U.S. patent application number 10/764635 was filed with the patent office on 2004-08-12 for folding roll for a folding apparatus and methods for its production.
This patent application is currently assigned to MAN Roland Druckmaschinen AG. Invention is credited to Echerer, Siegmund, Schmid, Martin.
Application Number | 20040157716 10/764635 |
Document ID | / |
Family ID | 32667993 |
Filed Date | 2004-08-12 |
United States Patent
Application |
20040157716 |
Kind Code |
A1 |
Echerer, Siegmund ; et
al. |
August 12, 2004 |
Folding roll for a folding apparatus and methods for its
production
Abstract
A folding roll distinguished by good shape and dimensional
accuracy bears a frictional layer applied to the even surface of
the folding roll, adjacent deeper areas being formed by
application-free regions. The method of producing the folding roll
includes the fitting of a mask to the folding roll, the mask having
cutouts with the form of frictional areas to be applied. This is
followed by the application of the frictional layer by means of
thermal spray-coating and, following that, the removal of the
mask.
Inventors: |
Echerer, Siegmund;
(Neukirchen, DE) ; Schmid, Martin; (Hirblingen,
DE) |
Correspondence
Address: |
COHEN, PONTANI, LIEBERMAN & PAVANE
551 FIFTH AVENUE
SUITE 1210
NEW YORK
NY
10176
US
|
Assignee: |
MAN Roland Druckmaschinen
AG
|
Family ID: |
32667993 |
Appl. No.: |
10/764635 |
Filed: |
January 26, 2004 |
Current U.S.
Class: |
492/30 |
Current CPC
Class: |
B65H 2404/182 20130101;
B65H 45/18 20130101; C23C 4/185 20130101; B65H 45/221 20130101;
B65H 2404/522 20130101 |
Class at
Publication: |
492/030 |
International
Class: |
B21B 001/40 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 4, 2003 |
DE |
103 04 534.1 |
Claims
What is claimed is:
1. A folding roll for a folding apparatus, said folding roll
comprising: at least one cylindrical surface having at least one
frictional area to which frictional material has been applied by
thermal spray coating, said at least one frictional area being
bounded by deeper areas to which no friction material has been
applied.
2. A folding roll as in claim 1 wherein said at least one
frictional area comprises a plurality of four-corned frictional
areas.
3. A folding roll as in claim 1 wherein said at least one
frictional area comprises a strip of frictional material running
spirally around said cylindrical surface.
4. A folding roll as in claim 1 wherein said at least one
cylindrical surface comprises a plurality of cylindrical surfaces
separated by circumferential channels for tape lines, each said
circumferential channel having a circumferential surface provided
with at least one frictional area to which frictional material has
been applied by thermal spray coating.
5. A folding roll as in claim 1 wherein said frictional material
has a depth of about 0.3 mm on said frictional areas.
6. A folding roll as in claim 2 wherein said folding roll comprises
part of a third longitudinal folding apparatus.
7. A folding roll as in claim 3 wherein said folding roll comprises
part of a folding former.
8. A method of producing a folding roll for a folding apparatus,
the method comprising: fitting a mask to at least one cylindrical
surface, said mask having cutouts shaped and arranged to correspond
to the shape and arrangement of desired frictional areas on said at
least one cylindrical surface; applying a frictional material by
means of thermal spray-coating to said mask and said at least one
cylindrical surface via said cutouts; and removing said mask.
9. A method as in claim 8 wherein said mask is provided with
longitudinal edges, said mask being fitted to said at least one
cylindrical surface so that said longitudinal edges form a butt
joint.
10. A method of producing a folding roll for a folding apparatus,
the method comprising: winding a strip-like mask around a
cylindrical surface spirally to form turns separated by a gap
corresponding to a frictional area extending spirally around said
cylindrical surface; applying a frictional material by means of
thermal spray-coating to said mask and said at least one
cylindrical surface via said gap; and removing said mask.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to a folding roll for a folding
apparatus, which bears a frictional layer applied by means of
thermal spray coating, and methods for producing the folding
roll.
[0003] 2. Description of the Related Art
[0004] Folding rolls are known in which carrying portions have been
produced on the circumferential surface by means of
material-removing methods and a ceramic layer has subsequently been
applied by means of thermal spray coating.
[0005] The production of such folding rolls is time-consuming and
expensive. In addition, only coarse fabrication tolerances can be
achieved. Furthermore, irregularities occur on the profile of the
frictional layer and, on the edges of the profile, the formation of
burrs is to be noted, which can cause damage to the folded
product.
SUMMARY OF THE INVENTION
[0006] It is an object of the invention to provide a folding roll
which is distinguished by good shape and dimensional accuracy. In
addition, a method for the inexpensive production of a folding roll
is to be provided.
