Improvements in Lock Nuts.
Year: 1891

page_text: Date of Application, 29th Sept. 1891-Accepted, 3'st Oct., 1891
Improvements in Lock Nuts.
I, TOM J. NICHOLL of 206 Cass Street, Chicago, County of Cook, State of
Illinois, United States of America, Merchant, 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 an improved construction of a nut, whereby it shall be
adapted effectually to lock itself against the object to which it is applied for
holding the bolt on which it is screwed.
The accompanying drawing shows my improved nut by a perspective view.
A is a nut, which may be of any desired shape and size, but which is preferably
formed of steel, though it may be formed of iron or brass, or other material. At
opposite sides of the threaded opening r, I form on the bearing-surface of the nut,
a springy projection q, which should extend radially from the opening r, to the edge
of the nut, though it may extend at a different angle and be shorter than stated.
Two of these springs 9 are shown in the drawing, as extending in contrary
directions at diagonally opposite sides of the threaded opening, and that number is
preferred, though it may be increased; and it is even within the spirit of my inven-
tion to provide but one.
I form the spring projection 9 (though it may be otherwise formed, but, I
believe, not so readily) by means of a suitable die, which operates to cut diagonally
into the surface p at one or more sides of the opening ", and bend the cut portion q
outward to, or substantially to, the form illustrated, causing it to project beyond
the surface p and form a spring indenting pawl having a recess behind it in the
bearing-surface of the nut to receive the spring pawl as the nut is turned home. If
the thread in the opening were caused to extend to the surface p, in forming the
spring indenting pawls q, the die would cut the thread, leaving a portion thereof
on the inner surface of each pawl, which might interfere with the screwing of the
nut on the threads of the bolt. Hence I form a plain circular recess, n, extending
from the surface p to such a depth in the opening as the die is caused to pene-
trate, of greater diameter than the threaded portion of the opening, whereby in
forming the thread, the threading implement cannot operate in the recess.
The nut is applied on a bolt in a position to force its surface p against the
object to be fastened, thereby causing the spring 9 to be forced backward but,
in resisting the pressure, to indent the surface of the said object (as the fish-
plate of a railway-rail). The resilience of the spring alone tends, by the resultant
bearing force against the object, to prevent working of the nut; and the indenta-
tion of the surface of the object by the spring further increases the hold or locking
effect.
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 :-
1-A locking-nut provided on its bearing-surface with a spring indenting pawl
integral with the nut, and with a recess behind the pawl to receive the same as the
nut is turned home, substantially as described.

page_text: and provided on its bearing-surface with spring indenting pawls q integral with the
nut, and with recesses behind the pawls to receive them as the nut is turned home,
substantially as described.
Dated this 29th day of September 1891.
W. P. THOMPSON & BOULT,
Agents for the Applicant.