U.S. patent application number 10/639766 was filed with the patent office on 2005-09-01 for method and apparatus for manufacturing molded products.
This patent application is currently assigned to Lund International, Inc.. Invention is credited to Ferreira, Antero, Ferreira, Fernando A., Neri, Stephen P..
Application Number | 20050191459 10/639766 |
Document ID | / |
Family ID | 22712774 |
Filed Date | 2005-09-01 |
United States Patent
Application |
20050191459 |
Kind Code |
A1 |
Ferreira, Fernando A. ; et
al. |
September 1, 2005 |
Method and apparatus for manufacturing molded products
Abstract
The present invention provides apparatuses and methods for
producing molded products such as floor mats, including automotive
floor mats. In one embodiment, a molding process is provided for
producing a molded product using a mold having a lower plate and an
upper plate. The molding process includes steps of filling a first
cavity of the lower plate with a liquid molding material of a first
color, placing the upper plate on top of the lower plate such that
a convex portion of the upper plate extends into the first cavity
of the lower plate and contacts the molding material in the lower
plate, and curing the liquid molding material.
Inventors: |
Ferreira, Fernando A.;
(Bristol, RI) ; Ferreira, Antero; (Bristol,
RI) ; Neri, Stephen P.; (Hope Valley, RI) |
Correspondence
Address: |
MERCHANT & GOULD PC
P.O. BOX 2903
MINNEAPOLIS
MN
55402-0903
US
|
Assignee: |
Lund International, Inc.
Anoka
MN
|
Family ID: |
22712774 |
Appl. No.: |
10/639766 |
Filed: |
August 11, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10639766 |
Aug 11, 2003 |
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09804019 |
Mar 12, 2001 |
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6605333 |
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09804019 |
Mar 12, 2001 |
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09193236 |
Nov 17, 1998 |
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6221298 |
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Current U.S.
Class: |
428/95 ; 15/216;
15/217; 428/156; 428/167; 428/169; 428/172 |
Current CPC
Class: |
B29C 39/023 20130101;
B29C 43/021 20130101; Y10T 428/2457 20150115; B29D 99/0057
20130101; Y10T 428/24479 20150115; Y10T 428/24612 20150115; B29C
33/10 20130101; B29C 35/00 20130101; Y10T 428/23979 20150401; B29L
2031/3017 20130101; Y10T 428/24587 20150115 |
Class at
Publication: |
428/095 ;
428/156; 428/167; 428/169; 428/172; 015/216; 015/217 |
International
Class: |
B32B 003/30; A47L
023/22 |
Claims
1-27. (canceled)
28. A floor mat comprising a top surface and a bottom surface and
having features provided in both the top surface and the bottom
surface, wherein: (a) the floor mat comprises a result of molding
and curing a molding material between a lower plate for forming the
top surface of the floor mat and an upper plate for forming the
bottom surface of the floor mat; (b) at least a portion of the
features in the bottom surface comprise nubs formed as a result of
the molding material flowing through a plurality of air holes in
the bottom plate.
29. A floor mat according to claim 28, wherein the features in the
top surface comprise a pattern of ridges.
30. A floor mat according to claim 28, wherein the features in the
top surface comprise a plurality of wells.
31. A floor mat according to claim 28, wherein the features of the
bottom surface comprise a plurality of recessed portions and a
plurality of non-recessed portions, and the plurality of nubs
extend from the non-recessed portions.
32. A floor mat according to claim 28, wherein the top surface
includes a plurality of concentric raised ridges.
33. A floor mat according to claim 30, wherein the wells on the top
surface are generally octagonal.
34. A floor mat according to claim 28, wherein the nubs are
generally cylindrical.
35. A floor mat according to claim 31, wherein the nubs are
uniformly spaced around the recessed portions of the bottom
surface.
36. A floor mat according to claim 31, wherein the recesses on the
bottom surface have a generally pyramid shape including four base
edges and four corner points, and wherein nubs are located at the
corner points.
