IMPROVEMENTS IN MEANS FOR DIMINISHING FRICTION IN THRUST BEARINGS AND FOOTSTEPS
Year: 1878

page_text: LETTERS PATENT to John Lea and Thomas Lea, Engineers, of Wigan, in the
County of Lancaster, for the Invention of "IMPROVEMENTS IN MEANS FOR
DIMINISHING FRICTION IN THRUST BEARINGS AND FOOTSTEPS."
Sealed the 22nd November 1878, and dated the 30th May 1878,
PROVISIONAL SPECIFICATION left by the said John Lea and Thomas Lea
at the Office of the Commissioners of Patents on the 30th May 1878.
JOHN LEA and THOMAS LEA, Engineers, of Wigan, in the County of Lancaster.
"IMPROVEMENTS IN MEANS FOR DIMINISHING FRICTION IN THRUST BEARINGS AND
FOOTSTEPS."
The application of a mechanical arrangement for reducing the friction of two or
more surfaces working together, which is applicable chiefly to the thrust blocks and
thrust bearings of screw propeller shafts, or can be applied to taking the weight off
the footsteps of heavy upright shafts, and can also be 'applied in a greater or less
degree for a variety of other purposes.
The nature of the said Invention or application consists in this case of being
applied to a screw-propeller shaft, in fixing by key or forging solid to shaft a strong
disc of sufficient diameter, the ends of which disc will be turned half round, i.e.,
hollowed into each end to one-half the diameter of the spherical balls; and into
which half round grooves will be placed as many chilled cast-iron spherical balls,
or steel-hardened balls, or phosphor bronze balls, or other suitable metal; the
number of balls being regulated in proportion to the diameter of the disc and the
nature of their employment.
The pedestals required in connection with the above arrangements will be placed
fore and aft, fitted on a suitable base plate, and made adjustable with bolts, to
take up the wearing of the balls and disc. The ends of the said pedestals having
corresponding half circular grooves to the revolving disc and shaft; the two being
brought together form a race at both sides of disc, in which a cluster of hardened
spherical balls are placed.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Lea and Thomas Leâ in the Great Seal Patent Office on the
30th November 1878.
JOHN LEA and THOMAS LEA, Engineers, of Wigan, in the County of Lancaster.
"IMPROVEMENTS IN MEANS FOR DIMINISHING FRICTION IN THRUST BEARINGS AND
FOOTSTEPS."
The application of a mechanical arrangement for reducing the friction of two or
more surfaces working together, which is applicable chiefly to the thrust blocks and
thrust bearings of screw propeller shafts, or can be applied to reduce the friction of
heavy vertical shafts, and can also be applied in a greater or less degree for a variety
of other purposes, the nature of the said Invention or application.
In the case of being applied to a screw propeller shaft (for instance) a boss is
forged or firmly keyed on to the propeller shaft or other bearings. In the ends of
this boss will be turned half circular grooves.
The pedestals in connection with the above arrangement will be placed fore and
aft, the ends of which will be turned half circular grooves, corresponding with the
grooves in the boss; the ends of the said pedestals and boss coming together and
forming a circular groove, into which will be placed a number of balls; the number
of balls being regulated in proportion to the diameter of the disc or boss and the
nature of their employment.
The said pedestals are to be placed on a suitable base plate, and the pedestals
made adjustable with bolts and keys, to take up the wearing of the balls and the
boss and pedestals.
In witness whereof, I, the said Thomas Lea, have hereunto set my hand
and seal, this Twenty-first day of November, in the year of our Lord One
thousand eight hundred and seventy-eight,
THAMAN TA