US2219806A - Hollow rib lath - Google Patents

Description

Oct. 29, 1940. e. A. BUTTRESS HOLLOW RIB LATH Filed Aug. 4, 1938 Patented Oct. 29, 1940 VUNITED STATES PATENT OFFICE to Buttress Board Company, Los Angelcs, Calif., a corporation of'California Application August 4,

Claims.

This invention relates to lath and more particularly pertains to hollow rib sheet lath of the character set forth in my copending application for United States Patent Ser. No. 137,960, filed 5 April '20, 1937, and also set forth in United States Patent No. 2,077,513, issued April 20, 1937; the

present invention more particularly pertaining to improvements in the metallic reinforcments of the hollow rib structure.

The primary object of the present invention is to provide a metallic reinforcement for the hollow ribs of the lath which is extremely light in weight and of such form and character as to facilitate driving of nails through the reinforced ribs and 18 whereby the resultant lath structure will be more easily handled and applied.

Another object is to provide a construction in a metallic reinforcement which while affording adequate strength will involve the use of a greatly decreased amount of metal over the construction heretofore employed.

A further object is to provide a metal reinforced construction in the hollow rib of a sheet lath such as will permit adjacent lath panels being mounted with their ends overlapped and overlapping end portions readily crushed and indented so that a body of plaster of adequate thickness may be applied over the overlapped end joint of the lath to obviate cracking of the plaster along said joint.

-With the foregoing objects in view, together with such other objects and advantages as may subsequently appear, the invention is carried into effect as illustrated by way of example in the accompanying drawing, in which:

Fig. 1 is a view in elevation of the hollow rib sheet lath showing it as applied;

Fig. 2 is a detail in section as seen on the line 2--2 of Fig. 1 in the direction indicated by the arrows;

Fig. 3 is a view in elevation of a fragmentary portion of a metallic reinforcing strip showing it as detached;

Fig. 4 is a detail in section taken on the line 4-4 of Fig. 1 as seen in the direction indicated by the arrows showing the manner of overlapping and crushing the ends of the sheet lath in forming the joint between adjacent panels thereof;

Fig. 5 is a detail in perspective of a fragmentary portion of the lath as seen from the back thereof with portions removed and depicting the metallic reinforcing strip in place.

Fig. 6 is an enlarged detail in section taken on the line 6-6 of Fig. 5.

Referring to the drawing more specifically, A

1938, Serial No. 223,060

indicates generally a corrugated facing sheet formed of flexible fibrous material such as paper, pulp board or the like, and is preferably of moisture'absorptive character throughout. The corrugations of the sheet A are of substantially 5 dove-tail cross section and are formed to provide relatively wide hollow ribs 1 and relatively narrow dove-tail channels 8 between adjacent of the ribs.

The corrugated sheet A is affixed to a backing 10 sheet B preferably formed of a flexible fibrous material such as paper and which is preferably treated to be fire-resistant and moisture proof; the sheet A being affixed to the backing sheet B by adhering the bottom walls of the channels 15 8 to the backing sheet by means of a suitable adhesive.

In carrying out the present invention the inner surfaces of the hollow ribs 1 are coated with a layer!) of plastic cementitious material which is 20 of moisture resistant character, such as asphaltum, that has been treated to render it fire resistant.

Partially imbedded in the layer 9 is a metallic reinforcing strip C which embodies a pair of 5 wires l0 apart so as to form-a series of trans- 1 versely triangular webs b as particularly shown in Figs. 3 and 5. Y

In order to avoid stretching of the webbing, transverse slits c are formed between the contiguous longitudinal webs b which slits permit spreading of the web b laterally of the strip to any desired distance within the length of the diagonal marginal portions of the web. In thus spreading the marginal wires H] to form the Webbing II the metal strips constituting the 5 webbing are bent to lie in angular relation to the plane of the reinforcing strip as particularly shown in Figs. 2 and 6, thus presenting the webbing substantially edge-wise to the outer walls of the rib I and thereby rendering the webbing quite resistant to bending inwardly under pressures imposed on the outer faces of the lath rib.

