IMPROVEMENTS IN PISTONS FOR STEAM ENGINE AND OTHER CYLINDERS." IN PISTONS FOR STEAM ENGINE AND OTHER CYLINDERS
Year: 1857

page_text: LETTERS PATENT to John Atherton Molineaux and Joseph Nichols, of
Brighton, in the County of Sussex, for the Invention of "IMPROVEMENTS
IN PISTONS FOR STEAM ENGINE AND OTHER CYLINDERS."
IN PISTONS FOR STEAM ENGINE AND OTHER CYLINDERS."
Sealed the 30th March 1858, and dated the 3rd October 1857.
PROVISIONAL SPECIFICATION left by the said John Atherton Molineaux
and Joseph Nichols at the Office of the Commissioners of Patents, with
their Petition, on the 3rd October 1857.
We, JOHN ATHERTON MOLINEAUX and JOSEPH NICHOLS, of Brighton, in the
County of Sussex, do hereby declare the nature of the said Invention for
IMPROVEMENTS IN PISTONS FOR STEAM ENGINE AND OTHER CYLINDERS," to be
as follows:-
This Invention relates to the introduction of holes or passages having
separate or connected valves fitting therein or thereover, by which the pressure
acting upon the face of the piston is permitted to enter into the annular or
other chamber or space formed by the piston and its cover plate, and behind
the packing rings or other packing or means employed for compensating for
the wear and the inequalities of the surface against which it acts, whether in
pistons fitted with one or more metal packing rings, and however they may be
constructed, or where such piston or buckets for pumps are caused to work
by the expansion of any elastic material, accurately filling the diameter of
the barrel or cylinder in which it works. For the pistons of locomotive

page_text: engines, where the steam alternately acts in rapid succession upon the opposite
faces of the piston, this Invention is applied in the following manner:-
The piston and its cover plate have one or more holes bored through them,
each of which would give a clear passage way through from one side of the
piston to the other, but for the introduction of a suitable valve to each
opening, fitted within and opening inward; thus, on one of these valves
being subject to the pressure of the steam, which, gaining access to the
interior of the piston, closes the valve covering.or openings on the opposite
side of the piston to that upon which the pressure is for the moment acting,
and thus permits of the steam exerting its pressure within the chamber
behind the metallic ring or rings or other packing, and so keeps the said
packing in close contact with the cylinder. The piston having reached the
end of the stroke, and the equilibrium of the internal pressure being disturbed
as by the steam being admitted on the opposite side of the piston, each valve
is immediately acted upon and closes the opening or passage on the opposite
side of the piston, when the steam enters the chamber or space within the
piston as before. For this form of piston, however, we prefer instead of using
single or separate valves to close the opposite holes, to employ a winged
spindle valve, the wings working in the holes bored in the piston and cover
plate, and permitting the admission of steam between them, which wings also
act as guides for the backward and forward action of the valve within the
piston. Such winged spindle may have two buttons cast thereupon at a
suitable distance apart or by a suitable enlargement of the diameter of the
centre part or portion of such spindle, the ends of which are turned and faced,
and made to fit accurately the internal surface of the piston, and cover the
holes which have been bored truly through; the piston and cover are faced
on the inside to form a seating for the valve and ensure its being steam-tight.
The extent of motion or travel which the double-faced valve has within the
thickness of the piston can be regulated by the proportion which the length
of the valve or the distance between its two faces bears to the distance
internally between the piston and its cover plate.
For the pistons of other kinds of engines, and for the buckets and pistons
of pumps, we apply the arrangement of double or unconnected valves before-
described on the double-faced winged spindle valve acted upon and closed
alternately by the working pressure, and by means of which valves such
working pressure (whether steam, air, gas, water, or other fluid or liquid)
is employed or permitted to act upon the packing of such piston or bucket, or
their mechanical equivalent as a substitute for metallic or other springs.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Atherton Molineaux and Joseph Nichols in the Great
Seal Patent Office on the 1st April 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JOHN
ATHERTON MOLINEAUX and JOSEPH NICHOLS, of Brighton, in the County of
Sussex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Third day of October, in the year of our Lord One
thousand eight hundred and fifty-seven, in the
year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto us, the said
John Atherton Molineaux and Joseph Nichols, Her special licence that we,
the said John Atherton Molineaux and Joseph Nichols,
executors, admini-
strators, and assigns, or such others as we, the said John Atherton Molineaux
and Joseph Nichols, executors, administrators, and assigns, should at any
time agree with, and no others, from time to time, and at all times thereafter,
during the term therein expressed, should and lawfully might make, use,
exercise, and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
PISTONS FOR STEAM ENGINE AND OTHER CYLINDERS," upon the condition (amongst
others) that we, the said John Atherton Molineaux and Joseph Nichols, by
an instrument in writing under our, or their, or one of their hand and seal,
should particularly describe and ascertain the nature of the said Invention,"
and in what manner the same was to be performed, and cause the same to
be filed in the Great Seal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.
NOW KNOW YE, that we, the said John Atherton Molineaux and Joseph
Nichols, do hereby declare the nature of our said Invention, and in what
manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement and accompanying Drawing:-
This Invention relates to the introduction of holes or passages, having
separate or connected valves fitting therein or thereover, by which the
pressure acting upon the face of the piston is permitted to enter into the
annular or other chamber or space, formed by the piston and its cover plate,:
and behind the packing rings or other packing or means employed for
compensating for the wear and the inequalities of the surface against which
it acts, whether in pistons fitted with one or more metal packing rings, and
however they may be constructed; or where such pistons or buckets for pumps

