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Publication numberUS3885008 A
Publication typeGrant
Publication dateMay 20, 1975
Filing dateAug 11, 1972
Priority dateNov 26, 1969
Publication numberUS 3885008 A, US 3885008A, US-A-3885008, US3885008 A, US3885008A
InventorsMartin Robert E
Original AssigneeMartin Robert E
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Method for producing prefabricated wall section with molded panels
US 3885008 A
Abstract
A prefabricated wall or roof section includes a frame with a molded panel bonded thereto, for installation as a unit with like units to form a building wall structure. The molded panel has a simulated masonry face; and the wall section includes integral insulation material applied to the back face of the panel within the frame. In the fabrication of the wall sections, a mold is formed from a plurality of perimetrically precision finished modular sections defining the base and confined within a frame or chase. The panel is formed from a homogeneous mixture of a high percentage of a comminuted sand-like material with a liquid containing appropriate bonding and chemical ingredients, which is applied within the mold and leveled with the mold frame. The wall section frame is immediately placed over the mixture, a layer of fiberglass reinforce plastic is applied to the mixture surface and to the adjacent frame surfaces for sealing and bonding of the mixture and frame. The assembly is then cured at a suitable temperature. After curing and cooling, an insulation coating is applied to the back surface of the panel within the wall section frame.
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Description  (OCR text may contain errors)

United States Patent 91 [111 3,885,008

Martin May 20, 1975 METHOD FOR PRODUCING PREFABRICATED WALL SECTION WITH MOLDED PANELS [76] Inventor: Robert E. Martin, Route No. 3, Box

188A, Gainesville, Tex. 76249 [22] Filed: Aug. 11, 1972 [21] Appl. No.: 279,871

Related US. Application Data [63] Continuation-in-part of Ser. No. 880,088, Nov. 26,

1969, abandoned.

[52] US. Cl. 264/45.3; 52/309; 52/314; 52/624; 156/245; 161/44; 264/255; 264/263; 264/46.4 [51] Int. Cl 329d 27/00; E040 2/02 [58] Field of Search 156/245; 52/314, 309, 624; 264/45, 255, 263

[56] References Cited UNITED STATES PATENTS 2,718,829 9/1955 Seymour et al. 52/309 3,131,514 5/1964 Siek 52/309 3,177,279 4/1965 Bilodeau 52/314 3,258,889 7/1966 Butcher 52/309 3,302,362 2/1967 Lang 264/45 3,328,231 6/1967 Sergovic 52/309 3,344,011 9/1967 Goozner 52/624 3,546,832 12/1970 Smith 52/309 3,640,796 2/1972 Cotelle 52/309 X Primary ExaminerH. S. Cockeram Attorney, Agent, or FirmPeter J. Murphy; Cecil L. Wood [57] ABSTRACT A prefabricated wall or roof section includes a frame with a molded panel bonded thereto, for installation as a unit with like units to form a building wall structure. The molded panel has a simulated masonry face; and the wall section includes integral insulation material applied to the back face of the panel within the frame. In the fabrication of the wall sections, a mold is formed from a plurality of perimetrically precision finished modular sections defining the base and confined within a frame or chase. The panel is formed from a homogeneous mixture of a high percentage of a comminuted sand-like material with a liquid containing appropriate bonding and chemical ingredients, which is applied within the mold and leveled with the mold frame. The wall section frame is immediately placed over the mixture, a layer of fiberglass reinforce plastic is applied to the mixture surface and to the adjacent frame surfaces for sealing and bonding of the mixture and frame. The assembly is then cured at a suitable temperature. After curing and cooling, an insulation coating is applied to the back surface of the panel within the wall section frame.

8 Claims, 22 Drawing Figures Pi-JENTEUMYZOWS 3,885,008 I sum 10F 4 INVENTOR.

Robert E. Martin ATTORNEY SHEET 3 BF 4 Fig.i

' INVENTOR.

