Year: 1886

page_text: Date of Application, 8th Sept., 1886
Complete Left, 8th July, 1887
Complete Accepted, 30th Aug., 1887
I, ALFRED BUCKINGHAM IBBOTSON, of Ibbotson, Brothers & Co., Globe Steel Works,
Sheffield in the County of York, do hereby declare the nature of this invention to
be as follows:-
My invention relates to lock-nuts for screw bolts chiefly designed for securing
railway rails at their joints or in or on their chairs or sleepers.
In the Specifications of former Letters Patent viz. No. 1508 dated 18th April 1877
and No. 5082 dated 11th December 1878 I have described a mode of making a screw
nut which without the use of separate or additional parts or devices for locking or
fastening it will have a secure and permanent grip or hold upon the bolt to which it is
applied, this object being accomplished by making some of the screw threads in the
nut of such a diameter that they cannot, without the exertion of much greater force
than can be employed by the fingers alone, be screwed home upon the bolt. These
nuts are now generally known as "Ibbotson lock-nuts."
The object of my present invention is to provide the means for forming the small
threads of such nuts in a more accurate and less costly manner than has hitherto been
practicable.
I am aware that it has been already proposed to make lock-nuts with one part
reduced in diameter by compression applied after the nut has been tapped in the
ordinary manner, but the method adopted of reducing the diameter of the threads will
not ensure the result which is the object of my invention, as it provides no means for
effectually compressing the nut without distorting or altering its threads.
In the manufacture of my lock-nuts, I first tap the same in the ordinary manner,
that is to say, I form in them a parallel screw-thread adapted to fit properly the bolts
with which the said nuts are to be used. I then complete the manufacture of the
said nuts to adapt them for the purpose of my invention in the following manner, I
use apparatus comprising a mandrel which is preferably formed of steel and hardened
and which is tapered in diameter at one end and has cut thereon screw-threads which
are an exact counterpart of the reduced threads to be formed in the nut. This

page_text: mandrel, therefore, serves not only as a tool for finishing the small screw threads in
the nuts, but also as a gauge which, in the manufacture of any number of such nuts,
will ensure the making of the threads in all of them accurately to one uniform size.
In combination with the said mandrel, I use a receptacle for holding the nuts so that
they cannot turn with the screw-threaded mandrel during the insertion of the same.
This receptacle or holder is formed with a hole or space large enough in diameter to
permit the end of the mandrel to enter it. The nut, preferably after being heated, is
placed in the said holder, and the said space then forms a continuation of the hole of
the nut so that the end or point of the mandrel can pass clear through the nut. The
length or depth of this space is regulated so that its inner end serves as a stop for
the mandrel, or I provide other devices for stopping the said mandrel when the end of
the same has been forced through the nut the exact distance required to bring its taper
threads into the proper position relatively to the nut. Then, while the mandrel is in
this position, by the application of pressure to the outside of the nut, the part of the
same in which the threads are to be reduced in diameter is closed in and around upon
the taper portion of the mandrel, so that the screw-threads in such part or end of the
nut are forced into the taper or small threads of the mandrel and receive therefrom
the exact configuration required. 1 prefer that the pressure should be so applied as
to simultaneously compress the sides and corners of the nut. The outer end of the
mandrel is made to serve as a handle by which it can be conveniently held and
manipulated to facilitate the compression of the nut.
In the Specification of former Letters Patent No. 5082 A.D. 1878, I have described
nuts which have grooves or slits formed across and partly through them and having
cutting edges. The nuts made according to my present invention are not necessarily
formed with such grooves or slits, but in some instances, it will be advantageous to so
form them. The slits or grooves are made through the part of the nut which contains
the reduced or taper threads, but the slitting or grooving is of such a character that
while facilitating the application of the nut to its bolt it will not alter the screw threads
which have been formed by the mandrel in such manner as to impair their efficiency
in holding the nut upon the bolt.
My present invention affords the means for very advantageously supplying the
"Ibbotson lock nuts" for use with the improved bolts described in the specification
of my patent dated August 13th 1886 No. 10402.
Dated this 8th day of September 1886.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London,
Agents for the Applicant.

page_text: I, ALFRED BUCKINGHAM IBBOTSON, of Ibbotson, Brothers & Co., Limited, Globe
Steel Works, Sheffield, in the County of York, 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 lock-nuts for screw-bolts, chiefly designed for securing
railway-rails at their joints or in or on their chairs or sleepers.
In the Specification of former Letters Patent, viz No. 1508 dated 18th April 1877,
and No. 5082 dated 11th December 1878, a screw-nut is described which has its
threads so formed that, without the use of separate or additional locking or fastening
devices, it will have a secure and permanent grip or hold upon the bolt to which it is
applied, this object being accomplished by making some of the screw-threads in the
nut of such a diameter that they cannot, without the exertion of much greater force
than can be applied by the fingers alone, be screwed home upon the bolt. These nuts
are now generally known as "Ibbotson lock-nut."
The object of my present invention is to provide the means for forming the small or
reduced threads of such nuts in a more accurate and less costly manner than has
hitherto been practicable.
I am aware that it has been already proposed to make lock-nuts with the threads in
one part thereof reduced in diameter by compression applied after the nut has been
tapped in the ordinary manner; but the method adopted of reducing the diameter of
the threads will not ensure the result the attainment of which is the object of my
invention, as it does not provide for effectually compressing the nut without distorting
its threads or altering the same in respect of their pitch, depth or width.
In the manufacture of a lock-nut according to my present invention, I first tap a
nut in the ordinary manner, that is to say, 1 form therein parallel screw-threads
adapted to properly fit the bolt with which the said nut is to be used. I then complete
the manufacture of the said nut to adapt it for the purpose of my invention by placing
the said nut upon a taper screw-threaded mandrel and compressing one end of the
said nut by pressure or by impact, as hereinafter more particularly described.
In the accompanying drawings
Figure 1 is sectional elevation showing a taper mandrel and a nut placed thereon,
the said nut being provided with ordinary or parallel screw-threads.
Figure 2 is a similar view showing the said nut compressed at one end thereof.
The remaining Figures of the drawings are hereinafter referred to.
Like letters indicate corresponding parts throughout the drawings.
a is the nut, and b is the screw-threaded mandrel, which is preferably formed of
steel and hardened, and the end 6' of which is tapered or reduced in diameter so
that the threads thereon are an exact counterpart of the reduced threads to be formed
thereby in the nut.

