Folders in a printing press may be operated to run in a “collect” mode in which the folder accumulates a predetermined number of products before passing the accumulated products along. Folders running in collect mode are often fed by multiple webs which were previously accumulated in page groupings from multiple printing groups, for example web offset printing units. The collect cylinder is typically arranged to selectively feed, for example, sheets in a two collect delivery, a three collect delivery, and so on. A two collect refers to a delivery of two sets of sheets at a time, and a three collect involves a delivery of three sets of sheets at a time. Alternatively, the folder may operate in a straight mode, in which the folder does not accumulate any products but rather delivers a set of single sheets at a time to a downstream operation.
Digital printing presses do not require the use of printing plates and thus have a quicker and less expensive turnaround time than traditional lithographic and flexographic printing presses. Further, digital printing presses can produce different images in successive revolutions if a digital print unit is being used including for example, direct imaging pages in an offset printing press. If another type of digital printer is being used, different images may be successively printed on the web as desired. When multiple sets of different pages are produced digitally and when multiple sets of pages with different subject matter can be selectably sequenced onto one web, the associated folders cannot accumulate or “collect” a varying number of products in the traditional manner. Consequently, the capabilities of a digital printing press would be greatly reduced when using traditional collect mode folders.
U.S. Publication No. 2007/0135286, hereby incorporated by reference herein, discloses a folder having a collect cylinder mounted for rotation and a collect cylinder drive mechanism for rotating the collect cylinder.
U.S. Pat. No. 4,381,106, hereby incorporated by reference herein, describes a known arrangement for a collect cylinder having a non-rotating cam and a rotating cam mask. A gripper for gripping a product is opened and closed by a cam follower that engages a cam surface of a fixed, non-rotating cam. The cam surface is profiled to coordinate the gripper opening and closing operations with the location of the gripper at product taking and product release stations respectively. A rotating mask has camming surfaces that selectively mask the surface profile of the cam, to thereby permit or prevent operation of the gripper, to provide a selected mode of operation.
U.S. Pat. No. 7,744,518, hereby incorporated by reference herein, discloses a folder that includes a device for cutting sheets from a web of paper, a folding cylinder provided with movable retention devices and movable blades for folding the sheets cut from the web, a cam for controlling the movement of the movable retention devices by contact with cam followers, a cam for controlling the movement of the tucking blades by contact with cam follower, and at least one covering cam. The covering cam includes two semi-cams which can each be moved radially between a retracted position and an extracted position, the covering cam being in a configuration for straight operation when the semi-cams are in a retracted position and in a configuration for collect operation when the semi-cams are in an extracted position.
The present invention provides a printing press including at least one printing unit for printing on a running web, a cutting cylinder for cutting the web into sheets and a folder for folding sheets cut from the web. The folder includes a collect cylinder for accumulating a number of sheets at a collect location, a folding cylinder for folding the accumulated number of sheets received from the collect location to form a folded section, a cam arrangement including a supplementary cam device for controlling the number of sheets collected on the collect cylinder and an actuator for actuating the supplementary cam device.
The present invention also provides a method of forming a printed product. The method includes the steps of printing a running web with at least one printing unit, cutting a web into sheets, collecting a number of sheets on a collect cylinder at a collect location, actuating a supplementary cam device to control the number of sheets collected at the collect location and folding the number of sheets received from the collect cylinder to form a section.
The present invention further provides a method of digitally printing a web and forming a printed product from the web. The method includes the steps of printing a web in a sequence with at least one digital printing unit, cutting the web into a plurality of sheets, collecting a first number of sheets on a collect cylinder at a first collect location, collecting a second number of sheets on the collect cylinder and changing the number of sheets collected from the first number to the second number while the web is running
The present invention applies folder technology to digital printed products approaching web offset speeds and exceeding speeds of sheeters, collators and buckle folders.
The present invention provides for the production of multi-page newspapers with a selectable number of pages from digitally printed sources.
The present invention provides an actuatable, selectable collect and folding cylinder. The present invention further provides a transfer cylinder.
In a typical collect folder, a cam mask rotates in the collect mode to selectively determine which collected groups of products are complete and are therefore ready to fold off into the jaw. In the present folder, a supplementary cam device is moved into position by an actuator, so the number of products to be collected before folding off is selectable to match the number of digitally printed pages that have been printed, which can vary from job to job, version to version or copy to copy.
