IMPROVEMENTS IN COG WHEELS, LOOSE FOR DESTROYING PULLEYS, ROLLERS, AND REVOLVING BODIES VIBRATION
Year: 1880

page_text: LETTERS PATENT to Augustus Bryant Childs, of No. 70, Fenchurch Street,
"
OTHER
London, for an Invention of IMPROVEMENTS IN COG WHEELS, LOOSE
FOR DESTROYING
PULLEYS, ROLLERS, AND
REVOLVING BODIES
VIBRATION." A communication from abroad by Friedrich Wegmann, of
Zurich, Switzerland.
PROVISIONAL SPECIFICATION left by the said Augustus Bryant Childs at
the Office of the Commissioners of Patents on the 29th September 1880.
"IMPROVE-
AUGUSTUS BRYANT CHILDS, of No. 70, Fenchurch Street, London.
MENTS IN COG WHEELS, LOOSE PULLEYS, ROLLERS, AND OTHER REVOLVING
BODIES FOR DESTROYING VIBRATION." A communication from abroad by
Friedrich Wegmann, of Zurich, Switzerland.
The object of my improvement is to prevent the noise or jar usually resulting
from the rotation of bodies used in machinery, more particularly where they work
against or into each other, such as cog or gear wheels for working porcelain or
metal roller mills, and for other purposes. My improvement is also capable of
counterbalancing rotating bodies, such as loose pulleys, fly wheels, millstones, and
similar bodies, and thereby cause the smooth working of the whole machine.
The usual noise resulting from machinery in motion is caused by the vibration of
hard parts acting on or working against each other, such as cog wheels, loose
pulleys, fly wheels, and similar parts. The noise may be prevented or greatly
reduced by causing a loose body of sand, shot, or other hard substance made small
enough to flow or shift in a hollow or annular space made in the rim of the cog
wheel or revolving body; this space should be as near the circumference of
the rotating body as practical, and by thus supplying it with a hard shifting
substance the vibration of the parts is prevented, on the well known principle in
acoustics that if a vibrating body is touched while in motion by any hard substance
the vibration is destroyed, and consequently the jar and noise it produces.
Instead of using sand, shot, or other hard substances reduced to make them move
or shift freely, liquids may be employed, such as mercury, for preventing the
vibration and deadening the noise.

page_text: It will be more practical, cheaper, and better to cast the annular space in gear
wheels, pulleys, and other rotating objects to receive the sand, shot, or shifting or
moving substance; however, they can be made by attaching plates to the side of
gear and other wheels, and bolted thereto, to form the required annular space; or
an annular pipe of any desired transverse sectional form may be attached to gear
wheels, pulleys, fly wheels, millstones, or any other rotating body to which it may
be desired to apply the improvement; but the mere idea of forming annular or
hollow spaces around the rims of cog wheels, pulleys, fly wheels, and other objects
is not new, and such annular or hollow spaces may be made in any convenient
manner, and to suit the piece of mechanism to which the improvement is applied.
By filling such annular spaces with small hard shifting substances, as before
mentioned, it not only deadens the noise, but at the same time causes the whole
machine to work more steady and smooth.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Augustus Bryant Childs in the Great Seal Patent Office on the
23rd March 1881.
AUGUSTUS BRYANT CHILDS, of No, 70, Fenchurch Street, London. "IMPROVE-
MENTS IN COG WHEELS, LOOSE PULLEYS, ROLLERS, AND OTHER REVOLVING
BODIES FOR DESTROYING THE VIBRATION." A communication from abroad by
Friedrich Wegmann, of Zurich, Switzerland.
The object of my improvement is to prevent the noise or jar usually resulting
from the rotation of bodies used in machinery, more particularly where they work
against or into one another, such as cog or gear wheels for working porcelain or
metal roller mills, and for other purposes. My improvement is also capable of
counterbalancing rotating bodies, such as loose pulleys, fly wheels, millstones, and
similar bodies, and thereby cause the smooth working of the whole machine. The
usual noise resulting from machinery in motion is caused by the vibration of hard
parts acting on or working against each other, such as cog wheels, loose pulleys,
and similar parts. This noise may be prevented or greatly reduced by causing a
loose body of sand, shot, or other hard substance made small enough to flow or shift
in a hollow or annular space made in the rim of the cog wheel or revolving body;
this space should be left as near the circumference of the rotating body as practical,
and by thus supplying it with a hard shifting substance the vibration of the parts
are prevented, on the well known principle in acoustics that if a vibrating body is
touched while in motion by any hard substance the vibration is destroyed, and
consequently the jar and noise it produces. Instead of using sand, shot, or other
hard substance reduced to make them move or shift freely, liquids may be employed,
such as mercury, for preventing the vibration and deadening the sound. It will be
more practical, cheaper, and better to cast the annular space in gear wheels, pulleys,
and other rotating objects to receive the sand, shot, or shifting or moving substances;
however, they can be made by attaching plates to the sides of gear and other wheels,
and bolted thereto, to form the required annular space; or an annular pipe of any
desired transverse sectional form may be attached to gear wheels, pulleys, fly wheels,
millstones, and any other rotating body to which it may be desired to apply the
improvement; but the mere idea of forming annular or hollow spaces around the
rims of cogwheels, pulleys, flywheels, and other objects is not new, and such
annular or hollow spaces, may be made in any convenient manner, and to suit the
piece of mechanism to which the improvement is applied
By filling such annular spaces with small hard shifting substances, as before
mentioned, it not only deadens the noise, but at the same time causes the whole
machine to work more steady and smooth.
The usual noise from machinery in motion is caused by the resonant vibration of
the metallic portions which are acting or working upon each other, such as cog
wheels, loose pulleys, rollers, &c., &c. The application of elastic cushions is known
to modify or neutralize these sonorous vibrations so as to mitigate or prevent the
noise, but hitherto no application of this sort has been made in connection with
revolving machinery, and therefore the object of my Invention is to modify or
neutralize the sonorous vibrations in wheels of all kinds by applying elastic or non-
sonorous bodies to interior parts of said wheels to prevent the propagation of said
vibrations. This effect is well known in acoustics. The deadening substances may
be solid or fluid, and if solid it is preferably in a comminuted form and loosely
distributed.
That others may fully understand my improvement I will particularly describe
the same, having reference to the accompanying Drawings, wherein Figs. 1, 2,
and 3 show in plan and central transverse section wheels embracing my improve-
ment. The wheel A may be understood to represent any description of revolving