page_text: In combination with the said mandrel, I use a receptacle for holding the nuts so
that they cannot turn with the screw-threaded mandrel during the insertion of the
same. For instance, I use a receptacle or holder c as shown in front elevation and in
transverse section in Figures 3 and 4, or in Figures 11 and 12. This receptacle or
holder is formed with a hole or cavity c¹ large enough to permit the end of the
mandrel to enter it. The nut, preferably after being heated, is placed in the said
holder. The mandrel is then screwed into the nut until the end or point of the said
mandrel passes clear through the said nut into the said hole or cavity c¹, which is
made of such length or depth that its inner end will serve as a stop for the mandrel,
so that the taper or reduced threads on the mandrel may be readily caused to occupy
their proper position within the parallel threads in that part of the nut which it is
desired shall be compressed. Then, after removing the nut from the holder and while
the mandrel is in this position relatively to the ordinary parallel threads of the said
nut, by the application of pressure to the outside of the nut, the part of the same in
which the threads are to be reduced in diameter is closed in around and upon the
taper portion of the mandrel; the screw-threads in such part or end of the nut are
thus forced into the taper or small threads of the mandrel and receive therefrom the
exact configuration required, as shown in Figure 2. 1 prefer that the pressure should
be so applied as to simultaneously compress the sides and corners or angles of the nut.
For this purpose, I use pressing dies or swages such as those shown at d, d¹, in
Figures 5 and 6, which are front elevations showing respectively dies or swages for
square and hexagonal nuts.
It is obvious, however, that I may use other suitable devices for effecting the
compression of one end of the nut while the same is held upon the taper screw-threaded
mandrel as above described.
The outer end of the mandrel b is made to serve as a handle by which the nut, when
screwed upon the inner end thereof, can be conveniently held and manipulated to
facilitate its compression.
The mandrel 6 serves not only as a tool for finishing the small screw-threads in the
nuts, but also as a gauage, which, in the manufacture of any number of such nuts, will
ensure the making of the threads in all of them accurately to one uniform size.
I sometimes provide other means than those above described for stopping the said
mandrel when the end of the same has beon forced through the nut the exact distance
required to bring its taper threads into the proper position relatively to the nut as
illustrated in Figure 1. For instance, I make the mandrel with a shoulder b
(Figure 10), which, when the mandrel has been screwed the required distance through
the nut, will come in contact with the face of the said nut. The length or depth of
the hole or cavity c¹ in the holder c need not, in this case, be limited as above
described.
In the said former Specification No. 5082, are described nuts which have grooves or
slits formed across and partly through them and having cutting edges. The nuts made
according to my present invention are not necessarily formed with such grooves or
slits; in some instances, however, it will be advantageous to so form them. The slits
or grooves are made through the part of the nut which contains, or is intended to
contain the reduced or taper threads; the slitting or grooving is, however, of such a
character that, while facilitating the application of the nut to its bolt, it will not alter
the screw-threads, which have been, or will thereafter be, formed by the mandrel, in
such a manner as to impair their efficiency in holding the nut upon the bolt.
In practice, I find it more advantageous to form the slits in the nut before it is
tapped, or before the compression of any of the parallel threads, as I am thus enabled
to compress those portions of the threads requiring compression while the nut is at a
very low head, and, in some instances, the compression can be effected without any
heating of the nut.
Figure 7 is a plan, and
Figure 8 is a side elevation of a nut formed with the said slits or grooves, and

page_text: My present invention affords the means for very advantageously making Ibbotson
lock-nuts adapted for use with the improved bolts described in the Specification of
Letters Patent granted to me and dated August 13th 1886, No. 10402.
It is evident that I can, if desired, take ordinary screw-nuts and convert them into
lock-nuts in the manner hereinbefore described.
Having now particularly described and ascertained the nature of my said invention
and in what manner the same is to be performed, I wish it understood that I
claim:-
First The above described method of manufacturing lock-nuts such as are described
in the said former Specifications, consisting in compressing or swaging one end of a
screw-nut while the same is held upon a taper screw-threaded mandrel, substantially
as, and for the purpose, specified.
Second-The improved screw-threaded mandrel (with or without the shoulder)
formed of hard or hardened steel and having some of its screw-threads reduced in
diameter, substantially as, and for the purpose, set forth.
Third The employment, in combination with the taper screw-threaded mandrel, of
a holder for the nuts, substantially as described with reference to Figures 3 and 4, or
Figures 11 and 12 of the drawings for the purpose specified.
Dated thin oth
JT 1007