IMPROVEMENTS CONNECTED WITH SCREW BOLTS, SCREW SPINDLES, AXLES, AND LIKE ARTICLES, AND THEIR NUTS, TO PREVENT THE NUTS WORKING LOOSE FROM VIBRATIONS AND CONCUSSIONS
Year: 1877

page_text: LETTERS PATENT to Thomas James Smith, of the Firm of Robertson, Brooman,
and Company, of 166, Fleet Street, in the City of London, Patent Agents, for
the Invention of "IMPROVEMENTS CONNECTED WITH SCREW BOLTS, SCREW
SPINDLES, AXLES, AND LIKE ARTICLES, AND THEIR NUTS, TO PREVENT THE NUTS
WORKING LOOSE FROM VIBRATIONS AND CONCUSSIONS." A communication
from abroad by Emile Monnier, of Rue des Halles, Paris, France.
Sealed the 29th January 1878, and dated the 9th August 1877.
PROVISIONAL SPECIFICATION left by the said Francis James Smith at the
Office of the Commissioners of Patents on the 9th August 1877.
THOMAS JAMES SMITH, of the Firm of Robertson, Brooman, and Company, of 166,
Fleet Street, in the City of London, Patent Agents. "IMPROVEMENTS CONNECTED
WITH SCREW BOLTS, SCREW SPINDLES, AXLES, AND LIKE ARTICLES, AND THEIR NUTS,.
TO PREVENT THE NUTS WORKING LOOSE FROM VIBRATIONS AND CONCUSSIONS.'
(A communication from abroad by Emile Monnier, of Rue des Halles, Paris,
France.)
"
This Invention relates to improvements connected with screw bolts, screw
spindles, axles, and like articles, and their nuts, to prevent the nuts working loose
from vibrations and concussions, and consists mainly in forming a screw thread
upon a nut of a different pitch to the thread within the nut, in order that the nut
itself may receive a second nut upon its exterior, by which the first-named nut is.
prevented turning back after it has been tightened up, and the second nut tightened
up upon it. The two threads of the first-named nut may have right-handed screw
threads, or one may be right-handed and one left-handed, as desired.
In some cases the first-named nut may have two distinct pitched threads formed
upon its exterior upon different diameters, or the bolt, spindle, axle, or other like
article may have screw threads of different pitches, but both right-handed or both
left-handed upon different diameters for separate nuts to be screwed upon them, or.
the head of a bolt may be screw-threaded for a correspondingly threaded nut to

page_text: engage upon, in order that this when tightened up shall prevent the bolt working
loose from any cause. The second nut may have a third threaded nut screwed
upon.it.
Many modifications of single or double threaded nuts and of single or double
threaded bolts, axles, or spindles may be adopted, and in some cases discs or ring
washers may be used in combination, the object being to dispense with keys, wedges,
pins, and other like appliances now usually employed for the purpose.
The Invention is applicable to bolts and screw fasteners of all classes or kinds
of machinery, structures, as well as to spindles, coach axles, and the like.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Thomas James Smith in the Great Seal Patent Office on the 9th
February 1878.
"
THOMAS JAMES SMITH, of the Firm of Robertson, Brooman, and Company, of 166,
Fleet Street, in the City of London, Patent Agents. IMPROVEMENTS CONNECTED
WITH SCREW BOLTS, SCREW SPINDLES, AXLES, AND LIKE ARTICLES, AND THEIR NUTS,
TO PREVENT THE NUTS WORKING LOOSE FROM VIBRATIONS AND CONCUSSIONS."
(A communication from abroad by Emile Monnier, of Rue des Halles, Paris,
France.)
This Invention has for object improvements connected with the various modes of
tightening or fastening, and specially to the parts of machines known as nuts, and
by extension to other similar parts formed of various joints, as, for example, to
keying..
The Invention consists not only in ensuring the tightening of a nut screw, bolt,
or similar article, by one or several nuts, with threads of equal or different pitch
in the same or contrary direction, and concentric to the first, but also to ensure
the same tightening by an application of the same principle by nute screwed on
one after the other, having threads in the same or contrary direction, preferably of
the same direction, but of different pitches, so as to produce a tightening by a
differential movement. This same principle is applicable to cotters, of which the
inclined faces may be likened to the upper faces of screw threads or spirals in
profile.
To better understand in what my improvements consist, they will be explained in
regard to the annexed Drawings, in which are shown as examples a few of the
numerous applications and combinations which may be realized by the means
described.
Figures 1 and 2 represent two parts K, H, tightened by a nut M against a bolt
head V, which nut itself carries another nut P, for which the said nut M serves as
a screw, a part of its length being screw threaded for that purpose. The combina-
tion of the screw nut M and the nut P constitutes the "Monnier nut."
In Figure 1 the nut P should be screwed on the nut M before the screwing of the
latter on to the bolt V, but in Figure 2 the nut P may be screwed on after tight-
ening the screw nut M.
The following is the mode of operation for tightening the parts K, H, against the
bolt head by the "Monnier nut," as shown in Figure 2; the nut M is first screwed