page_text: are caused to work by the expansion of any elastic material, accurately filling
the diameter of the barrel or cylinder in which it works. For the pistons of
locomotive engines where the steam alternately acts in rapid succession upon
the opposite faces of the piston, this Invention is applied in the following
manner:―
The piston and its cover plate have one or more holes bored through them,
each of which would give a clear passage way through from one side of the
piston to the other but for the introduction of a suitable valve to each
opening, fitted within and opening inward, thus on one of these valves being
subjected to the pressure of the steam, which gaining access to the interior of
the piston, closes the valve covering the opening or openings on the opposite
side of the piston to that upon which the pressure is for the moment acting,
and thus permits of the steam exerting its pressure within the chamber
behind the metallic ring or rings, or other packing, and so keeps the said
packing in close contact with the cylinder; the piston having reached the
end of the stroke and the equilibrium of the internal pressure being dis-
turbed, as by the steam being admitted on the opposite side of the piston,
each valve on that face of the piston is immediately acted upon, and closes
the opening or passage on the opposite side of the piston, when the steam
enters the chamber or space within the piston as before. For this kind of
piston, however, we prefer instead of using two single flap or other [separate
valves for closing the opposite holes, to employ double-winged spindle valves
of the form shewn in the accompanying Drawing, Fig. 1, the wings working
in the holes bored in the piston and cover plate, and permitting the admission
of steam between them, whilst these wings also act as guides for the back-
ward and forward action of the valves within the piston; such winged spindle
valves are formed with two collars or suitable enlargement behind each
winged portion, so that one side of each acts as the valve face for the interior
or seat of the opening. These collars are turned and faced, and the wings
are turned so as accurately to fit the hole in which it works, whilst the collars
or enlargements being truly faced fit accurately against the internal surface of
the piston, and cover moreover the holes which have been bored truly through;
the piston and cover are faced on the inside to form seatings for their valves,
and insure their being steam-tight. The extent of motion or travel which the
double-faced valve has within the thickness of the piston can be regulated by:
the proportion which the length of the valve on the distance between its two
faces bears to the distance internally between the piston and its cover plate.
Instead of constructing the double-winged valves in one piece as just

