AN IMPROVEMENT IN THE MANUFACTURE OF HOLLOW METAL KNOBS, FOR THE HANDLES OF DOOR AND OTHER LOCKS
Year: 1842

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, DANIEL
GREENFIELD, the elder, of Birmingham, in the County of Warwick, Brass-
founder, send greeting.
WHEREAS I did by petition humbly represent unto Her present most
Excellent Majesty Queen Victoria that I had invented "AN IMPROVEMENT
IN THE MANUFACTURE OF HOLLOW METAL KNOBS, FOR THE HANDLES OF DOOR AND
OTHER LOCKS;" and Her said Majesty, being willing to give encouragement
to all arts and inventions which may be for the public good, was graciously
pleased, by Her Royal Letters Patent under the Great Seal of the United
Kingdom of Great Britain and Ireland, bearing date at Westminster, the
Twenty-first day of February (One thousand eight hundred and forty-two),
in the fifth year of Her reign, for Herself, Her heirs and successors, to give
and grant unto me, the said Daniel Greenfield, my executors, administrators,
and assigns, Her special licence, full power, sole privilege and authority,
that I or they, by myself or themselves, or by my or their deputies, servants,
or agents, or such others as I or they should agree with, and no others,
during the term of fourteen years from the date of the said Letters Patent,
should and lawfully might make, use, exercise, and vend my said Invention
within that part of Her said Majesty's Dominions called England, Her
Dominion of Wales, and Town of Berwick-upon-Tweed, in such manner as
to me, my executors, administrators, and assigns, shall seem meet, and as

page_text: that I or they shall enjoy the whole profit and advantage arising by reason
of the said Invention during the said term of fourteen years; and for that
ond Her said Majesty requires and strictly commands all Her subjects what-
soever, within England, Wales, and Berwick-upon-Tweed, aforesaid, that they
shall not, neither directly nor indirectly, make, use, or put in practice my said
Invention, or any part thereof, nor in anywise counterfeit, imitate, or resemble
the same, nor make any addition thereunto or subtraction therefrom, whereby
to pretend himself or themselves to be the inventor or inventors thereof:
and whereas the said Letters Patent contain a proviso, obliging me, tho
said Daniel Greenfield, particularly to describe and ascertain the nature of
my said Invention, and in what manner the same is to be performed, by an
instrument in writing under my hand and seal, and to cause the same to
be inrolled in fer Majesty's High Court of Chancery within six calendar
months next and immediately after the date of the said Letters Patent, as
in and by the same, (reference being thereunto had), will more fully and at
large appear.
NOW KNOW YE, that in compliance with the said proviso, 1, the said
Daniel Greenfield, do hereby declare that my said Invention is described
and ascertained in mauner following, and by the aid of the Sheet of Drawings
hereunto annexed (that is to say) :—
My said improvement in the manufacture of hollow metal knobs, for the
handles of door and other locks, consists in applying an interior lining of
hollow iron within the brass or other metal (such, for instance, as German
silver), whereof the exterior surface of such knobs is or may be composel, in
order by such interior lining of hollow iron to give support and firmness to the
said brass or other metal, which constitutes the said exterior surface, even
although such brass or other metal may be so thin as that it would be liable to
injure from accidental blows if it were not supported by such interior lining of
iron. And by means of my improvement hollow metal knobs, of great strength
and durability, may be manufactured with economy, of the brass or other
metal, whereof the exterior surface of such knobs is or may be composed.
The process of manufacturing hollow metal knobs according to my said
improvement, is as follows:-First, for preparing the hollow iron lining for
the ball part of the knob, a circular disk of suitable size, according to the size
of the knob intended to be made, is cut out of sheet or rolled iron of suitable
thickness, by the usual mode of cutting out with a fly-press and suitable tools
of the kind called a cutting out punch and bolster. The said circular disk is
shewn edgeways at 1 in the Drawing, which shews the diameter and thickness

