Steam or other Engines at or from any Point.
Year: 1886

page_text: Steam or other Engines at or from any Point.
We, HAVELOCK HARFORD, Engineer, of 6 Victoria Terrace, and CHARLES
FREDERICK SUTCLIFFE, Surgeon Dentist, of 5 Ocean Road, South Shields, in
the County of Durham, do hereby declare the nature of this invention to be as
follows:-
Our invention relates to an arrangement of the valves for admitting steam-or
other motive power-to and releasing it from the cylinder by means of which an
engine may be instantly reversed and caused to run in the opposite direction
without the intervention of any form of reversing gear beyond that which changes
the relative positions of the valves and ports. It is applicable to any type of
engine, in modified forms, and consists essentially in providing a cylindrical valve
working in a chamber (which may in some cases be slightly tapered) between the
valve face of the cylinder and the cylinder itself having its axis parallel to that of
the cylinder and preferably situated to one side of the ports in valve face. This
intermediate valve, which we term the reversing valve, may be fitted with packing
rings and may fit the chamber its whole length or only at intervals to diminish
friction. There are 4 ports in the main valve face which are alternately steam and
exhaust ports and one central main exhaust port.
The cylindrical reversing valve has also 4 ports in it corresponding with the
4 ports in valve face but the 2 end ports are diametrically opposite the other 2 and
both ports at each end open into the steam passages of cylinder, none of the ports
having any communication with the central main exhaust port in valve face
except through the valve. The main valve which may be of the slide, piston or
other suitable type has 4 ports in its face 2 only of which (forming steam ports)
open through it and one large central exhaust port into which the other 2 ports of
valve open and it is worked by a single eccentric set at right angles with the
crank and in advanco thereof when running ahead. The valve has thus no "lap"
with reference to the position of the eccentric nor any "lead" which however is
provided on the valve itself and regulated by an expansion slide or valve.
When (for example)-the engine is running ahead steam is admitted by main
valve through the end steam ports in valve face and enters the cylinder through
the end ports in the cylindrical valve, exhausting from the cylinder through these
latter ports and the exhaust ports of main valve into the central exhaus cavity

page_text: and so to atmosphere, condenser or into another cylinder as the case may be. If
now it is desired to reverse the engine the cylindrical valve is rotated on its axis
one half turn which brings the other ports opposite the other 2 ports in valve
face and thus the steam side of piston is made the exhaust side, steam is admitted
to the opposite side of piston and the engine continues to run astern until it is
desired to again reverse the motion. In ordinary high pressure or condensing
engines it will be generally necessary to use an expansion valve on back of main
valve in order to get "lead" to start the engine and this valve can be worked
by an eccentric at 45° behind the crank when going ahead-In compound engines
the cylindrical reversing valve will be preferably applied to the low pressure
cylinder, no expansion valve being required a good opening being obtained and
steam carried to nearly the end of stroke with a quick cut off and the full benefit
of the vacuum in reversing. The reversing valve can be rotated by a spindle with
handle brought to a convenient position and has no wear and tear as it is stationary
when not required to be used. The engine can be reversed at any point of stroke
without auxiliary starting gear and without the intervention of a reversing link or
equivalent gear. In condensing engines the vacuum is preserved which is a great
advantage in steamers working into docks or alongside quays.

