U.S. patent application number 10/346778 was filed with the patent office on 2003-06-19 for method of forming articles of manufacture of various shapes including undercuts therein with generic tool.
This patent application is currently assigned to Batesville Services, Inc. of One Batesville Boulevard. Invention is credited to Laphan, Dennis C., Rojdev, Ilija.
Application Number | 20030111769 10/346778 |
Document ID | / |
Family ID | 23814247 |
Filed Date | 2003-06-19 |
United States Patent
Application |
20030111769 |
Kind Code |
A1 |
Laphan, Dennis C. ; et
al. |
June 19, 2003 |
Method of forming articles of manufacture of various shapes
including undercuts therein with generic tool
Abstract
A method of forming an article of manufacture which includes an
undercut therein comprises the steps of providing a tool, removably
positioning at least one consumable form adjacent to the tool,
providing settable material from which to mold a finished part,
molding the material onto the tool and on the form so as to
encapsulate the form within the material to thereby form an
undercut therein, allowing the material to set to form the finished
part and separating the tool from the finished part and the
encapsulated form. A method is also provided for forming articles
of manufacture of various configurations utilizing a single generic
tool by repeating the steps with differently shaped forms removably
affixed to the single generic tool in different locations to
produce a plurality of finished parts of varying configurations
with the single generic tool.
Inventors: |
Laphan, Dennis C.;
(Cincinnati, OH) ; Rojdev, Ilija; (Fairfield,
OH) |
Correspondence
Address: |
Wood, Herron & Evans
2700 Carew Tower
Cincinnati
OH
45202
US
|
Assignee: |
Batesville Services, Inc. of One
Batesville Boulevard
Batesville
IN
|
Family ID: |
23814247 |
Appl. No.: |
10/346778 |
Filed: |
January 17, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10346778 |
Jan 17, 2003 |
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09304779 |
May 4, 1999 |
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6530134 |
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09304779 |
May 4, 1999 |
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08456813 |
Jun 1, 1995 |
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5928599 |
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Current U.S.
Class: |
264/318 |
Current CPC
Class: |
A61G 17/0136 20170501;
B29C 51/12 20130101; B29C 2791/006 20130101; B29C 51/10
20130101 |
Class at
Publication: |
264/318 |
International
Class: |
B29C 045/14 |
Claims
What is claimed is:
1. A method of forming an article of manufacture including an
undercut therein comprising the steps of: providing a tool;
removably positioning at least one consumable form adjacent to the
tool; providing settable material from which to mold a finished
part; molding the material on the tool including on the form so as
to encapsulate the form within the material to thereby form an
undercut therein; allowing the molded material to set to form the
finished part; and separating the tool from the finished part and
the encapsulated form.
2. The method of claim 1 wherein the settable material is
plastic.
3. The method of claim 1 wherein the settable material is a
composite.
4. The method of claim 2 wherein the plastic is preformed into a
blank.
5. The method of claim 4 wherein the blank is a tub.
6. The method of claim 4 wherein the blank is a sheet.
7. The method of claim 4 wherein the plastic blank is vacuum molded
onto the tool and form.
8. The method of claim 7 wherein the finished part is a casket.
9. The method of claim 1 wherein the form includes fasteners
premounted thereon whereby hardware may be attached to the form
fasteners after molding the material onto the tool and form.
10. The method of claim 1 wherein the form is colored and the
material is translucent whereby the color of the form is visible
through the translucent material.
11. The method of claim 1 wherein the form is textured whereby the
texture of the form is visible through the material.
12. A method of forming an article of manufacture including a
skeletal structural framework therein comprising the steps of:
providing a tool; removably positioning at least one consumable
form adjacent to the tool; providing a settable material from which
to mold a finished part; molding the material on the tool including
on the form so as to encapsulate the form within the material to
thereby form a skeletal structural framework therein; allowing the
molded material to set to form the finished part; and separating
the tool from the finished part and the encapsulated form.
13. The method of claim 12 wherein the settable material is
plastic.
14. The method of claim 12 wherein the settable material is a
composite.
15. The method of claim 13 wherein the plastic is preformed into a
blank.
