U.S. patent application number 17/057734 was filed with the patent office on 2021-07-08 for producing a product made of a flexibly rolled strip material.
The applicant listed for this patent is Muhr und Bender KG. Invention is credited to Andreas Barchet, Christian Bruser, Thomas Dahl, Alexander Eick, Joachim Ivo.
Application Number | 20210205872 17/057734 |
Document ID | / |
Family ID | 1000005488955 |
Filed Date | 2021-07-08 |
United States Patent
Application |
20210205872 |
Kind Code |
A1 |
Ivo; Joachim ; et
al. |
July 8, 2021 |
PRODUCING A PRODUCT MADE OF A FLEXIBLY ROLLED STRIP MATERIAL
Abstract
Producing a product from flexibly rolled metallic strip material
comprises feeding a flexibly rolled strip material; determining a
measured thickness profile of the strip material over the length of
the strip material and calculating a desired cutting position for a
blank to be produced from the strip material; separating a blank
from the strip material in the desired cutting position; rotating
the blank depending on the determined measured thickness profile
such that the blank is aligned with its thickness profile in a
defined processing position which differs from the desired cutting
position; processing the blank in the processing position by a
processing unit, wherein the blank is processed to form a
product.
Inventors: |
Ivo; Joachim; (Lennestadt,
DE) ; Dahl; Thomas; (Attendorn, DE) ; Barchet;
Andreas; (Lennestadt, DE) ; Bruser; Christian;
(Olpe, DE) ; Eick; Alexander; (Plettenberg,
DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Muhr und Bender KG |
Attendorn |
|
DE |
|
|
Family ID: |
1000005488955 |
Appl. No.: |
17/057734 |
Filed: |
May 6, 2019 |
PCT Filed: |
May 6, 2019 |
PCT NO: |
PCT/EP2019/061598 |
371 Date: |
November 23, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B21B 2015/0014 20130101;
B21B 15/0007 20130101; B21D 43/287 20130101; B21D 43/003
20130101 |
International
Class: |
B21D 43/00 20060101
B21D043/00; B21B 15/00 20060101 B21B015/00 |
Foreign Application Data
Date |
Code |
Application Number |
May 24, 2018 |
EP |
18174010.1 |
Claims
1-15. (canceled)
16. A method of producing a product from flexibly rolled strip
material, comprising: providing a flexibly rolled strip material of
a metallic material having a thickness profile with a variable
thickness over a length of the strip material; determining a
measured thickness profile of the strip material over the length of
the strip material and calculating a desired cutting position for a
raw blank to be produced from the strip material depending on the
determined measured thickness profile of the strip material and a
respective desired thickness profile of the blank to be cut
therefrom, and feeding the strip material to the desired cutting
position; cutting a raw blank from the strip material in the
desired cutting position, the raw blank being arranged in a cut-off
position after cutting; rotating the raw blank depending on the
determined measured thickness profile such that the raw blank is
positioned with its thickness profile in a defined processing
position that is different from the cut-off position; and
processing the raw blank in the processing position by a processing
device, wherein the raw blank is processed into a product.
17. The method according to claim 16, wherein the strip material
has a first strip region with a first thickness profile and an
adjoining second strip region with a second thickness profile over
the length, wherein the first thickness profile and the second
thickness profile differ from each another in the strip material,
wherein a first raw blank is separated from the first strip region
and a second raw blank is separated from the strip material from
the second strip region, and wherein the first raw blank and the
second raw blank are rotated such that the first thickness profile
and the second thickness profile are equally arranged in the
processing position.
18. The method according to claim 16, wherein the first raw blank
is rotated in a first direction of rotation depending on the
measured thickness profile, and the second raw blank is rotated in
an opposite second direction of rotation depending on the measured
thickness profile.
19. The method according to any claim 16, wherein the raw blank is
rotated by 80.degree. to 100.degree., starting from the cut-off
position.
20. The method according to claim 16, wherein the processing device
comprises a punching tool or a beam cutting tool.
21. The method according to claim 16, wherein the raw blank is
separated from the strip material with a length of less than 2500
millimeters and more than 400 millimeters.
22. The method according to claim 16, wherein the raw blank is cut
off with a length that is greater than the width of the strip
material.
23. The method according to claim 16, wherein the strip material is
fed from a buffer device to a measuring device by a feeding device;
wherein determining the measured thickness profile comprises
continuously measuring the thickness of the strip material by a
thickness measuring unit and continuously measuring the length of
the strip material by a length measuring unit, while the strip
material is being fed, wherein measuring of the thickness in the
feed direction of the strip material is carried out upstream the
feeding device, and measuring of the length in the feed direction
of the strip material is carried out downstream a first feed unit
of the feeding device; calculating a feed length for the raw blank
to be separated from the strip material on the basis of the
determined measured thickness profile and comparing with a
respective desired thickness profile of the raw blank; and feeding
the strip material to the separating device by the feeding device
on the basis of the calculated feed length.
24. The method according to claim 16, wherein the length measuring
unit is referenced at a starting point with the thickness measuring
unit with respect to the length, wherein the length measuring unit
generates trigger signals and transmits them to the thickness
measuring unit, with the trigger signals serving as triggers for
performing thickness measurements of the thickness measuring
unit.
