`Tyler
`
`USOO6953545B1
`(10) Patent No.:
`US 6,953,545 B1
`(45) Date of Patent:
`Oct. 11, 2005
`
`(54) METHOD FOR PRODUCING CONTOURED
`VEHICLE FLOOR MATS HAVING
`INTEGRALLY FORMED NIBS
`
`1/1971 Price ............................. 18/10
`3,555,601. A
`4,828.898 A * 5/1989 Bailey ...
`... 428/88
`5,171,619 A * 12/1992 Reuben ..
`... 428/95
`5,554,333 A * 9/1996 Fujiki ........
`... 264/284
`
`(75) Inventor: Robert D. Tyler, Winfield, KS (US)
`
`6,020,044 A * 2/2000 Sugihara - - - - - - - - - - - - - - - - - - - - - - 428/85
`
`(73) Assignee: Winfield Consumer Products, Inc.,
`Winfield, KS (US)
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 0 days.
`
`(*) Notice:
`
`FOREIGN PATENT DOCUMENTS
`JP
`O1159234. A * 6/1989
`* cited by examiner
`Primary Examiner Edmund H. Lee
`(74) Attorney, Agent, or Firm-Shook Hardy & Bacon
`
`Sep. 30, 1999
`(22) Filed:
`(51) Int. Cl. ................................................ B29W 51/10
`(52) U.S. Cl. ................. 264/554; 264/1771; 264/210.1;
`264/334; 264/348
`(58) Field of Search ................................. 264/334,348,
`264/554, 177.17, 210.1
`s
`s
`
`(56)
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`2,623,242 A 12/1952 Grover ....................... 425/339
`2.915,427 A * 12/1959 Schriner et al. ............ 154/110
`
`A method of producing contoured vehicle floor mats having
`integrally formed nibs. The sheet is formed by a nib forming
`roll in an extrusion roll stack having a plurality of inden
`tions. The nibbed sheet is placed onto the thermoform mold
`with the nibs directed away from the mold. The sheet is
`heated to a plastic State and Stretched over the mold to form
`a contoured mat shaped to vehicle within a vehicle
`compartment, trunk or cargo area. The nibs on the underside
`of the mat contacts the floor covering and prevents the mats
`from Sliding on the interior Surface of the vehicle.
`
`18 Claims, 2 Drawing Sheets
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`EX1054
`Yita v. MacNeil
`IPR2020-01139
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`U.S. Patent
`U.S. Patent
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`Oct. 11, 2005
`Oct. 11, 2005
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`US 6,953,545 B1
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`METHOD FOR PRODUCING CONTOURED
`VEHICLE FLOOR MATS HAVING
`INTEGRALLY FORMED NIBS
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`CROSS-REFERENCE TO RELATED
`APPLICATIONS
`
`Not Applicable.
`
`STATEMENT REGARDING FEDERALLY
`SPONSORED RESEARCH OR DEVELOPMENT
`Not Applicable.
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`BACKGROUND OF THE INVENTION
`This invention relates generally to a method for manu
`facturing plastic floor mats for vehicles. More Specifically,
`the invention relates to a method for manufacturing plastic
`floor mats molded to correspond with the three dimensional
`profile of the interior of a vehicle floor and having a plurality
`of integrally molded nibs on the Surface of the mats to
`contact the vehicle's floor covering.
`Mats are often placed over the floor board of a vehicle to
`protect the floor covering. Particularly, mats are useful to
`prevent the carpet or other floor covering from becoming
`worn, Stained or otherwise damaged by the occupants of the
`vehicle or items stored within the vehicle.
`Protective vehicle mats come in a variety of shapes and
`sizes. One typical prior art mat is a mat constructed from a
`flat sheet made of fabric, rubber or plastic material. The mats
`are typically flexible and are laid across the floor board
`Surface of the vehicle. One drawback of these type of mats
`is that they tend to slide across the floor board due to the
`forces applied by the passengers of the vehicle or by the
`motion of the vehicle itself. One prior art solution to this
`problem is to apply protrusions Such as nibs to the Surface
`of the mats contacting the floor board. Typically, the nibs are
`formed as Small Spikes with pointed ends that grip the floor
`board Surface of the vehicle. The nibs are generally equally
`distributed acroSS the underlying Surface to provide a num
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`ber of individual contact areas. The main drawback of these
`flat mats is that they do not effectively cover the contoured
`surfaces of the floor board. Specifically, the flat mats are not
`effective for protecting the corners of the vehicle floor board
`or those areas having more complex Surface shapes. Further,
`even those flat floor mats having nibbed surfaces tend to
`move along the floor board Since the nibs are not in contact
`with the large, contoured area of the floor board and do not
`benefit from the lateral Support afforded contoured mats.
