Improvements in Steam Engines.
Year: 1892

page_text: Date of Application, 24th Oct.. 1892
Complete Specification Left, 10th July, 1893-Accepted, 12th Aug.. 1893
PROVISIONAL SPECIFICATION.
Improvements in Steam Engines.
1 WILLIAM CRAVEN of Smedley House, Smedley Lane, Manchester in the
County of Lancaster, Engineer, do hereby declare the nature of this invention to
be as follows:-
My said invention relates to improvements in the construction of steam engines
and has for its chief object the minimising of the initial condensation of steam
which occurs owing to the difference of temperature between the steam admitted to
the cylinder and that of the inner surface of the cylinder itself.
Hitherto the normal speed of steam engines has been controlled by means of a
valve between the cylinder and the source of the steam supply for the purpose of
varying the admission of steam to the cylinder to suit the varying load or work the
engine has to perform, a governor or other suitable means being employed for
operating the said valve.
According to my said invention I control the speed of a steam engine by varying
the rate of exit of the steam from the exhaust side of the piston by providing
suitable valve gear preferably operated automatically by a governor in such a
manner that when the speed of the engine increases the piston will be cushioned
by the area of the outlet for the exhaust steam being contracted and that when
the load of the engine is increased the area of the said outlet will be increased and
the back pressure correspondingly decreased.
By this means the access of cold air to the interior of the cylinder is prevented,
the temperature of the walls of the cylinder is kept more uniform and partial
condensation of the steam at the commencement of each admission to the cylinder
is lessened.
Dated this 21st day of October 1892.
EDWARD TURNER WHITELOW,
70, Deansgate, Manchester, Agent for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Steam Engines.
I WILLIAM CRAVEN of Smedley House, Smedley Lane, Manchester in the
County of Lancaster, 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 said invention relates to improvements in the construction of steam engines
and has for its chief object the minimising of the initial condensation of steam
which occurs owing to the difference of temperature between the steam admitted to
the cylinder and that of the inner surface of the cylinder itself.
Hitherto the normal speed of steam engines has been controlled by means of a
valve between the cylinder and the source of the steam supply for the purpose of
varying the admission of steam to the cylinder to suit the varying load or work the
engine has to perform, a governor or other suitable means being employed for
operating the said valve.
According to my said invention I control the speed of a steam engine by varying
the rate of exit of the steam from the exhaust side of the piston by providing a
suitable valve or valves operated automatically by a governor in such a manner
that when the speed of the engine increases the stroke of the piston will be
impeded by the area of the outlet for the exhaust steam being contracted and that
Price Sl

page_text: when the load of the engine is increased the area of the said outlet will be increased
and the back pressure on the piston be correspondingly diminished.
By such an arrangement of the valve or valves the access of cold air to the
interior of the cylinder is prevented, the temperature of the walls of the cylinder is
kept more uniform and partial condensation of the steam at the commencement of
each admission to the cylinder is lessened.
I wish it to be understood that I do not limit myself to any particular form or
construction of valve for varying the area of the exhaust outlet inasmuch as any
type of valve working in equilibrium or so far balanced as to be capable of being
operated by the governor may be used.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed I declare that what I
claim is―
In a steam engine the use in combination with a governor of a valve for
augmenting or diminishing the area of the aperture or apertures through which the
exhaust steam escapes for the purpose of controlling the speed under varying loads
substantially as hereinbefore set forth.
Dated this Eighth day of July 1893:
EDWARD TURNER WHITELOW,
70, Deansgate, Manchester, Agent for the Applicant.