Improvements in or applicable to Metallic Pistons.
Year: 1893

page_text: Date of Application, 28th Jan., 1893
Complete Specification Left, 19th Oct., 1893-Accepted, 25th Nov., 1893
PROVISIONAL SPECIFIOATION.
Improvements in or applicable to Metallic Pistons.
We, CHARLES EDчESTON and ALFRED EDMESTON, of the Firm Archibald
Edmeston and Sons, of Cannon Street Works Salford in the County of Lancaster,
Millwrights and Engineers, do hereby declare the nature of the said invention to be
as follows: ==
The segments or rings are or may be made in the ordinary manner, and our
invention consists in combining therewith a corrugated helical spring in the ring
form the tivo ends of which are connected by a plug or part passing into the two
ends of the helical coil coming together which plug has a collar between its two
ends, or the two ends of the coil to form it into a ring may be united by welding or
brazing or other means but we prefer the said plug with the collar upon it.
The corrugations in the helical coil are upwards and downwards, and the outer
bend of each corrugation rests against the flange on each piston ring, and when these
are pressed together by the junk ring, the corrugations of the circular spring act to
force the piston rings outwards against the sides of the cylinder and the two flanges
of the piston rings against the lower pistou plate and junk ring. The helical rings
according to our invention are made from steel wire or rods coiled into the
helical form in any ordinary manner thus forming a straight helical spring of the
desired length.
Then this straight helical spring is bent into the circular form to fit into a metal
mould of suitable size for the piston, having the desired up and down corrugations
in it and the helical ring is then buttoned or otherwise secured in the said metal
mould, which is then inserted in a furuace or heater, with the helical spring thus
held in it, until it attains the required temperature and is then plunged into the
tempering liquid, and when the helical coil is taken out of the metallic mould when
cold the helical spring will have become of a permanent ring form, having the said
corrugations. By this mode of constructing the coil, it is easily placed in position
between the piston rings, and its action is mado uniform both up and down and
laterally.
Dated the 27th of January 1803.
PETER J. LIVSEY,
A rent
COMPLETE SPECIFICATION.
Improvements in or applicable to Metallic Pistons.
We, CHARLES EDMESTON and ALFRED EDMESTON, of the Firm Archibald
Edmeston and Sous, of Cannon Street Works, Salford, in the County of Lancaster,
Millwrights and Engineers do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement :-
The segments of rings are or may be made in the ordinary manner, and our
invention consists in combining thorewith a corrugated helical spring in the ring
form the two ends of which are connected by a plug or part passing into the two ends
of the helical coil coining together, which plug has a collar between its two ends, or
the two ends of the coil to form it into a ring, may be united by welding or brazing
or other means, but we prefer the said plug with the collar upon it.
The corrugations in the helical coil are upwards and downwards and the outer
bend of each corrugation rests against the flange on each piston ring, and when these
are pressed together by the junk ring, the corrugations of the circular spring act to

