Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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METHOD AND MEANS FOR PROCESSING METAL SHEETS
The invention relates to a method and means for
processing metal sheets and the product produced thereby, and
more particularly a method and means for processing metal sheets
which have defects or distortions which also may be latent, and
; 5 the product produced thereby in which such defects and
distortions are removed.
Heretofore, many metal products have been made from
flexible sheets of steel, aluminium and other metals. Metal
sheets and especially sheets made of steel, usually have various
l~ defects or distortions resulting from the manufacturing,
handling and storing of the material, which distortions are
commonly known in the trade as l'oil can," I'camber,'' llcenter
buckle," and "edge wave." Such defects in the metal, in many
cases become more evident when rolls of sheet material or large
sheets of metal are cut into smal~er blanks for processing
and/or after being made into the final product. Unless such
deformities are removed before or during processing, the
resulting product will have evident defects or undesirable
deformities. Although sheet metal may be ordered to
specification as perfectly flat, such metal material is much
more costly and still may contain latent "shapes" which become
evident only after the material is subjected to a forming
process.
Therefore, a principal object of the invention is to
provide a new and improved method and means for processing metal
sheets which may utili~e material blanks which are not perfectly
flat for producing metal sheet products without defects or
distortions.
Another object of the invention is to provide a new
and improved method and means for producing metal products from
sheet metal material which has been painted or otherwise coated
prior to processing.
Another object of the invention is to provide a new
and improved method and means for processing metal sheets which
remove apparent and latent defects in sheet metal without
adversely affecting the metal product as a result of the method
and mean utilized.
Another object of the invention is to provide a new
and improved method and means for processing metal sheets for
producing deeply embossed panels from which apparent, and latent
defects have been removed.
Another object of the invention is to provide a new
and improved method and means for processing metal sheets which
allow the use of inexpensive sheet material Eor producing metal
products of desired quality.
Another object of the invention is to provide a new
; and improved method and means for processing metal sheets which
is efficient, inexpensive and highly productive.
The above objects as well as many other objects o~ the
invention are achieved by providing a method for processing
metal sheets which includes the steps of applying tensile stress
to an intermediate region o~ a sheet oE metal by engaging the
sheet on opposite sides of the regionl de~orming the intermediate
region o~ the sheet, and removing the tensile stress applied to
the sheet. The tensile stress is applied to the intermediate
region of the sheet by ~orming at least one set of beads in the
sheet on opposite sides of the region, and then embossing the
intermediate region. ~fter the intermediate region has been
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embossed and the tensile stress is removed from the sheet, the
beads formed on opposite sides of the intermediate region of the
sheet are removed by trimming. This leaves a sheet metal
product having an embossed region~ and which product does not
include the defects and imperfections which may have been
present prior to the processing of the sheet of metal. This
method is most effective especiall~ in connection with steel
which has a memory or "spring back" tending to maintain defects
which are present in the material.
The means oE the invention includes a first means for
engaging a metal sheet on opposite sides and applying tensile
stress to its intermediate region, second means for deforming
the intermediate region, second means for de~orming the
intermediate region of the sheet while the stress is applied by
the first means, and third means for supporting the first and
second means. The first and second means respectively include
~~~ first and second sets of engageable and disengageable
corresponding male and female die members, the first set of die
members forming a bead in opposite sides of the metal sheet to
apply tensile stress to the intermediate region of the sheet,
and the second set of die members embossing the intermediate
region oE the sheet. The third means supports the first and
second sets of die members for respective movement into engaged
and disengaged positions, and includes fourth means activating
the third means for moving the first set of die members into
engagement while the second set of die members are disengaged,
moving the second set of die members into engagement and
disengagement while the Eirst set of die members are engaged,
and disengaging the first set of die members after the second
set of die members are disengaged.
"
:
The foregoing and other objects of the invention will
become more apparent when the following detailed description of
the invention is read in conjunction with the drawing, in which:
FIGURE 1 is a top plan view of a met.al product of the
invention,
FIGURE 2 is a top plan view of the metal product of
FIGURE 1, prior t.o the trimming operation,
FIGURE 3 is a top plan view of a sheet metal blank used
by the invention for producing the sheet metal product of ~IGURE
1,
FIGURE 4 is a sectional view of a portion of the means
-for carrying out the method and producing the metal product of
the invention,
FIGURE 5 is a top plan view taken on the line 5~5 of
FIGURE 4,
FIGUR~ 6 is an enlarged fra~mentary view of the means
of FIGURE 4 shown within the dashed lines 6,
FIGURE 7 is a view similar to FIGURE 6 illustrating the
formation of a bead in the sheet of metal,
2~ FIGURE 8 is a view similar to FIGURE 5 illustrating the
embossing of the intermediate region of the sheet of metal, and
FIGURE 9 is a sectional view of another form of means
for carrying out the method and producing the metal product of
the invention.
