U.S. patent application number 15/382850 was filed with the patent office on 2018-06-21 for truncated dome cup.
This patent application is currently assigned to Stolle Machinery Company, LLC. The applicant listed for this patent is Stolle Machinery Company, LLC. Invention is credited to Gregory H. Butcher, Aaron E. Carstens, Patrick K. McCarty, James A. McClung, Paul L. Ripple.
Application Number | 20180170606 15/382850 |
Document ID | / |
Family ID | 62556717 |
Filed Date | 2018-06-21 |
United States Patent
Application |
20180170606 |
Kind Code |
A1 |
Carstens; Aaron E. ; et
al. |
June 21, 2018 |
TRUNCATED DOME CUP
Abstract
A formed blank is provided. The formed blank includes a
stretched portion and/or a truncated protrusion, a tooling assembly
structured to form a formed blank including a stretched portion
and/or a truncated protrusion, and a method of forming a formed
blank including a stretched portion and/or a truncated protrusion.
The formed blank includes a base and a depending sidewall. The
stretched portion and/or the truncated protrusion is disposed on
the formed blank base and the thickness of the stretched portion
and/or the truncated protrusion is less than the sidewall. The
stretched portion and/or the truncated protrusion utilizes less
material relative to an unformed base that has about the same
thickness as the sidewall.
Inventors: |
Carstens; Aaron E.;
(Centerville, OH) ; McCarty; Patrick K.; (Dayton,
OH) ; McClung; James A.; (Canton, OH) ;
Ripple; Paul L.; (Canton, OH) ; Butcher; Gregory
H.; (Naples, FL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Stolle Machinery Company, LLC |
Centennial |
CO |
US |
|
|
Assignee: |
Stolle Machinery Company,
LLC
Centennial
CO
|
Family ID: |
62556717 |
Appl. No.: |
15/382850 |
Filed: |
December 19, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B21D 22/28 20130101;
B65D 1/40 20130101; B21D 25/00 20130101; B21D 22/30 20130101; B21D
51/26 20130101; B65D 1/165 20130101 |
International
Class: |
B65D 1/16 20060101
B65D001/16; B21D 22/28 20060101 B21D022/28; B21D 51/26 20060101
B21D051/26; B65D 1/40 20060101 B65D001/40 |
Claims
1. A formed blank comprising: a body including a base; and the base
including a truncated protrusion.
2. The formed blank of claim 1 wherein the truncated protrusion is
a truncated dome.
3. The formed blank of claim 2 wherein: the truncated dome includes
a first generally curvilinear portion and a second generally
curvilinear portion; the truncated dome first generally curvilinear
portion having a first center; and the truncated dome second
generally curvilinear portion having a second center.
4. The formed blank of claim 3 wherein: the truncated dome first
generally curvilinear portion is a first generally arcuate portion;
and the truncated dome second generally curvilinear portion is a
second generally arcuate portion.
5. The formed blank of claim I wherein the stretched portion of the
truncated protrusion has a generally uniform thickness.
6. The formed blank of claim 1 wherein the formed blank has a base
gauge and wherein; the body includes a sidewall depending from the
base: the sidewall has a thickness generally corresponding to the
base gauge; and the truncated protrusion has a thickness that is
less than the sidewall.
7. The formed blank of claim 6 wherein the truncated protrusion has
a thickness that is between about 0.0003 inch and 0.002 inch
thinner than the sidewall.
8. The formed blank of claim 1 wherein the formed blank has a
reduced volume.
9. Tooling assembly for forming a blank of material into a formed
blank, the formed blank including a base and a depending sidewall,
the tooling assembly comprising: a first tool assembly; a second
tool assembly; the first tool assembly and the second tool assembly
structured clamp the blank of material at the periphery of the
base; the first tool assembly and the second tool assembly
structured to stretch a portion of the base and thereby thin the
base stretched portion relative to the sidewall; and wherein the
base stretched portion is generally uniform in thickness.
10. The tooling assembly of claim 9 wherein: the first tool
assembly includes a forming punch; the second tool assembly
includes a forming surface; wherein the forming surface includes a
truncated protrusion forming profile; and wherein the forming punch
moves the blank of material into contact with the truncated
protrusion forming profile.
11. The tooling assembly of claim 10 wherein the forming surface
includes a truncated dome forming profile.
12. The tooling assembly of claim 11 wherein: the truncated dome
forming profile includes a first generally curvilinear portion and
a second generally curvilinear portion; the truncated dome forming
profile first generally curvilinear portion having a first center;
and the truncated dome forming profile second generally curvilinear
portion having a second center.
13. The tooling assembly of claim 12 wherein: the truncated dome
forming profile first generally curvilinear portion is a first
generally arcuate portion; and the truncated dome forming profile
second generally curvilinear portion is a second generally arcuate
portion.
14. The tooling assembly of claim 9 wherein the blank of material
has a base gauge prior to being formed and wherein: the first tool
assembly and the second tool assembly are structured to form the
blank of material into a formed blank including a base and a
sidewall; the first tool assembly and the second tool assembly are
structured to form the formed blank base with a truncated
protrusion; and the first tool assembly and the second tool
assembly are structured to form the formed blank sidewall with a
thickness about the same as the base gauge; and the first tool
assembly and the second tool assembly are structured to form the
formed blank truncated protrusion with a thickness that is less
than the formed blank sidewall.
