IMPROVEMENTS IN SCREW BOLTS AND NUTS
Year: 1872

page_text: LETTERS PATENT to John Arthur, of Sandy Croft, Hawarden, in the
County of Flint, Engincer, for the Invention of "IMPROVEMENTS IN
SCREW BOLTS AND NUTS."
Scaled the 20th December 1872, and dated the 22nd June 1872.
PROVISIONAL SPECIFICATION left by the said John Arthur at the
Office of the Commissioners of Patents, with his Petition, on the
22nd June 1872.
I, JOHN ARTHUR, of Sandy Croft, Hawarden, in the County of Flint,
Engineer, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN SCREW BOLTS AND NUTS," to be as follows:-
This Invention relates to improvements in the construction of screw
bolts and nuts, whereby they are prevented from unscrewing and
becoming loose when placed in horizontal or inclined positions and
exposed to vibration arising from the motion of machinery or the parts
to which they are applied.

page_text: My improvements are particularly applicable to the screw bolts and
nuts employed for bolting the fish plates to the ends of railway rails as
they are very liable to become loose and detached.
According to my Invention I form the heads of screw bolts with an
enlargement or elongation on one side thereof (or I apply a weight 5
thereto) in order that when the stem of the bolt is in its place the
weighted side of the head will by its own gravity prevent it from
turning.
The screw nuts are caused to act in like manner by forming them
oblong or with an enlargement on one side, the hole for the male screw 1
being placed nearer to one end than the other, thus causing the heaviest
side by its own gravity to fall downwards and thus prevent it from
turning when exposed to vibration.
The jaws of the spanner or wrench employed for screwing or
unscrewing oblong nuts of this character arc by preference formed wider 1
at the mouth than at the bottom of the opening so as to fit the oblong
nut cither longitudinally or transversely.
In applying my improvements to the bolts and nuts employed for
securing fish plates I prefer to support the ends of the rails upon a
shallow chair or support, by which arrangement much of the vibration 20
is prevented, and I also prefer to employ double-threaded screws for this
and similar purposes where they are exposed to great vibration.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Arthur in the Great Seal Patent Office on the
21st December 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
ARTHUR, of Sandy Croft, Hawarden, in the County of Flint, Engineer,
send greeting.
25
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-second day of June, in the year 30
of our Lord One thousand eight hundred and seventy-two, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said John Arthur, Her special license that

page_text: I, the said John Arthur, my executors, administrators, and assigns, or
such others as I, the said John Arthur, 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, an Invention for "IMPROVEMENTS IN SCREW BOLTS AND
NUTS," upon the condition (amongst others) that I, the said John Arthur,
my executors or administrators, by an instrument in writing under my,
or their, or one of their hands and seals, should particularly 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 and imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said John Arthur, do hereby declare the
nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say :-
This Invention relates to improvements in the construction of screw
bolts and nuts, whereby they are prevented from unscrewing and
becoming loose when placed in horizontal or inclined positions and
exposed to vibration arising from the motion of machinery or the parts
to which they are applied.
My improvements are particularly applicable to the screw bolts and
nuts employed for bolting the fish plates to the ends of railway rails as
they are very liable to become loose and detached.
And in order that my Invention may be clearly understood and readily
carried into practice, I will proceed to describe the same, reference
being made to the Drawing hereunto annexed, which shows several
views of bolts and nuts constructed in accordance with my Invention,
and also as applied for securing the fish plates of railway rails.
According to my Invention the heads of the screw bolts a are formed
with an enlargement or elongation at a¹ on one side thereof, as shown in
the Drawing (or I apply a weight thereto if preferred), in order that
when the stem of the bolt is in its place the weighted side of the head
will by its own gravity prevent it from turning and thus becoming
loose.

page_text: The screw nuts 6 are caused to act in like manner by forming them
oblong or with an enlargement 6¹ on one side, the hole for the male screw
being placed nearer to one end than the other, thus causing the heaviest
side by its own gravity to fall downwards and thus prevent it from
turning.
The jaws of the spanner or wrench c employed for screwing or
unscrewing oblong nuts of this character are by preference formed wider
at the mouth c¹ than at the bottom of the opening, as shown in
the Drawing, so as to fit the oblong nut either longitudinally or trans-
versely.
In applying my improvements to the bolts and nuts employed for
securing fish plates I prefer to support the ends of the rails upon a
shallow chair or support, by which arrangement much of the vibration
is prevented, and I also prefer to employ double-threaded screws for
this and similar purposes where they are exposed to great vibration.
Having thus described the nature of my Invention, and the manner
of performing or carrying the same into practice, I would have it under-
stood that I do not confine myself to the exact details herein described
and shown, as the same may be varied without departing from the truc
character of my Invention; but what I claim is the improved construc-
tion of screw bolts and nuts with an elongation, enlargement, or weight
on one side so as to prevent them from unscrewing or becoming loose
from vibration, substantially as herein-before described and shown in the
Drawing hereunto annexed.
In witness whereof, I, the said John Arthur, have hereunto set
my hand and seal, this Eighteenth day of December, in the year