CA1154304A - Sheet transfer cylinder in rotary printing machines - Google Patents
Sheet transfer cylinder in rotary printing machinesInfo
- Publication number
- CA1154304A CA1154304A CA000371341A CA371341A CA1154304A CA 1154304 A CA1154304 A CA 1154304A CA 000371341 A CA000371341 A CA 000371341A CA 371341 A CA371341 A CA 371341A CA 1154304 A CA1154304 A CA 1154304A
- Authority
- CA
- Canada
- Prior art keywords
- warp
- per
- tex
- fabric
- weft
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41F—PRINTING MACHINES OR PRESSES
- B41F22/00—Means preventing smudging of machine parts or printed articles
Landscapes
- Treatment Of Fiber Materials (AREA)
- Feeding Of Articles By Means Other Than Belts Or Rollers (AREA)
- Sheets, Magazines, And Separation Thereof (AREA)
- Supply, Installation And Extraction Of Printed Sheets Or Plates (AREA)
- Yarns And Mechanical Finishing Of Yarns Or Ropes (AREA)
- Machines For Manufacturing Corrugated Board In Mechanical Paper-Making Processes (AREA)
- Rolls And Other Rotary Bodies (AREA)
Abstract
Abstract of the Disclosure:
A sheet transfer cylinder of a rotary printing machine having a cylinder body with a surface whereon means are provided for preventing smearing of a freshly printed underside of a sheet being transfered by the sheet trans-fer cylinder, the improvement wherein the smear-preventing means include a covering applied to the cylinder body and formed of textile material having rough surface structure and being compressible due to a presence of air occlusions therein.
A sheet transfer cylinder of a rotary printing machine having a cylinder body with a surface whereon means are provided for preventing smearing of a freshly printed underside of a sheet being transfered by the sheet trans-fer cylinder, the improvement wherein the smear-preventing means include a covering applied to the cylinder body and formed of textile material having rough surface structure and being compressible due to a presence of air occlusions therein.
Description
3~
SHEE~ ANSFER CYLINDER_IN_ROTARY PRINTING MACHINES
SPECIFICATION:
The invention relates to a sheet transfer cylinder in rotary printing machines and more particularly, a sheet delivery cylinder which is mounted on a sprocket-wheel shaft of a chain delivery system and has a cylinder body on the surface of which, means are provided for preventing smearing of a freshly printed underside of a sheet during transfer of the sheet.
During transfer of the freshly printed sheet within the printing machine, in accordance with the disposition of the sheet transfer drum, the freshly printed side of the sheet to be transfered comes to lie upon the surface of the cylinder body of the sheet transfer cylinder. If no special precautions or measures are taken, contaot by not-yet dried ink with the cylinder-body surface causes smearing of the printed image. Exacting printing jobs thereby beco~e nonusable ~or the most part.
A sheet delivery cylinder heretofore known from German Patent (DE-PS) 1 561 043 is constructed with a double wall and has a covering formed of porous and air-permeable material. Air i~ blown into the hollow space existing between the double wall. ~he air passes through the air-.
permeable covering and produces an air cushion between theouter surface of the cylinder body of the sheet transfer cylinder and the freshly printed underside of the sheet which is to be transfered. The air cushion prevents smearing of the printed image.
The heretofore known shee-t delivery cylinder has the dis-advantage that the manufacture thereof is expensive.
Large quantities of compressed air are necessary to produce the air cushion. In addition to the cost of the device itself, a very high energy requirement must be reckoned with. In addition thereto, the condition of the air within the printing plant or print shop is undesirably affected thereby. An undesired introduction of heat into the printing machine also occurs, moreover, with the required large quantity oE air, which can result in distortion or warping of the paper sheets. The use of such heretofore known sheet delivery cylinders therefore frequently necessitates the additional provision of cooling and humidifying equip-ment for the blowing air which becomes cost-intensified.
In U.S. Patent 3,126,826, column 3, beginning with line ~9 thereof, a covering for a sheet transfer cylinder is described which is formed as glass-bead cloth. The glass beads are, for example secured by adhesive to a rubber cloth and form, with the adhesive material, a closed, non-porous surface. The surface of this heretofore known covering 3~
exhibits varying ink transfer characteristics. Whereas the rounded corners of the glass beads again readily surrender to the sheet the ink which had been previously accepted and carried thereby, the troughs or valleys located between the glass beads and formed of adhesive material and rubber solvent tend to have ink build up therein. A consequence thereof is that such glass-bead cloths must be washed very often which causes the individual glass beads to loosen very easily from the adhesive connection thereof. In the long run, glass-bead cloths do not exhibit any satisfactory results with respect to preventing smearing. The heretofore known glass-bead clothes are useable, in any event, only limitedly on sheet delivery cylinders because, with the transition of the chain gripper from the circular path of the sprocket wheel to the straight path of the chain, a speed differing slightly from the peripheral or surface speed of the cylinder body of the sheet delivery cylinder is ~
imposed upon the sheet being transferred. ~he shifting of the freshly printed underside of the sheet relative to the covering, namely the glass-bead cloth, which results from the slight difference in speed, causes smearing of the printed image.
It is accordingly an object of the invention to provide, in a sheet transfer cylinder of a rotary printing machine, a cylinder body having a covering which is capable of being , L3~
produced by relatively simple means and relatively simply securable on the sur~ace o~ the cylinder body, the transfer-cylinder covering being effective for avoiding smearing and scratching of the wet printed image even when there is relative motion between the freshly printed underside of the sheet and the transfer-cylinder covering.
It is another object of the invention, to provide such a transfer-cylinder covering which will permit trouble-free printing of editions of at least 500,000 printings without any deterioration of the printed image becoming noticeable.
It is a further object of the invention to provide such a transfer-cylinder covering which can be cleaned in a relatively simple manner while it remains on the sheet transfer cylinder.
With the foregoing and other objects in view, there is provided, in accordance with the invention, a sheet transfer cylinder of a rotary printing machine having a cylinder body with a surface whereon means are provided for preventing smearing of a freshly printed underside of a sheet being transfered by the sheet transfer cylinder, the smear-preventing means comprising a covering applied to the cylinder body and formed of twill material having a rough sur~ace structure and being compressible due to a presence of air occlusions therein, with a warp thread count of substantially 24.7 to 50.4 per cm and a weft count of substantially 14~5 to 22.7 per cmO
Long lasting tests have produced the surprising evidence that it is sufficient to cover the peripheral or casing 3~
surface of a sheet ~ransfer cylinder or casing surface of a sheet transfer cylinder solely with a compressible textile material so as to be able to transfer freshly prin-ted sheets without smearing. Even with the use of this covering on sheet delivery cylinders during which relative motion inevitably occurs between the freshly printed sheet under-side and the covering of the cylinder, no scratching and no smearing of the printing image could be detected. What is especially surprising, is that these textile-type coverings retain the non-ink-smearing characteristics or the printing-image preserving transferability thereof over a great number of printing or over a large printing edition.
Various types of textile fabrics have been tested in order to determine those parameters or characteristics thereof which render them particularly suitable for the purpose of this invention.