page_text: described, we also make the two winged collar valves separate, the inner end
of one valve having a triangular or other stud projecting from its face, whilst
the other has a circular recess or hole of suitable depth bored therein to
receive the stud of the opposite valve. Into this recess or circular hole we
place a spiral spring, against which the end of the stud comes in contact, and
which spring resists in any suitable degree the entrance of the said stud
beyond an extent sufficient for its giving a bearing to the stud or spindle, but
upon the pressure of steam acting against the face of the valve, the spring
will yield and permit of the two valves coming closer together, back to back,
and thus permit of a passage way for the steam on one side of the piston,
whilst the valve on the opposite side prevents its escape; a stronger or weaker
spring may be substituted according to the pressure of steam at which the
engine is worked.
For the pistons of other kinds of engines, and for the buckets and pistons
of pumps, we apply the arrangement of double or unconnected valves before,
described, or the double-faced winged spindle valves, acted upon and closed
alternately by the working pressure, and by means of which valves such
working pressure (whether steam, air, gas, water, or other fluid or liquid,)
is employed or permitted to act upon the packing of such piston or bucket
or their mechanical equivalents as a substitute for metallic or other springs
for keeping the packing extended whilst the piston or bucket is at work.
By the employment of these valves and the working pressure within the
cylinders of locomotive engines for maintaining the packing expanded whilst
the piston is at work, enables a locomotive engine to descend an incline or
otherwise when the steam is shut off without continuing the wearing action of
the piston packing within the cylinder, as is at present the case with pistons
having their rings extended by means of metallic springs, and at the same
time reduces the strain upon the wear and tear of other parts of the
engine.
:
We prefer to employ one metallic packing ring instead of several, and we
cover the joint of such metallic packing ring by means of a curved plate, as
shewn in the accompanying Drawing, and where the wear and tear of the
metallic packing ring is great and the difficulty of access to the piston packing
ring for adjustment is considerable, we prefer to employ such an arrangement
as shewn in Fig. 6, by which a block piece having two serrated extremities
which take into similar serrations formed at or near each end of the split
metallic packing ring; thus as the ring wears, it passes over another tooth
at each end, and there is retained until the ring is further worn, when the
ring again expands and is retained in its position by the block piece.

page_text: Instead of employing the ordinary circular hoop or elliptic band spring for
expanding the packing rings of pistons, by which a constant pressure is
maintained within the piston, we sometimes apply in conjunction with the
valves constructed according to our Invention, an expanding wedge piece with
a small pressure spring behind to keep it in its place, as shewn in Fig. 7,
and a modification of its arrangement shewn in Fig. 6 is represented in
Fig. 8, the spiral spring in the latter case being only employed to keep the
serrated joint plate in its. place, and as before stated not for the purpose of
expanding the metalic packing ring, this being effected by the pressure of the
steam.
We would here remark that the entire contents of the piston chamber is
not changed at each stroke, whereby that quantity of steam would become
wasted, for whilst the contents remain the same or nearly so, the position or
direction of the pressure is alone changed with the change in the direction of
the motion of the piston.
In the accompanying Drawing, Fig. 1 is a longitudinal section of the double
wing spindle valve for pistons as herein-before described, this double valve
being cast or formed in one piece with two winged terminations and two
collars. Fig. 2 is a view of one of the winged ends of the valve; a is the
body of the valve; b, b, the two collars forming the valve faces; c, c, the two
winged ends of the valve, each end having three wings. The length of this
valve between the two faces b, b, should be as much less than the width or
distance between the inner faces of the piston and cover as will enable or
admit of a sufficient passage way for the steam to enter or communicate the
external pressure to the interior thereof; this valve opens and closes the
opposite openings or valve, and acts in the piston alternately by the change in
the direction of the external pressure and without a spring. Fig. 3 is an
external elevation of a piston valve, which instead of being cast or formed
in one piece, as in Figs. 1 and 2, is constructed in two parts; these are
extended, and the two valve faces when there is no external pressure are
kept against, and keep closed, their respective openings or passages into the
piston by means of a spring. In this Figure, the spindles are formed with
longitudinal corrugations or grooves, forming seven wings instead of three, as
in Figs. 1 and 2; the bearing surface of the ends is thereby more equally
distributed, although any other number of wings and grooves or passages
may be substituted; in this valve a spiral spring is enclosed in a socket or
chamber, into which also a winged projecting stud end d of the opposite part
of the valve works, and acts as a guide for the play of the valve when at
work. Fig. 4 is an end view of Fig. 3. In Fig. 5, a vertical section exhibits