`Some prior art mats are produced to closely correspond to
`the shape of a vehicle floorboard and overcome the problems
`inherent with flat sheets. The complementary shape of the
`contoured mat mates with the vehicle floorboard to hold the
`mat into place. However, the prior art processes for produc
`ing these contoured mats have a number of Shortcomings.
`One prior art process is the use of thermoforming to produce
`a multi-dimensional, contoured mat. In this process, a poly
`mer sheet is placed over a Solid molding from defining the
`shape of the mat. The sheet is Softened by heating in an oven
`and is held to the form by either vacuum or air pressure
`forcing the Sheet against a female or male tool. However,
`while this prior art method has been effective for forming
`appropriately shaped mats at a relatively low cost, the prior
`art thermoforming processes do not disclose a method for
`forming integral nibs on the mat. In Some cases, manufac
`turers have attached a plate having a nibbed Surface to the
`bottom of the thermoformed mat as part of a Secondary
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`operation. Typically, the plate is Secured to the mat by a
`mechanical means or by one of a variety of adhesives.
`Besides requiring an additional Step, the mats formed in this
`manner typically only have nibs on the lower, flat portion of
`the mat Surface. The contoured portion of the mats, Such as
`the upwardly extending Sidewalls of typical floorboards are
`left Smooth and do not grip the floor covering of the vehicle.
`Also, in Some Situations, the fixed plate may either become
`loose or partially Separated from the contoured mat.
`Some prior art processes have produced integrally formed
`nibs on the underside of a contoured mat. One example of
`Such a proceSS is injection molding. In this method, molten
`material is injected into the cavity and cooled to form the
`final part. In another process, used primarily with rubber
`mats, the mat is compression molded within a closed mold
`placed under pressure. However, these processes are
`particularly, if not prohibitably, costly. Accordingly, a pro
`cess is needed that allows nibs to be integrally formed within
`a multi-dimensional, contoured mat without the costs asso
`ciated with these expensive prior art techniques.
`
`BRIEF SUMMARY OF THE INVENTION
`It is an object of the present invention to provide a method
`for producing contoured vehicle mats having integrally
`formed nibs that is significantly less costly than prior art
`methods.
`A further object of the present invention is to provide a
`method for manufacturing plastic Vehicle floor mats having
`integrally formed nibs using a thermoforming process.
`Another object of the invention is to provide a process for
`forming contoured floor mats having integrally formed nibs
`by using an extrusion process to form the nibs and a
`thermoforming process to provide the contour to the mats.
`According to the present invention, the foregoing and
`other objects are achieved by extruding a thermoplastic
`material through a roll Stack having a roll having a plurality
`of indentions for forming nibs. The heated material is
`pressed onto the Surface of the central roller by an adjacent
`roller so that material fills the indentions to form nibs on one
`side of the sheet. As the sheet is pulled from the central
`roller, the integrally formed nibs are released from the
`indentions. Next, the sheets are cooled and cut into blanks
`for forming the mats. The blanks are placed within a
`thermoforming station with the nibbed side of the blank
`directed away from the surface of the molding tool. The
`blank is heated to a plastic State and drawn toward the
`contoured tool by vacuum pressure. Thereafter, the blank is
`stretched over the tool to form the contoured shape desired
`for the particular vehicle. Thus, a contoured, plastic vehicle
`mat having integrally formed nibs on the underSide of the
`mat is produced using the thermoforming process.
`Additional objects, advantages and novel features of the
`invention will be set forth in part in the description which
`follows, and in part will become apparent to those skilled in
`the art upon examination of the following, or may be learned
`from practice of the invention. The objects and advantages
`of the invention may be realized and obtained by means of
`the instrumentalities and combinations particularly pointed
`out in the appended claims.