Example A
The textile material which was found to be best suited as a cylinder covering for retaining the non-ink-smearing characteristics or the printing-image-preserving transfer-ability thereof over a great number of printings is a twill fabric having a warp thread count per cm of substantially 33.4 and a weft thread count per cm of substantially lg.0, a normal-condition warp fineness of substantially 47.4 tex or, as expressed in terms of yarn number substantially 21.1, f~ L~
and a weft fineness of substantially 48~1 tex or, also as expressed in terms of yarn number - substantially 20~8/
and warp liftings per cm of substantially 158~ 7 ~ Both the warp and the weft threads are formed of pure cotton. The 5 weight per unit surface area of this textile material is 293 g/m , the raw state density thereof is 0. 314 g/cm and the percentage by volume of the pores formed therein is 79 ~ 6 % ~
Twc other textile materials were found also te be well suited for the purposes of the inven-tion although not quite as.good as the just-mentioned textile material.
Example B
One of these other well suited textile materials is a twill fabric having a warp -thread count per cm of sub-stantially 50. 4 and a weft thread count per cm of sub-stantially 22~7r a normal-condition warp fineness of substantially 27~4 -tex or yarn number of substantiall.y 36~5 and a weft fineness of substantially 43 ~ 1 tex or yarn number of substantially 28~2~ and warp liftings per cm of 20 substantially 286~0~ Both the warp and the weft threads are also formed of pure cotton. The weigh-t per unit surface area of this textile material is 261 g/m , the raw s-tate density thereof is 0. 381 g/cm , and the percentage 24 by volume of the pores formed therein is 79 ~ 6~o ~
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Example C
The second of the other two well suited materials is also a twill fabric which, however, has a warp thread count per cm of substantially 32.5 and a weft thread count per cm of substantially 19.4, a normal-condition warp fineness of substantially 47.3 tex or yarn number of substantially 21.1, and a weft fineness of substantially 64.1 tex or yarn number of substantially 15.6, and warp liftings per cm 2 of substantially 157.6. Both the warp and the weft threads are also formed of pure cotton. The weight per unit surface area of this textile materials is 315 g/m2, the raw state density thereof is 0.422 g/m2, and the percentage by volume of the pores formed therein is 72.6%.
Less suitable for the purposes of the invention and, indeed, critical though nevertheless usable there~ore are two textile fabrics respectively, exhibiting a great degree of profiling or a low working surface and a great extent of smoothness.
~ ~ '.
: ' The textile material having the greatest profiling o~ all the fabrics tested is also a twill fabric which, however, has a warp thread count of substantially 24.7 per cm and a weft thread count of substantially 15.0 per cm, a normal-condition warp fineness of substantially 94.8 tex or yarn number of 10.5 and a weft fineness of substantially 68.6 tex or yarn number of substan-3~3~
tially 14.6, and warp liftings of substan-tially 92.6 per cm2. The warp is formed oE pure cotton but the weft is formed of a mixture of polyester and co-tton. The weight per unit surface area of this textile ma-terial is 368 g/m2, the raw state density thereof is 0.335 g/c3, and the percentage by volume of the pores formed therein is 77.7%.
EXAMPLE E
_ The textile material exhibiting great smoothness i.e. limited profiling, is a cross-twill fabric and has a warp thread count of substantially 25.0 per cm and a weft thread count of substantially 14.5 per cm, a normal-condition warp fineness of substantially 87.7 tex or yarn number of substantially 11.4, and a we:Et fineness of substantilly 75.2 tex or yarn number of substantially 13.3, and warp liftings of substantially 90.6 per cm2. Both the weft and the warp threads are formed of pure cot-ton. The weight per unit surEace area of this textile material is 366 g/m2 the raw state density thereof is 0.352 g/cm3, and the percentage by volume of the pores formed therein is 77.1%.
Thus the textile fabrics of Example D and E are critical with respect to the efficient operation thereof for the purposes of the invention and have limiting characteristics at opposite ends of the range of characteristics manifested by the tested materials usable in accordance with the invention.
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Example F
A textile material which was found to have poor runability for the intended use in accordance with the invention is a linen fabric which has a warp thre^~--d^ count of substantially 16.2 cm and a weft thread coun-t of substant-ially 13.9 per cm and a weft thread count of substantially 8.6, and a weft fineness of substantially 122.2 tex or ~:
yarn number of substantially ~.2, and warp liftings of substantially 112.62. Both the weft threads and the warp threads are Eormed of pure wool. The weight per unit surface area of this textile material is 445 g/m2, ~, the raw state density thereof is 0.400 g/cm3, and the percentage by volume of the pores formed therein is 69.7~.
The textile material oE Example F has the smoothest surface of all of the foregoing textile materials tested.
Considering that fact and that the material of Example E also has a very smooth surface and is critical with respect to the runability thereof for the intended use, and further considering that the textile material of Example D has the roughest profiling of the surface structure thereof and is also critical with respect to the runability thereof for the intended use, it has become apparent that the profiling of the surface structure of the -textile fabric plays an important role in the selection of the fabric according to the inven-tion. Eabrics with a very smooth surface such as that of Example F, and fabrics with very strong or rough profiling and low working surface, accordingly, namely greater than that of Example D, are consequently not suited for attaining the objectives of the invention of the instant application.
Among the foregoing examplesof textile fabrics, that o Example B had the least thickness while that of Example F
was thickest. In compression tests administered to all of the fabrics, that of Example D had the greatest compressi-bility followed by Examples A, E, F, B and C of sequentially lower compressibility.
With respect to the parameter warp thread liftings per cm , it is noted that the respective value thereof is a function of the amount of thread per cm of warp and weft, as well as of the weave. Of the six fabrics of the examples, those of Example A, B, C and D are twill weave K - /S, that of Example E is cross-twill weave XK ~, and that of the undesirable Example F, linen weave L~
It ha~s been surprisingly found from the testing of the various textile materials that when the thread fineness of the optimally functioning textile fabrics of Examples A, B and C are exceeded or the thread count reduced, an additional parameter or characteristic of the textile fabric must be varied i.e. the weave cross-twill of Example E or the composi-tion of the -thread, namely the weft of polyester/cotton of Example D in order to attain at least reasonable functioning of such a textile material.
A dry rub-down is ordinarily sufficient for cleaning these textile-type coverings. Ink residues, which adhere to -the tipS of the textile or web par-ts projecting out of the supporting covering surface can accordingly be rubbed off with ease. At greater intervals, wet cleaning by conven-tional roller and form washing means is also possible.
Tests have established, however, that such wet cleaning of the textile-type covering is unnecessary under 1,000,000 printings.
In accordance with another feature of the invention, the covering is formed of a web of yarn, fleece material, tufted material or knitted fabric.
In accordance with a further feature of the invention, the covering is formed of a tightly woven textile material having, at least on one side thereof, a tufted and brushed surface, respectively.
From knowledge which has been gained, the operation of the invention of the instant application is based upon two mutually assisting operations. For one, the freshly printed underside of the sheet initially contacts a multiplicity of yielding supporting points of the rough surface structure of the textile material quite in contrast to'the glass-bead cloths wherein the supporting domes or prominences, in this regard, are non-yielding. For the other, during the further close approach of the sheet to the peripheral surface, an air cushion is inevitably formed due to the yieldabili-ty of the supporting points of the textile material, because the structure of the textile material impedes shifting of the air in every lateral direction. As the sheet approaches even more closely to the covering, an overpressure or excess pressure is produced, respectively, between the sheet and the peripheral surface of the cylinder body and between the sheet and the underside of the covering in the case where the latter is reinforced on one side thereof. It has been found that both this air cushion as well as the pro-truding textile parts, which are movable within given limits, carry the freshly printed underside of the sheet in a manner that a relative movement, such as inevitably occurs in a chain delivery system, cannot produce smearing and scratching of the printed image.
