U.S. patent application number 15/016499 was filed with the patent office on 2016-08-11 for two-blow heating and forming tool and method for producing hot-formed and press-hardened motor vehicle components.
This patent application is currently assigned to BENTELER Automobiltechnik GmbH. The applicant listed for this patent is BENTELER Automobiltechnik GmbH. Invention is credited to Georg FROST, Ulrich HUSCHEN, Josef KOESTER, Stefan KONRAD, Jan LACKMANN, Oliver LUETKEMEYER, Max NIESSE.
Application Number | 20160228934 15/016499 |
Document ID | / |
Family ID | 56498180 |
Filed Date | 2016-08-11 |
United States Patent
Application |
20160228934 |
Kind Code |
A1 |
FROST; Georg ; et
al. |
August 11, 2016 |
TWO-BLOW HEATING AND FORMING TOOL AND METHOD FOR PRODUCING
HOT-FORMED AND PRESS-HARDENED MOTOR VEHICLE COMPONENTS
Abstract
A two-blow heating and forming tool for the simultaneous
production of two hot-formed and press-hardened motor vehicle
components is provided. The tool includes a heating device and a
forming device, with at least two contact heating tools and at
least two hot-forming and press-hardening tools being arranged next
to one another in parallel in a press such that, during a closing
movement, two blanks are heated and two heated blanks are
hot-formed and press-hardened to form two motor vehicle components.
A method for producing hot-formed and press-hardened motor vehicle
components using a two-blow heating and forming tool is also
provided, the method including producing two mirror-inverted motor
vehicle components simultaneously in one press cycle.
Inventors: |
FROST; Georg; (Steinheim,
DE) ; NIESSE; Max; (Paderborn, DE) ;
LUETKEMEYER; Oliver; (Paderborn, DE) ; LACKMANN;
Jan; (Paderborn, DE) ; KONRAD; Stefan;
(Paderborn, DE) ; HUSCHEN; Ulrich; (Lichtenau,
DE) ; KOESTER; Josef; (Hoexter, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BENTELER Automobiltechnik GmbH |
Paderborn |
|
DE |
|
|
Assignee: |
BENTELER Automobiltechnik
GmbH
Paderborn
DE
|
Family ID: |
56498180 |
Appl. No.: |
15/016499 |
Filed: |
February 5, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B21D 35/003 20130101;
B21D 22/208 20130101; B21D 37/16 20130101 |
International
Class: |
B21D 26/021 20060101
B21D026/021 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 5, 2015 |
DE |
102015101668.0 |
Claims
1. A two-blow heating and forming tool for the simultaneous
production of two hot-formed and press-hardened motor vehicle
components, comprising at least two contact heating tools and at
least two hot-forming and press-hardening tools which are arranged
in parallel next to one another in a press, such that, during a
closing movement, two blanks are heated and two heated blanks are
hot-formed and press-hardened to form two motor vehicle
components.
2. The heating and forming tool as claimed in claim 1, wherein the
two contact heating tools and/or the two hot-forming and
press-hardening tools are mounted resiliently.
3. The heating and forming tool as claimed in claim 1, wherein the
two contact heating tools and/or the two hot-forming and
press-hardening tools are mounted resiliently on a top die.
4. The heating and forming tool as claimed in claim 1, wherein the
two hot-forming and press-hardening tools are designed as combined
hot-cutting and/or hot-perforating tools.
5. The heating and forming tool as claimed in claim 1, wherein a
conveyor is provided which transfers the heated blanks from the
contact heating tools into the hot-forming and press-hardening
tools.
6. The heating and forming tool as claimed in claim 5, wherein the
heated blanks are transferred by the conveyor from the contact
heating tools into the hot-forming and press-hardening tools in a
time less than or equal to the press cycle.
7. The heating and forming tool as claimed in claim 5, wherein the
heated blanks are transferred by the conveyor from the contact
heating tools into the hot-forming and press-hardening tools in a
time that is a part of the press cycle.
8. The heating and forming tool as claimed in claim 1, wherein a
mechanical press or a hydraulic press is used.
9. The heating and forming tool as claimed in claim 1, wherein a
servopress is used.
10. The heating and forming tool as claimed in claim 1, wherein the
contact heating tools have at least one contact plate heated by an
inductor.
11. The heating and forming tool as claimed in claim 1, wherein the
contact heating tools have at least one contact plate that is
formed by an electrically heatable conductor.
12. The heating and forming tool as claimed in claim 1, wherein the
contact heating tools have one electric compensating element each,
wherein a current-conducting cross-sectional area of the
compensating element added to the current-conducting
cross-sectional area of the blank to be heated form an overall
current-conducting cross-sectional area, wherein, by configuration
of the overall current-conducting cross-sectional area, a
homogeneous heating of the blank takes place in a targeted
manner.
13. The heating and forming tool as claimed in claim 1, wherein the
contact heating tools have one electric compensating element each,
wherein a current-conducting cross-sectional area of the
compensating element added to the current-conducting
cross-sectional area of the blank to be heated form an overall
current-conducting cross-sectional area, wherein, by configuration
of the overall current-conducting cross-sectional area, a partially
differing heating takes place in a targeted manner.
14. The heating and forming tool as claimed in claim 1, wherein the
contact heating tools and/or the hot-forming and press-hardening
tools are resiliently mounted so as to be relatively movable on a
support plate of the press.
15. The heating and forming tool as claimed in claim 1, wherein the
contact heating tools and/or the hot-forming and press-hardening
tools each have an additional trimming tool and/or perforating
tool.
16. The heating and forming tool as claimed in claim 1, wherein an
elastic adjusting element is arranged between hot-forming and
press-hardening tool and press, as a result of which the hot
forming is already completed before the press is completely closed,
and the remaining closing distance of the press leads to
compression of the elastic adjusting element.
17. The heating and forming tool as claimed in claim 1, wherein an
elastic element is incorporated between contact heating tool and
press table, the elastic element compensating for a thermal
expansion of the contact heating tool.
18. The heating and forming tool as claimed in claim 1 wherein a
linear conveyor system which is formed from at least two rails
lying opposite in parallel is provided along heating and forming
tool, the rails being shiftable in at least one translatory
direction and gripping elements being arranged on the rails, the
gripping elements being shiftable in the axial direction of the
rails, and wherein the gripping elements are raisable and lowerable
in the vertical direction (V) orthogonally to the axial direction
of the rails.
19. The heating and forming tool as claimed in claim 18, wherein
the rails are shiftable orthogonally to the axial direction thereof
and outward or inward with respect to the heating and forming tool,
and/or wherein the rails are shiftable in the axial direction
thereof for transporting the blanks and motor vehicle
components.