[0007] According to the invention, the object of providing a
folding roll is achieved by applying a frictional material only to
frictional areas on the even surface of the folding roll, thereby
forming a frictional layer which is interrupted by deeper areas
where the material has not been applied. The folding roll can be
produced with little expenditure on time and costs. In addition,
close fabrication tolerances can be maintained. The profile
produced is also very uniform and can be produced without burrs
which damage the folded product.
[0008] According to a preferred method, a sheet-metal mask having
cut-outs with the shape of the desired frictional areas is fitted
to the folding roll, the frictional layer is applied to the folding
roll through the cut-outs by means of thermal spray coating, and
the mask is removed. According to another method, a mask is wound
spirally onto the circumferential surface of the folding roll, the
frictional layer is applied to the areas not covered by the mask by
means of thermal spray coating, and the mask is removed. By using a
mask, the provision of carrying portions of the surface by means of
specific production methods is rendered superfluous. The mask can
be applied to the roll and removed from the latter with little
expenditure on time and can be used many times. In addition, the
frictional layer profiles can be produced more uniformly and
without forming burrs, which improves the function of the folding
roll. Moreover, the folding rolls produced in accordance with the
invention are distinguished by longer service lives and can be
conditioned again by grinding off and re-coating, which is likewise
reflected in lower costs. Further features and advantages emerge
from the subclaims in conjunction with the description.
[0009] Other objects and features of the present invention will
become apparent from the following detailed description considered
in conjunction with the accompanying drawings. It is to be
understood, however, that the drawings are designed solely for
purposes of illustration and not as a definition of the limits of
the invention, for which reference should be made to the appended
claims. It should be further understood that the drawings are not
necessarily drawn to scale and that, unless otherwise indicated,
they are merely intended to conceptually illustrate the structures
and procedures described herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 shows a folding roll;
[0011] FIG. 1 A shows the associated mask used to apply the
frictional layer;
[0012] FIG. 2 shows the detail 11 according to FIG. 1;
[0013] FIG. 3 shows a further variant of a folding roll;
[0014] FIG. 4 shows folding rolls in a third longitudinal folding
apparatus; and
[0015] FIG. 5 shows folding rolls on a folding former.
DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS
[0016] FIG. 1 shows a folding roll 1 with circumferential surfaces
F1 to F5, which are provided with a frictional layer 2. The
frictional layer has the surface structure shown in FIG. 2. It
comprises four-cornered frictional areas 3 which are bounded by
deeper areas 4. In the exemplary embodiment, the four-cornered
frictional areas 3 have a shape like a rhombus with about 8 and 16
mm spacing from the opposite corners. The deeper areas 4 are
designed in the manner of parallel grooves with a width of, for
example, 2 mm. The frictional area 3 can also have another surface
structure, for example the form of triangles or rectangles.
[0017] The frictional layer 2 is applied by thermal spray-coating.
For this purpose, first of all the mask 5 illustrated in FIG. 1A is
fitted to the folding roll 1, that is to say wound on. The mask 5
has a width B dimensioned such that its ends 6, 7 meet each other
and form a butt joint. The mask 5 wound on in this way is fixed by
means of clips, not illustrated. Other fixings are also possible,
for example by means of easily detachable spotting-on (spot
welding).
[0018] The mask 5 has a thickness of 1 mm, for example, and has
cutouts 8, of which the dimensions and the arrangement in relation
to one another equate to the shape and the arrangement of the
frictional areas 3. The cutouts 8 and the cutouts 9 also mentioned
further below are advantageously cut with a laser beam. The mask 5
is fitted to the folding roll 1 and aligned axially in such a way
that the cutouts 8 come to lie on the circumferential areas F1 to
F5 to be provided with the frictional areas 3. The mask is shown in
this axial alignment with the folding roll 1. The circumferential
surfaces F1 to F5 to be coated have an even surface. "Even" is
understood to mean that these surfaces have been produced
completely by normal surface treatment, for example by turning or
grinding, and that special carrying portions have not been
produced, for example by milling or chasing.
[0019] The frictional layer 2 is then applied to the folding roll 1
prepared in this way, first of all the roll surface advantageously
being sand-blasted at the points intended for the layer
application, which can therefore advantageously be carried out with
the mask 5 clamped on. Next, an adhesive base is applied and then
the frictional layer 2 is applied by means of thermal
spray-coating, beneficially by means of flame-spraying. Carbidic,
self-flowing alloys and mixtures are advantageously applied. For
example, use can be made of the spray powder offered by one
manufacturer under the company designation Metco 34F. The layer is
not intended to be remelted, in order that the tips of the granular
spray powder are not rounded by melting, and the frictional layer
has a high coefficient of friction. In the case of folding rolls, a
high coefficient of friction is aimed at for the working surface,
the frictional layer here, in order that the product to be folded
can be drawn reliably into the inlet gap. The spray powder
advantageously contains tungsten carbide. A metal layer is
advantageously applied as the frictional layer 2 by means of the
thermal spray-coating. However, an oxide-ceramic or metal-ceramic
layer can also be applied. Further principles of thermal
spray-coating are familiar to those skilled in the art, exemplified
by U.S. Pat. No. 5,644,828. The frictional layer 2 is applied, for
example, with approximately a thickness t=0.3 mm and, for example,
has a maximum roughness R.sub.max.ltoreq.0.2 mm.
