IMPROVEMENTS IN THE MANUFACTURE OF SPRING RINGS FOR PISTONS AND PUMP BUCKETS
Year: 1877

page_text: LETTERS PATENT to Alexander Oldham, of Dukinfield, in the County of Chester,
for the Invention of "IMPROVEMENTS IN THE MANUFACTURE OF SPRING RINGS
FOR PISTONS AND PUMP BUCKETS."
Sealed the 13th June 1878, and dated the 19th December 1877.
PROVISIONAL SPECIFICATION left by the said Alexander Oldham at the Office
of the Commissioners of Patents on the 19th December 1877.
ALEXANDER OLDHAM, of Dukinfield, in the County of Chester.
"IMPROVEMENTS
IN THE MANUFACTURE OF SPRING RINGS FOR PISTONS AND PUMP BUCKETS."
This Invention relates to the manufacture of coiled steel springs known as
"Mather's piston coils," used in the construction of metallic packing for steam-
engine pistons and pump buckets, upon the principle for which Letters Patent were
granted to William Mather and Colin Mather, dated 28th April 1846, No. 11,183.
The steel is first formed in a flat bar of the required thickness and breadth, and
of a sufficient length to give (when coiled) the diameter required. It is next put
into a furnace until it has attained the requisite heat, and is then passed through
rollers to bend it to the exact circle, and welded together into a hoop. When cold it
is put into a lathe, and bored, turned, and faced, brackets of wrought iron being
put into the inside of the hoop to keep it true whilst the outside is being turned.
It is then "set out" on the outside to the required "pitch" to form the coil and cut
through in a slide lathe by means of a narrow tool about three-sixteenths of an inch
wide. It is then removed from the lathe, and the coils are opened out to the
requisite space to allow of sufficient vertical action, plates being bolted on inside
and outside to keep it in this opened position. It is now put into the furnace, and
brought to the required heat for hardening, which is effected in oil. The plates are
then taken off, and the coil finished in the usual manner, when it will be found to
possess the requisite amount of expansive action both vertically and laterally.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alexander Oldhamn in the Great Seal Patent Office on the 18th June
1878.
ALEXANDER OLDHAM, of Dukinfield, in the County of Chester.
"IMPROVEMENTS
IN THE MANUFACTURE OF SPRING RINGS FOR PISTONS AND PUMP BUCKETS."
"
This Invention relates to the manufacture of coiled steel springs known as
Mather's piston coils," used in the construction of metallic packing for steam-
engine pistons and pump buckets, upon the principle for which Letters Patent
were granted to William Mather and Colin Mather, dated 28th April 1846, No.
11,183.
The steel is first formed in a flat bar of the required thickness and breadth, and
of a sufficient length to give (when coiled) the diameter required. It is next put
into a furnace until it has attained the requisite heat, and is then passed through
rollers to bend it to the exact circle, and welded together into a hoop; or by
preference a hoop or cylinder of the required breadth and diameter is formed from a
solid block in the ordinary manner of making weldless tyres for wheels. When
cold the hoop formed in either of the above-described ways is put into a lathe and
bored, turned, and faced, brackets of wrought iron being put into the inside of the
hoop to keep it true whilst the outside is being turned. It is then "set out" on the
outside to the required "pitch" to form the coil, and cut through in a slide lathe by
means of a narrow tool about three-sixteenths of an inch wide. It is then removed
from the lathe, and the coils are opened out to the requisite space to allow of
sufficient vertical action, plates being bolted on inside and outside to keep it in this
opened position. It is now put into the furnace and brought to the required heat for
hardening, which is effected in oil. The plates are then taken off, and the coil is
finished in the usual manner, when it will be found to possess the requisite amount
of expansive action both vertically and laterally.
It will be evident that my improved method of making these coils a great
economy is effected both in the labor and in the material employed, as under the
old method the hoop was required in the first instance to be at least the width of
the finished coil, or rather wider, and the whole of the metal between the coils had
to be cut away to form the requisite space to give the amount of vertical action
desired. Whereas, according to my Invention, the hoop is made in the first
instance considerably narrower than the finished coil, a single narrow spiral
cut is then made, and the coil is opened out to the required space.
Having now described the nature and object of my said Invention, together with
the manner in which the same is to be or may be performed or carried into practical
effect, I wish it to be understood that I claim as my Invention the manufacture of
coiled steel springs for pistons and pump buckets from a hoop narrower than the
finished coil by making a single narrow spiral cut therein, and then opening out
the coil to the required space to allow of the desired vertical action, and after-
wards tempering the same, substantially as herein-before more particularly
described.
In witness whereof, I, the said Alexander Oldham, have hereunto set my
hand and seal, this Fourteenth day of June, in the year of our Lord
One thousand eight hundred and seventy-eight.