IMPROVEMENTS IN STEAM ENGINES
Year: 1878

page_text: LETTERS PATENT to James Howden, of Glasgow, in the County of Lanark,
North Britain, Engineer, for the Invention of "IMPROVEMENTS IN STEAM
ENGINES"
Sealed the 24th September 1878, and dated the 30th March 1878.
PROVISIONAL SPECIFICATION left by the said James Howden at the
Office of the Commissioners of Patents on the 30th March 1878.
JAMES HOWDEN, of Glasgow, in the County of Lanark, North Britain, Engineer.
"IMPROVEMENTS IN STEAM ENGINES."
This Invention of improvements in steam engines has generally for its objects to
utilise in au improved manner a portion of the heat ordinarily communicated to
the condensing water; also to diminish the concussive action and consequent wear
and tear of heavy moving parts; and also to diminish the power required for working
the cylinder valves.
The first part of the Invention is chiefly designed for application to compound
surface-condensing steam engines, but it may also be applied to other kinds, and in
carrying it out two condensers are employed, one herein-after termed the main
condenser, and which is by preference somewhat smaller than an ordinary surface
condenser relatively to the size of the engines, and the other herein-after termed the
supplementary condenser, and which is of a small size, and is arranged as a jet
condenser.
The water injected into the supplementary condenser is the water of condensation
from the main condenser, and which is withdrawn therefrom in the ordinary way
by an air pump. Steam is admitted to the supplementary condenser from the low-
pressure cylinder by a special valve or pair of valves, worked by preference from
small tappets on the crank shaft, and arranged, according to one modification, to
open a communication between the cylinder and the supplementary condenser at
about the middle of each steam stroke, such communication being closed at about
the time the main exhaust opens; or the said communication may be opened
earlier or later in the stroke; or the steam for the supplementary condenser may
be taken from the low-pressure valve casing.

page_text: The water injected into the supplementary condenser, combined to that due to
condensation therein, is of increased heat, and being withdrawn by an air pump
or otherwise, and fed into the boiler in the ordinary way, serves thereby to
economise fuel, whilst a diminished quantity of steam has in consequence to be
condensed in the main condenser, and less heat is thrown away therein.
The supplementary condenser is by a further improvement enveloped by a jacket
or casing, into which the comparatively cool water from the main condenser is led
prior to entering the supplementary condenser itself, and this prevents loss of heat
by radiation and undue heating of the engine room. In like manner the pipe con-
veying the steam to the supplementary condenser may be enveloped in a casing,
through which the water is passed either before or after it has been in the supple-
mentary condenser.
In compound engines in which more than two cylinders work in successive con-
nection, the steam for the supplementary condenser may be taken from the valve
casing between the last and preceding cylinder.
Instead of the supplementary condenser being a jet condenser it may be a surface
one, either with the water inside tubes or with the steain inside tubes and the
water dripping externally over the tubes.
In some cases the supplementary condenser may be placed in a position admitting
of the feed water being drained from it by the feed pump, and so as to require no
separate air pump.
The second part of the Invention consists, according to one modification, in em-
ploying one or more air cylinders to counteract injurious strains and concussive
tendencies due to the vertical or up-and-down movements of heavy parts of steam
engines. In the case, for example, of inverted cylinder screw propeller engines, the
pistons, piston rods, connecting rods, and cranks which are heavy and move rapidly up
and down, being unbalanced in ordinary engines, cause through the reciprocation
of their weight, great wear and tear of all the connections and heating of the
bearings. To correct this the air cylinder is, according to one modification, placed
above the steam cylinder, the piston rod of the latter being extended through
stuffing boxes to the piston of the former.
The air cylinder is made of a suitable size, or is in communication with a
reservoir, or chamber, or accumulator, and the air under the piston is by preference
of such a pressure as that when the steam piston is at the top of its stroke the
weights of the moving parts will not be wholly balanced by the air, and so that
when the steam piston is at the bottom of its stroke the air being then in a
more compressed state will have a pressure equivalent to rather more than the
weight of the moving parts. This arrangement will prevent concussion of the joints
and bearings at the commencements of the down and up strokes respectively, and
will so reduce the injurious tendencies of the moving weights as to admit of the
engines running at high speeds with smoothness and safety.
The air cylinder (which may be made comparatively small if air of considerable
pressure is employed), or two or more such cylinders may be placed below the
steam cylinder, and even in some cases below the crank shaft, and the air piston or
pistons may be connected in any convenient way to the moving parts.
In the case of engines with horizontal or inclined cylinders the air cylinder or
cylinders is or are by preference still applied vertically by means of a separate rod
or rods connecting them to the crank.
The air balancing cylinders may also be advantageously applied to the valves and
their gear.
When any of the air cylinders arranged so that the compressed air is on the side
of the piston opposite to that of the rod, stuffing boxes can be dispensed with. Any
leakage of air from an air cylinder or chamber in connection therewith can be made
up by means of a small self-acting pump worked from any convenient moving part
of the engines.
In some cases steam may be used in the balancing cylinder or cylinders.
The third part of the Invention relates to the cylinders valves, and is more