page_text: of the disk suitable to be used in the making of a hollow knob of the size
shewn at Z in the Drawing. The circular disk 1, of iron plate, being well
annealed by fire, is then pressed from its flat state to the shape of a shallow
concave disk 2, (like a saucer), by forcing it into a concave die, with a
corresponding tool forced upon the iron plate by power of a fly-press, or of a
stamp, the disk or saucer 2, so formed, is afterwards rendered more concave,
as represented at 3, by subjecting it to a similar operation of pressuro in
another die, with a corresponding tool, and by proceeding in that manner the
same piece of metal which was at first a flat circular disk 1, is rendered by
degrees more and more concave, by submitting it to a series of several such
operations of forcing the metal into a succession of dies, with corresponding tools
forced by a fly-press or by a stamp, so as to give the said piece of metal,
successively, all the different forms represented at 2, 3, 4, 5, 6, 7, 8, 9, and 10,
in the Drawing, one after another until the form of a deep cup 10, is obtained.
The mode of performing the said series of operations, and the dies and tools to
be employed therefor, as well as the fly-press or the stamp, do not require any
particular description, being the same as is well known and commonly
practiced in the manufacture of hollow knobs of the ordinary kind which are
made from brass plate without iron, the only difference being that the said
series of operations, above described, is performed upon iron plate instead of
brass plate; and in consequence of iron being less ductile than brass, the iron
must go through a sufficient number of operations in succession which give it
the forms represented in the Drawing, and enable it to be brought to the form
of a deep cup 10, without risk of cracking the iron, and the iron must be
annealed by fire from time to time, as it may require, at suitable stages in the
course of going through the said series of operations. About two or three times
of annealing during the course will be sufficient. Then in like manner, for
preparing the brass or other metal, (such, for instance, as German silver),
which is to form the exterior surface of the ball part of the knob, a square
piece of thin sheet brass, or other metal of a suitable size, is cut out with
shears; and then that square piece is stamped in the same manner as above
described, respecting the iron, by a like series of operations performed in the
same or similar dies, and with tools corresponding thereto, except that in
consequence of the ductility of brass or Gernian silver, it is not requisite to
subject the same to so many successive operations as before described for iron,
but the brass being properly annealed may be pressed at once from the flat
state to the form 8, and then to the forms 5 and 7 and 9, in succession, anil
then by a last operation to the form 11, which is corresponding to 10, and

page_text: very nearly the same, except being so much larger as that the interior
concavity of 11 will fit the exterior convexity of 10. And noto.-The modo
abovo described of preparing the deep cup 11, of brass or other metal, is the
same as is usually practiced in the manufacture of hollow knobs of the
ordinary kind, which are made from brass plate without iron, except that
the plate of brass or other metal may, in manufacturing according to my
improvement, be thinner if desired than could with proprioty be used in
manufacturing knobs of the ordinary kind of brass plate without iron. And
although I have mentioned a fly-press for forcing the tools and pressing the
iron and the brass plate into the dies, it is to be understood that a stamp
which operates by the falling of a heavy weight, may be used instead of a
fly-press, at the option of the workman. The deep iron cup 10, and the
corresponding deep cup 11, of thin brass or other metal, being thus formed,
the iron cup 10 is put into the brass cup 11, the border edge of the latter
being first clipped round with a pair of clipping tools to remove the superfluous
metal, bringing the edges a, a, of the two cups 10 and 11 nearly to correspond.
Then the two cups together, (the iron 10 being within the brass ono 11, as
shewn in section at A), are forced through a circular hole in a steel ring
by a corresponding tool, urged by a fly-press, and thereby the sides of
the two cups are drawn in or contracted to a cylindrical form, as shown
in section at B, and the brass is caused to adhere very closely to the iron.
The circular border edge of the compound cup B of brass, lined with iron, is
then cut round with shears, so as to reduce the iron and the brass to an exact
correspondence, and so as to give a true border odge b, b, to the compound
cup B. Then the compound cup B is closed in or contracted at the border
edgo around the mouth (and at the parts of the sides adjacent to that mouth)
to the form shewn at C, the mouth c, c, when so contracted, being of suitable
size to receive the enlarged part e, e, of the neck part 14 of tho knob. The
said closing in of the mouth c, c, is performed in the usual manner of closing
in, as practised in the manufacture of hollow knobs from brass plate without
iron, that is, by means of a pair of closing tools in the fly press, which force the
large open mouth b, b, of the cup B into a concave hollow die, of a suitable
concave shape, for gathering in the border edge c, c, around the mouth (and
also part of the sides adjacent to the mouth) to the shape shown at C. The
preparation of the hollow ball part of the knob is now completed, except that
if the border edge c, c, around the contracted mouth of C is not quite true and
smooth, it may be made so, by means of a revolving conical tool furnished with
cutting teeth around its conical surface, such tool being of the nature of a

