Roofing-sheets of Fabric.
Year: 1889

page_text: Date of Application, 31st Dec., 1889-Accepted, 8th Mar., 1890
COMPLETE SPECIFICATION.
Roofing-sheets of Fabric.
I, HENRY WARD JOHNS, residing at the Dakota Apartment House, Corner of
Seventy-second Street and Eighth Avenue in the City of New York, State of New
York, United States of America, Manufacturer and Merchant, do hereby declare the
nature of my invention for ROOFING SHEETS OF FABRIC and in what manner the
same is to be performed, to be particularly described and ascertained in and by
the following statement :-
My invention relates to improvements in roofing fabrics so called. The fabrics
referred to are such as are patented to me in United States Letters Patent
No. 125,574, dated April 9th, 1872, and are composed generally speaking of an
inner layer of canvas, coated with pitch, tar, asphaltum, or like substance, and an
under sheet of manilla or other strong paper, and an upper sheet of felt or like
material, usually saturated with some waterproofing compound, the several sheets
being pressed firmly together and firmly attached to each other by passing them
between rollers.
In the manufacture of these prior roofing fabrics it has been found impossible to
bring the edges of the sheets evenly together owing to the deviation of the canvas
from a straight line, even if of the same width as the other sheets in places, and also
the different degrees of compactness with which different pieces of canvas are made,
and also different parts of the same piece which occasion differing degrees of
stretching and consequent contraction in width as the canvas passes through the
machine, it has therefore been necessary in order to secure substantially straight
edges to trim the edges of the compound sheet after manufacture, this involves
additional time and labor and a very considerable waste, moreover it necessitates the
cutting off of the selvage edge of the canvas, which is particularly desirable to retain,
owing to its strength and also because the nails used to attach the sheets to the
roof do not tear out therefrom as readily as from the trimmed edge of the
canvas. In the drawings the same reference letters indicate the same parts in all
the figures.
Figure 1, illustrates a perspective view of the principal parts of a machine used by
me in making my new roofing material.
Figure 2, illustrates a side view of the machine, the steam cylinder nearest the
observer having been removed and the remaining cylinder and sheets of material being
broken off the better to illustrate the apparatus, the felt sheet alone appears in this
figure.
Figures 3, 4, 5, 6, 7 and 8, illustrate vertical sections of pieces of roofing fabric as
made by me.
Figure 9, illustrates a side view of the machine similar to figure 2, but showing the
turning in of one edge of the canvas.
Figures 10 and 11 illustrates a form of inner sheet, which I employ instead of
the canvas when desiring to make less expensive goods; the construction of this
cheaper sheet I will hereinafter describe.
A is the frame of the machine which supports two hollow cylinders B, B', which if
desired may be heated in any suitable manner, preferably by steam injected through
the journals. They are adjustable towards and from each other by means of sliding
journal boxes C, C, and thumb screws D, D. E is a roll of canvas, F is a roll of
saturated felt, G is a roll of manilla or equivalent paper, they are all fed in between
the cylinders simultaneously, the canvas being preferably, but not necessarily, in the
center and the felt and paper on either side of it. The pitch, tar, asphaltum, or
equivalent adhesive and waterproofing material is supplied from any suitable source
upon these several fabrics as seen at H, H. It is prevented from escaping at the
ends by shields I, I, which press closely against the ends of the cylinders, they may
iD 077

page_text: be lined with any suitable material, such as rubber if necessary, to make the joint
tight. J, J, are hemmers similar to those used in connection with sewing machines,
they are used by me to turn over the edge of the canvas, the felt or the paper
composing the compound sheet as hereinafter set forth; they are detachably attached
to the shields I, I, or at any other suitable point. These shields serve as guides for
the several strips of material as they are fed to the machine.
