IMPROVEMENTS IN MACHINERY FOR FORMING THE JOINTS OF TIN OR SHEET-METAL VESSELS
Year: 1881

page_text: LETTERS PATENT to Martin Benson, of No. 52, Chancery Lane, London, for
an Invention of "IMPROVEMENTS IN MACHINERY FOR FORMING THE
JOINTS OF TIN OR SHEET-METAL VESSELS." A. communication from abroad
by Alton Hugh Fanchers, of Brooklyn, in the County of Kings, State of
New York, United States of North America.
COMPLETE SPECIFICATION filed by the said Martin Benson at the Office
of the Commissioners of Patents on the 2nd September 1881.
"
MARTIN BENSON, of No. 52, Chancery Lane, London. IMPROVEMENTS IN
MACHINERY FOR FORMING THE JOINTS OF TIN OR SHEET METAL VESSELS."
A communication from abroad by Alton Hugh Fanchers, of Brooklyn, in the
County of Kings, State of New York, United States of North America.
The object of this Invention is to simplify the mechanical operation necessary
in double seaming sheet metal, and also to prevent the strain upon the metal
during the formation of the seam, which in the use of methods hitherto known
has necessitated the use of the toughest and best qualities of sheet metal in wares
made with double seams so called.
The ordinary methods of forming double seams in sheet metal is well known to
tin smiths, involves no less than four different mechanical operations for forming
and closing the seam, and the action upon the metal is such that short bends and
severe strain along narrow lines is inherent in the operation, so that any inferior
quality of metal is liable to fracture and thereby cause not only the waste of
labor expended in forming the joint but also the loss of the material itself.
By my Invention aforesaid the number of steps or operations necessary in the
formation of the seam is reduced to two, both of which may be performed by the
single movement of a suitably arranged operating lever or equivalent device, and
by my said Invention furthermore I insure the avoidance of sharp bends in the
metal, so that the strain thereon is reduced to practically nothing. In the practice.
FDC:71

page_text: of my said Invention the suitably flanged edges of the parts to be joined are first
united by false wiring, so termed, thereby first forming the joint circular or
semi-circular in its cross section, one of the edges being coiled within the other.
This done, the joint formed by false wiring, as just described, is flattened to the
usual external configuration, thereby insuring the conjunction in close contact of
the coiled edges, and forming a tight double seamed joint by an operation which
causes practically no strain upon the joined edges of the metal, and thereby
enables a cheaper material to be employed in the manufacture of the article than
has hitherto been possible in double seained articles of sheet metal, it being well
understood in the trade that the necessity of a superior quality of sheet metal in
the manufacture of cans, &c., has arisen, not from any need of the strength or
toughness of the superior quality in the article itself, but in the necessity of
insuring immunity from fracture of the flanged edges during the operation of
joining the same and forming the double seam. This Invention comprises not only
a novel mechanical process, herein before indicated in brief, but also certain novel
combinations of parts for effectually carrying into effect the said process. Fig. 1 is
a vertical sectional view of an apparatus embraced in my said Invention, and
Fig. 2 is a side elevation in a plane at right angles to that of Fig. 1; Fig. 3 is a
horizontal sectional view taken in line x, x, of Fig. 2, and Figs. 4 and 5 are
detailed views on a larger scale illustrating the action of the folding mechanism
upon the flanged edges of the metal in the formation of the seam. In. the
Drawings the Invention is illustrated as applied in the manufacture of sheet metal
cans, in which circular heads are fitted and scamed to cylindrical bodies. The
bodies A are primarily formed at their ends with a radial circumferential flanges a,
as shown at the lower part of the body A, as represented in Fig. 1. The ends B
are stamped or otherwise suitably brought to the shape, also indicated at the upper
and lower end of the body A, as represented in said Fig. 1, that is to say, with the
cup shaped flange c¹, so that the central or concave portion of the end B-fits within
the adjacent end of the body A, with the flange c' curving around the flange a of
the body. The body A and ends B are brought to the shape just indicated by any
of the means well known in the trade for forming seam flanges in sheet metal, and
which require no specific description here. The body A, being provided with the
ends B, is placed within a chuck composed of two axially rotating jaws C and D,
one of which C is provided upon the inner end of the shaft E, arranged in
bearings b, so as to be capable of rotation, but sustained against any longitudinal
movement by suitable shoulders provided_on_the_shaft adjacent to the
bearings b.
The lower jaw D is attached to the upper end of the shaft F, which is axially
coincident with the shaft E, and which rotates in suitable fixed bearings c, which,
like the bearings b, are attached to the supporting frame of the apparatus. But
the shaft F, instead of being held against longitudinal movement, is so arranged
within its bearings as to be capable of such movement, and, as represented in the
Drawings, descends together with the jaw D by its own gravity, and must be
designedly moved and sustained in an upward direction. This latter is provided
for by means of a lever G, which, pivotted at one end, as shown at f in Fig. 2, is
provided at its other extremity with a step g, into which fits the lower end of the
shaft F, and vertical movement is given to the lever G by the treadle lever H
connected with the aforesaid lever G by a suitable link h, so that on pressing
downward upon the outer or treadle end of the treadle lever H the step g is moved
upward and consequently moves upward the shaft F and jaw D against the
lowermost end of the body A, the uppermost ends B being in like manner brought
against the jaw C. It will be noticed that the jaws C and D fitted within the
cavities formed in the outermost surfaces of the ends B (the heads of the body A
being securely gripped between the said two jaws C and D) are permitted to have
a rotary movement around the axis of the shafts E and F, and are at the same
time held against any vertical movement; a rotary movement being thus given to
the shaft E by means of a suitable belt on a pulley i, the shafts E and F, the