15. The tooling assembly of claim 14 wherein the first tool
assembly and the second tool assembly are structured to form the
formed blank truncated protrusion with a thickness that is between
about 0.0003 inch and 0.002 inch thinner than the formed blank
sidewall.
16. A method of forming a formed blank within a tooling assembly,
the tooling assembly including a first tool assembly and a second
tool assembly, the method comprising: forming a blank of material
to include a base and a depending sidewall; clamping the blank
between the first tool assembly and the second tool assembly at the
periphery of the base; and stretching the base thereby thinning a
portion of the base relative to the sidewall to form a stretched
portion.
17. The method of claim 16 stretching the base thereby thinning a
portion of the base relative to the sidewall to form a stretched
portion includes stretching the base stretched portion so as to
have a generally uniform thickness.
18. The method of claim 16 wherein stretching and thereby thinning
a portion of the base relative to the sidewall to form a stretched
portion includes forming a truncated protrusion.
19. The method of claim 18 wherein forming a truncated protrusion
includes forming a truncated dome.
20. The method of claim 18 wherein forming a truncated dome
includes: forming a dome with a first generally curvilinear portion
and a second generally curvilinear portion; forming the first
generally curvilinear portion about a first center; and forming the
second generally curvilinear portion about a second center.
21. The method of claim 16 wherein the blank has a base gauge and
wherein forming the blank of material to include a base and a
depending sidewall and stretching and thereby thinning a portion of
the base relative to the sidewall to form a stretched portion
include: forming the sidewall with a thickness generally
corresponding to the base gauge; and forming the stretched portion
with a thickness that is less than the formed blank sidewall.
22. The method of claim 21 wherein forming the stretched portion
with a thickness that is less than the formed blank sidewall
includes forming the stretched portion with a thickness that is
between about 0.0003 inch and 0.002 inch thinner than the
Description
BACKGROUND OF THE INVENTION
Field of the Invention
[0001] The disclosed concept relates generally to containers and,
more particularly, to metal containers such as, for example, beer
or beverage cans, as well as food cans. The disclosed concept also
relates to cups and blanks for forming cups and containers. The
disclosed concept further relates to methods and tooling for
selectively forming a cup or bottom portion of a container to
reduce the amount of material in the cup or bottom portion.
Background Information
[0002] It is generally well known to draw and iron a sheet metal
blank to make a thin walled container or can body for packaging
beverages (e.g., carbonated beverages; non-carbonated beverages),
food or other substances. As is known, many such containers have a
generally cylindrical shape and the example discussed herein is
assumed to have such a shape. It is understood, however, that the
disclosed container (as well as the cup that becomes the container)
method for forming such a container/cup is not limited to this
specific shape.
[0003] One of the initial steps in forming such containers is to
form a cup. As shown in FIG. 1, the cup begins as a generally
planar blank I cut from sheet material. The blank 1 is then drawn
into a cup 2. The cup 2 is generally shorter and wider than the
finished container. Accordingly, the cups 2 are typically subjected
to a variety of additional processes that further form the cup into
the finished container. The cup includes a base 3 having an
upwardly depending sidewall 4. The container body, hereinafter can
body 5 (FIG. 2), is formed by additional processes such as, but not
limited to, drawing, redrawing, and ironing the cup 1. The can body
5 also includes a base 6 and a sidewall 7. The can body base 6
includes a bottom profile. That is, as used herein, a "bottom
profile" is the shape of the base 3, 6 after forming. Generally, a
beverage can body 5A, the bottom profile slopes inwardly from an
annular ridge 8 to form an inwardly projecting, generally
hemispherical dome 9. Conversely, a food can body 5B (shown during
formation in FIG. 4E) has a generally flat bottom profile. The dome
9 is formed by a "domer" during the forming of the cup 2 and/or a
can body 5. The apparatus and tooling structured to form a cup 2
and/or a can body 5 is shown in U.S. patent application Ser. No.
15/286,954, which is incorporated by reference.
[0004] There is a constant desire in the industry to reduce the
gauge, and thus the amount of material used to form such
containers. However, among other disadvantages associated with the
formation of containers from relatively thin gauge material, is the
tendency of the container to wrinkle, particularly during redrawing
and doming. Prior proposals have, in large part, focused on forming
bottom profiles of various shapes that were intended to be strong
and, therefore, capable of resisting buckling while enabling metal
having a thinner base gauge to be used to make the can body. As
used herein, "base gauge" means the initial thickness of the
material and is not limited to the thickness of the base
portion/element. Thus, the conventional desire has been to maintain
the material thickness in the dome and bottom profile to maintain
or increase strength in this area of the can body and thereby avoid
wrinkling.
[0005] Tooling for forming domed cups or can bodies has
conventionally included a curved, or arcuate, punch core and a die
core with a corresponding curvature, such that a domed can body is
formed from material (e.g., without limitation, a sheet metal
blank) conveyed between the punch core and the die core. Typically,
the punch core extends downwardly into the die core, forming the
domed cup or can body. During this forming operation, the material
is drawn between the punch core and the die core. That is, in order
to maintain the thickness of the domed portion, the material is
relatively lightly clamped on either side of the portion to be
domed. Thus, the material can move (e.g., slide) or flow toward the
dome as it is formed in order to maintain the desired thickness in
the bottom profile. Further, as shown in U.S. Pat. No. 5,394,727,
it is known to form a bottom profile including generally planar
(when viewed in cross-section) surfaces instead of a dome. Such
protrusions are also formed by drawing the material over a die. The
domes and protrusions of the known art are structured to generally
maintain the thickness of the material during the formation of a
dome.
