IMPROVEMENTS IN SCREW NUTS AND IN THE MODE OF LOCKING THE SAME UPON THE BOLTS
Year: 1877

page_text: LETTERS PATENT to Alfred Ellis Harris, of Mile End Road and Finsbury
Circus, in the 'County of Middlesex, for the Invention of "IMPROVEMENTS IN
SCREW NUTS AND IN THE MODE OF LOCKING THE SAME UPON THE BOLTS."
PROVISIONAL SPECIFICATION left by the said Alfred Ellis Harris at the
Office of the Commissioners of Patents on the 16th April 1877.
ALFRED ELLIS HARRIS, of Mile End Road and Finsbury Circus, in the County of
Middlesex. “IMPROVEMENTS IN SCREW NUTS AND IN THE MODE OF LOCKING THE
SAME UPON THE BOLTS."
This Invention has for its object a simple and expeditious method of constructing
screw nuts with the view of enabling the same to be mauufactured and employed at
less cost and with a better locking action than others hitherto in use for the said
purpose, and consists in forming the nut in two parts, one having a slot or channel
stamped on the inner surface of one half thereof, and the other a raised feather or
projecting beading fitting into the slot on the counterpart; a staple or keyway is
also formed on the opposite inner side of the nut, so that when the two halves are
placed together and screwed upon the bolt as required the key is inserted and
pressed or driven between the two halves to partially divide the same, and cause
the tapped portion of the nut to impinge rigidly against the thread of the bolt, and
thereby prevent it getting unscrewed or loose upon its seat; the key I prefer to
be flat, solid, and longitudinally tapered towards one end and slit if necessary for
bending back like a linch pin. I also unite the two halves or body of the nut by
means of a dovetail in conjunction with the other portion, as above described, or
otherwise form the two halves with plain channels and screwed keyways and
staples to be struck out by dies on each half, or otherwise moulded as required, so
as to be fitted and bolted together in like manner to the above.
Fig. 1 in the accompanying Drawings represents my improved nut and mode of
locking the same upon the bolt; Fig. 2, top or plan view thereof; Fig. 3, sectional
side elevation.

page_text: Fig. 4, two halves of the nut shewing the inside surfaces and mechanical
arrangement of the parts.
Fig. 5, detached view of the keys.
Fig. 6 and 7, side view and section, shewing the dovetail mode of uniting the two
halves of the nut; and Figs. 8, 9, and 10, similar corresponding views, shewing the
nut in its moulded form.
In each Figure the same letters of reference denote similar corresponding parts.
A and B, the two parts of the nut; c, raised feather; D, channel receiving the
feather; E, keyway formed in one or both halves; F, key, plain, screwed, or
otherwise; G, slit for turning back; H, tapped portion of nut for receiving the
screw of the bolt I, as shewn; J and J¹ dovetail joint.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alfred Ellis Harris in the Great Seal Patent Office on the 16th
October 1877.
ALFRED ELLIS HARRIS, of Mile End Road and Finsbury Circus, in the County of
Middlesex. "IMPROVEMENTS IN SCREW NUTS AND IN THE MODE OF LOCKING THE
SAME UPON THE BOLT."
This Invention has for its object a simple and expeditious method of constructing
screw nuts with the view of enabling the same to be manufactured and employed at
less cost and with a better locking action than others in use for the said purpose,
and consists in forming the said nuts in two parts, one half having a slot or channel
stamped on the inner surface thereof, and the other a raised feather or projecting
beading fitting into the said slot on the counterpart; a staple or keyway is also
formed on the opposite inner side of the nut, so that when the two halves are placed
together and screwed upon the bolt as required for the purpose of being locked, the
key is inserted and pressed or driven between the two halves to partially divide the
same and cause the tapped portion of the nut to impinge ridgedly against the threads
of the bolt, and thereby prevent it getting unscrewed or loose upon its seat; the
key I prefer to be flat, solid, and longitudinally tapered towards one end, and slit if
necessary for bending back like a linch pin. I also unite the two halves or body
of the nut by means of a dovetail joint in place of the raised feather aforesaid, and
slightly concave or hollow out the inner surface of the two halves, and thereby
enable the extreme edges of the said parts to be brought together without leaving
any perceptible intervening space or opening between the same when screwed
together upon the bolt, or otherwise form a channelled keyway in one or both sides
of each division by stamping, slotting, or otherwise as required.
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 represents my improved nut and mode of locking the same upon the bolt ;
Fig. 2, top or plan view thereof; Fig. 3, sectional side elevation.
Fig. 4, the two halves of the nut, shewing the inside surfaces and mechanical
arrangement of the parts; Figs. 5 and 6, side elevation thereof.
Figs. 7, 8, and 9, detached view of the locking keys.
Figs. 10 and 11, side view and section, showing a dovetailed mode of uniting the
two halves of the nut in place of the feather above described.
Figs. 12, 13, and 14, similar corresponding views, shewing the nut with the key-
way formed on both sides of the same.
And, Fig. 15, a perspective view of a nut complete.
In each Figure the same letters of reference denote similar corresponding parts.
A and B, the two parts of the nut; C, raised feather; D, channel receiving the
feather; E, keyway formed in one or both halves of the nut; F, serrated wedge or

page_text: plain tapered locking key of any required form with slit G for twisting back, also
to prevent its working out; H, tapped portion of nut for receiving the screw of
the bolt I, as shewn; J and J', dovetail joint; K and K³, concave or hollow for
bringing the parts of the nut closer together and giving freedom of action to
the tapped threads in locking the same upon the bolt; L and L', edge or boiler
of concavities formed by the outside or body of the nut for keeping the surfaces
together.
The action and locking arrangement of my improved nut is as follows:-The two
portions of the nut are placed together and held or retained in position by the
raised feather and channel aforesaid, they are then screwed down upon the bolt in
like manner to an ordinary nut, the tapered key is next inserted and pressed or
driven forward between the hollowed concavities formed in each half of the nut, so
as to cant or change the natural inclination of the threads and jam them one against
the other, and thus prevent it getting unlocked until the key is withdrawn.
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 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 iny said Invention the exclusive use of the several parts,
combinations, and processes except when the saine are employed in and for tho
purposes of iny said Invention, which I hereby declare to consist,―
Firstly. In constructing locking nuts in two parts slightly concave or hollowed
out on the inner surface thereof, and fitting and keeping the same together by a
raised feather and tightening key or wedge for canting the tapped threads of the
nut against the screw of the bolt and giving the locking action thereto.
Secondly. Employing a dovetail joint in lieu of the raised feather for securing the
two portions of the nut together, as before described.
Thirdly and lastly. Uniting and binding the edges of the two halves of the nut
firmly and closely together through the medium of the inner hollowed surfaces or
concavities aforesaid, in the manner and for the purposes herein-before set forth and
described.
In witness whereof, I, the said Alfred Ellis Harris, have hereunto set my
hand and seal, this Fifteenth day of October, in the year of our Lord One
thousand eight hundred and seventy-seven.
ALFRED ELLIS HARRIS. (L.S.)