Specification
1
GS/jo 031247WO
ANNEALING RACK
Description
The present invention relates to an annealing rack,
particularly for transporting aluminum cast parts in the
heat treatment process.
Annealing racks for transporting annealing stock through
an annealing furnace and also for quenching the annealing
stock in quenching liquid are subjected to large
temperature variations and local temperature
differentials, so that they suffer large thermal
tensions. When an annealing rack filled with annealing
stock enters a furnace, the upper edge of the annealing
rack heats up first, while the side walls and the floor
are initially kept cold by the annealing stock. Due to
the varying heating, warping and fractures of the
annealing rack occur.
A method for annealing and internal rinsing of copper
pipe coils, the copper pipe coils being positioned in
annealing racks stacked one on top of another as they
pass through an annealing furnace, is known from DE 198
304 85 A 1. The stacking and unstacking of the annealing
racks is possible completely automatically. Detachable
connections between individual parts of the annealing
racks are not cited. With permanent connections, the
danger exists of permanent bending, and in the worst case
even a fracture. Securing the annealing product in the
annealing rack is not provided. If the annealing rack
bends, the annealing stock may thus shift or even tip
over.
-2-
A transport basket for annealing stock in roller hearth
furnaces, having a multipart floor made of multiple
lattice grates lying next to one another, which are
connected to one another in an articulated way having
slight angular mobility through bolts, and having front
and side walls which are connected permanently to the
floor and are connected to one another with expansion
mobility through profile clamps, is known from DE 344 45
07 C2. This transport basket is laid directly on the
hearth rollers and is carried along by them.
In this case, the disadvantage is that the annealing
stock may shift or tip over in such transport baskets
during transport and may thus incur damage. The side
plates are permanently connected to the lattice grates,
particularly welded. Permanent bending and possibly even
fracture may occur in this region. This may also cause
shifting or tipping over of the annealing stock.
Transport baskets bent in this way may not be stacked.
Such stacking is also not provided.
The present invention is therefore based on the object of
designing an annealing rack of the type cited, for the
transport of aluminum cast parts in the heat treatment
process in particular, in such a way that annealing stock
of greatly varying forms is secured therein so it is safe
from tipping and slipping during the conveyance.
The object is achieved in an annealing rack of the type
cited at the beginning in that it is constructed from at
least one annealing rack element having at least one
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annealing basket, which may be placed therein and is
adaptable to the annealing stock.
By dividing the annealing rack into annealing rack
element(s) and, in addition, annealing basket (s), stock
to be annealed may be placed securely in the annealing
basket in a simple way and may then be placed with this
basket in the annealing rack element. With heavier stock,
the basket is first placed in the annealing rack element
and subsequently filled. In additionally, using two or
more annealing baskets per annealing rack element is also
conceivable.
The above-mentioned division allows the annealing rack
element to be produced from very stable material in a
simple basic shape. The annealing baskets are then to be
designed individually for the particular stock to be
transported for secure transport while avoiding shifting
or tipping over of the annealing stock. A less stable
material may be selected for the baskets than for the
annealing rack elements. An annealing rack which is
assembled from multiple annealing rack elements may thus
receive annealing baskets of greatly varying design for
the secure transport of annealing stock of greatly
varying construction for simultaneous or sequential
annealing processes.
Preferred implementations are considered in the
subclaims.
The annealing rack according to the present invention may
be implemented in such a way that the annealing rack
elements are stackable one on top of another. The height
-4-
of the annealing rack may thus be oriented to the
quantity of the stock to be annealed.
Furthermore, the annealing rack according to the present
invention may be implemented in such a way that every
annealing rack element has at least one rest and corner
supports projecting upward from the corners of the rest.
A centering aid, particularly a cone-taper connection, is
conceivable for stacking the annealing rack elements, the
end of the corner supports distal from the rest surface
being provided as a cone and the end located on the
support being provided with a receiving taper. Secure
stacking and unstacking is thus made possible. In
addition, slipping and upsetting of the stacked annealing
rack elements in the event of dynamic loads during the
transport is prevented.
The floor may also be implemented in multiple parts, of
course. It may then be constructed depending on the space
required. The floor may have a closed surface, but
grating or frame floors are preferred. In this case,
perforated hollow profiles are preferably used for the
frames.
In a further embodiment, the corner supports may be
connected to the rest and/or to one another using rack
struts in at least one of the annealing rack elements.
The rack struts cause stabilization of the corner
supports and may prevent slipping of the annealing
basket. The rack struts may, for example, be flat steel.