25. The method according to claim 16, wherein the separating device
comprises a first feed unit and a second feed unit for feeding the
strip material, wherein a fixed first distance is set between the
thickness measuring unit and the first feed unit, and wherein a
fixed second distance is set between the thickness measuring unit
and the separating device, wherein at least one of the first
distance and the second distance are measured with an accuracy of
up to +/-0.2 millimeters.
26. An apparatus for producing a product from flexibly rolled
metallic strip material, comprising: a feeding device for feeding
flexibly rolled metallic strip material, which has a thickness
profile with different sheet thicknesses along a length of the
strip material, wherein successive regions of the flexibly rolled
strip material correspond to a respective desired thickness profile
of a shaped blank to be produced therefrom; a measuring device for
determining the thickness of the strip material over the length of
the strip material; a separating device for producing individual
raw blanks from the flexibly rolled strip material, with the
separating device having a distance from a thickness measuring unit
of the measuring device which corresponds to at least twice the
length of a raw blank to be separated; a rotating device for
rotating a separated raw blank into a desired processing position,
wherein the rotating device is controllable by an electronic
control unit in order to rotate a separated raw blank into the
desired processing position depending on the determined measured
thickness profile of the raw blank; and a processing device which
is designed to produce a product from the raw blank in the
processing position.
27. The apparatus according to claim 26, wherein the electrical
control unit is configured to determine a first rotational movement
from a first strip region with a first thickness profile, and to
determine a second rotational movement, which differs from the
first rotational movement, from a second strip region with a second
thickness profile.
28. The apparatus according to claim 26, wherein the processing
device has at least one cutting tool which cuts a shape-cut blank
out of the blank.
29. The apparatus according to claim 26, further comprising: a
buffer device for temporarily buffering the flexibly rolled strip
material; a first feed unit, which is arranged downstream the
buffer device in the feed direction of the strip material; at least
one length measuring unit for continuously measuring the length of
the strip material, wherein the length measuring device is arranged
downstream the first feed unit in the feed direction of the strip
material; a thickness measuring unit for continuously measuring the
thickness of the strip material along the length, wherein the
thickness measuring unit is arranged between the buffer device and
the first feed unit in the feed direction of the strip material;
and a second feed unit, which is arranged downstream the first feed
unit and upstream the separating device; wherein the first feed
unit and the second feed unit are designed to move the strip
material from the buffer device to the separating device in
dependence on the thickness measurement and the length
measurement.
30. The apparatus according to claim 26, further comprising: a
decoiler for unwinding the flexibly rolled strip material and a
straightening unit for straightening the flexibly rolled strip
material, which are arranged upstream the buffer device, wherein
the first feed unit and the second feed unit for the separating
device are controlled independently of a feed of the decoiler and
the straightening unit.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a national stage of, and claims priority
to, Patent Cooperation Treaty Application No. PCT/EP2019/061598,
filed on May 6, 2019, which application claims priority to European
Application No. EP18174010.1, filed on May 24, 2018, which
applications are hereby incorporated herein by reference in their
entireties.
BACKGROUND
[0002] From CN 104551538 B a device and a method for separating
flexibly rolled strip material are known. The strip material is fed
from a coiler via a first clamping roller and a strip straightening
device into a strip buffer. Behind the strip buffer there are two
further clamping rollers with integrated length measurement,
between them a strip thickness measurement, and behind them a
hydraulic shear for separating the strip material.
[0003] From EP 3 181 248 A1 a process and an apparatus for
producing a sheet metal blank are known. The process comprises the
steps: flexible rolling of a strip material, wherein a thickness
profile with different sheet thicknesses is generated over the
length of the strip material; determining a measured thickness
profile of several successive regions of the strip material;
calculating a desired position in the strip material for a sheet
blank to be cut out of the strip material depending on the
generated measured thickness profile of at least two successive
regions of the strip material; cutting the flexibly rolled strip
material by means of at least one cutting device along the desired
position to produce the sheet blank.
[0004] The production of shape-cut or rectangular blanks from
flexibly rolled metal strip, also known as tailor rolled shapes or
tailor rolled blanks, is usually carried out using a suitable
cutting device. Depending on the length and thickness profile of
the blanks to be produced, efficient production is difficult. In
particular, components of variable sheet thickness with end
sections of varying thickness (in this case also referred to as A-B
rolling) cannot be produced or can only be produced with
considerable scrap. The scrap is caused by the fact that a
transition ramp has to be rolled into the strip material between
the end thickness of a first blank and the beginning thickness of
the following blank, which forms a scrap.
SUMMARY
[0005] The present disclosure relates to a process and an apparatus
for manufacturing a product from flexibly rolled strip material.
Flexibly rolled strip material has a variable thickness profile in
the longitudinal direction of the strip. The separation of flexibly
rolled strip material therefore requires an exact positioning of
the separation region in order to obtain blanks with a defined
nominal thickness profile.
[0006] The present process and an apparatus for producing products
from flexibly rolled strip material enables an efficient production
of blanks with high manufacturing accuracy even if the thickness
profiles in the strip material are not uniform. A corresponding
apparatus which enables fast and cost-efficient processing with
high manufacturing accuracy can produce products from flexibly
rolled strip material.
