Year: 1887

page_text: Date of Application, 11th Jan., 1887
Specification Accepted, 9th Sept., 1887.
I, EDWARD SMALL, of Baltimore, Maryland, United States of America, gentleman,
do hereby declare the nature of this invention 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 an improved tool for interlocking edges of sheet-metal
plates.
The object is to provide a tool which will form a seam by the simple operation of
sliding the tool along the edges of two plates.
:-
The invention is illustrated in the drawing hereto annexed in which :-
Figure 1 is a view showing the tool applied to the side-seam of a can-body; the
side of the tool is partly broken to show the plate edges.
Figures 2 and 3 show the can-body held by a clamp in such manner as to firmly
keep the plate-edges in position.
Figure 4 is a face view of the seaming tool.
Figure 5 is a side view of the same.
Figure 6 is a view of the tool showing the large end of the tapered groove.
Figure 7 is a central cross-section of the tool.
Figure 8 is a view of the tool showing the small end of the groove.
Figure 9 is a cross-section of the tool near the small end of the groove, showing two
plates of sheet-metal nearly seamed.
Figure 10 is a side view of a modified form of seaming tool.
Figure 11 shows two plates of sheet-metal having their edges bent up preparatory
to being seamed.
Figure 12 is a view of two plates of sheet-metal, the edges of which are not bent,
but are in position to be held by clamps preparatory to being seamed.
Figures 13 and 14 show two plates united by a seam made by the tool.
Figures 15 and 16 show two plates united by a seam of modified form (a flat seam)
made by the tool.
Figure 17 shows the end of the tool wherefrom the flat seam issues.

page_text: The letter A designates the metal block which composes the body of the tool. In
the present instance the body of the tool has in general a rectangular shape, but it
may be shaped otherwise, as may best suit special work. A tapering or gradually-
contracted groove, b, is in the face-side of the body, its largest part forms a large
opening, , at one end of the body, and its smallest part forms a small opening, 2, at
the other end. In cross-section the shape of the groove is partly half-circular, or
somewhat exceeding a half circle. While the groove has a regular taper from the
large opening, ', its position in the body-block is such that the half circle of that part
of the groove from the large opening to about half its length, merges in a flat side, c,
which is at right angles to the face, as shown in Figure 6. This flat side, c, at and
from the large opening as far as said flat side extends, and the continuation there-
from of the groove to the small opening, 3, together, form on the face-side of the tool
a straight line edge, c', from end to end of the body-block. Opposite the said straight-
line edge is the lip edge, d, which finishes the coiling or curling of the seam parts. In
the present instance a head, E, is attached or is integral with the body-block; this
head has under cut inclined sides, e, thereby forming the one-half of a dove-tail, and
adapting the tool to be secured to any suitable holder, F, which may have the counter-
part or other half of a like dove-tail. In the illustration, Figure 1, the seam to be
formed is that extending lengthwise of a can-body. Suitable clamps, L, are shown to
firmly hold the can-body and keep the edges in position while the tool operates
thereon. Whatever form the metal plate may have, whether flat sheets formed up
square for a box-body, or cylindrical, like that shown for a can-body, suitable clamps
must be employed to firmly hold the parts to be joined. The edges of the metal plates
to be united must be brought together side to side, one of the edges, may by preference
project beyond the other, as shown the part of the plates adjacent to the edges
require to be firmly held or stayed to prevent the edges from retreating when the
seaming tool is forced along. The tool is then advanced, the large opening, b', fore-
most, as indicated by the arrow, in a direction corresponding to that in which the
plate-edges, g, h, extend. Instead of advancing the tool, and holding stationary the
plate-edges, it is obvious the plate-edges may be advanced and the tool hold stationary.
The plate-edges, g, h, enter the large opening, bl, of the tool, at first resting against or
in contact with the flat side, c, thereof. The straight-line edge, c', of the tool must
be parallel with the plate-edges, g, h. In those cases where the edge of one plate
projects beyond the other, the longer edge of the plate should be next to the said flat
side, c, of the tool.
As the tool or plate edges advance (whichever may be moved) the plate edge
encounters the circular part of the gradually-contracted groove, and as the tool is so
firmly held by its holder that it can not deviate, and the plates are so stayed that their
edges can not retreat, the result is the plate-edges are forced to curl or coil, by the
action of the largest part of the groove, and then this coil by the progressive or con-
tinued sliding of the tool taking place, is gradually tightened or compressed by the
action of the smaller part of the tapered groove, until said tightened coil passes out
the smaller opening, 63, in a finished state. This operation completely interlocks the
plate-edges by coiling one edge over the other, the finished seam, i, being seen in
Figures 1, 13 and 14.
It is not essential that the finishing-lip edge, d, at the extreme small end of the
groove should project so far toward the straight line, c', as shown in the drawing; a
less projection of this edge will produce satisfactory results.
I contemplate a wide range of work for this tool; it is adapted for uniting sheet-
metal plates of any kind, such as tin plates, ordinary sheet-iron and copper plates, and
even iron and steel plates as thick as those commonly used for boilers. The tool here
shown is suited for straight seams, but by an obvious change it may be adapted for
forming the seams on curved or cylindrical bodies.
Instead of a seam of rounded shape, like that seen in Figures 1, 13 and 14, a flat
seam may be made, like that seen in Figures 15 and 16. This form of seam may be
produced by providing the tool at the small end of the groove with a terminal of flat
shape, as at, n, in Figure 17,

page_text: It is not essential that the tool-block have a gradually-contracted groove continuous
from one end of the block to the other. This is illustrated in Figure 10, where the
block has three sections 1, 2, 3, and an opening, 6', partly-circular with a flat side, c,
is in block 1; and the smallest opening, b, partly circular with a finishing lip, d, on
the side opposite that whereon the flat side is located, is in block, 3; while the middle
block, 2, has an opening corresponding to that seen in the section-viow Figure 7.
The several openings in parts 1, 2, 3 of the block gradually contract in size. It is
possible to do the work of seaming with only two sections, the first, 1, and the last 3.
Having now particularly described and ascertained the nature of my said invention
and in what manner the same is to be performed, 1 declare that what I claim is :-
1st. A sheet-metal seaming tool consisting of a body-block having in the face-side
a tapering or gradually contracted groove partly circular in cross-section, whereby
the tool is adapted to form a seam by sliding along the sheet-metal edges, as set
forth.
2d. A sheet-metal seaming tool consisting of a body-block having in the face-side a
tapering groove partly circular in cross-section, and extending from end to end of the
body-block, as set forth.
3d. A sheet-metal seaming tool, consisting of a body-block having in the face-side
a tapering groove partly circular in cross-section with a straight-line edge, c¹, at one
side of the groove, and the finishing lip edge, d, at the opposite side, as set forth.
4th. A tool for interlocking the edges of two sheet-metal plates by coiling the edge
of one over the other, consisting of a body-block having an opening, b, partly circular
with a flat side, c', and a smaller opening, 62, partly circular with a finishing lip, d, on
the side opposite that where the flat side is, as set forth.
Dated this 28th day of December 1886.