US 3398494 A
Description (OCR text may contain errors)
Aug. 27, 1968 E. H. LARSON WALL JOINT Original Filed Oct. 15, 1965 INVENTOR. ELTON H. LARSON AJ'TORNEYS United States Patent 3,398,494 WALL JOINT Elton H. Larson, 5105 Weeks, P.0. Box 10082, San Diego, Calif. 92110 Continuation of application Ser. No. 496,643, Oct. 15, 1965. This application Jan. 3, 1967, Ser. No. 617,739 9 Claims, (Cl. 52-371) ABSTRACT OF THE DISCLOSURE Preformed joint for two wall sections of a room, which wall sections are formed of plaster or stucco. The joint is inthe form of a unit including two coextensive screeds, one being attachable to one of the wall sections and the other being attachable to the other wall section. A coextensive strip is formed of impervious and inherently expansibleand contractible material which is interposed between flat sections of the aforementioned screeds, and is permanently bonded throughout both sides thereof with the fiat sections of the screeds.
The present application is a continuation of my application Ser. No. 496,643, filed Oct. 15, 1965, now 'abandoned, which application is a continuation-in-part of my application Ser. No. 218,383, filed Aug. 21, 1962, now abandoned.
Walls formed of plaster or stucco contract due to curing thereof, and also after curing, expand and contract due to changes in temperature. Such contractions and expansions cause cracking at the joints between two wall sections, with the result that patching must be done from time to time. Prior attempts have been made to overcome this need for patching, but such attempts were unsuccessful. One attempt now being used by the industry is as shown in the patent to Clark, No. 3,015,194, granted Jan. 2, 1962 on an application filed in June 1955. In actual practice, the plaster breaks away from the pleats 20 and 21, shown in that patent, while the plaster is curing. Furthermore, the resilient fold is formed of metal which, due to expansion and contraction, crystallizes and breaks. Moreover, it must be painted and when the paint is subjected to expansion or contraction, it cracks and falls away from the pleats. This pleat 10 is exposed to deteriorating atmosphere effecting corrosion thereof.
In practicing the present invention, I employ a strip of polysulfide material or a material having a polyvinyl base or a polyvinyl chloride, the sides of which are bonded, i.e., welded respectively, with the screeds.
Other features and the advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawing wherein preferred embodiments of the invention are illustrated.
In the drawing:
FIG. 1 is a fragmentary, cross-sectional view of one form of the invention, showing the cross section of a fiat wall which may be a vertical wall or a ceiling;
FIG. 2 is a top plan view of the wall shown in FIG. 1;
FIG. 3 is a fragmentary, cross-sectional view of the corner of joined exterior walls; and
FIG. 4 is a fragmentary, cross-sectional view of the corner of interior walls.
Referring more in detail to the drawing and particularly to FIG. 1 wherein there is shown fragments of a wall including two wall sections 22 and 24; these wall sections are preferably formed of plaster or stucco. The sections 22 and 24 are aligned. The metal laths are shown at 26 and 28 for the sections 22 and 24, respectively.
The joint comprises two screeds 30 and 32 in the form of elongated strips which are at least coextensive with the wall sections. In the embodiment shown in FIG. 1, the
3,398,494 Patented Aug. 27, 1968 screed 30 includes a relatively fiat section 34, and a section 36 which latter is disposed at right angles to the section 34. Like sections 38 and 40 comprise the strip 32. The sections 34 and 38 of the strips 30 and 32 are disposed parallelly of the wall sections 22 and 24 and the sections 36 and 40 confront one another. The screed or strip sections 34, 36, 38 and 40 are provided with a plurality of holes 42 through which the cementitious material extends and when hardened, provide a mechanical joint between the wall sections 22 and 24 and the screeds. The extruded cementicious material which extends through the openings 42 is shown at 44. The screeds are also provided with angularly disposed strips 46 forming anchors which extend into the cementicious material.
An impervious and inherently expansible and contractible finishing and joining strip 50, which may have any desired color, is interposed between the confronting sections 36 and 40. The opposite sides of strip 50 are bonded, i.e. Welded, to the confronting faces of sections 36 and 40. The material forming strip 50, in one form, is polysulfide such as that manufactured and sold by Chemical Corporation, 780 N. Clinton Ave., Trenton 7, New Jersey, under the trade name of Thiokol. It may also be formed of material having a polychloride base or it may be a silicone sealant. In the embodiment shown in FIG. 3, the wall sections 22 and 24 are at right angles with respect to one another, and, in this embodiment, the sections 36 and 40 are disposed at a angle with respect to the respective sections 34 and 38.
