AN IMPROVED CONSTRUCTION OF LOCKING NUT FOR SCREW BOLTS
Year: 1877

page_text: LETTERS PATENT to Arthur Thomas Timewell, of Clapham Road, in the
County of Surrey, for the Invention of "AN IMPROVED CONSTRUCTION OF
LOCKING NUT FOR SCREW BOLTS."
Sealed the 6th October 1877, and dated the 14th April 1877.
PROVISIONAL SPECIFICATION left by the said Arthur Thomas Timewell
at the Office of the Commissioners of Patents on the 14th April 1877.
ARTHUR THOMAS TIMEWELL, of Clapham Road, in the County of Surrey.
IMPROVED CONSTRUCTION OF LOCKING NUT FOR SCREW BOLTS."
"AN
This Invention has for its object a simple construction of locking nut for enabling
the same to be more readily fixed or locked when screwed down upon the bolt in
the usual manner, and employed for securing fish joints of rails, plumber-block
bearings, or otherwise, and consists in forming the said nuts in two parts, united
and held together by bevelled cotters or bars fitted tightly within corresponding
channels or grooves on the inner surface thereof, so as to form thereby one entire
nut tapped and finished in the usual manner.
The annexed Drawings represent at Fig. 1 a side view of the improved nut,
shewing the same locked upon the bolt; Fig. 2, top or plan view of the nut; Fig. 3,
sectional side elevation of the nut taken through the dotted line; and Fig. 4,
detached views of the bevelled cotter.
In each Figure the same letters of reference denote similar corresponding parts.
A, the nut formed in two parts B and C, as shewn; D, bevelled indentations or
grooves for receiving the cotters or locking bars E, and for holding the two parts of tho
nut together, and giving the locking strain by driving one of the cotters through from
the opposite side; the said cotters being slightly wedge-shaped for raising the nut
against the thread on one side of the bolt, as at F, by which means the locking is
effected, or the unlocking of the same in like manner, by reversing or pushing the
cotter back in the opposite direction.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Arthur Thomas Timewell in the Great Seal Patent Office on the
12th October 1877.
ARTHUR THOMAS TIMEWELL, of Clapham Road, in the County of Surrey.
IMPROVED CONSTRUCTION OF LOCKING NUT FOR SCREW BOLTS."
<< AN
This Invention has for its object a simple mode of constructing locking nuts with
the view of enabling the same to be permanently locked upon the screw bolts, and
prevented from turning back or becoming loose when securing fish joints of rails,
plumber-block bearings, and other kinds of machinery in which nuts and bolts are
employed, and consists in forming the said nuts in two parts, and uniting and holding
the same together by bevelled cotters or bars fitting closely within corresponding
undercut grooves or channels slotted out or otherwise indented on the inner surface
of the said halves thereof, so as to form one entire nut for being tapped, fitted, and
finished in the usual manner; at the same time admit of being firmly locked upon the
bolt, as required, by mearly forcing the thick end of one of the wedge-shaped cotters
partly through from the opposite side, for the purpose of separating or slightly
raising the two parts aforesaid from each other, and thereby jamming the threads
together upon the screw of the bolt.
And in order that my said Invention may be more fully understood and readily
carried into effect, I now proceed to describe the same by aid of the accompanying
Drawings, reference being had to the letters and figures thereon marked, (that is
to say),
Fig. 1 of the annexed Drawings represents a vertical front view of my improved
nut, shewing the mode of locking the same upon the threads of the screw bolt ;
Fig. 2, top or plan view thereof; Fig. 3, edge view of same separately shown.
Figs. 4, 5, and 6, corresponding views shewing the nuts unlocked and partly in
section.
Fig. 7, side elevation of the nut shewing the method of wedging open the two
halves, and locking the same upon the thread of the bolt; Fig. 8, perspective front
view of the same.
Fig. 9, detached plan view of the two halves of the nut with undercut slots or
dovetail grooves cut therein.
Fig. 10, side view of the two halves united and held together by the two cotters,
so as to form a single locking nut as aforesaid.
Fig. 11, transverse vertical section taken through the dotted line in Fig. 9;
Fig. 12, external side view thereof; and Figs. 13, 14, and 15, detached end and side
views of the tapered cotter separately shewn.
In each Figure the same letters of reference denote similar corresponding parts.
A and A', the two parts of the nut united and held together by the cotters, so as
to form a nut of the ordinary thickness; B and B', dovetail wedge-shaped cotters;
C and C, longitudinal corresponding channels or grooves slotted out or otherwise
formed in the two halves, as seen at Fig. 9, for receiving the said cotter and holding
the two parts together and giving the requisite locking strain and cant to the
threads upon the bolt, as above described and shewn at Fig. 7; D, D, the ordinary
bolt.
In conclusion to the foregoing description I would here briefly note that the shape
or dimensions of the nuts and cotters or grooves may bo otherwiso varied and
arranged, or receive such other modifications as in practice may be found necessary.
Having now fully described and ascertained the nature of this my said Invention
and the manner in which the same is to be performed and carried into effect, I
would have it clearly understood that I do not by any means intend to confine,
myself to the precise details herein-before set forth and described, as the same may,
be otherwise varied without departing from the general principle of this my said
Invention, nor do I claim as new and of my said Invention the exclusive use of the
several parts, combinations, and processes, except when the same are employed in

page_text: and for the purposes of my said Invention, which I hereby declare to consist in
uniting and holding the two parts of the nut together through the medium of the
wedge-shaped dovetail cotters and corresponding indentations or grooves, and giving
the locking action to the nut by forcing the thick edge of one of the cotter between
the two halves, and jamming the threads against the screw bolt in the manner and
for the purposes herein-before set forth and described.
In witness whereof, I, the said Arthur Thomas Timewell, have hereunto set
my hand and seal, this Eleventh day of October, in the year of our Lord
One thousand eight hundred and seventy-seven.
ARTHUR T. TIMEWELL. (L.S.)"