IMPROVEMENTS IN STEAM OR AIR SLIDE VALVES, CYLINDERS AND PISTONS APPLICABLE FOR ALL CLASSES OF ENGINES
Year: 1885

page_text: 6133
Effected without Link Motion or other Gear.
I GEORGE THOMAS PARNELI. of 22 Charing Cross in the City of Westminster,
Engineer do hereby declare the nature of my invention for IMPROVEMENTS IN
STEAM OR AIR SLIDE VALVES, CYLINDERS AND PISTONS APPLICABLE FOR ALL
CLASSES OF ENGINES, to be as follows:-
The principle of this invention consists of a Slide Valve, Cylinder and Piston
capable of reversing Engines without link motion or other gear of any kind as now
used for that purpose. The Valve can be actuated by either Air steam or water.
The Valve is formed with Cylindrical ends coned on the inside at each end and
curved centre face with an open back to receive the power for admission to the
Main Cylinder and is recessed and divided in front or face for both the live power
and exhaust. The Valve is turned and fitted to a case with two Covers. The Case
is constructed with live power and exhaust ports for controlling and working the
Valve and to admit the power to the Main Cylinder and Piston. The valve is
fitted upon a bar running through the Case Valve and Covers and provided with a
feather key for the Valve.
The Cylinder is constructed with portways passages and recesses running from
the Centre and is planed to receive the Valve Case which is secured by studs or
bolts to the face of Cylinder. The Piston is recessed in the centre between two
heads to suit the portways passages and recesses in Valve Case and Cylinder and is
made of wrought or cast metal and is fitted with a piston rod and with two or
more rings.
The Valve as shown in Case on Figure 1 Section A of drawing is placed in Mid
Centres of the Case so as to cover the main portways running to each end of the
Main Cylinder, and when at work this position of the Valve would be the time
when the Valve is exhausting.
The Piston as shown in Main Cylinder also on Section A of the Drawing is
placed in Mid Centres of Main Cylinder and has the two controlling portways
within the recess of piston and when at work this position of the piston would be
the time when the Cut off takes place in the stroke.
The next point in this invention is that when the piston has advanced further
so as to cover one controlling portway the Valve is then drawn over to the end of

page_text: Case in the opposite direction to the travel of piston in readiness to admit the live
power into the Main Cylinder for the return stroke of the piston.
The Valve Case has two relieving portways for the Valve and these portways
lead to each end of the Case and thence into the Main Cylinder by corresponding
openings and by this means the exhaust is conveyed into the Main exhaust port by
the half Circle recess in the piston and through the openings in the side of Main
Cylinder. The Valve Case has also a regulating groove at each end for con-
densation purposes.
To operate. the Engine the steam Air or Water is turned on and the piston is
caused to make a slight movement which regulates the Valve for the distribution
of power through the main supply port at one end of the Cylinder. The piston
then travels till it closes the exhaust at one end of the Valve Case and opens the
connection for the exhaust at the other end of Case; this in turn causes the
Valve to return to the opposite end of the case and admit the power into
the opposite end of Main Cylinder and continue the motion of the Engine.
I claim for my invention the construction and design of Valve and Case in which
it moves and Main Cylinder with portways passages and recesses and piston
and the means of reversing Engines without link motion or other gear and
arrangement for controlling the Valve and actuating same without gear.
Effected without Link Motion or other Gear.
I, GEORGE THOMAS PARNELL, of 22 Charing Cross, in the County of Middlesex,
Engineer, do hereby declare the nature of said invention for IMPROVEMENTS IN
STEAM OR AIR SLIDE VALVES, CYLINDERS, AND PISTONS, APPLICABLE FOR ALL
CLASSES OF ENGINES, WHEREBY THE REVERSING OF ALL STEAM, OR OTHER FLUID
PRESSURE ENGINES, IS EFFECTED WITHOUT LINK MOTION OR OTHER GEAR, and in
what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement, reference being had to the accom-
panying drawings, and to the letters and figures marked thereon, that is to say :-
My Invention relates to improvements in steam or air slide valves, cylinders, and
pistons, applicable for all classes of engines, whereby the reversing of all steam, or
other fluid pressure engines, is effected without link-motion, or other gear, and it
consists :-
1. Of an inverted slide valve, with circular ends and case complete in itself, as
hereinafter described.