page_text: on to ensure the suitable adjustment of the two parts K, H, after which the nut P
is screwed on. If extra tightening is desired it can be obtained without fear of
breaking the bolt by holding the nut M with a key whilst tightening the nut P so
as to avoid the twisting effort on the bolt.
"
Figure 3 represents a threaded bolt V carrying an ordinary nut I, and on which
bolt is screwed the "Monnier nut," as just described. During the tightening of the
Monnier nut" the nut I is kept fixed by the aid of a key. This system is
available for numerous useful applications.
Figure 4 represents a part K fastened against another part H by a screw bolt O.
The part K serves as a fixed nut; it is tightened or pressed against the part H by
the screw head O. The screw head O is threaded for a part of its length, and carries
a nut P. The stem of the screw head O is first screwed into the part K to ensure
its adjustment against the part H, after which the tightening is completed by the
nut P.
.
Figure 5 represents two parts K, H, tightened against a bolt head V by two nuts
C and D. The shank or stem of the bolt has two different diameters, that of the
opposite end to the head is the smaller; the shank also carries two threads of
different pitch; the smaller diameter thread is also less in pitch. On each of the
threads is screwed a nut, the nut C on the larger pitch, and D on the other. The
nut on the larger diameter may for special applications have the lesser pitch.
Figure 6 represents a gudgeon G, screwed into a part H. It is kept fixed and
immovable by the nut P, screwed against the part H (this being one application of
Figure 4). The nut P may be sunk into the part H.
Figures 7 and 8 represent two screws V. In Figure 7 the screw V can be turned
in its place; its head O carries (as in Figure 4) a nut R, the tightening of which on
the cross piece T immovably fixes the position desired to be given to the wedge E.
In Figure 8 the screw V screws into the threaded cross piece T, drawing up or repel-
ling the wedge E. The position of the wedge E is fixed by fixing that of the screw
by the aid of the "Monnier nut," that is to say, by first tightening the nut M on to
the cross piece T, then the nut P.
Figure 9 represents a side view; and 10 and 11, two vertical sections through the.
line A, B, of Figure 9, of ends, connecting rods carrying two screw breaks C and I for
the key R. In Figure 10 the two screw breaks are thicker in the upper part;
in Figure 11 the break I is of equal thickness for the whole of its length.
The screw breaks are fastened on a bolt g by the "Monnier nut," shown in
Figure 1; they may also be fastened by the two nuts shown in Figure 5. The
washers are of unequal thickness to ensure equal pressure of the bolt head and of
the nut in contact. The ends of the screw breaks may or may not carry a flange 8.
Figures 12 and 13 represent a part side elevation and end view of a connecting
rod end of which the brasses are secured by the "Monnier nut" by the aid of a cross
piece T.
Figures 14 and 15 show the vertical section and end view of an ordinary stuffing
box of a steam cylinder of a locomotive, on the gland studs of which the "Monnier
nut" shown in Figure 3 is shown applied.
Figures 16 and 18 show the vertical section and end view of the application of
the "Monnier nut to a circular stuffing box of a locomotive steam cylinder.
"
Figure 17 represents the ring 8. M is a socket which has on its exterior two
threaded portions of unequal pitch. It is screwed in the interior of cylinder,
threaded for that purpose to produce the tightening of the ring S on the packing.
The larger pitch receives a nut P, which serves as a lock nut, and which is screwed
against the cylinder to ensure any required position of the socket M. The ring S
carries a snug v, which guides it in the groove r, parallel to the axis x.
Figures 19, 20, 21, 22, and 23 show applications of the "Monnier" system of nuts,
shown in Figures 1, 3, and 5, to coach axle boxes for securing the ring B. In Figure
22 the two systems shown in Figures 1 and 3 are combined. The nuts C, P, D,
represent nuts with flanges; the right of giving them any other shape is reserved..
In each of these Figures the cap or crown L carries a nut A for ensuring its position,