37. A floor mat according to claim 28, further comprising a carpet
attached to the top surface.
38. A floor mat according to claim 28, wherein the top surface
further includes: a front section; a heel section; and a rear
section.
39. A floor mat according to claim 38, wherein the heel section
includes a plurality of raised ribs separated by a plurality of
channels.
40. A floor mat according to claim 39, wherein the plurality of
raised ribs substantially forms a herringbone pattern.
41. A floor mat according to claim 38, wherein carpet is retained
in the front section and the rear section.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to a method and
apparatus for manufacturing molded products. More specifically,
embodiments of the present invention relate to an open-pore molding
process and apparatus for manufacturing molded products. In
addition, embodiments of the present invention are directed to
molded products, including floor mats, manufactured using processes
of the present invention.
BACKGROUND OF THE INVENTION
[0002] Open-pore or open cavity molding processes for manufacturing
molded rubber or plastic products are known. In a typical prior art
open cavity molding process, a single piece mold having a concave
portion formed therein is filled with a liquid rubber or plastic
material, and the mold is inserted in an oven to cure the material.
After curing, the finished product is removed from the mold. These
open cavity molding processes of the prior art are relatively
inexpensive and are particularly useful for manufacturing
substantially flat thin products including floor mats, such as
those typically used in automobiles and other vehicles. In typical
open cavity molding processes, a single color of material is used
to make single color products.
[0003] Products manufactured using open cavity molding processes
typically have one smooth side, formed from the top surface of the
material in the mold, and one featured side having a number of
contoured features formed therein by contours in the bottom surface
of the concave portion of the mold. For typical floor mats
manufactured using the prior art processes described above, the
bottom surface of the floor mat is substantially smooth, and the
top surface has a number of contours or features that provide a
textured surface.
[0004] For floor mats and other products, it is sometimes desirable
to have features formed on the top and bottom surfaces of the
products, and to provide products having multiple colors. While it
is possible to produce such products using processes other than
open cavity molding, such as injection molding, these other
processes are typically more complex and therefore more expensive
than open cavity molding. It is also sometimes desirable to
incorporate fabric into a portion of the top surface of the product
to provide, for example a carpeted section of a floor mat.
SUMMARY OF THE INVENTION
[0005] In one general aspect, the present invention features a
molding process for producing a molded product using a mold having
a lower plate and an upper plate. The molding process includes
steps of filling a first cavity of the lower plate with a molding
material of a first color, placing the upper plate on top of the
lower plate such that a convex portion of the upper plate extends
into the first cavity of the lower plate and contacts the molding
material in the lower plate, and curing the molding material.
[0006] The convex portion of the upper plate can have a plurality
of convex sections and a plurality of concave sections, and the
convex portion of the upper plate can be placed in the material
such that the convex sections contact the material and force the
material to flow into the concave sections of the upper plate. The
step of curing can occur before or after the step of placing. The
method can further include a step of filling a second cavity in the
lower plate with a liquid molding material of a second color. The
step of filling the second cavity can be performed before the step
of filling the first cavity. The method can include a step of
adding carpet material to the molded product. The method can also
include a step of clamping the upper plate to the lower plate.
[0007] Another general aspect of the present invention is directed
to an apparatus for producing a molded product using a material.
The apparatus includes a bottom plate having an upper mating
surface. The upper mating surface has a cavity to receive the
material. The cavity has bottom surface containing a plurality of
concave areas to form contoured features in a first surface of the
molded product. The apparatus can further include a top plate
having a top surface and a bottom mating surface. The bottom mating
surface can be constructed and arranged to mate with the upper
mating surface of the bottom plate. The bottom mating surface can
have a convex section arranged to extend into the cavity to contact
liquid material in the cavity. A bottom surface of the convex
section of the top plate can have a plurality of convex sections to
contact the liquid material in the cavity to form features in a
second surface of the molded product. The top plate can have a
plurality of holes extending from the bottom surface of the convex
section to the top surface of the top plate. The holes and the
convex sections of the top plate can be constructed and arranged
such that material in the cavity is forced into the holes by the
convex sections. At least one of the convex sections on the top
plate can be in the shape of a pyramid having four base edges
forming a polygon, the polygon having four corner points, and one
of the holes can be located at each corner point of the pyramid.