[0020] The mask 5 also has rectangular cutouts 9 which come to lie
above grooves 10 in the folding roll 1, in which tape lines 11 (see
FIG. 4) run during folding operation. During the flame-spraying,
rectangular frictional areas 12 shaped in accordance with the
cutouts 9 are produced on the circumferential surfaces of the
grooves 10. For reasons of simplicity, only one rectangular
frictional area 12 is illustrated.
[0021] After the thermal spray-coating has been carried out, the
mask 5 is taken off the folding roll 1, to which the four-cornered
frictional areas 3 and rectangular frictional areas 12 are then
applied. Between them there are deeper areas, which are formed by
application-free regions which originate from the regions covered
by the mask 5. The folding roll 2 produced in the manner described
is advantageously used in third longitudinal folding apparatuses,
as shown in FIG. 4. In this third longitudinal folding apparatus
13, two folding rolls 1 operate together. A sheet 15 to be folded
is inserted into their inlet gap by means of a folding blade 14.
The tape lines 11 run in the grooves 10 in the folding rolls 1.
These are driven by friction on the frictional areas 12. The
folding roll 1 can also be used on buckle folding apparatuses, the
tape lines 11 and grooves 10 being superfluous.
[0022] The folding rolls 1 used in the third longitudinal folding
apparatus 13, as shown in FIG. 4, can also be provided with the
frictional areas 3 over only one circumferential region. A mask 5
which is used in this case and which has cutouts 8 accordingly
extending over only part of the width B can be fitted to the
folding roll 1 with its ends 6, 7 overlapping.
[0023] FIG. 3 shows a further variant of a folding roll 16, in
which a frictional layer 2 is formed by a strip 18 running around
spirally on the circumference 17 of the folding roll 16. For the
production of this strip 18, a mask 19 is wound spirally onto the
circumferential surface of the folding roll 16 to be coated,
leaving the strip region to be coated free. In FIG. 3, the winding
operation is shown schematically on the folding roll 16, which is
shown in part. The ends of the mask 19 are fixed to the
circumference 17 by means of a clip or in another way, for example
by means of spot-welding. As described in the previous exemplary
embodiment, the frictional layer is then applied to the folding
roll 16 together with the mask 19 by means of thermal
spray-coating, if appropriate following previous sand-blasting.
Then, the mask 17 is removed, whereupon the frictional layer is
constituted in the form of the strip 18 running around spirally.
The strip 18 is shown schematically on a subregion of the
circumference 17 of the folding roll 16. For the mask 19, use is
made of a sheet-metal strip 1 mm thick, for example. The frictional
layer, that is to say the strip 18, is advantageously again
implemented with a thickness of about 0.3 mm. The flame-spraying is
carried out as described in the previous exemplary embodiment, for
which reason repeated explanations are superfluous. The strip 18
has, for example, a width b of about 10 mm. It is also possible to
apply to the folding roll 16 a strip which consists of a sequence
of individual rectangular areas. In this case, the mask contains
corresponding windows 21, which are also shown by dash-dotted lines
as a design variant. In this case, too, the strip 19 is wound on
without an interspace b (therefore b=0).
[0024] The folding roll 16 is advantageously used on a folding
former 22, as shown in FIG. 5. Here, two folding rolls 16 operate
together. A web 23 folded longitudinally by the folding former 22
is fed into their inlet gap.
[0025] Thus, while there have shown and described and pointed out
fundamental novel features of the invention as applied to a
preferred embodiment thereof, it will be understood that various
omissions and substitutions and changes in the form and details of
the devices illustrated, and in their operation, may be made by
those skilled in the art without departing from the spirit of the
invention. For example, it is expressly intended that all
combinations of those elements and/or method steps which perform
substantially the same function in substantially the same way to
achieve the same results are within the scope of the invention.
Moreover, it should be recognized that structures and/or elements
and/or method steps shown and/or described in connection with any
disclosed form or embodiment of the invention may be incorporated
in any other disclosed or described or suggested form or embodiment
as a general matter of design choice. It is the intention,
therefore, to be limited only as indicated by the scope of the
claims appended hereto.
* * * * *