20. A method for producing hot-formed and press-hardened motor
vehicle components using a two-blow heating and forming tool
comprising: providing a two-blow heating and forming tool for the
simultaneous production of two hot-formed and press-hardened motor
vehicle components, said tool including at least two contact
heating tools and at least two hot-forming and press-hardening
tools which are arranged in parallel next to one another in a
press, such that, during a closing movement, two blanks are heated
and two heated blanks are hot-formed and press-hardened to form two
motor vehicle components; and simultaneously producing two
mirror-inverted motor vehicle components in one press cycle.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a two-blow heating and
forming tool for the simultaneous production of two hot-formed and
press-hardened motor vehicle components and a method for producing
motor vehicle components.
[0003] 2. Description of the Prior Art
[0004] It is known from the prior art to produce motor vehicle
components as formed sheet-metal components made from steel
materials. For this purpose, steel blanks are provided and are
placed into a press-forming tool and, by closing of the
press-forming tool, are shaped three-dimensionally and then form
the motor vehicle component.
[0005] Furthermore, the hot-forming and press-hardening technology
is established in the prior art. It is possible in this case to
increase the strength of motor vehicle components with the same or
even reduced wall thicknesses by thermal treatment. To this end,
the blanks are austenitized, consequently heated to a temperature
above the AC3 point and hot-formed in said austenitized condition.
This immediately affords the advantage that the degrees of freedom
in terms of shaping are also increased because of the heated blank.
After the shaping has ended, the motor vehicle component produced
in this manner is quenched and the initially austenitic material
structure is converted into an at least partial, in particular
complete high-strength martensitic material structure. In
particular, this takes place in the press tool preferably after the
press-forming operation has finished, and therefore this operation
is also referred to as press-hardening.
[0006] EP 2 014 777 B1 discloses a method and an apparatus for
tempering a steel sheet body, in which a metal blank is heatable by
contact heating by means of two contact plates. A rapid and
targeted admission of heat into the blank can take place here and
therefore, for example, a blank can be austenitized for subsequent
hot forming.
[0007] Furthermore, DE 10 2012 021 031 A1 discloses a method for
producing press-hardened sheet-metal components, in which at least
one steel sheet is heated without a furnace by means of an inductor
or a pressed-on contact plate and is then transferred into one or
more press steps connected one behind another.
SUMMARY OF THE INVENTION
[0008] It is the object of the present invention, starting from the
abovementioned prior art, to demonstrate a possibility of
efficiently reducing the production costs, the required production
area and the production time for producing hot-formed and
press-hardened components.
[0009] The abovementioned object is achieved by a two-blow combined
heating and forming tool for the simultaneous production of two
hot-formed and press-hardened motor vehicle components including at
least two contact heating tools and at least two hot-forming and
press-hardening tools which are arranged in parallel next to one
another in a press such that, during a closing movement, two blanks
are heated and two heated blanks are hot-formed and press-hardened
to form two motor vehicle components. The method part of the object
is furthermore achieved by a method for producing hot-formed and
press-hardened motor vehicle components using a two-blow heating
and forming tool having at least two contact heating tools and at
least two hot-forming and press-hardening tools which are arranged
in parallel next to one another in a press such that, during a
closing movement, two blanks are heated and two heated blanks are
hot-formed and press-hardened to form two motor vehicle components.
According to the method and using the tool, two mirror-inverted
motor vehicle components are simultaneously produced in one press
cycle.
[0010] Advantageous variant refinements of the present invention
include: 1) mounting the two contact heating tools and/or the two
hot-forming and press-hardening tools resiliently, in particular on
a top die; 2) designing the two hot-forming and press-hardening
tools as combined hot-cutting and/or hot-perforating tools; 3)
providing a conveyor which transfers the heated blanks from the
contact heating tools into the hot-forming and press-hardening
tools, in particular in a time less than or equal to the press
cycle, preferably in a part of the press cycle; 4) using a
mechanical press, in particular a servopress, or using a hydraulic
press; 5) providing the contact heating tools with at least one
contact plate, wherein the contact plate is preferably heated by an
inductor, or wherein the contact plate is formed by an electrically
heatable conductor; 6) providing the contact heating tools with one
electric compensating element each, wherein a current-conducting
cross-sectional area of the compensating element added to the
current-conducting cross-sectional area of the blank to be heated
forms an overall current-conducting cross-sectional area, wherein,
by configuration of the overall current-conducting cross-sectional
area, a homogeneous heating of the blank takes place or a partially
differing heating takes place in a targeted manner; 7) resiliently
mounting the contact heating tools and/or the hot-forming and
press-hardening tools so as to be relatively movable on a support
plate of the press; 8) providing the contact heating tools and/or
the hot-forming and press-hardening tools with an additional
trimming tool and/or perforating tool; 9) arranging an elastic
adjusting element between a hot-forming and press-hardening tool
and press, as a result of which the hot forming is already
completed before the press is completely closed, and the remaining
closing distance of the press leads to compression of the elastic
adjusting element; incorporating an elastic element between contact
heating tool and press table, the elastic element compensating for
a thermal expansion of the contact heating tool, in particular of a
segmented contact heating tool; 10) providing a linear conveyor
system, formed from at least two rails lying opposite in parallel,
along heating and forming tool, the rails being shiftable in at
least one translatory direction and gripping elements being
arranged on the rails, the gripping elements being shiftable in the
axial direction of the rails, and wherein the gripping elements are
raisable and lowerable in the vertical direction (V) orthogonally
to the axial direction of the rails; and/or 11) enabling the rails
to be shiftable orthogonally to the axial direction thereof and
outward or inward with respect to the heating and forming tool,
and/or wherein the rails are shiftable in the axial direction
thereof for transporting the blanks and motor vehicle components.
These and other advantageous embodiments will be discussed in
greater detail hereinafter.
[0011] The two-blow heating and forming tool for producing two
hot-formed and press-hardened motor vehicle components has a region
with a heating device and a region with a forming device. The
heating and forming tool is distinguished in that at least two
contact heating tools and at least two hot-forming and
press-hardening tools are arranged next to one another in parallel
in a press, such that, during a closing movement, two blanks are
heated and two motor vehicle components are hot-formed and
press-hardened, consequently in one press cycle. The tools are
preferably activated via a press drive or with a plurality of press
drives, which are, however driven synchronously, and therefore the
heating device and the forming device are closable at least
overlapping in time or simultaneously.
[0012] "Two-blow" within the context of the present invention means
that the at least two hot-forming and press-hardening tools drop
simultaneously and therefore two components are produced
simultaneously. The two contact heating tools likewise drop
parallel thereto and heat two blanks, the two heated blanks then
being transferred into the hot-forming and press-hardening tools
after opening and then being correspondingly formed upon renewed
closing. Two new cold blanks are then placed here into the contact
heating tools and heated. Within the context of the present
invention, the heating and forming tool may also be of three-blow
design by which three components are then produced simultaneously
in one press cycle. It is also possible for the heating and forming
tool to be of four-blow design; consequently, four components are
produced simultaneously.