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`BRIEF DESCRIPTION OF THE SEVERAL
`VIEWS OF THE DRAWINGS
`A preferred embodiment of the present invention will be
`described below with reference to the attached drawing,
`wherein:
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`FIG. 1 is an elevational Schematic view of the vehicle mat
`production line according to the present invention;
`FIG. 2 is an enlarged, partial Side elevational view of the
`extruder of the present invention;
`FIG. 3 is an enlarged, fragmentary Side elevation view of
`the extruding rollers of the present invention;
`FIG. 4 is an enlarged view of the extrusion rollers within
`the captured region 4 of FIG. 3;
`FIG. 5 is a perspective view of the thermoforming mold
`ing tool of the present invention; and
`FIG. 6 is a perspective view of a vehicle floor mat made
`in accordance with the present invention.
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`DETAILED DESCRIPTION OF THE
`INVENTION
`Referring to FIG. 1, a vehicle mat production line gen
`erally designated by the numeral 10 is shown. Specifically,
`the production line is directed to a method for manufacturing
`plastic vehicle mats having a contoured, multi-dimensional
`shape. Nibs or Similar Structures are integrally formed on the
`underSide of the mats to prevent the mats from Slipping on
`the surface of the vehicle covered by the mats. The mats may
`be placed in the driver floorboard, the passenger floorboard,
`or the backseat floorboard. Furthermore, the mats may serve
`as cargo liners and be formed to fit the trunk of an automo
`bile or the Storage area of a van, truck, or Sport utility
`vehicle.
`The vehicle mat production line 10 includes an extruder
`12, a first conveyer 14, a Second conveyor 16, a run-out table
`18 and a thermoforming Station 20. Generally, the nibs are
`integrally formed in the mat material at the extruder 16 and
`the form fitting contour is molded at the thermoforming
`station 20.
`With additional reference to FIG. 2, the extruder 12
`includes a feed hopper 22, an extrusion barrel 24, a die 26
`and a roll stack 28. Generally, feed material in the form of
`pellets or granules is placed within feed hopper 22. The feed
`material is a combination of a linear low density polyeth
`ylene material and one of a group of thermoplastic elasto
`meric (T.P.E. or T.P.O.) materials. The linear low density
`polyethylene material enhances melt Strength in thermo
`forming process and increase wearability (or durability) of
`the floor liner. A linear low density polyethylene material
`sold by Phillips Petroleum under the name K203 is used. The
`thermoplastic material is one of a group of thermoplastic
`elastomers. Most preferably, the thermoplastic elastomerS is
`either a blend of polypropylene and EPDM rubber or a blend
`of polypropylene, EPDM rubber and EVA. For example, two
`particular blends of polypropylene and EPDM rubber are
`sold by the Advanced Elastomers Systems, Akron, Ohio,
`under the names VYRAM and SANTOPRENE. An example
`of an effective blend of polypropylene, EPDM rubber and
`EVA is Sold by the same company under the name
`VISTAFLEX. In the most preferred embodiment, the feed
`material is a blend constituting 60% of the K203 low density
`polyethylene and 40% of the VYRAM thermoplastic elas
`tomer. The examples of thermoplastic elastomers are
`representative, and various other thermoplastic elastomers
`having Similar melt Strength and other physical characteris
`tics may be advantageously used in the part forming process.
`Similar, blends having various ratios of low density poly
`ethylene and thermoplastic elastomer material may be used
`without departing from the Scope of the invention.
`The feed material slides downwardly from the feed hop
`per 22 and into the extrusion barrel 24. In the barrel, a screw
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`4
`(not shown) heats the material until the plastic reaches a
`homogenous fluid state. With the preferred material blend
`discuss above, the extrusion occurs at a temperature between
`395-420 degrees Fahrenheit and at a pressure between
`1800–2400 psi. With additional reference to FIG. 2, the
`Screw forces the material through a Screen pack 30 located
`at the end of the barrel. The screen pack 30 filters the plastic
`material and Supplies back pressure to the material remain
`ing in the extrusion barrel 24. Next, the plastic material is
`forced through a valve die adaptor 32 and finally through an
`orifice (not shown) in die 26. The shape of orifice of the die
`26 defines the croSS Sectional profile of the material exiting
`the barrel 18. Heretofore, the extrusion process discussed
`above is conventional in the art of plastic extrusion pro
`CCSSCS.
