IMPROVE- MENTS IN APPARATUS FOR WORKING THE VALVES OF STEAM ENGINES
Year: 1860

page_text: LETTERS PATENT to George Tomlinson Bousfield, of Loughborough
Park, Brixton, in the County of Surrey, for the Invention of "IMPROVE-
MENTS IN APPARATUS FOR WORKING THE VALVES OF STEAM ENGINES."-A
communication from abroad by Edward N. Dickerson, of Park Row,
New York. United States of America.
PROVISIONAL SPECIFICATION left by the said George Tomlinson Bous-
Geld at the Office of the Commissioners of Patents, with his Petition,
on the 30th April 1860.
1. GEORGE TOMLINSON BOUSFIELD, of Loughborough Park. Brixton, in the
County of Surrey, do hereby declare the nature of the Invention for "IMPROVE-
MENTS IN APPARATUS FOR WORKING THE VALVES OF STEAM ENGINES," to be as
follows:-
The improvements consist in so operating the independent cut off valve of
marine engines (which as in common use is lifted and closed twice in each
revolution of the crank.) that in place of being closed by the motion of the
cam. it is detached from the lifting motion by means of a stop which disengages
the valve from the lifting apparatus at some point between the lifting cam and
the valve. when the same is used in combination with a plunger or piston
[Price 8d.]

page_text: attached to the closing valve falling into a vessel containing some fluid (liquid
or elastic) so constructed as to retard the fall sufficiently to prevent mischief
in the closing of the valve, by confining the fluid at or near the instant of
closing in a chamber below the piston or plunger.
For these purposes it is preferred to use a single poppet valve in the steam
chest leading to the slide valve chest of an ordinary marine engine. A slide
valve, or Cornish or other valve, may be used if preferred. On the main shaft
there is a cam which acts twice in each revolution upon a roller on the end
of a lever as usual. in similar arrangements, although the roller may be
mounted in a carriage, and made to ride upon the cam, and left perpendi-
cularly, which is the better way for oscillating cylinder engines. This lever
gives motion to a bell-crank, which transfer the motion of the cam to the valve
in the steam chest by a catch which lifts the valve by its stem. This catch or
latch moves on an axis at one end of the bell crank, and is pressed into place
by a spring. On the catch or latch there is a swell or projection which, as
the latch rises, comes against a roller, and by this means the latch is disengaged
from the stem of the valve. This roller is carried on the end of a lever, and
may be set in any position by the engine driver by a suitable handle so
as to cut off the steam sooner or later in the stroke of the engine, as may be
desired.
+
The vessel containing fluid to act as a cushion to arrest the fall of the
valve, is formed with a contracted circular chamber at its lower end, into
which the lower end of a plunger fits. The plunger works in this vessel
through a stuffing box, and the plunger is attached to the valve stem so as to
rise and fall with it in such manner that the valve may come to its seat at
the same time that the lower end of the plunger enters the chamber of the
vessel, and shuts in the fluid which it contains. so that the plunger is retarded
in its descent by the impenetrability of the fluid thus confined.
By the use of this machine the cut-off valve may be closed twice in each
revolution with immense velocity, and yet without concussion or injury to the
machinery, while at the same time the point of cut off may be regulated at
pleasure so as to carry steam to the best advantage.
I would state that the arrangement of the apparatus above described may
be varied, but that the peculiarity of the Invention consists in the combination
of a cam for opening the cut-off valve of steam engines twice at each stroke
of the engine with a detaching apparatus for liberating the valve from the
opening motion, so that it may close by the force of a weight or spring. and
with a plunger or piston connected with the closing valve so operating as to
arrest the rapid motion of closing at the end of its action, by confining some

