IMPROVEMENTS IN VALVES FOR STEAM, GAS, AND AIR ENGINES
Year: 1879

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields, in the
County of Middlesex, Gentleman, for the Invention of "IMPROVEMENTS IN
VALVES FOR STEAM, GAS, AND AIR ENGINES." A communication from abroad
by Francis Winters, of the City, County, and State of New York, United
States of America.
Sealed the 14th May 1880, and dated the 22nd December 1879.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at the
Office of the Commissioners of Patents on the 22nd December 1879.
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman. "IMPROVEMENTS IN VALVES FOR STEAM, GAS, AND AIR ENGINES."
A communication from abroad by Francis Winters, of the City, County, and State
of New York, United States of America.
This Invention relates to a hollow, cylindrical, and chambered valve contained in
a casing or chest, and rotated by and in unison with the crank shaft of a steam,
gas, or air engine, the said valve having two sets of ports and being adjustable
longitudinally, so that one or other of the two sets of ports may be brought into
action, or both be placed out of action, as the stopping, starting, and reversing of
the engine may require.
The main object of the Invention is to maintain the valve tight against its seat
in the casing under all circumstances, and this object is effected by applying the
steam to the exterior of the valve and exhausting through the same, and by causing
the steam at the entrance to the casing to force a piston against the valve, and
consequently to force the valve itself against its seat in the said casing.
The details of the Invention may be arranged in various ways without departing
from its principle, but the following arrangement of the parts is found convenient
in practise:-
From the valve chest or casing made in the form of a hollow cylinder projects at
any suitable point (say, for example, at the centre), a cylindrical branch containing
a piston which is connected to a smaller piston, the latter being adapted to a
cylinder secured to or forming part of the valve cylinder. Steam is admitted to
the space between the two pistons, and thence through an opening in the larger
[ Price 6d 1

page_text: piston, and thence to the interior of the valve, when a part of the latter coincides
with the said opening.
The area of the larger piston is so much in excess of that of the smaller piston
that the former will always be forced by the steam against the cylindrical valve,
and the latter against that portion of the interior of the casing where the ports
communicating with the engine cylinder occur.
The steam is exhausted through the valve at both ends of the same, and escapes
through passages formed in or near the covers at each end of the chest or casing,
and through any suitable exhaust pipes communicating with the said passages.
A rod is secured to each end of the valves and passes through a stuffing box in
the cover of the casing.
One end of the rod is connected by suitable apparatus to stopping, starting, and
reversing mechanism, by which the valve may be adjusted to either of the three
positions hereinafter explained, and the rod and valve are rotated from and in
unison with the crank shaft of the engine through the medium of any suitable
groove. When the valve is in such a position that no port coincides with the
opening in the larger piston no steam can be admitted, and consequently the
engine is stopped. When however the valve has been moved longitudinally in one
direction to a given extent two ports will as the valve rotates be brought alternately
opposite the opening in the larger piston, the said ports respectively communicating
through passages in the valve with other ports, so arranged in respect to the
opening of the piston and to the two ports communicating with the engine cylinder
on opposite sides of the piston that as the valve rotates the steam will be directed
first to one port of the latter and then to the other. While however the steam is
being directed to the cylinder on one side of the piston it is exhausted from the
opposite side, and this exhausting may be effected in the following manner :-
Depressions are formed in the valve communicating through openings with an
exhaust chamber contained in the interior of the valve, and open at both ends of
the same, this chamber being separated by suitable partitions from the steam
chamber previously referred to. As the valve rotates one of these depressions 18
brought opposite one of the ports of the engine cylinder, and the steam at that end
of the cylinder is exhausted through the valve and passages in like manner. When
the other depression is in its turn brought opposite the other port of the engine
cylinder the steam is exhausted from the opposite end of the cylinder into the
central chamber of the valve.