The top surface of the top plate can have a concave section that
captures material forced through the holes by the convex
sections.
[0008] Another general aspect of the present invention is directed
to an apparatus for producing a molded floor mat. The molded floor
mat has an upper surface and a lower surface. The apparatus
includes means for forming concave and convex features on the upper
surface of the floor mat and means for forming convex features on
the lower surface of the floor mat.
[0009] The means for forming concave and convex features on the
upper surface of the floor mat can include means for molding a
first part of the upper surface of the floor mat using a first
color of material and means for molding a second part of the upper
surface of the floor mat using a second color of material. The
apparatus can further include means for adding carpeting to the
upper surface of the floor mat.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] For a better understanding of the present invention,
reference is made to the drawings which are incorporated herein by
reference and in which:
[0011] FIG. 1 is a cross-sectional side view of a mold in
accordance with one embodiment of the present invention;
[0012] FIG. 2 shows area A of the mold of FIG. 1 in greater
detail;
[0013] FIG. 3 is a top view of an automotive floor mat produced
using the mold shown in FIG. 1;
[0014] FIG. 4 is a bottom view of the automotive floor mat of FIG.
3;
[0015] FIG. 5 is a cross-sectional side view taken along line 5-5
of the automotive floor mat of FIG. 3;
[0016] FIG. 6 is a top view of a bottom plate used in the mold
shown in FIG. 1;
[0017] FIG. 7 is a cross sectional side view taken along line 7-7
of the bottom plate shown in FIG. 6;
[0018] FIG. 8 is a bottom view of a top plate used in the mold
shown in FIG. 1;
[0019] FIG. 9 shows an area B of the top plate of FIG. 8 in greater
detail;
[0020] FIG. 10 shows a cross-sectional side view taken along line
10-10 of the top plate of FIG. 8;
[0021] FIG. 11 shows an area C of the top plate of FIG. 10 in
greater detail;
[0022] FIG. 12 is a flow chart of a method for producing molded
products in accordance with one embodiment of the present
invention;
[0023] FIG. 13 is a top view of an automotive floor mat having
carpet sections produced using a method of the present
invention;
[0024] FIG. 14 is a bottom view of the automotive floor mat of FIG.
13;
[0025] FIG. 15 is a cross-sectional side view taken along line
15-15 of the automotive floor mat of FIG. 13;
[0026] FIG. 16 is a top view of a bottom plate used to produce the
automotive floor mat shown in FIG. 13;
[0027] FIG. 17 is a cross-sectional side view of the bottom plate
of FIG. 16 taken along line 17-17;
[0028] FIG. 18 is a top view of a top plate in accordance with one
embodiment of the present invention having a hole through which
material can be injected;
[0029] FIG. 19 is a top view of a plug used with the top plate
shown in FIG. 18;
[0030] FIG. 20 is a cross-sectional side view of the plug of FIG.
19 taken along line 20-20;
[0031] FIG. 21 is a cross-sectional side view of the top plate of
FIG. 18 taken along line 21-21;
[0032] FIG. 22 is a cross-sectional side view of a mold in
accordance with one embodiment of the present invention having
clamping assemblies for clamping the top plate to the bottom
plate;
[0033] FIG. 23 is a side view if a plunger used in the clamping
assemblies of FIG. 22;
[0034] FIG. 24 is a side view of a top insert of the clamping
assemblies of FIG. 22;
[0035] FIG. 25 is a bottom view of the top insert of FIG. 24;
[0036] FIG. 26 is a side view of a bottom insert of the clamping
assemblies of FIG. 22; and
[0037] FIG. 27 is a side view of one of the clamping assemblies of
FIG. 22.