For better handling and in order to prevent the formation of folds when putting on a covering according to the invention, the side of the covering facing or lying on the cylinder body surface is reinforced.
In accordance with an additional feature of the invention, the covering is formed of brushed denim material. Even the 25 most del:Lcate printing could be fed without quality loss to ~
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the sheet delivery stack by such a covering. Basically, however, all textile material i.e. any fiber-containing material whether ornot it has a linen, twill or satin cross-weave or is formed of a knit, can be used for the covering material. Likewise, tufted material is also able to be so used.
In accordance with yet another feature of the invention, burr-type closures are included at respective ends of the covering for readily releasably fastening the covering to the cylinder body.
In accordance with yet a further feature of the invention, the covering is readily releasably secured by adhesive to the surface of the cylinder body~
In accordance with yet an additional feature of the invention, the cylinder is a sheet delivery cylinder, and the covering is disposed on the surface of -the cylinder body of the sheet delivery cylinder.
In accordance with an added feature of the invention, -the covering is formed of a twill fabric.
In accordance with another feature of the invention, the fabric has a warp thread count of from substantially 24.7 to substantially 50.4 per cm and a weft thread count of from substantially 14.5 to subs-tantially 22.7 per cm.
In accordance with a further feature of the invention, the warp of the fabric has a normal condition fineness ranging from substantially 27.~ tex to substantially 94.8 tex and the weft of the fabric from substantially 43.1 tex to substantially 75.2 tex.
In accordance with yet another fea-ture of the invention, the fabric has warp thread liftings per cm ranging from substantially 90.6 to substantially 286Ø
In accordance with yet a further feature of the invention, the fabric has a cross-twill weave having a warp thread count of substantially 25.0 and a weft thread count of substantially 14.5 per cm, a normal condition warp fineness of substantially 87.7 tex and weEt fineness of substantially 75.2 tex, and warp liftlngs per cm of substantially 90.6.
In accordance with yet an additional feature of the invention, the fabric has a warp thread count of substantially 24.7 and a weft thread count of substantially 15.0 per cm, a normal condition warp fineness of substantially 94.8 tex and weft fineness of substantially 68.6 tex, and warp liftings per cm of substantially 92.6.
In accordance with yet an added feature of the invention, the fabric has a warp thread count of substantially 50.4 and a weft :thread count of substantially 22.7 per cm, a normal-condition warp fineness of substantially 27.4 tex and weft fineness of substantially 43.1 tex, and warp liftings per cm of substantially 286Ø
In accordance with an alternate feature of the invention, the fabric has a warp thread count per cm of substantially 33.4 and a weEt thread count per cm of substantially 19.0, a normal-condition warp fineness of substantially 47.4 tex and weft fineness of substantially 48.1 tex, and warp liftings per cm of substantially 158.7.
In accordance with still a further feature of the invention, the fabric has a warp thread count per cm of substantially 32.5 and a weft thread count per cm of substantially 19.4, a normal-condition warp fineness of substantially 47.3 tex and weft fineness of substantially 64.1 tex, and warp liftings per cm of substantially 157.6.
In accordance with again another feature of the invention, the fabric is formed with pores having a precent by volume 15 ranging from substantially 72.6 to substantially 79.6.
In accordance with again a further :Eeature oE the invention, the fabric has a weight per unit surface area ranging from substantially 261 to substantially 368 g/m .
~ In accordance with again an alternate feature of the ; 20 invention, the warp is of pure cotton and the weft is either of pure cotton or of a mixture of polyester and cotton.
In accordance with a concomitant feature of the invention, the rotary printing machine has a sheet transfer cylinder disposed between respective printing units for transfering printed sheets from one unit to the other, the sheet transEer ~f~
cylinder comprising a cylinder body, and a smear-preventing covering applied to the cylindrical surface of the body, the covering being formed of textile material having rough surface structure and being compressible due to a presence of air occlusions therein.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a sheet transfer cylinder in rotary printing machines, it is nevertheless not intended to be limi-ted to the details shown, since various moclifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:
FIG. 1 is a diagrammatic side elevational view of a chain delivery system;
FIG 2 is an enlarged fragmentary view, partly in section, of FIG 1 showing a sheet delivery cylinder on the chain sprocket wheel shaft, a covering according to the invention being shown carried by the cylinder body of the sheet delivery cylinderi FIG. 3 is an even further enlarged fragmentary view of FIG. 2 showing the covering of the sheet delivery cylinder in greater detail;
FIG. 4 is another enlarged fragmentary view of FIG. 2 showing the means of fastening the covering to the cylinder body of the sheet delivery cylinder; and FIG. 5 is a diagrammatic side elevational view, partly in section, of sheet transfer cylinders with coverings accord- :
ing to the invention, the transfer cylinders being disposed between printing units of a rotary printing machine.
Reffering now to the drawing and first, particularly, to FIG. 1 thereof, there is shown an impression cylinder 1 of the last printing uni-t of a multicolor sheet-fed rotary offset printin~ machine which trans~ersa printed sheet 2 to a gripper bridge 3 of a chain delivery 4. In t~is regara, a sheet delivery cylinder 6 provided on the sprocket- -wheel shaft 6 disposed closer to the impression cylinder 1 advances the sheet 2 with the freshly printed side thereof facing the sheet delivery cylinder 5, during the transfer operation. The gripper bridges 3 transfer the surrendered sheet 2 to the sheet delivery stack 7.
As shown in FIG. 2, -the peripheral or shell surface 8 of the sheet delivery cylinder 5 is covered with a covering 9, which is formed of textile material having a rough surface a~
structure and provided with air occlusions rendering the textile material compressible. This textile material can be produced as a web of yarn, a reinforced or stiffened fleece material, a tufted material or a knitted fabric.
In the embodiment of the invention specifically described herein and illustrated in the drawing r the covering is formed of brushed denim material.
FIG. 3 is illustrative of the mode of operation of a covering according to the invention. Upon the surrender of the sheet 2 by the impression cylinder 1 to the sheet del~very cylinder 5, the textile-type covering 9 is sli~htly compressed due to the stress in the sheet 2. This occurs, among other reasons, due to the fact that the sheet 2 remains adhered to the non-illustrated blanket cylinder of the last printing unit and must be withdrawn from the surface thereof : by the use of a given force. The hugging or close approach of the sheet 2 gripped by the gripper bridges 3 to the covering 9 works in two ways. First, the freshly printed shee-t underside hugs or makes close contact with the yielding supporting parts of the rough surface structure of the covering material. Then, due to the hereinafore mentioned stress in the sheet 2, a compression or pressing-in of these yielding supporting parts of the surface structure of the covering 9 is effected. Since the web or texture of the covering 9 impedes lateral escape of the air, an air cushion with excess pressure or overpressure is formed. Both the yielding raised web parts and the air cushion together support the sheet 2 guided by the gripper bridges 3 at the freshly printed side of the sheet 2. The instant that the gripper bridges 3 holding the end of the sheet 2 then leave the circular path about the sheet delivery cylinder 5 and run into the straight chain path of the chain delivery 4, the speed thereof diminishes slightly. A consequence thereof is that the sheet 2 transfered by the sheet delivery cylinder 5 performs a slight movement relative to the peripheral or outer cylindrical surface of the sheet delivery cylinder 5.
