IMPROVEMENTS IN NUT LOCKS
Year: 1882

page_text: LETTERS PATENT to Alfred Julius Boult of the firm of W. P. Thompson
"
& Boult Agents for Foreign Patent Solicitors of 323 High Holborn in the
county of Middlesex and 6 Lord Street, Liverpool in the county of
Lancaster Engineer for an invention of IMPROVEMENTS IN NUT LOCKS
A communication to him from abroad by William Mack and John. B. Deeds
both of the City of Terre Haute in the county of Vigo and State of Indiana
in the United States of America
COMPLETE SPECIFICATION filed by the said Alfred Julius Boult at the
Office of the Commissioners of Patents on the 2nd October 1882.
ALFRED JULIUS BOULT, of the firm of W P Thompson and Boult Agents for
Foreign Patent Solicitors of 323 High Holborn in the County of Middlesex
and 6 Lord Street Liverpool in the County of Lancaster Engineer. IMPROVE-
MENTS IN NUT LOCKS A communication to me from abroad by William Mack
and John B. Deeds both of the City of Terre Haute in the county of Vigo, and
state of Indiana in the United States of America,
This invention relates to the class known as nut locks. The object of this
invention is to prevent the nuts on bolts from jarring off, locking the nut to the
bolt in such manner as to prevent its unscrewing when the bolts are subjected to
any unusual or violent action, such as is the case with rail road fish plates, bridges
and working parts of machinery. To this end my invention consists in a nut
provided on its face with a V shaped angular recess made nearly tangential to the
bore of the nut in combination with a straight spring brace located in said recess
and projecting into the bore of the nut on a line outside the center, and adapted
to engage with the threads of a bolt on a line oblique to the longitudinal axis of
said bolt whereby the increased strain produced by the unscrewing of the nut,
increases, the bite of said lock brace in the manner set forth. In the accompanying
drawings, Figure 1 represents a perspective view of a bolt with my improved nut
clearly showing the √ shaped angular recess and the spring brace engaged in the
threads of the bolt.

page_text: Figure 2 is a view of the face of the nut and the end of a bolt screwed into the
nut clearly showing the straight spring brace in position and Figure 3 shows a
transverse section of the nut taken on a line of figure 2. Figure 4 is a face of
the nut with the bolt omitted for the purpose of showing the extension of the
spring into the bore of the nut, through the angular recess.
This figure shows the depth of the recess and the side of the spring brace the
edge of which rests against the thread of the bolt. a designates the nut and ba
bolt screwed therein, c is the V shaped angular recess extending say one-fourth
of an inch into the face of the nut, One wall of the recess is nearly tangential
with the circumference of the bore of the nut and the other nearly at a right line
through its center the two walls terminating at one corner of the nut; d is a
straight spring brace located in the recess c and arranged on a chord of the arc of
a circle to a right line through the diameter of the bore of the nut, so that it will
be seen that the spring brace is on an angle to the circumference of the nut and
also on an angle to the center of the same.
The principle upon which my nut lock is constructed is well known that is, that
a straight or perpendicular prop or brace will stand a greater longitudinal pressure
on its horizontal plane than a bent prop or brace would, Hence when I throw the
stress on a straight line, or chord to the arc of a circle oblique to its axis I produce
a leverage against the point of resistance or turning of the circle equal to the
distance the chord of the arc is from the center of the circle_thus.
Therefore the brace or spring recess in the nut is near tangential to the bore
thereof on a plane oblique to the longitudinal axis of the bolt, it having a direction
oblique to the motion of the nut turning on the bolt which brings the lock brace
in contact with the thread of the bolt on a straight line beyond a plane of its
longitudinal axis or center so that when the nut is turned backward the brace lock
bites the thread of the bolt in such manner as to throw the entire strain on a
direct line with the spring, thus the greater the strain the greater will be the bite
on the thread so that the spring brace takes the form and produces the result, a
straight incline prop or brace would to a perpendicular or standard In this way
the nut could not turn backwards until a slice of the thread would be forced off.
The nut is made as follows; It is first punched cutting at the same time the
angular recess; the straight spring is then inserted and the walls of the recess are
closed or hammered together on the spring which rigidly holds the spring in
position. The nut is then screw threaded when it is ready for use.
It is obvious
that the spring may be suitably fastened by other means, but the means described
are preferred. Thus a cheap simple and effective nut lock is produced easily
made and applicable to any sized bolts in general use. I am aware that nuts have
been made with recesses in their faces and that curved springs in connection with
grooved bolts have been made and that nuts have been made with holes through
them and combined with spring pawl and ratchet, but I am not aware that a nut
provided with a V shaped recess in its face tangential with the bore of the nut and

page_text: having a straight spring brace inserted and rigidly held in said recess, the spring
being on an angle to the center of the nut and oblique to the circumference of the
bolt was ever before made.
Therefore what I claim and desire to secure by Letters Patent is :-
1st A nut provided on its face with a V shaped angular recess made nearly
tangential to the bore of the nut, in combination with a straight spring brace
located in said recess and projecting into the bore of the nut on a line outside the
center and adapted to engage with the thread of a bolt on a line oblique to the
longitudinal axis of said bolt, whereby the increased strain produced by the
unscrewing of the nut increases the bite of said lock brace in the manner set forth
and described.
2nd A nut provided on its face with an angular recess nearly tangential to the
bore of said nut and a straight spring brace or lock arranged at an angle to the
longitudinal axis of the bolt in combination with said bolt, the spring brace being
rigidly held in position by the sides of the recess compressed together at its
narrowest part substantially as described.
3rd A nut provided with a V shaped angular recess nearly tangential to the
bore thereof, and a straight spring brace fastened by the walls of the recess and
projecting into the bore of the nut, said spring brace being adapted to engage the
thread of a bolt substantially as described.
4th A nut provided on its face with a V shaped angular recess near tangential
to the bore thereof, a straight spring brace suitably fastened in said recess at one
of its ends, the other end projecting into the bore of the nut and adapted to engage
with the thread of a bolt when the bolt is turned backwards and have lateral
motion in the larger portion of the recess when the spring is disengaged substantially
as described.
5th As an article of manufacture a nut provided on its face with a V shaped
recess near tangential to the bore of the nut and with a straight spring suitably
fastened therein by the walls of the recess said spring being adapted to engage the
threads of a bolt when turned backwards substantially as described.
6th The method herein described of making nut locks by first punching the nut
and making an angular recess in the face thereof, then inserting a spring brace in
said recess, then closing together the walls of the recess while in a heated condition
upon one end of the spring brace and finally cutting a screw thread in the nut as
described.
In witness whereof I the said Alfred Julius Boult have hereunto set my hand
and seal this second day of October in the year of our Lord, One
thousand Eight hundred and Eighty-two.
ALFRED J. BOULT. (L.S.