16. The method of claim 15 wherein the blank is a tub.
17. The method of claim 15 wherein the blank is a sheet.
18. The method of claim 15 wherein the plastic blank is vacuum
molded onto the tool and form.
19. The method of claim 18 wherein the finished part is a
casket.
20. The method of claim 13 wherein the form includes fasteners
premounted thereon whereby hardware may be attached to the form
after molding the material onto the tool and form.
21. The method of claim 13 wherein the form is colored and the
material is translucent whereby the color of the form is visible
through the translucent material.
22. The method of claim 12 wherein the form is textured whereby the
texture of the form is visible through the material.
23. A method of forming articles of manufacture of various
configurations utilizing a single generic tool comprising the steps
of: providing a single generic tool; removably positioning at least
one consumable form adjacent to the tool; providing settable
material from which to mold a finished part; molding the material
on the tool including on the form so as to encapsulate the form
within the molded material to thereby define a specific
configuration for the finished part; allowing the molded material
to set to form the finished part; separating the tool from the
finished part and the encapsulated form; and repeating the above
steps with differently shaped forms removably affixed to the single
generic tool in different locations to produce a plurality of
finished parts of varying configurations with the single generic
tool.
24. The method of claim 23 wherein the settable material is
plastic.
25. The method of claim 23 wherein the settable material is a
composite.
26. The method of claim 24 wherein the plastic is preformed into a
blank.
27. The method of claim 26 wherein the blank is a tub.
28. The method of claim 26 wherein the blank is a sheet.
29. The method of claim 26 wherein the plastic blank is vacuum
molded onto the tool and form.
30. The method of claim 29 wherein the finished part is a
casket.
31. The method of claim 23 wherein the form includes fasteners
premounted thereon whereby hardware may be attached to the form
fasteners after molding the material onto the tool and form.
32. The method of claim 23 wherein the form is colored and the
material is translucent whereby the color of the form is visible
through the translucent material.
33. The method of claim 23 wherein the form is textured whereby the
texture of the form is visible through the material.
34. An article of manufacture formed by the method of claim 1, 12
or 23.
35. A method of vacuum molding a plastic casket comprising the
steps of: providing a rectangular tool generally in the size of a
casket; removably positioning consumable forms around the periphery
of the tool adjacent to the tool; providing a plastic blank from
which to mold the plastic casket; heating the plastic blank to
soften the blank; vacuum molding the plastic blank on the tool
including on the forms so as to encapsulate the forms within the
molded blank; allowing the molded blank to set to form the casket;
and separating the tool from the casket and the encapsulated
forms.
36. The method of claim 35 wherein the blank is a tub.
37. The method of claim 35 wherein the blank is a sheet.
38. The method of claim 37 wherein the tool has side, end and
bottom walls and is inverted and wherein the form has a generally
L-shape cross-section having a foot and a leg, and wherein the foot
of the form is supported atop the bottom of the tool.
39. A plastic casket formed by the method of claim 35.
40. A method of vacuum molding a plastic casket comprising the
steps of: providing a rectangular tool having side, end and bottom
walls and generally in the size of a casket; removably positioning
consumable forms adjacent to the tool around the periphery of the
tool; providing a plastic sheet from which to mold the plastic
casket; supporting the sheet in a rectangular frame; applying heat
to the sheet to soften the sheet; moving the frame over the tool so
as to move the sheet adjacent the tool side, end and bottom walls;
applying vacuum between the sheet and tool so as to vacuum mold the
sheet on the tool including on the forms so as to encapsulate the
forms within the molded sheet; allowing the molded sheet to set to
form the casket; and removing the casket with encapsulated forms
from tool.
41. The method of claim 40 wherein the forms are hollow and further
comprising the step of injecting structural foam into the forms
thereby creating a unitized form structure about the periphery of
the casket.
42. A plastic casket formed by the method of claim 40.
Description
FIELD OF THE INVENTION
[0001] This invention relates generally to the production of molded
articles of manufacture, and more particularly to the production of
molded plastic or composite articles of manufacture.
BACKGROUND OF THE INVENTION
[0002] Traditional methods of molding parts, for example plastic or
composite parts, by vacuum molding, sheet compound molding,
reaction injection molding, injection molding and/or rotational
molding have heretofore required an expensive, complex and specific
tool with which to form a particular molded part shape. Thus,
should a plurality of shapes of molded parts be desired or
required, a separate, specific tool is required to fabricate each
specifically shaped part, thus substantially increasing the costs
to manufacturers.