[0007] A method of producing a product from flexibly rolled strip
material, comprises: providing a flexibly rolled metallic strip
material having a thickness profile with a variable thickness along
the length of the strip material; determining a measured thickness
profile of the strip material along the length of the strip
material; and calculating a desired cutting position for a blank to
be produced from the strip material depending on the determined
measured thickness profile of the strip material and an associated
desired thickness profile of the blank to be cut therefrom; cutting
off a blank from the strip material along the desired cutting
position; rotating the blank depending on the determined measured
thickness profile such that the blank is positioned with its
thickness profile in a defined processing position which differs
from the cutting position; and processing the blank in the
processing position by means of a processing unit, the blank being
processed into a product.
[0008] This method allows blanks with variable thickness profile
(Tailor Rolled Blanks), which have different sheet thicknesses at
the opposite ends, and/or those with an asymmetrical sheet
thickness profile, or products made therefrom, to be produced
efficiently and with high manufacturing accuracy. The blanks are
correctly positioned before entering the contour cutting tool so
that the sheet thickness profile always matches the shape and/or
cutting contour in the tool. The correctly aligned raw blanks are
indexed into the following tool where they are further processed
into shaped cuts. Because the blanks, which have a greater length
than width in the rolling direction, are rotated before further
processing, the feed lengths of the blanks into the tool and during
transport through the tool are shortened, so that shorter cycle
times are achieved.
[0009] The raw blanks are further processed into a product in the
following processing unit. In the context of the present
disclosure, the term product shall include any intermediate or end
product that starting from the blank has undergone a shape-changing
further processing. These may be shape cut parts, for example, if
the further processing includes pure shape cutting, or formed
parts, if the further processing includes a forming process, or
combinations thereof, if the further processing includes shape
cutting and forming.
[0010] Separation is performed in particular in such a way that
blanks with a length of less than 2500 mm (millimetres), in
particular less than 2000 mm, are separated from the strip
material. Alternatively or additionally, blanks with a length of
more than 400 mm, in particular more than 600 mm, can be separated
from the strip material. According to a possible embodiment, the
raw blanks can be separated from the strip material in such a way
that a longest length of the raw blank in the feed direction of the
strip is greater than the width of the strip material. It is to be
understood that, depending on the technical requirements of the
finished product and/or for tooling reasons, raw blanks can also be
cut off whose length in the desired cutting position, i.e. in the
feed direction of the strip, is equal to or less than the width of
the strip. In this disclosure, the desired cutting position is
understood to be the position to which the strip is advanced and
positioned in accordance with the measured thickness profile in
order to cut off the respective blank. The position and/or
orientation of the blank after cutting and before rotating is also
called the cut-off position.
[0011] The strip material can have alternating strip regions with
different or equal, symmetrical or asymmetrical strip thickness
profiles over the length.
[0012] According to a first embodiment, the strip material can have
a first strip region with a first thickness profile and an
adjoining second strip region with a second thickness profile over
the length, with the first and second thickness profiles differing
from one another in the strip material, wherein a first blank is
separated from the strip material from the first strip region and a
second blank is separated from the strip material from the second
strip region, wherein the first blank and the second blank are
rotated in such a way that the first thickness profile and the
second thickness profile are aligned in the same way in the
processing position. The first thickness profile in the strip can
be mirror-symmetrical to the second thickness profile with respect
to a parting plane lying between the two strip regions. In the
strip, the two thickness profiles are different over the length,
i.e. not congruent, but after cutting and rotating they coincide.
In the rotated state, the two blanks with their respective
thickness profiles are aligned identically and can be fed to the
tool for further processing. For this purpose, the first blank can
be rotated in a first direction of rotation depending on the
measuring thickness profile and the second blank in an opposite
second direction of rotation depending on the measuring thickness
profile. This also applies to each subsequent first and second
blank.
[0013] Another possibility is that the successive strip regions and
the blanks to be produced therefrom can also have front and end
sections of equal thickness, but with an asymmetrical sheet
thickness profile with respect to a feed length center. In this
case, too, the blanks are rotated with respect to the thickness
profile so that they have the same orientation before entering the
processing tool and in the tool, respectively. Of course, blanks
with a symmetrical thickness profile can also be processed. Here,
the blanks can always be rotated in the same direction.
[0014] According to an embodiment, it is intended that the blank
starting from the initial position after having been cut off from
the strip, is rotated by 80.degree. to 100.degree., in particular
90.degree.. As described above, the rotation takes place in the
first or opposite second direction of rotation around a vertical
axis of the blank, depending on the thickness profile.
[0015] After rotation, the identically aligned blanks, which still
have straight side edges after separation, are fed to the
processing tool and cut to the desired shape and, as the case may
be, formed. The processing device may comprise, for example, one or
more stamping tools and/or one or more beam cutting tools and/or
one or more forming tools or combinations thereof.
[0016] The method may further comprise feeding the strip material
from a buffer device by means of a feeding device, in particular by
a first feeding unit and a second feeding unit. The measuring
thickness profile can be determined, for example, during the strip
feed by continuously measuring the thickness of the strip material
by a thickness measuring unit and continuously measuring the length
of the strip material by a length measuring device. The thickness
is preferably measured in the feed direction of the strip material
before the first feed unit, and the length is measured in the feed
direction of the strip material behind the first feed unit. On the
basis of the determined measuring thickness profile and comparison
with an associated desired thickness profile of the blank, a feed
length for the blank to be separated from the strip material can be
determined. The strip material is then fed to the separating device
by means of the first and second feed unit on the basis of the
calculated feed length.