Notwithstanding this relative motion, no scratching or smearing of the printing image is effected. The textile-type covering ~ is able to be fastened to the side walls 10 defining -the channel or slot 11 of the sheet delivery cylinder 5 in a relatively simple manner by means of burr-like closures or fasteners 12 shown in FIG. ~. The latter are formed, on the one side, of an adhesive foil provided with hooks and, on the other side, of an adhesive foil studded with eyes.
One of these adhesive foils is fastened to the textile covering 9, the other to the wall 10 of the cylinder channel 11. Merely by pressing the one part of the burr-like fastener or closure 12 to the other part thereof, the covering 9 is tightly clamped. The burr-like closure 12 thus permits clamping and removal of the covering 9 in a relatively simple manner by hand i.e. without the aid of tools.
The fastening of the ends of the covering 9 by means of burr-like closures can also be effected at other parts of the wall of the sheet delivery cylinder 5 as, indeed, at the side walls 10 defining the channel 11. Li.kewise, the possibility exists of providing a burr-like closure part on the sheet delivery cylinder 5, the te~tile-type covering 9 adhering directly thereto.
The use of the covering 9 in accordance with the invention is ; not limited to the sheet delivery cy:Linder. On the contrary, such covering 9, as shown in FIG. 5, can find utility also in sheet transfer cylinders.
In the illus-trated embodimen-t of FIG.. 5, a s-torage cylinder 15 surrenders the previously printed sheet 2 to a sheet -transfer cylinder 16. Since the latter must transfer the sheet 2 with the printed side ihereof facing it, a textile-type covering 9 in accordance with the invention is provided thereon. The impression cylinder 17 takes over the sheet
SHEE~ ANSFER CYLINDER_IN_ROTARY PRINTING MACHINES
SPECIFICATION:
The invention relates to a sheet transfer cylinder in rotary printing machines and more particularly, a sheet delivery cylinder which is mounted on a sprocket-wheel shaft of a chain delivery system and has a cylinder body on the surface of which, means are provided for preventing smearing of a freshly printed underside of a sheet during transfer of the sheet.
During transfer of the freshly printed sheet within the printing machine, in accordance with the disposition of the sheet transfer drum, the freshly printed side of the sheet to be transfered comes to lie upon the surface of the cylinder body of the sheet transfer cylinder. If no special precautions or measures are taken, contaot by not-yet dried ink with the cylinder-body surface causes smearing of the printed image. Exacting printing jobs thereby beco~e nonusable ~or the most part.
A sheet delivery cylinder heretofore known from German Patent (DE-PS) 1 561 043 is constructed with a double wall and has a covering formed of porous and air-permeable material. Air i~ blown into the hollow space existing between the double wall. ~he air passes through the air-.
permeable covering and produces an air cushion between theouter surface of the cylinder body of the sheet transfer cylinder and the freshly printed underside of the sheet which is to be transfered. The air cushion prevents smearing of the printed image.
The heretofore known shee-t delivery cylinder has the dis-advantage that the manufacture thereof is expensive.
Large quantities of compressed air are necessary to produce the air cushion. In addition to the cost of the device itself, a very high energy requirement must be reckoned with. In addition thereto, the condition of the air within the printing plant or print shop is undesirably affected thereby. An undesired introduction of heat into the printing machine also occurs, moreover, with the required large quantity oE air, which can result in distortion or warping of the paper sheets. The use of such heretofore known sheet delivery cylinders therefore frequently necessitates the additional provision of cooling and humidifying equip-ment for the blowing air which becomes cost-intensified.
In U.S. Patent 3,126,826, column 3, beginning with line ~9 thereof, a covering for a sheet transfer cylinder is described which is formed as glass-bead cloth. The glass beads are, for example secured by adhesive to a rubber cloth and form, with the adhesive material, a closed, non-porous surface. The surface of this heretofore known covering 3~
exhibits varying ink transfer characteristics. Whereas the rounded corners of the glass beads again readily surrender to the sheet the ink which had been previously accepted and carried thereby, the troughs or valleys located between the glass beads and formed of adhesive material and rubber solvent tend to have ink build up therein. A consequence thereof is that such glass-bead cloths must be washed very often which causes the individual glass beads to loosen very easily from the adhesive connection thereof. In the long run, glass-bead cloths do not exhibit any satisfactory results with respect to preventing smearing. The heretofore known glass-bead clothes are useable, in any event, only limitedly on sheet delivery cylinders because, with the transition of the chain gripper from the circular path of the sprocket wheel to the straight path of the chain, a speed differing slightly from the peripheral or surface speed of the cylinder body of the sheet delivery cylinder is ~
imposed upon the sheet being transferred. ~he shifting of the freshly printed underside of the sheet relative to the covering, namely the glass-bead cloth, which results from the slight difference in speed, causes smearing of the printed image.
It is accordingly an object of the invention to provide, in a sheet transfer cylinder of a rotary printing machine, a cylinder body having a covering which is capable of being , L3~
produced by relatively simple means and relatively simply securable on the sur~ace o~ the cylinder body, the transfer-cylinder covering being effective for avoiding smearing and scratching of the wet printed image even when there is relative motion between the freshly printed underside of the sheet and the transfer-cylinder covering.
It is another object of the invention, to provide such a transfer-cylinder covering which will permit trouble-free printing of editions of at least 500,000 printings without any deterioration of the printed image becoming noticeable.
It is a further object of the invention to provide such a transfer-cylinder covering which can be cleaned in a relatively simple manner while it remains on the sheet transfer cylinder.
With the foregoing and other objects in view, there is provided, in accordance with the invention, a sheet transfer cylinder of a rotary printing machine having a cylinder body with a surface whereon means are provided for preventing smearing of a freshly printed underside of a sheet being transfered by the sheet transfer cylinder, the smear-preventing means comprising a covering applied to the cylinder body and formed of twill material having a rough sur~ace structure and being compressible due to a presence of air occlusions therein, with a warp thread count of substantially 24.7 to 50.4 per cm and a weft count of substantially 14~5 to 22.7 per cmO
Long lasting tests have produced the surprising evidence that it is sufficient to cover the peripheral or casing 3~
surface of a sheet ~ransfer cylinder or casing surface of a sheet transfer cylinder solely with a compressible textile material so as to be able to transfer freshly prin-ted sheets without smearing. Even with the use of this covering on sheet delivery cylinders during which relative motion inevitably occurs between the freshly printed sheet under-side and the covering of the cylinder, no scratching and no smearing of the printing image could be detected. What is especially surprising, is that these textile-type coverings retain the non-ink-smearing characteristics or the printing-image preserving transferability thereof over a great number of printing or over a large printing edition.
Various types of textile fabrics have been tested in order to determine those parameters or characteristics thereof which render them particularly suitable for the purpose of this invention.
