Improvements in and in the Manufacture of Sheet Metal Rimmed Covers.
Year: 1891

page_text: Date of Application, 4th Dec., 1891
Complete Specification Left, 5th Sept., 1892-Accepted, 15th Oct., 1892
PROVISIONAL SPECIFICATION.
Improvements in and in the Manufacture of Sheet Metal Rimmed
Covers.
We, HAROLD HOLCROFT, Ironfounder, and ALFRED HILL MOULD, Manager
of Ironfoundry, both of Ettingshall Foundry, Wolverhampton in the County of
Stafford, do hereby declare the nature of this invention to be as follows:-
This invention has for its object to strengthen the rims of sheet metal rimmed
covers; and such object is effected, according to this invention, by covering the
rims each with a ring of sheet metal which passes both above and below the rim
and around the edge thereof.
In carrying out this invention in the case of solid drawn covers, that is to say,
covers which have the rims formed each in one piece of sheet metal with the body,
there is first placed around the metal blank, after it has been drawn in the first
operation in the process of manufacturing into a lid, and previously to the operation
which forms the rim, a sheet metal hoop of such width and in such position that
during the ordinary operation of forming the rim this hoop will be bulged out and
flattened up in the same manner as the ordinary rims, and will thus form a complete
outer thickness to the ordinary or inner rim. It is preferred, however, to give an
initial bulge to the hoop before placing it around the drawn blank, in order to
facilitate the subsequent operation of forming a rim of double thickness, and an
initial bulge may be given also to the portion of the blank which is intended to form
the ordinary or inner rim after the bulged hoop has been placed therearound, in
order to still further facilitate the operation of forming the rim.
The hoops for the purpose of being utilized as described, may be produced by
first drawing sheet metal into cylindrical form and then cutting off rings thereof
for the hoops. A convenient method, however, of producing these hoops is to
provide blanks of larger diameter than usual for the lids, and to draw them
sufficiently deeper than required for forming ordinary single rimmed lids to allow of
a ring being cut off from the end for the hoop; and in such case the hoops may
be subsequently enlarged so as to be of the proper diameter for the purpose
required.
The tools employed in bulging out the metal and forming a rim press, of course,
against the edges of the hoop and force out the metal to form the outer thickness.
In the case of strengthening made-up lids, the sheet metal rings around the rims
thereof are formed by spinning hoops over the rims; and the hoops may be spin
over the rims of solid drawn lids, if desired, instead of being shaped in place as the
rims themselves are formed in the manner above described.
Dated this 3rd day of December 1891
STEPHEN WATKINS,
Wolverhampton, Agent for the Applicants.
COMPLETE SPECIFICATION.
Improvements in and in the Manufacture of Sheet Metal Rimmed
Covers.
We, HAROLD HOLCROFT, Ironfounder, and ALFRED HILL MOULD, Manager
of Ironfoundry, both of Ettingshall Foundry, Wolverhampton in the County of
Stafford, 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 :-
This invention has for its object to strengthen the rims of sheet metal rimmed

page_text: covers; and such object is effected, according to this invention, by covering the
rims each with a ring of sheet metal which passés both above and below the rim
and around the edge thereof.
It is
In carrying out this invention in the case of solid drawn covers, that is to say,
covers which have the rims formed each in one piece of sheet metal with the body,
there is first placed around the metal blank, after it has been drawn into a cup-shape
in the first operation in the process of manufacturing it into a lid, and previously
to the operation which completes the rim, a sheet metal hoop of such width.and in
such position that during the ordinary operation of completing the rim this hoop
will be bulged out and flattened up in the same manner as the ordinary riin, and
will thus form a complete outer thickness to the ordinary or inner rim.
preferred, however, to give an initial bulge to the hoop before placing it around the
drawn blank, in order to facilitate the subsequent operation of forming a double.
rii, and an initial bulge is preferably given (as is usual) to the portion of the..
blank which is intended to form the ordinary or inner rim, after the bulged hoop
has been placed therearound, in order to still further facilitate the operation of
forming the double rim. The hoops, for the purpose of being utilized as described,
may be produced by first drawing sheet metal into cylindrical form and then cutting
off rings thereof for the hoops. A convenient method, however, of producing
these hoops is to provide blanks of larger diameter than usual for the lids, and to
draw them sufficiently deeper than required for forming ordinary single rimmed lids
to allow of a ring being cut off from the end of each cup for a hoop; and in such case
the hoops are subsequently enlarged so as to be of the proper diameter for the
purpose required.