Fig. 12

Robert E. Martin Fig.|O

ATTORNEY METHOD FOR PRODUCING PREFABRICATED WALL SECTION WITH MOLDED PANELS REFERENCE TO RELATED APPLICATION This is a continuation-in-part of application Ser. No. 880,088, filed Nov. 26, 1969 now abandoned.

BACKGROUND OF THE INVENTION Structural panels have been fabricated in a variety of forms and by different methods for both wood and metal framing to be installed as wall units. Such panels are usually fabricated with preformed sheets or slabs secured to some type of frame to be arranged in place to form a wall structure to which adequate insulating materials must be applied, and in general, such panels are not readily adaptable to low cost residential housing.

Where it is desirable to provide a variety of simulated masonry or plaster finished to the exposed surfaces, and afford a durable and attractive structure, most existing concepts of wall section panels for wood frame structures lack simple and economical securing means in erection.

SUMMARY OF THE INVENTION This invention relates to the fabrication of wall section panels primarily for wood frame structures.

A prime object of the invention resides in the provision of a wall section having a frame to which is bonded a molded panel formed of earthen materials such as sand, dolomite, perlite, and the like, and having a simulated masonry or plaster exterior finish and having an insulation backing; whereby a conventional type hollow load bearing outside or partition wall can be economically erected and without the necessity for the installation of suitable insulation or finish for the exposed surface.

Another object of the invention is that of providing a wall panel of reinforced plastic materials capable of withstanding inclement weather conditions, resisting such destructive factors as expansion and contraction due to extreme variations in temperature, and which is capable of being produced rapidly and economically in such form as to minimize the time and expense of installation and applying a suitable finish to the exposed surface.

Still another object of the invention is that of providing a method for fabricating the wall section, including the molded panel and the application thereof to the frame, whereby to afford an integrated unit having means for securing it to like units in a wall structure by persons of ordinary skill.

While the foregoing objects are paramount, other and lesser objects will become apparent as the description proceeds when considered with the appended drawings.

DRAWINGS FIG. 1 is a perspective exploded view showing a typical mold having removable sections of predetermined dimensions, and having a simulated masonry pattern, one of which is shown in elevated position for the purpose of illustration.

FIG. 2 is a fragmentary perspective illustration of one of the mold sections.

FIG. 3 is another perspective view of the mold in which a panel is in the process of being formed, a portion being broken away to show the mold surface.

FIG. 4 is a fragmentary sectional view, on line 4-4 of FIG. 3, showing a portion of the mold carriage and one of its castors, and showing the outer surface coating applied to the mold face.

FIG. 5 is a perspective view of a wall section frame applied to the initial application of surface material on 0 the mold, and before the backing material and insulation is applied thereto.

FIG. 6 is a fragmentary sectional view, on line 6-6 of FIG. 5, showing the panel surface material on the mold and showing the frame as applied thereto.

FIG. 7 is another perspective view of the mold assembly showing the section frame thereon and showing the applied reinforced backing for the surface material and fragmentarily showing some insulation in one corner of the frame.

FIG. 8 is a fragmentary view, on line 8-8 of FIG. 7, showing a corner of the frame to which the panel surface material and the reinforced backing material is applied thereto.

FIG. 9 is another fragmentary view, on line 99 of FIG. 7, similar to FIG. 8 in which the insulation is fragmentarily shown in section.

FIG. 10 is a front elevational view of a wall panel embodying the invention, having a simulated masonry pattern.

FIG. 11 is an edge elevational view of the section shown in FIG. 10.

FIG. 12 is a rear elevational view of a typical wall section to which the insulation has been applied.

FIG. 13 is a front elevational view of a wall section having a window opening therein.

FIG. 14 is a rear elevational view of the wall section shown in FIG. 13 having the insulation applied thereto.

FIG. 15 is a front elevational view of a typical column or corner section embodying the invention.

