An Improved Lock-nut.
Year: 1892

page_text: Date of Application, 7th Dec., 1892
Complete Specification Left, 28th Aug., 1893-Accepted, 30th Sept., 1893
An Improved Lock-nut.
EDWARD DERRICK, Mechanic, No. 25 Peas Hill Road, Nottingham in the
County of Nottinghamshire, do hereby declare the nature of this invention to be as
follows:-
The nut is made of metal.
thus forming a lock. The
causes heat and expansion.
I make a slot in the nut. This slot I close together
action of screwing the nut into position on its bolt
When in position it cools and contracts.
Dated this Fifth day of December 1892.
EDWARD DERRICK,
Mechanic, No. 25, Peas Hill Road, Nottingham, Nottinghamshire.
COMPLETE SPECIFICATION
An Improved Lock-nut.
EDWARD DERRICK 25 Peas Hill Road Nottingham Mechanic 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 improved nut is designed to be used with bolts and other screw fastenings
with which nuts are generally used, the object of my invention being the production
of a nut which shall lock itself upon the bolt or other screw fastening when
screwed upon the same, and which may be removed from the bolt or other screw
fastening without injuring the screw thread upon the same.
I have attached hereto one sheet of drawings showing in Fig. 1 an elevation of
my nut partially finished, in Fig. 2 a sectional elevation of the same, in Fig. 4 a
plan of the same and in Fig. 3 an elevation of my nut when finished.
The nuts are made of metal and the blanks for the same may be produced by
forging, stamping, casting, or by any of the usual methods, and they are tapped in
the ordinary manner.
In carrying out my invention I make, by sawing, or by other means, a groove a
across one end face of the nut, the said groove having a depth of about
three eights of the depth of the nut, and the bottom c of it, parallel to the face
in which it is cut. The width of the groove a is about one sixteenth of the depth
of the nut.
The sides of the groove a are then forced towards each other as at 6 Fig. 3 by
any suitable stamp or press.
The nuts may be square, hexagonal or other shape finished or in the black, and
the groove may be cut across the widest or narrowest part of the face of the nut,
or anywhere between these positions.
When the nut is screwed upon the bolt or other screw fastening, the sides of
the groove are forced apart, thus bringing into action the elasticity of the material
of which the nut is made, the reaction of which causes the nut to firmly grip the
bolt, this action being assisted by the heat generated by screwing on the nut.
This causes the nut to expand which afterwards cools and contracts upon the
bolt.

page_text: Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
A nut having a groove across the centre of the same, the bottom of the groove
being parallel to the end face of the nut in which it is cut, and the sides of it
pressed to or towards each other, substantially as and for the purpose shown &
described in the accompanying drawings and Specification.
Dated this 26th day of August 1893.
W. H. POTTER, Wh. Sc.,
Parliament Chambers, Nottingham, Agent for the Applicant.