[0006] Further, can bodies formed from a cup with a generally
hemispherical dome also have disadvantages. For example, certain
beverage can bodies are formed by reversing, or flattening, the
dome on the cup and reforming the dome on the can body. The steps
to this process are shown in FIGS. 3A-3C and include reversing the
dome (FIGS. 3B and 3C) and reforming a can body dome (FIGS. 3D and
3E). It is noted that a cup's generally arcuate dome, i.e., a
generally hemispherical dome is generally arcuate in cross-section
as shown in the figures, defines a volume of metal. This volume of
metal must be reformed when the cup is formed into a can body.
Further, it is noted that a generally arcuate dome includes a
greater volume of metal relative to other shapes such as, but not
limited to a truncated dome, as shown in FIG. 5A, discussed below.
This greater volume of metal allows the metal to wrinkle or have
other defects during the formation of the can body. This is also
true for food can bodies, which typically have a generally planar
bottom, when formed from a cup with a generally arcuate dome. That
is, the steps of forming a food can body are shown in FIGS. 4A-4E.
As with beverage can bodies, the greater volume of metal in a
generally hemispherical dome, i.e., a generally arcuate dome when
viewed in cross-section, allows for the formation of defects in the
food can body when the cup is reformed.
[0007] There is, therefore, room for improvement in containers such
as beer/beverage cans and food cans, as well as in selectively
formed cups and tooling and methods for providing such cups and
containers. That is, the problem in the known art is that the cup,
or can body, uses too much material, especially in the base.
SUMMARY OF THE INVENTION
[0008] The disclosed and claimed concept provides for a formed
blank including a stretched portion and/or a truncated protrusion,
a tooling assembly structured to form a formed blank including a
stretched portion and/or a truncated protrusion, and a method of
forming a formed blank including a stretched portion and/or a
truncated protrusion. The formed blank includes a base and a
depending sidewall. The stretched portion and/or the truncated
protrusion is disposed on the formed blank base and the thickness
of the stretched portion and/or the truncated protrusion is less
than the sidewall. The stretched portion and/or the truncated
protrusion utilizes less material relative to an unformed base that
has about the same thickness as the sidewall. As such, the formed
blank, the tooling for forming the formed blank, and the method of
forming the formed blank solve the problems stated above.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] A full understanding of the invention can be gained from the
following description of the preferred embodiments when read in
conjunction with the accompanying drawings in which:
[0010] FIG. 1 is a cross-sectional view of a prior art cup.
[0011] FIG. 2 is a cross-sectional view of a prior art can
body.
[0012] FIGS. 3A-3E show the formation of a prior art beverage can
body.
[0013] FIGS. 4A-4E show the formation of a prior art food can
body.
[0014] FIG. 5A is a cross-sectional view of a formed blank in the
form of a cup. FIG. 5B is a cross-sectional view of a formed blank
in the form of a can body.
[0015] FIG. 6 is a partially schematic, cross-sectional view of a
tooling assembly.
[0016] FIG. 7 is a detail cross-sectional view of a domer
structured to form a truncated protrusion.
[0017] FIGS. 8A-8E show the formation of a beverage can body from a
cup with a truncated dome.
[0018] FIGS. 9A-9E show the formation of a food can body from a cup
with a truncated dome.
[0019] FIG. 10 is a flow chart for the disclosed method.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0020] Directional phrases used herein, such as, for example,
clockwise, counterclockwise, left, right, top, bottom, upwards,
downwards and derivatives thereof, relate to the orientation of the
elements shown in the drawings and are not limiting upon the claims
unless expressly recited therein.
[0021] As used herein, the singular form of "a," "an," and "the"
include plural references unless the context clearly dictates
otherwise.
[0022] As used herein, "structured to [verb]" means that the
identified element or assembly has a structure that is shaped,
sized, disposed, coupled and/or configured to perform the
identified verb. For example, a member that is "structured to move"
is movably coupled to another element and includes elements that
cause the member to move or the member is otherwise configured to
move in response to other elements or assemblies. As such, as used
herein, "structured to [verb]" recites structure and not function.
Further, as used herein, "structured to [verb]" means that the
identified element or assembly is intended to, and is designed to,
perform the identified verb. Thus, an element that is merely
capable of performing the identified verb but which is not intended
to, and is not designed to, perform the identified verb is not
"structured to [verb]."
[0023] As used herein, "associated" means that the elements are
part of the same assembly and/or operate together, or, act
upon/with each other in some manner. For example, an automobile has
four tires and four hub caps. While all the elements are coupled as
part of the automobile, it is understood that each hubcap is
"associated" with a specific tire.
[0024] As used herein, the statement that two or more parts or
components are "coupled" shall mean that the parts are joined or
operate together either directly or indirectly, i.e., through one
or more intermediate parts or components, so long as a link occurs.