In order to reverse the movement of the engine the valve is moved longitudinally
in a direction contrary to that previously assumed, whereby the valve ports before
referred to become out of action and a new and independent set of ports is brought
into action, the latter being arranged in such relation to each other and to the
opening of the piston and the cylinder ports that a reversal of the motion of the
engine must necessarily take place.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Henry Johnson in the Great Seal Patent Office on the 20th
May 1880.
33
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman. "IMPROVEMENTS IN VALVES FOR STEAM, GAS, AND AIR ENGINES.'
A communication from abroad by Francis Winters, of the City, County, and
State of New York, United States of America.
The said Invention relates to improvements in cylindrical valves for steam, gas,
and air engines, the improvements being especially applicable to a hollow, cylindrical,
chambered valve contained in a casing or chest, and rotated by and in unison with
the crank shaft of a steam, gas, or air engine, the said valve having two sets of
ports and being adjustable longitudinally in its chest, so that one or other of the
two sets of ports may be brought into action, or both out of action, as the stopping,
starting, and reversing of the engine may require.
The main object of the said Invention is to maintain the valve tight against its
seat in the casing under all circumstances, and this object is attained by admitting
the steam to the exterior of the valve and exhausting through the same, and by
causing the steam at the entrance to the casing or chest to force a piston against
the valve, and consequently to force the valve itself against its seat in the said
chest.
And in order that the said Invention may be fully understood I shall now
proceed more particularly to describe the same, and for that purpose shall refer to
the several Figures on the annexed Sheet of Drawings, the same letters of reference
indicating corresponding parts in all the Figures.
Figure 1 of the accompanying Drawing is a sectional elevation illustrating the
application of the Invention to a valve with duplex system of ports and valve
chest.
Figures 2, 3, 4, 5, 6, and 7 are transverse sections of the valve, taken respectively
along the lines 1, 1,-2, 2,-3, 3,—4, 4,—5, 5, and 6, 6; and
Figures 8 and 9 are similar views to Figure 1 of the valve and chest, but showing
the former in different positions.
B is the valve, adapted to the valve chest or casing A, the latter being made in
the form of a hollow cylinder, from which at a central point projects a cylindrical
branch a containing a packed piston b, which is connected by rods to a smaller
piston c adapted to a cylinder d, secured to or forming part of the cylinder a.
Steam is admitted through a branch e to the space between the two pistons,
and thence through a central opening f in the larger piston b to the interior of the
valve B, when a steam port of the latter coincides with the said opening f.
In Figure 1 there is no port to receive the steam from the said opening, for the
reason that in that view the valve has been adjusted to a position which determines
the stoppage of the engine, as will be hereinafter explained.
The area of the piston b is so much in excess of that of the piston c, the upper
surface of which is exposed to the atmosphere, that the said piston b will always
be forced against the surface of the valve, and the latter against that portion of the
interior of the casing where the ports m, m', communicating with the interior of
the cylinder of the engine occur. The smaller cylinder & and its piston c may be
dispensed with, and the top of the branch a of the steam chest closed, in which
case there will always be a pressure of steam on the piston b, but the arrangement
above described is performed.
This feature of the said Invention may be applied to ordinary cylindrical valves.
The steam is exhausted from the cylinder of the engine through the valve and
escapes at both ends of the same, and thence through passages n, n, formed in the

page_text: present instance in the covers W, W, secured to the ends of the cylindrical chest A,
these passages communicating with suitable exhaust pipes.
A. valve rod C passes through and is secured to the valve B, and also passes
through stuffing boxes in the covers W, W, of the valve chest, the end of the rod
being connected by suitable appliances to stopping, starting, and reversing mechanism,
by which the said valve may be adjusted longitudinally in its chest to either of the
three positions hereinafter explained, and the rod and valve being rotated from and
in unison with the crank shaft of the cugine.