page_text: Steam or other Engines at or from any Point.
We, HAVELOCK HARFORD, Engineer, of 6 Victoria Terrace and CHARLES
FREDERICK SUTCLIFFE, Surgeon Dentist of 5 Ocean Road South Shields in the
County of Durham 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:-
Our invention relates to an arrangement of the valves for admitting steam-or
other motive power, to, and releasing it from, the cylinder by means of which an
engine may be instantly reversed and caused to run in the opposite direction with-
out the intervention of any form of reversing gear beyond that which changes the
relative positions of the valves and ports. It is applicable to any type of engine in
modified forms but is specially adapted for small high speed engines of launches,
torpedo boats and similar craft and consists essentially in providing a cylindrical
valve working in a chamber (which may in some cases be slightly tapered) between
the valve face of the cylinder and the cylinder itself, having its axis parallel to
that of the cylinder and, preferably, situated at one side of the ports in valve face,
This intermediate valve, which we term the reversing valve, inay be fitted with
packing rings and may fit the chamber its whole length or only at intervals to
diminish friction. There are four ports in the main valve face, which are alternately
steam and exhaust ports, and one central main exhaust port.
The cylindrical reversing valve has also four ports in it, corresponding with the
four ports in valve face but the two end ports are diametrically opposite the other
two and both ports at each end open into the steam passages of cylinder none of
the ports having any communication with the central main exhaust port in valve
face except through the valve. The main valve, which may be of the slide piston
or other suitable type, has four ports in its face two only of which (forming steam
ports) open through it and one large central exhaust cavity into which the other
two ports of valve open and it is worked by a single eccentric set at right angles
or ninety degrees with the crank and in advance or behind it, according to the
form of valve used, when running ahead. By an error in provisional specification
the main eccentric was described as being in advance of the crank when running
ahead instead of behind it as it must be with the form of main valve shewn on the
accompanying drawings. The valve has thus no "lap" with reference to the
position of the eccentric nor any "lead" which however may be provided on
the valve itself by shortening its covering edges and regulated by an expansion
slide or valve.
When (for example) the engine is running ahead steam is admitted by main.
valve through the end steam ports in valve face and enters the cylinder through.
the end ports in the cylindrical valve exhausting from the cylinder through these
latter ports and the exhaust ports of main valve at opposite end into the central,
exhaust cavity and so to atmosphere, condenser or into another cylinder as the case

page_text: The accompanying drawings illustrate our invention applied to one cylinder of
an inverted engine which cylinder may be high pressure, condensing or any one
cylinder of a series as of compound engines.
Figure 1 is a vertical section taken purposely for clearness through the angular
line A B C D on Figure 2 which is a plan in section through the line E F of
Figure 1 in which the engine is running "ahead "-Figure 3 is a section on same
line as Figure 1 with the reversing valve moved on half round to cause the engine
to run "astern."
On all the Figures the same numerals indicate corresponding parts and only
those portions of the engine are shewn which are necessary to illustrate the
invention.
(1) is the cylinder with steam chest (2) cast upon it and having between it and
the main port face (3) à cylindrical cavity (4) formed in it to receive the reversing
valve (5) in which are four ports (6 62) and (7 7*) the two ports (77) being
opposite to (6. 6) and all lead into passages opening through the ends of the
valve (5). In the main face are also four ports (8 8°) and (8b, 8°) corresponding
with those in the valve (5) and a central exhaust cavity (9) leading into the
belt (10) but with no direct communication with the valve (5). The form of
main valve (11) shewn is convenient for applying on its back the expansion
valve (12). In the position shewn on Figure 1 the engine is running ahead the
piston moving downward having travelled beyond half stroke the main valve (11),
moving also downward, not having closed the upper port (8) but the expansion
valve (12)-having previously shut off the steam while the lower port 8* is still well
open to the exhaust which passes by pockets (13) (shewn on Figure 2) round the
steam passage in main valve, the directions of the steam and exhaust being indi-
cated by arrows. If now the reversing valve (5) is moved on its axis one half
turn the relative positions of the ports is as shewn by Figure 3 in which the ports
(8 and 8) in face are closed and the ports (8b and 8°) opened admitting steam to
opposite sides of piston through the port (7*) in valve (5) while the port (8b) is
opened to port (7) in valve (5) and the steam exhausts from top of piston through
the main valve, and into the cavity (9) as indicated by the arrows, the engine now
running "astern "-By a movement of the valve (5) on its axis through only one
quarter turn both steam and exhaust ports are closed the steam contained in the
'

page_text: cylinder being compressed by the piston tending to bring the engine to rest.
With this form of main valve the main eccentric will be 90° behind the crank
when running ahead, the expansion eccentric being 45° behind the crank, but with
an ordinary single or double ported main valve their positions will be corre-
spondingly adjusted. The required "lead" can be obtained by shortening the
covering edges of the main valve, or generally the angularity of the eccentric
rod will sufficiently give the small opening required.
The reversing valve (5) is turned on its axis by a handle on end of its spindle
which may be carried by a bracket at a convenient position on starting platform.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is
The application to steam or other engines of a valve, interposed between the
main valve and the cylinder, by means of which the engine may be stopped,
started or reversed at or from any point, constructed and operating substantially
as described and shewn.