Example A
The textile material which was found to be best suited as a cylinder covering for retaining the non-ink-smearing characteristics or the printing-image-preserving transfer-ability thereof over a great number of printings is a twill fabric having a warp thread count per cm of substantially 33.4 and a weft thread count per cm of substantially lg.0, a normal-condition warp fineness of substantially 47.4 tex or, as expressed in terms of yarn number substantially 21.1, f~ L~
and a weft fineness of substantially 48~1 tex or, also as expressed in terms of yarn number - substantially 20~8/
and warp liftings per cm of substantially 158~ 7 ~ Both the warp and the weft threads are formed of pure cotton. The 5 weight per unit surface area of this textile material is 293 g/m , the raw state density thereof is 0. 314 g/cm and the percentage by volume of the pores formed therein is 79 ~ 6 % ~
Twc other textile materials were found also te be well suited for the purposes of the inven-tion although not quite as.good as the just-mentioned textile material.
Example B
One of these other well suited textile materials is a twill fabric having a warp -thread count per cm of sub-stantially 50. 4 and a weft thread count per cm of sub-stantially 22~7r a normal-condition warp fineness of substantially 27~4 -tex or yarn number of substantiall.y 36~5 and a weft fineness of substantially 43 ~ 1 tex or yarn number of substantially 28~2~ and warp liftings per cm of 20 substantially 286~0~ Both the warp and the weft threads are also formed of pure cotton. The weigh-t per unit surface area of this textile material is 261 g/m , the raw s-tate density thereof is 0. 381 g/cm , and the percentage 24 by volume of the pores formed therein is 79 ~ 6~o ~
. .
3~
Example C
The second of the other two well suited materials is also a twill fabric which, however, has a warp thread count per cm of substantially 32.5 and a weft thread count per cm of substantially 19.4, a normal-condition warp fineness of substantially 47.3 tex or yarn number of substantially 21.1, and a weft fineness of substantially 64.1 tex or yarn number of substantially 15.6, and warp liftings per cm 2 of substantially 157.6. Both the warp and the weft threads are also formed of pure cotton. The weight per unit surface area of this textile materials is 315 g/m2, the raw state density thereof is 0.422 g/m2, and the percentage by volume of the pores formed therein is 72.6%.
Less suitable for the purposes of the invention and, indeed, critical though nevertheless usable there~ore are two textile fabrics respectively, exhibiting a great degree of profiling or a low working surface and a great extent of smoothness.
~ ~ '.
: ' The textile material having the greatest profiling o~ all the fabrics tested is also a twill fabric which, however, has a warp thread count of substantially 24.7 per cm and a weft thread count of substantially 15.0 per cm, a normal-condition warp fineness of substantially 94.8 tex or yarn number of 10.5 and a weft fineness of substantially 68.6 tex or yarn number of substan-3~3~
tially 14.6, and warp liftings of substan-tially 92.6 per cm2. The warp is formed oE pure cotton but the weft is formed of a mixture of polyester and co-tton. The weight per unit surface area of this textile ma-terial is 368 g/m2, the raw state density thereof is 0.335 g/c3, and the percentage by volume of the pores formed therein is 77.7%.
EXAMPLE E
_ The textile material exhibiting great smoothness i.e. limited profiling, is a cross-twill fabric and has a warp thread count of substantially 25.0 per cm and a weft thread count of substantially 14.5 per cm, a normal-condition warp fineness of substantially 87.7 tex or yarn number of substantially 11.4, and a we:Et fineness of substantilly 75.2 tex or yarn number of substantially 13.3, and warp liftings of substantially 90.6 per cm2. Both the weft and the warp threads are formed of pure cot-ton. The weight per unit surEace area of this textile material is 366 g/m2 the raw state density thereof is 0.352 g/cm3, and the percentage by volume of the pores formed therein is 77.1%.
Thus the textile fabrics of Example D and E are critical with respect to the efficient operation thereof for the purposes of the invention and have limiting characteristics at opposite ends of the range of characteristics manifested by the tested materials usable in accordance with the invention.
q~
Example F
A textile material which was found to have poor runability for the intended use in accordance with the invention is a linen fabric which has a warp thre^~--d^ count of substantially 16.2 cm and a weft thread coun-t of substant-ially 13.9 per cm and a weft thread count of substantially 8.6, and a weft fineness of substantially 122.2 tex or ~:
yarn number of substantially ~.2, and warp liftings of substantially 112.62. Both the weft threads and the warp threads are Eormed of pure wool. The weight per unit surface area of this textile material is 445 g/m2, ~, the raw state density thereof is 0.400 g/cm3, and the percentage by volume of the pores formed therein is 69.7~.
The textile material oE Example F has the smoothest surface of all of the foregoing textile materials tested.
Considering that fact and that the material of Example E also has a very smooth surface and is critical with respect to the runability thereof for the intended use, and further considering that the textile material of Example D has the roughest profiling of the surface structure thereof and is also critical with respect to the runability thereof for the intended use, it has become apparent that the profiling of the surface structure of the -textile fabric plays an important role in the selection of the fabric according to the inven-tion. Eabrics with a very smooth surface such as that of Example F, and fabrics with very strong or rough profiling and low working surface, accordingly, namely greater than that of Example D, are consequently not suited for attaining the objectives of the invention of the instant application.
Among the foregoing examplesof textile fabrics, that o Example B had the least thickness while that of Example F
was thickest. In compression tests administered to all of the fabrics, that of Example D had the greatest compressi-bility followed by Examples A, E, F, B and C of sequentially lower compressibility.
With respect to the parameter warp thread liftings per cm , it is noted that the respective value thereof is a function of the amount of thread per cm of warp and weft, as well as of the weave. Of the six fabrics of the examples, those of Example A, B, C and D are twill weave K - /S, that of Example E is cross-twill weave XK ~, and that of the undesirable Example F, linen weave L~
It ha~s been surprisingly found from the testing of the various textile materials that when the thread fineness of the optimally functioning textile fabrics of Examples A, B and C are exceeded or the thread count reduced, an additional parameter or characteristic of the textile fabric must be varied i.e. the weave cross-twill of Example E or the composi-tion of the -thread, namely the weft of polyester/cotton of Example D in order to attain at least reasonable functioning of such a textile material.
A dry rub-down is ordinarily sufficient for cleaning these textile-type coverings. Ink residues, which adhere to -the tipS of the textile or web par-ts projecting out of the supporting covering surface can accordingly be rubbed off with ease. At greater intervals, wet cleaning by conven-tional roller and form washing means is also possible.
Tests have established, however, that such wet cleaning of the textile-type covering is unnecessary under 1,000,000 printings.
In accordance with another feature of the invention, the covering is formed of a web of yarn, fleece material, tufted material or knitted fabric.
In accordance with a further feature of the invention, the covering is formed of a tightly woven textile material having, at least on one side thereof, a tufted and brushed surface, respectively.