The flanging tools employed in bulging out (or further bulging out) the metal
and forming a double or encased rim press, of course, at first against the edges of
the hoop and thus force out the metal thereof to form the outer thickness or casing
of the rim at the same time that the metal for the ordinary or inner rim is being
forced out by such tools; and the inner and outer rims are flattened up together by.
such tools, just in the manner in which the two thicknesses of metal of a single
rim are ordinarily flattened up.
In the case of strengthening made-up lids, the sheet metal rings around the rims
thereof are formed by spinning hoops over the rims; and the hoops may be spun
over the rims of solid drawn lids, if desired, instead of being shaped in place as
the rims are formed in the manner above described.
In order that this invention and the means of carrying it out in practice may be
clearly understood, we will now proceed to describe the same with reference to the
accompanying drawings which illustrate the invention as applied to the manufacture
of a sheet metal saucepan lid.
Figure I represents in section a sheet metal blank A for a saucepan lid drawn,
into a cup-shape in the manner usual in the manufacture of solid drawn lids; hut.
in this instance the cup is shewn to be deeper so as to allow for a hoop to be cut
therefrom, as indicated by broken line; to be used as a strengthening hoop for
the lid or, more conveniently (as will hereinafter appear) for a lid made from another
blank..
Figure 2 represents in vertical section, taken longitudinally of the axis, the
cup A shewn by Figure 1 as inserted within a chuck B which in use is screwed
on to a lathe spindle head. This chuck is of the character of those used in lathes.
in which cups for solid drawn lids are usually chucked for giving them the
initial bulging for the rims, but an annular rebate (rabbet) a is, preferably, formed
around the interior of the chuck as shewn, and previously to inserting the cup
within the chuck, a sheet metal hoop 6 formed trough-shaped or bulged in section,
as shewn, and of an interior diameter corresponding to the exterior diameter of
the cup, is inserted within the rebate. The cup is first pushed by hand some
distance into the hoop, the rounded corner of the cup readily admitting thereof,
and the cup is then pushed up into the position shewn within the chuck by means
of the head C which is of the usual character of those employed with such chucks

page_text: used for the purpose aforesaid. The outer edge of the cup is first trimmed up
true by means of rotary cutters in a manner well understood, and a hoop is then
cut off from the cup, by means of such rotary cutters, to a width from the
trimmed outer edge thereof indicated by the dotted line i, and such hoop is treated
in the manner subsequently described, and is used as the strengthening hoop for
the rim of a lid made from another blank.
Figure 3 corresponds in all respects with Figure 2, except that the cup is shewn,
after a hoop has been cut off from the end thereof, and with a portion thereof
bulged or spun out into the hollow of the hoop b. This bulging out of the
portion of the cup may be effected by means of a rounded-edged roller. pressed
up against the inside of the cup, in the manner in which such cups are usually
bulged out for the rim..
It is not essential to form a rebate a as described in the chuck, as the hoop may
he placed around the cup previously to the cup being inserted within the chuck,
and in such case will be held sufficiently by the cup alone while the groove dis
formed.
