Year: 1886

page_text: Date of Application, 23rd Jan., 1886.
Complete Left, 25th Oct., 1886.
Complete Accepted, 18th Jan., 1887.
.
I, EDWARD HAWKS of 41 Queen Street, in the City of Edinburgh, Commission
Agent, do hereby declare the nature of this invention to be as follows:-
The main object of my invention is to obtain in screws, screw-bolts and nuts all the
advantages whilst obviating the disadvantages of the two ordinary machine screw threads
i,e, the square thread and the V thread, namely to obtain the power and durability arising
from the minimum of friction, together with the absence of out-thrust or distension of
the nut arising from the direction of the bearing faces of the threads of the "square
threaded" screws, in combination with the great mechanical power of the ordinary
V threaded screw arising from its smaller pitch, together with the much greater
strength, or resistance to stripping, of the V thread arising from its fuller base hold on
the bolt and nut.
To that end I form upon bolts and nuts screw threads having their pressure bearing, or
working faces, perpendicular to the axis of the bolts and nuts, and their idle faces more
or less inclined thereto.
A part section of a bolt and nut shows the faces of the threads as the zigzag line
formed by the capital letter N repeated and joined up thus MN, in which the lines
vertical to the axis represent the bearing faces, and the diagonal lines more or less
inclined to the axis, according to the pitch and depth of the thread, represent the idle
faces, or those less requiring to bear strains.
In this way I form a bolt and nut in which the idle moieties of the threads of square
threaded bolts and nuts are replaced by additional threads, or, in which the pitch may
be correspondingly lessened. And thus whilst retaining the well known advantages of
the "square thread" as to lessened friction and the absence of out thrust, there will be
thus added those of extra mechanical power and the resistance to stripping of a well
made V thread, as now in use.
The working and the idle faces of the new threads may meet to form sharp angles
in helical lines at the roots and tips of the threads, or, as in ordinary V threaded screws
all the meeting lines, or angles, may be rounded off; or, as may be preferable in some
cases, as, e, g, where provision for wear is requisite, as in the case of machinery, the

page_text: threads, at their tips and roots, may be more or less flattened without lessening their
depth and with or without altering their pitch.
In bolts and nuts formed as above described with the line of pressure continued
parallel with their axes, as in square threaded screws, not being deflected as in
V threaded screws into a force distending the nuts, any tendency to unscrew arising
from vibration can be met and obviated by simple means quite inapplicable where
there is a force tending to burst the nut as in ordinary V threaded bolts and nuts.
Hence, where the locking of nuts may be requisite with this invention, it can be
attained by simply having a slit, or slot, through the side of the nut, in the direction
of, or more or less parallel with, the axis, at any angle or side. The requisite tightness
can be given in several ways, as in the screwing or afterwards by compressing the
nut such tightness of fit of the threads of the nut on those of the bolt securing their
full use, whilst the amount of tightness can be easily controlled and regulated very
pointedly through the slot, say by a key of a slightly oval form of the prong that
enters the slot, and by a quarter turn round in the slot opens or locks the grip of the
nut on the bolt, even should the slot not go fully through the nut.
In some cases I may slightly undercut or overcut, more or less, the working faces
of the threads, and yet retain the main advantages hereinbefore set forth. To provide
sufficiently for the wear of threads of screws used for power and motion in machinery
and yet secure as much as possible the several advantages herein set forth, many
modifications of threads may be employed. Thus, where only one face of the thread
has to bear much strain as in the lifting screw of screw jacks, etc, the flattening of the.
thread at the tips, etc, as heroinbefore mentioned may be employed. In other cases
the second face of the thread may be in part vertical and in part inclined to the axis.
In other cases the second face may be in "steps," the bearing surfaces being each
vertical to the axis and the rest parallel thereto, and this form might also apply, in
some cases, to both of the faces. In particular where the screws are large, such
" step" forms of faces of the threads are very applicable, the last mentioned form, with
steps' on both faces, being practically a thread with the bearing surfaces all
vertical to the axis, giving increased mechanical power, and strength of threads, and
provision for wear.
"
In the use of steps on both or either face of threads forming the "pyramid" or
semi-pyramid thread, not less than three such facets upon each such face, is likely to
answer the purpose. The same would apply if some of the facets were slanting, upon
any thread with other than the said "step" threads. For locking nuts or bolts with
these screw threads, any of the plans in common use, or otherwise, may be employed,
whether using special washers, or using slits in the nuts in whatever directions or
number, or using distortions, or any of the possible locking devices.
I have devised a number of arrangements of nuts both as to whole nuts and to nuts
in parts to be interlocked together as whole nuts for use, in employing these threads.
In forming entire nuts, they may, for locking purposes, have any feasible number of
slits, or slots, in their sides without detracting from their power and their bearing on
the screws of the bolts. Besides the single slit right through any side or angle of the
nut as hereinbefore set forth, there may be any number, say from one to six, partial
slits, varying with the form of the nut and its uses, and either upon the upper or on
the under side, or even in alternate positions in the circle, on both upper and under
sides. These slits, or slots, may, any or all of them, pass three-fourths, more or less,
down or up through the nut, but leaving a sufficient amount of the nut's material
uncut for holding the nut-parts firmly together as an entire nut, whether on the top,
on the bottom, or on both top and bottom of nut, being preferably formed in stamping
out the nut, and preferably in most cases, in planes passing through the axis. By
combining the slits on both the upper and the under sides, the whole nut may have an
elastic pressure in an inward direction on the bolt, and thus not only keep the threads
in full contact of their bearing surfaces upon each other, in full use, for preventing
stripping, but also give a very completo lock to the nut upon the bolt, being a
compound result made possible with threads that avoid the distension of common
V threads.