[0017] According to an embodiment, the strip material can be pulled
out of the strip buffer by the position-controlled feeding device.
The flexible rolled strip can be continuously measured by the
thickness measuring unit with regard to its thickness. The
thickness measuring unit evaluates on the basis of the measured
thickness, under consideration of the associated length measurement
values, whether or not the flexible rolled strip meets the required
thickness tolerances. The comparison of the determined actual
thickness profile with the specified desired thickness profile is
carried out in particular also under consideration of the
associated tolerances of the desired thickness profile, which can
be represented by an envelope profile. In this case, it is verified
by calculation whether the determined actual profile lies within
the envelope profile of the desired profile. From the result of the
comparison the feed length for the strip or the blank to be
separated can be calculated. The strip is divided into regions that
are OK (so-called OK parts) and those that are not OK (so-called
not OK parts). The position and length of these individual regions
in the strip is passed on from the thickness measuring unit to the
first feed unit. The first feed unit, and the second feed unit
coupled to it, can then carry out the feeds instructed by the
thickness measuring unit and position the reference edges of the
individual feed lengths accurately to the separation point of the
separating device. The feed unit can then transmit the information
to the other apparatus components as to whether the feed length is
a feed length with an OK thickness profile or a not OK thickness
profile.
[0018] According to an embodiment, the first length measuring
device of the first feed is referenced at the starting point with
the thickness measurement with regard to length. This can be done
by continuous transmitting the measured length value from the first
length measuring device to the thickness measuring device.
Transmitting the length measuring values can be effected absolute
or incremental. The thickness measurement scales the thickness
measurement values based on the transmitted length measurement
values over the strip length. In this way both measuring devices
can work from exactly the same strip length zero point. According
to an embodiment, the length measuring device can generate trigger
signals and pass them on to the thickness measuring device, wherein
the trigger signals serve as triggers for carrying out thickness
measurements of the thickness measuring device.
[0019] According to an embodiment, a fixed distance can be set
between the thickness measuring unit and the first feed unit. This
distance is measured precisely, preferably with an accuracy of up
to +/-0.2 mm, and is maintained during operation of the line. In
this way, the length reference between the thickness measurement on
the one hand and the feed respectively length measurement on the
other hand can be reliably ensured over the entire length of the
strip material.
[0020] For accurately positioning a reference edge of a feed length
on a reference separation point of the separating device, a fixed
distance can be set between the thickness measuring device and the
separating device according to a possible embodiment. This distance
is measured precisely, preferably with an accuracy of up to +/-0.2
mm, and maintained during operation of the apparatus.
[0021] According to an embodiment, the second feed unit is operated
synchronously with the first feed unit, in particular with the same
length scale as the first feed unit and the thickness measuring
unit. By controlling the second feed unit such that it moves
slightly ahead of the first feed unit, the second feed unit
produces a slight strip tension in the strip portion that is within
the measuring section, which ensures a smooth strip run.
[0022] To solve the above mentioned object, an apparatus for
producing a product from flexibly rolled metallic strip material is
also proposed, comprising: a feeding device for feeding flexibly
rolled metallic strip material, which has a thickness profile with
different sheet thicknesses over the length of the strip material,
wherein successive regions of the flexibly rolled strip material
each correspond to an associated desired thickness profile of a
shaped blank to be produced therefrom; a measuring device for
determining the thickness of the strip material over the length of
the strip material; a separating device for producing individual
blanks from the flexibly rolled strip material, wherein the
separating device has a distance from a part of the measuring
device which amounts to at least twice the distance of a blank to
be cut off; a rotating device for rotating a separated blank into a
desired processing position, the rotating device being controllable
by an electronic control unit in order to rotate a separated blank
into the desired processing position depending on the determined
measuring thickness profile of the blank; a processing device which
is designed to produce a product, in particular a shaped cut part,
from the blank in the processing position.
[0023] There are similar advantages for the device as for the
process. The device enables blanks with a variable thickness
profile (Tailor Rolled Blanks), which have different sheet
thicknesses at the opposite ends and/or those with an asymmetrical
sheet thickness profile, to be produced efficiently and with high
production accuracy. It is to be understood that all method-related
features are analogously applicable to the apparatus, and vice
versa, all apparatus-related features are applicable to the
method.
[0024] The electronic control unit can be configured to determine a
first rotary motion from a first strip region with a first
thickness profile, and a second rotary motion from a second strip
region with a second thickness profile, which deviates from the
first rotary motion. For example, the control unit can derive on
the basis of the determined measured thickness profile of the metal
strip, respectively the thickness profile of the blank separated
therefrom, how the blank is to be aligned relative to the
subsequent tool to be further processed to the desired product.
[0025] The processing device may include one or more cutting groups
that cut the shaped blank from the raw blank in one or more
successive stages and/or one or more forming tools to form the
blank into a sheet metal formed part.
[0026] The apparatus may also include a transport device for
transporting the strip material through the measuring device and
the cutting device to the rotating device. The transport device can
have a variety of rolling elements on which the strip material
rests and is guided further.
