Improvements in Metallic Packings for Cylinder Pistons and Valve Pistons.
Year: 1894

page_text: Date of Application, 7th Dec., 1894
Complete Specification Left, 31st Aug., 1895-Accepted, 5th Oct., 1895
PROVISIONAL SPECIFICATION.
Improvements in Metallic Packings for Cylinder Pistons and
Valve Pistons.
I, GEORGE WHARTON SUTHERLAND, of Encliffe, Stranraer, in the County
of Wigton, North Britain, Engineer, do hereby declare the nature of this invention
to be as follows, that is to say :-
My said invention has for its object to improve the construction and arrange-
ment of parts of metallic packings of pistons used in cylinders or as valves.
In carrying out my invention I employ a single expansible ring which is,
preferably, pressed outwards by a series of equally distributed helical springs
disposed radially. The expansible ring is fitted accurately between the flange on
the piston body and a narrow uncut ring fitted to the junk ring. Helical or other
suitable springs are applied between the junk ring and the narrow uncut ring in a
manner to keep the outer part of the latter in close contact with the edge of the
expansible ring. The narrow uncut ring prevents steam from getting behind the
expansible ring, and it also prevents any play or movement of that ring between
the junk ring and body flange. If preferred the narrow uncut ring may be fitted
to the body flange instead of the junk ring.
The radial springs which press out the expansible ring are by preference held
between small blocks shaped or adjusted to limit the extent to which the expansible
ring can move inwards. Or the radial springs may be combined with holders or
screws screwed into the piston body so as to be adjustable more or less outwards
and at the same time limit the inward movement of the expansible ring.
Dated this Sixth day of December 1894.
EDMUND HUNT,
Applicant's Agent.
Improvements in Metallic Packings for Cylinder Pistons and
Valve Pistons.
I, GEORGE WHARTON SUTHERLAND, of Eucliffe, Stranraer, in the County
of Wigton, North Britain, Engineer, do hereby declare the nature of this invention
and in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement, that is to say :-
My said invention has for its object to improve the construction and arrange-
ment of parts of metallic packings of pistons used in cylinders or as valves.
In carrying out my invention I employ a single expansible ring which is,
preferably, pressed outwards by a series of equally distributed helical springs
disposed radially. The expansible ring is fitted accurately between the flange on
the piston body and an uncut ring fitted to the juuk ring. Helical or other
suitable springs are applied between the junk ring and the uncut ring in a manner
to keep the outer part of the latter in close contact with the expansible ring. The
uncut ring prevents steam from getting behind the expansible ring, and it also
D

page_text: prevents any play or movement of that ring between the junk ring and body
flange. If preferred the uncut ring may be fitted to the body flange instead of
the junk ring.
And in order that my said invention and the manner of performing the same
may be properly understood I hereunto append a sheet of explanatory drawings,
to be hereinafter referred to, and showing by way of example, parts of a cylinder
piston, as made with my improved metallic packings.
Figure, 1, of the drawings is a radial section of a piston, and
Figure, 2, is a plan with the part of the junk ring removed.
Figure, 3, is a radial section at a different part, and
Figure, 4, is a plan with the parts of the junk ring and uncut ring removed.
In these drawings the same reference letters are used to mark the same or like
parts wherever they are repeated.
I employ a single expansible ring, A, which is cut as usual and fitted with a
tongue and is pressed outwards preferably by a series of equally distributed helical
springs, B, disposed radially. The expansible ring, A, is fitted accurately between
the flange, C, on the piston body, D, and an uncut ring, E, fitted to the junk
ring, G, and shaped with a narrow outer edge, H. Helical springs, J, placed in
recesses in the uncut ring, E, are applied between the junk ring, G, and the uncut
ring in a manner to keep the outer part of it in close contact with the edge of the
expansible ring, A. The uncut ring, E, prevents steam from getting behind the
expansible ring, A, and it also prevents any play or movement of that ring between
the junk ring, G, and body flange, C. If preferred the uncut ring, E, may be fitted
to the body flange, C, instead of the junk ring, G.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
The improved metallic packing for cylinder pistons and valve pistons, com-
prising in combination a single expansible cut ring pressed outwards by springs,
and an uncut ring fitted between the expansible ring and the junk ring or body
flange and pressed towards the expansible ring by springs substantially as herein-
before described.
Dated th Th
J
Ammunt 1005
EDMUNT HUNT,
Applicant's Agent.