As used herein, "directly coupled" means that two elements are
directly in contact with each other. As used herein, "fixedly
coupled" or "fixed" means that two components are coupled so as to
move as one while maintaining a constant orientation relative to
each other. Accordingly, when two elements are coupled, all
portions of those elements are coupled. A description, however, of
a specific portion of a first element being coupled to a second
element, e.g., an axle first end being coupled to a first wheel,
means that the specific portion of the first element is disposed
closer to the second element than the other portions thereof.
Further, an object resting on another object held in place only by
gravity is not "coupled" to the lower object unless the upper
object is otherwise maintained substantially in place. That is, for
example, a book on a table is not coupled thereto, but a book glued
to a table is coupled thereto.
[0025] As used herein, a "fastener" is a separate component
structured to couple two or more elements. Thus, for example, a
bolt is a "fastener" but a tongue-and-groove coupling is not a
"fastener." That is, the tongue-and-groove elements are part of the
elements being coupled and are not a separate component.
[0026] As used herein, the phrase "removably coupled" or
"temporarily coupled" means that one component is coupled with
another component in an essentially temporary manner. That is, the
two components are coupled in such a way that the joining or
separation of the components is easy and would not damage the
components. For example, two components secured to each other with
a limited number of readily accessible fasteners, i.e., fasteners
that are not difficult to access, are "removably coupled" whereas
two components that are welded together or joined by difficult to
access fasteners are not "removably coupled." A "difficult to
access fastener" is one that requires the removal of one or more
other components prior to accessing the fastener wherein the "other
component" is not an access device such as, but not limited to, a
door.
[0027] As used herein, "temporarily disposed" means that a first
element(s) or assembly (ies) is resting on a second element(s) or
assembly(ies) in a manner that allows the first element/assembly to
be moved without having to decouple or otherwise manipulate the
first element. For example, a book simply resting on a table, i.e.,
the book is not glued or fastened to the table, is "temporarily
disposed" on the table.
[0028] As used herein, "operatively coupled" means that a number of
elements or assemblies, each of which is movable between a first
position and a second position, or a first configuration and a
second configuration, are coupled so that as the first element
moves from one position/configuration to the other, the second
element moves between positions/configurations as well. It is noted
that a first element may be "operatively coupled" to another
without the opposite being true.
[0029] As used herein, a "coupling assembly" includes two or more
couplings or coupling components. The components of a coupling or
coupling assembly are generally not part of the same element or
other component. As such, the components of a "coupling assembly"
may not be described at the same time in the following
description.
[0030] As used herein, a "coupling" or "coupling component(s)" is
one or more component(s) of a coupling assembly. That is, a
coupling assembly includes at least two components that are
structured to be coupled together. It is understood that the
components of a coupling assembly are compatible with each other.
For example, in a coupling assembly, if one coupling component is a
snap socket, the other coupling component is a snap plug, or, if
one coupling component is a bolt, then the other coupling component
is a nut.
[0031] As used herein, "correspond" indicates that two structural
components are sized and shaped to be similar to each other and may
be coupled with a minimum amount of friction. Thus, an opening
which "corresponds" to a member is sized slightly larger than the
member so that the member may pass through the opening with a
minimum amount of friction. This definition is modified if the two
components are to fit "snugly" together. In that situation, the
difference between the size of the components is even smaller
whereby the amount of friction increases. If the element defining
the opening and/or the component inserted into the opening are made
from a deformable or compressible material, the opening may even be
slightly smaller than the component being inserted into the
opening. With regard to surfaces, shapes, and lines, two, or more,
"corresponding" surfaces, shapes, or lines have generally the same
size, shape, and contours.
[0032] As used herein, a "planar body" or "planar member" is a
generally thin element including opposed, wide, generally parallel
surfaces, i.e., the planar surfaces of the planar member, as well
as a thinner edge surface extending between the wide parallel
surfaces. That is, as used herein, it is inherent that a "planar"
element has two opposed planar surfaces. The perimeter, and
therefore the edge surface, may include generally straight
portions, e.g., as on a rectangular planar member, or be curved, as
on a disk, or have any other shape.
[0033] As used herein, a "path of travel" or "path," when used in
association with an element that moves, includes the space an
element moves through when in motion. As such, any element that
moves inherently has a "path of travel" or "path."
[0034] As used herein, the statement that two or more parts or
components "engage" one another shall mean that the elements exert
a force or bias against one another either directly or through one
or more intermediate elements or components. Further, as used
herein with regard to moving parts, a moving part may "engage"
another element during the motion from one position to another
and/or may "engage" another element once in the described position.
Thus, it is understood that the statements, "when element A moves
to element A first position, element A engages element B," and
"when element A is in element A first position, element A engages
element B" are equivalent statements and mean that element A either
engages element B while moving to element A first position and/or
element A either engages element B while in element A first
position.
[0035] As used herein, "operatively engage" means "engage and
move." That is, "operatively engage" when used in relation to a
first component that is structured to move a movable or rotatable
second component means that the first component applies a force
sufficient to cause the second component to move. For example, a
screwdriver may be placed into contact with a screw. When no force
is applied to the screwdriver, the screwdriver is merely "coupled"
to the screw. If an axial force is applied to the screwdriver, the
screwdriver is pressed against the screw and "engages" the screw.
However, when a rotational force is applied to the screwdriver, the
screwdriver "operatively engages" the screw and causes the screw to
rotate. Further, with electronic components, "operatively engage"
means that one component controls another component by a control
signal or current.