In a further implementation of the annealing rack
according to the present invention, the rest, the corner
5
supports, and possibly the rack struts of the annealing
rack element are detachably connected to one another,
particularly by plug-in connections. Through the
detachable connections, all dynamic and thermal loads
arising during transport through the annealing furnace
may be absorbed without resulting in permanent
deformation. For this purpose, the connections are
preferably to be implemented having a slight play. After
the quenching in the water bath, there is no permanent
distortion of the annealing rack elements. The annealing
rack element according to the present invention is
therefore suitable for passing through the heat treatment
process frequently. The individual components may be
replaced easily. The storage costs are reduced, since the
annealing rack elements in the disassembled state and
individual replacement parts may be stored laid together
flat.
Furthermore, the annealing rack according to the present
invention may be implemented in such a way that at least
one of the annealing rack elements is provided with means
for detachable fixing of the annealing basket. In this
way, slipping of the annealing basket on the rest of the
annealing rack element, particularly in the event of
strong dynamic loads, is suppressed and/or reduced.
Depressions in the rest of the particular annealing rack
element, in which legs of the basket floor or the entire
floor surface of the annealing basket may be placed, are
particularly conceivable.
Furthermore, the annealing rack according to the present
invention may have an annealing basket in which the
basket floor is implemented having basket supports
6
projecting upward. The components to be annealed are
placed on the basket floor. The basket supports support
the components somewhat in this case. They may be
positioned on the basket floor as a function of the shape
and number of the components. The basket supports are
preferably hollow profiles, particularly perforated
hollow profiles. The basket floor may also be produced
from perforated hollow profiles and implemented as a
frame or grating, for example.
The annealing rack according to the present invention may
also have basket struts, the basket supports being
connected to the basket floor and/or to one another using
the basket struts in at least one of the annealing
baskets. In this case, the basket floor and the basket
supports and possibly the basket struts may be connected
to one another detachably, particularly by plug-in
connections. The connections of basket floor, basket
supports, and possibly basket struts are preferably to be
implemented having a slight play. Permanent distortion in
the heat treatment process is thus avoided. The basket
struts not only stabilize the basket supports, but rather
may additionally also support the components to be
annealed. In this case, they may also be attached at
different points as needed. The basket struts are
preferably produced from flat steel or perforated hollow
profiles.
Furthermore, in the annealing frame according to the
present invention, wire clips may be detachably attached
to the basket floor and/or the basket supports and/or the
basket struts. These wire clips may particularly be
plugged in and/or screwed in. These wire clips are ideal
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for especially complex aluminum components, as are used
in the automobile industry; for example. The individual
annealing stock may be removed"easily during the
automatic loading and unloading procedure, since it is
centered by the wire clips. In this case, the wire clips
may be plugged into prefabricated holes in the basket
floor and/or the basket supports and/or the basket
struts, and they may additionally be fixed using a nut
for security. The wire clips generally only assume a
centering function, while in contrast the remaining parts
of the annealing basket are to be implemented as more
stable. The annealing rack element is to be implemented
as the most robust.
Finally, in the annealing rack according to the present
invention, at least one of the annealing baskets may be
provided with means for detachable fixing on the
annealing rack. The annealing basket may thus be attached
to the annealing rack element and removed again easily.
The present invention will be.explained in greater detail
on the basis of the following exemplary embodiment.
Figure 1 shows a front view of an embodiment according
to the present invention of an annealing rack
element.
Figure 2 shows a side view of the annealing rack element
according to Figure 1.
Figure 3 shows a top view of the annealing rack element
according to Figure 1.
8
Figure 4 shows a front view of the annealing rack
element according to Figure 1 having inserted
annealing basket.
Figure 5 shows a side view of the annealing rack element
according to Figure 2 having inserted annealing
basket.
Figure 6 shows a top view of the annealing rack element
according to Figure 3 having inserted annealing
basket.
Figure 7 shows a detail view w of the plug-in
connections basket struts/basket supports of
the annealing basket.
Figure 8 shows a detail view x of the plug-in connection
of the rest profile/corner supports of the
annealing element.
Figure 9 shows a detail view y of the plug-in and screw
connection of the wire clip to the annealing
basket.
Figure 10 shows a detail view z of the plug-in connection
annealing rack element/annealing basket.
Figures 1-3 show an annealing rack element 1 in front
and side views and a top view.