page_text: 2. Of a cylinder, and recessed piston each complete in itself, but both being
required in one operation of work, as hereinafter described.
According to my Invention, the valve is formed in one piece, with inverted
centre and circular ends, and is provided with grooves to suit the ports in the case,
and with faces to cover and uncover the said ports. The circular ends are turned
to fit the case, and are fitted upon a steel bolt or bar passing through the entire
length of the valve and case. The steel bolt or bar has a feather fitted through its
entire length. The valve is grooved for a feather way to prevent it turning round
in the case, when at work. The valve case has seven ports, two of which control
the valve movement when at work, two for adjustment ports, two to admit steam
to main cylinder, and one for exhaust. The case is fitted with two covers, one at
each end, through which the steel bolt or bar passes, on which the valve is fitted,
and are drawn firmly together by means of a nut on one end of the steel bolt or
bar. The valve case is adjusted to the face of the cylinder, which is planed to
receive same, and secured by four studs and nuts.
The main cylinder is bored parallel, and has a cover fitted to each end, with a
stuffing box and gland, through which the piston rod passes. This cylinder has
seven ports, two of which have tubes firmly fitted air tight through the main steam
ports, from the face on which the valve case is adjusted, into the inside of the
cylinder. These two ports are for the purpose of actuating the valve in the case,
two others are for the purpose of admitting the live power into each end of the
cylinder, two for the exhaust of the valve, and one for the exhaust of the main
cylinder.
This
The piston is a hollow one, and is formed with a recess on its outer surface, for
half its circumference, and is fitted on a steel piston rod, with cone and nut.
recess in the central portion of the exterior of the piston is so arranged as to cover
and uncover the adjusting and controlling ports in the valve case.
For the operation and movement of the valve and piston, the steam, or air, is
admitted into the valve case, and through the open ports into the cylinder, causing
the piston to move forward, which opens the main supply port at the end of the
receding piston, at the same time freeing the opposite end of the cylinder and
This movement of
closing the opposite exhaust port leading into the valve case.
the piston gives freedom to the controlling port from the valve case to cylinder,
which, in consequence, causes the valve to travel to the other end of the case and
exhaust. The steam being then admitted to the other end of the cylinder, the
piston making the return stroke, frees the opposite end of the cylinder and closes
the second exhaust port in the valve case, and frees the second controlling port in
t the valve case. The valve then travels to the opposite end of the case and
exhausts, thus continuing the motion of the engine.
Both the valve and main cylinder have independent exhausts. None of the live
power is expended in moving the valve, it being moved and controlled by the
exhaust alone, with the aid of the recess in the centre of the piston. Thus a great
saving is effected in that point alone, and absolute certainty of the action of the
valve is obtained, which is of the utmost importance in high piston speeds and
heavy pressures.
By this arrangement of valve and cylinder, all springs, eccentric sheaves,
eccentric straps, slide rods, guides, and other appliances are entirely dispensed with,
and the action of the valve made purely automatic, it being actuated and controlled
by the several ports in the valve case and main cylinder, together with the
movement of the piston in the main cylinder.
And in order that my Invention may be readily understood, I proceed to
describe the same with reference to the accompanying drawings, in which:
Fig. 1, is a longitudinal section of a valve, cylinder and piston, constructed
according to my Invention.
Fig. 2, is a plan, and
T
0
Nation
taken on the line of Fic 1

