Improvements in Steam Engines.
Year: 1890

page_text: Date of Application, 28th June, 1890
Complete Specification Left, 26th Mar., 1891-Accepted, 2nd May, 1891
PROVISIONAL SPECIFICATION.
Improvements in Steam Engines.
I, JOHN PITT BAYLY, of 18 Fulham Place, Paddington, in the County of
London, Patent Agent, (a communication to me from abroad by William Gehring,
of San Diego, California, U.S.A., Engineer,) do hereby declare the nature of this
invention to be as follows:-
By this invention, the steam cylinder is provided as usual, with a steam chest
having a valve seat and the usual inlet and exhaust ports. The valve-face of the
cylinder is provided on each side of the inlet ports with a cavity, and at each side of
these cavities with an aperture or port which extends through from near each end
of the steam chest to the interior of the cylinder. These two ports are cach fitted
with a mushroom valve which opens upwards towards the steam chest, is provided
with a stem projecting into the interior of the cylinder, and is kept closed by a
spiral spring arranged in the port. On each side of the two valve ports last named
are two small exhaust ports which extend through the bottom of the steam chest
into the cavities in the valve face of the cylinder. The bottom of the steam chest
extends only a short distance over the valve face of the cylinder, leaving sufficient
room for the travel of the slide valve. A piston is adapted to reciprocate within
the steam chest-which is preferably of circular diameter and which piston fits
the steam chest at its ends only, being hollow or reduced in diameter between its
extremities. The centre of the reduced portion of the piston is mortised to receive
projections upon the back of the slide-valve which rests upon the cylinder valve-
face. Exhaust ports are cut obliquely through the ends of the steam chest piston,
which, when the piston is at the end of its stroke open into the small exhaust ports
in the bottom of the steam chest.
When steam is admitted to the steam chest it enters one end of the cylinder by
one of the ordinary ports and forces the piston forward. Just before completing
its stroke, the piston-which has bevelled edges-comes into contact with and lifts
the stem of one of the mushroom valves aforesaid, and steam from the forward
end of the cylinder is admitted through the mushroom valve to one end of the
steam chest and forces the steam chest piston backwards together with the slide-
valve. The exhaust steam can then freely escape through the ordinary steam ports,
and live steam entering the forward end of the piston forces it backwards, and the
piston opening the other mushroom valve, admits steam from the rear of the piston
to the rear end of the steam chest and its piston which in moving causes the return
stroke of the slide-valve. The exhaust steam from the ends of the steam chest
escapes through the oblique ports in the ends of the piston, the small exhaust ports
in the bottom of the steam-chest, into the cavities in the valve-face of the cylinder,
and from thence into the ordinary exhaust port.
Datori this 28th day of June 1800.
J. P. BAYLY,
Applicant.
COMPLETE SPECIFICATION.
Improvements in Steam Engines.
I, JOHN PITT BAYLY, of 18 Fulham Place, Paddington, in the County of
London, Patent Agent, do hereby declare the nature of this invention (a commu-
nication to me from abroad by William Gehring, of San Diego, California, U.S.A.
Engineer,) to be as follows:-
Figure 1 is a side elevation of a steam cylinder with my improvement applied.