The marginal wires H] of the reinforcing strip C are spaced apart such distance as to snugly nest in the acute angle formed interiorally of the marginal portions of the ribs 1 such that the side walls :1 of the ribs and channels will aid in anchoring and holding the reinforcing strip C in position against the outer wall of the ribs. The margins of the wires II] are spaced from the backing sheet B so as to render the side walls :2 of the ribs and channels subject to being readily collapsed at the ends of the ribs on applying the sheet lath to a supporting structure, as will presently be described.

By forming the reinforcing strips C as herein set forth the open webbing b renders the strip quite foraminous such as to readily permit driving of nails through the ribs I.

In applying the sheet lath to its supporting structure, such as studding D, as shown in Fig. 1, panels of the lath of suitable dimensions are applied to the studding and secured thereto .by nails l2 which latter are driven through the ribs 1. In order to avoid a crack between the ends of adjacent lath panels, as is likely to occur where the sheet panels are abutted end to end, the end portions of .the adjacent panels are overlapped with the end portions of the ribs thereof in longitudinal alignment with each other. A nail 1-2 is then driven through each rib and the overlying end portions of theribsarepoundeddown so as to .collapse of the side walls 11 thereof as shown in Fig. 4, and whereby the overlapping end portions of the panels may be formedtoextend substantiallyfiush with or be indented relative to the plane of the front face of the assembled panels, so that when a body of plaster E is applied over the jointsuch plaster will have a thickness equal to if not 5 slightly exceeding the thickness of the plaster protruding in front of the faces of the ribs 1 intermediate the ends of the panels, thus obviating subsequent cracking of the plaster along the joints between ends of adjacent lath panels as sometimes occurs where lath panels are abutted at their ends.

The foraminous structure of the metal :reinforcing strip C permits the latter being crushed down at the overlapping joints at the ends'of the lath panels without placing the reinforcing strips under tension.

By expanding the metal of the reinforcing strip as herein set forth a considerable reduction in the amount of metal required to form the strip is effected over that required where the strip is formed of a ribbon-of metal of the width of the rib I, thus effecting an economy in metal and also decreasing the weight of the lath panel, and yet affording adequate strength for light construction purposes.

While I have shown and described a specific embodiment of my invention I do not limit myself to the exact details of construction set forth, and the invention embraces such changes, modifications and equivalents of the parts and their formation and arrangement as come within the purview of the appended claims.

I claim:

1. In a hollow ribbed sheet lath, embodying a corrugated facing sheet formed to provide hollow ribs and channels of dove-tailed cross section, a backing sheet, and a metallic reinforcing strip interiorally of said hollow strip, said strip embodying spaced marginal wires of angular cross section, an open webbing interconnecting said wires, and a cementitious material on the inner wall of said ribs in which the webbing of said reinforcing "strip is partially imbedded.

2. In a hollow ribbed lath, a backing sheet, a fibrous corrugated facing sheet formed with ribs and channels, said ribs being hollow, a layer of plastic material adhered to the inner face of the outer wall 'of said ribs and a foraminous metallic reinforcing strip at least partially imbedded in said plastic material. 3. In a hollow ribbed lath, a backing sheet, a fibrous corrugated facing sheet formed withribs and :channels of dove-tailed cross section, said ribs being hollow, a layer of plastic material adhered to the inner face of the outer wall of said ribs and a foraminous metallic reinforcing strip at least partially embedded in said plastic material, said strip having continuous marginal wires extending contiguous the side walls of said channel.

4. In a hollow ribbed lath, a backing sheet, a fibrous .corrugated facing sheet formed with ribs and channels of dove-tailed cross section, said ribs being hollow, a layer of plastic material adhered to the inner face of the outer wall of said ribs and .a foraminous metallic reinforcing strip at least partially imbedded in said plastic material, saidcstrip-having continuous marginal wires extending contiguous the side Walls of said channel, said reinforcing strip being formed of sheet metal with the wire margins thereof of angular cross section, and with a webbing interconnecting said wire margins the marginalportions of which extend in angular relation to the plane of the face-of the reinforcing strip.

5. Ina hollow ribbed lath, a corrugated facing sheet of flexible fibrous material the ribs and channels of which are of dove-tailed cross section, a backing sheet to which the facing sheet is afiixed, spaced metallic wires extending longitudinally of said ribs interiorally thereof and seating in the acute angle formed at the intersection of the side walls and the outer wall portion of the dove-tailed ribs, and plastic means holding said wires in place.

GEORGE A. BU'I'I'RESS.

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