`With reference to FIG. 3, once the extruded material 34
`exits the die 26, it enters the roll stack 28 of the present
`invention. The roll stack 28 is comprised of lower roll 36, a
`central nib-forming roll 38 and an upper roll 40. The lower
`roll is generally Smooth (or is minimally textured) and
`rotates in a first rotated direction. As shown in FIG. 4, the
`nib-forming roll 38 has a plurality of indentions 42. Each
`indention 42 has a tapered Sidewall that define a Small
`cavity. The sidewalls meet to form a rounded or sharply
`pointed end at the bottom of the indentions. The indentions
`42 are preferably Spaced equally from one another to create
`an equal dispersion pattern of nibs in the sheet. However, the
`indentions may be formed in any of a variety of geometric
`configurations. For instance, in Some embodiments, it may
`be desirable to have a higher concentration of nibs along the
`periphery of the sheet to enhance gripping at the more
`contoured Surfaces of the vehicle Surface.
`To form the nibs, the extruded material 34 is pressed
`between the lower roll 36 and nib forming roll 38. The
`material 34 is pushed into the form of a mat sheet 46 due to
`the pressure between the rolls 36 and nib forming roll 38
`which rotates in a Second direction opposite from lower roll
`36. As the mat sheet 46 is formed, some of the thermoplastic
`material is forced into and fills the indentions 42 of nib
`forming roll 38. With still further reference to FIG. 4, as the
`mat sheet 46 rolls around nibbed roller 38, the nibs 44
`remain in the indentions 42 until the upper roll 40 pulls the
`mat sheet 46 from the nib forming roll. As the mat sheet 46
`is spooled onto upper roll 40, rotating in the direction
`opposite from nibbed roll 38, the nibs 44 are released from
`the indentions in the nib forming roll 38.
`Next, the mat sheet 46 is directed along the inclined first
`conveyor 14. The conveyor is driven by a conventional pull
`roll 48. At this stage in the production line 10, the mat sheet
`is Sheared along its edges by a Shear cutter 49 to define a mat
`sheet of constant width. Moreover, the sheet 46 cools as it
`proceeds down the first conveyor 14. Next, the mat sheet 46
`travels along the second conveyor 16. At the end of the
`generally horizontal Second conveyor 16, the sheet 46 is
`forced downwardly by a pneumatic hold down 50. The mat
`sheet 46 is sheared into mat blanks 52 at the shear table 54.
`At this point, the mat blanks 52 are removed from the run out
`table 18 of the first stage of the production line 10. As shown
`in FIG. 5, the mat blanks 52 may be sized to produce a single
`mat or may be of an appropriate size to be simultaneously
`molded into a number of mats.
`With reference now FIGS. 1 and 5, the thermoforming
`component of the vehicle mat production line 10 is shown.
`The thermoforming Station 20 generally includes a loading
`station 55, an oven 56 and a mold 58 located within the oven
`56. The blanks 52 are placed on the conventional loading
`station 54 and transported into the oven 56. In the novel
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`method of the present invention, the mat blank 52 is loaded
`on the loading station 54 so that Smooth (or slightly textured)
`side 60 is directed toward the mold 58 and the nibbed side
`62 is directed in the direction opposite the mold. Next, the
`mat blank 52 is placed directly over the mold 58. The mold
`58 is preferably a male tool contoured to shape the vehicle
`surface to be covered by the mat. The mold 58 has a
`block-like base 64, an upstanding form 66 on the upper
`surface of the base 64 and a flat peripheral ledge 68 between
`the outer edge on the form 66 and the edge of the base 64.
`In the preferred embodiment, the form 66 includes upwardly
`extending sidewalls 70 and a top 71. As would be
`understood, the form 66 may take any of a wide variety of
`complex shapes have a plurality of curved, flat and transi
`tional Surfaces typical of the interior floorboards of passen
`ger vehicles, and cargo areas of a variety of trucks, Vans and
`Sport utility vehicles.
