Improvements in and relating to Piston Packing Rings.
Year: 1888

page_text: Date of Application, 31st Dec., 1888
Complete Specification Left, 25th Sept., 1889-Accepted, 9th Nov., 1889
PROVISIONAL SPECIFICATION.
Improvements in and relating to Piston Packing Rings.
We, WILLIAM THOMSON, of 3 Bruce Street, Hillhead, and JOHN MATTHEW
MACGREGOR of 38 Kirkland Street both in Glasgow, Lanarkshire Engineers do
hereby declare the nature of our Invention to be as follows:-
This Invention has reference to improvements in and relating to metallic spring
packing rings for pistons for engine cylinders and other purposes; and which will
be moro simple in construction, economical, and efficient in action, than the piston
packing rings heretofore in use.
:-
The nature and novelty of our Invention consist all as follows:-
A number of the usual segmental helical springs, of eliptical, flat with round edges,
or other shape, are fitted in sections round the periphery of the piston inside and
between two sets of packing split rings which are bevelled or angled on their inner
surface preferably at angles of thirty-five degrees on the inside towards the centre
joint between the rings or fifty five degrees with the cylinder on which angled
surfaces the cods act to press out the rings as will hereinafter be explained; and
these rings have their outer surfaces resting on sunk flanges on the piston and junk
ring respectively, and which enables the junk ring to be made in the form of a disc
especially for small pistons.
"cod
32
We connect each of the acting spring sections or segments together by a metallic
strip or consisting of a projecting angled central cod part which acts on the
inner surfaces of the rings as before explained, and having stems or pins formed at
each end, which enter and are secured in the ends of the adjacent spring sections or
segments of the spring acting rings so as to form a complete circle of segmental
acting spring rings and cods alternately inserted between the angled surfaces of the
packing rings, when the junk ring is bolted to the piston. The projecting parts of
the "cods" fit into the bevelled rings, and press them by the elasticity or tension
of the springs against the inside 'surface of the cylinder in which the piston works
and a thoroughly fluid tight working packing is thus obtained. The split working
packing rings would be fitted with the usual joint tongues on their outer faces at
their cut spring joint, so as to make them fluid tight, in the same manner as other
spring packing rings are.
For enlarging or tightening up these new segmental acting spring rings when
required, this is effected by inserting a longer spring ring between any one of the
cods, or by inserting a washer of any desired thickness on the stems of the cods
which enter the springs between the cods and the ends of the springs.
Datad the 20th December 1888
W. R. M. THOMSON & Co.,
Agents.
COMPLETE SPECIFICATION.
Improvements in and relating to Piston Packing Rings.
We, WILLIAM TномSON, of 3 Bruce Street, Hillhead, and JOHN MATTHEW
MACGREGOR, of 38 Kirkland Street, both in Glasgow, Lanarkshire, Engineers, do
hereby declare the nature of our invention, and in what manner the same is to be
performed to be particularly described and ascertained in and by the following
statement in writing, reference being had to the accompanying Sheet of Drawings,
and to the letters and figures marked thereon, that is to say :—
This Invention has reference to improvements in and relating to metallic spring
packing rings and their fittings for pistons for engine cylinders and other purposes;