In the embodiment shown in FIG. 4, the sections 36 and 40 of the screeds are formed at an acute angle of 45, respectively, with the sections 34 and 38.
Thus, in FIG. 3 the contractible and expansible strip 50, which may be colored as desired, forms the finishing material for the corner of an outside wall while in FIG. 4, the strip 50 forms the finishing material for the inside corner of the two walls.
The screeds 30 and 32 may be formed of galvanized metal or zinc and are preferably formed by extruding a thermosetting polyvinyl chloride and thereafter the sealing strip is welded, i.e., bonded, to the confronting surfaces of the sections 36 and 40 of the screeds. The unit or assembly thus formed is sold in that form to the contractors. Thus, this unit is ready to install on a construction project at a minimum, construction cost compared to the very expensive system of installing two juxtaposed screeds and thereafter, calking the sealing material between the confronting surfaces of the screeds. The screeds and the strip 50 are herein shown at approximately full size.
It is well known that expansion and contraction take place in wall structures after construction. An expansion of approximately one hundred percent is more than ample for the material of strip 50 to take care of all expansions and contractions between sections 22 and 24. It has been found that a polyvinyl chloride base expansible and contractible material and silicone have the capacity of expanding more than one hundred percent, while it has been determined that polysulfide is capable of expanding as much as five hundred percent.
From the foregoing, it is readily apparent that by virtue of the present invention, a simplified joint has been provided which is inexpensive to manufacture as a unit and completely eliminates the necessity of calking at the construction project. Thus, the cost of joining two sections of wall has been materially reduced and provides for expediency in construction.
The strip 50 being bonded to the screeds 30 and 32 and being expandable, as aforementioned, cracks do not occur when the plaster cures, and, being compressible, the wall sections 22 and 24, carrying the screeds 30 and 32,
3 can move toward one another when the wall sections expand. Too, the entire unit is formed of materials which cannot corrode. Furthermore, the material forming the strips 50 can be colored prior to being bonded to the screeds, and therefore, since the strips are inherently expansible and contractible, they remain colored, as distinguished from painted metal pleats which paint, when subjected to expansion or contraction, cracks and falls away from the metal pleats.
While the forms of embodiment herein shown and described constitute preferred forms, it is to be understood that other forms may be adopted falling within the scope of the claims that follow.
. 1. An improved joint for two walls of a room, which walls are formed of material as for example, walls formed of plaster or stucco, which improvement comprises:
(A) a unit consisting only of:
( 1) a pair of elongated screeds, adapted for attachment, one to one of the walls and one to the other of the walls, each of said screeds including:
(a) an elongated, relatively flat section having holes for receiving Wet stucco;
(b) a second section disposed at an angle with respect to the flat section and having holes for receiving wet stucco, said second mentioned sections of the screeds having faces confronting one another and spaced from one another;
(2) and an impervious and inherently expansible and contractible finishing and joining strip interposed between said second mentioned sections and permanently bonded throughout both sides thereof to both confronting faces of the second mentioned sections of the screeds.
2. An improved joint as defined in claim 1, characterized in that the expansible and contractible strip is polysulfide.
3. An improved joint as defined inln ized in that the expansible and.,contractibleastriphas3a 4 polychloride base.
4. An improved joint as defined in claim 1, characterized in that the expansible and contractible strip is a silicone sealant. 4
5. An improved joint as defined in claim 1, characterized in that the screeds are formed-of mate'rial having a polychloride base. a b
6. An improved joint as definedfi n clainigj'characterized in that the screeds arl formed of mati'ial having a polychloride base.
7. An improved joint as defined in claim 3, characterized in that the screeds are formed of material having a polychloride base.
8. An improved joint as defined in claim 4; characterized in that the screeds are'formed of materia'fhavin'ga polychloride base. 1
9. An improved joint as defined in claim'5, character ized in that the screeds are formedofmaterial havirfg a polychloride base.
References Cited FRANK L. ABBOTT, Primary Examiner. JAMES L. RIDGILL, IR., Assistant Examiner.