IMPROVEMENTS IN DIRECT ACTING ENGINES AND PUMPS, APPLICABLE ALSO TO OTHER MOTIVE POWER ENGINES
Year: 1881

page_text: LETTERS PATENT to Christopher Thomas Wordsworth, of Leeds, in the
County of York, for an Invention of "IMPROVEMENTS IN DIRECT ACTING
ENGINES AND PUMPS, APPLICABLE ALSO TO OTHER MOTIVE POWER ENGINES."
PROVISIONAL SPECIFICATION left by the said Christopher Thomas
Wordsworth at the Office of the Commissioners of Patents on the 2nd March
1881.
CHRISTOPHER THOMAS WORDSWORTH, of Leeds, in the County of York.
"IMPROVEMENTS IN DIRECT ACTING ENGINES AND PUMPS, APPLICABLE ALSO TO
OTHER MOTIVE POWER ENGINES.".
The Invention relates to improvements in direct acting engines, either rotative
or non rotative, and actuated by steam, gas, air, or water, and consists in the first
place of improvements in the slide valves of such apparatus. The object of this
part of my Invention is to dispense with the ordinary cylindrical valves, and
substituting therefor a steam motioned valve or valves having flat or inclined
surfaces and working in a suitable chamber or chambers, and controlled and
operated upon by a mechanically moved valve or valves through a combination of
levers or other suitable mechanism. The valve or valves are so arranged and
formed with suitable passages and ports so as to allow of the ingress and egress of
steam, air, gas, or water required to impart motion to a moveable piston working in
the main cylinder of such engines or pumps. The Invention relates in the second
place to arrangeing the mechanical motion valve or valves with suitable ports and
passages in order to cut off the steam on the steam side, or to cut-off the
eduction or exhaust on the other side, if required, at any part of the in or
out stroke of the piston, thereby having an expansive action on the steam
side, and on the exhaust side having a positive cut-off and cushioning action
on the piston at each end of the stroke. This valve may be used separately or
in combination with other valves, and without the eduction cut-off passage
and ports if required. The Invention relates in the third place to improve-
ments. in this class of engines is, in the application of an automatic governor
arrangement to prevent the engine racing by cutting off to the aforementioned
D

page_text: mechanically moved valve or other suitable means. The said automatic governor
consists of a small cylinder suitably placed and moveable on or in suitable rods,
guides, or projections, and by preference rods moving parallel to the main cylinder
secured in brackets. The cylinder has a small piston, either perforated or of a
reduced diameter to the bore of the cylinder, and working in a liquid, by preference
water, in the form of a catheract or splash pot, the said piston being actuated by
the motion of the main engine through suitable mechanism. The cylinder, having
either one uniform bore or a number of annular chambers, is acted upon by the
motion of the piston working in the liquid through friction, the said cylinder being
moveable and so adjusted by springs, weights, or levers in order to increase or
decrease the amount of friction as required for a suitable motion for the main
engine. The same cylinder when acted upon as described is suitably connected by
levers or other mechanism, is made to operate or actuate the cut-off valve or by the
means as herein before described.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by..
the said Christopher Thomas Wordsworth in the Great Seal Patent Office on
the 2nd September 1881.
CHRISTOPHER THOMAS WORDSWORTH, of Leeds, in the County of York.
"IMPROVEMENTS IN DIRECT ACTING ENGINES AND PUMPS, APPLICABLE ALSO TO
OTHER MOTIVE POWER ENGINES."
My Invention relates to direct acting engines and pumps, either rotative or
non-rotative, actuated by steam, gas, air, or other fluids, and consists of improve-
ments in the manner of actuating the slide valves of such apparatus, and has for
its object in the first place to dispense with the ordinary cylindrical valves, and
substitute therefor a valve or valves having either flat or inclined surfaces, such
valve or valves working in a chamber or chambers actuated by steam, gas, or other
fluids admitted through suitable ports or passages opened by a mechanically moved
valve. This mechanically moved valve, hereafter referred to as the main valve or
valves, and on account of the distinctive motion, I shall refer to the same as
"shuttle valves," and for the sake of conciseness I will describe the pump
or engine throughout this Specification as actuated by steam, and refer to
the shuttle valve in the singular, although there may be more than one...
The function of the shuttle valve is to admit steam through suitable ports and
passages to the cylinder, in which works the main piston of the engine. The main
valve is provided with ports and passages, in order to cut-off the eduction or
exhaust steam on the exhaust side of the main piston at any required part of the
stroke, by which means a cushioning action on the exhaust side of the said main
piston is obtained, and it is rendered impossible for the said piston to strike the
cylinder covers. The main valve may be used separate from or combined with
other valves, and may be constructed without the cut off ports or passages if
required. My Invention relates in the second place to the employment in engines
of this class of an automatic governing arrangement, having for its object to prevent
the engine "racing." I obtain this result by cutting off the steam from the main
piston either by a plate or valve on the back of the main valve, or by a suitable
cut off valve fixed as close to the said main valve as possible, such plate or cut off
valve being actuated in the following manner:-I use a comparatively small
cylinder suitably mounted and arranged to be moveable in or on rods, guides, or
projections, and by preference rods fixed parallel to the axis of the main cylinder,
the said small cylinder being provided with a piston which may be either perforated
or made of smaller diameter than the bore of the cylinder, and working in a liquid.
in the manner of a cataract or dash pot. The small piston is actuated by and
derives its motion from the main piston rod by suitable connexions, the said small
cylinder being actuated by the motion of its perforated or small piston producing
friction in the liquid contained in the said cylinder, or the piston may fit the
cylinder, and friction be obtained by restricting the passage of the liquid from.one
end of such cylinder to the other by means of a tap or other suitable arrangement
outside. The above described small cylinder or dash pot being mounted on guides
is restrained in its motion by springs, levers, or weights so adjusted as to offer any
desired resistance to its motion in proportion to the resistance caused by the friction
of the fluid passing the small piston, so that if the speed at which the springs,

