IMPROVEMENTS IN JOURNAL BEARINGS, AND IN THEREIN AND OF ANTI-FRICTION COMPOSITIONS FOR USE IN OTHER PARTS MACHINERY
Year: 1880

page_text: PROVISIONAL SPECIFICATION left by Alexander Melville Clark at the
Office of the Commissioners of Patents on the 8th September 1880.
A communication from abroad by Hiram Gustavus Farr and Henry Clay
Copeland, both of Brandon in the County of Rutland and State of Vermont,
United States of America.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of
Middlesex, Patent Agent. "IMPROVEMENTS IN JOURNAL BEARINGS, AND IN
THEREIN
AND
OF
ANTI-FRICTION COMPOSITIONS FOR USE
IN OTHER PARTS
MACHINERY." [A communication from abroad by Hiram Gustavus Farr and
Henry Clay Copeland, both of Brandon, in the County of Rutland and State of
Vermont, United States of America.]
This Invention relates to that class of journal bearings in which provision is made
for the retention therein of solid or plastic lubricating material, but which may
also contain porous solid substances for retaining liquid lubricating materials by
their capillary action.
The Invention consists, first, in a journal bearing having a groove or grooves
formed in its internal or bearing surface, said groove or grooves being inclined to
the longitudinal axis of the said bearing. The said journal bearing may be made
in halves as usual or in a single piece. The Invention consists, secondly, in an
anti-friction composition composed of plumbago or graphite and shellac which has
superior qualities for lining the bearings of machinery.
Figures 1 and 2 in the Drawings represent respectively halves of a journal
bearing which is formed by casting in a single piece. Figures 3 and 4 represent
respectively the two halves of the core-box employed to form the core for casting
the said bearing, and which will be referred to in the description of the saine.
Figures 5 and 6 represent respectively halves of a journal bearing formed in a
single piece in a modified way of carrying out the Invention. Figures 7 and 8
represent respectively the two halves of the core box used to make the core for
casting the bearing shown in Figures 5 and 6. Figures 9 and 10 show the
composition formed as lining for a bearing.
The halves represented in Figures 1 and 2, 5 and 6 are such as would be formed
by a section through the bearings at right angles with the plane on which its proper
core-box divides to draw the core from the said box. In Figures 1 and 2 there are
one or more spiral grooves extending the entire length of the bearing, and somewhat

page_text: resembling screwthreads. They are not screwthreads however, their form being
similar to that of the grooves in the core box C, Figures 3 and 4. The form of
these latter grooves is such that the core may be drawn from the core box.
D represents the part of the core box that forms the core prints. e represents plane
sided grooves in the core box to form projections on the core for the formation of
the grooves b in the bearing (Figures 1 and 2), and ƒ represents the parts
intervening,
The sides of the grooves e in the said halves of the core box are planes inclined
to the longitudinal axis of said box. This form of the grooves enables the core
to be drawn from the core box, which could not be done with a regular screwthread. 1
In the modification shown in Figures 5 and 6, the grooves do not extend the whole
length of the bearing but are formed obliquely to the central longitudinal axis of
the bearing, a central section through any of the said grooves parallel to the side
thereof being an ellipse baving dimensions the same as if formed by cutting a
cylinder of the same diameter as the shortest diameter of the said ellipse by a plane
inclined to the longitudinal axis of the said cylinder in the same angle. The
said bearing is cast in one piece over a core made in a core-box C' (Figures 7 and 8),
in which D represents the core prints. e¹ represents the grooves of the said core-
box which form the projections on the core over which the said grooves are cast,
and f¹ the intervening parts.
It will be seen that the two core boxes C and C¹
are similar, except that in the core box C the grooves e appear inclined in the same
direction in both halves of the said core box when separated and opened as shown,
and that in the core box C¹ the grooves e¹ appear inclined in opposite directions in
the two halves of the said core box when the same are separated and placed
as shown.
The core box C forms a core for the casting of a groove that will extend the
whole length of the bearing, and the core box C' forms a core for the casting of the
parallel inclined grooves b' shown in Figures 5 and 6. The common feature of the
grooves in both the forms of the bearings shown and described, is that the sides of
the said grooves are plane surfaces or made up of plane surfaces inclined to the
longitudinal axis of the bearing. In the said grooves is placed the plastic or solid
lubricating material or a porous substance for holding a liquid lubricating material,
as shown at g, Figures 1, 2, 5, and G.
By this construction of the bearing I am able to support a journal on metal at
the bottom and at all parts of its periphery, that is to say, there is no line in the
bearing surface parallel to the axis of the said journal that can at any time bear
wholly against or upon a surface of lubricating material. Every part of the surface
of the journal must pass over aud be lubricated by the said lubricating material at
each revolution of the said journal. The form of the said grooves is moreover
well suited to holding any solid or plastic lubricating material. Moreover the said
inclined position of the groove or grooves relatively to the axis of revolution of
the shaft or the journal in said bearing acts to carry or force dirt out of or off from
the said bearing surface.
°
In preparing the composition I generally take about 75% by weight of plumbago
or graphite, and about 25% by weight of shellac. We preferably first dissolve the
sheilac in a sufficient quantity of alcohol, say, about two pounds of shellac to about
three pints of alcohol, and after reducing the plumbago or graphite to a fine powder
it is introduced and stirred into the shellac solution to form a composition of dough
like consistency. After thoroughly commingling the plumbago and shellac, the
composition may be spread on a board or other surface and dried by exposure to
the utmosphere, or in an oven, and is afterwards preferably ground to a fine powder
in any suitable mill.
To form the composition into the desired articles, it may be taken either in lumps
or masses of suitable size, or preferably pulverized as above described, and placed in
a mould of the proper size and shape, heated by steam or otherwise to a temperature
of, say, 200° to 600° F., and when thus heated the composition may be pressed into
the grooves of the box. The high degree of heat softens the shellac, and its adhesive

page_text: qualities bind the particles of graphite together and form a hard and tough
composition.
Instead of dissolving the shellac in alcohol it may be fused by a heat of
about 250 F., and plumbago or graphite introduced and thoroughly commingled
therewith by stirring or otherwise. In such case however it is not practicable to use
so large a porportion of plumbago as when the shellac is first dissolved in alcohol.
When so prepared the mixture is preferably dried and ground to powder as
previously described, but it may be introduced into the heated moulds in lumps or
inasses of suitable size and the grinding dispensed with. Bushings or linings of
this composition may be used for loose pulleys, bearings, axle boxes, spindle
bolsters, steps, &c. The composition may also be moulded into sheets and
used for flat bearings, such as guides for steam engines and other machinery.
Although this composition is preferably molded while hot and plastic, it might be
worked into the desired shape from solid masses when cold.
The proportions of shellac and graphite or plumbago above-mentioned, are those
which experiments have shown to give the best results, but they may be varied
without materially changing the character of the composition. By the use of
shellac with plumbago or graphite, I have found by actual experiments that the
shellac imparts an important quality to the compound, viz., it renders the
composition more durable and capable of resisting greater pressure without liability
of disintegrating, and further the compound is rendered more plastic when hot
than where made with gum copal and is harder when cold.