From knowledge which has been gained, the operation of the invention of the instant application is based upon two mutually assisting operations. For one, the freshly printed underside of the sheet initially contacts a multiplicity of yielding supporting points of the rough surface structure of the textile material quite in contrast to'the glass-bead cloths wherein the supporting domes or prominences, in this regard, are non-yielding. For the other, during the further close approach of the sheet to the peripheral surface, an air cushion is inevitably formed due to the yieldabili-ty of the supporting points of the textile material, because the structure of the textile material impedes shifting of the air in every lateral direction. As the sheet approaches even more closely to the covering, an overpressure or excess pressure is produced, respectively, between the sheet and the peripheral surface of the cylinder body and between the sheet and the underside of the covering in the case where the latter is reinforced on one side thereof. It has been found that both this air cushion as well as the pro-truding textile parts, which are movable within given limits, carry the freshly printed underside of the sheet in a manner that a relative movement, such as inevitably occurs in a chain delivery system, cannot produce smearing and scratching of the printed image.
For better handling and in order to prevent the formation of folds when putting on a covering according to the invention, the side of the covering facing or lying on the cylinder body surface is reinforced.
In accordance with an additional feature of the invention, the covering is formed of brushed denim material. Even the 25 most del:Lcate printing could be fed without quality loss to ~
- 12 - `
' ~ ' ~ ' -3~
the sheet delivery stack by such a covering. Basically, however, all textile material i.e. any fiber-containing material whether ornot it has a linen, twill or satin cross-weave or is formed of a knit, can be used for the covering material. Likewise, tufted material is also able to be so used.
In accordance with yet another feature of the invention, burr-type closures are included at respective ends of the covering for readily releasably fastening the covering to the cylinder body.
In accordance with yet a further feature of the invention, the covering is readily releasably secured by adhesive to the surface of the cylinder body~
In accordance with yet an additional feature of the invention, the cylinder is a sheet delivery cylinder, and the covering is disposed on the surface of -the cylinder body of the sheet delivery cylinder.
In accordance with an added feature of the invention, -the covering is formed of a twill fabric.
In accordance with another feature of the invention, the fabric has a warp thread count of from substantially 24.7 to substantially 50.4 per cm and a weft thread count of from substantially 14.5 to subs-tantially 22.7 per cm.
In accordance with a further feature of the invention, the warp of the fabric has a normal condition fineness ranging from substantially 27.~ tex to substantially 94.8 tex and the weft of the fabric from substantially 43.1 tex to substantially 75.2 tex.
In accordance with yet another fea-ture of the invention, the fabric has warp thread liftings per cm ranging from substantially 90.6 to substantially 286Ø
In accordance with yet a further feature of the invention, the fabric has a cross-twill weave having a warp thread count of substantially 25.0 and a weft thread count of substantially 14.5 per cm, a normal condition warp fineness of substantially 87.7 tex and weEt fineness of substantially 75.2 tex, and warp liftlngs per cm of substantially 90.6.
In accordance with yet an additional feature of the invention, the fabric has a warp thread count of substantially 24.7 and a weft thread count of substantially 15.0 per cm, a normal condition warp fineness of substantially 94.8 tex and weft fineness of substantially 68.6 tex, and warp liftings per cm of substantially 92.6.
In accordance with yet an added feature of the invention, the fabric has a warp thread count of substantially 50.4 and a weft :thread count of substantially 22.7 per cm, a normal-condition warp fineness of substantially 27.4 tex and weft fineness of substantially 43.1 tex, and warp liftings per cm of substantially 286Ø
In accordance with an alternate feature of the invention, the fabric has a warp thread count per cm of substantially 33.4 and a weEt thread count per cm of substantially 19.0, a normal-condition warp fineness of substantially 47.4 tex and weft fineness of substantially 48.1 tex, and warp liftings per cm of substantially 158.7.
In accordance with still a further feature of the invention, the fabric has a warp thread count per cm of substantially 32.5 and a weft thread count per cm of substantially 19.4, a normal-condition warp fineness of substantially 47.3 tex and weft fineness of substantially 64.1 tex, and warp liftings per cm of substantially 157.6.
In accordance with again another feature of the invention, the fabric is formed with pores having a precent by volume 15 ranging from substantially 72.6 to substantially 79.6.
In accordance with again a further :Eeature oE the invention, the fabric has a weight per unit surface area ranging from substantially 261 to substantially 368 g/m .
~ In accordance with again an alternate feature of the ; 20 invention, the warp is of pure cotton and the weft is either of pure cotton or of a mixture of polyester and cotton.
In accordance with a concomitant feature of the invention, the rotary printing machine has a sheet transfer cylinder disposed between respective printing units for transfering printed sheets from one unit to the other, the sheet transEer ~f~
cylinder comprising a cylinder body, and a smear-preventing covering applied to the cylindrical surface of the body, the covering being formed of textile material having rough surface structure and being compressible due to a presence of air occlusions therein.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a sheet transfer cylinder in rotary printing machines, it is nevertheless not intended to be limi-ted to the details shown, since various moclifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:
FIG. 1 is a diagrammatic side elevational view of a chain delivery system;
FIG 2 is an enlarged fragmentary view, partly in section, of FIG 1 showing a sheet delivery cylinder on the chain sprocket wheel shaft, a covering according to the invention being shown carried by the cylinder body of the sheet delivery cylinderi FIG. 3 is an even further enlarged fragmentary view of FIG. 2 showing the covering of the sheet delivery cylinder in greater detail;
FIG. 4 is another enlarged fragmentary view of FIG. 2 showing the means of fastening the covering to the cylinder body of the sheet delivery cylinder; and FIG. 5 is a diagrammatic side elevational view, partly in section, of sheet transfer cylinders with coverings accord- :
ing to the invention, the transfer cylinders being disposed between printing units of a rotary printing machine.
Reffering now to the drawing and first, particularly, to FIG. 1 thereof, there is shown an impression cylinder 1 of the last printing uni-t of a multicolor sheet-fed rotary offset printin~ machine which trans~ersa printed sheet 2 to a gripper bridge 3 of a chain delivery 4. In t~is regara, a sheet delivery cylinder 6 provided on the sprocket- -wheel shaft 6 disposed closer to the impression cylinder 1 advances the sheet 2 with the freshly printed side thereof facing the sheet delivery cylinder 5, during the transfer operation. The gripper bridges 3 transfer the surrendered sheet 2 to the sheet delivery stack 7.
As shown in FIG. 2, -the peripheral or shell surface 8 of the sheet delivery cylinder 5 is covered with a covering 9, which is formed of textile material having a rough surface a~
structure and provided with air occlusions rendering the textile material compressible. This textile material can be produced as a web of yarn, a reinforced or stiffened fleece material, a tufted material or a knitted fabric.
In the embodiment of the invention specifically described herein and illustrated in the drawing r the covering is formed of brushed denim material.
FIG. 3 is illustrative of the mode of operation of a covering according to the invention. Upon the surrender of the sheet 2 by the impression cylinder 1 to the sheet del~very cylinder 5, the textile-type covering 9 is sli~htly compressed due to the stress in the sheet 2. This occurs, among other reasons, due to the fact that the sheet 2 remains adhered to the non-illustrated blanket cylinder of the last printing unit and must be withdrawn from the surface thereof : by the use of a given force. The hugging or close approach of the sheet 2 gripped by the gripper bridges 3 to the covering 9 works in two ways. First, the freshly printed shee-t underside hugs or makes close contact with the yielding supporting parts of the rough surface structure of the covering material. Then, due to the hereinafore mentioned stress in the sheet 2, a compression or pressing-in of these yielding supporting parts of the surface structure of the covering 9 is effected. Since the web or texture of the covering 9 impedes lateral escape of the air, an air cushion with excess pressure or overpressure is formed. Both the yielding raised web parts and the air cushion together support the sheet 2 guided by the gripper bridges 3 at the freshly printed side of the sheet 2. The instant that the gripper bridges 3 holding the end of the sheet 2 then leave the circular path about the sheet delivery cylinder 5 and run into the straight chain path of the chain delivery 4, the speed thereof diminishes slightly. A consequence thereof is that the sheet 2 transfered by the sheet delivery cylinder 5 performs a slight movement relative to the peripheral or outer cylindrical surface of the sheet delivery cylinder 5.
