Improvements in Bearings and in Commutator Brushes for Dynamos.
Year: 1892

page_text: COMPLETE SPECIFICATION.
Improvements in Bearings and in Commutator Brushes for
Dynamos.
I, PHILIP HENRY HOLMES of Gardiner in the County of Kennebec, State of
Maine, United States of America, Mechanical Engineer 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 so construct a bearing made of a composition of
lubricating material and fibre that the fibres will be disposed transversely, and the
ends of the fibre will be presented towards the bearing surface.
In the accompanying drawing
Figure 1 is a perspective view of a journal bearing illustrating my invention;
Figure 2 is a sectional view of a journal bearing shewing a shaft mounted
therein;
Figure 3 is a perspective view of a commutator brush made in accordance with
my invention; and
Figure 4 is a view shewing a flat bearing for use as a step, or as a sliding,
bearing.
I will first describe my invention in connection with the manufacture of bearings
in which plumbago and fibre are compressed and bound together.
I mix with finely divided plumbago, the fibre (preferably wood fibre) which is in
a suitable mixing machine intimately mixed with the plumbago and with a liquid
the mixture being then forced into suitable moulds and moulded into the desired form
under great pressure. The moulds are so arranged that the outlets for the liquid
are either at the bearing surface or directly in line with said bearing surface.
In compressing the mixture in the mould, the plunger travels in a direction
parallel with the bearing surface, and consequently the flow of the liquid is transverse,
and the fibres are turned so that they will lie transversely or at right angles to the
bearing surface, or, in other words, so that they will present their ends towards the
bearing surface.
After the mixture has been compressed as described, it is dried and subjected to
treatment with, oil (preferably with a drying oil,) and is then dried or hardened by
heat.
My invention is not limited to the use of a mixture such as that hereinbefore
described but it can be carried out in the manufacture of bearings generally in which
fibre is embodied with a lubricating material, but I have found by experiment that
plumbago is the most available lubricating material, and has the best lubricating
properties.
In Figures 1 and 2, I have shewn an ordinary journal bearing adapted for line
shafting and axle work. In Figure 3, I have shewn a commutator brush or current
collector, which, when made of plumbago and fibre in suitable proportions, is a
good conductor of electricity, the bearing face a in this case being at the end of the
block, while the bearing face a in the form of bearing shewn in Figures 1 and 2, is
at the longitudinal groove or recess.
In Figure 4, I have shewn a flat bearing or step bearing in which the bearing
face a is at the top or bottom.
In the block shewn in Figure 3, the fibres lie parallel with the sides of the block,
whilst in Figure 4, they lie parallel with the ends, and in Figures 1 and 2, the
fibres radiate from the bearing surface.

page_text: 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. For bearings and for commutator brushes for dynamos a composition of
lubricating material and fibres intimately mixed and compressed, the fibres at the
bearing surface being mainly in a direction transverse to the longitudinal line of
the bearing face substantially as hereinbefore described.
2. For bearings and for commutator brushes for dynamos a composition of
plumbago and fibres intimately mixed and compressed, and combined with a binder,
the fibres at the bearing surface lying mainly, in a direction transverse to the
longitudinal line of the bearing face, substantially as hereinbefore described.
3. A bearing made of a composition of plumbago, or other lubricating material,
and fibres intimately mixed and united, the said bearing having a curved bearing
face, the fibres lying mainly in lines radiating from the centre from which the said
curved face is produced, substantially as hereinbefore described.
Dated this 6th day of September 1892.
J. H. JOHNSON & Co.,
Agents.