Conventional folders do not include a transfer cylinder. Including a transfer cylinder eliminates the creation of “macaroni.” Macaroni, as known in the art, are slivers of paper resulting from a new cut made adjacent to one or more already collected products, thereby severing the previously collected products. In accordance with the present invention, the cutting cylinder cuts the web into printed products against the transfer cylinder, the transfer cylinder then transfers each individual product to the collect cylinder after the printed product has been cut, thus, there are no previously cut pages at the point of cutting a new sheet. As a result, the collect cylinder does not serve as a counter cylinder to the cutting cylinder, the collect cylinder simply collects printed products already cut from the web.
A preferred embodiment of the present invention is described below by reference to the following drawings, in which:
A printing press according to the present invention is configured to produce printed products such as newspapers, for example, tabloid or broadsheet newspapers, from a web containing pages printed sequentially on a single web. The pages are printed in a sequence needed to produce the desired final product or newspaper. The printed products and newspapers may include a plurality of sections. The number of sections per newspaper and the number of pages in each section are fully variable in accordance with a preferred embodiment of the present invention.
Broadsheet newspapers printed on a digital printing press are produced with the newspaper columns laid out across the length of a web, along the direction of web travel. The vertical spine of the broadsheet newspaper is produced in a folder, for example, a jaw folder, by a fold extending across the web. Other types of folders may also be used. The horizontal fold across the middle of the height of the broadsheet newspaper is made parallel with the direction of web and product travel. The second fold may be produced by a further folder, for example, a quarter folder or chopper. Tabloid newspapers printed on a digital printing press are also produced with the newspaper pages laid out across the length of the web, along the direction of web travel. The vertical spine of the tabloid newspaper is produced in a folder, for example, a jaw folder, by a fold extending across the web. As known in the art, tabloid newspapers usually include only one fold, the vertical spine. Other types of folders may also be used.
As discussed above, sheets are printed with images printed along the length of web 12, in the direction of web travel Y, thereby producing a panorama sheet 114. (See
Digital print engines may print pages of a desired final product in a sequence on the web so final products may be made on a copy per copy basis in contrast to traditional offset printing methods in which a section or portion of a final product is made in multiples and the different sections are later combined with each other. For example, when printing a newspaper, each page of the newspaper may be digitally printed on the web before the digital print engines start printing a second copy or version of the newspaper, thereby forming one complete newspaper from sequential images on the web. The digital print engines can begin printing the second newspaper without stopping the press to change folder modes. In addition, if, for example, newspaper sections are desired, an entire first section may be digitally printed on the web in sequence before second, third and further successive sections begin printing, regardless of the number of pages in the different sections. In another alternative, different sections may be printed in a desired sequence and formed simultaneously, regardless of the number of pages desired in each section. Thus, different sections can be digitally printed at any time and in any order as desired by the press operator. Further flexibility provided by the digital print engines also provides for different sections to be printed in duplicates or multiples as desired. For example, a first newspaper section A, may be collected at each gripping location on a collect cylinder and folded off into a jaw cylinder. A second newspaper section B may then be collected at each gripping location and folded into the jaw cylinder. Successive printing of section A and section B can occur without stopping the press regardless of the number of sheets collected in each section.
Web 12 enters folder 120 and is cut into sheets or printed products by a cutting cylinder 50 having cutting blades 52. Folder 120 includes a one-around cutting cylinder 50, as known in the art, one around cylinder has circumference which supports a single sheet 114. Folder 120 also includes a two around transfer cylinder 54, a two around collect cylinder 60, a two around jaw cylinder 70 and a fan wheel 74. Other embodiments and configurations of folder 120 are also possible and will be described below with respect to
Cutting cylinder 50 works in conjunction with a transfer cylinder 54. Transfer cylinder 54 includes two pins 56 and two cutting rubbers 58. Pins 56 grip a lead edge of a new sheet to be cut from web 12. Pins 56 may be any form of sheet gripping device for example, pins, mechanical grippers or vacuum grippers. Cutting blade 52 extends and cuts web 12 into sheets 114 against the surface of transfer cylinder 54. Cutting rubber 58 serves as a counteracting surface for cutting blade 52.
Sheets 114 are then transferred to collect cylinder 60. Collect cylinder 60 includes two pins 62, which may also be any type of sheet gripping device, for example, pins or mechanical grippers and two tucking blades 64 for folding off sheet(s) 114. Both pins 62 and tucking blades 64 are controlled by cam arrangements. Jaw cylinder 70 includes two jaws 72 for receiving sheets from collect cylinder 60. Tucking blades 64 tuck sheets 114 into jaws 72 of jaw cylinder 70.