We have not thought it necessary to illustrate the lathe by which the chuck
and head are carried, or the rotary cutters, or bulging roller, as they are of the
character of such parts used for corresponding operations in the manufacture of
solid drawn sheet metal lids, and their use will therefore be readily understood by
persons having a knowledge of such mechanism: It may, however, be explained
that convenient mechanism for the purpose consists of a lathe in which the cutters,
and lever on the end of which the bulging roller is mounted, are carried by a slide
or saddle capable of being moved towards and from the chuck (in the manner in
which the saddle carrying cutters for trimming the outer edges of the cups is
operated in existing machinery for the purpose, or in other convenient manner) and
in which the head C is mounted to be moved independently of the cutter and.
roller, as in the case of some of the existing machines used in the manufacture of
solid drawn rimmed lids. The slide or saddle carrying the cutters and roller is
first brought up against a movable stop, that the cutters may be applied in trimming
'up the edge of the cup; and such stop is moved clear, and the slide is then moved.
up against a fixed stop, in order that the cutters may be applied to cut off a hoop
from the cup, and the roller be used for bulging out a portion of the interior of
the cup into the hollow of the surrounding hoop. If the cups are not prepared.
with portions to be cut off therefrom to. form the hoops, but the hoops are formed,
as they may be, independently of the cups, the machines at present in use for
trimming the edges of the cups and bulging out the portions to form the rims may
be used without any alteration or modification, as no movable stop is required in
such case.
The cup A, with the hoop b therearound, as shewn by. Figure. 3, is next
transferred to a press fitted with the usual flanging dies or tools used in forming
the rims of solid drawn sheet metal lids. The upper and lower edges of the
hoop bare pressed between the upper and lower dies, respectively, with the effect
of doubling and flattening out such hoop together with the portion d of the cup to
form the rim of the lid, the metal of the hoop passing both above and below the
rim and around the edge thereof, as shewn by Figure 4.
When the hoops are cut off from the ends of the cups, as described, it is necessary
to draw them somewhat, and this is readily accomplished, and the desired sectional
shape given at the same time, by means of a pair of drawing and grooving rolls
such as shewn by Figures 5 and 6, of which Figure 5 is a side elevation and
Figure 6 an end elevation. One of the rolls N, preferably the smaller, is carried
on the inner end of a handle lever O pivoted at k; and the other roll P is fixed on
the projecting end of a spindle R which is mounted in fixed bearings and is driven
by suitable gearing from any convenient source of power. When a hoop 6 is to be
placed between the rolls, the roll N is moved outwards from the roll P; and when
the hoop has been placed in position around the roll P the roll N is pressed against
the hoop which is, of course, rolled between the rolls.

page_text: Figure 7 shews, in section, a method of spinning a hoop around the rim of a
made-up lid, or if desired of a solid drawn lid. The hoop b is first made of an
angle section (by drawing a blank with a rim or flange, and then cutting out the
middle of the blank, or in other convenient manner) and is then held with the
flange against a chuck while the flange 62 is spun over into the shape shewn by
broken line; that is to say, such hoop spun over just as the edge of the main
part of the lid is usually spun over the flange of the separately-made angle ring, in
the manufacture of made
up lids.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :
1. A. sheet metal rimmed cover having the rim covered with a ring of sheet metal
which passes both above and below the rim and around the edge thereof, sub-
stantially as described.
2. In the manufacture of solid drawn sheet metal rimmed covers, placing hoops
around the portions of the cups from which the rims are to be formed, and then
doubling and flattening down such hoops together with such portions of the cups,
substantially as described.
3. In the manufacture of solid drawn sheet metal rimmed covers; placing hoops,
which have been previously formed to a trough section, around the portions of
the cups from which the rims are to be formed, and then doubling and flattening
down such hoops together with such portions of the cups, substantially as described.
4. In the manufacture of solid drawn sheet metal rimmed covers, placing hoops,
which have been previously formed to a trough section, around the portions of the
cups from which the rims are to be formed, then giving an initial bulge to such
portions, and finally doubling and flattening down such boops together with such
portions of the cups, substantially as described.
5. In the manufacture of solid drawn sheet metal rimmed lids to be strengthened
with strengthening rings around the rims as described, cutting off hoops, to form
rings for such purpose, from the sheet metal cups formed by the drawing through
process employed in such manufacture, substantially as described.
6. The methods of manufacturing sheet metal rimmed covers, substantially as
described and shewn by the drawings herewith, for the purpose set forth.
Dated this 2nd day of September 1892.
STEPHEN WATKINS,
Wolverhampton, Agent for the Applicants.