Year: 1899

page_text: Date of Application, 13th June, 1899
Complete Specification Left, 13th Mar., 1900-Accepted, 14th Apr., 1900
I, FREDERICK JOHN TALBOT, of Globe Steel Works, Sheffield, in the County
of York, Chairman of Ibbotson Brothers and Company Limited, do hereby
declare the nature of this invention to be as follows:-
In constructing my improved lock nut I form a nut blank with a hole of an
internal diameter somewhat smaller than that required for Whitworth's standard
thread, and I form slits or saw-cuts in the outer end of the said nut blank;
I then expand the slit or sawn end of the said nut blank.
Whilst the end of the said nut blank is expanded, I drill a parallel hole com-
pletely through the same, and I tap the hole thus made with a Whitworth
standard tap. I then release the slit or sawn end of the nut so that the outside
of the slit or sawn end of the nut may resume its former position. It will then
be found that the hole in the outer end of the nut is somewhat cone shaped, the
internal diameter being smaller at the outer end than at the other end of the nut,
so that when a bolt which fits the solid end of the nut is inserted in the latter
the threads at the slit or sawn end thereof will grip the threads of the bolt so
firmly that the nut will be securely locked upon the bolt.
It follows from the process of manufacture herein described, that the sawn
edges of the nut will not come into such close contact with the threads on the
bolt as the centre portion of each segment of the nut; consequently there will
be no cutting action or injury to the threads.
Furthermore, as the outside of the nut is not pressed inwards to cause the
threads of the nut to grip the threads of the bolt, there will be no tendency of
the spanner to slip off the end of the nut. In fact, as the action of screwing up
will tend to enlarge the outer end of the nut, the effect will be to prevent any
slipping of the spanner.
I may employ only one slit or saw cut in the nut in which case the hole in
the finished nut (when treated as herein before described) instead of being "cone
shaped" at the sawn end, will be of a gradually reduced size and somewhat of the
shape of one coil of a volute.
Although I have described a nut having a Whitworth's standard thread, any
description of thread may be used, for if the end of the nut is held expanded
during the process of tapping, the after effect will be the same.
Dated this 18th day of June 1899
HARRIS & MILLS,
23, Southampton Buildings, London, W.C., Agents.

page_text: •
I, FREDERICK JOIN TALBOT, of Globe Steel Works, Sheffield, in the County
of York, Chairman of Ibbotson Brothers and Company Limited, 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: --
I will describe my invention by the aid of the accompanying drawings in which
Figs. 1 and 2 represent respectively an end view and a longitudinal section of a
square nut having four slits or cuts made from a blank having a hole some-
what smaller than that required for Whitworth's standard thread, said views
showing the nut in its expanded state during process of manufacture. Figs. 3
and 4 represent the same nut when finished and removed from the tools. Figs. 5
to 8 represent similar views of a hexagonal nut and Figs. 9 to 12 represent
similar views of a square nut made according to my invention but having only
one slit or cut and Fig. 13 is a side view of said nut when finished and removed
from the tools.
In constructing my improved lock nut whether square or hexagonal I form a
nut blank in the ordinary manner with a hole of a diameter somewhat smaller
than that required for Whitworth's standard thread, and I form slits or saw cuts a
in the outer end a¹ of said nut blank; I then expand the slit or sawn end of the
said nut blank when the outer end a¹ will assume the shape or position shown by
full lines in Figs. 1, 2, and 5, 6, the normal size or inner end of the nut being
shown by dotted lines in Figs. 1-5.
Whilst the outer end of the said uut blank is thus expanded I drill a parallel
cylindrical hole completely through the same and I tap the hole thus made with
a Whitworth standard tap, I then release the slit or sawn end a¹ of the nut so that
the outside of the slit or sawn end of the nut may as shown at Figs. 3, 4, 7, 8
resume its former position. It will then be found that the hole in the outer end a¹
of the nut is somewhat cone shaped, the diameter of the threads being smaller
at the outer end a than at the other end of the.nut, so that when a bolt which
fits the solid end of the nut is inserted in the latter the threads at the slit or
sawn end a thereof will grip the threads of the bolt so firmly that the nut will
be securely locked upon the bolt.
It follows from the process of manufacture herein described, that the slit or sawn
edges of the part of the nut will not come into such close contact with the
threads of the bolt as the centre portion of each segment of such part of the nut,
consequently there will be no cutting action or injury to the threads of the nut
or bolt.
Furthermore as the outside of the part a¹ of the nut is not pressed inwards to
cause the threads of the nut to grip the threads of the bolt, there will be no
tendency of the spanner to slip off the outer end a¹ of the nut. In fact as the
action of screwing up will tend to enlarge the outer end a¹ of the nut, the effect
will be to prevent any slipping of the spanner.
As represented at Figs. 9 to 12 I may employ only one preferably inclined slit
or saw cut in the nut but otherwise proceed in its manufacture in a similar
manner to that described with respect to the nuts represented at Figs. 1 to 8.
When the uut represented at Figs. 9 to 12 is finished the hole in the part a¹
instead of being cone shaped; will be of a gradually reduced size and somewhat of
the shape of one coil of a volute.
Although I have described a nut having a Whitworth standard thread, any

page_text: description of thread may be used, for if the end of the nut is held expanded
during the process of tapping, the after effect will be the same.
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. A nut having the following characteristics, viz.: an inner end having an
ordinary tapped cylindrical hole, an outer end divided by one or more slits or saw
cuts and having a tapped hole forming a conical or gradually contracted continua-
tion of the tapped hole in the inner end of the nut and an exterior, the sides of
which are in the same plane in both parts of the nut, substantially as herein
set forth.
2. A nut having the characteristics claimed in Claim 1 and made by the
following processes, viz.: 1st making a nut blank in the usual way with a hole
somewhat smaller than that required for the ordinary tapped hole, 2nd dividing
the outer end of the nut blank by one or more slits or saw cuts, 3rd expanding
the divided outer end of the nut blank, 4th drilling a parallel hole completely
through the nut blank whilst the outer end is so expanded, 5th tapping said hole
and 6th releasing the slit or sawn end of the nut, substantially as herein set forth.
Dated this Sth day of March 1900.
HARRIS & MILLS,
23, Southampton Buildings, London, W.C., Agents.
HARRIS & MILLS,
23, Southampton Buildings, London, W.C., Agents.