[0013] The heating and forming tool according to the present
invention for the simultaneous production of two hot-formed and
press-hardened components is suitable in particular for producing
left/right components. For example, in the event of the production
of motor vehicle bodies, a left motor vehicle pillar and a right
motor vehicle pillar can be produced. For example, door impact
supports or hot-formed and press-hardened reinforcing patches can
also be produced simultaneously.
[0014] A significant space saving in a production factory turns out
to be a particular advantage since the two heating stations, two
transfer devices and two forming presses that are otherwise
required for producing two different components are integrated into
a combined heating and forming tool in a space-saving manner.
[0015] In a preferred variant embodiment, a conveyor is furthermore
provided, the conveyor replacing the transfer devices between
separate heating station and separate forming device. The space
required by such a transfer device for the handling, for example
the pivoting space of an industrial robot, can therefore also be
omitted in a space-saving manner in the apparatus according to the
present invention. Furthermore, it is also not necessary to
separately operate four presses which are movable up and down, but
rather all of the functions can be integrated in one press. By
eliminating the handling time which a transfer device would require
for transferring the blank from the separate heating device to the
separate forming device, the production time can simultaneously be
reduced and, overall, the production costs of the components can be
reduced because of lower operating costs. A further resulting
advantage is that, with the supply of one batch of sheet-metal
blanks, it is ensured that, in particular when producing left/right
components, production differences between different deliveries of
semi-finished products or starting materials are avoided. The
left/right components produced simultaneously in each case are
therefore equivalent, based on the delivered batch of sheet-metal
blanks to be processed. The number of rejects is, in turn, reduced,
as a result of which the production costs drop overall. The range
of fluctuation of the strength profile in the components is reduced
by means of short transfer distances/times and therefore the
product quality is increased.
[0016] In order to compensate for tolerances which differ from one
another and/or due to distortion of the respective press table, the
two contact heating tools and/or the two hot-forming and
press-hardening tools are mounted resiliently, in particular on a
top die of the press. The resilient mounting or the mounting with a
different compensating element makes it possible to compensate for
the thermal distortion during operation. Also, by means of
different coordination of the compensating elements or springs, in
particular the length thereof, and/or before the compensating
elements or springs are configured, the absolute contact during the
closing movement of the press can be temporally determined. For
example, the hot-forming and press-hardening tools can be mounted
with a compensating element or spring element which is longer than
the compensating element or spring element of the contact heating
tools. During the closing movement of the press, the hot-forming
and press-hardening tools therefore first of all come into contact
with the metal blank and, during the further closing movement, the
forming operation is sometimes completed before the bottom dead
center is reached. By further lowering of the press, the contact
pressure via the compensating element and/or the spring is then
increased, thus ensuring optimum fitting of the formed blank in the
forming cavity. The bottom dead center position can then be
particularly effectively maintained while the quenching operation
for press hardening is carried out since a particularly
advantageous conduction of heat is ensured because of the contact
with increased surface pressure of formed blank with the inner side
of the respective forming tool halves of the hot-forming and
press-hardening tools. During the press-hardening time, the contact
heating can then take place simultaneously at the contact heating
tools. It is also possible to configure the springs or compensating
elements of the contact heating tools in such a manner that the
contact heating tools have reached full contact of the blanks to be
heated without the press already being at the bottom dead center. A
further closing of the press then ensures that the contact pressure
of the contact heating tools with the blank to be heated is
increased, which has a positive influence on the transfer of heat
because of heat conduction owing to the increased surface pressure
and the thus improved contact.
[0017] The relative mounting can be designed as described
below.
[0018] The contact heating tools and the hot-forming and
press-hardening tools can each be mounted in a floating manner
individually or together on the top die or on the bottom die by
means of a hydraulic compensating cushion. In the event of
individual mounting, each tool part, consequently each contact
heating tool and each hot-forming and press-hardening tool, is then
assigned to a compensating cushion on the top die and/or on the
bottom die. In the event of a combined mounting, it is possible,
for example, for the two contact heating tools to be mounted via a
common compensating cushion and for the two hot-forming and
press-hardening tools each to be mounted on the top die and/or
bottom die likewise via a common compensating cushion. All of the
tools can also be mounted on the top die and/or on the bottom die
of the press via a respective central common cushion. The mounting
takes place in a floating manner such that a relative movement with
respect to the press stroke direction in a translatory and/or
rotatory manner is possible. The hydraulic compensating cushion is
designed in such a manner that a cushion cover, in particular a
metallic cushion cover, is formed between the rear side or back
side of the respective tool and punch of the top die and/or press
table of the bottom die. Said cushion cover is then filled with a
hydraulic medium, in particular a fluid. The pressure in the
hydraulic cushion can be preset here or else is actively
readjustable or settable as the closing movement is being carried
out and/or in the closed state.
[0019] If the press is now closed, the contact heating tools and/or
the hot-forming and press-hardening tools can carry out a relative
compensating movement with the press closed, and therefore tilting
is eliminated by means of the floating mounting with the hydraulic
compensating cushion, and the contact heating tools and hot-forming
and press-hardening tools, which are each suspended on the top die
and bottom die of the press, can be optimally aligned with one
another, and the press force can be transmitted to the blanks to be
heated and/or to the formed blanks and can therefore ensure a
uniform contact. The compensating cushion itself is designed in
such a manner that it withstands the compressive forces occurring
during the pressing.
[0020] In particular, the advantage is afforded here that sliding
blocks can be formed on the top die or on the punch of the top die
or on a press table of the bottom die, on which sliding blocks
contact heating tools and/or hot-forming and press-hardening tools,
which are interchangeable for changing over the production line,
are then mounted with the incorporation of the compensating
cushion. A simple change of tools can therefore take place and,
because of the floating mounting, a complicated readjustment or
remachining, in particular of the hot-forming and press-hardening
tools, can be dispensed with since a relative inherent centering
with respect to one another takes place because of the floating
mounting. For example, it is also conceivable for the compensating
cushion to be controlled actively and therefore for the pressure in
the compensating cushion to be increasable via a hydraulic
cylinder. When the press is completely closed, a high pressure can
therefore be introduced into the compensating cushion, as a result
of which the contact pressure at contact heating tool and/or the
hot-forming and press-hardening tools is increased,
[0021] In a further preferred variant embodiment of the mounting,
the contact heating tools and/or the hot-forming and
press-hardening tools are mounted in a manner so as to be
relatively movable on the top die and/or on the bottom die with the
incorporation of a plurality of spring elements. When the press is
closed, the contact heating tools and/or hot-forming and
press-hardening tools moving toward one another can therefore
execute a relative movement because of the spring elements, and
therefore a virtually complete contact is ensured for the contact
heating or for the contact cooling during press hardening. Also in
this case, it is possible, in turn, for the contact heating tools
and/or for the hot-forming and press-hardening tools to be mounted
in a floating manner on the top and/or on the bottom die of the
press, in particular via sliding blocks, such that, specifically
during a change of tools for changing of the production line to
other products, short set-up times arise and complicated
readjustment work is dispensed with. It is also possible for the
springs to be blockable.