The front view according to Figure 1 shows a short,
horizontal, hollow rest profile 2 as a part of the rest
3, which has multiple holes 4 and is connected via rack
- 9-
struts 5 to corner supports 6. All hollow profiles, i.e.,
annealing rack elements and baskets, used in the
annealing rack are preferably those having high
geometrical moments of inertia. In addition, preferably
all hollow profiles are selected having identical wall
thicknesses in order to avoid different temperature
profiles during the quenching procedure. Only some of the
holes 4 are provided with reference numbers.
Accelerations and inertial forces may be absorbed better
through the diagonally running rack struts 5. The corner
supports 6 are connected at their lower end to the rest 3
and have a centering tip 7 at their upper end. When
multiple annealing rack elements 1 are stacked one on top
of another, the centering tips 7 of the particular lower
annealing rack element 1 engage in corresponding recesses
of the rest 3 of the particular upper annealing rack
element 1. These recesses are not shown. The centering
aids 7 allow secure stacking and unstacking. In the event
of dynamic loads during the transport, slipping and
upsetting of the stacked annealing rack elements 1 is
prevented.
A transport switching flag 8 in the form of an oblong
sheet is positioned between two corner supports 6. This
transport switching flag 8 is also detachably attached
using bolts and cotter pin. It is detected by light
barriers (not shown) and the position of the annealing
rack is detected for the process controller on the basis
of this. For precise identification of an annealing rack,
an identification switching flag 17 is attached to one of
the corner supports 6, from which the details on each of
the individual annealing racks and/or the annealing stock
transported therein are readable. The function of the
- 10 -
positioning profile 9 illustrated is explained in the
following for Figure 3.
The side view shown in Figure 2 shows a long horizontal
rest profile 10 having holes 11 as a part of the rest 3,
as well as rack struts 5 and corner supports 6 having
centering aids 7. The long rest profile 10 has a greater
height than the short rest profile 2. Only some of the
holes 11 are provided with reference numbers.
In the top view shown in Figure 3, the construction of
the rest 3 having two short rest profiles 2 and two long
rest profiles 10 may be seen. Only some of the holes 4
and 11 are marked with reference numbers. Four corner
supports 6 having centering aids 7 are located in the
four corners of the rest 3. The long rest profiles 10 are
connected to one another via the positioning profile 9.
The positioning profile 9 has three square holes 12 . As
may be seen from Figures 5 and 10, the basket supports 18
are inserted into the square holes 12. More detailed
explanations in this regard are in the following
descriptions of the corresponding figures.
Figures 4 through 6 correspond to Figures 1 through 3.
They additionally have an annealing basket 13 which is
inserted into an annealing rack element 1. The basket
floor 14 comprises two short floor profiles 15, which are
positioned parallel and at a distance to one another and
between which four long floor profiles 16 are positioned.
The long floor profiles 16 lie on the shorter rest
profiles 2 and the positioning profile 9. In this case,
the positioning profile 9 is not only used for laying
down the annealing basket 13. The three square holes 12
- 11-
additionally allow the passage of three basket supports
18 of the annealing basket 13. These> basket supports 18
and the positioning profile 9 are implemented as hollow
profiles. The basket supports 18 are fixed solely by
gravity in the square holes 12. The annealing basket 13
may be raised easily out of the annealing rack element 1
after the heat treatment process. Upwardly projecting
basket supports 18 are positioned on the basket floor 14.
The basket supports 18 are connected to one another via
basket struts 19, the long basket struts 19 covering the
long floor profiles 16 in the top view shown in Figure 6.
Since the rest 3, the corner supports 6, and the rack
struts 5 of the annealing rack elements 1, and the basket
floor 14, the basket supports 18, and the basket struts
19 of the annealing basket 13 are all produced either
from multiply perforated hollow profiles of identical
wall thickness or from flat steel, the annealing stock
may be cooled rapidly and uniformly during the quenching
process. The flat steel cools down rapidly upon contact
with cold water and the coolant liquid, usually water,
may additionally penetrate extremely rapidly into the
hollow profiles through the multiple holes in the hollow
profiles. In this case, the selection of identical wall
thicknesses encourages uniform cooling.
The wire clip shown will be discussed in greater detail
in Figure 9.
Each part may be replaced individually as needed through
the plug-in connections and/or screw connections. No
complete annealing rack elements 1 have to be kept ready.
- 12 -
A small reserve is completely sufficient, this only-
occupying a small space in the disassembled state.
The detail w from Figure 6 is shown enlarged in Figure 7.
In this case, the plug-in connection of three parts of
the annealing basket 13 is shown. Using this plug-in
connection, a short floor profile 15 is detachably
connected to a long basket strut 19 running
perpendicularly thereto and, in addition, to a basket
support 18, which projects upward perpendicularly from
the basket floor 14.
