CA2099547A1 - Method and apparatus for making building products - Google Patents

Abstract

Abstract of the Disclosure A decorative molded article simulating an object of construction used in a house or similar building, such as door or window, is made from a plastic sheet with one surface having a printed pattern which corresponds to a pattern on the simulated object and wherein the surface of the plastic sheet is deformed to correspond to the surface of the simulated object where the printed pattern and deformations are interrelated to closely resemble surface characteristics of the simulated object such as color, grain and shading. The decorative molded article is formed by a method in which the pattern of the simulated object is successively printed onto the plastic sheet by print screens which have been artistically and/or photographically developed with the pattern. The decorative molded article is formed in an apparatus which has fixed upper and lower platens spaced from one another and a movable mold platen which is moved in and out of the space between the two fixed platens. The upper fixed platen has a heat bank and an inflatable seal around the perimeter of the heat bank in order to form a seal to allow a vacuum to be applied underneath the plastic sheet, and air pressure to be applied over the sheet.

Description

2099~7 ~03 M~T~OD AND APPARATUS FOR MAKING BUILDING PRO WCTS

This invention is directed to a decorative molded article which simulates an object of construction, such as a door or window in a building, and to an apparatus and a method of making such an article.

Backqround of the Invention Various methods and devices are known for making a mold into which an article to be formed is cast. One such known method is disclosed in U.S. Patent No. 3,703,572 which contemplates making a pattern of the article to be cast from ; 10 any desired material and drilling a plurality of holes through the pattern. A thin thermoplastic sheet is then placed over the pattern and heated to render it pliant. The sheet is then subject to a vacuum through the holes in the pattern so that the sheet deforms and complies with the configuration of the pattern. The pattern together with the sheet now form the mold and are placed in a box. Molding material is then poured over the pattern in the box and is allowed to set. The hardened material forms a backing for the thin sheet. The sheet and the backing are then removed from the pattern and is then placed in a box or case where the desired molding material is then poured into the mold. The articles to be cast may be made of plaster, epoxy resin, silicon rubber, or foam.

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2099~47 Another method is disclosed in U.S. Pat. No. 3,773,879 in which an article is placed on a lower frame. A rubber sheet followed by a plastic sheet are placed over the article. An upper frame is then placed over the assembly. A foamable mat~rial is then poured into the assembly to deform the rubber sheet and plastic sheet to the contour of the article. ~fter hardening, the foamable material is removed from the frame and is drilled with small vent holes. The lower frame with the article attached is then placed over the hard foam material leaving a small gap. Mold material is then injected into the gap and allowed to cure. The mold is then ready for use.
A method of making a decorative pl~te is disclosed in U.S. Pat. No. 4,213,926. A transfer sheet with a pattern is laid face up into a frame. A forming mixture is then poured into the frame and is allowed to harden. The hardened material is removed from the frame and the transfer sheet then removed from the hard material. The result is a decorative plate for a building.
There has not been provided an apparatus and a method for molding thin articles wherein the article itself is a thin sheet which has been molded and configured to simulate a building product, such as a door or window. Similarly, prior methods and devices do not contemplate a high production process for making such building products.

20995~7 Summary of the Invention It is an object of this invention to provide a decorative molded article ~rom a thin sheet of material which has been previously printed with a pattern taken from the object to be simulated, and which has been molded to simulate an object of construction such as a wood door or a leaded glass window.
The molded article has a uniform thickness and is lightweight to be easily shipped and handled. The molded article is easily cut and is flexible to conform to irregularities in the surface to which it is mounted. The simulated wood door has a formed contoured surface which corresponds to the door to be simulated, and, in addition has a surface having a realistic wood grain-like appearance. The simulated door panel allows the user to reface interior doors instead of replacing the entire door which would incur great expense. The prefinished simulated wood door panel may be stained, painted and finished to enhance the printed wood grain surface, is easy to install requiring no special tools and little or no skill.
It is another object of this invention to provide yet another thin panel which has been molded, shaped and configured to resemble a leaded glass window. The simulated window may be either single or double paned. The simulated window may be clear or may be colored to simulate stained glass. ~dditionally, the window panel may have the elegant appearance of beveled leaded glass having either a smooth or textured surface.
It is yet another object of the invention to provide an apparatus for making such molded articles having a reciprocable mold onto which the sheet from which the article '' , : ' , ' ' ' "`