[0036] As used herein, the word "unitary" means a component that is
created as a single piece or unit. That is, a component that
includes pieces that are created separately and then coupled
together as a unit is not a "unitary" component or body.
[0037] As used herein, the term "number" shall mean one or an
integer greater than one (i.e., a plurality).
[0038] As used herein, in the phrase "[x] moves between its first
position and second position," or, "[y] is structured to move [x]
between its first position and second position," "[x]" is the name
of an element or assembly. Further, when [x] is an element or
assembly that moves between a number of positions, the pronoun
"its" means "[x]," i.e., the named element or assembly that
precedes the pronoun "its."
[0039] As used herein, "about" in a phrase such as "disposed about
[an element, point or axis]" or "extend about [an element, point or
axis]" or "[X] degrees about an [an element, point or axis]," means
encircle, extend around, or measured around. When used in reference
to a measurement or in a similar manner, "about" means
"approximately," i.e., in an approximate range relevant to the
measurement as would be understood by one of ordinary skill in the
art.
[0040] As used herein, a "radial side/surface" for a circular or
cylindrical body is a side/surface that extends about, or
encircles, the center thereof or a height line passing through the
center thereof As used herein, an "axial side/surface" for a
circular or cylindrical body is a side that extends in a plane
extending generally perpendicular to a height line passing through
the center. That is, generally, for a cylindrical soup can, the
"radial side/surface" is the generally circular sidewall and the
"axial side(s)/surface(s)" are the top and bottom of the soup
can.
[0041] As employed herein, the terms "can" and "container" are used
substantially interchangeably to refer to any known or suitable
container, which is structured to contain a substance (e.g.,
without limitation, liquid; food; any other suitable substance),
and expressly includes, but is not limited to, beverage cans, such
as beer and soda cans, as well as food cans.
[0042] As used herein, a "contour" means the line or surface, that
defines an object. That is, for example, when viewed in
cross-section, the surface of a three-dimensional object is reduced
to two dimensions; thus, a portion of a three-dimensional surface
contour is represented by a two-dimensional line contour.
[0043] As used herein, a "perimeter portion" means the area at the
outer edge of a defined area, surface, or contour.
[0044] As used herein, a "truncated protrusion" is a profile for a
cup base or a can body base that includes a "stretched portion" and
a generally planar portion at the distal end of the protrusion,
i.e., the end of the protrusion located furthest from the base.
Thus, as used herein, a "truncated protrusion" inherently includes
a stretched portion and a generally planar portion. Further, as
used herein, a "generally planar portion" of a "truncated
protrusion" includes both substantially planar elements and
elements that include beads, corrugations, or similar constructs
structured to accommodate additional material in a defined area and
relative to a substantially planar element having the same defined
area so long as the area including beads, corrugations, or similar
constructs has generally planar contour over the defined area.
Further, as used herein, a "truncated protrusion" is formed and
offset inwardly. That is, a "truncated protrusion" is formed by
deforming material into the space partially enclosed by a base and
sidewall, such as on a cup of can body. Thus, the formation of an
outwardly protruding bead extending about base does not convert the
generally planar portion of the base encircled by the bead into a
"truncated protrusion" because the generally planar portion of the
base encircled by the bead is not formed or offset inwardly.
[0045] As used herein, a "truncated protrusion forming profile" is
a surface on a forming element, such as, but not limited to, the
surface of a die, structured to form a material into a "truncated
protrusion" as defined above. As used herein, a "die truncated
protrusion forming profile" is a surface on a die, structured to
form a material into a "truncated protrusion" as defined above.
[0046] As used herein, a "truncated dome" is a "truncated
protrusion" having a generally curvilinear (or arcuate) portion and
a generally planar portion when viewed in a lateral cross-section;
that is, a truncated dome is a dome wherein a generally planar
portion is disposed where the vertex of the dome would be, i.e., a
dome with a generally flat top. Further, the "stretched portion"
and the "generally planar portion" are one configuration selected
from the group consisting of coextensive (i.e., fully overlapping),
partially coextensive (i.e., partially overlapping), or separate
(i.e., no overlap).
[0047] As used herein, a "truncated dome forming profile" is a
surface on a forming element, such as, but not limited to, the
surface of a die, structured to form a material into a "truncated
dome" as defined above. As used herein, a "die truncated dome
forming profile" is a surface on a die, structured to form a
material into a "truncated dome" as defined above.
[0048] As used herein a "stretched portion" is a portion of a
material formed by stretching the material. Further, as used
herein, a "stretched portion" is not an unstretched portion that is
capable of being stretched but rather one that has been stretched.
Thus, an unstretched portion that is capable of being stretched is
specifically excluded from the definition of a "stretched portion."
A "truncated protrusion" or a "truncated dome," in an exemplary
embodiment, includes an unstretched portion as well as the required
"stretched portion." That is, a protrusion/dome with only an
unstretched portion, i.e., lacking a "stretched portion," is
specifically excluded from the definition of a "truncated
protrusion" or a "truncated dome." Further, due to the absence of a
"stretched portion," a protrusion formed exclusively by drawing,
such as the protrusion(s) disclosed in U.S. Pat. No. 5,394,727, are
specifically excluded from the definition of a "truncated
protrusion" and a "truncated dome."