[0027] A buffer device for temporarily buffering the flexibly
rolled strip material can also be provided upstream of the feeding
device. The feeding device may comprise a first feed unit, which is
arranged behind the buffer device in the feeding direction of the
strip material, and a second feed unit, which is arranged
downstream the first feed unit and upstream the separating device.
The first and second feed units are configured to move the strip
material from the buffer device to the separating device in
dependence on the thickness measurement and the length measurement.
The measuring device may comprise at least one length measuring
unit for continuously measuring the length of the strip material,
and one thickness measuring unit for continuously measuring the
thickness of the strip material along the length. The thickness
measuring unit is preferably arranged between the buffer device and
the first feed unit in the feed direction of the strip material.
The length measuring unit is preferably arranged behind the first
feed unit in the feed direction of the strip material.
[0028] Upstream of the buffer device, the apparatus may also
include a decoiler for uncoiling the flexibly rolled strip material
and one or more straightening units arranged in series for
straightening the flexibly rolled strip material. In particular, it
is intended that the feeding device for the separation of the strip
material into blanks is controlled independently of the feed of the
coiler and the straightening unit.
[0029] Overall, the apparatus and the method are advantageous for
inspecting, precise positioning and separation of flexibly rolled
strip material into tailored rolled blanks and subsequent further
processing into shaped cuts and/or pressed parts.
BRIEF SUMMARY OF THE DRAWINGS
[0030] Preferred embodiments are explained below using the drawing
figures. Herein shows:
[0031] FIG. 1a method and/or apparatus for producing a product from
flexibly rolled metal strip in a first embodiment;
[0032] FIG. 2a method and/or apparatus for producing a product from
flexibly rolled metal strip in a modified embodiment;
[0033] FIG. 3 shows the thickness profile of an exemplary blank
which can be produced with the method and apparatus according to
FIG. 1 and/or FIG. 2;
[0034] FIG. 4 parts of the apparatus from FIG. 1 in a
three-dimensional representation for producing blanks according to
FIG. 3;
[0035] FIG. 5 shows the thickness profile of another exemplary
blank which can be produced with the method and apparatus according
to FIG. 1 and/or FIG. 2;
[0036] FIG. 6 shows the thickness profile of another exemplary
blank which can be produced with the method and apparatus according
to FIG. 1 and/or FIG. 2;
[0037] FIG. 7 part of the apparatus from FIG. 1 in a
three-dimensional representation for producing blanks according to
FIG. 6;
[0038] FIG. 8 further optional apparatus components of an apparatus
according to the invention schematically in three-dimensional
representation.
DESCRIPTIONS WITH REFERENCE TO THE DRAWINGS
[0039] FIGS. 1 to 8 are described together below, with reference to
special features of individual figures.
[0040] FIG. 1 shows a process and individual components of an
apparatus 2 for producing a product from a flexibly rolled metal
strip. The method comprises the steps of providing S1 a flexibly
rolled strip material 3, determining S20 a measured thickness
profile D3 of the strip material 3 and calculating a desired
cutting position for a blank 4 to be cut from the strip material,
and feeding 510 of the strip material 3 to the desired cutting
position, cutting S30 of the blank 4 from the strip material 3
along a nominal cutting line 32 in the desired cutting position,
rotating S40 the blank 4 depending on the determined measurement
thickness profile into a defined processing position P50 for
further processing, and processing S50 of the blank 4 to the
product 5. The associated apparatus components are a feeding device
10, a measuring device 20, a separating device 30, a rotating
device 40 and a processing device 50.
[0041] A flexible rolled strip material is understood to be a metal
strip that has a variable sheet thickness over its length. A
variable sheet thickness profile can be produced by rolling a strip
material with a substantially constant starting sheet thickness by
rolling with dynamical variation of the roll gap. The strip
material is given different thicknesses D3 over the length L3 in
the rolling direction. After flexible rolling, the strip material 3
can be wound up into a coil 1 so that it can be fed to the next
processing step.
[0042] The feeding device 10 can have one or more feed units 11, by
which the strip material is moved in feed direction R3. A feed unit
can have two feed rollers between which the strip material 3 is fed
through and moved in the feed direction by rotatingly driving the
feed rollers 11.
[0043] The measuring device 20 may comprise at least a length
measuring unit 21 for continuously measuring the length L of the
strip material 3, and a thickness measuring unit 22 for
continuously measuring the thickness D3 of the strip material 3
along its length. The calculation of the desired cutting position
for the blank 4 to be separated is then carried out depending on
the determined measurement thickness profile D3 of the strip
material 3 and the associated desired thickness profile of the
blank 4 to be cut therefrom. The length measuring unit 21 can
comprise a measuring wheel 23, which is in contact with one side of
the strip material 3, and optionally a support wheel 24, which is
in contact with the opposite side of the strip material 3 as a
counter support for the measuring wheel.
[0044] The length measuring unit 21 and the thickness measuring
unit 22 can be coupled with each other in a measuring-technical
manner. For a reliable maintaining the length reference over the
strip length between the thickness measurement 22 on the one hand
and the first feed unit 11 and/or the first length measurement 21
on the other hand, a fixed distance A1 is set between the thickness
measuring unit 22 and the first feed unit 11. This distance A1 is
measured precisely, preferably with an accuracy of up to +/-0.2 mm,
and maintained during operation of the line. In this way, the
length reference between the thickness measurement on the one hand
and the feed and/or length measurement on the other hand can be
reliably ensured over the entire length of the strip material.