FIGS. 16 and 17 are transverse sectional views on lines 1616 or 17-17 of FIG. 15 showing the column or corner section as applied to the erected wall sections shown fragmentarily in broken lines. 1

FIGS. 18 and 19 are front and rear elevational views,

respectively, of a wall section having a door opening DESCRIPTION OF THE PREFERRED EMBODIMENT Broadly, a wall section according to the invention consists of a flat panel 10 which has been formed from a mixture in a suitable mold, the mixture consisting of comminuted earthen materials such as sand, liquids, and suitable bonding materials. A frame 12 of elongated structural members is laid over the panel 10, either prior to the setting of the plastic mixture or after it has cured, and is maintained in contact with the panel and bonded thereto to produce an integrated wall section of frame and panel. Insulation material may be applied to the back face of the panel mixture between the frame members during the fabrication of the wall sec tion.

Referring now to the structure of the wall section in greater detail and to its method of fabrication, a matrix or mold 1 1 is preferably composed of a plurality of planar rectangular segments 14 of metal, or other suitable material, and machined about their edges 15 to insure a precision joint with adjacent segments whereby to eliminate any defacing of the molded surface of the panel 10 by the appearance of mold marks. As seen in FIG. 2, one face of the segments 14 may be provided with a pattern of ribs or ridges to simulate, in the finished panel, the mortar joints of a brick wall for example. It will be apparent that these segments could be provided with ribs in another pattern to simulate a different type of surface.

The segments 14 of the mold are arranged within a frame which may comprise metal side and end members 16 and 17 joined at the corners by brackets 18 and bolts 19, as best seen in FIGS. 1, 3 and 4. Alternatively, the mold frame members may be of wood retained by a suitable tape if desired. The mold 11 may desirably be placed on a dolly 20 having a planar floor 21 supported on a frame 22, and having a plurality of casters 23.

The composition for the panel mixture, of which the panel 10 is cast in the above described mold, includes a solids component and a liquid component. The solids component is a desired quantity of finely comminuted earthen material which is crystalline in form and insoluble. Preferred forms of the solids component are common sand (usually rounded grains of quartz), dolomite which is a calcium magnesium carbonate, and perlite which is volcanic glassy rock. Other materials which may be used as the solids component are silica, ground quartz, and slack which is a derivative of burned coal cinders.

Broadly the liquid component consists of the following ingredients in indicated proportions by volume: (l) thermosetting resin functioning as a binder for the comminuted solids component, about 60%; (2) a resin thinner, about 25%; (3) a flow enhancing ingredient for producing a smooth flow of the resin, about 9%; and (4) curing agents including a promoter and an accelerator catalyst for producing an exothermic reaction for curing the panel mixture. It has also been found that a small amount of alcohol improves the workability of the mixture.

The resin selected for use in the liquid component may be a polyester resin, a vinylester resin, or an epoxy resin. Suitable polyester resins may be an isophthalic polyester resin or an orthophthalic polyester resin. An orthophthalic polyester resin is suitable, and practical from the standpoint of cost; and this type of resin is manufactured commercially by several companies, one such resin being identified as Marco 121-81 manufactured by the W. R. Grace Chemical Company. Also suitable is an isophthalic polyester resin, such as Polylite 33-41 1 manufactured by Reichold Chemical Company of Houston, Tex.

The resin thinner is preferably styrene which functions to reduce the viscosity of the resin in the liquid component, and has the further effect of increasing the flexibility and reducing the brittleness of the finished panel so that the finished wall section will be better 4 able to withstand deformation due to structural shifting.

The flow enhancing ingredient is preferably glycerine which functions as a form of lubricant to produce smooth flow of the resin and of the mixture of resin and solids component, and also functions to hold the resin and solids component together in a homogeneous mixture. Silicone may also be used as this flow enhancing ingredient.

The alcohol in the liquid component is preferably ethyl alcohol and functions to reduce the viscosity of the liquid component and improve the workability of the mixture.