page_text: Fig. 2 represents a side and end elevation of the valve-operating piston.
Fig. 3 is a longitudinal section of the cylinder and valve-chest.
Fig. 4 is a longitudinal section of the tappet-valve casing.
Fig. 5 is a plan view of the same.
Fig. 6 is a longitudinal section of the tappet-valve casing.
Fig. 7 is a side elevation of the tappet-valve, and
Fig. 8 is a transverse section taken on line aa in Fig. 7.
Similar letters of reference indicate corresponding parts in all the views.
The object of my invention is to construct a steam-engine with automatic-valve
mechanism which will be operative without the use of an eccentric or crank.
My invention consists in the combination, with the steam-cylinder, of a steam-
chest containing a D valve, a piston adapted to move the D-valve, and tappet-
valves arranged to be operated by the power-piston so as to admit steam to the
space at the ends of the valve-operating piston.
The invention also consists in the combination with the valve and valve-operating
mechanism, of a starting-lever, all as will be hereinafter more fully described.
The cylinder A. is provided with a steam-chest B, which covers the valve-seat C,
and is provided with a cylinder D, in which slides the piston E. The valve-seat C
is provided with an exhaust-port F and with steam ports a a¹, which communicate
with the ends of the cylinder A.
To the valve-seat C is fitted a double main valve G, having the cavities bb, and
in the back of the said main valve G there is a cavity c for receiving the arm d, the
said arm d being mounted on the shaft e which extends through the side of the
valve-chest and is provided with a starting-lever H.
The piston E is provided with two heads ff, which move in the spaces 9 g', and
at the middle of its length is provided with a mortise h for receiving the rectangular
back of the main valve G.
.
In the heads ff¹ of the piston E are formed diagonal passages ii, through
which steam is admitted to the spaces g g¹ at the end of the steam-chest B.
In the lower part of the cylinder D are formed live-steam ports jj' and exhaust-
ports k k¹.
In the top of the cylinder A, underneath the rear ports k k', are inserted valve-
casings, provided with a valve-seat m, to which is fitted a tappet-valve n, which
is pressed to its seat by a spiral spring o, resting upon the valve and abutting
against the under surface of the valve-chest. The valve-casing extends into the
cylinder, the said casing communicating with the port a upon one end of the cylinder
and with the port a' at the opposite end. The valve-stem p of each valve n extends
into the path of the power-piston I, the said power-piston having beveled ends q for
engaging the valve-stems p as the piston nears the end of its stroke in either direction.
The operation of my improved valve-mechanism is as follows: Steam being
admitted to the steam-chest B, it passes underneath the valve G, through the
cavity b of the valve and port a of the cylinder into the back end of the cylinder,
pushing the piston forward. At the same time the used steam is passing out
through the port a¹ and cavity of the valve C into the exhaust port F, the
space at the ends of the valve operating piston E being filled with steam.
While the piston E is in this position steam is entering the space g at the opposite
end of the piston through the passage i and port j, thus practically balancing the
pressure upon the opposite ends of the piston E. Under these conditions the piston I
is moved forward, while the other parts of the engine are stationary; but when
the said piston
engages the stem p of the valve n at the forward end of the
cylinder it pushes the valve up, opening communication between the space g¹ and
the port a' through the casing and port k¹, thereby allowing steam to escape from
the said space g into the exhaust-port F through the port a' and cavity 6. At
this time the ports j¹ and i are closed. As soon as the pressure in the space g¹ is
less than that in the space g the expansion of the steam contained by the space g
forces the valve-operating piston E forward, shifting the valve G, so that live steam
is admitted through the cavity b' of the main valve and port a to the forward end

page_text: of the cylinder, thereby pushing the piston I toward the rear end of the cylinder.
As the piston E nears the end of its stroke the steam shut into the space g¹ by the
closing of the exhaust-port k by the piston itself arrests the motion of the piston,
and when the passage i and port j coincide live steam is admitted to the space g¹ ;
but, the pressure upon opposite ends of the piston E being practically equalized,
the said piston does not move until the power piston I nears the end of its rearward
stroke, when it engages the valve-stem p of the valve n at that end of the cylinder,
when the steam is allowed to escape from the space g, and what was described in
connection with the forward end of the cylinder now happens at the rear end of
the cylinder.
The engine is started by the admission of steam to the steam-chest and shifting-
valve G by means of the starting-lever H.
My improved valve mechanism for steam engines is particularly adapted for use
in connection with steam-pumps; but I do not limit or confine myself to this use of
my improvement.
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:
1. In a valve-operating mechanism for steam-engines, the combination, with the
cylinder and its piston, of the steam-chest B, provided with the valve-scat C, having
ports a a¹ F, and with the cylinder D, having the ports jj k k', valve-casings in the
top of the cylinder, under the ports k k and communicating with ports a a', spring-
pressed valves in said casings, the valve G, provided with cavities bb', and the
piston E, having ports in its heads and connected with the valve G, substantially
as described.
2. In valve-operating mechanism for steam-engines, the combination, with the
cylinder A and the steam-chest B, provided with the valve-seat C, and cylinder D,
having ports jj k k¹, of the main valve G, fitted to the seat C, the piston E, having
the mortise for receiving the back of the valve G and provided with the
passages i, the valve-casings 1, arranged to communicate with the exhaust-ports k k',
and with the ports a a', the spring-pressed tappet-valves n, contained by the
casings, and the power piston I, having beveled ends g, adapted to engage the
stems of the valves n, substantially as specified.
Dated this 26th day of March 1891.
J. P. BAYLY,
Applicant.