For this purpose, the short floor profiles 15 have a
rectangular hole 20, into which the lower end of the
upwardly projecting basket support 18 is inserted with
play. This basket support 18 is drilled through above its
insertion region and the long basket strut 19 is inserted
through this hole with play. Therefore, this long basket
strut 19 lies on the short floor profile 15. The long
basket strut 19 is secured at its inserted end with play
using a cotter pin 21. The three parts of the annealing
basket are therefore equipped with a certain mobility in
the assembled state, through which the stability of the
basket is not negatively influenced and the basket may
manage tensions during the heat treatment and dynamic
loads well.
The detail x from Figure 1 is shown enlarged in Figure 8.
The plug-in connection of three parts of the annealing
rack element is recognizable here.
Using this plug-in connection, a long rest profile 10 is
detachably connected to a short rest profile 2 of the
-13-
rest 3 and to a corner support 6. In this case, each of
the three parts is oriented perpendicularly to each of
the two other parts.
The long rest profile 10 is implemented having a greater
height than the short rest profile 2. The long rest
profile 10 has a first hole 22, in which a short rest
profile 2 is inserted, in the region of one end, but at a
distance thereto on the side facing toward the interior
of the rest 3.
The long rest profile 10 has a second hole 23 in the
region of one end, but at a distance thereto. This second
hole 23 is applied to the upper face of the long rest
profile 10. The basket support 6 is inserted through this
second hole 23. Its lower end comes to rest on the short
rest profile 2, which is also inserted.
Two diametrically opposite retaining holes 24 and 24' are
positioned in the region of the lower end of the corner
support 6, but at a distance to this end. At the same
height, the long rest profile 10 also has a retaining
hole 25 and 25' on each side. The retaining holes 24, 24'
and 25, 25' in the long rest profile 10 and in the corner
supports 6 are positioned flush. A retaining bolt 26 is
inserted parallel to the longitudinal axis of the
inserted short rest profile 2 through these retaining
holes 24, 24', 25, and 25'. The retaining bolt 26 is
secured using a retaining cotter pin 27.
The strut bolt 28 having strut cotter pin 29 is used for
the purpose of detachably connecting a rack strut 5 to
the long rest profile 10 and the corner support 6.
- 14-
Through the retaining bolts 26 and strut bolts 28 having
assigned cotter pins 27 and 29, the rest profiles 2 and
10, the corner supports 6, and the rack struts 5 are
secured with play.
The detail y from Figure 6 is shown enlarged in Figure 9.
In this case, the plug-in and screw connections of wire
clips 30 to a long floor profile 16 of the basket floor
14 may be seen. In this case, the wire clips 30 shown are
inserted into or through holes of the long floor profiles
16. The wire clips 30 inserted through are screwed onto
the free ends of the wire clips 30 using self-locking
nuts 31. The wire clips 30 are specially shaped. They are
used for centering aluminum parts during the automatic
loading and unloading procedure. The wire clips 30 are
tailored to the particular aluminum component to be held.
The aluminum component is not shown.
The detail z from Figure 4 is shown enlarged in Figure
10. In this case, a plug-in connection for fixing an
annealing basket 13 on the annealing rack element 1 is
shown.
For this purpose, the positioning profile 9 of the
annealing rack element is provided with two diametrically
opposite square holes 12 on its top and bottom in such a
way that a basket support 1 of an annealing basket 13 may
be inserted through. In this case, the basket support 18
of the annealing basket 13 is implemented as a vertical
hollow profile, whose diameter is slightly smaller than
the diameter of the two holes 12. In the state inserted
through, regions of the basket floor 14 lie directly on
the upper side of the positioning profile 9.
-15-
The use of the low-distortion annealing rack according to
the present invention is to be explained in the following
on the basis of an example:
The annealing baskets are charged with the stock to be
treated, particularly aluminum cast parts for the
automobile field. The charging is typically performed
automatically. For this purpose, the baskets are already
in the annealing rack element or are raised therein after
charging. Baskets which are only self-supporting in the
empty state, but not with annealing stock inserted, are
generally used. Even annealing stock having very
complicated geometry may be fixed well by the wire clips.