page_text: In using several slits on the under side of the nut next the washer, the tendency of
the pressure upon all the working faces of the nut threads will be to slightly relieve
the inspring pressure from the bolt in relief of the locking friction but which will again
return automatically should the pressure on the working faces relax, as from shrinkage
from any cause of the matter compressed by the bolt and nut, such as in wood work,
or fish plates and rails, and the like.
In this invention the absence of out-thrust in nuts favours the formation of nuts in
parts for lowering cost. Already the unscrewed bolt and its nut are formed rapidly
by machinery, but the screwing of them is relatively slow. To expedite the operation
of forming the screw thread on the nuts, each nut may be made in two, or more parts,
and this opens up the nut so that its screw thread may be impressed the same as the
other parts of its form and superfices, all at the same time, with the metal hot. In
this way the nut may be in its two parts, each as quickly formed as a rivet or a nail,
and as readily joined up into one nut as a finished complete article, or passed over into
the market, each half nut a duplicate of the other to be joined up and rapidly inter-
locked, as wanted.
The arrangements for joining and locking the nut-parts in use, may be various and
in each case also very simple. The two parts, or halves, of a nut may be exact
counterparts of each other, or duplicates, and may be formed by the same mould,
except the formation of the thread different on the two parts. The character of the
interlocking parts, projections, cavities, etc, may vary as clasps and hasps, catches and
latches, snecks and bolts. Dove-tails may be used in a variety of ways also, and in some
cases hingo like joinings, fastened by nails, will do. In one method of interlocking
the parts firmly into one nut, they are so formed that when they are placed together
suitably to become one nut, a washer, or hoop, of suitable form and size can be pushed
over projecting parts on the top, or the bottom, of said nut and which form a
continuous circular part around the bolt hole to be encircled and made firm and fast
in such washer or hoop. Either or both of said top and bottom may be so joined up,
and the projections may be slightly overset or rivetted over by the process of pushing
on the washers. These washers or hoops may be at either end of the nut of the same
form or size as the parts of the nut contacled, or otherwise.
Although the screw threads of this invention specially favour nuts thus built up in
parts, because they need not so much coherence in the absence of the out-thrust, yet
these combining and interlocking parts may be made so strong as even to be applicable
to the ordinary V thread, as well as to the square thread, in addition to the various
forms of threads of this invention. These nut-parts may be more particularly suitable
for the larger sizes of bolts and nuts.
Nuts in parts may be produced conveniently by casting in various metals and alloys,
with their threads on, and for machine work, using power, may have them polished
up for working smoothly before being joined up.
In some circumstances, and to facilitate the shaping of the nut-parts, it may be
advisable to roll the material into shapes favourable for expediting the stamping and
impressing the threads. For some purposes it may be advisable to form the threads
in the nut-parts, as well as on the bolts, after they have received otherwise their several
forms, and that either by the hot or by the cold process, and either by compression or
by cutting or by both, in part depending on the characters of the materials. But in
general these should all be fully formed at once, even if a finishing touch afterwards
be advisable.
CRUIKSHANK & FAIRWEATHER,
135, Buchanan Street, Glasgow,
Agents.

