IMPROVEMENTS IN WASHERS FOR SCREW BOLTS
Year: 1873

page_text: LETTERS PATENT to John William Grover, of No. 9, Victoria Cham-
bers, Westminster, in the County of Middlesex, for the Invention
of "IMPROVEMENTS IN WASHERS FOR SCREW BOLTS."
PROVISIONAL SPECIFICATION left by the said John William Grover at
the Office of the Commissioners of Patents, with his Petition, on
the 3rd April 1878.
I, JOHN WILLIAM GROVER, of No. 9, Victoria Chambers, Westminster,
in the County of Middlesex, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN WASHERS FOR SCREW BOLTS," to be as
follows:-
My Invention consists in constructing washers of metal rings, by
preference of tempered steel, which washers are cut completely through
at one point, each of the two severed portions being respectively deflected
or bent in opposite directions from the plane of the washer. Each severed
portion forms a sharp cutting edge which, on the nut being screwed up,
bears hard respectively against the base or fish plate, and against the

page_text: under surface of the nut, while the washer formed as above constitutes
a spring which, as the nut is screwed up, is compressed, and thus causes
the projecting edges to press with increasing forco. The said cut ends
are turned up in the contrary direction to that of the thread of the bolt
on which the washer is to be employed, so that the washer will permit
of the screwing up of the nut, but will resist its unscrewing by means of
the said edges tending to bite into the surfaces of the nut and the
base.
The cut of the washer may be made square to its face, but by pre-
ference I make the cut in a slanting direction, so as to form a somewhat
acute angle on the cutting edges; or I produce an acute angle by
hollowing out the severed faces of the washer.
When the cut is formed at an angle I sometimes close up the opening
of the cut by pressing the two ends together, in order that when the
washer has been compressed somewhat by the nut the sloping surfaces
may press upon each other, and thereby offer increased resistance to the
further compression of the washer, inasmuch as when it is compressed
beyond this point the action of the sloping surfaces would cause the
washer to be expanded in the direction of its plane; or, in place of
closing up the cut as described, I insert a thin piece of steel into the
cut, which will have the same effect.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John William Grover in the Great Seal Patent
Office on the 18th September 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN 2
WILLIAM GROVER, of No. 9, Victoria Chambers, Westminster, in the
County of Middlesex, send greeting.
year
of our
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Third day of April, in the
Lord One thousand eight hundred and seventy-three, in the thirty-sixth 3
year
of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said John William Grover, Her special license that
I, the said John William Grover, my executors, administrators, and

page_text: assigns, or such others as I, the said John William Grover, 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 WASHERS
FOR SCREW BOLTS," upon the condition (amongst others) that I, the said
John William Grover, 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 immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said John William Grover, 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, reference being had to the accom-
panying Sheet of Drawings, and to the figures and letters marked
thereon, that is to say :-
My Invention consists in constructing washers of metal rings, by
preference of tempered steel, which washers are cut completely through
at one point, cach of the two severed portions being respectively deflected
or bent in opposite directions from the plane of the washer. Each
severed portion forms a sharp cutting edge which, on the nut being
6 screwed up, bears hard respectively against the base or fish plate, and
against the under surface of the nut, while the washer formed as above
constitutes a spring which, as the nut is screwed up, is compressed, and
thus causes the projecting edges to press with increasing force. Tho said
cut ends aro turned up in the contrary direction to that of the thread of
the bolt on which the washer is to be employed, so that the washer will
permit of the screwing up of the nut, but will resist its unscrewing by
means of the said edges tending to bite into the surfaces of the nut and
the base.
The cut of the washer may be made square to its face, but by pre-
5 ference I make the cut in a slanting direction so as to form a somewhat
acute angle on the cutting edges; or I produce an acute angle by
hollowing out the severed faces of the washer.

page_text: When the cut is formed at an angle I sometimes close up the opening
of the cut by pressing the two ends together, in order that when the
washer has been compressed somewhat by the nut the sloping surfaces
may press upon each other and thereby offer increased resistance to the
further compression of the washer, inasmuch as when it is compressed
beyond this point the action of the sloping surfaces would cause the
washer to be expanded in the direction of its plano; or, in place of
closing up the cut as described, I insert a thin piece of steel into the cut,
which will have the same effect.
Figs. 1 and 2 shew respectively a side view and a plan of the improved
washer. The washer A is divided at X by a cut, which is preferably
inclined, and the parts a, a¹ on each side of the cut are bent a little in
opposite directions, so as to prevent edges a³, a³, like those of a tool used
for turning or planing metals.
Fig. 3 shews a side view of the washer applied to a bolt B and nut B¹
in its condition before the nut is screwed up, from which it will be seen
that the bent parts of the washer A are inclined in a direction opposite
to that of the screw thread on the bolt B, so that they permit the nut to
be screwed home without resistance.
1
2
Fig. 4 shews the nut B' screwed home so as to compress the washer
between it and the base, fish plate, or other object C to which the bolt,
nut, and washer are applied. In attempting to turn the nut back so as
to unscrew it the spring of the washer causes the edges a³ and a* to bite
into the under side of the nut B¹ and upper surface of the base C, thus a
offering a great resistance to the unscrewing of the nut.
In cutting the washer at X there will be enough clearance to permit
the washer to be quite flattened, as shewn in Fig. 4; but even if the
edges of a sloping cut come close together, as shewn in Fig. 5, the
washer could be flattened down by the nut giving out laterally, as a
indicated by the dotted lines in Fig. 6, and by springing in again when
relieved of downward pressure, tending to raise the edges of the cut so
as to make them bite as above described.
The washers may be made of round metal, as shewn in Figs. 7 and 8;
they may also, instead of being circular, be made square or polygonal, a
as may be readily understood.

page_text: A convenient mode of manufacturing the improved washers is to coil
a rod of soft steel helically on a mandril, as shewn in Fig. 9, and then
to make a saw cut a, a, throughout the length of the helix A, so that
each of its coils can be removed from the mandril as a separate washer
(as shewn at Fig. 10), and hardened and tempered.
Having thus described the nature of my Invention, and in what
manner the same is to be performed, I claim, the use of spring washers
so divided by a single cut across one part of their periphery, and bent on
each side of the cut as to present cutting edges to resist the unscrewing
of the nuts to which they are applied, substantially as herein described.
In witness whereof, I, the said John William Grover, have hereunto
set my hand and seal, this Twenty-third day of July, in the year
of our Lord One thousand eight hundred and seventy-three.