Like numerals designate like parts throughout the
several views.
In referring to the figures, FIGURE 1 illustrates a
sheet metal product produced by the invention in the form of a
rectangular door panel. The door panel 10 is made of a sheek of
malleable material, such as steel or aluminium, that has been
deeply embossed to provide a design formed by the pair of the
depressed rectangular region 12. at the top and the four
triangular depressed regions 14 providing a substantially square
outer rectangular configuration extending ~rom the intermediate
portion to the bottom of the panel 10~ The regions 16 bordering
the embossed designs 12 and 14 and extending between them are
flat and do not have deEects or distortions which may have been
present in the original rectangular blank sheet 18 of metal shown
in FIGURE 3.
In the process o making the panel 10l the blank sheet
18 i5 subjected to means which form pairs of beads 20 and 22 in
the sheet 18 extending along the longitudinal edges 24 and 26 of
the blank sheet 18. A pair of transverse beads 28 are also
formed at the top and bottom of the blank sheet 18 p~oximate to
its edges 30 and 32. The forming of the beads 20, 22 and 28
about the intermediate region 34 of the sheet 18, takes up
material and results in the application o~ tensile stress to the
intermedia~e region 34. After forming the beads 20, 22 and 28,
the beads are maintained in their fixed position, so that the
tensile stress produced in the intermediate region is not
relieved until the completion of the sheet fabricating operation.
The talce-up of material by the forming of the beads 20, 22 and 28
is evident along the outer edges 24, 26, 30 and 32 by the concave
edge regions 36 produced opposite to the beads 20, 22 and 28.
With the beads formed and maintained in spaced position
on opposite sides of the intermediate region 34, the designs
provided by the embossed regions 12 and 14 are formed. This may
be done by the use of male and female die members, as well known
in the art. The beads, 20, 22, 28 may also have been ~ormed by
die members which are maintained in position and engagement with
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the blanl~ 18 during the deformatlon of the inte~mediate region 3
during the embossing operation. With the completion of the
embossing operation, in the intermediate region 34, the tension
applied to the blank 18 is removed from the intermediate region
34 and the blank 18 is released~
At this time~ the blank 18 appears as shown in FIGVRE
2. The intermediate region 34 and the beads 20, 22 and 28 retain
their configuration and integrity and the portion 16 of the
intermediate region 34 which has not been embossed remains flat
and void o~ defects ~hich may have ori~inally been present in the
blank 18.
In order to provide t:he final product 10, the blank 18
is trimmed along the dashed line 38 to remove the beads 20, 22
and 28 and provide the rectangular outer edges 90 of the door
panel 10 shown in FIGURE 1~ With the trimming of the beads 20,
22 and 28, the door panel 10 does not suffer deformation or
evidence defects which may have been present or latent in the
original sheet 18 shown in ~IGURE 3.
Although FIGURES 1 and 2 illustrate a particular
design, the invention may be applied to produce various designs
and configllrations while allowing the use of stock material which
contain apparent and latent deects to provide high qua].ity
products from which such defects are absent. Although the
illustrated sets of beads 20, 22 and 28 are disconnected and
positioned directly opposite to the embossed regions 12 and 1~ of
the sheet 18l the beads may be continuous and without
interruption, or may otherwise be arranged to provide the
advantages of the invention.
It is also note that in addition to not requiring
special flat metal stock, the blank sheet 18 utilized may also be
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prepainted. This allows the production of the final metal
product without requiring an additional painting or finishing
step. This results in costs saving, since the original sheet
metal may be processed in large sheets or strips suitable for
mass production techniques.
