IMPROVEMENTS IN CENTRIFUGAL MACHINES
Year: 1875

page_text: LETTERS PATENT to William Shears, of No. 27, Bankside, in the
County of Surrey, for the Invention of " IMPROVEMENTS IN CENTRIFUGAL
MACHINES."
PROVISIONAL SPECIFICATION left by the said William Shears at
the Office of the Commissioners of Patents, with his Petition; on
the 15th June 1875.
I, WILLIAM SHEARS, of No. 27, Bankside, in the County of Surrey,
do hereby declare the nature of the said Invention for
"IMPROVEMENTS
IN CENTRIFUGAL MACHINES," to be as follows:-
1
This Invention has for its object improvements in centrifugal machines.
In constructing centrifugal macbines I fix the basket or drum upon
the upper end of a vertical spindle or axis which passes through the
centre of a hollow or tubular axis; this latter is mounted in suitable:
bearings, and can be rotated by a driving belt passing around a pulley
upon it. On the tubular axis a cone or other suitably shaped surface is

page_text: formed corresponding to a similar surface within the central boss fixed on
the axis of the basket or drum, so that when these surfaces are brought
into contact the basket or drum is driven by the frictional contact
between them.
When it is required to bring the basket or drum to a state of rest the
axis with the basket is raised so that the frictional driving contact is
destroyed, and a disc fixed upon the axis of the basket is brought into
contact with a fixed surface. The friction of these surfaces overcomes
the momentum of the basket, and by this means it is brought to rest.
In some cases I form the frictional driving surface at the upper end
of the hollow axis of a hemispherical shape; I also form a corresponding
cup within the central boss of the basket, and I allow a freedom between
the tubular axis and the spindle within it, so that the basket may be
free to adjust its position during rotation, as is the case in the centrifugal
machine described in the Specification of Britten and Barron's Patent,
No. 118, in the present year.
SPECIFICATION in pursuance of the conditions of the Letters Patent
filed by tho said William Shears in the Great Seal Patent
Office on the 15th December 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
SHEARS, of No. 27, Bankside, in the County of Surrey, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifteenth day of June, in the year of our
Lord One thousand eight hundred and seventy-five, in the thirty-eighth
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said William Shears, Her special license that
I, the said William Shears, my executors, administrators, and
assigns, or such others as I, the said William Shears, my executors,
administrators, and assigns, should at any time agree with, and
no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise,
and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVE-
MENTS IN CENTRIFUGAL MACHINES," upon the condition (amongst others) that

page_text: I, the said William Shears, my executors or administrators, by an
instrument in writing under my, or their, or one of their hands and
seals, should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six
_calendar months next and immediately after the date of the said
Letters Patent.
0
NOW KNOW YE, that I, the said William Shears, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement thereof, that is to say :-
This Invention has for its object improvements in centrifugal machines.
In constructing centrifugal machines I fix the basket or drum upon
the upper end of a vertical spindle or axis which passes through the
centre of a hollow or tubular axis; this latter is mounted in suitable
bearings, and can be rotated by a driving belt passing around a pulley
upon it. On the tubular axis a cone or other suitably shaped surface is
formed corresponding to a similar surface within the central boss, fixed on
the axis of the basket or drum, so that when these surfaces are brought
into contact the basket or drum is driven by the frictional contact
between them.
When it is required to bring the basket or drum to a state of rest the
axis with the basket is raised so that the frictional driving contact is
destroyed, and a disc fixed upon the axis of the basket is brought into
contact with a fixed surface; the friction of these surfaces overcomes the
momentum of the basket, and by this means it is brought to rest..
In some cases, I form the frictional driving surface at the upper end
of the hollow axis of a hemispherical shape, I also form a corresponding
cup within the central boss of the basket, and I allow a freedom between
the tubular axis and the spindle within it, so that the basket may be
free to adjust its position during rotation, as is the case in the centrifugal
machine described in the Specification of Britten and Barron's Patent,
No. 118, in the present year.
In order that my said Invention may be most fully understood and
readily carried into effect, I will proceed to describe the Drawings here-
unto annexed.

page_text: DESCRIPTION OF THE DRAWINGS.
Figure 1 is a vertical section of a centrifugal machine constructed
according to my Invention; a, a is a cast-iron casing forming the frame
of the machine; to it is bolted the piece b, which at its ends holds in
suitable bearings the hollow axis c, which is driven by a belt passing
around the pulley c¹; the axis c terminates at its upper end in a cone c³ ;
d is the basket or drum, and its boss which is hollow has a surface
formed within it to correspond with the cone c³; e is a spindle fixed in
the boss of the basket, it passes down through the hollow axis c, and
beneath its lower end is the lever f.
When the parts are in the position shown by the Drawing, with the
frictional surfaces in contact, the basket is driven with the axis c, but
when the spindle e is lifted by the lever fand its hand scrow the frictional
surfaces are first moved out of contact, and then, if desired, the disc e¹
on the spindle can be brought into contact with the under side of the
lower bearing, and in this way the basket can be brought rapidly to rest.
Figure 2 shows an arrangement similar to that shown by Figure 1,
except that the frictional surfaces are portions of spheres, and freedom
is left between the interior of the axis c and the spindle e, so that the
basket whilst in motion may adjust its position on the axis.
с
What I claim is the construction of centrifugal machines substantially
as described.
In witness whereof, I, the said William Shears, have hereunto
set my hand and scal, this Fourteenth day of December, in
the year of our Lord One thousand eight hundred and seventy-
five.