In accordance with a feature of the present invention, collect cylinder 60 includes actuatable cam arrangements 80 (See
As shown in
In order for the cylinders to operate in collect mode, each tucking blade 64, 64′ and each pin 62, 62′ must be inhibited from releasing and tucking the collected sheets 114N. In a preferred embodiment, each cam arrangement 80, 80′ includes a supplementary, actuatable cam device. In this embodiment, actuatable cam masks 68, 68′ are used to cover fixed cams 66, 66′ respectively, thereby changing the paths of cam followers 65, 65′. The profile of cam masks 68, 68′, subsequently inhibits the tucking blade 64 and pin 62 from tucking and releasing sheets. As shown in
An actuator, for example, pneumatic cylinder 69 is connected to controller 110 and cam masks 68, 68′. Each mask 68, 68′ may have a corresponding actuator connected thereto and to controller 110. When desired, pneumatic cylinder 69 (
In a typical collect folder, cam mask 68 rotates in the collect mode until products are complete and are therefore ready to fold off into the jaw. The number of collected products is set, for example, two collect mode, three collect mode, etc. and does not change between copies. In accordance with a preferred embodiment of the present invention, cam mask 68 is moved into position by an actuator, for example, pneumatic cylinder 69, so that the number of sheets 114 collected before folding is selectable to match the number of digitally printed pages printed on web 12. The actuator may be pneumatic, hydraulic or servo driven, for example. The number of digitally printed pages may vary from job to job or copy to copy. By providing a supplementary cam device and actuator, faster and more flexible changes to the operating mode of the folder and collect cylinder, and number of sheets being collected are possible. Thus, a first section being formed may include 8 pages while a second section being formed may include 4 pages.
Cam arrangements 80, 80′ and supplementary cam devices (shown in
Cam arrangements 80, 80′ and supplementary cam devices for pin 62′are actuated to release and fold off sheets 1142, 1144 into jaw 72′ once both sheets are collected at pin 62′ to form a section 116B. (See
In accordance with another feature of the present invention, a transfer cylinder is provided. Transfer cylinder 54 advantageously eliminates double cuts and slivers in sheets 114 also known in the art as “macaroni.” In conventional folders, sheets 114 are cut directly on the collect cylinder. Thus, a pin is gripping the lead edge of one previously cut sheet and the lead edge of a second soon-to-be cut sheet. The cutting cylinder then makes a new cut in order to cut the second sheet against the collect cylinder, often times cutting an edge of the first sheet again. This second cut on the first sheet is undesirable. As a result, providing a transfer cylinder 54 for cutting each sheet 114, prior to collecting the sheets 114 on collect cylinder 60 prevents any double cuts or “macaroni.”
In another preferred embodiment, shown in
In a further preferred embodiment shown in
In each of the previously described embodiments, a controller 110 may be used to automatically control the supplemental cam devices and actuators. For example, in
By providing selectably, actuatable cam arrangements, supplementary cam devices and actuators much higher folder speeds can be reached than with newspaper production equipment utilizing sheet accumulation and buckle folding principles. The higher speeds yield greater outputs, especially when combined with high speed digital printing presses. The actuatable cam arrangements when used in conjunction with a digital printing press provide folder flexibility. Folders may be switched from collect mode to straight mode on a per copy or per product basis.
As shown in
After sheets 1141, 1142 are combined at pins 62, 62′ 62″ the sheets 1141, 1142 are transferred to jaw cylinder 70 and subsequently to fan 74 wheel. Fan 74 includes a plurality of fan blades 76. A folded collection of sheets or section 116 is received between each fan blade 76. Fan 74 then deposits printed products 116 in a delivery stream 80 for further processing. Each pin 62, 62′, 62″ may be collecting sheets having different images thereby forming three different sections 116. However, as desired, each pin 62, 62′, 62″ may be collecting identical sheets 1141, 1142, thereby producing three identical sections 116.
When a single sheet 114 is collected, the resulting folded sheet or section 116 includes four pages. (
Other preferred embodiments of the present invention may include, printing and forming consecutive newspaper sections on the web and in the folder to form a single copy directly off folder, the sections may have the same page counts or different page counts. Sections produced from folder 120 may be subsequently accumulated in a post-fold accumulator to form a multi-section printed product that is wrapped or quarterfolded. Each section or folded printed product may also be stitched after the section has accumulated all of the desired number of pages.
In the preceding specification, the invention has been described with reference to specific exemplary embodiments and examples thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of invention as set forth in the claims that follow. The specification and drawings are accordingly to be regarded in an illustrative manner rather than a restrictive sense.
Priority is hereby claimed to U.S. Provisional Application No. 61/503,276 filed Jun. 30, 2011, and hereby incorporated by reference herein. The present invention relates to printing presses and more particularly to folders in a printing press.
Number | Date | Country | |
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61503276 | Jun 2011 | US |