page_text: the arrangement of the parts, a, a, being the two parts of the body of the
valve; the two valve faces b, b, expanded by the spiral spring f, contained
within the socket e, which socket also receives the smaller winged stud d of
one part of the valve; c, c, being the winged spindles or guide studs which
work in the holes, opening, or passages, through the piston plate and cover;
by this arrangement the valve faces are kept better in their places, and the
shocks which would be produced when employing the valves Figs. 1 and 2 in
very quick working pistons is avoided. Fig. 6 is a plan of a piston with the
cover plate removed, being fitted with two valves, according to this Invention;
it is also shewn as fitted with an arrangement herein-before described for
compensating for the wear of the packing ring, which last-mentioned arrange-
ment, however, if used, may be varied. Fig. 7 is another plan view of a
piston, the cover plate being removed. In this piston is fitted two valves,
according to our Invention, each valve having three wings, as in Figs. 1
and 2. A wedge piece, having a spiral spring at the back thereof, is shewn
as employed for compensating for the wear of the metal packing ring. Fig. 8
is another plan view of a piston, the cover plate being removed; this piston
is fitted with two valves, according to our Invention, each valve being shewn
with four wings; a ratchet faced extending piece for compensating for the
wear of the packing, being a modification of the arrangement shewn in Fig. 6..
Fig. 9. is a longitudinal section of part of an horizontal cylinder, exhibiting:
a like section of the piston, which is shewn as fitted with two valves,
according to our Invention, and similar to those shewn at Figs. 3, 4, & 5,
but having only four wings to the spindle ends; Fig. 10 being a view of
the piston of Fig. 9, with the cover plate removed. In Figs. 9 & 10 we
have shewn the ordinary arrangement which we employ, the metalic packing
ring being fitted with a thin back cover plate to "break the joint" or keep it
steam-tight.
In the several Figures in the accompanying Drawing we have shewn
pistons of a similar character, being such as are employed for locomotive
engines; but valves constructed according to our Invention may be applied
to other forms of pistons for working with steam, air, gas, water, or other
fluid or liquid, and moreover we have only shewn two of the forms of valves
constructed according to our Invention, by which the external pressure may
be admitted into the interior of steam or other piston or pump buckets, for the
purpose of keeping the packing thereof close against the face of the cylinder
or barrel, although we in certain cases employ two flap valves connected
together and so arranged as to close and open alternately the opening or

page_text: passage on each side of the piston. This arrangement may be substituted in
some cases for the valves shewn at Figs. 1, 3, & 5.
Having now described our Invention, we wish it to be understood that we
are aware that the pressure of steam, and other fluid, and gaseous, or other
elastic bodies. contained within cylinders, barrels, and chambers, has heretofore
been employed, and also various methods of employing the said pressure for. the
purpose of acting in manner described have been tried, but what we claim as.
our Invention is,―
First, the construction of pistons with holes or passages, as described,
having separate or connected valves fitting therein or thereover, by which the
pressure acting upon the face of the piston is admitted into the interior of
the piston and permitted to act behind or upon the back of the elastic
packing, first from one side or face of such piston, and then from the other,.
and by which means such packing is caused to expand and fit the cylinder
or barrel within which it works, as herein described.
Secondly, the several forms or arrangements of valves herein described and
illustrated, when either or any of such double valves are applied to pistons or
buckets, for the purpose herein described, by which the external pressure is
caused to act alternately from and through openings or passages made on
each side of such piston or bucket, and also whether such valves are employed
alone or in conjunction with extending pieces acted upon or retained in their
places by springs.
In witness whereof, I, the said John Atherton Molineaux, on behalf of
myself and Joseph Nichols, have hereunto set my hand and seal, this
First day of April, in the year of our Lord One thousand eight
hundred and fifty-eight.
Witness,
GEORGE CHURCHILL,
18, Salisbury Street, Strand.
J. A. MOLINEAUX. (L.S.)