DETAILED DESCRIPTION
[0038] Embodiments of the present invention are described below
with reference to automobile floor mats. As understood by those
skilled in the art, the processes and apparatuses described below
may be used for manufacturing molded products other than floor mats
using a number of different materials.
[0039] FIG. 1 is a cross-sectional side view of an open cavity mold
10 used with embodiments of the present invention. FIG. 2 shows a
portion A of the open cavity mold 10 in greater detail. The open
cavity mold 10 includes a bottom plate 12 and a top plate 14. The
bottom plate 12 includes a concave section 16, and the top plate 14
includes a convex section 18 that extends into the concave section
16 of the bottom plate. In the embodiment shown in FIG. 1, the mold
10 is designed for producing automobile floor mats having an
overall shape defined by the perimeter of the concave section 16.
FIGS. 3-5 show an automobile floor mat 110 produced using the mold
10.
[0040] FIG. 6 shows a top view of the bottom plate 12 of the open
cavity mold 10, and FIG. 7 shows a cross-sectional side view of the
plate 12 taken along line 7-7 of FIG. 6. Around the base of the
cavity 12 are three concave rings 20, 22 and 24 that define three
convex ridges 120, 122 and 124 in the floor mat 110. As discussed
below, in embodiments of the present invention, each of the rings
120, 122 and 124 may be made from a different color of material. On
the bottom surface of the concave section 16 of the bottom plate
12, are a rear section 31, a heel section 32 and a front section 33
that respectively correspond to rear section 131, heel section 132
and front section 133 of the floor mat 110. Contained within the
rear section 31 and the front section 33 of the bottom plate are a
number of octagon shaped convex sections 26 and square convex
section 28 that form respectively concave sections 126 and 128 in
the floor mat 110. Disposed between each of the convex sections 26
are concave wells 30 that form ridges 130 in the floor mat 110.
Section 32 of bottom plate 12 has valleys 34 and ridges 36 that
respectively form raised ribs 134 and channels 136 in the floor mat
110.
[0041] The top plate 14 will now be described in greater detail
with reference to FIGS. 8-11. The convex section of the top plate
18 is designed to fit within the concave section 16 of the bottom
plate 12. The convex section has a lower surface 38 having a number
of contoured features contained therein for forming corresponding
contoured features in the floor mat 110. The lower surface 38 has
pyramid-shaped convex sections 40 that are designed to extend into
material in the concave section of the bottom plate when the top
plate is placed into the bottom plate as described below in further
detail. The pyramid-shaped convex sections 40 cause concave
sections 140 to be formed in the floor mat 110. At the bottom
corners of each of the pyramid-shaped convex sections are air holes
42 that extend through the top plate 14 from the bottom surface 38
of the convex section 18 to the top surface 19 of the convex
section. As described below, each of the air holes allows air to
exit the area between the top plate and the bottom plate as the top
plate is lowered into the bottom plate. In addition, the air holes
42 are designed to be filled with material to create nubs 142 on
the bottom surface of the floor mat 110.
[0042] The top plate 14 has an upper concave section 44 (see FIG.
1) on the top surface of the top plate opposite the convex section
18. The upper concave section forms a well for containing any
excess material that flows through the air slots 42 when the top
plate is placed into the bottom plate.
[0043] A method 200 in accordance with one embodiment of the
present invention for producing the floor mat 110 using the mold 10
will now be described with reference to FIG. 12. In a first step
202, the concave section 16 of the bottom plate 12 is filled with a
predetermined quantity of liquid rubber or plastic material. In one
embodiment, the material used is polyvinyl chloride. However in
other embodiments, other materials such as silicone can also be
used. During the first step, the top plate 14 is separated from the
bottom plate. Next, in step 204, the top plate is lowered into the
bottom plate so that the convex section 18 contacts the material in
the concave section 16. The pyramid-shaped convex sections 40 on
the bottom surface of the top plate contact the material as the top
plate is lowered, and any air trapped between the top plate and the
bottom plate is evenly forced out of the air holes 42. As the top
plate is lowered, the convex sections 40 force material to flow
into the air holes 42.