page_text: and the latter has a flange which forms a joint on the box Z by the aid of packing.
In Figure 23 the screwing of the nut P is operated by unscrewing the nut M, when
the flat part of the nut P is parallel to the stop y of the ring bearing, and opposite
this bearing. The ring B bears on thin washers o, destined to be removed, as the
play between the box Z and the ring B necessitates the tightening of this latter.
These washers may be adopted in the other Figures.
Figure 24 is an arrangement in which, by the aid of the application of the
"Monnier " nut a great pressure may be produced. The cross piece S is a fixture.
The fly wheel O, acting on the head of the screw V, causes it to rapidly advance
until contact; then by acting on the nut M by the fly wheel N, the nut P advances
with a differential movement proportionate to the difference of the two pitches of
P, M, and M, V; an extremely great pressure may thus be produced.
Figure 24 represents a similar application to the preceding of the "Monnier
nut" to produce the same amount of pressure with a minimum force, the screw being
embedded in the base H. The pitch of the screw V kept fixed by the bearing D
is greater than that of the nut P. The two threads are right-handed, but they may
be either right or left handed. The nut P maintained in position by the guides C
cannot turn and act as a nut screw. By each turn to the right of the nut M the
base 7, 8, of the nut P diminishes its distance from the fixed base H, in which the
screw V is embedded; equal to the difference of the two pitches. The pressure thus
obtained is therefore considerable.
K.
Figure 25 shows a round stem or shank T, threaded for a part of its length at V,
and terminated at the opposite part by a square end with a threaded prolongation
The square part J receives a cross piece A, fastened on the stem by the
"Monnier nut." The threaded part V carries a "Monnier nut," of which the two
threads are right-handed and the interior thread is of coarser pitch than the other.
The socket S,
The nut P, by the aid of two guides C, also acts as a nut screw.
threaded on the exterior, is turned on the shank T by the fly wheel B; it ascends or
descends, (supposing it to be arranged vertically) in the fixed cross piece R, which acts
The screw of this socket may be of one or several threads, according to
circumstances; it may also be right or left handed. The cross piece A. carries two
guide rods G, which prevents the stem T turning, impelled by the movements of S.
The nut head M carries a fly or other lever N, if necessary.
as a nut.
When it is required to exert a pressure a screwing movement is imparted to the
fly B (that is to say, that it is turned to the right when the thread is right handed,
and vice versa), which causes the whole system to descend rapidly until Y, Z, is in
contact with the surface to be pressed upon, after which the fly N, and consequently
the nut M is tightened. By slightly unscrewing the fly N, and turning quickly the
fly B in the direction of unscrewing, the surface Y, Z, is rapidly removed.
All the modifications possible with this system are reserved; the threads may be
in the same or contrary directions; the shape, the sizes, the number, and pitch of
the threads may all be varied according to circumstances.
Figures 26, 27, and 28 represent various applications of the same differential
system applied to a keying arrangement known as "Monnier keys," reposing on
various combinations of several planes differentially inclined for the object of obtaining
a sure fastening. These inclined planes, considered as the development of threads of
different pitch, which are the bases of the two systems of "Monnier nuts," are on
the same principle and produce analogous results. They are like the "Monnier nut,"
susceptible of different modifications and applications, according to circumstances.
In Figure 26 the keys P, M, are connected to a piece H, and they bear one face of
M upon this piece H, and one face of P against the end of a slot formed on, say, a
stem of a rod or stay. The directions of the two inclined planes r, u, and f, g, are
for , u, of the exterior screw thread, and for f, g, of the interior screw thread of a
Monnier nut" (Figure 1 for example).
"
Figure 27 represents the assemblage of the three keys I, M, P, through a rod or
stay, without further support than being tightened against the end faces of the
mortise or slot, as shown, in which they are assembled. Thus joined together they

page_text: form a fixed and immovable seating. This assemblage is the reproduction by the
aid of keys of that of the three nuts, Figure 3 producing an analogous effect, and
reposing on the same principles.
Figure 28 represents a fastening of the bearings of a connecting rod, for example,
by the two keys M, P. The tightening is made on a cross piece H, which transmits
it to the bearing. Like the screw threads of which they are the developements, the
inclined planes of the "Monnier" keys may, together or separately, vary in inclina-
tion either in their direction or their size.
The various arrangements just described are only for the purpose of showing the
generality of applications, of which the principle of differential travel is susceptible,
such as fastening nuts and keys to the application of screws, stuffing boxes, con-
necting rod ends, railway breaks, manual as well as hydraulic presses, coach axle
boxes. The effects produced by vibration and concussion on straight or unequally
inclined planes are avoided by this system, they remaining fixed and immovable,
besides the extra pressure obtainable.
Any material may be employed, also any shapes, sizes, and combinations, pro-
viding the fundamental principle of the system is applied.
And having now-described the nature of the said Invention, and in what manner
the same is to be performed, I declare that I claim,—-
First. The system of screwing and fixing obtained by the application of the
principle of differential travel in the direction of the screwing by means of screw
threads of same or contrary direction, but of different pitch or different inclination,
as set forth, and substantially as shown in the annexed Drawing.
Secondly. I claim all the applications of which this system of screwing or pres-
sure is susceptible, either to railway or navigation material, to general mechanical
industry, as nuts, bolts, keys, screws, gudgeons, stuffing boxes, presses of all descrip-
tions, railway breaks, and analogous applications.
In witness whereof, I, the said Thomas James Smith, have hereunto set my
hand and seal, this Eighth day of February, One thousand eight hundred
and seventy-eight.
T. J. SMITH. (L.S.)