[0049] As used herein, a "formed blank" means a cup as well as a
can body that has been formed from a cup.
[0050] As used herein, "depending" means to extend at an angle
other than zero (0.degree.) from another element without regard to
direction. That is, for example, a "depending" sidewall may extend
generally upwardly from a base.
[0051] As used herein, "generally curvilinear" includes elements
having multiple curved portions, combinations of curved portions
and planar portions, and a plurality of planar portions or segments
disposed at angles relative to each other thereby forming a
curve.
[0052] As used herein, "generally" means "in a general manner"
relevant to the term being modified as would be understood by one
of ordinary skill in the art.
[0053] As used herein, "substantially" means "for the most part"
relevant to the term being modified as would be understood by one
of ordinary skill in the art.
[0054] As used herein, "at" means on and near relevant to the term
being modified as would be understood by one of ordinary skill in
the art.
[0055] Generally, and as shown in FIGS. 5A and 5B, a formed blank
10, i.e., a cup 2 or a can body 5, is formed from a blank 1. That
is, blank 1 is formed by a tooling assembly 100, shown partially
schematically in FIG. 6. As is known, the tooling assembly 100
includes a first tool assembly 102 and a second tool assembly 104.
At least one of the first tool assembly 102 and the second tool
assembly 104 is movable and is coupled to a press 106 or similar
device. In an exemplary embodiment, the first tool assembly 102
includes a forming punch 108 and the second tool assembly 104
includes a forming die 110. The press 106 is structured to, and
does, move the first tool assembly 102 between a first position,
wherein the first tool assembly 102 is spaced from the second tool
assembly 104, and a second position, wherein the first tool
assembly 102 is immediately adjacent and minimally spaced from the
second tool assembly 104. That is, as the first tool assembly 102
moves from the first position to the second position, the forming
punch 108 engages and deforms blank 1 and forms the blank into a
formed blank 10. As is known, the tooling assembly 100, in one
embodiment, is supplied with pre-cut blanks 1 to be formed into
cups 2. In another embodiment, the tooling assembly 100 is supplied
with a sheet of material (not shown) and cuts blanks 1 from the
sheet as part of the forming operation.
[0056] The following disclosure details the formation of a cup 2
which is then formed into a can body 5, as is generally known. The
cup 2, and the subsequent can body 5, hereinafter and collectively
the formed blank 10, includes a truncated protrusion 20, as shown
in FIGS. 5A and 5B. Initially, however, the following disclosure
details the configuration of the finished formed blank 10. That is,
the formed blank 10 includes a body 11 having a base 12 and a
depending sidewall 14. Further, as is known, a can body base 12
includes a ridge 16 extending about the base 12. In an exemplary
embodiment, the base 12 is generally circular and, as such, the
depending sidewall 14 is generally cylindrical and the ridge 16 is
an annular ridge 16'. Further, in an exemplary embodiment, the
truncated protrusion 20 is a truncated dome 22. That is, the base
12 includes a truncated protrusion 20 including a number of
generally curvilinear portion(s) 30 and a generally planar portion
32. It is noted that the cup 2 shown in FIG. 5A has a single bead
(not numbered) and is a cup 2 for a beverage can body 5A.
Conversely, the cup shown in FIG. 9A (not numbered) has two beads
and is for a food can body 5B. Generally, a cup 2 for a food can
body 5B has a greater diameter than a cup 2 for a beverage can body
5A and, as such, can accommodate another bead.
[0057] Further, compared to a generally hemispherical dome, i.e., a
generally arcuate dome when viewed in cross-section, a truncated
dome 22 has a "reduced volume." As used herein, a "reduced volume"
means a protrusion formed in the bottom of a cup, such as, but not
limited to, a truncated dome that has a reduced volume of metal
compared to a generally hemispherical dome, i.e., a generally
arcuate dome when viewed in cross-section. It is noted that the
length of the bottom profile (when viewed in cross-section as shown
in FIG. 5A) of a truncated dome 22, i.e., the length from the outer
edge of the truncated dome 22 to the center of the truncated dome
22 is shorter than the length of a generally hemispherical dome
because the generally planar portion 32 of a truncated dome 22 has
a shorter length relative to an arc on a generally hemispherical
dome. Stated alternately, when an arc within and confined by a
perimeter, e.g., sidewalls 14 (when viewed in cross-section), is
flattened to a generally straight line, the length of the now
flattened line is shorter relative to the previously existing arc.
Thus, as this distance is shorter, the volume of the truncated dome
22 is less than a generally hemispherical dome having the same
diameter.
[0058] In one exemplary embodiment, not shown, there is a single
curvilinear portion 30 that extends between the annular ridge 16'
and the generally planar portion 32. Further, the single
curvilinear portion 30 is, in an exemplary embodiment, an arcuate
portion 40. As used herein, the term "arcuate portion" refers to
the shape of the truncated protrusion 20 when viewed in
cross-section, as shown in FIG. 5A; it is understood that the
curvilinear portion 30 (or arcuate portion 40) when rotated about
an axis in three dimensions forms a dome, or dome-like, shape. In
the embodiment shown, the number of generally curvilinear
portion(s) 30 includes a first generally curvilinear portion 34 and
a second generally curvilinear portion 36. The truncated dome first
generally curvilinear portion 34 has a first center, and, the
truncated dome second generally curvilinear portion 36 has a second
center. As used herein, the "center" of a curvilinear line means a
point that is disposed generally an equal distance from all points
on the curvilinear line; for an arcuate line, the "center" means a
point that is disposed substantially an equal distance from all
points on the arcuate line. In an exemplary embodiment, the first
generally curvilinear portion 34 and the second generally
curvilinear portion 36 are a first generally arcuate portion 44 and
a second generally arcuate portion 46, respectively.