[0022] Guides, in particular linear guides, are furthermore
particularly preferably provided such that, in the case of a
floating mounting of the contact heating tools and/or of the
hot-forming and press-hardening tools, centering transversely with
respect to the vertical direction takes place because of the linear
guide in the press closing direction, By this means, a lateral
unintentional offset of hot-forming and press-hardening tool and/or
of the contact heating tools is avoided,
[0023] In a further preferred variant refinement, the two
hot-forming and press-hardening tools are in each case designed as
combined hot-cutting and hot-perforating tools. The blanks can
therefore first of all be heated by the contact heating tools and
subsequently transferred into the hot-forming and press-hardening
tools by means of a conveyor. In the hot-forming and
press-hardening tools, the blanks can then be formed and trimmed
and/or perforated in the still hot state. After the forming
operation has finished, the formed components can then be
press-hardened by means of quenching. A further remachining can
then advantageously be dispensed with, as a result of which, in
turn, the production time and therefore the production costs are
lowered. Also, only a small amount of tool wear should be noted
here since the hot cutting or hot perforating is carried out on the
relatively soft, heated metal blank and not subsequently on the
already hardened motor vehicle component. Within the scope of the
present invention, the contact heating tools can be designed in
such a manner that they completely heat the blanks and in
particular completely heat the same up over the austenitizing
temperature.
[0024] However, it is also possible within the context of the
present invention for the contact heating tools to carry out only
partial temperings. Consequently, blank regions are not heated at
all or are heated lower than the AC3 temperature, whereas other
regions are heated up over the austenitizing temperature. It is
also conceivable within the context of the invention for the blanks
placed into the contact heating tools to be first of all preheated,
for example homogeneously to a temperature lower than or equal to
the AC1 temperature or a temperature lower than the AC3
temperature. In the contact heating tools, regions are then heated
up in a targeted manner above the AC3 temperature, whereas the
regions below the AC3 temperature are either kept at said
temperature or are not tempered at all, but also do not cool down
severely.
[0025] It is also conceivable within the context of the invention
for the hot-forming and press-hardening tools to be of segmented
design such that, for example in the case of the blank being heated
up completely homogeneously to over the AC3 temperature, a
partially different cooling takes place. It is also possible for a
partially different tempering to take place in the contact heating
tools and a partially different quench hardening to take place in
the hot-forming and press-hardening tools. By this means,
components can be produced with strength regions which are
partially different from one another.
[0026] Within the context of the present invention, it is also
conceivable for the contact heating tools and/or the hot-forming
and press-hardening tools to be of segmented design in each case.
By means of the individual segments, regions which are partially
different from one another can then be tempered and/or quenched,
with only a low conduction of heat within the tool and the blank or
within the hot-formed and press-hardened component arising, in
particular through separating gaps between the segments. The
different segments of the contact heating tools and/or of the
hot-forming and press-hardening tools can also be formed from
materials which differ from one another, and therefore different
temperings take place because of the different heat conductivities
of each material.
[0027] Furthermore, a conveyor is provided which transfers the
heated blanks from the contact heating tools into the hot-forming
and press-hardening tools. The conveyor is designed in particular
as a linear conveyor which transfers the heated blanks within the
press into the hot-forming and press-hardening tools. The conveyor
is preferably designed as a rack drive or 2-axle or 3-axle drive.
However, the conveyor may also be designed in such a manner that it
already supplies the cold blanks to the contact heating tools and
removes the finished, hot-formed and press-hardened components from
the press. However, the supplying of the cold blanks and removal of
the components produced can also take place by means of a
respective manipulator, for example by means of an industrial
robot. A plurality of isochronously movable linear conveyors which
are arranged one behind another in the conveying direction offset
by the width of a heating and/or press-hardening tool are also
possible.
[0028] The time required by the conveyor in order to transfer the
heated blanks from the contact heating tools into the hot-forming
and press-hardening tools is less than or equal to the press cycle,
preferably less than half the press cycle, and, in particular, the
time is less than one third of the press cycle. An opening movement
can be carried out until the top dead center is reached and at the
same time, in turn, then a closing movement of the press, wherein,
for example, with the press already half or three quarters open,
the transport of the heated blanks to the hot-forming and
press-hardening tools begins, the press reaches the top dead center
and, in turn, carries out the closing movement. Before the middle
closing distance is reached, the conveyor has already placed the
heated blanks into the hot-forming and press-hardening tools. This
affords the advantage according to the present invention of
rationalizing the production time, in particular if the contact
heating already begins because of contact before the bottom dead
center is reached. The same is true for the hot-forming and
press-hardening tool. In so far as the forming is already finished
before the bottom dead center is reached, the press hardening can
already start. By means of the two previously described measures,
the time for keeping the press closed is in turn reduced,
preferably to zero, and therefore so is the production time as a
whole.
[0029] A servopress or else a hydraulic press is particularly
preferably used as the press itself. The two presses permit, in
particular, the targeted control possibility with regard to opening
and closing movements and, in the closed position, permit the
contact pressure to be readjusted once again, and therefore it is
possible to meet the contact heating requirements and the
hot-forming and press-hardening requirements simultaneously in one
press.
[0030] In a further preferred variant refinement, the contact
heating tool is designed in such a manner that the latter has at
least one contact plate, preferably two contact plates,
consequently one contact plate on the top die and one on the bottom
die, which then enclose a blank between them when the press is
closed. The at least one contact plate is preferably heatable by
induction.
[0031] In an alternative variant refinement, it is also possible
for the contact plate itself to be designed as a conductor, wherein
the conductor is heated on the basis of electrical resistance
heating when a current is conducted therethrough, wherein the
current flow is interrupted before contact with the blank in order
to avoid a short circuit. The contact of the heated conductor then
in turn ensures that heat is transferred from conductor to the
blank to be heated.
[0032] Within the context of the present invention, it is also
possible to use segmented contact plates such that regions of the
blank which partially differ from one another are heated in a
targeted manner.
[0033] In the event of the use of a conductor, a flat conductor is
preferably formed, the conductor having one and/or more gaps,
wherein the parts which are separated by the slot or gap then
produce a conductor or a current path through which an electric
current then flows when the poles are connected and heats the
conductor in the process. It is also conceivable to form a contact
plate by means of a plurality of conductors, wherein the individual
conductors are then in each case tempered differently from one
another such that regions differing from one another are formed in
the blank. In order to avoid an electrical short circuit, the
current flow is then interrupted in each case at the latest shortly
before contact with the blank. The remaining heat is then output by
means of heat conduction.
