A Piston for Engines.
Year: 1894

page_text: Date of Application, 28th June, 1894
Complete Specification Left, 28th Mar., 1895-Accepted, 11th May, 1895
PROVISIONAL SPECIFICATION.
A Piston for Engines.
I, JAMES ALFRED EWINS, of 116 Schofield Street, Nechells, Birmingham, in
the County of Warwickshire, Engineer, do hereby declare the nature of this
invention to be as follows:-
This invention is a piston for gas, oil, or steam engines, or pumps.
The one part of the piston chunk has five, or more, or less chambers, which
I think suitable for the reception of a coil spring, so that when the piston rings are
fitted over the chunk of the piston, in the cylinder, the coil springs expand the
piston rings and keep the cylinder perfectly tight; I likewise claim to make any
other kind of spring, otherwise than coil springs, that I may think suitable for the
work, and of any kind of material otherwise than steel for making the coil, or other
springs, on the top of the springs a radial headed stud is inserted, so as to obtain a
central tension from the coil springs on to the piston rings.
Inside the chunk, piston, or piston back, is a cavity or space between the
chambers, to prevent the heat from interfering with the coil, or other springs.
Dated this 27th day of June 1894.
JAMES ALFRED EWINS.
A Piston for Engines.
I JAMES ALFRED EWINS of 116 Schofield Street Nechells Birmingham in the
County of Warwick 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:-
My invention has for its object a piston for engines and may be applied to either
steam gas or oil engines or pumps and is for the purpose of expanding the piston
rings and thus a perfectly tight fitting piston is obtained so should the rings of the
piston or the inside of the cylinder become worn at all the piston will work quite as
effectively as before.
In order that my invention may be clearly understood I have appended hereunto
a sheet of drawings upon which I have fully illustrated the mode of carrying my
invention into practical effect.
Figure 1 is a broken off sectional view of my piston F.
Figure 2 is an end view of the piston back, or chunk.
Figure 3 is a section through on the line 1-2.
Figure 4 is a view of the piston ring.
Figure 5 is a section of same.
Figure 6 is a view of the spring and stud shewn separately from the cylinder.
My invention consists in forming three, five or more chambers a¹, a², a³, a' and a
in the piston chunk A into each of which I fit a coiled spring B into the top of
these coiled springs I place a stud 62 which has a rounded head 63 over which the
piston ring C is placed.

page_text: It will be seen that the coiled springs B expand the piston ring C and thereby
always retains the ring tightly against the cylinder. The studs 62 are provided
with the round heads 63 and fit into the top of the springs B so that when the piston
ring C is placed around them a central tension is obtained from the springs to the
ring. The ring C being hollowed at c¹ to fit the rounded heads 63 of the stude.
Inside the piston chunk A of the piston F I provide a cavity d for preventing
the heat from damaging the coiled springs B.
I may have any number of these springs B but in all cases an odd number should
be used so that the ring C is expanded by the pressure of two springs on the one
side as against one on the other.
I may also use any kinds of springs other than coiled springs and they may
be made of any suitable kind of material and I may vary the mode of inserting the
springs to suit the various circumstances to be met with.
Having therefore now particularly described and ascertained the nature of my
invention and in what manner the same is to be performed I declare that I
claim is :-
The improvements in pistons for steam gas or oil engines or pumps consisting of
the springs B for expanding the piston rings C substantially as & for the purpose
herein set forth and shewn.