`The mold 58 includes a plurality of vacuum apertures 72
`formed thereon. To form the mat blank 52 into the formed
`mat 73, the blank 52 is heated by the oven 56 and the
`negative vacuum pressure applied through vacuum apertures
`72 draws the blank toward the mold 58. While the preferred
`embodiment relies Solely on vacuum preSSure, the inventive
`technique also contemplates methods of utilizing differential
`pressure to force the blank into contact with the mold (i.e
`pressure or a combination of pressure and vacuum). The hot
`plastic blank 52 is pulled in contact and held against the
`surface of the mold 58. The plastic cools to form the mat 73
`shown in FIG. 6. Then, the mats 73 are removed from the
`mold. If necessary, the outer periphery of the mats may be
`trimmed to confirm the mat to the shape of the vehicle
`Surface to be covered.
`In the preferred embodiment, the mat 73 has a relatively
`flat base 74 and a number of upstanding sidewalls 76 shaped
`by the upstanding form 66 and against ledge 68. AS men
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`tioned before, this shape is merely illustrative of a typical
`driver or passenger Side floor board, and a number of
`differently shaped mats, Such as cargo liners, may be formed
`according to this inventive process.
`The process of the present invention is particular well
`Suited for producing vehicle mats. However, parts Suitable
`for different applications may be produced by thermoform
`ing nibbed sheets in accordance with the thermoforming
`process of the present invention. Furthermore, the use of
`thermoplastic blend, particularly the preferred blend, allows
`the nibs to be formed by an extrusion roller and produces a
`sheet ideally Suited for the thermoforming process of the
`present invention.
`The inventive method overcomes the problems of prior art
`thermoforming processes by placing the nibs into a sheet of
`material prior to thermoforming, and directing the nibs in the
`direction opposite the male tool. The inventive method of
`thermoforming contoured plastic Vehicle mats from sheets
`having integrally formed nibs is advantageous for a number
`of reasons. First, the only processes previously known for
`forming Such shapes involve complex tooling Such as cavity
`molds that greatly increase the price of the product to the
`consumer. The other processes for incorporating nibs onto a
`contoured mat involve mechanically or adhesively fastening
`a sheet of nibs to the underside of the mat. In addition to
`adding an extra Step in manufacturing and the problems
`asSociated there with, it was difficult to place nibs entirely
`across the lower Surface of the mat. In the method of this
`invention, not only are the nibs capable of being formed on
`all of the Surfaces of the mats, the nibs are directed in the
`direction Substantially perpendicular to the Surface and are
`extremely effective for gripping the interior Surfaces of the
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`vehicle. Furthermore, the process allows nibbed mats to be
`formed in a infinite variety of shapes at a relatively low cost.
`Further, mats may be formed to completely line and cover
`the vehicle floorboards and cargo areas while tightly grip
`ping those Surfaces with the dispersed pattern of nibs formed
`throughout the mat.
`While preferred embodiments and particular applications
`of this invention have been shown and described, it is
`apparent to those skilled in the art that many other modifi
`cations and applications of this invention are possible with
`out departing from the inventive concepts herein. It is
`understood that Substitutions may be made and equivalents
`employed herein without departing from the Scope of the
`invention as recited in the claims.
`What is claimed is:
`1. A method of producing a vehicle mat comprising the
`Steps of
`providing a sheet of thermoplastic material, Said sheet
`having a first and Second Side, Said Second Side having
`a plurality of nibs extending therefrom;
`placing Said sheet directly over a contoured molding tool
`having one or more Sidewalls that extend upwardly
`from a base and a top Surface, Said first Side directed
`toward Said Sidewall and top Surface of Said tool and
`Said Second Side directed away from Said tool;
`heating Said sheet; and
`drawing Said heated Sheet toward Said tool until Said sheet
`is Substantially shaped to the contour of Said Sidewall
`and Said top Surface of Said tool, wherein a portion of
`Said heated sheet shaped to the contour of Said Sidewall
`of Said tool has said Second side with a portion of the
`plurality of nibs extending therefrom arranged Such that
`said portion of the plurality of nibs extend in a different
`direction than another portion of the plurality of nibs
`extending from Said Second Side of another portion of
`Said heated sheet shaped to the contour of Said top
`Surface of Said tool.
