CERTAIN IMPROVEMENTS IN STEAM ENGINES
Year: 1848

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
VARLEY, of Bury, in the County of Lancaster, Engineer, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Fourteenth day of August, in the twelfth year of Her reign, and
in the year of our Lord One thousand eight hundred and forty-eight, did, for
Herself, Her heirs and successors, give and grant unto me, the said John
Varley, Her especial license, full power, sole privilege and authority, that I,
the said John Varley, my exors, adñiors, and assigns, and such others ns I, the
said John Varley, my exors, adñiors, or assigns, should at any time agree with,
and no others, from time to time and at all times during the term of years
therein expressed, should aud lawfully might make, use, exercise, and vend, within
England and Wales, and the Town of Berwick-upon-Tweed, my Invention
of "CERTAIN IMPROVEMENTS IN STEAM ENGINES;" in which said Letters Patent
is contained a proviso that I, the said John Varley, shall cause a particular
description of the nature of my said Invention, and in what manner the same
is to be performed, to be enrolled in Her Majesty's High Court of Chancery,
within six calendar months next and immediately after the date of the said in
part recited Letters Patent, as in and by the same, reference being thereunto
had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
John Varley, do hereby declare that the nature of my said Invention, and
the manner in which the same is to be performed, is particularly described

page_text: and ascertained in and by the Drawings neret annexed, and the towing
explanation thereof (that is to say :)-
My improvements in steam engines are applicable to such stationary and
marine steam engines as have vertical stationary cylinders (that is, not oscil-
lating), whether the same be single cylinder engines or double cylinder engines.
My improvements consist in the mode of placing the steam and exhaust valves
of steam engines (either equilibrium or stalk valves) in the cover and bottom of
the cylinder, thereby avoiding the necessity of long passages between the valves
and the interior of the cylinder, which in ordinary engines causes a considerable
waste of steam at every stroke of the piston, and also diminishes the expansive
force of the steam exerted upon the piston. The use or adaption of my
Invention also supersedes the necessity for valve boxes and pipes in front of
the cylinder, thereby effecting a considerable economy in the first cost of the
engine, and also in the quantity of steam required. In order to illustrate more
fully the practical application of my Invention, and that the same may be more
minutely explained and easily understood, I have attached to these presents a
Sheet of Drawings representing in four views the application of Invention
my
to the cylinder of a stationary engine, and have marked the same with
figures and letters of reference corresponding with those in the following
description thereof :-
Fig. 1 in the Drawing represents a vertical section of a steam cylinder,
valves, and passages, and Fig. 2 is a front elevation of the same, shewing the
arrangement for working the valves and the method of connecting the same.
Fig. 3 is an horizontal section, taken through about the line A, B, in Fig. 1,
and Fig. 4 is a similar view taken through the line C, D, in the same Figure.
a, a, represents the steam cylinder; b, b, the piston, and c, c, the piston rod; d, d,
represents the steam or induction pipe; and e, e, the steam passages for both top
and bottom of the cylinder; f.f, is the exhaust or eduction pipe leading to the
condensor from the exhaust passage g, g; h, h', are the two steam valves, and i, i,
are the two exhaust valves; k, k, are small passages communicating with the
interior of the cylinder, in order to preserve the equilibrium of the valves. It
will be seen that by this arrangement of the valves and passages there is no
passage required between the valves and the interior of the cylinder, and con-
sequently a great saving in steam is effected. Upon referring to Fig. 2 in the
Drawing it will be seen that the steam valve h is connected to a vertical rod ?,
at the lower end of which is a friction roller running on the horizontal cam m,
the valve h¹ being connected to a lever l', also wrought by the same cam; the
two exhaust valves i, i, are both connected to one vertical rod n, n, to which
the requisite motion is imparted by means of the cam o; the cam m for admit-

page_text: ting steam is regulated by means of the rod p, connected to the governor.
By this arrangement it will be seen that only two cams are necessary to work
both steam valves and exhaust valves, instead of having four cams and four
rods, as heretofore.
Having now described the nature and object of my improvements, together
with the method of carrying the same into practical effect, I would remark, in
conclusion, that I desire it to be distinctly understood that I claim as my
Invention the novel and peculiar method shewn and above described of placing
the steam and exhaust valves of steam engines (either equilibrium or stalk
valves) in the cylinder cover and bottom, and also the method of connecting
and working the same.
In witness whereof, I, the said John Varley, have hereunto set my
hand and seal, this Thirteenth day of February, One thousand eight