Year: 1886

page_text: I, JOHN WILLIAM GROVER, of No. 9 Victoria Chambers, Westminster in the
County of Middlesex, Engineer, do hereby declare the nature of this invention to
be as follows:-
=
My invention relates to the construction of helical spring washers for bolts and
nuts for which Letters Patent No. 1230 were granted to me on the 3rd April 1873,
wherein a helically coiled rod of steel of rectangular cross section was made to bite
with the edge of its uppermost end against the underside of the nut and with the
edge of its lower end against the fish plate or other surface to be held by the bolt,
whereby the nut was effectually prevented from unscrewing.
According to my present invention, in place of making such helical spring
washers of a rectangular cross section, I make them of a girder section, that is to
say, I make the middle part thereof of a less width than the upper and lower
surfaces. By this means I firstly prevent the rod of steel from losing the parallelism
of its upper and lower surfaces, on being coiled into the helical form, as occurs with
rods of rectangular section as now constructed, and which detracts more or less
from the efficiency of the washer's bite or hold; secondly, I am enabled with the
same or a less quantity of metal to produce a spring washer offering considerably
greater and more uniform resistance to compression to the flattened condition;
thirdly, I can coil the washer more easily, as there is less metal on the inside
surface to compress and less metal on the outside surface to extend; and lastly
I am enabled to effect the tempering of the washer more uniformly throughout the
mass of metal, owing to the thickness thereof being in every part less than that of
the rectangular section and therefore more accessible to the action of the tempering
liquid. The configuration of the cross section of the washer may be greatly varied
in carrying out my invention, but by preference I produce the desired effect by
rolling the rod with a rounded or V-shaped groove on each side thereof.
Dad thin both Inc. of M... TO00
ABEL & IMRAY,
Agents for the Applicant,
28, Southampton Buildings, London, W.C.

page_text: Improvements in Spring Washers for Screw Bolts and Nuts.
I, JOHN WILLIAM GROVER, of No. 9 Victoria Chambers, Westminster in the
County of Middlesex, Engineer, do hereby declare the nature of this invention
and in what manner the same is to be performed to be particularly described and
ascertained in and by the following statement:--
My invention relates to the construction of helical spring washers for bolts and
nuts for which British Letters Patent No. 1230 were granted to the on the
3rd April 1873, wherein a helically coiled rod of steel of rectangular cross section
was made to bite with the edge of its uppermost end against the underside of the
nut and with the edge of its lower end against the fish plate or other surface to be
held by the bolt, whereby the nut was effectually prevented from unscrewing.
According to my present invention, instead of making such helical spring
washers of a rectangular cross section, I make them of a girder section, that is to
say I make the middle part thereof of a less width than the upper and lower
surfaces. By this means I in the first place prevent the rod of steel from losing
the parallelism of its upper and lower surfaces, on being coiled into the helical
form, this distortion, which occurs with rods of rectangular section, detracts more
or less from the efficiency of the washer's bite or hold, secondly I am enabled
with the same or a less quantity of metal to produce a spring washer offering
considerably greater and more uniform resistance to compression tending to flatten
it, thirdly I can coil the washer more easily as there is less metal on the inside
surface to compress and less metal on the outside surface to extend, and lastly,
I am enabled to effect the tempering of the washer more uniformly throughout the
mass of metal, owing to the thickness thereof being in every part less than that of
the rectangular section and therefore more accessible to the action of the tempering
liquid. The configuration of the cross section of the, washer may be greatly varied
in carrying out my invention but by preference I produce the desired effect by
rolling the rod with a rounded or V shaped groove on. each side thereof, as shewn
by the sections Figs. 1 and 2 of the accompanying drawings. Fig. 3 shews the
grooves made of greater depth than at Fig. 1. Fig. 4 shews the grooves of
rectangular forin so as to produce an ordinary girder section. If the grooves bo
made of the same depth on each side of the bar before coiling, then on coiling it to
form the helical washer Fig. 5, the section would assume the shape shewn at Fig. 6,
the groove on the outer side being rendered shallower by the extension of the metal
on that side. This may be prevented by forming the grooves of unequal depth in
the first instance as at Fig. 7, so that on coiling the bar with the deeper groove
outside, this will become reduced in depth and consequently more or less equal to
the groove on the other side.
In some cases I make the spring washers with only the groove on the outer
side.
On comparing the rectangular section Fig. 8 heretofore used for the manufacture
of such spring washers, with those at Figs. 1, 2, 3, 4, 7, it will be readily understood
that with the same or even a less amount of metal, a washer of considerably greater
strength will be obtained and also that the coiling and tempering of the bar will
be more easily effected.

page_text: Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
1. Constructing helical spring washers having a girder shaped section or with the
middle part thereof of a less width than the upper and lower surfaces, substantially
as herein described.
2. The manufacture of blanks for helical spring washers from a bar having
a deeper groove on the one side than on the other, so that on coiling the bar with
the deeper groove on the outer side the extension of the metal tends to make the
outer groove about equal to the inner groove, substantially as herein described with
reference to Fig. 7 of the drawings.