During operation of the apparatus 2, the length measuring unit 21
can generate 21 trigger signals B1 and transmit them to the
thickness measuring unit 22. Each trigger signal B1 serves as a
trigger for a thickness measurement, so that with each trigger
signal of the length measuring unit 21 a thickness measuring value
is generated and assigned to a corresponding length measuring
value. In this way, data sets of pairs of length and thickness
values are generated, from which the actual thickness profile of
the blank 4 to be cut out of the strip material 3 can be
determined.
[0045] The separating device 30 can be selected according to the
requirements of the flat product 4 to be separated and can
comprise, for example, a cut-to-length shear 31, as shown
schematically, or a cut-to-length beam cutting unit, in particular
a laser cutting unit. The separation of a raw blank 4 from the
strip material 3 is performed along a nominal cutting edge 32 in
the desired cutting position P30, into which the strip has been
advanced and positioned by the feeding device 10. In particular,
the present method and apparatus are used to produce blanks 4 whose
longest length L4 is greater than the width B3 of the strip
material 3, which corresponds to the width B4 of the blank 4 to be
cut off. In particular, it is further provided that blanks 4 with a
length L4 of less than 2500 mm, in particular less than 2000 mm,
and/or with a length of more than 400 mm, in particular more than
600 mm, are separated from the strip material.
[0046] The distance A2 between the thickness measuring unit 22 and
the separating device 30 is preferably at least twice the blank
length L4 of the blank 4 to be cut out of the strip material 3. In
particular, the distance A2 is at least twice the blank length plus
the feed path covered by the strip material 3 during the computing
time for a blank 4 to be cut out.
[0047] In particular, the apparatus and/or method is configured
such that the thickness profiles determined by the measuring device
20 are compared with the desired nominal thickness profile. The
control unit 26 evaluates whether or not the flexible rolled strip
3 meets the required thickness tolerances. From the result of the
comparison, the feed length for the strip 3, respectively the blank
4 to be cut out therefrom can be determined. The strip can be
divided into regions that are OK (so-called OK parts) and those
that are not OK (so-called not OK parts). The position and length
of these individual regions in the strip 3 is transmitted by the
thickness measuring device 20 to the feeding device 10, which
carries out the instructed feeds accordingly and positions the
reference edges of the individual feed lengths accurately to the
separation point 32 of the separating device 30. The feeding device
10 can transmit the information to the other apparatus components
(30, 40, 50) as to whether the feed length has an OK thickness
profile or not.
[0048] After the blank 4 has been cut off, it is rotated about a
vertical axis A40 in the rotating device 40. The rotating device
can be designed and configured to meet the requirements of the
blanks to be rotated. For example, the rotating device 40 can
comprise a number of suction cups 41, which are attached to a
movable carrier 42. Using the rotating device 40, the blank 4 is
rotated from the starting position P30 after cutting from the strip
3, in which the blank 4 is still aligned in the direction R3 of
strip 3, depending on the measured thickness profile D3 so that it
is aligned with its thickness profile D4 in a defined processing
position P50. In particular, it is intended that one or more tools
of the further processing device 50 are aligned transversely to the
strip feed direction R so that the blanks 4 are each rotated by
90.degree. from the cut-off position P30 to the processing position
P50.
[0049] After rotating S40, the equally aligned raw blanks 4 are fed
to the further processing device 50. The processing device 50 is
selected according to the requirements of the product 5 to be
manufactured. In an embodiment shown in FIGS. 1, 4 and 7, the
device 50 is configured as a cutting device. In the cutting device
50, the edges of the raw blank 4 are cut off in order to produce a
shape cut blank 5 with a desired outer contour. According to a
possible embodiment, the cutting device 50 can comprise a lower
tool part 51 and a movable upper tool part 52. The lower tool part
51 can be positioned and fixed on a table 53. The upper tool part
52 can be attached to a press ram 54 which is movably guided
relative to the table 53 via guide bushes 55.
[0050] According to a second embodiment, which is shown in FIG. 2,
the processing device 50 includes a cutting and forming tool. The
design and function are similar to those of the cutting device
described above. Therefore, the same details are marked with the
same reference signs as in FIG. 1. The only difference is that in
addition to generating the shape cut, the intermediate product is
formed into a three-dimensional component 5 in a forming tool. The
components produced in this way can also be referred to as
press-formed parts or stamped parts. To produce press-formed parts
5, the device 50 can have a combined cutting and forming tool
(punching tool) with which the press-formed part is produced in one
step. Alternatively, the device 50 can also comprise several
processing steps arranged one after the other with respective
tools, which are passed through one after the other by the part to
be produced. In particular, at least one cutting tool, in which the
blank 4 is cut to form the shape-cut blank, and at least one
downstream forming tool, in which the shape-cut blank is formed to
the press-formed part 5, may be provided.
[0051] Strip material 3 can have alternating strip regions with
different or equal, symmetrical or asymmetrical strip thickness
profiles D3 over the length L3.