page_text: cylindrical structures, such as is designated by the generic word wheel, notwith-
standing for convenience the wheels are represented with peripheral teeth or cogs.
The wheel A is provided with a solid rim b and an interior annular cavity d, a
solid hub e, and an intermediate web or set of arms g, as usual.
Within the annular cavity d the deadening substance is placed in a free condition.
I think sand is, all things considered, a preferable substance, although shot or liquids
may be employed if preferred.
This annular cavity may be formed in any appropriate way known to the arts,
such as by a core set in the mould, as represented by wheel B, Fig. 1, or by joining
plates a secured by screw bolts f to the wheel, as represented in Fig. 3. Three
different modes of structure are shown in the Drawings, and others will occur to any
skilled constructor in the art. When a wheel which is provided with an annular
chamber d is charged with a movable mass or charge distributes itself over the
exterior periphery surface of said chamber, and absorbs the vibrations of the metallic
parts of the wheel in contact with said mass. Another and incidental advantage is
due to the automatic distribution of the charge, that is to say, the distribution of
the movable mass or charge will be with reference to the centre of revolution and a
centre of gravity coincident therewith. The wheel will be thereby balanced auto-
matically. This Invention may be applied.to wheels already in use or constructed
by means of a hollow ring, which may be bolted to the side or within the
periphery.
'
1
1
:
Having described the nature of my Invention and its mode of action, what I
claim as new.is,,—
1st. A wheel provided with a hollow rim. or annular chamber concentric to the
hub, combined with a mass of non-resont granular substance within said chamber,
free to distribute itself therein, as and for the purpose set forth.
+
2nd. The, mode or method of absorbing sonorous vibrations and noise in
revolving wheels, which consists essentially in placing within a cavity or cavities
in said wheel loose masses of solid or fluid non resonant substances, substantially as
described..
'
3rd. A wheel provided with one or more cavities interior as to the rim, combined
with a non-resonant substance placed loosely in said cavity or cavities, and partly
filling the same, as set forth.
4th. A wheel constructed with a peripheral groove d combined with an annular
rim fitted to cover and close said groove, and a non-resonant substance placed
loosely in the chamber formed by said groove and rim, and partly filling the
same.
In witness whereof, I, the said Augustus Bryant Childs, have hereunto set
my hand and seal, this 16th day of March, in the year of our Lord
1001
AUGUSTUS BRYANT CHILDS. (L.S.)