20995~7 is to be formed is placed. The mold is shuttled to a position between two fixed platens where the thin sheet is heated, and, after a prescribed time, an inflatable gasket or seal inflates and seals off the cavity between the mold and the upper platen so that a vacuum may be applied underneath the sheet and air pressure applied on top of the sheet to mold the article.
Another object of the invention is to provide a method for making such molded articles which comprise the steps of making a master pattern from the object to be simulated, developing the mold and/or the thin plastic sheets with a pattern which corresponds with an object to be simulated, registering the developed thin plastic sheet onto the mold and molding the article.
Finally, it is an object of this invention to provide a decorative molded article simulating an object of construction, such as a door or window, made from a plastic sheet with a printed pattern on one surface which corresponds to a pattern on the simulated object. The sheet with the printed pattern is formed such that surface characteristics of the simulated 20 object, such as color, grain, shading and texture, are closely resembled.

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De~criptio~ of the Drawinqs FIG. 1 is a flow chart setting forth the steps of making a simulated wood door;
FIG, 2 is a perspective view of the decorative simulated wood door;
FIG. 3 is a sectional view taken along the line 3-3 in FIG. 2;
FIG. 4 is a fragmentary cross section of the mold face with h laminate surface thereon;
10FIG. 5 is a fragmentary cross sectional view of the molded article formed by the mold face of FIG. 4;
FIG. 6 is a front elevational view of the molding apparatus;

FIG. 7 is a cross sectional view taken along the line 157-7 in FIG. 6;

. FIG. 7a is a cross section of the inflatable rubber . seal and the vacuum clamp used in the apparatus shown in FIG~.
6 and 7;

: FIG. 8 i5 a flow chart showing the steps of making a simulated leaded glass window;

: FIG. 9 is a perspective view of the molded simulated leaded glass window;
FIG. 10 is a view through line 10-10 in FIG. 9;
FIG. 11 is a perspective view of another form of the molded simulated leaded glass window;
FIG. 12 is a view through line 12-12 in FIG. 11;
. ., .

~ , . ' , 2099~7 FIG. 13 is a cross sectional view of a frame with a porous core and epoxy laminate therein; and FIG. 14 is a view of the porous core and epoxy laminate with the frame removed.

2 ~ 7 D~tailed Description of the Drawinqs Referring to the drawings and particularly to FIG. 1 which is a flow chart of a method of making a simulated article such as a door, it can be seen that a master pattern is provided in step 1 from which the mold is made that reflects the specific contoured surfaces and wood grain characteristics of the door to be simulated~ The master pattern may be the actual door to be simulated. Alternatively, the master pattern may be made from the actual wood door. In the latter instance, for example, the master pattern is formed from a wood article having substantially the same dimension of the door to be simulated but having a blank or unformed surface. The specific contours of the door to be simulated, for example, raised panel sections 33 (FIG. 2), are then carved or otherwise formed onto the blank surface of the master pattern by means of hand burrs, routing tools, or the like to reproduce the surface of the door to be simulated. ~fter the master pattern is made a frame F is constructed around the periphery of the master pattern P from, for example, metal strips to form a trough (FIG. 13).
The formed surface of the master pattern P, as well as the inside and top of the frame F, are then coated with a wax or similar releasing agent. This may be done in a number of ways, such as, for example, by rubbing the wax onto the surfaces by hand or by applying it with a brush or a spray. An initial epoxy gel or similar material 36 is then applied to the master pattern P and frame surface in step 2 of FIG. 1 as seen in FIG.
13. The epoxy gel 36 is preferably applied with a brush, but may 2099~7 be sprayed on. The epoxy flows over the contoured surface of the master pattern picking up the surface characteristics thereof, including the wood grain features 38 (FIG. 4). The epoxy coating is then reinforced with a glass backing, such as glass cloth or a glass mat 36'. The initial epoxy coating and glass mat 36' comprise the epoxy coating which has a thickness of approximately one-eighth of an inch.
The trough is then filled with a mass of highly porous material 52 (FIG. 13) having strength and rigidity, yet is permeable to air. The porous mass 52 is composed of coarse material, for example, small aluminum particles mixed with a bonding agent, such as an epoxy resin. The porous mass 52 is then covered with a backing board B that may be in any form, such as an aluminum plate. The epoxy coating 36 and porous mass 52 lS are then allowed to cure. The frame and master pattern are then broken away or removed with the board B left in place resulting in an epoxy mold having a porous core 52 (FIG. 14).
The final step in preparing the mold for use consists of drilling a plurality of holes 40 (FIG. 4) over the entire surface of the laminated porous mass 52. The holes are drilled throuqh the epoxy mold into the porous core 52 which has been provided with means to connect to a vacuum source such as hollow tube 52a (-FIG. 7~ to assist in the molding process to be discussed below.
The epoxy mold 36 with a porous core 52 can be seen most clearly in FIG. 4, shown reversed to match FIG. 5, where the raised or textured surface at 38 corresponds to the wood ' , , ' :