[0003] Further, should a manufacturer desire to include features
such as undercuts in a molded part, expensive, complicated
collapsible tooling is required to remove the tool from the molded
part in the area of the undercut. Such expensive, complicated
tooling generally must include a complex system of slides and ways
to accomplish such collapsing to remove the tool from the formed
part. Thus, manufacturers have either had to purchase or construct
such complex tooling in order to form undercuts in their molded
parts, or have simply had to forego such undercuts and in the
process do without the substantial functional and aesthetic
benefits and attributes attributable to such undercuts.
[0004] It is therefore one objective of the present invention to
provide a method of forming an article of manufacture including
undercuts therein which does not require the use of expensive,
complicated collapsible tooling to accomplish the formation of the
undercuts in the part.
[0005] It is another objective of the present invention to provide
a method of forming articles of manufacture of various
configurations utilizing only a single generic tool rather than a
plurality of specific tools fabricated for each specific part
configuration.
SUMMARY OF THE INVENTION
[0006] The present invention attains the stated objectives by
providing a method of forming an article of manufacture including
an undercut therein. The method comprises providing a tool,
removably positioning at least one consumable form adjacent to the
tool, providing settable material from which to mold a finished
part, molding the material on the tool including on the form so as
to encapsulate the form within the molded material to thereby form
an undercut therein, allowing the molded material to set to form
the finished part, and separating the tool from the finished part
and the encapsulated form.
[0007] The settable material may be plastic. The plastic material
may be a preformed blank in the form of a sheet or tub. The sheet
or tub may be vacuum molded onto the tool and form. The finished
part may be a casket or many other articles of manufacture.
[0008] According to another aspect of the present invention, the
form includes fasteners premounted thereon whereby cooperating
hardware may be attached to the form fasteners after molding the
plastic material onto the tool and form. In the case of caskets,
the premounted form fasteners or hardware may be used to attach
casket handling hardware. The premounted form fasteners could be
used for a variety of other purposes for example as attachment
sites for additional components, containers, electrical or fluid
connectors etc.
[0009] According to yet another aspect of the present invention,
the form is colored and/or textured and the material is translucent
whereby the color and/or texture of the form is visible through the
translucent material.
[0010] In still another aspect of the present invention, a method
of forming articles of manufacture of various configurations
utilizing a single generic tool is provided. The method comprises
the steps of providing a single generic tool, removably positioning
at least one consumable form adjacent to the tool, providing
settable material from which to mold a finished part, molding the
material on the tool including on the form so as to encapsulate the
form within the molded material to thereby define a specific
configuration for the finished part, allowing the molded material
to set to form the finished part, separating the tool from the
finished part and the encapsulated form, and repeating the above
steps with differently shaped forms removably affixed to the single
generic tool in different locations to produce a plurality of
finished parts of varying configurations with the single generic
tool.
[0011] One advantage of the present invention is that a method of
forming an article of manufacture is provided wherein undercuts may
be readily included in the shape of the finished part, yet without
having to employ the use of expensive, complicated and complex
collapsible tools which incorporate slides and ways.
[0012] Another advantage of the present invention is that a method
of forming articles of manufacture of various shapes with a single
generic tool is provided thereby obviating the need to have a
specific, custom tool manufactured to produce each differently
shaped finished part.