[0052] FIGS. 3, 5 and 6 show different forms of blanks 4 to be
produced from strip material 3, wherein FIG. 4 shows a method
suitable for processing blanks 4 as shown in FIGS. 3 and 5, and
wherein FIG. 7 shows a method suitable for processing blanks 4 as
shown in FIG. 6.
[0053] FIG. 3 shows an exemplary blank 4 in the form of a
rectangular blank with an asymmetrical thickness D4 over the length
L4 of the blank and with end sections of equal thickness.
Specifically, the blank 4 has six different sections 7a, 7b, 7c, 7d
with different thicknesses D7a, D7b, D7c, D7d starting from the
first end, with the first section 7a and the last section 7d at the
second end 8 having the same thickness (D7a=D7d). Between every two
sections 7a, 7b, 7c, 7d of constant thickness, which can also be
called plateaus, a transition section 9a, 9b, 9c of variable
thickness is formed, which can also be called ramps. The
rectangular blank 4 shown in FIG. 3 is produced by simply cutting
the strip material 3, which has been brought to the correct cutting
position P30 by the feeding device 10, for example by using a
cutting shear 31.
[0054] FIG. 4 shows a corresponding method for the processing of
blanks 4 with a sheet thickness profile according to FIG. 3 by an
apparatus 2 according to the invention. The different thicknesses
D7a, D7b, D7c, D7d=D7a of the blank from FIG. 3 are shown here in
simplified form only with a, b, c, a. It can be seen that starting
from the separating position P30 the raw blanks 4 are all rotated
uniformly in the same direction of rotation R40, in this case
counter-clockwise, to the further processing position P50. At the
same time, the blank 4 can also be moved in feed direction V40.
After the blanks 4 have been rotated, they are all uniformly
arranged transverse to the strip feed direction 10, that is with
the same orientation of the sheet thickness profiles a, b, c, a. In
the cutting or punching tool 50, the rotated blanks 4 are cut in
cycles to form cuts 5 with a desired peripheral contour. Parts
identified by the control unit as "not OK" blanks can be ejected
and scrapped between the cutting device 30 and the processing
device 50. This can be done by the rotating device 40 or a separate
ejection device. The "OK" products 5 can be stacked behind the
device 50 by a stacking unit (not shown).
[0055] FIG. 5 shows another embodiment of a rectangular blank 4,
which in contrast to FIG. 3 has a symmetrical thickness D4 over the
length L4. It can be seen that the thickness D4 of the blank 4 is
mirror-symmetrical in relation to a center plane E. The blank 4
shown here can be processed in the same way as the blank shown in
FIG. 3 using the process shown in FIG. 4 which is why, to avoid
repetition, reference is made to the above description.
[0056] FIG. 6 shows an embodiment of blanks with end sections
having a different thickness. For this reason, two successive blank
regions 3A, 3B in the strip 3 are arranged mirrored to each other.
Over the length L3 of the strip 3, a first strip region 3A, from
which a first blank 4A is to be separated, and a second strip
region 3B, from which a second blank 4B is to be separated,
alternate. Here, the profile of the first strip region for a first
blank 4A corresponds to the profile of the strip region for a
second blank 4B with regard to the profile shape, but not with
regard to the alignment. Furthermore, the blanks 4A, 4B shown here
have an asymmetrical thickness profile D4A, D4B over the respective
length L4A, L4B. It can be seen that the thickness D4A of the blank
4A in relation to a center plane EAB is mirror-symmetrical to the
thickness D4B of the following blank 4B. The blank 4A has, starting
from the first end 6A, a first section 7Aa with a first thickness,
a second section 7Ab with a second thickness, a third section 7Ac
with a third thickness, and a fourth section 7Ad with a fourth
thickness different from the first thickness of the first section
7Aa. Between the sections 7Aa, 7Ab, 7Ac and 7Ad, each having a
constant thickness along the length, there are transition sections
9Aa, 9Ab, 9Ac and 9Ad with variable thickness along the length. The
second blank 4B is accordingly symmetrical to the first blank 4A.
The second blank 4B is followed by a first blank 4A, and so on.
[0057] FIG. 7 shows a corresponding method for processing blanks
4A, 4B with sheet thickness profiles according to FIG. 6, wherein
the different thicknesses D7a, D7b, D7c, D7d of the blanks 4A, 4B
from FIG. 6 are shown in simplified form with a, b, c, d. The
rectangular blanks 4A, 4B are separated by means of the separating
device 30 through cross-cutting the strip material 3, brought to
the correct cutting position 32 by the feeding device 10, and then
rotated to the desired position P50. A special feature is that the
thickness profiles D4A and D4B differ from each other in that they
are not congruent in their arrangement in the strip material. To
ensure that the successive first and second blanks 4A, 4B receive
the same orientation for further processing, the first and second
blanks 4A, 4B are rotated individually by the rotating device 50
according to their respective profile orientation. For this
purpose, the first blanks 4A are rotated depending on the measuring
thickness profile D4A in a first direction of rotation R40A
(counter-clockwise in this case) and the second blanks 4B are
rotated depending on the measuring thickness profile D4B in the
opposite, second direction of rotation R40B (clockwise in this
case). After rotating and positioning in the processing position
P50, the first and second blanks with their respective thickness
profile are now aligned identically and are therefore uniform. In
this alignment, the blanks 4 are fed to the further processing
device 50, which can be configured according to one of the above
described embodiments.