page_text: and which will be more simple in construction, economical, and efficient in action
than these have been as heretofore in use.
And in order that our said Invention, and the manner of performing or carrying
the same into effect or practice may be properly understood, we have hereunto appended
an explanatory Sheet of Drawings, in which the same reference letters are used to
indicate corresponding parts in all the figures where shown. Figure 1 is a side
elevation, half in section, of a piston P, Pi, as fitted with our improvements relating
to the spring packing rings A, A. Figure 2 is a frout elevation of same with the
junk ring P and upper ring A of the piston removed, to show the segmental
springs and our improved fittings. Figure 3 is an elevation of the piston P corre-
sponding to Figures 1 and 2, showing the cut spring joint part A" of the packing
rings A, A. Figure 4 is a view of a piston corresponding to Figure 1, showing our
improvements as applied to a modified form or section of the inner piston ring A, A¹,
having its working face A' formed at an angle of 45° to the vertical and with the
apexes of the cod parts cnt away. Figures 5 and 6 show end and plan views of our
new or improved cods and stems a, a, as fitted to the springs S in Figures 1 and 4
respectively while Figure 7 shows sido and end views of one of the segmental helical
springs S detached in which the ends a¹ of the new cod pieces a, a, are fitted.
Referring to these Drawings:-A number of the usual segmental helical springs S,
of eliptical flat section with round edges as shown particularly in Figures 2 and 7 or
it might be of other shape, are fitted as shown in Figure 2 in sections round the
periphery of the piston P within and between two sets of packing split rings A, A,
which are bevelled or angled on their inner surfaces A', at angles of about thirty-five
degrees on the inside towards the centre joint between the rings A, as shown in
Figure 1, or preferably for thin rings and cods at angles of 45° to the vertical as
shown in Figure 4, or other equivalent suitable angles. On these angled surfaces A¹
the cods a a act to press out the rings A circumferentially and laterally against the
inner turned flange P, and junk ring P₁ as will hereinafter be explained; and these
rings A have their flat surfaces resting and working on the inner turned surface of
the sunk flange of the piston P and junk ring P respectively, and which enables the
junk ring P¹ to be mado in the form of a ring disc.
By our improvements we connect each of the acting spring sections or segments S
together by a metallic strip or cod consisting of a projecting double angled central
cod or wedge part a made to fit and act on the inner angled surfaces A, A', of the
rings A, A, as before explained, and have stems or pins a formed at each end, which
enter and are secured in the ends of the adjacent spring sections or segments
of the
spring acting rings so as to form a complete circle of segmental acting spring rings S
and cods a a alternately inserted between the cod parts and angled surfaces A' of the
packing rings A, when the junk ring P¹ is screwed to the piston P. The projecting
parts a of the cods a, a', fit into the bevelled parts A' of the rings A and press them
by the elasticity or tension of the springs S against the inside working surface of the
cylinder in which the piston P works, and against the inner surfaces of the rim P and
junk ring P, and a thoroughly fluid tight working packing is thus obtained. The split
working packing rings A, A', are fitted with the usual joint tongues b in recesses in
their outer faces at their cut spring joint parts A" shown in Figure 3, so as to make
them fluid tight at this part, in the same manner as other spring packing rings are.
For enlarging or tightening up these now segmental acting spring rings when
required, this is effected by inserting a longer spring ring S between any two of the
cods a, a¹; or as seen in Figure 5, this can be attained by inserting a washer a of
any desired thickness on the stems a' of the cods a, between the cods a and the ends
of the springs S.
Referring to Figures 4 and 6, this shows an arrangement in which the rings A are
made thinner, that is parallelly recessed for some distance in at b¹ and the angle made
preferably more obtuse as about 45 degrees, and have a flat part in the bottom of
the recess at 61, cutting away also the apex end part of the cod at all to give freedom
of action for the cod a, and as seen more particularly in the detached views Figure 6.
In both cases the ends of the springs S bear up against the ends a¹ of the cods a

page_text: and are clear of the beveled surfaces A¹ of the rings A and of the inner body of
the piston P.
=
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 :-
First. The construction or arrangement and combination of the parts, of piston
packing rings, and their fittings, in which the pressure of segmental coiled springs
are transmitted by means of double angled cods or wedge pieces to act on the corre-
sponding angled turned inner surfaces of the spring packing, rings, substantially as
herein described, in reference to and shown in the accompanying Drawings.
Second. In piston packing rings, the fitting and use of double angled cods or
wedge pieces acting on the angled surfaces of the rings and having their stems
inserted in the ends of segmental springs to transmit the pressure of these springs
to the inner angled surfaces of the packing rings, substantially as and in the
manner herein described in roference to and shown in the accompanying
Drawings.
لنت
لسيد
2
L
1000
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.