IMPROVED MEANS FOR LOCKING NUTS AND SCREWS
Year: 1884

page_text: I ARTHUR WILLIAM LOVELL REDDIE, of the Office for Patents 6, Bream's
Buildings, Chancery Lane in the County of Middlesex, Patent Agent, do hereby
declare the nature of my invention for " IMPROVED MEANS FOR LOCKING NUTS
AND SCREWS," and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:--
A practically useful safety or locking appliance for screw nuts should fulfil three
requirements.
1. It must be strong enough in itself to hold the screw nut fast in position.
2. It must remain fast, notwithstanding the influence exerted on the screw
connections by the continual shaking or jarring to which they are exposed.
3. It must be capable of easy removal or detachment without damaging any part
thereof, and of being as easily replaced, so that no obstacle may stand in the way
of the tightening or loosening of the nut.
Such a safety appliance is that hereinafter described with reference to the
accompanying Drawings.
:
A washer (usually of hardened steel) provided with a suitable aperture for the
reception of the screw bolt is formed with a shoulder, ridge or projection, such
as a, extending from the central aperture to the outside edge, and the washer is
cut through near the said projection and so bent up that the part provided with
the projection or ridge stands, or is inclined, slightly upwards, and operates as a
spring.
The under or downward surface of the screw nut is provided with several radial
grooves b corresponding in contour with the projection or ridge a. The projection a
and the grooves b b are preferably rounded as seen in Figs: 1 to 3.
In order that the screw nut may be tightly screwed up against the adjacent
surface, and that after the tightening up, the projection may take into one of the
grooves of the screw nut, there will be employed either, (as in Fig: 3) a washer, in
which the elastic blunt-edged ridge or projection a is produced by the thinning, by
means of pressure, of a portion, c, of the metal or material of which the washer is
made; or, (as in Fig: 2) a second washer with a recessed portion d is laid or bent,
thereunder, and allows of the projection or ridge a dipping into it; or again,

page_text: as in Fig: 1 a recess e is made in the surface of the object to be held fast by the
bolt and screw nut, or in the surface of the underlying or adjacent plate.
On the tightening up of the screw nut, the elastic projection will either, as in
Fig 3 be pressed flat on to the object to be screwed up, and in the same plane with
the adjacent surface of the washer; or-as in Figs: 2 and 1 into the recess formed
by the cut away portion, as will be clearly understood from the Drawing, until on
the further tightening up of the nut, it springs into one of the grooves made
in the washer for its reception. The rounding off of the projections and of the
grooves for the reception of the same permits of the untwisting or slackening of
the nut.
:
If in the case of the arrangement shown at Figs 2 and 1, the security of the
screw nut is desired to be increased in view of very exceptional vibrations, a pin 8
(Figs 2 and 1) should be driven into the recess (d or e) after the tightening up of
the nut, such piñ being capable of being withdrawn when required.
.
When employing a pin of this kind the recess in the surface of the object to be
held fast by the bolt and screw nut, or in the "adjacent surface"; as well as that
In the screw nut, may be placed radially to the screw bolt, in which case the disc or
'washer with its elastic ridge or projection may be dispensed with (see Fig: 4).
If it is not convenient so to arrange this pin that the weight or position of the
same will prevent its falling out, it should be provided at its outer end with a bent
portion or hook (see Fig: 5) and after insertion turned round so that the bent or
hooked end takes into a corresponding recess made in the adjacent underlying plate
or surface; or the groove in the washer is continued on the opposite side of the
screw bolt and the nut is secured by two pins, which may conveniently take the
form of the two ends of a spring, which will press the pins with the points towards
one another, and therefore against the screw bolt (see Fig: 6).
If two screw nuts are situated not too widely apart, both nuts may be secured by
one such spring (see Fig: 8); one pin or point being inserted in the radial recess or
cavity beneath the one nut, and the other pin or point in the recess beneath the
other nut.
C. If the objects to be screwed together are produced by rolling in rolling mills,
such, for instance as railway fish-plates, the groove may be formed therein by rolling
during the process of manufacture (see Fig: 7); and will then be made of the entire
length of the article.
The spring, that is to say, the elastic connection between the two pins x and y
may take any approved form such as those shewn in the various views in Figs: 6,
.7, 8, 9 and 10.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
c 1. The means hereinabove described for locking in place nuts and screws, and
• consisting in the use of radially grooved screw heads or nuts, in combination with
one or more spring tongues, points, or projections, interposed or inserted between
the said grooved head or nut and the surface of the article against or adjacent to
which the said head or nut is screwed.
2. The use in combination with a screw nut or screw head having radial grooves
on its underside, of a disc or washer provided with a spring tongue, nose, or ridge,
adapted to snap into and engage with one of the said radial grooves and prevent the
said nut or screw, when screwed home, from working loose, substantially as described
with reference to Figs: 1, 2 and 3 of the drawing.
3. The use in combination with a screw nut or screw head having radial recesses
on its under side, and a perforated disc or washer, or an underlying plate having a
hole through it and a surface-cut or recess radial thereto, of a pin or its equivalent
adapted to engage with one or other of the recesses in the said screw nut or screw
head, when properly screwed home, substantially as and for the purpose set forth.
4. The combination with a screw nut or screw head having radial recesses on its
under side, and a plate or block of metal having one or more holes for the reception

page_text: of a screw or screw bolt, of a groove or grooves extending radially from or between
such hole or boles, and wire pins or their equivalent united by a spring connection
and adapted to enter the said recesses when brought into coincidence, and firmly
lock together the adjacent faces when the nuts or their equivalent are screwed
home.
5. The combination with a metal plate having a hole or holes for the reception of
a screw bolt or screw, and a continuous groove in its surface cutting the axes of
said holes at right angles thereto, of radially recessed screw nuts or screw heads,
and pins or projections united by a spring connection, and adapted to engage with
the groove in the plate and with a recess in each of the screw nuts or screw heads,
as and for the purpose set forth.