CERTAIN IMPROVEMENTS IN MACHINERY OR APPA- RATUS FOR CUTTING SCREWS
Year: 1852

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN.
RAMSDEN, of Ardwick, in the County of Lancaster, Screw Bolt Manufacturer,
send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Sixth day of July, One thousand eight hundred and fifty-two, in
the fifteenth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said John Ramsden, Her especial licence, full
power, sole privilége and authority, that I, the said John Ramsden, my
exors, adiñors, and assigns, and such others as I, the said John Ramsden,
my exors, admors, or assigns, . at any time agree with, and at all times
during the term of years therein expressed, should, and lawfully might make,
use, exercise, and vend, within England, Wales, and the Town of Berwick-
upon-Tweed, my Invention of "CERTAIN IMPROVEMENTS IN MACHINERY OR APPA-
RATUS FOR CUTTING SCREWS;" in which said Letters Patent is contained a
proviso that I, the said John Ramsden, shall cause a particular description of
the nature of my said Invention, and in what manner the same is to be
performed, to be enrolled in Her Majesty's High Court of Chancery within
six calendar months next and immediately after the date of the said in part
recited 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, I, .the said
John Ramsden; do hereby declare that the nature of the said Invention; and

page_text: the manner in which the same is to be performed, is particularly described
and ascertained in and by the Drawings hereto annexed, and the following
explanation thereof, that is to say:-
My improvements in machinery or apparatus for cutting screws apply solely
to machinery or apparatus to be employed in place of the ordinary dies or
chasing tools for the purpose of cutting or forming the screw or thread.
My improved apparatus differs principally from that hitherto in use in the
form of the tool or cutter, the cutting surface of which is brought to a point,
and is capable of cutting in either direction, either backwards or forwards.
The principal objects or advantages to be obtained by the employment of my
Invention are,-
First, it combines the expedition of the die with the truth or accuracy of
the chaser.
Secondly, the thread is absolutely cut of the metal, without raising or
drawing the thread out of truth, whereas the die raises the thread, making
that part of the screw of a larger diameter than the uncut part of the
same.
.
Thirdly, with my improved apparatus, we are only confined to the pitch or
speed of the cutter (which can be changed as readily as a die), but with the
same cutter can cut any diameter of screw from one eighth of an inch up to
twelve inches, provided that the hole in the centre of the machine is suffi-
ciently large whilst a die of the ordinary.construction formed for cutting half-
inch pins or bolts will not cut either seven sixteenths or nine sixteenths.
Fourthly, my improved cutter being a pointed tool, is capable of being
ground upon a stone in the same way as other cutting tools; it is not liable
to be heated by friction like the die, and when out of order is much more
readily restored or replaced than the die, will wear longer, and in cutting
large diameters requires considerably less power than the die. And,
Fifthly, as my improved. cutter holds, cuts, and gives the speed of the
thread itself, it is not liable to the same objection as the screw-cutting lathe,
in which the vibration or "back lash" (as it is termed) of the traverse
screw and pinion occasion a certain amount of untruth.
Such being the nature and object of my said improvements, I will proceed
to shew their practical application, and in order to facilitate the description
of the same; I have attached to these Presents a Sheet of Drawings illus-
'trating the adaptation to my Invention of hand-screwing stocks.
.
Fig. 1 represents a face view of my improved apparatus complete, and
Fig. 2 an edge view of the same. Fig: 3 is a face view with. the slides, &c.
removed. Fig. 4 is a section taken through the line A, B, and Fig. 5. is a

page_text: similar view taken through the line C, D. a, a, is an outer case or box to
which the handles or levers b, b, are attached, by means of which manual
power or leverage is applied to work the apparatus.
c, c, c, c, are four
sliding blocks for holding the four cutters d, d, d, d; and e, e, e, e, are four
slides for steadying the said blocks. ff.ff, are four screws formed with
pointed ends to prevent vibration and working through the blocks c, c, c, c.
9, 9, 9, 9, are four bevil pinions keyed upon the screws f; f, f, f, and connected
or geared together by means of the bevil wheel h, h, at the back. It will be
observed that one of the screws f extends through the outer casing or box
a, a, and the end thereof is formed square so as to allow of its being turned
by means of a key or otherwise. The blocks c, c, c, c, are formed with
bevilled or V-shaped edges, and the slides e, e, e, e, are formed in a similar
manner, in order to keep the blocks c, c, c, c, in their respective places as the
blocks or the slides wear, or they may be tightened up by turning the screws
i, i, i, i; and the screws f,ff.f, may be also tightened up by turning the
screws k, k, k, k. 1, 1, 1, 1, are set screws for holding the cutters d, d, d, d, firm
in the blocks c, c, c, c; and m, m, m, m, are four shields or clearers for prevent-
ing the cutting from choking the screws or slides. It is evident that the
cutters may be removed and replaced at pleasure upon slackening the set
screws, and that they may be accommodated to the diameter of the pin bolt
or blank to be cut or screwed by turning the screw f¹.
I would here remark, that although I have described my improved appa-
ratus as having four cutters, yet I do not intend to confine myself to the use
of that precise number, although for general work I find it the most advan-
tageous; for some kinds of work also I find it best to have the cutters with
double points, that is to say, similar to a Winstead of a V, but in that case
they will only cut the particular diameter of pin for which they are originally
adapted; the cutters also may be advanced by a variety of other contrivances in:
place of the bevil gear and screws, but the arrangement exibited in the Draw-
ings is the one which I prefer. I have shewn my Invention in the Drawing,
and described it above as applied to hand stocks, the method of using which
it is needless to describe here, being so well known. When a machine for
the bench is desired, two uprights or standards must be substituted for the
levers b, b, and the pin to be screwed is to be placed in a sliding socket and
turned by means of a winch handle, the cutter itself giving the speed. When
it is desired to adapt my apparatus to steam power, two eyes must be sub-
stituted in place of the said levers, at a sufficient distance apart to work upon
the slide rods of a screw-cutting lathe, the shaft to be screwed revolving and
the cutting apparatus sliding.

page_text: Having thus described the nature, and object of my said improvements,
together with the manner of carrying the same into practical effect;. I would
remark in conclusion, that I claim as my Invention the peculiar form of
cutter for manufacturing screws and screw bolts, as shewn in the Drawing
and above described, without reference to the mechanism to be employed för
advancing and retreating the same, or whether the same may be adapted to
hand, steam, or other power.
In witness whereof, I, the said John Ramsden, have hereunto set my
hand and seal, this Fourth day of January, in the year of our Lord'
One thousand eight hundred and fifty-three.
Enrolled the Fifth day of January, in the year of our Lord One thousand
eight hundred and fifty-three.