Year: 1889

page_text: 1 WILLIAM WILSON HORN of the Firm of Horn & Son Patent Agents of
151 Strand Middlesex (a communication to me from abroad' by Samuel Henry Ray
and Richard Hanlon both of the City of St. Louis State of Missouri United States
of America Gentlemen) 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:-
This my invention relates to certain new and useful improvements in Nut Locks
and I hereby declare the following to be a full clear and exact description of the
same reference being had to the accompanying drawings wherein
Fig. 1 is a perspective view of devices embodying my invention Fig. 2 is a
longitudinal section of the same Fig. 3 is a perspective view of the nut Fig. 4 is an
enlarged end view of the nut with the bolt and locking pin in section for the purpose
of showing distinctly that the locking pin is of greater diameter than the depth of
the eccentric groove of the nut, and also how the edges of the bolt threads are
abraded in driving in the locking pin or key Fig. 5 is a sectional view of the nut.
Fig. 6 is a detached view of the key. Like figures and letters refer to like parts
wherever they occur.
My present invention relates to that class of nut-locks wherein the nut is provided
with an eccentric or cam groove and a key is used to bind on the bolt and prevent
the turning of the nut on the bolt.
The advantages of the class of nut-locks referred to, are first, the simplicity of the
construction which requires little change in the present form of the nut, and none in
the bolt; and second, the ability to lock the nut at any point on the bolt.
The main features of the present invention lie in the character of the key, which
is to be of harder material than the bolt with which it is to be employed, as well as of
slightly greater diameter than the deepest part of the eccentric slot in the nut, and
preferably of cylindrical form, so that when driven, it (the key) shall slightly groove
the threads of the bolt so as to prevent the subsequent cutting of the key by the
bolt threads.
t
There are other features incident to the character of the key both as to material
and form all of which will hereinafter more fully appear.

page_text: I will now proceed to describe my invention more specifically, so that others
skilled in the art to which it appertains may apply the same.
In the drawing A indicates a bolt of any ordinary character with full thread, and B
the nut employed therewith. The nut B is of the class provided with a groove
eccentric to the aperture of the nut, and which crosses the threads of the nut.
The exact form or location of the groove is not material, provided the bottom is of
such character as to cause the key to grip the bolt when the nut is reversely rotated,
but experience has shown that a concave or rounded.bottom of the groove is not so
desirable as a flat bottom, and that owing to the greater amount of metal in the
angle. The groove can be there placed with less liability of weakening the nut. The
preferable form for the eccentric groove of the nut is that shown in the drawing,
that is to say with two parallel sides and y the one being substantially tangential
to the circle of the aperture E, or a circle described with the axis of the bolt for a
centre, and longer than the other or opposite g, and the bottom of the groove flat as at h.
C Fig. 6 indicates the key used for locking the nut, which may be said to
consist of the three members, the locking pin c, the driving and drawing section b,
and the securing arm a, (or spring catch) all of which members are desirable but
each of which has a function in addition to the combined function of the parts.
The locking-pin c must be slightly greater in diameter than the depth of the
eccentric groove D of the nut, so that it shall not be capable of independent move-
ment in the eccentric groove, and is always inserted with force, as by driving, and it
must be of a harder nature than the bolt. A with which it is used, in order that when
driven it may slightly groove or abrade the threads of the bolt, otherwise subsequent
jar or vibration of the nut or bolt will cause the threads of the bolt to groove the
key and destroy the lock.
The locking pin c is preferably round as the cam action is more perfect, and there
is less tendency of the pin to leave its seat in the abraded threads of the bolt, or to
slide on said threads when the bolt and nut are jarred.
As the pin has to be driven with considerable force in order that it may abrade
the threads of the bolt, and as considerable force is required to subsequently draw the
pin a driving section of considerable gripping surface, and of considerable rigidity
is desirable and as the lock is frequently used where the holt and locking pin are in a
vertical position a securing arm a (or spring catch) is desirable.
In order to form this key (Fig. 6) I select steel wire of slightly greater diameter
than the depth of the eccentric groove in the nut B, which wire as found in the
market is soft and may be readily bent, and at a point to be determined by the
thickness of the nut and the length of the driving and drawing head required, fold
said wire (as at (b) upon itself, bending the wire the second time at right angles (as
at k) where the driving and drawing section is to terminate and then (as at 7) the
third time to form the locking arm a parallel with the locking pin c the end of the
locking arm a terminating in the tooth 'c' which may either enter a hole in the edge
of the nut B or a recess in the back of the nut B as shown in the drawing. If
desired the head and sides of the drawing and pulling section may be flattened which
will give greater gripping surface for withdrawing the key.
When the key (fig. 6) has been thus formed it is heated and hardened or tempered
in such a
manner as to render the locking pin harder than the bolt as before
specified and this together with the parallel fold of metal will so stiffen the driving
section (6) that the key can be driven readily, which would not otherwise be the case,
and will impart a spring like or catch character to the securing arm a.
To facilitate insertion and removal of the key it is desirable to groove or bevel the
outer edges of the nut B as indicated at d and e, as the tooth c¹ of the securing arm
can then ride up and over the edge of the nut without hindrance.
To further facilitate the insertion of the key into the eccentric groove of the nut,
and to prevent the chipping out of small pieces of the bolt threads, it is desirable to
have the end of the locking pin.c bevelled as shown in the drawing at m.
The devices being of substantially the character herein before described will be
used as follows:-The nut B is screwed upon the bolt A until it has reached the

page_text: desired position, the end of the locking pin c of the key C is then entered in the
eccentric groove D and forcibly driven home so that in its passage it abrades
the edges of the bolt threads, forming slight transverse nicks or grooves which it is
enabled to do by reason of its harder nature, which nicks form a seat for the key in
which it must remain, and consequently the key can never ride on the threads of the
bolt so as to be grooved or cut thereby.
I am aware that nut-locks have heretofore been devised on the principle of the
wedge or cam action due to an eccentric groove in the nut and a spring acting cam.
I am also aware that nut locks have beretofore been devised in which a radial groove
in the bolt and a corresponding groove in the nut have been used in conjunction with
a locking pin which engaged in both grooves; and I am further aware that nut locks
on the pawl and rack principle have been devised, but all of the aforesaid devices
have the disadvantage of complicated devices which render them too expensive, and
too liable to become inoperative for the purposes intended, while most, if not all of
such devices either necessitate the securing of the nut at certain predetermined points
in its rotation, or, if on the simple wedge or cam principle result in the grooving of
the locking key by the threads of the bolt so that the device shortly becomes
inoperative.
As herein-before specified, I have previously devised the combination of an
eccentrically grooved nut with a locking pin of greater diameter than the depth of
the eccentric groove so as to be driven therein to form a lock, and do not herein
broadly claim the same, but I have discovered that unless the said locking pin or key
be sufficiently harder than the metal of the bolt so as to groove the threads of the
bolt slightly in its passage, and thus forming a lock which combines the principles of
the smooth cam or wedge and the pawl and ratchet, the life of the lock will be more
or less limited according to the extent of vibration or jar to which the devices are
subjected.
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 :-
:-
1st. The combination in a nut lock, of a full threaded bolt; a nut having an
eccentric key groove and a bevelled edge as at d and e; and a locking key or pin
having a spring arm adapted to clasp the nut, substantially as and for the purpose
specified.
2nd. A tempered steel locking key for nut locks, having the round locking section;
the folded driving and drawing section, and the spring arm formed from a single
piece of wire and shaped to clasp the nut substantially as and for the purpose
specified.
Dated this 1st day of January 1889