Refer to FIGURES 4 to 8 for a descript:ion of the means
or apparatus 40 for processing metal sheets in accordance with
the invention. The apparatus 40 comprises a base plate 42 and
top plates 44 and 46 which are moveable with respect to the base
plate 42. The base plate 42 provides a top surface 4~ having
elongated slots 50 (FIGURE 4) along its edges 52. The slots 50
receive elongated inserts 54, 56 and 58 arranged in opposite
pairs. The inserts 54, 56 and 58, are each secured within their
respective slots 50 by bolt means 59 (FIGURE 6). The inserts 54,
56, and 58 each provide a male die member for forming a bead in
blank sheet 18, which is to be processed by the apparatus 40. A
plurality of bodies 60 depend from the top plate 44 each
supported by a normally extended retractable unit 62. The bodies
60 are normally positioned over the edge portions 52 of the base
plate 42 and in spaced relationship therefrom as shown in FIGURES
4 and 6. Each oE the bodies 60 are also provided with an
elongated slot 64 in its bott:om surface 65 (FIGURE 61 for
receivlng inseLts 66. Each insert 66 provides a female die
member which is removeable secured in its slot 64 by bolt means
68. The male and female die members of the inserts 56 and 66 are
arranged so that the protrusion 72 of each insert 56 enters a
select one of the grooves 70 oE the proximately positioned lnsert
66 for forming a bead such as the bead 22 in the blank shet 18 as
illustrated in FIGURE 7.
In order to adjust the location of and distance of the
beads of each pair of beads with respect to each other and the
edges of the sheet 18, the male inserts 56 may be removed and
replaced by inserts providing a protrusion 72 at a locatlon
corresponding to another groove 70 of the female die members 66.
S The ability to change the distance between pa.irs of beads formed
in the sheet material 18 is of impor~ance, since if a smaller
metal product is to be produced, spacing the pairs of beads more
closely together~ allows the use of a smaller blank sheet o
material. This reduces the amount of metal used and the cost of
the Einal product.
The central region 74 of the base plate 42 is cut out
to receive a rectangular female die member 76 intermediate to the
die members 56 which are positioned about its edges 52. The
marginal regions 78 o~ the die member 76, as well as other
regions 80, are flat and level with the top surfaces 48 of the
edges 52 of the base plate 42. A complementary male die member
82 is secured by bolt means 84, to the bottom surface of the top
plate 46 and normally spaced above the die member 76 as
illustrated in FIG~RE 4. The top plate 46 and die member 82 are
supported by spring means 87 in their normal positions shown in
FIGURE 4, and are moveable in a downward direction when
activated, so that the die members 76 and 82 deform the
intermediate region of the sheet 18 by deep embossing as shown in
FIGURE 8. The top plate 46 is also provided with openings 86
through which the retractable units 62 extend for supporting the
bodies 60. The top means 44 and 46 are maintained in their
normal position by means shown in FIGURE 4 and by means which
will be explained more ~ully in connection with the operation o-~
the apparatus 40.
In operation of the apparatus 40, a blank sheet o
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metal 18 is positioned as shown in FIGURE 6 over the base member
42 between the sets oE die members. The apparatus 40 may be
activated by the application of compressive force by members 41
and 43 of a conventional means such as a hydraulic press to the
top and bottom plates 44 and 42. This results in the downward
movement of the top plate ~4 and oE the bodies 60 supported
thereby. The continued downward movement of the bodies 60
results in the engagement and application of force to the end
portions of the blank sheet 18 by the inserts 56 and 66 as shown
in FIGURE 7, and the gripping and the forming of beads such as
the beads 20, 22 and 28 in the blank 18 of FIGURE 2. The forming
of the beads takes up material from the intermediate region 34 of
the blank 18 applying a tensile s~ress thereto. The formation of
the beads also results in depletion of material from along the
edges of regions 36 of sheet 18 proximate to the beads as also
shown in FIGURE 2.
With the die members of inserts 56 and 66 in engagement
with the sheet 18 and still applying tensile stress to its
intermediate regionr the continued downward motion of the top
plate 44 results in the retraction of the units 62 and the
engagement of the step 88 of plate 4~ with the top surface of the
top plate 46 in the region of its opening 86. The continued
downward motion of the top plate 44 results in the downward
movement of the plate 46, the compression of coil springs 87
positioned between it and the member 43, and its engagement with
the intermediate region 34 of the blank sheet 18 as shown in
FIGURE 8. The full movement of the top plate 44 to its bottom
position results in the application of high force by the
complementary die members 76 and 82 to the sheet 18 providing the
deeply embossed designs shown in FIGUXES 1 and 2 in the regions
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12 and 14.