20995~7 grain pattern formed from the article to be simulated and the concave portion 42 corresponds to raised panel sections on the simulated wood door.
A rubbing of the raised wood grain is made in step 3 (FIG. 1) from the mold onto a dimensionally stable sheet that is simply placed on top of the mold. The sheet can be of any dimensionally stable material, such as dimensionally stable polyethylene terpthalate sold by Dupont de Nemours under the trademark Mylar TM. The rubbing is generally only made on the flat face of the mold as seen at 41 in FIG. 4. The rubbing is made with any form of rubbing tool, such as a graphite stick or dark crayon. Where a rubbing cannot actually be made, for example, in a concave section 42 of the mold face as seen in FIG.

4, a rubbing is taken from another portion to blend the areas.
15The rubbing can also be achieved by another manner in which the deformations in the mold surface, such as at 42 in FIG. 4, are filled with original wood from which the mold was made or with a filler, such as a plastic filling compound.
The mold now has a flat face onto which the sheet is placed.
The edges of the sheet are sealed to the mold with tape, for ; example, and the mold with the attached sheet are subjected to a vacuum in a manner described below to cause the sheet to be pulled into firm engagement with the flat mold surface. This allows a higher definition rubbing to be made. The sheet now 2S has impressions of the wood grain formed from the rubbing.

Additional wood grains with light and dark tones are drawn, painted or otherwise artistically developed in step 4 : .

_g _ 2~99547 (FIG. 1) on separate sheets. There are now, for example, three separate sheets. ~ first sheet with wood grains rubbed therein, a second sheet having light wood tones and a third sheet having darker wood tones. If necessary, additional sheets may be developed to obtain the desired final wood appearance.
Print screens are then made in step 5 ~FIG. l) from each sheet in a known manner to perform a typical screen printing operation to transfer the wood characteristics onto a plastic product sheet which eventually becomes the molded article. For example, the image of each sheet is photographically developed onto a print screen in a manner in which the image is inked or otherwise transferred from the screen onto the product sheet.
After all screens have been printed with toner, midtones and dark grain represented by steps 6, 8, 10 with drying steps 7, 9, ll between each printing, the resulting product sheet now has the image of a wood door thereon. This process is a typical screen printing operation and the same steps are used for all of the sheets until the final image of the simulated article appears on the product sheet. For example, in FIG. l the product sheet is printed in step 6 from a screen made from the fir~t sheet to obtain the original wood hue with wood grain and is allowed in step 7 to dry. An intermediate wood tone is then printed in step 8 from a screen made from the second sheet onto the product sheet which is then allowed in step 9 to dry. Dark grains are then printed in step lO from a screen made from a third sheet on the product sheet. The product sheet with the light and dark tones and wood grain pattern thereon in step lO

209~7 is allowed in step 11 to dry and is then ready ~or the molding c~cle in step 12 in which the plastic sheet is registered in step 13 onto the mold such that the wood ~rain pattern printed thereon accurately coincides with the wood grain pattern and designs on the mold. The plastic sheet is then molded in step 1~
to form a simulated wood door and after the molding process described below has occurred, the simulated wood door panel is then removed in step 15 from the mold.
The resulting article is a thin sheet 32 as seen in FIG. 2 with a contoured surface or deformations corresponding to raised panel sections 33 and a printed and textured surface simulating wood grain. The surface of the decorative article closely resembles the surface characteristics of the simulated door with similar color, grain, shading and texture or other characteristics.
The thin sheet 32 may then be applied to a door giving a new appearance. The sheet 32 is trimmed to the dimensions of the door and secured thereto with glue or similar adhesive.
The sheet requires no further finishing but may be stained and further finished, if desired.
The process of forming a simulated leaded glass window is similar to that of forming a simulated wood door with the steps being set out in the flow chart of FIG. 8. A master pattern is provided in step 16 which may be the actual window to be simulated or constructed to duplicate the window. The master pattern is then prepared with a release agent as in the process for making a door. A frame is then built up around the sides of ~ ~ .

:. ' ': - , .. .