[0059] Further, as discussed in more detail below, a portion of the
truncated protrusion 20 (or truncated dome 22) is stretched
(hereinafter the "stretched portion" 38) during the forming process
so that the material forming the truncated protrusion 20, or a
portion of the truncated protrusion 20, is thinner than the base
gauge of the original material, i.e., the base gauge of the blank 1
which, in an exemplary embodiment, is also the thickness of the
sidewall 14. In an exemplary embodiment, substantially all of the
truncated protrusion 20 (or truncated dome 22) has a uniform
thickness. That is, in one exemplary embodiment, the stretched
portion 38 extends over substantially all of the curvilinear
portion(s) 30 (34, 36) as well as the planar portion 32. In other
embodiments, the stretched portion 38 extends over only a portion
of the curvilinear portion(s) 30 (34, 36) and/or the planar portion
32. Further, in an exemplary embodiment, the truncated protrusion
20 (or truncated dome 22) has a thickness that is between about
0.0003 inch and 0.002 inch thinner than the base gauge of the
original material and/or the sidewall 14.
[0060] Generally, the tooling and method of forming a cup 2 or can
body 5 with a stretched dome is disclosed in U.S. patent
application Ser. No. 15/286,954. The following disclosure addresses
the details of the tooling assembly 100, shown in FIG. 6, and
method (FIG. 10) for forming a truncated protrusion 20 (or
truncated dome 22). As noted above, the tooling assembly 100
includes a first tool assembly 102 and a second tool assembly 104
structured to form a blank 1 into formed blank 10, i.e. , a cup 2
or a can body 5. It is noted that the blank 1 has a base gauge
(thickness) and that, after the initial formation of the formed
blank 10, the base 12 and the sidewall 14 have substantially the
same thickness as the base gauge. Further, in an exemplary
embodiment, the tooling assembly 100 is structured to, and does,
maintain the thickness of the sidewall 14 substantially at the base
gauge.
[0061] The first tool assembly 102 and second tool assembly 104 are
further structured to, and do, clamp the blank 1 of material at the
periphery of the base 12. In an exemplary embodiment, the periphery
of the base 12 is defined by the ridge 16; thus, the first tool
assembly 102 and second tool assembly 104 are further structured
to, and do, clamp the blank 1 of material at the ridge 16. The
first tool assembly 102 and the second tool assembly 104 are
structured to, and do, stretch a portion of the base 12 and thereby
thin the base stretched portion 38 relative to the base gauge of
the material and/or the sidewall 14. As discussed above, the
stretched portion 38, in an exemplary embodiment, has a generally
uniform thickness. Further, in an exemplary embodiment, the
stretched portion 38 is coextensive with the entire base 12. To
accomplish this, the formed blank 10 is moved by the forming punch
108 to the forming die 110. The forming punch 108, in this
embodiment, is an elongated, generally cylindrical body 112 with a
cavity 114 at the distal end. The cavity 114, in one embodiment, is
generally concave and contoured to correspond to the shape of a
forming surface 120, discussed below. In another embodiment, the
cavity 114 is generally cylindrical; that is, the forming punch 108
is generally hollow.
[0062] As shown in FIG. 6, the forming surface 120 is disposed on
the forming die 110 of the second tool assembly 104. In an
exemplary embodiment, the forming die 110 remains substantially
stationary relative to the forming punch 108. That is, the forming
punch 108 reciprocates in a generally vertical direction and the
upper surface of the forming die 110 has a convex protrusion 111
that defines the forming surface 120. The forming surface 120
includes a truncated protrusion forming profile 122. Thus, the
forming punch 108 is structured to, and does, move the blank 1 of
material into contact with the truncated protrusion forming profile
122. In an exemplary embodiment, the truncated protrusion forming
profile 122 is a truncated dome forming profile 122'.
[0063] The truncated dome forming profile 122' includes a number of
generally curvilinear portions 126 and a planar portion forming
construct 128. To form a truncated dome 22 as described above, the
truncated dome forming profile number of generally curvilinear
portions 126 includes a first generally curvilinear portion 130 and
a second generally curvilinear portion 132. The truncated dome
forming profile first generally curvilinear portion 130 has a first
center 134 and the truncated dome forming profile second generally
curvilinear portion 132 has a second center 136. Further, in an
exemplary embodiment, the truncated dome forming profile first
generally curvilinear portion 130 is a first generally arcuate
portion 140, and, the truncated dome forming profile second
generally curvilinear portion 132 is a second generally arcuate
portion 142.
[0064] The truncated dome forming profile planar portion forming
construct 128 is in one exemplary embodiment, not shown, a
generally planar surface. That is, the truncated dome forming
profile 122' is generally flat at the vertex. In the embodiment
shown, the truncated dome forming profile planar portion forming
construct 128 is a cavity 150. That is, the truncated dome forming
profile 122' is defined by the number of generally curvilinear
portions 126. The truncated dome forming profile planar portion
forming construct is the cavity 150 in the die. Stated alternately,
the number of generally curvilinear portions 126 extend generally
concentrically about a cavity 150.
