THE ADMISSION OF STEAMINTO THE CYLINDERS OF STEAM ENGINES BY AN EQUILIBRIUM VALVE
Year: 1856

page_text: LETTERS PATENT to Peter Gaskell, of the Parish of Sculcoates, in the
Town of Kingston-upon-Hull, and County of the same Town, Steam
Engine Maker, for the Invention of "THE ADMISSION OF STEAM INTO THE
Sealed the 5th May 1857, and dated the 10th November 1856.
PROVISIONAL SPECIFICATION left by the said Peter Gaskell at the.
Office of the Commissioners of Patents, with his Petition, on the 10th
November 1856.
I, PETER GASKELL, of the Parish of Sculcoates, in the Town of Kingston-
upon-Hull, and County of the same Town, Steam Engine Maker, do hereby
declare the nature of the said Invention for "THE ADMISSION OF STEAM
INTO THE CYLINDERS OF STEAM ENGINES BY AN EQUILIBRIUM VALVE," to be as
follows:-
The equilibrium valve is composed of two plates of bell metal or other
suitable metal, made either to revolve on a metal shaft in the case of a rotary
valve, or to slide in the case of a sliding valve (as may be required), at a
distance of about two or three inches apart from each other, within a metal
valve box of a circular or square form, as may be required, the valve plates
and box being all ground smooth, and fitted so as to be perfectly steam-tight
except at the apertures in the lower plate, herein-after mentioned. The steam
intended to pass into the cylinder is first admitted into the valve box in the
intermediate space between such two plates. The pressure of the steam in
the valve box on the upper or outer plate thus counterbalances (or nearly so)
its pressure in a contrary direction on the lower or inner plate, and produces
an equilibrium, thereby obviating in a great degree the friction of the valve

page_text: as it revolves or slides (as the case may be). The upper or outer of such two
plates is without any hole or aperture for the passage of steam. The lower or
inner of the two plates is perforated with holes or apertures proper for the
passage of the steam from the valve box into the cylinders as the valve
revolves or slides.
The diameter or the area of the surface of the upper or outer plate is
somewhat less than that of the lower or inner plate; and thus the pressure
of the steam, though very nearly at an equilibrium, is somewhat greater on
the latter plate on account of its greater surface than on the other, and by
this means the moving part of the valve is maintained in its proper placo
with sufficient tightness to secure its efficient working, but nevertheless
without any such pressure on its seat as to cause disadvantageous friction.
It will be obvious that the relieving (by the simple means above described)
of the moving part of the valve from nearly the whole of the pressure of the
steam upon it must. lessen the friction in a most considerablo degree, and
thereby effect (as my equilibrium valve is proved to do) a correspondingly
great saving in the consumption of fuel required for working the engine as
compared with the quantity consumed in working engines constructed with
any of the valves at present in use, and also an equal saving of tallow or
grease.
My equilibrium valve will also be less liable to derangement or accident,
whether in steam vessels, locomotives, or any other kind of engines, than any
of the valves now in use.
The improvement effected by my Invention has the further advantage of
being applicable to all kinds of steam engines, whether constructed with
"slide valves, or "rotary," or "male and female," or any other description of
valve for admitting steam into the cylinders, and is equally advantageous when
applied to locomotive, or marine, or stationary steam engines of whatsoever
kind.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed S
by the said Peter Gaskell in the Great Seal Patent Office on the
9th May 1857.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, PETER
GASKELL of the Parish of Sculcoates, in the Town or Borough of Kingston-
upon-Hull, and County of the same Town, Steam Engine Maker, send 3
greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by. Her Letters
Patent, bearing date the Tenth day of November, in the year of our Lord.
One thousand eight hundred and fifty-six, in the twentieth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the
said Peter Gaskell, Her special licence that I, the said .Peter Gaskell, my
executors, administrators, and assigns, or such others as I, the said Peter
Gaskell, my 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 "THE ADMISSION OF STEAM INTO
THE CYLINDERS OF STEAM ENGINES BY AN EQUILIBRIUM VALVE,"
upon the condition
(amongst others) that I, the said Peter Gaskell, my executors or admini-
strators, by an instrument in writing under my, or their, or one of their hands.
and seals, 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 I, the said Peter Gaskell, do hereby declaro the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:-
The equilibrium valve is composed of two plates of bell metal.or other
suitable metal, made either to revolve on a metal shaft in the case of a rotary
valve, or to slide in the case of a sliding valve (as may be required), at a
distance of about two or three inches apart from each other, within a metal
valve box of a circular or square form, as may be required, the valve.plates
and box being all ground smooth and fitted so as to be perfectly steam-tight,
except at the apertures in the lower plate, herein-after mentioned. The steam
intended to pass into the cylinder is first admitted into the valve box in the
intermediate space between such two plates. The pressure of the steam in
the valve box on the upper or outer plate thus counterbalances (or nearly so)
its pressure in a contrary direction on the lower or inner plate and produces an
equilibrium, thereby obviating in a great degree the friction of the valve as
it revolves or slides (as the case may be). The upper or outer of such two
plates is without any hole or aperture. for the passage of steam. The lower or
inner of the two plates is perforated with holes or apertures proper for the
passage of the steam from the valve box into the cylinders as the valve
revolves or slides.

page_text: The diameter or the area of the surface of the upper or outer plate is some-
what less than that of the lower or inner plate, and thus the pressure of the
steam, though very nearly at an equilibrium, is somewhat greater on the latter
plate on account of its greater surface than the other, and by this means the
moving part of the valve is maintained in its proper place with sufficient
tightness to secure its efficient working, but nevertheless without any such
pressure on its seat as to cause disadvantageous friction.
It will bo obvious that the relieving (by the simple means above described)
of the moving part of the valve from nearly the whole of the pressure of the
steam upon it must lessen the friction in a most considerablo degree, and
thereby effect (as my equilibrium valve is proved to do) a correspondingly
great saving in the consumption of fuel required for working the engine as
compared with the quantity consumed in working engines constructed with
any of the valves at present in use, and also an equal saving of tallow
or grease.
My equilibrium valves will also be less liablo to derangement or accident,
whether in steam vessels, locomotives, or any other kind of engines, than any
of the valves now in use.
The improvement effected by my Invention has the further advantage of
being applicable to all kinds of steam engines, whether constructed with "slide
valves," "rotary," or "male and female," or any other description of valvo for
admitting steam into the cylinders, and is equally advantageous when applied
to locomotive, or marino, or stationary steam engines of whatsoever kind.
The above particulars, as explained more fully by the Drawings accom-
panying and annexed to this Specification, describe and ascertain the nature of
the said Invention, and the manner in which the same is to be performed;
but I would have it understood that I do not confine myself to the precise
form or dimensions of the valve above described, or as shewn in the accom-
panying Drawings, as these may be varied according to circumstances or the
fancy of the engineer.
In witness whereof, I, tho said Peter Gaskell, have hereunto set my
hand and seal, the Eighth day of May, One thousand eight hundred
and fifty-seven.
PETER GASKELL. (L.B.)