Year: 1887

page_text: Date of Application, 7th Apr., 1887.
Complete Left, 6th Sept., 1887.
Complete Accepted, 7th Oct., 1887.
I JAMES RIMMER Freedom Street, Walkley, Sheffield, in the County of York,
Engineer do hereby declare the nature of this invention to be as follows.
The object of this invention is to construct a simple and effective arrangement of
piston, in which each piston ring shall be expanded by the action of a separate and
independent spring.
In carrying out my invention, in the construction of a piston for a steam engine for
example, I make two rings divided in the usual way by an oblique cut, and provided
with an internal shoulder or flange to receive the pressure of a spring.
The rings are held upon the piston rod between two plates, one fixed to the rod, and
the other made adjustable, the said plates being less than the internal diameter of the
Engine Cylinder.
The springs are made spiral and conical, the largest coil fits against the shoulder
or flange in the ring as before mentioned, and the smaller end fits round the piston
rod. Between the two springs I place a plate or disc, against which the small ends
of the springs bear this plate does not prevent the rings from coming into contact
with each other on their edges.
9
The springs are made larger in diameter than the inside of the rings, so that they
have to be compressed to be put in their places they are also longer or deeper than
the rings, and have therefore to be compressed before the rings can be brought into
contact.
It will therefore be seen that the springs have two actions, one to expand or
enlarge the diameter of the rings, and the other to force the rings against the end
plates.
FLCL 1
1 1000
ROBT. F. DRURY,
Agent for the Applicant.

page_text: 135
De performed to De particularly described and ascertummed in and by the
following statement :-
The object of this invention is to construct a simple and effective arrangement of
Piston, in which each piston ring shall be expanded by the action of a separate and
independent spring.
And in order that my invention may be clearly understood I annex a sheet of
drawings illustrating same, similar letters of reference indicate similar parts in any
of the figures.
Fig. 1. is an elevation of a piston made according to my invention.
Fig. 2. is a cross section of same.
Fig. 3. is a view of the bottom ring with its spring, removed from the piston.
In carrying out my invention in the construction of a Piston for a Steam Engine
for example, such as shown in Fig. 1. I make two rings A and A', divided in the
usual manner by an oblique cut, and provided with an internal shoulder B, to receive
the pressure of a spring C.
The rings A and A¹, are held upon the piston rod between the two plates D and E,
the one marked D being secured to the rod, which passes through a deep boss forming
part of the plate, the other marked E, being made adjustable; the said two plates are as
usual made of less diameter than the internal diameter of the Cylinder.
The springs C, are made spiral and conical the largest coil when compressed fits
inside the ring and rests against the shoulder B, before mentioned, and the smaller
end fits round the boss portion of the plate D.
Between the two springs I place a thin plate or washer F, against which the small
ends of the springs bear when in position. The plate F may be of the same diameter
as the outer plates D and E, so as to be held between the edges of the rings, or it
may be of smaller diameter so as to allow the edges of the rings to come together.
It will thus be seen that the largest coil of the spring C, will (being compressed)
exert its power to expand the ring, and enlarge its diameter; while the smaller coils
seen in Fig. 3, being also compressed to the position shown in Fig. 2, will exert their
power from the plate F, which is the point of resistance, and force the ring against
the face of the plate E or D, as the case may be.
I prefer to make the plate or washer F, of such smaller diameter, that it will not
be held between the rings but will be free to move upon the long boss of the plate
marked D, in this arrangement if the Springs are of unequal strength, the difference
will be automatically adjusted, and equal pressure put on both rings.

page_text: Having now particularly described and ascertained the nature of my said invention,
and in what manner the same is to be performed, I declare that what I claim is :-
1. In Pistons, the combination of the Springs C, the rings A, A¹ and the plate
or washer F for the purpose specified and substantially as hereinbefore described and
as illustrated.
2. In Pistons, the combination of the coiled springs C, with the rings A, con-
structed substantially as herein before described and shown.
3. A piston, consisting of the rings A and A', the Springs C, washer F, and
plates D & E, constructed and arranged, substantially as herein before described and
illustrated.
ROBT. F. DRURY,
Agent for the Applicant