page_text: countersink of large size. That tool or countersink may be mounted in a lathe,
by affixing it at the end of the revolving spindle of the lathe, so as that the said
countersink will be turned round, and by holding the hollow ball C in the hand
and applying the contracted mouth c, c, to such revolving countersink for an
instant, the border edge c, c, of that mouth will be cut by the revolving counter-
sink, and may thereby be rendered truly circular and smooth, and bevilled
internally to suit the dotted lines in C, which dotted lines may represent the
conical form of the cutting part of the said countersink. If the cutting of the.
border edge b, b, of the compound cup B with shears, as before mentioned, has
been truly performed (or it may be filed smooth and true after cutting with
shears), then the border c, c, of the contracted mouth of C, will of itself, assume
a proper bevil shape during the contraction, and will continue to be sufficiently
smooth and true without cutting that border edge c, c, by a countersink, which
may therefore be used or not, according as is found requisite. Then, for preparing
the neck part of the knob, the hollow iron part for lining the neck is to be
somewhat of the shape and size represented at 14, and may be made of cast-
iron cast into the intended shape, with a square hole through the centre of it,
and a groove around each end of it, at d, d, and at e, e. And note.-The cast-
iron 14 may (after being so cast) be subjected to the ordinary process for con-
verting small castings of cast-iron into malleable iron, or into what is called
converted malleable iron, if it is preferred to so convert the castings for the said
pieces 14. The said process being well known, and in ordinary use for so
converting cast-iron, need not be described. And, as to the aforesaid
grooves d, d, and e, e, the same may be formed in the casting, or else they may
bo formed by turning in a lathe, or the larger groove e, e, may be so formed by
turning, or in case of the said grooves being formed in the casting they (or the
larger one e, e,) may be rendered true by turning or by filing in a lathe. The
said
grooves are for the purposo of fastening the several parts of the knob
together, as will be described. Then, in order to prepare brass or other metal
for the exterior surface of the enlarged part of the neck of the knob, a piece of
the same kind of slicet brass or other metal, as was used for making the cup 11,
is to be cut out in a square shape, and that square piece is to be stamped in a
concave die, so so to bring it (by one or more operations of stamping as may
be requisite) to the form 15. Then the exterior border f., f, of that piece of brass,
or other metal 15, is to be clipped true with shears, and a central hole is to
be pierced though it, with a pair of cutting-out tools in the fly press, that hole
being of a proper size to fit tight over the neck part of 14, and then the
piece 15 is to be forced on to the iron casting 14 by pressure of suitable tools