[0013] These and other objects and advantages of the present
invention will become more readily apparent during the following
detailed description taken in conjunction with the drawings herein,
in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a fragmentary perspective view of a generic tool
including consumable forms thereon utilized in the fabrication of
an article of manufacture according to the principles of the
present invention;
[0015] FIG. 2 is a cross-sectional view of the tool and forms of
FIG. 1 inserted into a preformed plastic tub blank;
[0016] FIG. 3 is a view similar to FIG. 2 illustrating the plastic
tub being heated and vacuum molded to the tool and forms during
heating of the blank;
[0017] FIG. 4 is a view similar to FIGS. 2 and 3 illustrating the
tool being removed from the finished molded part and from the
encapsulated forms;
[0018] FIG. 5 is a view similar to FIGS. 2-4 of the finished part
with encapsulated forms;
[0019] FIG. 6 is a view similar to FIG. 2 but of a different
process for carrying out the invention wherein the tool is inverted
and a preformed plastic sheet blank is positioned above the tool
and is heated to be subsequently drawn down over the tool;
[0020] FIG. 7 is a view similar to FIG. 6 illustrating the sheet
drawn down over the tool;
[0021] FIG. 8 is a view similar to FIGS. 6 and 7 illustrating the
sheet being vacuum molded to the tool and forms; and
[0022] FIG. 9 is a view of the finished part with encapsulated
forms removed from the tool.
DETAILED DESCRIPTION OF THE INVENTION
[0023] Referring first to FIG. 1, there is illustrated a generic
tool 10 utilized in forming an article of manufacture according to
the principles of the present invention. The generic tool 10 as
illustrated is generally rectangular in shape and may be sized
appropriately depending on the specific part to be fabricated.
Other shapes may be utilized for other applications. For example,
one specific application of the present invention is in the
fabrication of caskets; tool 10 would thus be sized
accordingly.
[0024] The generic tool 10 includes a pair of end walls, one of
which is shown at 12, and a pair of side walls, one of which is
shown at 14. The tool may also include a top wall 16 which may form
a part of a "vacuum box" and a bottom wall (not shown). The side
and end walls 12 and 14 include a plurality of holes 20 which are
in fluid communication with an outlet 22 which is to be connected
to a vacuum source for vacuum molding a part on the tool 10. While
tool 10 is illustrated as being a male tool for forming thereon a
female part, it will be appreciated that the principles of the
present invention could as well be employed with a female tool in
the production of a male part, for example bath tubs, spas etc.
[0025] A plurality of forms 30 are removably positioned adjacent to
the side and end walls 12 and 14 of the tool 10. The forms 30 may
have any particular cross sectional configuration which is desired,
and preferably are fabricated from inexpensive, light weight and
stiff material such as structural foam, wood, plastic extrusions or
the like. The forms 30 may be removably secured to the side and end
walls 12 and 14 of the tool 10 by such means as low shear strength
adhesives, double-sided tape, magnetics, a separate vacuum box,
cylinders, pins or the like. Alternatively, a free standing system
could be employed for positioning the forms adjacent the tool.
[0026] Referring now to FIG. 2, a preformed blank 40 of a settable
material, for example plastic, which, as illustrated, is a
generally rectangular-shaped tub, may be supported in a fixture 42.
The tool 10 with forms 30 thereon is inserted into the blank 40 as
is illustrated.
[0027] Referring now to FIG. 3, heat is applied from a heat source
to the walls of the tub 40 to soften the plastic, while at the same
time the vacuum source applies a vacuum to the tool 10 and through
holes 20 thus vacuum forming or molding the softened plastic tub
blank 40 to the side and end walls 12 and 14 and bottom of the tool
10 and at the same time encapsulating the consumable forms 30.
[0028] Once the plastic is allowed to cool and sets up, the tool 10
may be removed from the finished part by simply pulling the tool
out of the part as is shown in FIG. 4. The tool simply shears away
from the forms 30 which have been encapsulated, or otherwise
consumed, in the finished plastic part.
[0029] A preferable material from which to form the preformed
blank, and hence the final part, as mentioned above, may be
plastic, but other settable materials which are at one point soft
and subsequently harden or set up may also be employed. Further,
while vacuum molding may be the preferred method of molding the
part, other methods of molding or forming may also be utilized in
the practice of the present invention, for example such as
injection molding, rotational molding, sheet compound molding,
reaction injection molding and pressure forming. Preformed blank
shapes other than the preformed tub illustrated may be utilized
such as simple sheets etc.
[0030] One particular product which lends itself to fabrication
from the present invention as is mentioned above is a plastic
casket, though many other articles of manufacture may be fabricated
according to the principles of the present invention, such as, for
example, automotive body panels, bathroom tubs and shower stalls,
hot tubs, swimming pools, casket vaults, boats and the like, the
invention therefore not being limited to the production of
caskets.