[0065] In this configuration, the formed blank 10, and more
specifically the base 12, is clamped between the first tool
assembly 102 and the second tool assembly 104 as it is moved into
the forming die 110. As the forming punch 108 moves the base 12
over the truncated dome forming profile 122', the material of the
base 12 is stretched and thinned. Further, the material of the base
12 is formed to the contour of the truncated dome forming profile
122'. That is, a portion of the base 12 is formed to the truncated
dome forming profile first generally curvilinear portion 130 and
the truncated dome forming profile second generally curvilinear
portion 132. Further, as the center of the forming die 110 is
hollow (and as the forming punch 108 is also hollow) the center of
the base 12 remains generally planar while being thinned. In an
exemplary embodiment, the first tool assembly 102 and the second
tool assembly 104 are structured to form the formed blank sidewall
14 with a thickness about the same as the base gauge. The first
tool assembly 102 and the second tool assembly 104 are also
structured to form the formed blank truncated protrusion with a
thickness that is less than the formed blank sidewall 14. In an
exemplary embodiment, the first tool assembly 102 and the second
tool assembly 104 are structured to form the formed blank truncated
protrusion 20 with a thickness that is between about 0.0003 inch
and 0.002 inch thinner than the formed blank sidewall 14.
[0066] Thus, as shown in FIG. 10, a method of forming a formed
blank within a tooling assembly 100, as described above, includes
forming 1000 a blank 1 of material to include a base 12 and a
depending sidewall 14, clamping 1002 the blank 1 between the first
tool assembly 102 and the second tool assembly 104 at the periphery
of the base 12, and stretching 1004 the base 12, thereby thinning a
portion of the base 12 relative to the sidewall 14 to form a
stretched portion 38. In an exemplary embodiment, stretching 1004
the base 12, thereby thinning a portion of the base 12 relative to
the sidewall 14 to form a stretched portion 38 includes stretching
1006 the base stretched portion so as to have a generally uniform
thickness. Further, stretching 1004 the base 12, thereby thinning a
portion of the base 12 relative to the sidewall 14 to form a
stretched portion 38 includes forming 1010 a truncated protrusion
20. In an exemplary embodiment, forming 1010 a truncated protrusion
20 includes forming 1012 a truncated dome 22.
[0067] To form the truncated dome 22 described above, forming 1012
a truncated dome includes: forming 1020 a dome with a first
generally curvilinear portion and a second generally curvilinear
portion, forming 1022 the first generally curvilinear portion about
a first center, and forming 1024 the second generally curvilinear
portion about a second center. Further, to form the truncated dome
22 described above forming 1000 the blank 1 of material to include
a base 12 and a depending sidewall 14 includes forming 1030 the
sidewall 14 with a thickness generally corresponding to the base
gauge of the material. Further, stretching 1004 the base 12,
thereby thinning a portion of the base 12 relative to the sidewall
14 includes forming 1032 the stretched portion 38 with a thickness
that is less than the formed blank sidewall 14. Further, in an
exemplary embodiment, stretching 1004 the base 12, thereby thinning
a portion of the base 12 relative to the sidewall 14 includes
forming 1036 the stretched portion 38 with a thickness that is
between about 0.0003 inch and 0.002 inch thinner than the sidewall
14.
[0068] The process described above discloses forming a blank 1 into
a cup 2 having a truncated protrusion 20. It is understood that
such a cup 1 is then formed into a can body 5 either in the same
device or the cup 2 is transported to a bodymaker, as is known. The
can body 5 made from such a cup 2 also includes the truncated
protrusion 20. Alternatively, when forming the cup 1 into a can
body 5, the thinned portion is reformed into a traditional dome
that is generally concave; i.e., the dome 9 does not have a
generally planar portion. As used herein, a can body 5 made from a
cup 2 having a truncated protrusion 20 is also a formed blank 10
having a truncated protrusion 20 regardless of whether the
truncated protrusion 20 is reformed at a later stage of
processing.
[0069] That is, as shown in FIGS. 8A-8E, cup 2 with a truncated
protrusion 20 is formed into a beverage can body 5'. That is, as
shown in FIGS. 8A-8C, the cup 2 is reformed by inverting the
truncated protrusion 20. During this forming process, the bottom of
the cup 2 is reformed so as to be substantially planar. Thus, as
shown in FIGS. 8D and 8E, when the can beverage can body 5' is
reformed with a dome, the bottom of the cup 2 forms over the domer
180 with no loose metal as in the prior art.
[0070] Similarly, FIGS. 9A-9E show the formation of a food can body
5''. In this process, the cup 2 and the truncated protrusion 20 are
reformed as substantially planar elements. Because the generally
planar portion 32 is already generally planar, the reformed can
body does not include an offset portion which is a remnant of the
dome.
[0071] While specific embodiments of the invention have been
described in detail, it will be appreciated by those skilled in the
art that various modifications and alternatives to those details
could be developed in light of the overall teachings of the
disclosure. Accordingly, the particular arrangements disclosed are
meant to be illustrative only and not limiting as to the scope of
invention which is to be given the full breadth of the claims
appended and any and all equivalents thereof.
* * * * *