[0034] It is also possible to heat the contact plates by other heat
sources, for example by heat radiation or other heat conduction.
Preferably, however, in the case of contact plates, the latter are
heated via an inductor. The contact plates themselves then in turn
output the sensible heat by means of heat conduction to the blank
to be heated.
[0035] In a further preferred variant refinement, the contact
heating tool is designed in such a manner that an electric
compensating element is formed. A current-conducting
cross-sectional area is formed, and therefore the one contact
heating tool is designed as an electric compensating element. The
latter is placed onto the blank to be heated, with the
current-conducting cross-sectional area of the compensating element
added to the current-conducting cross-sectional area of the blank
to be heated then forming an overall current-conducting
cross-sectional area, wherein, by configuration of the overall
current-conducting cross-sectional area, a homogeneous heating of
the blank takes place or a partially differing heating takes place
in a targeted manner. The contact heating tool is formed here as a
combined heating tool from heat transferring and from the
compensating element by means of heat conduction because of contact
and heat produced directly in the blank because of an electrical
current flow. In particular, a varying width and/or thickness of a
previously trimmed blank can be compensated for in a targeted
manner with the electric compensating element, and/or by varying
the current cross-sectional area of the compensating element
itself, a more substantial influencing of the heating in the blank
can be brought about in a targeted manner, in particular with a
homogeneous cross-sectional profile because of the conduction of
electrical energy.
[0036] In a further preferred variant refinement, either the
contact heating tools themselves or alternatively also the
hot-forming and press-hardening tools can each have an additional
trimming tool and/or perforating tool. It is thereby possible to
integrate cutting out operations and/or edge trimming into the
production process.
[0037] In a further advantageous variant refinement, an elastic
adjusting element is arranged between the hot-forming and
press-hardening tool and the press or the top die or bottom die of
the press, as a result of which the hot forming is already
completed before the press is completely closed, and the residual
closing distance of the press leads to compression of the elastic
adjusting element. It is also conceivable to arrange such an
elastic adjusting element between press and contact heating tools.
It is preferable that a plurality of elastic adjusting elements be
usable per tool. This means that the hot forming is completed and
keeping the press shut begins before the press itself reaches the
bottom dead center or reversing point. Furthermore, keeping the
press shut is ended only upon the upward movement thereof after the
latter has completely traversed the bottom reversing point or the
bottom dead center and the top die is in turn raised. By means of
this measure, the cycle time of hot forming and press hardening of
the sheet-metal component is in turn reduced in such a manner in
that the forming already begins at a very early point and is
completed before the other dead center is reached, and the holding
time is maximally used for the quenching hardening of the formed
sheet-metal component.
[0038] As a positive secondary effect, the adjusting elements,
which are in turn elastic, can be used for compensating for tilted
contact heating tools and/or hot-forming and press-hardening tools.
At the same time, differences in the press dropping together
between contact heating tool and hot-forming and press-hardening
tool because of different required press forces can be compensated
for with the elastic adjusting elements. The elastic adjusting
elements are decisively designed as passive adjusting elements, in
particular as compression springs. However, the elastic adjusting
elements may also be, for example, of active design by means of an
electric, hydraulic or pneumatic actuator. The advantage arising
therewith is that the time for keeping the press closed at the
bottom dead center can be reduced to zero.
[0039] Furthermore, an elastic element is particularly preferably
incorporated between contact heating tool and press table, wherein
the elastic element compensates for a thermal expansion of the
contact heating tool, in particular of a segment of a segmented
contact heating tool. Precisely in the case of partially differing
contact heating in conjunction with a segmented contact heating
tool, the individual elements expand to different degrees from one
another because of thermal action. Due to the different
temperatures and/or different coefficients of thermal expansion,
individual segments expand to differing degrees from one another.
Even the deviation of a few tenths of a millimeter may already
partially lead to no more contact with the blank to be heated, and
therefore poorer heating and/or heating which is not clearly
demarcated is carried out.
[0040] By means of the elastic elements on the contact heating
tools, in particular on the segments of the contact heating tools,
the present invention is able to compensate for thermal expansions
which differ from one another.
[0041] The previously mentioned object is furthermore achieved
according to the present invention by a method for producing
hot-formed and press-hardened motor vehicle components using a
two-blow heating and forming tool according to the previously
mentioned features in that two mirror-inverted motor vehicle
components are produced simultaneously in one press cycle. Two
blanks are likewise heated and are machined by forming in the
following press cycle.
[0042] It is therefore possible in particular for left/right
components, for example a left B pillar and a right B pillar with
respect to the direction of travel, to be produced. The advantage
is in particular afforded here of shortening the production time
and using effects of synergy since it is not necessary for four
individual heating and forming devices to be operated, but rather
all of the components can be produced simultaneously on one
press.
[0043] Within the context of the invention, it is possible in
particular to carry out the heating on the contact heating tool in
a time of 3 to 20 seconds, in particular 4 to 10 seconds. The
forming is carried out isochronously in a time of preferably 0.1 to
3 seconds, in particular 1 to 2 seconds, wherein the quench
hardening is carried out directly following the forming in a time
of 4 to 20 seconds, particularly preferably of 5 to 10 seconds.
BRIEF DESCRIPTION OF THE DRAWINGS
[0044] Further advantages, features, properties and aspects of the
present invention are the subject matter of the description below.
Preferred variant refinements are illustrated in the schematic
figures as summarized below.
[0045] FIG. 1 shows the two-blow heating and forming tool according
to the present invention in a side view.
[0046] FIG. 2 shows the tool from FIG. 1 with additional
compensating elements.
[0047] FIG. 3 shows a cross-sectional view through a hot-forming
and press-hardening tool with resilient mounting.
[0048] FIG. 4 shows an alternative variant in a partial sectional
view.
[0049] FIG. 5 shows a schematic top view of the heating and forming
tool according to the invention.
[0050] FIG. 6 shows a contact plate designed as conductor, in a top
view.
[0051] FIG. 7 shows a cross section through a contact heating tool
according to the invention with compensating element.
[0052] FIG. 8 shows a variant refinement of the heating and forming
tool according to the invention in a detailed view with respect to
the hot-forming and press-hardening tools.
[0053] FIG. 9 shows a cross-sectional view of a contact heating
tool according to the invention.
[0054] FIG. 10 shows an exemplary embodiment of a three-blow
tool.
[0055] FIG. 11 shows an exemplary embodiment of a four-blow
tool.
[0056] FIGS. 12 to 14 show the process sequence of a hot-forming
line according to the invention with a combined heating and forming
tool.
[0057] FIGS. 15a and b show a raising function of a linear conveyor
system with fixed gripping elements.
[0058] FIGS. 16a and b show a raising function of a linear conveyor
system with relatively movable gripping elements.
[0059] FIGS. 17a to c show active grippers according to the
invention.