page_text: levers, or weights are adjusted is increased, the friction of the fluid causes the small
cylinder to overcome the resistance of the said springs, levers, or weights, and the
resulting motion of the said small cylinder is utilised to cut off the steam from the
main piston.
In order to render my Invention more explicit, I have caused to be appended
hereto a Sheet of Drawings of the various arrangements which I now proceed to
describe, similar letters of reference indicating like parts. Figs. 1 to 9 illustrate
one method of carrying out my Invention, and one in which I use the main valvo
to cut off the exhaust of the main piston before the end of its stroke, so as to
obtain a positive cushioning action on the said main piston, and prevent it from
striking the cylinder covers at the end of each stroke. Figs. 1 to 7 refer to one
and the same arrangement of cylinder and valves. Figs. 8 and 9 represents a
modification of the valves, having for its object the reduction of space occupied, and
also reduction of load on the valves. In Fig. 7 is represented one method I use to
actuate the main valve of the steam cylinder. On the piston rod A is fastened a
crosshead lever B, coupled as shown to links c, c, c, by which means a positive
motion is given to the main valve spindle D, in same direction as the motion of the
main piston. I wish it however to be understood that I do not confine myself to
this method of moving the main valve, as any well known and suitable mechanical
arrangement may be used for this purpose. Figs. 1 to 6 represent the steam cylinder
and valves of a direct acting pump arranged according to my Invention. In Figs. 1
to 3 a steam cylinder is shown fitted with a piston, and having a cavity C, into which
are led the steam ports F, F, and in which cavity also works the "shuttle" valve A.
The upper face of this "shuttle" valve is made in the same plane as the main
valve face of the cylinder, and on this face rides the main valve B which works
steam tight against the upper face of the shuttle valve. The "shuttle" valve A
is formed with flat faces inclined at the sides, as shown in Fig. 3, in order to remain
tight after long wear. Through this valve ports D, D¹, are formed for the admission
of steam to one or other of the main steam ports F, F', of the main cylinder. In
the centre of this valve another port E is formed, which forms the exhaust
connexion between one or other of the ports F, F¹, and the main valve B above it.
The "shuttle" valve A is formed with two bars G, G¹, which when the valve is in
mid position exactly cover the main ports F, F'; it will be evident therefore that
any motion in either direction of the "shuttle" valve admits steam to one or other of
the two ports F, F¹, and exhausts the other port through its own cavity or port E
aud through a port H in the main valve (see Fig. 6). This port in the main valve
is always in connexion with the port E in the "shuttle" valve, but before the steam
in these ports can escape into the atmosphere it has to pass another port or
ports I, I', in the main valve face of the cylinder. These ports I, I, in the valve
and in the face are of such a width that when the main piston has travelled a
certain desired part of its stroke the exhaust is cut off by reason of the closing of
the ports I, I, due to the further motion of the main valve, and the motion of the
main piston is therefore arrested by a steam cushion. The ports D, D¹, in the
shuttle" valve A are always in communication with the ports J, J', cut through
the main valve into the steam space. Having now described the construction of
the main and shuttle valves, I will now explain their action in relation one to the
other. Supposing the shuttle valve A to be in such a position that the main piston
is proceeding in the direction shown by the arrow in Fig. 1, that is, the shuttle
valve would be thrown over to the right and steam would be passing through
port J in main valve and through ports D and F in shuttle and main cylinder
respectively. The exhaust would be passing along F, through E in shuttle valve
and ports H and I, I', in main valve, and away to the atmosphere through exhaust
pipe K. Toward the end of the stroke of the main piston, still moving in the
direction of the arrow, the ports I, I, in main valve and main valve face close
(as shewn in Fig. 4), and the main piston is therefore cushioned down; at this