Notwithstanding this relative motion, no scratching or smearing of the printing image is effected. The textile-type covering ~ is able to be fastened to the side walls 10 defining -the channel or slot 11 of the sheet delivery cylinder 5 in a relatively simple manner by means of burr-like closures or fasteners 12 shown in FIG. ~. The latter are formed, on the one side, of an adhesive foil provided with hooks and, on the other side, of an adhesive foil studded with eyes.
One of these adhesive foils is fastened to the textile covering 9, the other to the wall 10 of the cylinder channel 11. Merely by pressing the one part of the burr-like fastener or closure 12 to the other part thereof, the covering 9 is tightly clamped. The burr-like closure 12 thus permits clamping and removal of the covering 9 in a relatively simple manner by hand i.e. without the aid of tools.
The fastening of the ends of the covering 9 by means of burr-like closures can also be effected at other parts of the wall of the sheet delivery cylinder 5 as, indeed, at the side walls 10 defining the channel 11. Li.kewise, the possibility exists of providing a burr-like closure part on the sheet delivery cylinder 5, the te~tile-type covering 9 adhering directly thereto.
The use of the covering 9 in accordance with the invention is ; not limited to the sheet delivery cy:Linder. On the contrary, such covering 9, as shown in FIG. 5, can find utility also in sheet transfer cylinders.
In the illus-trated embodimen-t of FIG.. 5, a s-torage cylinder 15 surrenders the previously printed sheet 2 to a sheet -transfer cylinder 16. Since the latter must transfer the sheet 2 with the printed side ihereof facing it, a textile-type covering 9 in accordance with the invention is provided thereon. The impression cylinder 17 takes over the sheet
2 from the sheet transfer cylinder 16 and guides it through the printing nip or gap 18 which is formed between the blanket cylinder 19 and the impression cylinder 17. After again being printed, the sheet 2 is taken over by another sheet transfer cylinder 20, the freshly printed sheet side, likewise, ~:
25 coming to lie on the peripheral or outer cylindrical surface ~:
25 coming to lie on the peripheral or outer cylindrical surface ~:
3~
of the cylinder 20. The latter is -therefore, likewise, provided with a covering 9 according to the invention.
The sheet 2 is passed on by the sheet transfer cylinder 20 to the storage cylinder 21. Since the storage cylinder 21 transfers the shee-t 2 with the unprinted side thereof facing it, the storage cylinder 21 re~uires no covering 9 according to the invention, which means that.we are dealing with a perfector printing machine. Textile-type coverings accord-ing to the invention, because of the smear-free transfer 10 thereby of printed sheets, the low manufacturing costs thereof .
and the relatively simple means of mounting or clamping thereof on the transfer cylinders as well as of cleaning thereof, can bc installed or introduced with great advantage on all sheet transfer cylinders. Another special advantage, moreover, is that the covering may begin directly in vlcinity of the printing commencement, which is not achievable with all heretofore known types of sheet transfer cylinders.
The invention of the ins-tant application is not necessarily limited to natural textile material. Of course, the inventive effect may be attained also with textile materials of plastics or synthetics, such as roughened imitation leather as well as also natural leather, the surface of which is made fibrous. The scope of the invention encompasses all coveringsof sheet transfer cylinders, the surface structure of which has yielding supporting parts, and which sufficiently impedes lateral escape or spread of air out of the region of the supporting web parts.
of the cylinder 20. The latter is -therefore, likewise, provided with a covering 9 according to the invention.
The sheet 2 is passed on by the sheet transfer cylinder 20 to the storage cylinder 21. Since the storage cylinder 21 transfers the shee-t 2 with the unprinted side thereof facing it, the storage cylinder 21 re~uires no covering 9 according to the invention, which means that.we are dealing with a perfector printing machine. Textile-type coverings accord-ing to the invention, because of the smear-free transfer 10 thereby of printed sheets, the low manufacturing costs thereof .
and the relatively simple means of mounting or clamping thereof on the transfer cylinders as well as of cleaning thereof, can bc installed or introduced with great advantage on all sheet transfer cylinders. Another special advantage, moreover, is that the covering may begin directly in vlcinity of the printing commencement, which is not achievable with all heretofore known types of sheet transfer cylinders.
The invention of the ins-tant application is not necessarily limited to natural textile material. Of course, the inventive effect may be attained also with textile materials of plastics or synthetics, such as roughened imitation leather as well as also natural leather, the surface of which is made fibrous. The scope of the invention encompasses all coveringsof sheet transfer cylinders, the surface structure of which has yielding supporting parts, and which sufficiently impedes lateral escape or spread of air out of the region of the supporting web parts.
Claims (11)
OR PRIVILEDGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. In a sheet transfer cylinder of a rotary printing machine having a cylinder body with a surface having means thereon for preventing smearing of a freshly printed underside of a sheet being transferred by the sheet transfer cylinder, the improvement wherein the smear-preventing means comprise a covering applied to the cylinder body and formed a twill fabric having a rough surface structure and being compressible due to a presence of air occlusions therein, said fabric having warp threads and weft threads wherein the fabric has a warp thread count of from substantially 24.7 to substantially 50.4 per cm and a weft thread count of from substantially 14.5 to substantially 22.7 per cm.
2. Sheet transfer cylinder according to Claim 1, wherein the warp of the fabric has a normal condition fineness ranging from substantially 27.4 tex to substantially 94.8 tex and the weft of the fabric from substantially 43.1 tex to substantially 75.2 tex.
3. Sheet transfer cylinder according to Claim 1, wherein the fabric has warp thread liftings per cm2 ranging from substantially 90.6 to substantially 286Ø
4. Sheet transfer cylinder according to Claim 1, wherein the fabric has a cross-twill weave having a warp thread count of substantially 25.0 and a weft thread count of substantially 14.5 per cm, a normal-condition warp fineness of substantially 87.7 tex and weft fineness of substantially 75.2 tex, and warp liftings per cm of substantially 90.6.
5. Sheet transfer cylinder according to Claim 1, wherein the fabric has a warp thread count of substantially 24.7 and a weft thread count of substantially 15.0 per cm, a normal-condition warp fineness of substantially 94.8 tex and weft fineness of substantially 68.6 tex, and warp liftings per cm2 of substantially 92.6.
6. Sheet transfer cylinder according to Claim 1, wherein the fabric has a warp thread count of substantially 50.4 and a weft thread count of substantially 22.7 per cm, a normal-condition warp fineness of substantially 27.4 tex and weft fineness of substantially 43 .1 tex, and warp liftings per cm2 of substantially 286Ø
7. Sheet transfer cylinder according to Claim 1, wherein the fabric has a warp thread count per cm of substantially 33.4 and a weft thread count per cm of substantially 19.0, a normal-condition warp fineness of substantially 47.4 tex and weft fineness of substantially 48.1 tex, and warp liftings per cm2 of substantially 158.7.