page_text: force the piston rings outwards against the sides of the cylinder and the two flanges
of the piston rings against the lower piston plate and junk ring. The helical rings
according to our invention, are made from steel wire or rods coiled into the helical
form in any ordinary manner, thus forming a straight helical spring of the desired
length.
Then this straight helical spring is bent into the circular form to fit into a metal
mould of suitable size for the piston having the desired up and down corrugations
in it, and the helical ring is then buttoned or otherwise secured in the said metal
mould, which is then inserted in a furnace or hoater, with the helical spring thus
held in it, until it attains the required temperature and is then plunged into the
tempering liquid, and when the helical coil is taken out of the metallic mould when
cold, the helical spring will have become of a permanent ring form, having the said
corrugations. By this mode of constructing the coil, it is easily placed in position
between the piston rings, and its action is made uniform both up and down
laterally.
Fig. 1, is a side elevation of one of our improved metallic pistons, one part
showing the metallic pauking rings in section and also part of the corrugated
belical spring when the piston is in its position within the cylinder.
Fig. 2, shows on an enlarged scale an isometrical or perspective view of the two
metallic packing rings some distance apart with the corrugated helical spring in its
position, before the two metallic packing rings are forced into their position as
shown in Fig. 1.
Fig. 3, is an edge elevation, and Fig. 4, a plan view of the block or ring in which
the straight helical spring is placed and held while being heated and tempered, and
formed to the required shape.
In Fig. 1, a, is a part of the piston rod to which one part of the piston or junk
ring a', is secured by a scrow nut a', or by any other convenient arrangement-the
other part of the piston or junk ring a!, is secured by bolts or screws a³, (one of
which is shown in dotted line in Fig. 1,) in an ordinary manner.
The junk rings a¹, and a', may be reversed in their position on the piston rod a,
if desired.
There is a cylindrical part or boss a', on the junk rings that leaves an annular
apace between its periphery, and the metallic packing rings b, for the helical
spring c, which at each up and down bend comes against the flange 6', upon the
metallio rings, first against the flange on the upper, and then against the flange on
the lower metallic packing ring b, the spring c, being also a little larger in circum-
ference before being compressed than it is when in its position shown in Fig. 1.
The screwing of the loose junk ring upon the metallic packing rings so as to
bring them into the position shown in Fig. 1, causes the coils of the spring to be
compressed together and this acts to force the metallic rings b, outwards against
the sides of the cylinder as well as against the junk rings a', and a. The flanges 6',
of the metallic packing rings are alightly bevelled being thickest at their inner
diameter and thinner towards their outer diameter as shown, and as the flanges extend
to more than half the diameter of the helical spring e, it is retained in position.
The flanges & are also sometimes made thinner for pistons of larger diameter.
The metallic packing rings b, are made in an ordinary manner open at one side
with an overlapping tongue piece the opening in one packing ring being placed
reversed to the other when in position in an ordinary manner.
The two ends of the belical spring c, when blocked and tempered to the shape
and size required, are connected or made to come and keep opposite to each other
by a brass or other metal rod e', with a collar c', in its middle (see Fig. 2.).
The ends of this rod c', fit into the interior of the end coils or helices of the
spring which come together, as shown in Fig. 2. The two ends of the helical
spring may be brazed or welded together if desired, but we prefer to use the rod e',
with the collar o', as shown in Fig. 2, which does not interfere with the temper or
elasticity of the spring, and also becauso it is more convenient in many cases to
place the ring in position.

page_text: The mode of constructing the springs which forms one feature of our invention
consists first in making a long straight circular helically coiled spring of the required
diameter of wires or rods of steel of suitable size in an ordinary manner.
Then in making blocking rings to suit the size and diameter of the piston for
which the springs are to be used.
The shaping and tempering block is formed by a ring d, having a groove d', like
a cam groove formed in its outer periphery or oylindrical face, this groove d', is of
a size slightly larger than the diameter of the helical spring to be shaped, and tho
groove is formed with the required to and fro bends as illustrated in Fig. 3.
On the cylindrical periphery of the ring d, at the apex of each bend there is a
turn button d², that can rotate on the shank of a set screw d³, screwed into a holo
in the ring.
One turn button is not shown in Fig. 3, but the hole marked dª, for the set
sorew d is shown.
Another turn button is or may be used to come between two of the other turu
buttons but this turn button is not shown in Figs. 3 and 4.
The end of the helical spring which is to be blocked and tempered, is put into
the groove d', say between two of the turn buttons and is secured therein by the
turn button above referred to but not shown in the figures, then the spring is
bent and forced into the groove until secured by the next button and so on, until it
has passed round the blocking ring, the two ends of the spring coming together
under the same turn button.
When the helical spring is thus secured in the shaping block or ring, the ring or
block in placed in a suitable furnace until heated sufficiently, and then the blooking
ring with the helical spring held in it is immersed in tempering liquid and when
cold, the spring is removed, and being then tempered it will permanently retain the
form given to it when free and at liberty, but as it is elastic and can be compressed
and bent to the required extent when being inserted in the piston it will give
pressure upon the metallic packing rings as hereinbefore explained.
Having now particularly described and ascertained the nature of our said inven-
Lion, and in what manner the same is to be performed, we declare that what
we claim is :-
1. The improved metallic pistons formed by combining a circular coiled helical
spring shaped and tempered as horeinbefore described, with metallic packing rings
of pistons substantially as hereinbefore described and illustrated by the drawings.
2. The construction of cylindrically_coiled helical springs for metallic pistons
shaped and tempered in a circular block or ring, substantially as hereinbefore
described and illustrated by the drawings.
Dated this Seventeenth day of October 1893.
PETER J. LIVSEY,
Agent.