[0060] In the drawing figures, the same reference signs are used
for identical or similar components, even if a repeated description
is omitted for reasons of simplicity.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0061] Further scope of applicability of the present invention will
become apparent from the detailed description given hereinafter.
However, it should be understood that the detailed description and
specific examples, while indicating preferred embodiments of the
invention, are given by way of illustration only, since various
changes and modifications within the spirit and scope of the
invention will become apparent to those skilled in the art from
this detailed description.
[0062] FIG. 1 shows the two-blow heating and forming tool 1
according to the invention in a side view. The heating and forming
tool 1 has a central press 2, wherein two contact heating tools 3
and, following the latter, two hot-forming and press-hardening
tools 4 are arranged within the press 2. Blanks 5 from a stack of
blanks are placed into the heating and forming tool 1, and heated
and pre-shaped to form motor vehicle components 6 and
press-hardened. According to the present invention, two motor
vehicle components 6 are simultaneously produced with the two-blow
heating and forming tool. Two blanks 5 are placed into the contact
heating tools 3. The blanks 5 which are located to this point in
the contact heating tools 3 and which have been heated are both
simultaneously transferred by a conveyor 7, illustrated here as a
linear conveyor, into the hot-forming and press-hardening tools 4.
When the press 2 of the heating and forming tool 1 is closed, the
two blanks 5 placed into the contact heating tools 3 are therefore
heated, and the heated blanks transferred into the hot-forming and
press-hardening tools 4 are formed to give a respective motor
vehicle component 6.
[0063] The distance to be covered between contact heating tool 3
and hot-forming and press-hardening tool 4 is constant for each
blank 5, and therefore a uniform temperature drop arises in each
component because of the transfer time.
[0064] The hot-forming and press-hardening tools 4 can be
additionally designed as hot-perforating and/or hot-cutting tools,
and therefore perforating and/or trimming is also carried out
simultaneously with the forming.
[0065] FIG. 2 shows the two-blow heating and forming tool 1 from
FIG. 1 with additionally arranged spring bearings 8. In this
variant refinement, the hot-forming and press-hardening tools 4 and
the contact heating tools 3 are mounted resiliently. This affords
the advantage that, when the press 2 is closed by upper part 9 and
lower part 10 of the contact heating tools 3 and/or upper part 11
and lower part 12 of the hot-forming and press-hardening tools 4
relative movements can be compensated for via the spring bearings
8. This relates in particular to thermally different expansions,
but also to distortion which may occur between the top die 13 and
the bottom die 14 during operation of the press 2,
[0066] FIG. 3 shows a cutout of the press 2 according to the
invention with respect to a hot-forming and press-hardening tool 4
with upper part 11 and lower part 12. Moreover, the upper part 11
of the hot-forming and press-hardening tool 4 is mounted on the top
die 13 and the lower part 12 of the hot-forming and press-hardening
tool 4 is mounted on the bottom die 14, more precisely on a press
table 15 of the bottom die 14. For this purpose, the hot-forming
and press-hardening tool 4 firstly has cooling ducts 16 and
secondly a forming cavity 17 is produced between a forming surface
18 of the upper part 11 and a forming surface 19 of the lower part
12 of the hot-forming and press-hardening tool 4. As illustrated
here, it is possible by means of tilting, in particular by means of
rotation with respect to the press stroke direction 20, for an
erroneous position of the upper part 11 and lower part 12 of the
hot-forming and press-hardening tool 4 to occur. To compensate for
said erroneous position, spring elements 21 are arranged between
press table 15 and lower part 12 of the hot-forming and
press-hardening tool 4, said spring elements, upon further carrying
out of the closing movement, compensating for the position of the
lower part 12 of the hot-forming and press-hardening tool 4 in such
a manner that an approximately uniform contact of the formed blank
5 (not illustrated specifically) and the respective forming surface
18 of the hot-forming and press-hardening tool 4 occurs in the
forming cavity 17. By means of the virtually complete contact, very
good removal of heat is noted. Also illustrated is a control line
22 via which, for example, the spring elements 21 would be
blockable. The spring elements 21 themselves may be designed as
mechanical springs, in particular spiral springs or helical
compression springs, but also as hydraulic or pneumatic spring
elements.
[0067] FIG. 4 shows an alternative variant of the hot-forming and
press-hardening tool 4 in a partial sectional view, wherein a
hydraulic cushion 23 is arranged here between top die 13 and upper
part 11 of the hot-forming and press-hardening tool 4. For this
purpose, the hydraulic cushion 23 has a cushion cover 24 which is
coupled in a fluid-tight manner to the top die 13 of the press 2 at
a frame 25 encircling the outside. A corresponding fluid is then
arranged in an arising interior space 26, and therefore the upper
part 11 of the hot-forming and press-hardening tool 4 can move
relative to the top die 13 of the press 2. In order to basicly
ensure contact and transition of the entire press force in the
press stroke direction 20, contact bars 27 are furthermore
arranged, and therefore, in the event of reaching the bottom dead
center of the press 2, a backside 28 of the upper part 11 of the
hot-forming and press-hardening tool 4 comes into form-fitting
contact with the top die 13 of the press 2 because of the contact
bar 27 and therefore at the latest then transmits the entire press
force. However, it is possible beforehand to ensure optimum
self-centering of upper part 11 and lower part (not illustrated
specifically) of the hot-forming and press-hardening tool 4 by
carrying out the relative movement because of the hydraulic cushion
23.
[0068] The respective floating mounting of FIG. 3 or FIG. 4 is
alternatively or additionally also applicable to the contact
heating tools 3.
[0069] FIG. 5 shows a schematic top view of the heating and forming
tool 1. A conveyor 7 in the form of a linear conveyor 29 is
illustrated. After heating, the blanks 5 are transferred in the
conveying direction 30 to the press-hardening tools (not
illustrated specifically). For this purpose, the conveyor 29 is
provided with receptacles 31 which then grasp the blanks 5 by means
of a contact or gripping device (not illustrated specifically) and
convey said blanks in the conveying direction 30. It is furthermore
illustrated that a left region of the blank 5 with respect to the
plane of the figure is heated to a temperature of AC1 and a region
of the blank 5 with respect to the right plane of the figure is
heated to a temperature of AC3. Consequently, temperature regions
which are different from one another are produced on the blanks 5
and then, after the press-hardening operation is completed, said
temperature regions produce two regions 33, 34 which are different
from each other on the motor vehicle components 32 produced,
wherein a first region 33 has a lower strength than a second region
34. The two motor vehicle components 32 produced can then be, for
example, a left B pillar and a right B pillar for a motor vehicle
body, said B pillars being produced simultaneously in one press
cycle.