8. Sheet transfer cylinder according to Claim 1, wherein the fabric has a warp thread count per cm of substantially 32.5 and a weft thread count per cm of substantially 19.4, a normal-condition warp fineness of substantially 47.3 tex and weft fineness of substantially 64.1 tex, and warp liftings per cm2 of substantially 157.6.
9. Sheet transfer cylinder according to Claim 1, wherein the fabric is formmed with pores having a percent by volume ranging from substantially 72.6 to substantially 79.6.
10. Sheet transfer cylinder according to Claim 1, wherein the fabric has a weight per unit surface area ranging from substantially 261 to substantially 268 g/m2.
11. Sheet transfer cylinder according to Claim 1, wherein the warp is of pure cotton and the weft is either of pure cotton or of a mixture of polyester and cotton.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US13544680A | 1980-03-31 | 1980-03-31 | |
| US135,446 | 1980-03-31 | ||
| US21511780A | 1980-12-10 | 1980-12-10 | |
| US215,117 | 1980-12-10 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1154304A true CA1154304A (en) | 1983-09-27 |
Family
ID=26833327
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000371341A Expired CA1154304A (en) | 1980-03-31 | 1981-02-20 | Sheet transfer cylinder in rotary printing machines |
Country Status (11)
| Country | Link |
|---|---|
| EP (1) | EP0036937B1 (en) |
| JP (1) | JPS56151565A (en) |
| AU (1) | AU538331B2 (en) |
| BE (1) | BE887975A (en) |
| BR (1) | BR8101843A (en) |
| CA (1) | CA1154304A (en) |
| DE (2) | DE3105683C2 (en) |
| DK (1) | DK40181A (en) |
| ES (1) | ES267117Y (en) |
| IT (1) | IT1135456B (en) |
| NO (1) | NO811087L (en) |
Families Citing this family (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4402267A (en) * | 1981-03-11 | 1983-09-06 | Printing Research Corporation | Method and apparatus for handling printed sheet material |
| DE3347886A1 (en) * | 1983-08-06 | 1985-05-30 | Heidelberger Druckmaschinen Ag, 6900 Heidelberg | Smear-free transfer drum for sheet-fed rotary printing machines |
| DE3328451A1 (en) | 1983-08-06 | 1985-02-21 | Heidelberger Druckmaschinen Ag, 6900 Heidelberg | LUBRICATION-FREE REPLACEMENT DRUM FOR ARC TOTAL PRINTING MACHINES |
| DE3507925A1 (en) * | 1985-03-06 | 1986-09-11 | M.A.N.- Roland Druckmaschinen AG, 6050 Offenbach | BOW TRANSPORT DRUM FOR ROTARY PRINTING MACHINES |
| US4691632A (en) * | 1986-07-08 | 1987-09-08 | Demoore Howard W | Method and apparatus for attaching anti-smear net to printing press transfer cylinder |
| JPS6323035U (en) * | 1986-07-30 | 1988-02-16 | ||
| US5042384A (en) * | 1990-04-30 | 1991-08-27 | Howard W. DeMoore | Anti-marking method and apparatus for use with perfector cylinders of rotary sheet-fed printing presses |
| DE4204254C2 (en) * | 1992-02-13 | 1995-03-16 | Koenig & Bauer Ag | Device for longitudinal folding of several paper webs of the same width in a web-fed rotary printing press |
| US5415098A (en) * | 1994-01-18 | 1995-05-16 | Ward; Donald A. | Method and apparatus for handling sheet material using ridged netting |
| DE4436583A1 (en) * | 1994-10-13 | 1996-04-18 | Heidelberger Druckmasch Ag | Quality control appts. for paper sheets in rotary printing machine |
| US5907998A (en) * | 1995-12-29 | 1999-06-01 | Howard W. Demoore | Anti-static, anti-smearing pre-stretched and pressed flat, precision-cut striped flexible coverings for transfer cylinders |
| US5979322A (en) * | 1996-05-07 | 1999-11-09 | Demoore; Howard Warren | Environmentally safe, ink repellent, anti-marking flexible jacket covering having alignment stripes, centering marks and pre-fabricated reinforcement strips for attachment onto transfer cylinders in a printing press |
| US5842412A (en) * | 1997-03-07 | 1998-12-01 | Bba Nonwovens Simpsonville, Inc. | Anti-marking covering for printing press transfer cylinder |
| DE19745763A1 (en) * | 1997-10-16 | 1999-04-22 | Heidelberger Druckmasch Ag | Transport drum in rotary printing machines |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3126826A (en) * | 1964-03-31 | Transfer cylinder for rotary multi-color printing presses | ||
| US1336995A (en) * | 1919-07-31 | 1920-04-13 | Allen B Beck | Device for preventing offset in printing-presses |
| US3308522A (en) * | 1962-12-14 | 1967-03-14 | Velcro Corp | Anti-offset roll |
| AT341550B (en) * | 1975-05-10 | 1978-02-10 | Heidelberger Druckmasch Ag | ARC FEED DRUM FOR PRINTING MACHINES |
| GB1505623A (en) * | 1975-07-11 | 1978-03-30 | Heidelberger Druckmasch Ag | Transfer drum and drum blanket for sheet-fed rotary printing presses |
-
1981
- 1981-01-29 DK DK40181A patent/DK40181A/en not_active Application Discontinuation
- 1981-02-13 IT IT19719/81A patent/IT1135456B/en active
- 1981-02-17 DE DE3105683A patent/DE3105683C2/en not_active Expired
- 1981-02-17 DE DE8181101102T patent/DE3163807D1/en not_active Expired
- 1981-02-17 EP EP81101102A patent/EP0036937B1/en not_active Expired
- 1981-02-20 CA CA000371341A patent/CA1154304A/en not_active Expired
- 1981-02-27 AU AU67937/81A patent/AU538331B2/en not_active Ceased
- 1981-03-16 BE BE0/204146A patent/BE887975A/en not_active IP Right Cessation
- 1981-03-18 ES ES1981267117U patent/ES267117Y/en not_active Expired
- 1981-03-27 BR BR8101843A patent/BR8101843A/en unknown
- 1981-03-30 NO NO811087A patent/NO811087L/en unknown
- 1981-03-31 JP JP4656481A patent/JPS56151565A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| DK40181A (en) | 1981-10-01 |
| JPS56151565A (en) | 1981-11-24 |
| DE3163807D1 (en) | 1984-07-05 |
| BR8101843A (en) | 1981-10-06 |
| ES267117U (en) | 1983-02-16 |
| IT8119719A0 (en) | 1981-02-13 |
| NO811087L (en) | 1981-11-30 |
| EP0036937A1 (en) | 1981-10-07 |
| IT1135456B (en) | 1986-08-20 |
| AU538331B2 (en) | 1984-08-09 |
| DE3105683C2 (en) | 1985-03-28 |
| DE3105683A1 (en) | 1982-03-04 |
| ES267117Y (en) | 1983-08-16 |
| AU6793781A (en) | 1981-10-08 |
| BE887975A (en) | 1981-07-16 |
| EP0036937B1 (en) | 1984-05-30 |
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