page_text: A, is the valve which is circular at its ends and inverted at its centre, as shewn
in figs. 1 and 3; it is turned to fit the valve case B. To prevent the valve from
rotating whilst at work, a hole is drilled through its centre longitudinally, and
slotted through for the feather C, which is fitted into the bar D, which passes
through the valve. This bar serves the purposes of securing the covers of the
valve case and retaining the valve in its proper position when at work, and also
preventing friction and wear in the valve case. The valve case B, is provided with
exhaust ports E, E, Figs. 2 and 3, and controlling ports F, F1, for the valve. These
ports lead to cach end of the case, as shewn by the dotted lines in the plan, Fig. 2,
and are led down into the main cylinder G, by passages H, H¹. From this point
the exhaust and vacuum are carried by the recess K, in the piston L, to the
openings M, M¹, in the cylinder, through the main exhaust port N. This operation
is entirely independent of the live power at either end of the main cylinder, and
is one of the greatest features in this invention. 0,0¹ are grooves located in the
ends of the valve case, their objects are to relieve the valve from any accumulation
of water arising from the condensation of the steam, and to protect the valve from
shocks, when at work. These relief grooves are also of great importance in this
Invention. The piston L, is also an important feature in this invention, with the
recess K, in the centre, which regulates the exhaust from the valve and controls its
movement, by opening and closing the ports and passages leading from the valve
case to the main cylinder.
The working of the engine upon which the valve case, cylinder, and piston are
erected, is as follows:-When the steam, air, or other fluid, enters the valve case B,
it is admitted through one of the grooves P, P', of the valve A, into one of the
ports Q, Q, of the case B, and along one of the ports R, R¹, in the cylinder G, on
to the end of the piston L, causing the same to move forward and close one of the
exhaust ports M, M', and controlling ports H, H¹, and opening the opposite ones
for the valve to exhaust through one of the openings M, M¹, into the main
exhaust N. The valve is then driven over to the opposite end of the case, thus
admitting the live power to the opposite end of the piston, causing the return
stroke of the engine. The passages E, E, shewn in dotted lines in fig. 2, and the
tubes H, H¹, shewn in figs. 1 and 2, are passages through which the exhaust fluid
passes alternately for the movement and controlment of the valve. The ports R, R¹,
in the cylinder, and Q, Q1, in the valve case are for conducting the live power into
the main cylinder G, and the port N, is for conducting the exhaust from the main
cylinder.
The rings S, S1, S2, S3, on the piston L, are the ordinary Ramsbottom steel rings.
T, T¹, are the covers of the main cylinder, and V, the gland for stuffing box,
through which the piston rod W, passes.
Having described the operation and working of the valve and piston, according
to my Invention, I proceed to describe the means by which I effect the reversing of
double and single cylinder engines, without the aid of link motion, eccentrics, or
other gear, as hitherto required and used on locomotives, and other engines, where
reversing is needed and essential.
1. If the engine is a double cylinder engine, then, in that case, the steam, or
other power, is admitted by a three-way-cock, into the valve case for distribution
to whichever piston is then standing in the position (near the end of its stroke)
favourable for the way required to move the engine, whether forwards or back-
wards, and, as soon as the engine moves in the direction required, then the
steam, or other power, is admitted to both valve cases, and thence into the main
cylinders, by opening the three-way-cock full.
2. If the engine is a single cylinder engine, then the steam, or other power, is
admitted into the valve case by a single-way-cock, and providing the piston is
not standing on the point of stroke, favourable for the engine to travel the way
required, then only a small portion of steam, or other power, is admitted through
the valve case, into the cylinder, to slightly move the piston which, in turn, is the
means of regulating the valve to the position required for the admission of the

page_text: steam, or other power, for the movement of the piston in the direction so required
for reversing the engine in the opposite direction.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, I declare that what
I claim is
1. The construction of the valve and valve case, with ports and passages, as and
for the purposes described, and as shewn in the drawings.
2. The construction of the main cylinder, with ports, pipes and passages, as and
for the purposes described, and as shewn in the drawings.
3. The construction of the piston for the main cylinder, with recess in centre, as
and for the purposes described, and as shewn in the drawings.
4. The arrangement for controlling and actuating the slide valve, without gear,
consisting of the ports R, R¹, the passages E, E, the relief grooves O, O¹, and the
recess K, in the piston, as described and as shewn in the drawings.
5. The movement of the valve by the exhaust power, combined with the vacuum,
caused by the recess in the piston covering and uncovering the various ports in the
cylinder, during the stroke of the piston, substantially as herein described.
6. The arrangement and combination of the valve, valve case, cylinder and
piston, as herein described and shewn in the drawings, whereby the reversing the
engine is effected without link motion or other gear.
Dated this 31st day of August 1885.
ERNEST DE PASS, Fel. Inst. P.A.,
68, Fleet Street, London,
Agent for the Petitioner.