IMPROVEMENTS IN THE CONSTRUCTION OF PISTONS
Year: 1884

page_text: We, ALEXANDER OLDHAM, JAMES OLDHAM, THOMAS OLDHAM, and THOMAS
PERRIN all of Dukinfield in the county of Chester, Engineers do hereby declare
the nature of our invention for IMPROVEMENTS IN THE CONSTRUCTION OF PISTONS
to be as follows:-
"
This invention relates to the construction of pistons specially adapted for Gas
engines, steam winches and locomotive engines, but our improved piston may also
be used for other purposes where a good steam-, water-, or gas-tight piston is:
required with a minimum of friction.
The piston block is made of cast-iron, wrought iron, steel, brass, bronze or
malleable iron, and is turned to the diameter of the interior of the cylinder and
grooved spirally on its edge with any number of grooves to receive a spiral spring:
ring of a corresponding number of coils, the ends of the said ring or coil over-
lapping each other; the exterior of the spring, ring is larger than the internal
diameter of the cylinder and it is compressed or drawn in before introducing it
into the cylinder to give it the required outward action.
The spring ring is made either round, flat, square or of any sectional shape and
of cast iron, steel, brass or bronze.
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page_text: We ALEXANDER OLDHAM JAMES OLDHAM THOMAS OLDHAM and THOMAS PERRIN
all of Dukinfield in the County of Chester Engineers do hereby, declare the nature
of our invention for "IMPROVEMENTS IN THE CONSTRUCTION OF PISTONS" and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
This invention relates to the construction of pistons, specially adapted for gas
engines, steam winches and locomotive engines, but our improved piston may also
be used for steam hammers, pumps, and for, other purposes where a good steam
water or gas tight joint is required with a minimum of friction.
In the annexed drawing Fig. 1 is a face view and Fig. 2. a side view (both being
shown partly in section) of a piston constructed according to our invention.
The piston block a, a is made of cast iron, wrought iron, steel, brass, bronze or
malleable iron, and is turned to the diameter of the cylinder and grooved spirally
upon its edge with any number of grooves b, b to receive a spiral spring ring c, c
having a corresponding number. of coils,, the ends, cx, cx of the ring or coil over-
lapping each other."
The exterior of the spring ring or coil is made larger than the internal
diameter of the cylinder in which it is to work, and it is compressed or drawn in
before introducing it into the said cylinder to give it the required resiliency or
outward action. The spring, ring or coil c c is made either round square 'flat
or of any suitable sectional shape; and of cast iron steel, brass or bronze, the spiral
groove b, b in the piston block a, a being made of a corresponding. form.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is the combination with a spirally grooved piston block of a coiled spring
ring fitting in the said spiral grooves substantially as hereinbefore described and
illustrated by the drawings annexed.