets with snap out perforations extending to the extreme edges of the sheet so that the edges of the sheet are actually out through without causing the sheets to go out of register. Furthermore, the sheets can be slit through if desired through the use of a razor blade or similar cutting edge supported by a shank in the supporting unit 54 to extend into a groove 23 in a drum section 19. This is dueto the complete control of the sheet during the operation.

In accordance with the patent statutes, I have described the principles of construction and operation of my improvement in perforator attachments for offset presses, and while I have endeavored to set forth the best embodiment thereof, I desireiohave it understood that changes may be made Within the scope of the following claim without departing from the spirit of my invention.

I claim:

A perforating apparatus for use in combination with a roller over which paper sheets may be carried, the apparatus including a shaft rotatably supported parallel to the roller axis and spaced from the roll periphery, a clamp bracket supported by said shaft for movement therewith, a perforating wheel rotatably supported by said bracket, means for. oscillating said shaft to move said perforating wheel toward and away from said roller, a series of angularly spaced supports on said roller inwardly of the periphery thereof, a string of metal tinsel supported by said spaced supports inwardly of the periphery of the roller, but engageable with a sheet as it is rotated with the drum.

References Cited by the Examiner UNITED STATES PATENTS 152,646 6/74 Kellberg 83-32 3 301,249 7/84 Loewenback 83-332 392,262 11/88 Edwards 83-503 525,502. 9/94 Long 83-470 641,725 l/OO Peters 83-100 884,218 4/08 Schwarz 83-659 940,420 11/09 Ayers et al 83-676 989,627 4/11 Meadows 83-345 1,210,454 l/17 Gagne 83-4-70 1,226,168 5/17 Barber 271-68 1,396,318 11/21 Bunger 317-2 1,574,633 2/26 Myover 83-101 1,601,335 9/26 Addison 83-659 1,625,862 4/27 Martin 83-332 1,831,660 11/31 I-Iancock 83-470 1,942,988 'l/34 Taylor 271-68 2,022,433 1l/35 Roemer 83-470 2,023,321 12/35 Gutman 317-2 2,257,336 9/41 ,Feurt 83-345 2,434,624 1/ 48 Peterson 83-482 2,836,243 *5/58 Bedinghaus 83-345 2,940,387 6/60 Pritchard 271-68 3,008,364 1'1/61 Stobb 83-302 FOREIGN PATENTS 459,377 5/ 28 Germany. 3151190 7/29 Great Britain.

ANDREW R. JUHASZ, Primary Examiner.

Images