As before remarked when the valve is in the position shown in Figure 1, where
it is midway between the limits of its movements in both directions, no steam can
pass from the opening fin the piston b to the interior of the valve, for the reason
that while the valve is in this position no ports are presented to the said opening f,
but when the valve has been moved longitudinally in its chest in the direction of
the arrow, Figure 1, to the position shewn in Figure 8 two ports h, h¹, Figure 5,
will as the valve rotates be brought alternately opposite the opening f in the
piston b, one of these ports communicating through a passage in the valve with a
port i, Figures 3 and 8, and the other through another passage in the valve with
a port i, Figures 7 and 8, in the same, these two ports i, i bearing such relation to
each other and to the ports m, m³, of the steam cylinder that as the valve rotates
steam will be directed first to the cylinder on one side of the piston and then to 2
the cylinder on the opposite side of the piston. But while the steam is being
directed to the cylinder on one side of the piston it is being exhausted from the
opposite side in the following manner :-
There is in the valve a depression j, Figures 7 and 8, which communicates
through a port with an exhaust chamber within the valve and extending entirely 2
through the same, this exhaust chamber being separated by suitable partitions from
the steam chamber previously referred to. There is a similar depression j', Figures
3 and 8, in the valve near the opposite end of the same, and as the valve rotates
these depressions during a portion of the valve's revolution are brought opposite
the ports m, m³, of the cylinder. These exhaust depressions and ports bear such 3
relation to cach other, to the above described steam ports, and to the ports m, m³,
of the cylinder, that while steam is admitted through one of the latter ports to the
cylinder on one side of the piston steam will be exhausted through the other port
and through the valve from the opposite side of the piston.
When the valve has to be reversed it must be moved to the position shown in 3
Figure 9, when the valve ports above referred to, and shown in Figures 3, 5, and 7,
will be entirely out of action and a new set of steam ports and exhaust ports in
the same valve, and shown in Figures 2, 4, and 6, will be brought into play, these
ports being precisely similar to those described above but differently arranged, so
that they will perform their duties properly when the rotary motion of the valve is
secured with the reversal of the engine.
The new set of steam admission ports in the valve aro indicated by the letters
w, w¹, in Figures 4 and 9; the new set of steam outlet ports by the letters x, x³,
Figures 2 and 6; and the new sets of exhaust depressions and ports by the letters
y, y', Figures 2 and 6; and the relation of these ports to those first referred to will
be understood by comparing the sections Figures 2, 4, and 6, with the sections 3, 5,
and 7.
The mode of so partitioning the intorior of the valve as to separate the exhaust
passages from the steam passages will be readily understood by perusing the views
2 to 7 inclusive and comparing them with the other views.
I am aware that it has been previously proposed to make a rotary, cylindrical,
and longitudinal adjustable valve with two sets of steam and exhaust ports, for
the purpose of stopping, starting, and reversing an engine, but in that case steam
was introduced into the valve at one or both ends of the same and exhausted through
the sides, a plan which rendered the maintenance of the valve tight in the chest 5
almost impossible. By introducing the steam into the sides of the valve and

page_text: exhausting it through the ends of the same I am enabled to keep the valve tight
to its seat, and this tightness is enhanced by the pressure of steam on the piston b.
The Invention is especially adapted to air engines in which great pressure is
used, and in which great difficulty is experienced in keeping the valves tight.
Having now described and particularly ascertained the nature of the said
Invention, and the manner in which the same is or may be used or carried into
effect, I would observe in conclusion that what I consider to be novel and original,
and therefore claim as the Invention secured to me by the herein before in part
recited Letters Patent is,-
First. A rotating and longitudinally adjustable valve having duplex ports and
passages, arranged substantially as set forth, in combination with a chest having
an inlet for the admission of steam to the exterior of the valve, and having ports
m, m³, through which steam may be admitted to the cylinder, and exhausted there-
from through the valve, all substantially as hereinbefore described.
Second. The combination of a cylindrical valve and its casing or chest with a
piston bearing against the side of the valve, and arranged to be exposed to the
pressure of steam, substantially as hereinbefore described.
In witness whereof, I, the said John Henry Johnson, have this my Specifica-
tion set my hand and seal, the Thirteenth day of May, One thousand eight
hundred and eighty.