The operation is as follows:-
All three sheets are fed to the machine as shown. The paper and the felt will
run evenly and will be properly superposed one upon the other, with their edges
evenly meeting each other, being guided by the shields I, I, and by properly adjusted
tension, but the edges of the canvas are ordinarily so irregular that they will not
run evenly to coincide with the edges of the other sheets, I therefore in order to
straighten the edges of the canvas employ the hemmers as shown in Figures 1, 2
and 9, which are so arranged as to turn over the latterally projecting uneven portions
of its edges prior to the compression by the cylinders, and I run the canvas of such
width that at no part will it be narrower than the width of the paper and felt, thus
the edges of all the sheets are adjusted exactly to each other and they are even,
uniform and straight. A compound sheet of this kind with the edges of the canvas
turned in is shown in figure 7. I show it turned in on one edge more than at the
other, thus illustrating the unevenness of the canvas. Where the edges of the
canvas happen to run straight and to coincide with the edges of the other sheets there
will be no turning thereof by the hemmers on either side; on the contrary at such
parts they will run straight through the hemmers, which then act as guides simply
for the several sheets or layers. In such cases the resulting compound sheet will be
as seen in Figure 3, the canvas having on it the selvage edge. It will sometimes
happen that one edge of the canvas will run straight and in coincidence with the
edges of the other sheets while the other edge of the canvas will project laterally and
will consequently be turned in by the hemmers. In such cases the resulting
compound sheet will be as shown in Figure 8, the turned in edge being at the left
and the unturned edge at the right. Sometimes I purposely make one or more of
the sheets or layers which are to compose the compound sheet wider than the
completed sheet is to be and then turn one or more edge of such wide sheet or sheets
back upon itself before they pass through the rollers, the folding over of such edge or
edges compresses a portion of the ceinenting compound away from the same, this
turning over of the edge or edges thickens the edge of the sheet and prevents the
cementing material from running out from between the several sheets when softened
or partially melted by excessively hot weather or by the use of the fabric in unusually
hot places. In Figure 4 I show a sheet in which the canvas happened to run straight
and to coincide with the other sheets and in which the felt was purposely made wider
than the desired sheet in order that its edges might be turned in as shown. In
Figure 5, I show a sheet in which the canvas and the felt are both turned in but the
paper not.
In order that the cementing material may be more effectively prevented from
running out from between the several layers or sheets, I sometimes run a cord K,
(see Figure 6) into the folded over edge of the sheet, this cord thickens the edge,
throwing out a rib thereon, which if the cord be sufficiently large will rest against
the adjoining sheet, thus more effectively confining the softened cementing material.
The cord also additionally strengthens the edge of the fabric, and it may be incor-
porated with the turned over edges of all the sheets composing the fabric, or of
certain ones only.
Of course two hemmers will be necessary on each side of the machine to turn over
the edges of both the canvas and the felt. Moreover the edge of the paper or other
underlyer may also be turned back upon itself, if this is done it should be turned
up towards the center of the compound sheet. In Figure 6, I show the cord
introduced in the edge of the turned over sheets in a three ply fabric.
In all the forms illustrated and above described, the canvas has the selvage edge
left thereon, that being the controlling feature of my invention.

page_text: My improvement is as applicable to a two ply fabric composed of suitable
material as to a three ply, and I sometimes use an asbestos sheet as the outer or
the under sheet, one or both, thus giving a fire proof quality to the compound
sheet, and an asbestos sheet may also be used as an interinediate sheet in a three
or more ply fabric.
The outer surface or surfaces of my compound sheet may be protected from wear,
and may also be ornamented by any suitable coating, and the compound sheet may
be treated so as to be fire proof.
In the manufacture of the sheets which being less expensive I sometimes employ
instead of the canvas as above stated, I use a pulped or felted sheet having
strands, cords, netting, wire or gauze imbedded therein and apply thereto on one
or both sides other sheets to form the two or more ply compound Roofing Sheet,
one or all of said sheets being waterproofed as before stated.
Figure 10. illustrates an edge view of this form of sheet, the strengthening
textile or gauze material being located centrally in a pulped or felted sheet, and
the sheet so strengthened employed as the central sheet in a compound roofing
sheet having additional sheets on each side thereof, substantially the same as before
stated.
Figure 11. illustrates a similar view of a modified construction, showing a central
sheet having strenthening textile fabric, or cords or wire or gauze like material on
one of its surfaces, and other sheets on each side thereof.
The object of this part of my invention is as above intimated to construct a
compound roofing sheet, compose of a plurality of sheets or layers, which compound
sheet shall possess substantially the characteristics of the roofing and like sheets above
described by me, but which shall be of less cost and capable of more easy manufacture
and yet possess the requisite strength for many uses.