At this time, the applied force is removed with the
upward movement of the top plate 44 towards its normal position,
allowing the plate 46 to move in turn upwardly into its normal
S position out of engagement with the intermediate region 34 of the
blank sheet 18. The continued upward movement of the top plate
44 allows complete extension of the retractable unit 62 and then
the release of the edge portions of the blank 18 by the bead
forming die members. The blank sheet 18 which has now been
processed to the form shown in FIGURE 2 is stripped and removed
from the apparatus 40. The formed blank 18 is finished upon the
removing of the edge portions including the beads 20, 22 and 28.
This is done by trimming along the dashed line 38 in FIGU~E 2 to
produGe the door panel 10 with edge 9~ of FIGURE 1.
FIGURE 9 is a sectional view of another apparatus 92
; for carrying out the method of the invention, which is a modified
form of the apparatus 40. The apparatus 92 has a base plate 94,
and a top plate 96 which is movable in the upward and downward
directions with respect thereto. An embossing -female die member
g8 is centrally secured on the top surface of the base plate 94,
while the male embossing die member 100 is centrally secure to
the bottom sur~ace of the top plate 96 in spaced relationship
above the bottom die member 98~ The base and top plates 94 and
96 are provided with a plurality of spaced threaded openings 106,
108 through their top and bottom surfaces along their edge
portions 100~ 102. A pair oE bodies are detachably secured to
the base plate 94 by bolt means 114, allowing the bodies 110, 112
to be positioned at various locations with respect to each other
and their inter~ediate die member 98. Each of the bodies 110,
112 has an insert 116 providing a male die member for forming a
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bead 22 along an edge portion of the blank sheet 18 as illustrated
in E~IGURE 9. A pair of bodies 118, 120 are similarly secured b~
bolt means 122 to depend from the bottom surface of the top plate
96. A pair of female die members 124, 126 are respectively
secured in depending relationship with the bodies 118, 120 by a
plurality of spring elements 128. The die members 124, 126 are
normally positioned above and in spaced relationship to the male
die members provided by the inserts 116 of the bodies 110, 112.
In operation, the top plate 96 is normally in a
position raised with respect to that shown in FIGURE 9, and a
space is provided between the die members allowing the
positioning of a blank sheet 18 over the surfaces of the bodies
110 and 112, the inserts 116, and of the embossing die ~ember 98.
With the activation of the apparatus 92, a compressive force is
applied by the members 41 and 43 to the top and bottom plates 96,
94 resulting in the downward movement of the top plate 96 and in
the engagement of the die members 124 and 126 with the marginal
: regions of the blank sheet 18. With the continued downward
movement of the top plate 96, increasing force is exerted on the
sheet 18 through the spring elements 128. This results in
securely clamping and positioning the edge portions of the blank
sheet 18 between the die members 124, 126 and the corresponding
male insert members 116 of the bodies 110 and 112. This action
forms the beads 22 and applies a tensile stress to the
intermediate region 34 of the sheet 18. FIGURE 9 shows the stage
where the beads 22 have just been Eormed and tensile stress is
exerted on the intermediate region 34 oE the sheet 18. Continued
downward movement of the top plate 96 increases the clamping
action with which the edges are secured between the inserts 116
and their corresponding die members 124, 126 and causes the top
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central die member 100 to deform the intermediate region 34 of
the sheet 18. The intermediate region of sheet 18, is thus,
deformed for example to provide the deep embossed designs as
illustrated in FIGURE 2. With the completion of the embossing
operation, the force exerted on the top member 96 is reduced and
the top plate is moved in the upward direction disengaging the
die member 100 from the intermediate regioll 34 of the sheet 18.
The further upward movement of the top plate 96 allows the spring
element 124 to extend to their normal conaition followed by the
upward movement of the die members 124, 126. This results in
disengagement of the die members 124, 126 from the top surface
and the beads 22 formed in the sheet 18. In its normal
deactivated condition, the apparatus 92 provides a space between
its die members allowing the stripping and removal of the formed
sheet 18. As explained previously in connection with the
apparatus 40, the formed sheet 18 has an appearance such as shown
in FIGURE 2, and is ~inished by trimming along the line 38 to
produce the finished sheet metal product.
Although, for purposes of illustration, the invention
was described in connection with the production of a door panel,
it is understood that many other articles and designs may be
manufactured by the method and means of the invention with
appropriate modifications but without departing from the spirit
of the invention.