209~5~7 ~he master pattern to form a trough and the epoxy or similar material is applied thereto in step 17. The porous material is then poured into the trough and is backed with a backing board until the epoxy and the porous material have cured, at which time the frame and master pattern are removed. Holes are then drilled through the epoxy and into the porous core.
Print screens are then made in the aforementioned manner where lead lines are photographically developed onto the screen in step 18. Separate screens are then photographically developed in step 19 for each of the different colored glass sections if the stained glass window effect is desired. For example, one screen is made for all glass sections of the color red. ~nother is made for all blue glass sections and so on until all of the colored glass sections have been developed on a print screen. A clear plastic product sheet is then printed in the known manner with the lead lines in step 20 and is allowed to dry in step 21. Then, if desired, each color of glass sections is printed one color at a time in steps 22, 24 with a drying step 23, 25 between each color printing. The molding cycle 26 begins when the printed product sheet is registered in step 27 onto a mold. The product sheet is then molded in step 28, and thereafter demolded in step 29 in accordance with the invention as will be discussed below. If a clear glass effect is desired, only lead lines are printed onto the clear produce sheet. The result is a simulated leaded glass window with clear glass sections.

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It may also be desired to have both a clear and stained glass effect. In this instance, the colored sections are printed with the desired color, while the sections that are to remain clear are not printed with color.
The resulting simulated leaded glass window is seen in FIG. 9 at 72. In this embodiment, the glass sections 75 are smooth. In the embodiment of FIGS. ll and 12, the glass sections 75' are rough or textured. Raised printed portions 73 represent lead lines on the window to be simul~ted and may be used to form a decorative design corresponding to the simulated window.

Sur~aces 74 may be beveled so that the overall design with the raised printed lead lines and the printed colored glass sections or clear glass sections forming the decorative design simulate an elegant leaded glass window effect. The deformations in the simulated window closely resemble surface characteristics of the real window having raised lead lines, bevels and either a smooth or textured surface.
The simulated leaded glass window is adapted to be mounted within a wall opening by any means, such as a snap on finishing system (not shown) that may be stained to simulate rich oak moldings. The end result is a window having an elegant simulated leaded glass appearance and a maintenance free exterior.
The invention a~so contemplates a simuiàted leaded glass window used as a decorative add-on to an existing window.

The simulated window may be trimmed to the size of an existing window and assembled to the interior side of the window by any .
' 20995~7 means, such as a plastic snap-on clip assembly (not shown) as is known in the art. The decorative interior add-on may be easily removed for cleaning.
The apparatus for forming the molded articles are best seen in FIGS. 6 and 7. The apparatus consists of mold assembly 44 and platen assembly 48. The mold 52 is fastened onto a movable platen 45 on the mold assembly 44 and is pneumatically shuttled (by means not shown) or by hand in the direction of arrow A in and out of the space 50 between the fixed upper and lower platens 49, 51. A vacuum clamp 46 is hinged to the mold 52 and secures the printed plastic produce sheet 32 after it has been loaded onto the mold. The vacuum clamp 46 is an extruded aluminum frame 46a defining a plenum 46c (FIG. 7A) with openings 46b. Rubber seals 46d are provided along each side of the frame 46a to provide a vacuum seal for securing the plastic sheet 32. A vacuum is applied to the frame from a source ~not shown~ and thus to the plastic product sheet 32 through the plenum 46c and openings 46b to securely hold the plastic sheet 32 to the mold 52.
The platen assembly 48 comprises upper andlower fixed platens 49, 51 with a space 50 therebetween. The upper fixed `
platen has a heat bank 53 (FIG. 7) with individual electrical resistance-type heating elements 54 therein and an inflatable gasket or seal 55 which surrounds the heat bank at the lower edge thereof. The seal 55 is connected to the upper platen 49 by means, such as brackets 55a, 55b. The seal 55 has a hollow cylindrical portion 56 and an integral planar mounting portion ' ;,.~..................................... : .