page_text: fluid beneath it, or in a close chamber sufficiently to arrest the high motion of
closing in time to prevent injury or concussion to the machinery, substantially
as described.
SPECIFICATION in pursuance of the conditions of the Letters Patent. filed
by the said George Tomlinson Bousfield in the Great Seal Patent Office
on the 30th October 1860.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
TOMLINSON BOUSFIELD, of Loughborough Park, Brixton, in the County of
Surrey, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirtieth day of April. in the year of our Lord
One thousand eight hundred and sixty, in the twenty-third year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said George Tomlinson Bousfield, Her special licence that 1. the said
George Tomlinson Bousfield, my executors. administrators, and assigns, or
such others as 1. the said George Tomlinson Bousfield, 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 "IMPROVEMENTS IN APPARATUS FOR WORKING
THE VALVES OF STEAM ENGINES," a communication to me from abroad by
Edward N. Dickerson, of Park Row. New York, United States of America,
upon the condition (amongst others) that 1, the said George Tomlinson
Bousfield, my executors or administrators, 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 George Tomlinson Bousfield, do
hereby declare the nature of the said Invention, and in what manner the
same is to be performed. to be particularly described and ascertained in
and by the following statement thereof. that is to say:
The improvements consist in so operating the independent cut-off valve of
marine engines (which as in common use is lifted and closed twice in each

page_text: revolution of the crank) that in place of being closed by the motion of the
cam, it is detached from the lifting motion by means of a stop which dis-
engages the valve from the lifting apparatus at some point between the lifting
cam and the valve, when the same is used in combination with a plunger or
piston attached to the closing valve falling into a vessel (containing some fluid,
liquid, or elastic) so constructed as to retard the fall sufficiently to prevent mis-
chief in the closing of the valve by confining the fluid at or near the instant of
closing in a chamber below the piston or plunger.
In the accompanying Diagram. F is a single poppet valve, which is best
in the steam chest leading to the slide valve chest of an ordinary marine
engine. A slide valve, or Cornish or other valve, may be used if preferred.
A is the main shaft, with a cam which lifts the roller B twice in each revo-
lution; C is a lever as usual in similar arrangements. The roller may be
mounted in a carriage, and made to ride upon the cam, and lift perpendi-
cularly, which is the better way for oscillating cylinder engines. D is a bell
crank to transfer the motion of the cam to the valve; E is a catch which
lifts the valve by its stem M. This catch or latch is centred at N, and is
pressed into place by a spring: H is a roller, which is pressed against by the
swell L on the latch as it rises, and by means of which the latch is disengaged.
This roller may be set in any position by the engine driver by the handle J
so as to cut off sooner or later in the stroke as may be desired. G is a vessel
containing the fluid to be used as a cushion to arrest the fall of the valve,
and it has a contracted circular chamber at its lower end O, into which the
lower end of the plunger K fits exactly; K is the plunger working into this
vessel through a stuffing box. and attached to the valve stem so as to rise and
fall with it by means of jam nuts at P. which are to be so set upon the valve
stem as that the valve may come to its seat at the same time that the lower
end of the plunger K, enters the contracted chamber of the vessel G. and
shuts in the fluid which it contains, so that the plunger is retarded in its
descent by the impenetrability of the fluid thus confined.
By the use of this machine the cut-off valve may be closed twice in each
revolution with immense velocity, and yet without concussion or injury to the
machinery, while at the same time the point of cut off may be regulated at
pleasure so as to carry steam to the best advantage without trouble.
The Diagram illustrates the principle of the mechanism, but the details
will differ with the different forms and arrangements of engines to which the
same is applied, but an engineer will readily adapt it to each case. The valve
gear may be made to lift during the entire stroke of the engine instead of
about three-quarters as shown, and two latches may be used instead of one,

page_text: so that one shall lift the valve at each stroke instead of using one to lift at both
strokes. I would state that I make no claim to any of the parts saparately,
but what. I claim is the combination herein described.
In witness whereof. I, the said George Tomlinson Bousfield. have here-
unto set my hand and seal, this Twenty-ninth day of October, in the
year of our Lord One thousand eight hundred and sixty.