`2. The method of claim 1, wherein said thermoplastic
`material is a thermoplastic elastomer.
`3. The method of claim 1, wherein said sheet is drawn
`toward said tool by differential pressure.
`4. The method of claim 1, wherein at least one vacuum
`aperture is formed in Said tool, and wherein Said sheet is
`drawn toward Said tool by applying vacuum pressure
`through Said vacuum aperture.
`5. The method of claim 1, wherein said sheet is blank for
`producing at least one mat.
`6. The method of claim 1, further comprising the steps of
`cooling Said sheet and removing Said sheet from Said tool.
`7. A method of producing a plastic Vehicle mat comprising
`the Steps of:
`extruding a sheet of thermoplastic material between a pair
`of rollers wherein one of said rollers has a plurality of
`indentions to form nibs on a first side of the sheet;
`placing Said sheet directly over a contoured male molding
`tool having one or more Sidewalls that extend upwardly
`from a base and a top Surface, Said first Side directed
`away from Said tool;
`heating Said sheet to a plastic State; and
`drawing Said heated Sheet toward Said tool until Said sheet
`is Substantially shaped to the contour of Said Sidewall
`and Said top Surface of Said tool, wherein a portion of
`Said heated sheet shaped to the contour of Said Sidewall
`of Said tool has said Second Side with a portion of the
`plurality of nibs extending therefrom arranged Such that
`said portion of the plurality of nibs extend in a different
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`direction than another portion of the plurality of nibs
`extending from Said Second Side of another portion of
`Said heated sheet shaped to the contour of Said top
`Surface of Said tool.
`8. The method of claim 7, wherein said thermoplastic
`material is a thermoplastic elastomer.
`9. The method of claim 8, wherein said thermoplastic
`elastomer is a blend of a linear low density polyethylene and
`thermoplastic elastomers.
`10. The method of claim 7, wherein said sheet is drawn
`toward Said tool by vacuum pressure.
`11. A method of producing a part comprising the Steps of:
`providing a sheet of thermoplastic material, Said sheet
`having a first and Second Side, Said Second Side having
`a plurality of nibs extending therefrom;
`placing Said sheet directly over a contoured molding tool
`having one or more Sidewalls that extend upwardly
`from a base and a top Surface, Said first Side directed
`toward Said Sidewall and top Surface of Said tool and
`Said Second Side directed away from Said tool;
`heating Said sheet; and
`drawing Said heated Sheet toward Said tool until Said sheet
`is Substantially shaped to the contour of Said Sidewall
`and Said top Surface of Said tool, wherein a portion of
`Said heated sheet shaped to the contour of Said Sidewall
`of Said tool has said Second Side with a portion of the
`plurality of nibs extending therefrom arranged Such that
`said portion of the plurality of nibs extend in a different
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`direction than another portion of the plurality of nibs
`extending from Said Second Side of another portion of
`Said heated sheet shaped to the contour of Said top
`Surface of Said tool.
`12. The method of claim 11, wherein said thermoplastic
`material is a thermoplastic elastomer.
`13. The method of claim 11, wherein said thermoplastic
`material is a blend of a linear low density polyethylene and
`a thermoplastic elastomer.
`14. The method of claim 11, wherein said sheet is drawn
`toward said tool by differential pressure.
`15. The method of claim 11, wherein said vacuum pres
`Sure is applied through Vacuum apertures in Said tool.
`16. The method of claim 11, further comprising the steps
`of cooling Said sheet and removing Said sheet from Said tool.
`17. The method of claim 1, wherein the steps of heating
`Said sheet and drawing Said heated sheet toward Said tool are
`performed within an oven.
`18. The method of claim 1, wherein said portion of said
`heated sheet shaped to the contour of Said Sidewall of Said
`tool has Said portion of the plurality of nibS eXtending from
`Said Second Side thereof in a direction Substantially perpen
`dicular thereto, and wherein Said another portion of Said
`heated sheet shaped to the contour of Said top Surface of Said
`tool has said another portion of the plurality of nibs extend
`ing from Said Second Side thereof in a direction Substantially
`perpendicular thereto.
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