Improvements in Composition Bearings and Process of Manufacturing the same.
Year: 1892

page_text: Date of Application. 31st May, 1892-Accepted, 3rd Sept., 1892
COMPLETE SPECIFICATION.
Improvements in Composition Bearings and Process of Manufacturing
the same.
I HENRY HOWSON, Patent Attorney of 119 South 4th Street in the City of
Philadelphia State of Pennsylvania United States of America do hereby declare
the nature of this invention and in what manner the same is to be performed to
be particularly described and ascertained in and by the following statement :-
The object of my invention is to form bearings of lubricating material and
binding material compressed into form which bearings will effectually withstand
severe strains and shocks, the said bearings being especially adapted for car axle
journals, stamping machine journals, and for bearings generally which are subjected
to pressure, and also subjected to severe shocks and strains.
The compound I prefer to use in carrying out my invention is a mixture of fibre
(such as divided wood fibre) and plumbago, combined with a suitable binder,
preferably a drying oil or semi-drying oil which will be resinified by the action of
heat, to which the bearing is subjected during its manufacture, but it will be
understood that materials other than those mentioned, may be used for instance,
soapstone can be substituted for plumbago, and other fibres may be substituted for
divided wood fibre, and any of the well known fluid binders may be used in place of
the resinified oil binder.
In the accompanying drawing:-
-
Figure 1 is a sectional view of the mould, illustrating my improved process of
manufacturing composition bearings;
Figure 2 is a longitudinal sectional view of the moulded bearing;
Figure 3 is a transverse sectional view.
66
In this Specification I will refer to the plumbago, soapstone or equivalent
material, employed as "lubricating material" and to the fibre or other material
which will act as a support for the lubricating material as supporting material."
I will now describe my process in connection with the employment of fibre
and plumbago and an oil binder, as the best results are obtained by using those
materials.
The plumbago is mixed with finely divided fibre by stirring it with the fibre, in
a liquid solution, simply using water. I preferably make several batches of this
material, one batch in which the proportion of plumbago to fibre is very great; in
fact, in some instances, the plumbago may be in a pure state. The next batch
may have a greater proportion of fibre to plumbago; the next batch may have
the plumbago and fibre in the same proportion, and the fourth batch may have the
fibre in excess of plumbago, and the fifth, or last batch, may be all fibre.
I first place in the mould a layer a of fibre, then I place upon this a layer b of a
compound consisting of fibre and plumbago, in which the fibre is in excess, then
next to this I place a layer c of material in which the plumbago and fibre are of
equal parts, and upon this I place a layer d, in which the portion of plumbago is in
excess of the fibre, and upon the latter I place a final layer of either pure plumbago,
or plumbago with a small quantity of fibre.
In the bottom of the mould A is the drainage plate B, and in one end of the
mould is a plunger D, and closing the mould is a cap E, secured to the body A in
any suitable manner.
When the body of the mould is filled, as described, the cap E is placed in
position, and the plunger is forced into the mould, compressing the material therein
to the density required, the liquid escaping from the material through the perforated
plate B the supporting material acting as a filter preventing the escape of the
lubricating material from the mould. When fibre is used, (which is the preferred

page_text: material, for use as a supporting medium,) the fibre of one layer will become
entangled with the fibre of another layer, as the liquid has a tendency to carry
the fibre with it and as the liquid passes through one layer to another and to
the outlet, the fibres will tie the several layers together and the pressure of the
plunger has also a tendency to turn the fibres parallel with its face consequently,
the several sections become interlocked under the heavy pressure, and a bearing is
made in a coherent mass, having a greater proportion of lubricating material at
the face, than at the back, and having also a greater proportion, by preference, of
supporting material than of lubricating material at the back. I have described
a bearing made from five layers of material, but it will be understood that it can
be made from two or more layers, depending upon the work for which the bearing
is intended, and the thickness of the bearing.
After the mass has been pressed and dried it is then saturated with a suitable
liquid binder, and I prefer to use a drying or a semi-drying oil for this purpose.
After the saturation, the bearing is subjected to a heat sufficient to set and
solidify it.
I am thus enabled to produce a bearing having a good lubricating surface,
supported and strengthened by the backing formed of fibre, which is, however,
a part of the bearing, and is so intimately mixed with the plumbago and fibre at
the bearing surface, that any severe strains or shocks which would, under ordinary
circumstances, crack and destroy the bearing will be taken up and sustained by the
backing of fibre, the latter being tough and strong and possessing a certain amount
of elasticity.
In some instances, the order in which the layers are placed in the mould
may be reversed, the plumbago being placed in the mould first, and the backing
fibre last.
By the term bearing, as I use it, is meant any machine element or structure
which is subjected to friction, and it will be understood while I have shewn
simply, one form of mould for carrying my invention into effect, other moulds
may be used, and the bearing may be shaped differently from the bearings
shewn in Figures 2 and 3, these views being simply given to illustrate one form
of bearing.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
First.-A bearing composed of a lubricating material and a supporting material
moulded and united, the proportion of lubricating material to supporting material
being greater at the face of the bearing than at the back, substantially as
hereinbefore specified.
Second. A bearing composed of plumbago and fibre, compressed and united,
the proportion of plumbago to fibre being greater at the face of the bearing than
at the back, substantially as hereinbefore described.
Third. A bearing composed of plumbago and fibre, compressed and united, and
having at the bearing face an excess of plumbago, and at the rear an excess of fibre,
substantially as hereinbefore described.
Fourth. A bearing composed of lubricating material and fibre, compressed and
united, the lubricating material being in excess at the bearing face, and the fibre
in excess at the rear, and the fibres lying transversely to the line of the bearing
face, so as to tie the bearing together transversely, substantially as hereinbefore
described.
Fifth. The process herein described of manufacturing bearings, the said process
consisting in placing in a mould two or more layers of material, one of the said
layers having a greater proportion of lubricating material than the other,
compressing the material in the mould to form a solid, homogeneous mass, in which
the proportion of lubricating material to sustaining material is greater at the face
than at the back, substantially as hereinbefore described.

page_text: Sixth. The process herein described of manufacturing bearings said process
consisting in placing in a mould two or more layers of material, one of the said
layers having a greater proportion of supporting material than the other,
compressing the material in the mould, so that the supporting material at the
back of the bearing will act as a filter and prevent the escape of the lubri-
cating material during the compression of the mass, substantially as hereinbefore
specified.
Seventh. The process herein described of manufacturing composition bearings,
the process consisting in first, placing in a mould a series of layers of lubricating
and supporting material in a semi-fluid state, compressing the material in the mould
so as to unite the layers and to remove the liquid, drying the composition thus
formed, impregnating the mass with a fluid binder, drying the composition, so as to
set, solidify and harden the mass, substantially as described.
Eighth. The process herein described of manufacturing composition bearings,
the said process consisting in first placing a series of layers of fibre and a
lubricating material, such as plumbago, in a mould, securing the composition in
the mould and subjecting the composition to an end pressure, so as to make the
fibres in one layer entangle with the fibres of the adjoining layer or layers to form
a solid homogeneous mass, substantially as hereinbefore described.
Deted this 21st dos of Mar 1909
J. H. JOHNSON & Co.,
Agents.