page_text: instant of time a small hole L' in the main valve comes opposite a notch m¹ (Fig. 2)
leading into the cavity C, and steam is admitted through this to one end of the
cavity C. at the same time the other end of this cavity is placed in connexion
with the exhaust by means of the passage N leading into the slot O, which is
always in communication with the outer exhaust through the hole P (see Fig. 2).
The consequence is that the shuttle valve A is blown over to the other end of
cavity C, as shown in Fig. 4. The distribution of steam to the main piston is now
changed and the piston tends to make a return stroke, the exhaust is still
cut off and the imprisoned exhaust steam is acting against the live steam on the
other side of the piston. In order to facilitate the commencement of the return
stroke and releive the exhaust side of the piston I put a notch Q in the side of the
shuttle valve communicating with the cavity E; this notch as soon as the valve
is thrown over, as shown in Fig. 4, comes into gear with a link-passage R in the
main valve leading into the slot O. and to the atmosphere (see Fig. 6). Sufficient
exhaust steam escapes by this means to enable the piston to make a move and open
the main exhaust ports I, I¹. When the shuttle valve is blown to the other end
of the cavity C the link R¹ comes into gear with the notch Q precisely in the same
manner. The position of the passages N, N', when the shuttle valve is thrown
over is such that the end of the cavity C is exhausted up to a small distance from
the end of the travel of the shuttle valve, beyond which point the exhaust is cut
off and the valve is prevented from hitting the end of the cavity, and is thus
cushioned down and rendered noiseless. Figs. 8 and 9 indicate a modification of
the main and shuttle valve designed to reduce load and economise space. Fig. 8 is
the shuttle valve; in the upper face are the ports E for exhaust steam and ports
D, D¹, as before, but these have now been twisted round a quarter turn so as to lay
in the direction of travel of the valve; the lower face remains the same with the
exception that the ports can now be brought closer together, as shown by the dotted
lines, a corresponding alteration being made in the cylinder ports. The main
valve, Fig. 9, has exactly functions as before, but it is shortened and the ports
H, J, J', are altered to suit the new conditions in the shuttle valve. In this
main valve only one port I is shown; the exhaust H is shown on both Figs. 8 and 9
between two steam ports, but it may be equally well arranged with one steam port
between the exhaust ports on the upper [face of shuttle valve, the lower face
remaining the same. Figs. 10 to 13 indicate another method by which my
Invention can be carried out. In this case I use a main valve without the eduction
cut off edges or ports. The steam passages come in at the side of the shuttle valve,
the exhaust being carried through the port E as before into the cavity H, which is
always in communication with the outer exhaust K, therefore in this case the link
slots R, R¹, used in the former case are not necessary. The letters in Figs. 10 to
13 refer to parts which have exactly similar functions to those of corresponding
letters in the other Figures. If desirable I can use the type of shuttle valve in
Figs. 10 to 13, and still have a positive exhaust cut off by the main valve by a
suitable disposition of ports in the manner herein before described. I would have
it to be understood that I do not confine myself to the exact arrangement of ports
and shape of valves described and illustrated in the Drawings, as the same may be
varied without departing from the nature of my Invention.
Having now described and indicated the nature of my Invention, and
means for carrying the same into effect I would have it to be understood that
I claim,―
First. The method of admitting steam to a cylinder by means of the combination
of a mechanically moved slide valve and a separate "shuttle" valve working in a
cavity with flat or inclined faces in the cylinder, substantially as herein set forth
and illustrated in the Drawings.
Secondly. The arrangement of ports and passages in the main and shuttle valves,
substantially as described and illustrated in the Drawings.

page_text: And Lastly. The general arrangement and combination of parts for the purpose
specified.
In witness whereof, I, the said Christopher Thomas Wordsworth, have
hereunto set my hand and seal, this First day of September, in the year
of our Lord One thousand eight hundred and eighty one.
CHRISTOPHER THOMAS WORDSWORTH. (L.S.)
Signed and sealed by
the said Christopher
Thomas Wordsworth,
in the presence of
HUGH G. GRANT, M.E.M.S.A.,
Patent Solicitor,
Of the Firm of Bosshardt & Grant,
24, Bull's Head Chambers,
Manchester.