[0058] With the method and apparatus, blanks 4 with variable
thickness profile (Tailor Rolled Blanks), which have different
sheet thicknesses at the opposite ends and/or those with an
asymmetrical sheet thickness profile, can be produced efficiently
and with high production accuracy. The blanks 4, 4A, 4B are
correctly aligned before entering the contour cutting tool so that
the sheet thickness profile always matches the shape or cutting
contour in the tool. The correctly aligned blanks 4 are fed into
the following tool 50 and processed there into shaped cuts or
press-formed parts. As the blanks 4, 4A, 4B, which have a greater
length L4 than width B4 in the rolling direction, are turned before
further processing, the feed length of the blanks into and/or
through the tool is shortened so that shorter cycle times are
achieved overall.
[0059] FIG. 8 shows further optional apparatus components of an
apparatus according to the invention in three-dimensional
representation.
[0060] An uncoiling and straightening group 60, a buffer device 70
and an example of a downstream feed and separation group 15 are
shown. The starting material is a coil 1 of flexibly rolled metal
strip which is unwound from a decoiler 61 and then passes through a
straightening unit 62 with a plurality of rolls. Between the
decoiler 61 and the straightening unit 62, an infeed driver 63 can
be provided to pull the strip material 3 from the decoiler and feed
it to the straightening unit 62. A take-off roller 64 can be
arranged in the processing direction behind the straightening unit
62, which take-off roller 64 transmits a feed force to the strip
material 3. The operation of the apparatus components, i.e. the
decoiler, infeed driver, straightening unit and take-off roller,
can be synchronized with each other via controllers and operated in
speed control or torque control mode. Each of the units can be
operated individually, i.e. independently of the others, in a
generator or motor mode. FIG. 1 shows the torques M61, M62, M63,
M64 that can be transmitted from the respective components 61, 62,
63, 64 to the strip material 3.
[0061] In the strip feed direction behind the uncoiling and
straightening group 60, a buffer device 70 is provided, which is
designed to temporarily store a respective section of strip 3. This
decouples a feed movement of the uncoiling and straightening group
60 from a feed movement of the following apparatus components
(10-50). The uncoiling and straightening group 60 conveys the strip
3 to the strip buffer 70, which makes the flexibly rolled strip 3
available for further processing in the separation group 15. The
conveying and/or unwinding speed of the uncoiling and straightening
group 60 can be controlled by a level sensor 71 of the strip buffer
70. The level sensor 71 can, for example, include an ultrasonic
sensor or an optical sensor which senses the depth of the strip
loop hanging in the strip buffer and transmits a corresponding
signal to the controller for the uncoiling and straightening
group.
[0062] Behind the buffer device 70, the apparatus components
already described above are the feeding device 10, measuring device
20 and separating device 30. In the present embodiment, the feeding
device 10 comprises a first feed unit 11 and a second feed unit 12,
which are arranged at a distance from each other. Furthermore, the
measuring device comprises a further length measuring unit 25 in
addition to the thickness measuring unit 22 and the length
measuring unit 21. It can be seen that the thickness measuring unit
22 for continuous measurement of the thickness D3 of the strip
material 3 is arranged in front of the first feed unit 11, and that
the first length measuring unit 21 for continuous measurement of
the length L3 of the strip material 3 is arranged behind the first
feed unit 11. The second length measuring unit 25 is assigned to
the second feed unit 12 and arranged behind same in feed direction
R10.
[0063] The two feed devices 11, 12 are operated synchronously and
are designed to move the strip material 3 from the buffer device 70
to the separation device 30 in dependence on the thickness
measurement and the length measurement. The two feeds 11, 12 each
exert a feed force on the strip material to move it. To ensure that
the strip material is held flat between the two feed devices 11,
12, the second feed device 12 can be driven with a slight advance
relative to the first feed device 11.
LIST OF REFERENCE SIGNS
[0064] 1 coil [0065] 2 apparatus [0066] 3 strip material [0067] 4
raw blank [0068] 5 product [0069] 6 end [0070] 7 section [0071] 8
end [0072] 9 transition section [0073] 10 feeding device [0074] 11
feed unit [0075] 12 feed unit [0076] 13 feed roller [0077] 15
separation group [0078] 20 measuring device [0079] 21 length
measuring unit [0080] 22 thickness measuring unit [0081] 23
measuring wheel [0082] 24 support wheel [0083] 25 length measuring
unit [0084] 30 separation device [0085] 31 cut-to-length shear
[0086] 32 [0087] 40 rotating device [0088] 41 suction cup0 [0089]
42 carrier [0090] 50 further processing device [0091] 51 lower tool
part [0092] 52 upper tool part [0093] 53 press table [0094] 54
press ram [0095] 55 guide bushes [0096] 60 uncoiling and
straightening group [0097] 61 coiler [0098] 62 straightening unit
[0099] 63 infeed driver [0100] 64 take-off roller [0101] 70 buffer
device [0102] 71 level sensor [0103] A distance [0104] B trigger
signal [0105] D thickness [0106] E level [0107] L length [0108] M
torque [0109] P position [0110] R direction [0111] S step
* * * * *