[0070] FIG. 6 shows a contact plate 35 designed as a conductor, in
a top view. The contact plate 35 itself has a rectangular
configuration, wherein various slots 36 which extend from an upper
side as far as a lower side of the contact plate 35, with respect
to into the direction of the figure, are formed within the contact
plate 35. By this means, the contact plate 35 is separated
electrically from the slots 36 in such a manner that a current path
37 is produced through the contact plate 35. If two electric poles
38 are then connected and a current is applied to the contact plate
35, an electric current flows through the current path 37 and heats
the contact plate 35 because of resistance heating. When the
closing movement is being carried out and/or a blank 5 to be heated
is deposited on the contact plate 35, the current flow is
interrupted shortly before the surface contact in order to avoid an
electrical short circuit. The heat located in the contact plate 35
is then output to the blank to be heated because of contact by the
contact plate 35.
[0071] FIG. 7 shows a cross section through a contact heating tool
3 according to the invention. It is readily apparent here that,
firstly, the blank 5 to be heated has been inserted, but a
compensating element 39 is arranged on the upper part 9 of the
contact heating tool 3. Electric poles 38 are arranged in each case
on the outer side of the compensating element 39, and therefore,
when in the state of a closed contact heating tool 3, in particular
with contact, preferably electrical, conductive contact, of
compensating element 39 and blank 5 and application of an electric
current, a resistance heating both of the compensating element 39
and optionally of the blank 5 is produced. At the same time,
however, the compensating element 39 has a residual heat, and
therefore, in addition, by means of heat conduction, an application
of heat to the blank 5 to be heated likewise takes place because of
the contact. It can be seen that, in the transverse direction Q,
the compensating element 39 has a differing cross-sectional area,
wherein the entire compensating element 39 is formed from a
conductive material. The differing cross-sectional area results in
a differing current-conducting cross-sectional area and therefore
in heating, which partially differs in intensity, because of the
current flow density. In particular, more intense heating arises at
the left and right end, at both of which a smaller cross section
should be noted, than in a central region because of a higher
current flow density. Owing to the fact that the blank 5 has a
constant cross section, firstly, when a current is applied to the
electric poles 38, more current flows in the outer regions through
the blank 5, and therefore more intense heating can be noted here.
The current-conducting cross-sectional area of the compensating
element 39 and the current-conducting cross-sectional area of the
blank 5 then produce an overall current-conducting cross-sectional
area. Also illustrated is an insulating counterlayer 40 on the
lower part 10 of the contact heating tool 3 and also an insulating
counterlayer 40 between upper part 9 of the contact heating tool 3
and the compensating element 39.
[0072] FIG. 8 furthermore shows a variant refinement of the heating
and forming tool 1 according to the invention in a detailed view
with respect to the hot-forming and press-hardening tools 4. It is
illustrated here in turn that the upper part 11 and the lower part
12 of the respective hot-forming and press-hardening tool 4 are
arranged on the top die 13 and the bottom die 14, respectively, of
the press 2. The lower parts 12 of the hot-forming and
press-hardening tool 4 are mounted here spaced apart at a distance
a from a press table 15 of the bottom die 14 in the press stroke
direction 20. When the closing movement is carried out, the upper
part 11 and the lower part 12 of the respective hot-forming and
press-hardening tool 4 therefore already come into contact,
incorporating the blank 5, and therefore the forming operation is
completed even before the bottom dead center is reached. A further
lowering then leads to compression of the respective elastic
adjusting element 41, and therefore the lower parts 12 of the
hot-forming and press-hardening tools 4 move in the direction of
the press table 15 of the bottom die 14. During this period of
time, the press-hardening operation can already begin because of
the cooling ducts 16, and it is ensured in turn that a virtually
full contact of upper tool 11 with the formed blank 5 and lower
part 12 and formed blank 5 of the hot-forming and press-hardening
tool 4 and associated good heat conduction are produced.
Furthermore, there are centering means 42 in the form of centering
pins which are formed protruding in relation to the lower parts 12
of the hot-forming and press-hardening tools 4 and come into
engagement with centering grooves 43 formed on the upper parts 11
of the hot-forming and press-hardening tools 4 when the closing
movement is carried out in the press stroke direction 20. By this
means, a linear guidance is performed in the press stroke direction
20, said guidance in particular avoiding a lateral offset of upper
part 11 and lower part 12 of the hot-forming and press-hardening
tool 4 specifically because of the elastic mounting by means of the
adjusting elements 41, This design can also be implemented on the
contact heating tools 3.
[0073] FIG. 9 shows a cross-sectional view of a contact heating
tool 3 according to the invention, wherein the contact heating tool
3 has a plurality of individual segments 44, 45. The segments 44
here are in particular non-tempered segments and the segments 45,
by contrast, are actively heated segments tempered to a higher
temperature in relation to the temperature of the segments 44. All
of the segments 44, 45 are formed in a manner thermally insulated
from one another via a respective separating gap 46. Consequently,
the actively heated segments 45 expand more greatly than the
segments 44, and therefore it is provided according to the
invention that elastic elements 47 are arranged on the lower
segment 45 in a manner suspended on the press table 15 of the
bottom die 14 such that a thermal expansion, in particular in the
press stroke direction 20, is compensated for by the elastic
elements 47. Within the context of the invention, each individual
segment 44, 45 of the contact heating tool 3 can therefore also be
mounted on its own per se, in particular in a manner so as to be
relatively movable by means of elastic elements 47, and therefore a
differing thermal expansion is compensated for by the elastic
elements 47 and hence the individual segments 44, 45 are each
approximately in contact over the full area thereof with the blank
5 to be heated. This variant refinement may also be transferred to
the hot-forming and press-hardening tool 4. Furthermore, a linear
guide 48 is provided which permits linear guidance in the press
stroke direction 20 and reduces shearing off transversely with
respect to the press stroke direction.
[0074] FIG. 10 shows a top view of a combined heating and forming
tool 1 according to the invention which is of three-blow design.
For this purpose, individual blanks 5 are placed in the conveying
direction 30 into the heating and forming tool 1 and first of all
three blanks 5.1 are simultaneously heated on one contact heating
tool 3 each and, in the subsequent press cycle, the three heated
blanks 5.2 are simultaneously formed in three hot-forming and
press-hardening tools 4 such that three motor vehicle components 6
are produced simultaneously in one press cycle. In this case, a
three-blow heating and forming tool 1 is described.
[0075] FIG. 11 shows a variant refinement of the heating and
forming tool 1 according to the invention as a four-blow variant.
In this case, blanks 5 from two stacks of blanks are first of all
again placed in the conveying direction 30 into the heating and
forming tool 1. However, there are now only two contact heating
tools 3 here, wherein each contact heating tool simultaneously
heats two blanks 5.1 to be heated. Each heated blank 5.2 is then
brought onto a separate hot-forming and press-hardening tool 4,
and, during a press closing movement, consequently a press cycle,
four motor vehicle components 6 are simultaneously produced. These
are in particular smaller motor vehicle components 6, for example
reinforcing patches or the like. In this case, the heating and
forming tool 1 is of four-blow design. It is also conceivable for
the contact heating tools 3 to be arranged next to one another in
the conveying direction 30 and also for the four hot-forming and
press-hardening tools 4 to be arranged next to one another in the
conveying direction 30.