The advantage of this division is that these baskets may
be adapted easily to the components and the simply
designed, stable annealing rack elements assume the
supporting function. After an automatic stacking of this
type of multiple annealing rack elements, the annealing
rack is introduced into the furnace via transport rollers
or transport chains. For this purpose, the annealing rack
has an at least largely planar bottom. The stock is now
annealed in the furnace. Subsequently, it is immersed in
a quenching basin which is filled with water, then
removed from the basin and made available for further
treatment. The individual treatment stages in the furnace
and subsequently in the quenching basin are automated in
such a way that automatic recognition units determine the
current position of the annealing rack and gripping units
may grip exactly. The annealing rack may also not have
any deformations, so that these positions may be detected
correctly.
- 16-
List of reference numbers
1 annealing rack element
2 short rest profile of the rest 3
3 rest of the annealing rack element 1
4 holes in the short rest profile 2
5 rack strut
6 corner support
7 centering tip
8 transport switching flag
9 positioning profile
10 long rest profile of the rest 3
11 holes in the long rest profile 10
12 square holes in the positioning profile 9
13 annealing basket
14 basket floor
15 short floor profiles
16 long floor profiles
17 identification switching flag
18 basket support
19 long basket strut
20 rectangular hole in the short floor profile 15
21 cotter pin for long floor profile 16
22 first hole in the long rest profile 10
23 second hole in the long rest profile 10
24 retaining hole in the corner support 6
24' retaining hole in the corner support 6
25 retaining hole in the long rest profile 10
25' retaining hole in the long rest profile 10
26 retaining bolt
27 retaining cotter pin
28 strut bolt
29 strut cotter pin
- 17 -
30 wire clip
31 nut
18
GS/jo 031247WO
Otto Junker GmbH, 52152 Simmerath, DE
Patent Application
Annealing rack
Patent Claims
1. An annealing rack, particularly for transporting
aluminum cast parts in the heat treatment process,
characterized in that it is constructed from at
least one annealing rack element (1) having at least
one annealing basket (13), which may be placed
therein and is adaptable to the annealing stock.
2. The annealing rack according to Claim 1,
characterized in that the annealing rack elements
(1) are implemented so they are stackable one on top
of another.
3. The annealing rack according to Claim 1 or 2,
characterized in that each annealing rack element
(1) has at least one rest (3) and corner supports
(6) projecting upward from the corners of the rest.
4. The annealing rack according to Claim 3,
characterized in that in at least one of the
annealing rack elements (1), the corner supports (6)
are connected to the rest (3) and/or to one another
using rack struts (5).
5. The annealing rack according to Claim 3 or 4,
- 19-
characterized in that the rest (3) , corner supports
(6), and possibly rack struts (5) of the annealing
rack element (1) are deta"chably connected to one
another, particularly by plug-in connections.
6. The annealing rack according to one of Claims 3
through 5,
characterized in that the rest (3), the corner
supports (6), and possibly the rack struts (5) of
the annealing rack element (1) are connected to one
another with play.
7. The annealing rack according to one of the preceding
claims,
characterized in that at least one of the annealing
rack elements (1) is provided with means for
detachable fixing of the annealing basket (13).
8. The annealing rack according to one of the preceding
claims,
characterized in that the annealing basket (13) has
a basket floor (14) having upwardly projecting
basket supports (18).
9. The annealing rack according to Claim 8,
characterized in that in at least one of the
annealing baskets (13), the basket supports (18) are
connected to the basket floor (14) and/or to one
another using basket struts (19).
10. The annealing rack according to Claim 8 or 9,
characterized in that the basket floor (14), the
basket supports (18), and possibly basket struts
- 20 -
(19) of the annealing basket (13), are connected to
one another detachably, particularly by plug-in
connections.
11. The annealing rack according to one of Claims 8
through 10,
characterized in that the basket floor (14), the
basket supports (18), and possibly the basket struts
(19) of the annealing basket (13) are connected to
one another with play.
12. The annealing rack according to one of Claims 8
through 11,
characterized in that wire clips (30) may be
attached detachably, particularly plugged in and/or
screwed in, to the basket floor (14) and/or the
basket supports (18) and/or the basket struts (19).
13. The annealing rack according to one of the preceding
claims,
characterized in that at least one of the annealing
baskets (13) is provided with means for detachable
fixing on the annealing rack element (1).
Disclosed is an annealing frame, especially for conveying molded aluminum parts during a heat treatment process. The invention is characterized in that said annealing frame comprises at least one annealing frame element (1) that is provided with at least one annealing basket (13) which can be placed therein and can be adapted to the annealing material. Annealing material having the most different shapes can be accommodated in a non-tipping and slip-proof manner in said annealing basket (13) while being conveyed during the thermal treatment process.