2099~47 57. The mounting portLon 57 is clamped by the brackets 55a, 55b to the heat bank 53.
After the mold has traveled to a position between the two fix~d platens as seen in FIG~ 7, the heat bank 53 is turned on in order to heat the plastic product sheet 32 making it pliant or elastic so that it may be vacuum formed to comply with the configura~ion of the pattern on the mold which comprises the epoxy coating 36 and porous core 52. After a prescribed time period of heating, sufficient to heat the sheet to molding temperature, the seal 55 which extends around the perimeter of the heat bank 53 is inflated and seals off the cavity 56 between the mold and the top platen 49. At this time a vacuum is applied to the porous mold 52 and vacuum holes 40 in the laminate 36 (FIG~ 4) by a source through means 52a and the softened plastic product sheet 32 is drawn onto the mold by the differential pressure. ~fter the plastic product sheet 32 has been conformed onto the mold by the vacuum, the cavity 56 formed between the mold and the top platen 49 is pressurized with air through inlet 49a from a source (not shown), thus, increasing the force with which the plastic product sheet 32 is forced onto the mold and greatly increasing the detail of the part.
After the plastic product sheet 32 is formed, the seal 55 is deflated and retracts with a vacuum releasing the forming pressure in the cavity 56. The heat is turned off and the mold platen 45 moves out from between the fixed platens 49, 51. If desired, a fan 47 may be used to cool the plastic product sheet 32 while it is retained on the mold by the vacuum clamp 46.

2099~7 After the product sheet is cooled, the vacuum clamp is turned off and released so that the molded part can now be demolded and a new plastic product sheet loaded into the mold.
It is within the scope of this invention that another mold and movable platen may be added to the opposite end of the platen assembly 48 of FIG. 6 to function as a double ended shuttle machine. Thus, when one sheet is being heated and formed, another sheet is being unloaded and loaded. This will double the production capabilities of the machine.

Claims (10)

1.
A decorative molded article simulating an object of construction used in a house or similar building comprising, a plastic product sheet of generally uniform thickness having opposed surfaces;
one of said surfaces having a printed pattern thereon corresponding to a pattern on the simulated object;
said product sheet having deformations corresponding to a surface of the simulated object;
said printed pattern and said deformations being interrelated to closely resemble surface characteristics of the simulated object, and said product sheet having outside dimensions corresponding to the simulated object such that said product sheet has the appearance of the simulated object.

2.
A decorative molded article as in claim 1 wherein said product sheet is a thin panel simulating a wood door and the printed pattern on said one of said surfaces thereof is in the form of simulated wood grain, color and shading.

3.
A decorative molded article as in claim 1 wherein said product sheet is a thin panel simulating a leaded-glass window and said printed pattern on said one of said surfaces of the product sheet is in the form of simulated lead lines.

4.
A decorative molded article as in claim 3 wherein said product sheet is clear acrylic.

5.
A decorative molded article as in claim 3 wherein said printed pattern on one of said surfaces of the product sheet comprises a colored decorative pattern surrounded by said simulated lead lines simulating stained glass.

6.
A decorative molded article as in claim 3 wherein said deformations on said product sheet are in the form of simulated textured glass.

7.
A method of making a decorative molded article simulating an object of construction used in a house or similar building comprising the steps of providing a master pattern of the object to be simulated, applying an epoxy coating on a surface of the master pattern to pick up surface characteristics thereof, forming a mold with the epoxy coating thereon, making a rubbing from the mold onto a dimensionally stable plastic sheet, artistically forming additional wood grain and wood tones on separate sheets, forming print screens from each sheets, providing a plastic product sheet which eventually becomes the molded article, successively screen printing on one surface of said product sheet by using said print screens to form a pattern representing wood grain and wood tones corresponding to the wood grains and wood tones of the simulated article, registering the printed pattern on the product sheet with the pattern on the mold face, molding the product sheet to conform to the mold, and removing the product sheet from the mold.

8.
A method of making a simulated leaded glass window comprising the steps of providing a master pattern of the object to be simulated, applying an epoxy coating on a surface of the master pattern to pick up surface characteristics thereof, photographically developing lead lines onto a printing screen, providing a plastic sheet which eventually becomes the molded article, successively screen printing on one surface of said product sheet by using said screens to form a pattern representing a simulated leaded glass window, registering the printed pattern on the product sheet with the pattern on the mold face, molding the product sheet to conform to the mold, and removing the product sheet from the mold.

9.
The method as recited in claim 7 further comprising the steps of photographically developing different colored glass sections onto separate screens and printing the colored glass sections onto the plastic sheet.

10.
An apparatus for making decorative molded articles comprising a mold, means for clamping a sheet to be molded on said mold, an upper fixed platen and a lower fixed platen spaced therefrom, means for moving said mold into and out of the space between said upper and lower platens, heating means within said upper platen for heating an article to be molded, inflatable seal means on said upper platen for sealing the space between the mold and the upper platen, vacuum means on said lower platen to draw the article onto said mold, and air supply means on said upper platen to supply pressurized air to the space between the upper platen and said mold.