[0044] In embodiments of the invention, the quantity of material
used for filling the lower plate is selected so that material
completely fills all of the air holes 42. If excess material is
used, the excess material flows into the upper concave section 44.
After the top plate has been lowered into the bottom plate, then in
step 206, the mold 10 is placed into an oven to cure the material
in the mold. The temperature of the oven and the curing time used
depend on the material selected and the type of product being made.
In some embodiments, the top plate is clamped to the bottom plate
during the curing process to ensure that the top plate does not
move with respect to the bottom plate when the material is cured.
After the curing time, the mold 10 is removed from the oven, and in
step 208, the top plate is removed from the bottom plate. Next, in
step 210, the product is removed from the lower plate.
[0045] It is sometimes desirable to add a second color to a molded
product. In typical prior art processes, a second color is added by
painting the molded product after curing. In embodiments of the
present invention, a material having a second color can be added by
filling one or more of the rings 20, 22 and 24 with a material
having the second color prior to step 202 of the process 200. If
the material used for the second color (or other additional colors)
is less viscous than the material used for the first color, then
the first color may be poured directly on top of the second color
in the mold. If the material used for the second color is not more
viscous than that used for the first color, then in one embodiment,
the second color is cured in the oven prior to adding the first
color. The top plate may be placed on top of the bottom plate when
the second color is cured.
[0046] As understood by one skilled in the art, products having
more than two colors can be produced using three or more
different-colored materials, and the use of different-colored
materials is not limited to the outer rings, but different-colored
materials may be used in other areas of the bottom plate as
well.
[0047] In embodiments of the present invention, the top plate and
the bottom plate are made from aluminum, and can be manufactured
relatively inexpensively and quickly using well-known machining
techniques. In prior art injection molding techniques, the molds
are typically made from steel and are considerably more expensive
and require more time to manufacture than the top plate and the
bottom plate of embodiments of the present invention.
[0048] In embodiments of the molding process described above, the
top plate is added to the bottom plate prior to curing the
material. In other embodiments, the top plate may be placed into
the bottom plate either after the material is cured or after the
material is partially cured. In these embodiments, it may be
desirable to use clamps or a press to bring the plates together and
force the convex section of the top plate into the material in the
bottom plate.
[0049] The molding process described above provides several
advantages and overcomes problems associated with prior art open
cavity molding processes. The use of the convex sections 40 and air
holes 42 allows air to evenly escape to prevent the creation of
undesirable air pockets in the final product and also allows
features such as nubs 142 to be formed on the bottom surface of a
product. In typical prior art open cavity molding processes,
features are formed on either the top surface or bottom surface of
a product, but not on both surfaces as in embodiments of the
present invention.
[0050] In the embodiments described above, pyramid-shaped convex
sections 40 are used to evenly force air from between the plates
and to create the nubs 142. In other embodiments, convex sections
having other shapes, such as hemispherical, can be used in place of
the pyramid-shaped convex sections.
[0051] It is sometimes desirable to include carpeted sections in
floor mats and other molded products. In another embodiment of the
present invention, a method and apparatus is provided for producing
floor mats having carpeted sections. One embodiment of a carpeted
floor mat 410 produced using methods of the present invention is
shown in FIGS. 13-15. The carpeted floor mat 410 is similar to
floor mat 110 except that sections 131 and 133 of floor mat 110
have been replaced by carpeted sections 431 and 433 in floor mat
410. The method for producing the carpeted floor mat 410 in
accordance with the present invention is similar to the method 200
described above with reference to FIG. 12 with a few
exceptions.
[0052] The bottom plate 12 used with method 200 is replaced with
bottom plate 312 shown in FIGS. 16 and 17 to produce the carpeted
floor mat 410. Bottom plate 312 is similar to bottom plate 12 and
has sections 331, 332 and 333 corresponding to sections 31, 32 and
33 of bottom plate 12. Bottom plate 312 differs from bottom plate
12 in that sections 331 and 333 do not contain wells and ridges as
in sections 31 and 33. Sections 331 and 333 are convex sections
that create wells in the floor mat 410 that contain carpeted
sections 431 and 433.