page_text: ་
I, EDWARD HAWKS of 41 Queen Street in the City of Edinburgh, Commission
Agent, do hereby declare the nature of this invention for SCREWS, SCREW BOLTS AND
NUTS and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:-
The main object of my invention is to obtain in screws, screw bolts and nuts all the
advantages whilst obviating the disadvantages of the two ordinary" machine threads,"
namely, the "
square thread" and the "V thread" of screws. These advantages are
obtainable, more or less, according to the purpose in view and the particular means,
or combination, selected for effecting it.
Eor Locknuts requiring great Mechanical power, great strength of thread with the
Minimum of friction, I utilise a form of thread-the buttress thread-which combines
small pitch, full base lines on bolt and nut, together with the absence of out-thrust and
its reacting friction. This thread has its working faces, like those of the square thread,
perpendicular to the axis of the screw, but it may, for some purposes and cases, be
varied by a slight "under-cut" ог over-cut even in this locknut.
"
<6
"
For this locknut, I use it preferably with its point rounded off, or slightly flattened;
and in using it or the square thread with locknuts I prefer to slit, or slot, the nut
right through at one of its angles or its sides, and preferably in a plane passing
through the axis of the screw. I thus use the locking action of the slitted &
discontinuous nut elastically with an impressure upon the bolt similar to, but with the
reverse action of, a piston ring against the cylinder.
The lock nut shown in Figure 1 shows the buttress thread, and the figure represents
a full size ordinary fish plate bolt as improved by this invention. B is the pattern
bolt, N the nut, Th the buttress thread, and S, S, and S³, also S³ & S show the slit.
The form of the slit, as seen at S³ & S', may be varied in any way, feasibly, to suit
the process of making or for the entrance of wedges or other forms of keys for easing
off the locking pressure, or for opening the nut. Preferably in making or threading
the bolt and nut, this is made rather small so as to grip firmly the bolt; but the grip
can be put on or increased afterwards by pressure or a stroke of a hammer, and can be
readily eased off or diminished by a wedge.
Any other method of slitting or Number or form of slots may be used. Thus the
slot, or slots, may be may be made not completely through from bottom to top, or from
top to bottom of the nut, but may stop short, say, at about three fourths, more or less,
from either or both directions. Fig. 2 shows the side and the top and Fig. 3 shows
the side and the bottom of the nut. Fig. 4 shows the slit right across and Fig. 5
shows two slits across from side to side. Figs. 6 and 7 show the slits across at the
angles, and Figs. 8, 9 & 10 show the slots as being alternately from the top and from
the bottom, as seen from the side, from the top and from the bottom. As shown in
these last three figures, a very elastic nut may be produced and probably very cheaply.
In thus giving a few of the methods of slitting in this way in using these threads,
which methods may be very diversified, I do not limit myself by those I have shown,

page_text: as these slits may be in any feasible number, size, form, or direction, or in any variety,
as to ways of using them.
In applying these improvements in screw threads and their uses in reference to the
conveyance of power in Machinery, as in the use of Screwjacks, planing Machines, &c.,
I have formed several threads in view of gaining both mechanical power and strength
of thread whilst retaining the power of lasting in wear. Fig. 11 shows a thread
whereby the power is conveyed only in one direction as in screwjacks, &c, for the lifting
screws of such. Fig. 12 shows a thread giving power mainly in one direction and
Fig. 13, or the semi-pyramid and Fig. 14 or the pyramid threads, would convey power
equally in any direction.
In order to facilitate the process of putting the threads in nuts I have devised
several ways of forming the nuts in two or more simple parts in the process of forming
which the threads may be impressed, whilst the metal is hot and soft, by machinery ;
and as the buttress and the square threads do not tend to burst the nuts, the said nut-
parts may be readily held in their places as forming a nut. I have planned several
ways of making the parts grip each other when put together, in a more or less elastic
manner. Fig. 15 is formed of two parts held together simply by a ring or washer,
where NN are the said two parts on which are formed the two semi-rings, or
projections, PP, and these are forced into the ring or washer W, either before or
during the application of the nut into use. PP are formed with a slight taper or
"draw" and may be "overset" on getting through the washer W. This fastening
may be formed at either (or both) the top or bottom of the nut.
Figs. 16 and 17 show a method by which the two nut-parts grip each other by a
mutual interlocking process, at the sides in Fig. 16 and at the angles in Fig. 17, as
shown. NN indicate the nut-parts, and P P the projections or catches. Many other
methods similarly effective I have devised, of which thoso given show how it is
done.
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 :-
1st Screw nuts screwed and cut substantially in the manner and for the purposes
specified.
2nd Machinery screw threads formed substantially in the manner and for the
purposes specified.
3rd Screw nuts formed in parts and screwed substantially in the manner and for
the
purposes specified.
EDWARD HAWKS.