[0031] An alternative method of attaching forms to the tool is to
invert the tool and place a form having a generally L-shaped
configuration on the tool edge formed by the tool side and bottom
walls and the tool end and bottom walls, whereby the form is held
in place on the tool simply by gravity.
[0032] In the production of caskets, the forms 30 may include
premounted therein fasteners whereby casket handling hardware may
be attached to the form fasteners after molding the plastic blank
onto the tool and form. For example, a plurality of nuts could be
pressed or otherwise mounted in the forms, and once the plastic
casket is formed, one would need only to pierce the plastic casket
skin over the nut for threadably engaging the nut with, for
example, a threaded bolt to secure casket handling hardware to the
casket exterior. Other applications for other products include
providing attachment sites for additional components, electrical
and/or fluid connections and the like.
[0033] The forms 30 also readily lend themselves to being brightly
colored, which, when utilized with a translucent or transparent
plastic to form the casket, will be visible through to the exterior
of the casket thereby providing a decorative, ornamental
appearance. In addition, the forms 30 could be textured whereby the
texture of the form would print through or otherwise be visible
through the plastic. The colored and/or textured forms could be
utilized in the production of other articles of manufacture other
than caskets as well.
[0034] A further advantage of fabricating articles of manufacture
according to the principles of the present invention is that the
invention readily provides for the inclusion of a skeletal
structural framework within the article thereby providing for
additional stiffness and strength of the article and consequent
ability to reduce the skin thickness of the plastic. The forms
could be solid or hollow. If hollow, the forms could be filled with
structural foam providing contiguous or continuous forms thereby
unitizing the forms and improving the strength characteristics. The
filling of the forms with structural foam can be accomplished with
an injection orifice contained within the tool.
[0035] The method of the present invention also readily lends
itself to the formation of articles of manufacture of various
configurations but utilizing only a single generic tool. In this
aspect, a first article of manufacture is fabricated according to
the above-described steps in reference to the Figures. Then, those
same steps can be repeated, but with differently shaped forms
removably affixed to the single generic tool in different locations
thereby to produce a plurality of finished parts of varying
configurations with the single generic tool.
[0036] Referring now to FIGS. 6-9, there is illustrated a preferred
technique for vacuum molding an article of manufacture according to
the present invention. In FIG. 6, tool 100 is inverted and has a
bottom 102, sides 104 and a top or vacuum box 106 connectable to a
source of vacuum. A rectangular frame 110 clamps and supports a
rectangular sheet of plastic 112 around its periphery. Heat is
applied to the sheet 112 from a source of heat 113 to soften the
sheet 112. A form 114 which is generally L-shaped in cross-section
has a leg 116 and a foot 118. Foot 118 is supported atop the bottom
102 of the tool 100. As tool 100 is inverted, the casket or other
article of manufacture fabricated by vacuum molding sheet 112 to
tool 100 will have the forms 114 associated with the bottom edge of
the article of manufacture. Another form 120 includes an aperture
122 therein which accepts the foot 124 of an L-shaped bracket 126
which is attached to tool 100. L-shaped bracket 126 may be fixed to
tool 100 or may be removably attached and adjustably repositionable
relative thereto as with the use of pins or other means of
attachment to vary the position of form 120 relative to form
114.
[0037] As illustrated in FIG. 7, as rectangular frame 110 is drawn
downwardly over the tool 100, sheet 112 assumes the general
rectangular configuration of the tool 100. As shown in FIG. 8, when
vacuum is applied from the source of vacuum 128, the sheet 112
closely conforms to the tool 100 and the forms 114 and 120. As
shown in FIG. 9, once the plastic sheet has been allowed to cool
and set to form the plastic casket, the casket is removed from the
tool 100 and the frame 110 is removed from the finished part.
[0038] Those skilled in the art will readily recognize numerous
adaptations and modifications which can be made to the present
invention which will result in an improved method of forming
articles of manufacture, yet all of which will fall within the
spirit and scope of the present invention as defined in the
following claims. For example the settable plastic material would
not have to be preformed into a sheet or tub blank as when
utilizing the invention in conjunction with an injection molding
technique. Accordingly, the invention is to be limited only by the
scope of the following claims and their equivalents.
* * * * *