[0053] Using bottom plate 312 and top plate 14, the carpeted floor
mat can be produced using method 200 with an additional step. After
the floor mat is removed from the mold in step 210, pieces of
carpet, sized to fit within wells created by sections 331 and 333
of the bottom plate, are adhered to the bottom surface of the
wells. The pieces of carpet may be adhered to the bottom surface of
the wells using an adhesive or double sided tape. Alternatively,
the pieces of carpet may be sewn or riveted into the product. The
pieces of carpet used to create the carpeted sections may be
obtained from one of several carpet manufacturers depending on the
style carpeting that is desired.
[0054] In embodiments of the present invention, a second color of
material can be added to the carpeted floor mat 410 using the same
method described above for floor mat 110. The second color of
material can be chosen to match the color of the carpet sections
used in the floor mat 410. In one embodiment, an emblem, or some
other feature, may be made from the second color, and the emblem
may be positioned on the upper surface of the floor mat such that
it extends through a hole in the carpeted section.
[0055] As described above, when adding a second material having a
second color to a product, in some embodiments of the present
invention, it may be desirable to cure the second material prior to
adding the first material having the first color. In these
embodiments, it may be desirable to cure the second material with
the top plate in place over the bottom plate. In one embodiment of
the present invention, which will now be described with reference
to FIGS. 18-21, a top plate 514 of an open cavity mold includes a
removable plug 515 to allow filling the mold with a first color of
material after the second color has been cured without removing the
top plate from the bottom plate. The top plate 514 is substantially
identical to the top plate 14 described above, except that the top
plate 514 includes a hole 517 for receiving the plug 515. The same
reference numbers are used to identify similar features of top
plates 14 and 514. Top plate 514 is designed to mate with bottom
plate 12 in a manner similar to top plate 14.
[0056] A process in accordance with one embodiment of the present
invention for using the top plate 514 in conjunction with the
bottom plate 12 to manufacture molded products using a first
material of a first color and a second material of a second color
will now be described. With the top plate 514 removed from the
bottom plate 12, the second material is poured into one or more
cavities in the top surface of the bottom plate. The top plate 514
is then placed on top of the bottom plate 12 and the combination of
the top plate and the bottom plate is placed in an oven to cure the
second material in the mold. After the second material has fully
cured, or in some embodiments has partially cured, the combination
of the top plate and the bottom plate is removed from the oven. The
plug 515 is then removed from the top plate 514, and the first
material is injected into the hole 517. In some embodiments, to
force the material into each of the holes 42, the material is
injected into hole 517 using a pressurized container having an
outlet adapter designed to mate with the top plate at the hole
517.
[0057] After the first material has been injected, the plug 515 is
inserted back into the hole 517. The combination of the top plate
and the bottom plate is then placed back into the oven to cure the
first material. After curing, the product in the mold can be
removed from the mold in the same manner as described above, and if
desired, carpet material can be added to the product.
[0058] As understood by one skilled in the art, in embodiments of
the present invention that utilize the top plate 514, more than two
colors may be incorporated into products by filling additional
cavities in the bottom plate with materials having additional
colors.
[0059] As discussed above, in some embodiments of the present
invention, it may be desirable to clamp the bottom plate to the top
plate prior to curing the material. In one embodiment of the
present invention, which will now be described with reference to
FIGS. 22-27, clamping assemblies are used to clamp the top plate 14
to the bottom plate 12. FIG. 22 shows a cross-sectional side view
of the open cavity mold 10 with two clamping assemblies 600 and 602
incorporated into the mold. In FIG. 22, the top plate 14 of the
mold 10 is split to show a first one of the clamping assemblies 600
in a disengaged position and to show a second one of the clamping
assemblies 602 in an engaged position. The clamping assembly 600 is
described below and shown in further detail in FIGS. 23-27, it
being understood that clamping assembly 602 is substantially
identical to clamping assembly 600. In embodiments of the present
invention, the number of clamping assemblies used in open cavity
molds may be more or less than two depending primarily on the size
of the mold.