page_text: in. the fly press, so as to make it apply closely thereto. And in order to
prepare brass or other metal for the exterior surface of the small or neck part
of 14, a piece of tubing of brass, or other metal, of a suitable size, to fit on that
neck part, is cut off to the requisite length to form a ferulo 17, which is forced
on around the iron 14 after the picco 15 has been pressed on to the same, as
above stated, the end of the ferule 17 applying against the piece 15 around the
central hole thereof. Note.-The ends of the ferulo 17 must be cut true aud
smooth, but the length of the ferule 17 must be only such as that it will not
extend so far along the neck 14 as the groove d, d, and therefore the ferulo 17
will leave the end of the neck 14 and the said groove d, d, around that end
exposed. Then, in order to form the collar or shoulder 18 around the said end
of the neck 14, the said neck, with the pieco 15 and the ferule 17 upon it, is
to be put into a mould formed of sand, in the usual manner practised by brass-
founders, so as to leave a cavity in that mould around so much of the end of
the iron neck 14 as protrudes beyond the ferulo 17; and melted brass, or
German silver, or other metal, is to be cast around the said protruding end of
the iron 14, and around the groove d, d, thereof, so as to form the collar or
shoulder 18, which by that means becomes firmly fastened around the neck 14.
and therefore the said collar 18 also retains the ferulo 17 and the piece 15 in
place upon the neck 14. The two parts for the knob being thus prepared,
(viz.,) the hollow ball part and the neck part, those two parts are to be put
together by means of a pair of mounting tools, in the same manner as is
commonly practised in manufacturing hollow knobs of brass without iron, that
is to say: The neck is dropt into a hollow tool, which permits the collar 18 to
go down into the hollow of that tool, and a concavity of the said tool above that
hollow affords a resting place for the enlarged part 15 of the neck, and then
the hollow ball C is dropped with its open mouth c, c, over the enlarged part
of the neck, and the part of the ball around the mouth c, c, thereof will also
find a resting place in the said concavity of the said tool, and in that position
of the parts of the border ego c, c, of the said mouth of tho ball C will be
opposite to the groove c, c, around the enlarged part of the neck 14, and then
the prossure of another suitable concave tool upon the convex part of the ball C,
opposite to the mouth thereof; by force of the fly press tho parts surrounding
the open mouth c, c, will bo gathered in moro closely, and that mouth will bo
further contracted, so as to interlock its border edgo c, c, very firmly into the
said groove c, e, as is shewn in the section Y (sco also the outside view =), and
thereby the two parts of the knob become united firmly together, which being
the same mode of union, and being performed with similar tools and in the
same manner as commonly practised in manufacturing hollow knobs of brass

page_text: without iron does not require further explanation. The knob so made as
herein-before described, according to my said improvement, is then finished by
dressing and burnishing the exterior surface in a lathe in the usual manner,
and the collar or shoulder 18 is turned true. And note.-The outer edge or
circumference f.f, of the piece 15, may be burnished down into so much of the
groove e, e, as may remain unoccupied by the border edge c, c,. of the mouth of
the ball C, if desired. Or note.-The said outer edge or circumference of the
piece 15 may, if preferred, have been burnished over into the said groove e, e,
before the neck and the ball were put together, as above described, in which
case the said edge or circumference f.f, of the piece 15, will be included within
the border edge c, c, of the mouth of the ball C. And note.-In case it is
preferred to make the neck of the knob of the shape shewn in section at X,
then the cast-iron for such neck, corresponding to that herein-before described
as 14, is to be cast to the shape shewn in section at a, and the piece of brass
or other metal, corresponding to that herein-before described as 15, may be
stamped to the shape shewn in section at Y, in which case the said piece Y
will cover over the said neck a in the same manner, and so as to effect the.
same purpose in the knob marked X, as the piece 15, together with the
ferule 17, have been herein-described to effect in the knob marked Z; and the
piece Y is to be stamped as many times, in a series of as many successive tools
as may be requisite for bringing it from a flat plate to the said form Y. And
note. The neck part of the knob may be made in the usual manner wholly of
cast brass, instead of being made of thin stamped brass, or other metal, with
cast-iron inside thereof, as herein-before described; but in case of so making.
the neck part wholly of cast brass, then it is only the hollow ball part C of the
knob that will be manufactured according to my improvement, because the
neck part (as well as the mode of putting that neck part and the hollow ball
part together) will, in that case, be according to the common mode of manu-
facturing hollow knobs of brass. The tools employed in the process herein-
before described are of the ordinary kind, and such as are well known, and no
claim of new Invention is made in respect of such tools, nor in the mode of
using the same.
Having now described my said improvement, I, the said Daniel Greenfield,
do hereby declare that the new Invention, whereof the exclusive use is granted
to me by the aforesaid Letters Patent, consists in the improvement herein-
before described, in manufacturing hollow metal knobs for the handles of door
and other locks, the essential character of that improvement being that of
forming an interior lining of stamped iron plate to the hollow ball part of the
knob, and (in case it is preferred) an interior of cast-iron to the neck part of

page_text: the knob, in order, by means of such stamped iron and such cast-iron (if the
latter be used) to give support to the brass, German silver, or other metal,
whereof the exterior surface of such knob is or may be composed.
In witness whereof, I, the said Daniel Greenfield, have hereunto set
my hand and seal, this Seventeenth day of August, One thousand 5
eight hundred and forty-two.