Improved Composition of Matter suitable for use in the Manufacture of Journal Bearings, Packings, Projectile Rings, Commutator Brushes, and various other articles where Surfaces come into Frictional Contact, and for Conductors of Electricity.
Year: 1892

page_text: COMPLETE SPECIFICATION.
Improved Composition of Matter suitable for use in the Manufacture
of Journal Bearings, Packings, Projectile Rings, Commutator
Brushes, and various other articles where Surfaces come into
Frictional Contact, and for Conductors of Electricity.
I PHILIP HENRY HOLMES of Gardiner Kennebec County Maine, in the United
States of America Mechanical Engineer do hereby declare the nature of my inven-
tion and in what manner the same is to be performed to be particularly described
and ascertained in and by the following statement :-
The
My invention relates to an improved composition of matter adapted for the
manufacture of journal bearings, packing, projectile rings, commutator brushes,
and various other articles where surfaces come into frictional contact.
composition of matter can also be used as a conductor of electricity as hereinafter
fully described.
In carrying my invention into effect, I preferably take plumbago in a finely
divided form, and floated, so as to obtain it as pure as possible, this I mix with
fibre, preferably in a finely divided state. In order to thoroughly mix these two
substances, I first mix the fibre with water, or other liquid and then add the
plumbago, so as to form a semi-fluid mass. The relative proportions of plumbago
and fibre may vary, depending upon the character of the article to be produced,
but in the majority of cases, the plumbago is in excess. This is especially so when
the material is used as a bearing, in order to obtain the most efficient lubricating
effect consistent with strength.
For bearings, I can use proportions varying from four to thirty-five parts by
weight of plumbago to one part by weight of fibre. These proportions may be
varied however, and still insure good results.
The material, when thoroughly mixed, as before stated is placed in a mould
preferably corresponding in shape to the article to be produced it is there subjected
to powerful pressure for the purpose of expelling the water from the material, and
for moulding the mass into the form required.
The fibre, acts as an entangling material for the fine plumbago powder, and acts
also as a filter, retaining the plumbago and preventing it from escaping with the
water through the perforations in the mould.
After the article has been pressed it is removed from the mould and dried in any
suitable manner, and the article is then impregnated or saturated with a semi
drying oil, such as cotton seed oil, and in order to get the best results I heat the
oil to such a temperature that it will impregnate the article.
The mass may be saturated more or less with oil, according to its character and
the use for which it is intended.
I then preferably treat the oiled article in a closed vessel in order to assist in
driving the oil into the interstices of the composition, but this step may be omitted
in some instances.
The article is then thoroughly dried, preferably by artificial means, by being
placed in a suitable retort or oven, and subjected to a sufficient degree of heat to
harden, set and solidify the mass by transforming a portion of the semi-drying oil
into a resinous film throughout the intimate mixture of fibre and plumbago, the
portion of the oil which is not resinified, remaining and serving as a lubricant, in
addition to the plumbago and also rendering the composition more elastic.
The article thus formed is especially adapted for bearings for journal boxes and
other articles subjected to frictional wear, and being solid and dense, makes an
excellent guiding ring for projectiles, as it will be grooved or formed by the
rifling of the gun, but at the same time the ring will withstand any lateral pressure,
and thus the projectile is turned by the rifling through the medium of the ring.

page_text: I have also found that a commutator brush for dynamos or electric motors made
of the composition of matter gives very satisfactory results both as to wear and
electric conductivity and that it also can be used for contact points and arc light
pencils with good results.
In some instances I may dispense with the use of fibre or use a very small
quantity of fibre in proportion to plumbago, the proportion of fibre depending upon
the strain or pressure to which the article is to be subjected.
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 :-
1. A. moulded and hardened composition of matter, consisting essentially of
plumbago and a semi-drying oil, whereby a portion of the oil acts as a binder for
the plumbago, and the balance of the oil acts as a lubricant with the plumbago,
substantially as described.
2. A composition of matter consisting essentially of a mixture of plumbago, fibre
and a semi-drying oil, moulded into the desired form and solidified and hardened by
heat, substantially as set forth.
3. A composition of matter consisting essentially of plumbago and cotton seed oil
solidified and hardened by heat.
4. A composition of matter, consisting of plumbago, finely divided fibre, and
cotton seed oil moulded under pressure into the desired form and solidified and
hardened by heat.
Dated this 9th day of February 1892.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.