The curing agents preferably consist of cobalt, functioning as a promoter, and methyl ethyl ketone peroxide (MEKP), functioning as an accelerator catalyst, which together create an exothermic or heat reaction for producing a cure condition in the mixture. MEKP is a well known compound used as a catalyst, and is marketed under the trade name Lupersol DDM by Argus Chemical Corporation, a subsidiary of Witco Chemical 850 Martin Ave., Richmond, California. Another combination of curing agents which may be used include benzoyl peroxide (BPO) [C H CO 0 functioning as a promoter, and dimethylaniline (DMA) C H N, which functions as an accelerator catalyst.

An example of one preferred form of the liquid component consists of the following ingredients, the proportions of each ingredient being indicated in approximate percentage by volume:

Polyester Resin 60% Styrene 25% Glycerine 9% Ethyl Alcohol 3% Cobalt 1.5% Methyl Ethyl Ketone Peroxide l.5% 100.0%

The polyester resin in the above example may be either the orthophthalic polyester resin or the isophthalic polyester resin identified herein.

The liquid component may be prepared in any desired volume and added to the dry ingredients in quantities necessary to produce the required wetness, depending upon the type and character of the materials used. The wet mix should be substantially fluid to avoid air pockets and bubbles in the finished panel. Satisfactory results can be attained by using a mix consisting of approximately to 82% of solids and 30 to 18% of liquids by weight. Color pigments may be added, as required, as well as an ultra violet modifier to eliminate the fading of the coloring materials.

The frame elements 16 and 17 have a depth dimension suitable to the thickness desired for the molded panel 10, as best seen in FIG. 3. After the mixture, of which the panel 10 is formed, is deposited in the mold 1'1, the frame structure 12 is applied thereto with the marginal outline of the frame 12 being accurately aligned with the marginal edges of the molded panel 10, as best seen in FIGS. 5 and 6 so that when the sections 13 are arranged in a wall structure, as shown in FIG. 20, the joints between the panels 10 are substantially imperceptible and can be readily treated to shut out moisture and eliminate any otherwise visible signs of a juncture between the panels 10.

The mixture is applied to the mold l1 and, by use of a screed, is smoothed to the level of the mold frame elements l6 and 17. After the finishing of the panel mixture within the mold, the frame 12 is applied to the mixture and positioned as indicated in FIGS. 5 and 6 in a manner that the peripheral edges of the frame 12 coincide with the peripheral edges of the panel mix as defined by the mold frame. Prior to the placing of the frame 12 however, it may be desirable to apply a resin putty to the surface of the mixture at low points thereof to assure sealing and bonding of the frame to the panel mixture when it is placed. This putty seal also serves to prevent seepage of the resin of the sealing and bonding coating to be applied immediately following. The resin putty may be made from the same polyester resin used for the liquid component. The frame 12 is maintained in contact with the plastic mixture through the stage of final curing.

The frame 12 may be formed of common dimension lumber, the end members 24 and the intermediate members 25 being conventional two by fours while the side members 26 are preferably conventional one by fours, the lesser thickness of the latter, when joined to a companion member of an adjacent section 13, will present a combined dimension equal to the thickness of a conventional two by four. The members comprising the longitudinal portions of the frame 12 are spaced according to conventional practice, and all of the frame elements are joined by nails, or other suitable device.

Following the placing of the frame 12, a coating or layer 31 of fiberglass reinforced plastic (FRP) is applied to the surface of the plastic mixture between the members of the frame 12 and along the adjacent surfaces of the frame members 24, 25 and 26, as best seen in FIGS. 7 and 8. As illustrated in these figures, the coating 31 of fiberglass reinforced plastic may consist of an open woven mesh of fiberglass 31a impregnated with a polyester resin. The fiberglass reinforced plastic layer may be applied, however, by any of well known techniques. One technique is to build a laminated structure of layers of a fiberglass mesh and coatings of polyester resin. Another technique is to apply a coating sion to the panel surface and to the adjacent perpendicular surfaces of the frame member.

