IMPROVEMENTS IN APPLIANCES FOR LOCKING BOLTS AND NUTS
Year: 1884

page_text: We ARTHUR THOMAS ALLEN and HENRY CAVILL both of the Hallamshiro
Engineering Works Arundel Street, Sheffield, in the County of York, Engineers dọ
hereby declare the nature of our said invention for IMPROVEMENTS IN APPLIANCES
FOR LOCKING BOLTS AND NUTS to be as follows:-
°
Our invention relates to improvements in appliances for locking bolts and nuts,
and is especially applicable to the nuts of fish joints of railway rails; it may also
be applied to other bolts or nuts that are liable to be shaken loose, such as piston
bolts.
In carrying out our invention in its application to the nuts of the bolts used in
fish joints, for example, the bolt being an ordinary screw bolt and the nut an
ordinary square nut; the fish plates on both sides of the rail are provided with
squared holes, one being to receive the square neck of the bolt, and the other to
receive a similar square, projecting from a washer hereafter described.
The locking appliance consists of two toothed washers, the one which is placed
over the bolt before the nut is screwed on, is provided with a squared projection
which fits into the hole in the fish plate by which it is prevented turning round.
Upon its outer face we form indentations or teeth, preferably resembling undercut
ratchet teeth, these we prefer to make upon a narrow annular surface, recessing
the central portion round the bolt hole to permit the nut to take a flat bearing
against it.
The locking washer which has no squared projection, is provided with a
corresponding annular ring of teeth, and a squared hole, so that it can be placed
over the nut, when the nut is screwed up to the first washer.
The appliance is used as follows,-The bolt being in position and projecting
through the fish plates, the first washer is placed over it and the projection passed
into the squared hole in the fish plate, the nut is then screwed upon the bolt
down to the face of the washer inside the circle of teeth, and the locking washer
placed over it, so that the teeth engage; if the teeth do not fall into gear the nut
must be tightened a little until they do, then by reversing the nut the undercut
portions engage and the nut is securely locked upon the bolt.
It will thus be seen that the nut cannot either be shaken loose or be removed
from the bolt, until it has been tightened up sufficiently to allow the teeth to be
disengaged and taken out of gear.

page_text: In the application to vertical bolts on which the nuts are screwed from the top,
it is not absolutely necessary to make the teeth upon the washers undercut as
before described.
The locking washer instead of having the hole made completely through as
before described, may be cap shaped so as to enclose the nut or bolt head and
protect it from the weather. In Piston blocks, the first washer may be dispensed
with, and suitable slots formed in the solid material of the block, the locking part
being cap shaped and provided with teeth or catch pieces to engage with the slots.
1001

page_text: cap the screw may be turned. A recess is made in the metal of the block to
receive the head of the screw and also the cap when placed over it, the side of the
recess being provided with oblique grooves or undercut grooves J-to receive the
locking bits I, which are equivalent in their operation, to the undercut teeth F
before described.
We wish it to be clearly understood that we do not bind ourselves to the exact
configuration of the locking appliances nor to the number or shape of the teeth or
locking bits as these may be varied without departing from tlie spirit of our
invention.
.1
Having now particularly described and ascertained the nature of our said
invention and the manner in which it may be carried into practice, we declare
that what we claim is :—
1st The appliances for locking bolts and nuts, substantially as herein described
+
and illustrated.
2nd In locking bolts and nuts, the use of locking washers, having undercut teeth,
or their equivalents (such as pins and holes) for the purpose 'specified, and
substantially as described.
3rd A locking Cap as shown in Figs 4 and 5, provided with locking bits, for the