The strengthened pulped or felted sheet will not materially stretch under the
tension incident to manufacturing the compound roofing sheets, thus obviating that
difficulty in the use of canvas, and the edges being straight and even, will run through
the machine evenly and may be easily guided so as accurately to coincide with the
edges of the other sheets composing the compound sheet. It will thus be seen that
by this part of my invention I produce a new article of manufacture which obviates
the defect of lack of strength in the old multiple layer paper sheet and also removes
the objections of cost and difficulty of manufacture of the sheets containing canvas, the
edges of such parts of this strengthened sheet, if any, which project laterally and
also of the paper and felt will be turned in as before explained. It will be found
however that ordinarily the edges of this strengthening sheet made as described will
coincide with the edges of the other sheets.
In Figure 10, I illustrate the compound sheet as made with this improved inner
sheet used instead of the canvas. The textile material, cords or wire gauze
netting B¹ as the case may be is put in the body of the sheet A'. which is made of
any suitable fibrous material by the employment of the well known. pulping process
and paper making machine or by a felting process as desired. I prefer to employ
fibrous asbestos or asbestos and other fibrous material mixed as the stock, but paper,
wood or other stock may be employed for making this sheet, and on the outside
thereof I attach, by the employment of any suitable adhesive material, and on one
or both sides (shown in the drawings on both sides) supplemental or surfacing
sheets of felt, paper or similar material CC preferably using an asbestos sheeting.
In this figure my compound roofing sheet is shown in its completed condition, the
interior sheet being strengthened by the incorporation therewith of the textile or
wire fabric, thus rendering it a very good substitute for the canvas. The entire
compound sheet is waterproofed at any preferred stage of the manufacture by the
employment of suitable materials such as tar, coal tar, pitch, gum, asphaltum, &c.
In Figure 11, I illustrate still another method in which my improved compound
sheets having a strengthened pulp sheet instead of the canvas, may be constructed, i.e.,
the sheet is made as in the case illustrated in Figure 10, excepting that the
strengthening material B' is applied on one side of the interior sheet instead of in

page_text: the middle thereof, and then supplemental layers of suitable material, such as felt,
asbestos sheathing or paper thoroughly waterproofed by treatment with tar, coal tar,
pitch or equivalent substances, as before stated, are attached to the side of the central
sheet A¹ upon and outside of the textile material or wire netting or gauze or cords B'.
The attachment of the several layers of material composing the compound sheet to
each other in all of the above mentioned instances may be by the employment of
suitable cementing materials in addition to the waterproofing substances, but in most
cases the waterproofing substances, being themselves adhesive, will serve this end well.
Of course pressure is applied to the compound sheet to firmly compact the several
layers thereof upon each other.
Both forms of my improved sheet may be rolled up for transportation into a small
compact shape to be unrolled as an entity all complete ready for application to the
roof, when desired for use.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is
First: A compound sheet comprising essentially a plurality of separate sheets of
different materials and of average equal widths, one of them being canvas having a
selvage edge, any excess in width and projecting edges of the canvas being made
straight and equal in width to the other sheets by turning in the edges thereof and
cementing material between the several sheets, substantially as set forth.
Second: A compound sheet comprising essentially a plurality of separate sheets,
having cementing material between them, one or both the edges of either of said
sheets being folded over upon itself thus thickening the edge of the sheet and
interposing a rib between it and the next sheet, whereby the outflowing of the
cementing material is obstructed, substantially as set forth.
Third As a new article of manufacture a flexible compound roofing sheet comprising
essentially a sheet composed of fibrous material having cords or strands integral
therewith and a supplemental sheet externally attached thereto, the whole being
waterproofed substantially as set forth.
Fourth As a new article of manufacture a roofing sheet comprising a plurality of
separate sheets one or more edges whereof are thickened by a cord, wire or strip of
material substantially as set forth.
Fifth A roofing sheet composed of a plurality of separate sheets one of them
being canvas and one of them being wholly or partly asbestos substantially as set
forth.
Sixth: A roofing sheet composed of a plurality of separate sheets one of them
being wholly or partly asbestos and another one a strengthened pulp sheet substantially
as described.
Dated this 10th day of December 1889.
HENRY WARD JOHNS.