page_text: jaws C and D, the body A and ends B, all rotate in unison around the axis of the
shafts aforesaid.
As represented in the Drawing the mechanism for folding the flanges a, cl, together
are represented only as applied at one end of the can formed by the body A and
ends B, but it is to be understood that the same apparatus, which in the Drawings
is represented at one end only of the can, may when desired be applied at both, so
that both ends of the can, or in other words the double seams at the two ends, may
be formed without removing the body and ends from the chucks, but as inasmuch
as this duplication (of the parts hereinafter described for folding the flanges
together and forming the double seam) requires simply mechanical judgment, I
have not considered it necessary to illustrate the parts in duplicate, and more
especially as the construction of the said parts and their arrangement in the
formation of the seam is clearly indicated in the Drawings, and their application to
operate at both ends of the can instead of one is easily within the knowledge of
any mechanic ordinarily skilled in the trade. Supported upon a suitably fixed
bracket I or other appropriate support is a horizontal lever J, which has its inner
end extended laterally, or, if preferred, forked, in order to provide suitable bearings
for two folding rolls K and L. The lever J is so arranged that the rolls K and L
will be in substantially the same plane as the flanges a and c to be joined, as
indicated in Figs. 1 and 2, and on a larger scale in Figs. 4 and 5. Each of the
rolls K and L should be formed with a flange m, in order that the said flange in
the operation herein explained may travel across and above the corresponding
upper edge of the adjacent ends B, the object of this being merely to facilitate the
retention of the rolls in position during their actual contact with the metal in the
formation of the joint, and also to prevent the metal while being folded from
creeping vertically out of the desired position. The essential feature of the
rolls K and L is this:-That each is circumferentially grooved, but the groove in
one different from that of the other; thus, for example, the groove shown at n,
Fig. 4, of the roll K is semicircular in its cross section, so that when brought in
contact with the flanges a, c', it will operate to fold then one within the other to
form the partial joint C to substantially a circular cross section, as represented
in Fig. 4, whereas the groove shown at 7, Fig. 5, of the roll L is of such form as to
flatten the circular and partially formed joint just hereinbefore specified, and bring
the same into a flattened, compact, and so to speak, solid condition, as represented
in Fig. 5. The lever J and the rolls K and L carried thereon are placed in such
proximity to and relation with the jaw C (and with the jaw D when both ends of
the can are to be double seamed without removing same from the chuck), and by
moving the lever J around its pivot S the roll K moving in the direction indicated
by the arrow in Fig. 3, may be brought against the flange c while the parts are
being rapidly rotated, as hereinbefore explained, while the roll K is thus sweeping
in the direction indicated by the arrow in contact with the flange c¹, it causes the
said flange c' and also the flange a within it to be brought over into a semicircular
or circular forin by the pressing action exerted upon the metal by the grooved
periphery of the said roll K; the result being that the two flanges are folded
inward one within the other into the half formed joint of semicircular or circular
cross section, indicated by Fig. 4. No sooner has the roll K passed out of contact
(by diverging in its circular path from that of the circumference of the end B) than
the other roll L is in a similar manner brought in contact with the half formed
joint, just described, by the continued moveinent of the lever J, the result of this
being the grooved periphery of the said roll L acts upon the half formed semi-
circular or circular joint above described, and presses the same to the close flattened
contour and relatively solid condition represented in Fig. 5, so that by the
operation, first of the roll K, second, of the roll L (being but two operations
following in rapid succession), the two flanges are united in a solid, compact, and
strong joint, both of the said operations being performed during the rotation of
the can by a single movement of the lever J, and inasmuch as the action of these
two rolls K and L is so exerted as to compress the metal upon itself and to turn it

page_text: gradually with the slightest possible acuteness in the folding, it follows that no
material breaking strain is exerted upon the flanges while they are being bent and
folded to form the double seam. Inasmuch as the object of the lever J is to bring
the rolls K and L one after the other in suitable relation with the flanges of the
sheet metal parts to be united, it follows that any device, for example, a slide
which will give the same movement to the said rolls, with reference to the said
Hanges of the parts to be united will be merely the equivalent of the said
lever.
Having described the manner of constructing and applying my said Invention,
what I claim is,-
1st. The herein before described mechanical process of forming double seams in
sheet metal by first forming a joint or sean circular or semicircular in its cross
section, and then flattening said joint to a flattened configuration, thus pressing the
interlocked edges into close contact with each other, all substantially as and for the
purpose herein set forth.
2nd. In an apparatus for double seaming articles of sheet metal, a chuck for
carrying the parts to be united in combination with the roll K having a semi-
circular groove in its periphery, and a roll L having a flat bottomed groove in its
periphery, the said parts being arranged in relation with each other to first form an
interlocked seam of semicircular cross sections, and to subsequently flatten said
seam or joint, substantially as and for the purpose herein set forth.
3rd. The combination of the chuck composed of the two jaws C and D capable
of rotating in the same axial line, and the circumferentially grooved rolls K and L
carried upon the lever J, whereby the said rolls may be brought to act in succession
upon the flanges of the parts pressed or held between the jaws of the said chuck,
substantially as and for the purpose set forth.
.
4th. The combination of the following clements, namely, a chuck constructed to
clasp together the parts to be united, a treadle and adjustable step for actuating
the said chuck to grip and release the said parts, a roll for folding the flanges of
the parts to be united into a joint or seain of a circular or semicircular cross
section, a roll for compressing said joint into a flat and tight condition, and a
lever or equivalent device for causing the rolls aforesaid to operate one after the
other upon the flanges of the parts to be united, the whole constructed, combined,
and arranged for joint use and operation,. substantially as and for the purpose
herein set forth.
-In-witness-whereof,-1,-the-said-Martin-Benson, have hereunto set my hand
and scal, this Second day of September, in the year of our Lord 1881.