IMPROVEMENTS IN SCREW-BOLTS, NUTS, AND WASHERS, AND IN PROVISIONAL SPECIFICATION, AND IN THE MACHINERY OR APPARATUS FOR MAKING THE SAME
Year: 1852

page_text: LETTERS PATENT to George Walker Nicholson, of Pendleton, in
the County of Lancaster, Tool and Engine Fitter, for the Invention
of "IMPROVEMENTS IN SCREW-BOLTS, NUTS, AND WASHERS, AND IN
PROVISIONAL SPECIFICATION left by the said George Walker
Nicholson at the Office of the 'Commissioners of Patents, with
his Petition, on the 5th October 1852.
I, GEORGE WALKER NICHOLSON, of Pendleton, in the County of Lan-
caster, Tool and Engine Fitter, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN SCREW-BOLTS, NUTS, AND WASHERS,
AND IN THE MACHINERY OR APPARATUS FOR MAKING THE SAME," to be as
follows, and relates,-
Firstly, to a mechanical contrivance for making the bolt and nut
perfectly self-adjusting, so that the bolt will adjust itself to unequal
surfaces without any tendency to be strained, and will have as good a
bearing as if the flanges or surfaces were of uniform thickness.

page_text: Secondly, to the construction of a nut-maundrill perfectly self-
adjusting, so that if the nut be badly or imperfectly forged the washer
will adjust itself to the inequality, and prevent the tendency to strain
the maundrill and injure the thread.
The principle of this Invention will be easily understood by reference
to the accompanying outline sketch or drawing.
Fig. 2, represents two plates or flanges. A, is a common bolt;
B, a common nut; C, a self-adjusting bolt; D, a self-adjusting nut.
These bolts pass through two flanges E, and F, which are thicker at
the roots than the extremities. G, G, are self-adjusting washers.
It is evident that to tighten the bolt A, would strain it, and night
break it, but the bolt C, adjusts itself to the unequal surfaces without
any tendency to be strained, and has as good a bearing as if the
flanges were of uniform thickness. Fig. 1, represents a self-adjusting
nut-maundril. A, is a convex collar. B, is a washer, concave on
one side and flat on the other. C, is a nut, which is screwed. upon
the thread of the maundrill for the purpose of being turned. The
nut is represented as being very badly forged, yet the washer adjusts
itself to the inequality, and thus the tendency to strain the maundrill
and to injure the thread is entirely prevented; the nut may be at once
turned true. The turning of it twice or thrice is unnecessary; but this
is necessary in the case of a very crooked nut being turned on a
common nut-maundril.
I desire it to be distinctly understood that this is merely an outline
description of my said improvements, which I shall more fully and
clearly explain in my Complete Specification.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said George Walker Nicholson in the Great Seal
Patent Office, on the 2nd April 1853.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
GEORGE WALKER NICHOLSON, of Pendleton, in the County of Lan-
caster, Tool and Engine Fitter, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her

page_text: Royal Letters Patent, bearing date the Fifth day of October, in the year
of our Lord One thousand eight hundred and fifty-two, and in the six-
teenth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said George Walker Nicholson, Her especial
license that I, the said George Walker Nicholson, my executors,
administrators, and assigns, or such others as I, the said George
Walker Nicholson, my executors, administrators, and assigns, should
at any time agree with, and no others, from time to time and at all
times thereafter during the term therein expressed, should and lawfully
might make, use, exercise, and vend, within the United Kingdom of
Great Britain and Ireland, the Channel Islands, and Isle of Man, my
Invention of IMPROVEMENTS IN SCREW-BOLTS, NUTS, AND WASHERS, AND
IN THE MACHINERY OR APPARATUS FOR MAKING THE SAME," upon the con-
dition (amongst others) that I, the said George Walker Nicholson,
by an instrument in writing under my hand and seal, should par-
ticularly describe and ascertain the nature of the said Invention, and
in what manner the same was to be performed, and cause the same to
be filed in the Great Seal Patent Office within six calendar months
next immediately after the date of the said Letters Patent, as reference
being thereunto had will more fully and at large appear.
NOW KNOW YE, that I, the said George Walker Nicholson, do
hereby declare the nature of my said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained
in and by the following statement, that is to say:
My Invention relates, firstly, to an improved method of rendering
screw-bolts, nuts, and washers self-adjusting, so that though the object
grasped between the head of the bolt and the surface of the nut be not
of uniform thickness, the strain on the bolt shall be equally distributed
over the whole area thereof; which I effect by making the surface of the
nut and the under side of the head of the bolt convex, and by making
the washers, which I use under the nut and under the head of the bolt,
concave, to correspond with the convexity of the nut and of the bolt
head. Secondly, to an improved method of rendering a nut-mandril,
that is, a mandril on which nuts are turned, self-adjusting, so that
though the surface of the nut be not true, that is, not at right angles

page_text: with the axis of the nut, the strain on the nut-mandril shall be equally
distributed over the whole area thereof, which I effect by. forming a
convex collar on the nut mandril, and by using a concave washer to
correspond therewith, so that if the nut be. badly or imperfectly forged
the washer will adjust itself to the inequality, and prevent the tendency
to strain the mandril and injure. the thread; and, thirdly, to an
improved method of -turning-a-convex nut,-which I-effect--by using a
concavo-concave washer along with the self-adjusting nut-mandril..
The nature and principle of these my improvements will be more
clearly understood by reference to the annexed Sheet of Drawings, on
which the same letters of reference are used to represent similar part
or parts where different views or diagrams are shown.
- Fig. 1, represents a view of the self-adjusting nut-mandril with the
concave washer upon it, and an untrue nut is screwed upon the thread,
which illustrates the self-adjusting principle of the mandril. Fig. 2,
represents two flanges connected by a self-adjusting bolt, nuts, and
washers. The flanges are thicker at the insertion than 'at-the circum-
ference, yet without the slightest tendency to be unequally strained the
bolt, nut, and washers have as good a bearing as if the flanges were of
uniform thickness. A common bolt is also passed through the flanges
to illustrate its unfitness to grasp a taper object. Fig. 3, an elevation
of- a self-adjusting bolt and nut. Fig. 4, a view of the double concave
washer; and Fig. 5, a plan of the same. A, is the self-adjusting nut-
mandril; B, the convex collar; C, the concave washer; D, the
untrue nut screwed upon the nut-mandril; E, the bevilled flanges;
F, the self-adjusting bolt; G, the self-adjusting nut; H, the self-adjust-
ing washers; I, the common bolt; K, the common nut; and L, the
double concave washer.
Having thus explained the nature and principle of my Invention, I
desire it to be distinctly understood that I do not confine myself to the
exact details herein described, as the same may be varied or modified
without departing from the principle thereof. But what I claim as new
and of my Invention is. Firstly, an improved method of rendering screw-
bolts, nuts, and washers self-adjusting, so as to grasp objects the surfaces
of which are not at right angles with the axes of the bolts. Secondly,

page_text: an improved method of rendering a nut-mandril self-adjusting, so that
if the surface of the nut to be turned thereon be not at right angles
with its axis, the strain on the area of the mandril shall be equally
distributed over every part thereof. Thirdly, an improved method of
turning a convex nut, as all of the said improvements are herein
described and illustrated.
In witness whereof, I, the said George Walker Nicholson, have
hereunto set my hand and seal, this First day of April, One
thousand night hundred and fat.
GEORGE WALKER NICHOLSON. (L.s.)
Signed, sealed, and delivered by the
said George Walker Nicholson
in the presence of
E. J. HUGHES,
Patent Agent,
Manchester.