[0060] The clamping assembly 600 includes a top insert 610, a
bottom insert 612, and a plunger 614. The top insert 610 is mounted
in a hole in the top plate 14, and the bottom insert 612 is mounted
in a hole in the bottom plate 12. The holes in the top and bottom
plates for the inserts are in alignment, when the top and bottom
plates are aligned. The plunger 614 is disposed in the top insert
and is movable between a disengaged position shown in solid lines
in FIG. 27 and an engaged position shown in dashed lines in FIG.
27. In one embodiment, the top insert, bottom insert and plunger
are made from steel, however in other embodiments, different
materials could be used.
[0061] The top insert 614 has four arcuate pliable tabs 620 that
extend from a cylindrical section 628. Each of the tabs 620 has a
tapered end section 630. The top insert includes a cylindrical
hollow section 632. In addition, a substantially cylindrical hollow
section 634 is formed by the four tabs 620.
[0062] The plunger 614 includes a knob 638, a cylindrical shaft 640
and a disc-shaped end section 642. The shaft 640 has an outer
diameter that is slightly less than the diameter of the cylindrical
section 628 of the top insert. The end section 642 has an outer
diameter that is greater than the diameter of the cylindrical
section 628, and slightly less than the diameter of the hollow
section 634.
[0063] The bottom insert 612 is cylindrical shaped and includes a
hollow inner chamber 644. The inner chamber 644 has an upper
surface 646 that slopes inwardly from top to bottom, a middle
surface 648 that slopes outwardly from top to bottom and a lower
vertical surface 650.
[0064] The clamping assembly 600 operates as follows. When the top
plate 12 is to be lowered onto the bottom plate 14, the knob 638 is
lifted to place the plunger in the raised position. Clamping
assembly 600 is shown with the plunger 614 in the raised position
in FIG. 22. As the top plate is lowered onto the bottom plate, the
tabs 620 of each top insert are lowered into the hollow chamber 644
of the corresponding bottom insert. When the tabs are lowered into
the hollow chamber, the tapered end section 630 of each tab
contacts the sloped upper surface 646 of the bottom insert causing
each of the tabs to move inward slightly. When the tabs are fully
inserted into the hollow chamber, such that the tapered end
sections are adjacent the vertical surface 650, the tabs return to
their original position. The plunger is then pushed downward to the
lower position. Clamping assembly 602 is shown with the plunger 614
in the lowered position in FIG. 22. With the plunger 614 in the
lowered position, the tabs are locked in place in the hollow
chamber. The plunger prevents the tabs from bending inwardly as is
necessary to move the tabs past the sloped upper surface 646.
[0065] When the top plate is to be removed from the bottom plate
after curing of the material, the knobs of each of the clamping
assemblies are lifted to the upper position. With the knobs lifted,
the tabs can be removed from the hollow chamber to separate the top
plate from the bottom plate. In one embodiment of the present
invention, the knobs are designed to mate with automated handling
equipment allowing the knobs to be moved between the upper position
and the lower position using the automated handling equipment. In
addition, the automated handling equipment can be used to lower the
top plate onto the bottom plate and to lift the top plate from the
bottom plate using the knobs.
[0066] In embodiments of the present invention described above, the
material used in molding processes has been described as liquid
material. As understood by those skilled in the art, the material
used need not be in liquid form, but may be in paste form or some
other form having sufficient viscosity to fill all cavities in the
top and bottom plates.
[0067] Having thus described at least one illustrative embodiment
of the invention, various alterations, modifications and
improvements will readily occur to those skilled in the art. Such
alterations, modifications and improvements are intended to be
within the scope and spirit of the invention. Accordingly, the
foregoing description is by way of example only and is not intended
as limiting. The invention's limit is defined only in the following
claims and the equivalents thereto.
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