AN IMPROVED SPRING PISTON RING AND APPLIANCES CONNECTED THEREWITH
Year: 1879

page_text: PROVISIONAL SPECIFICATION left by Robert Henry Ellacott at the Office
of the Commissioners of Patents on the 19th February 1879.
ROBERT HENRY ELLACOTT, of Plymouth, in the County of Devonshire,
Engineer. "AN IMPROVED SPRING PISTON RING AND APPLIANCES CONNECTED
THEREWITH."
My Invention has for its object the application of a cheaper and more efficient
spring ring to pistons of engines, pumps, or any other sliding joints in steam, gas,
water, or other fluids.
I may make my improved rings of cast iron, cast steel, gun metal, or any other
suitable material, and either turned true or cast in a chill, but in all cases my
improvement consists in applying an ordinary spring, spiral, curvilinear, or of any
other suitable form, so as to give elasticity and an outward pressure to the said
rings.
This I effect by casting lugs or projections on the inside of my improved rings,
one on each side of an open joint. These lugs or projections afford suitable bearing
surface to a spring which is pressed in between these two lugs so that its elasticity
presses the lugs, or in other words, the ends of the ring apart. This action has the
effect of pressing the whole body of the ring outwards, causing it to make a secure
steam tight joint on the whole of its outward surface. This spring is manufactured
in any usual manner so as to prevent its elasticity being affected by heat, and may
be of any convenient form, spiral, curvilinear, or as otherwise may be suitable,
When it is not desirable to have projections on the inside of my ring I may simply
place the spring between the split ends of the joint, either leaving the said ends
straight or forming in them a groove or recess to hold the spring in position.
When the spring is in the form of a lyre I may regulate its expansion as the wear
of the ring requires by means of a conical pointed screw tapped through the piston
and acting on the base of the spring, and this screw may be actuated without
withdrawing the piston.
In the case of split piston rings already in use I may adapt my improvement as
described by placing the spring between the split ends, or by attaching in any
convenient manner lugs or projections for the holding of the spring, and these lugs
may be made so that the strain shall come on the ends of the ring, and this I effect
by forming them in such a manner that they cover the exposed split surfaces of the
ring, or I form them in one piece with a tongue closing the opening.

page_text: I should by preference always uso two rings in one groove or joint, arranging
them with their joints or partings in different positions, but preferably at right
angles to one another so as to prevent the steam or other gas or fluid from passing
through the joints or partings.
The joints or partings may be tongued in the usual manner or not, as desired.
I may also arrange my rings three in a single groove or joint, of which the two
outer rings have their openings in different positions. The contre ring I would
make with inclined, coned, or wedged upper surface, with the vertex outwards.
The two outside rings I would make with part inclined under surfaces to fit and
correspond with the outside inclined face of the centre ring. The outward pressure 1
of the centre ring effected by the action of a spring as before described would not
only force the neighbouring rings outwards, but also sidewards, so as to cause the
system of three rings to make an absolutely tight joint both on their outside faces
and also on their edges.
Should wear have taken place it is easy to reset the rings with additional pressure 1
by placing stronger springs into them, as before described, or by packing up
the same springs, and this I may do without withdrawing the rings from the
cylinder.
Some of the many advantages of my improved ring are that it may be adjusted
with the same nicety after continued wear as when new, that its insertion into the 2
cylinder is perfectly easy, that it can be set without any withdrawal of the piston
from the cylinder, and that the adjustment of the spring is so sensitive that the
friction is reduced to a minimum, and the rings are serviceable until completely
worn out.