[0076] FIG. 12 shows a heating and forming tool 1 according to the
invention, having a contact heating tool 3 and a hot-forming and
press-hardening tool 4 and also a linear conveyor system 49
arranged thereon. The contact heating tool 3 is a two-blow tool.
This means, two blanks 5.1, 5.2 can be simultaneously heated in one
contact heating tool 3. The hot-forming and press-hardening tool 4
is likewise a two-blow tool. This means, two heated blanks are
simultaneously hot-formed and subsequently press-hardened in one
hot-forming and press-hardening tool 4. The gripping elements are
preferably designed as blank grippers 51 and/or tempering grippers
52 and/or product grippers 53. The linear conveyor system 49 has
two rails 50 arranged parallel to each other, wherein gripping
elements are arranged on the rails 50. Two blank grippers 51 are
arranged from the left to the right, with respect to the plane of
the figure. Two tempering grippers 52 are arranged in the center,
with respect to the plane of the figure, and two product grippers
53 are arranged on the right side, with respect to the plane of the
figure. The heating and forming tool 1 is therefore a two-blow
tool. It can also be of single-blow, three-blow, four-blow or
multi-blow design. Furthermore, an overall displacement distance G
is illustrated.
[0077] According to the variant illustrated here, the gripping
elements are positionally fixed with respect to the rails 50 in the
axial direction 54 of the rails 50, wherein the rails 50 are
movable in the axial direction 54 thereof. Alternatively, it would
also be conceivable for the gripping elements to be shiftable in
the axial direction 54 with respect to the rails 50.
[0078] Furthermore, it is illustrated that the rails 50 have
carried out a relative movement 55 with respect to the axial
direction 54 thereof orthogonally inward. The respective gripping
elements have therefore been brought into engagement with the
blanks 5.1, the heated blanks 5.2 or motor vehicle components
6.
[0079] The linear conveyor system 49 then carries out a transport
movement in the axial direction 54 of the rails 50. The end
position is illustrated in FIG. 13. The formed motor vehicle
components 6 are deposited on a schematically illustrated
depositing stack 56. The heated sheet-metal blanks 5.2 are
deposited on the hot-forming and press-hardening tool 4. The newly
received sheet-metal blanks 5.1 are deposited on the contact
heating tool 3, and, in turn, new sheet-metal blanks 5.1 are ready
for heating. Subsequently, a movement is carried out outward by the
rails 50, and therefore the entire rails 50 with the respective
gripping elements are moved outward with respect to the axial
direction 54 of the rails 50 and are no longer in engagement with
the sheet-metal blanks 5.1, 5.2 and motor vehicle components 6.
[0080] A reversing movement 57 is then carried out in the axial
direction 54 of the rails 50, in particular said reversing movement
57 is carried out synchronously with the two rails 50, as shown in
FIG. 14. Subsequently, the operation begins again, as illustrated
in FIG. 12. The returned rails 50 are moved toward each other, and
therefore the gripping elements come into engagement with the
heated sheet-metal blanks 5.2 and the motor vehicle components
6.
[0081] FIGS. 15a and 15b show a raising operation of the blanks
with the blank grippers 51. The rails 50 have carried out a
relative movement 55 toward each other orthogonally with respect to
the axial direction 54 thereof, and therefore the blank grippers 51
are located below the sheet-metal blank 5.1 with respect to the
vertical direction V. Subsequently, a raising movement, illustrated
in FIG. 15b, is carried out by the rails 50. This means that the
entire rails 50 are moved upward in the vertical direction V. The
sheet-metal blank 5.1 then rests, as it were, on the blank grippers
51 and is likewise raised.
[0082] FIGS. 16a and 16b show an alternative variant refinement
thereto. Here, it is not the rails 50 which are raised with respect
to the vertical direction V, but rather only the blank grippers 51.
The latter are therefore mounted in a manner so as to be relatively
movable on the rails 50 with respect to the vertical direction and
can also be raised or lowered.
[0083] FIGS. 17a, 17b and 17c show a relative movement analogous to
FIGS. 16a and 16b, with the difference that the blank grippers 51
here are depicted as active grippers. The latter are illustrated in
an open position according to FIG. 17a, and therefore the rails 50
have carried out a relative movement 55 directed toward each other.
According to FIG. 17b, the blank grippers 51 as active grippers are
then closed and, according to FIG. 17c, are raised again in the
vertical direction V.
[0084] The invention being thus described, it will be apparent that
the same may be varied in many ways. Such variations are not to be
regarded as a departure from the spirit and scope of the invention,
and all such modifications as would be recognized by one skilled in
the art are intended to be included within the scope of the
following claims.
REFERENCE SIGNS
[0085] 1--heating and forming tool [0086] 2--press [0087]
3--contact heating tool [0088] 4--hot-forming and press-hardening
tool [0089] 5--blank [0090] 5.1--blank to be heated [0091]
5.2--heated blank [0092] 6--motor vehicle component [0093]
7--conveyor [0094] 8--spring bearing [0095] 9--upper part to 3
[0096] 10--lower part to 3 [0097] 11--upper part to 4 [0098]
12--lower part to 4 [0099] 13--top die to 2 [0100] 14--bottom die
to 2 [0101] 15--press table to 14 [0102] 16--cooling ducts [0103]
17--forming cavity [0104] 18--forming surface to 11 [0105]
19--forming surface to 12 [0106] 20--press stroke direction [0107]
21--spring element [0108] 22--control line [0109] 23--hydraulic
cushion 24--cushion cover [0110] 25--frame [0111] 26--interior
space [0112] 27--contact bar [0113] 28--backside to 11 [0114]
29--linear conveyor [0115] 30--conveying direction [0116]
31--receptacle [0117] 32--motor vehicle component [0118] 33--first
region to 32 [0119] 34--second region to 32 [0120] 35--contact
plate [0121] 36--slot [0122] 37--current path [0123] 38--electric
pole [0124] 39--compensating element [0125] 40--insulating
counterlayer [0126] 41--adjusting element [0127] 42--centering
means [0128] 43--centering grooves [0129] 44--segment [0130]
45--segment [0131] 46--separating gap [0132] 47--elastic elements
[0133] 48--linear guide [0134] 49--linear conveyor system [0135]
50--rails [0136] 51--blank gripper [0137] 52--tempering gripper
[0138] 53--product gripper [0139] 54--axial direction [0140]
55--relative movement [0141] 56--depositing stack [0142]
57--reversing movement [0143] a--distance [0144] G--overall
displacement distance [0145] Q--transverse direction [0146]
V--vertical direction
* * * * *