The section 13 is then cured by the application of heat at approximately 180F. for about 10 minutes; and after being allowed to cool to about 125F., a coating of insulation material, such as polyurethane foam, is sprayed on the inner surface of the FRP coating 31 and allowed to set and assume a hardened foam-like consistency. The section 13 is removed at this stage from the mold 11.

In preparing the mold 11 for casting the panel 10 it is thoroughly cleansed of all foreign substances and a mold release compound is applied thereto and allowed to dry. For best results the mold 11 is preheated at this stage to approximately 140F. by any suitable means.

It is desirable that the sections 13 be of uniform dimensions, including those having window and door openings 27 and 28, respectively, as shown in FIGS. 13,

unit 29, which is angular in transverse section, is applied to a comer juncture of the sections 13, as shown in FIG. 16, and a unit 30, channel-shaped in transverse section, as shown in FIG. 17, for application to a wall joint. The side frame members 26 of the unit 30 are wider than those of the sections 13 to extend into the wall therebetween, in the manner shown in FIG. 17.

In FIGS. 21 and 22 is illustrated a typical device for joining the sections 13 in a wall structure, as shown in FIG. 20, comprising a pin 33 which may be of plastic, or other suitable material, having a head portion 34 and provided with a slot 35 through which a wedge 36 is inserted to secure the pin 33, as shown in FIG. 21, for joining the side frame elements 26. The sections 13 may be secured to a foundation 37 by anchor bolts 38, as indicated in FIG. 20.

The invention may be modified in structure and the method by which it is produced, by persons skilled in the art without departing from the spirit thereof or the scope of the appended claims.

What is claimed is:

1. A method for manufacturing a prefabricated build- 7 ing wall section including a thin wall panel defining a simulated masonry surface and a support frame integrally attached to one surface thereof including the steps providing a shallow mold having a substantially planar bottom wall, defining the mold surface for forming the exposed finish surface of a molded wall panel, and having side walls of uniform height to define the edges of the molded wall panel; mixing a liquid component'including, by volume, about of a thermosetting resin, about 25% resin thinner, about 9% flow enhancer, and a curing agent; mixing thoroughly about 18 to 30% by weight of said liquid components with about to 82% of a solids component consisting of a comminuted, crystalline, insoluble earthen material, to produce a homogeneous panel mixture;

filling said shallow mold with said panel mixture and leveling said mixture with the mold side walls;

placing a unitary, open panel supporting frame contiguous to the surface of said panel mixture exposed by said mold, while said mixture remains in said mold, in position to be bonded to said mixture;

applying a coating of fiberglass reinforced plastic to the exposed surface of said panel mixture and to the adjacent transverse surfaces of the wall frame members, to effect a bond between said panel and frame;

effecting the cure of said panel mixture and the bonding of said frame thereto;

and removing the integral assembly of cured panel and frame from said mold.

2. A method as set forth in claim 1 wherein said thermosetting resin is a polyester resin;

and wherein said resin thinner is styrene.

3. A method as set forth in claim 1 wherein said solids component is a material selected from a group consisting of sand, dolomite, perlite, silica, ground quartz and slack.

4. A method as set forth in claim 1 including the step of applying, after curing, a coating of polyurethane foam to the panel surface between the members of said frame.

5. A method as set forth in claim 1 about three-eighths inch; and wherein said frame is formed from framing members having a nominal 4 inch width in a direction perpendicular to the plane of the panel.

8. A method as set forth in claim 1 including providing a textured bottom wall for said mold for producing a correspondingly textured exposed finish surface of the molded panel.

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Classifications
U.S. Classification264/45.3, 156/245, 52/802.1, 264/46.4, 52/314, 264/263, 264/255, 52/745.19, 52/309.14
International ClassificationE04C2/24, E04C2/38, E04C2/10
Cooperative ClassificationE04C2/24, E04C2/386
European ClassificationE04C2/38D, E04C2/24