page_text: particularly applicable to vertical cylinders. In carrying it out in the case of a
single cylinder or of the high-pressure cylinder of a compound engine, a separate
pair of valves is provided for each end of the cylinders, such valves consisting of
light gratings moved transversely over horizontal or vertical grating ports.
In one modification each inlet valve is above its fellow outlet valve, the space
between them communicating with the cylinder by as short a passage as possible.
In the case of a pair of compounded cylinders the valves of the high-pressure
cylinder are by preference placed at the side of it, facing the low-pressure cylinder,
and the steam from the high-pressure exhaust valves is led through one or more
spaces of sufficient size to grating valves admitting to the low-pressure cylinder
These valves are by preference fitted to work between two grated faces, and when
open allow the steam to pass directly across into the cylinder. Similar grating
valves working between two grated faces aro provided for the exhaust from the
low-pressure cylinder.
In some cases the inlet valves of the high-pressure cylinder may be placed on the
outer side, the exhaust valves only being placed on the side facing the low-pressure
cylinder.
The several valves are worked by one or more oscillating plates or combinations
of levers deriving motion from one or more eccentrics on the crank shaft or on a
counter shaft, and the points of connection with the plate or plates or the positions
of the levers aro selected so as to cause the valves to open and close quickly and to
pause or move very slowly when fully open or shut. These arrangements admit
of continuous smooth motions and of the ordinary link motion or other convenient
reversing gear.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said James Howden in the Great Seal Patent Office on the 28th September
1878.
JAMES HOWDEN, of Glasgow, in the County of Lanark, North Britain, Engineer.
"IMPROVEMENTS IN STEAM ENGINES."
My said Invention of improvements in steam engines has generally for its objects
to utilise in an improved manner a portion of the heat ordinarily communicated to
the condensing water; also to diminish the concussive action, and consequent wear
and tear of heavy moving parts; and also to diminish the power required for
working the cylinder valves.
The first part of my Invention is chiefly designed for application to compound
surface-condensing steam engines, but it may also be applied to other kinds; and
in carrying it out two condensers are employed, one herein-after termed the main
condenser, and which is, by preference, somewhat smaller than an ordinary surface
condenser relatively to the size of the engines, and the other, herein-after termed
the supplementary condenser, and which is of a small size, and is arranged as a
jet condenser.
The water injected into the supplementary condenser is the water of conden-
sation from the main condenser; and the steam condensed in the supplementary
condenser is admitted thereinto by a special valve or valves from the low-pressure
cylinder, or from the low-pressure valve casing.
The water injected into the supplementary condenser, combined with that due
to condensation therein, is of increased heat, and, being fed into the boiler in the
ordinary way, serves, in consequence of such increased heat, to economise fuel;
whilst a diminished quantity of steam has in consequence to be condensed in the
main condenser, and less heat is thrown away therein.
In compound engines, in which more than two cylinders work in successive con-
nection, the steam for the supplementary condenser may be taken from the valve
casing between the last and preceding cylinder.
Instead of the supplementary condenser being a jet condenser it may be a surface
one, either with the water inside tubes or with the steam inside tubes, and the
water dripping externally over the tubes.
The second part of my Invention consists in counteracting injurious strains and
concussive tendencies of the vertical or up-and-down movements of heavy parts of
steam engines by means of air cylinders applied in a manner herein-after
explained.
In some cases steam may be used in the balancing cylinders.
The third part of my Invention comprises certain improved constructions or
arrangements of the cylinder valves, and their actuating gear, which will be
most readily understood from the particular description of them herein-after
contained.
And in order that my said Invention, and the manner of performing the same,
may be properly understood, I hereunto append three Sheets of explanatory
Drawings, to be herein-after referred to, and representing examples of my improved
arrangements.
In these Drawings the same reference numerals are used to mark the same or
like parts wherever they are repeated.
On Sheet 1 of the accompanying Drawings there is shown the application of the
first part of my Invention to a pair of compound inverted cylinder steam engines, such
as are used for driving the screw propeller, Figure 1 being a sectional side elevation ;
Figure 2, an elevation of the side opposite to that shown in Figure 1; Figure 3, a
plan; and Figures 4, 5, 6, enlarged views of parts. In the modification shown in
these Figures (1 to 6) the water due to condensation of steam in the main con-
denser 1, after passing through the main air pump 2 in the usual way to the hot

page_text: well 3, is led by a pipe 4 to a small supplementary condenser 5, which is shown in
vertical and horizontal section in Figures 5 and 6. This supplementary condenser 5
is shown as having round it a jacket space 6; and it is into this space that the
water is first led, its presence therein avoiding same loss of heat by radiation
froin the condenser; this jacket space 6 is not, however, essential. The water enters
the condenser 5 through perforations in a pipe 7 at the top thereof, or it might be
through an ordinary rose, the steam for heating the water also entering by the
pipe 7, which communicates with two small valve boxes 8, 9, upon the low-pressure
cylindor 10. The valve boxes 8, 9, communicate with the top and bottom passages
of the cylinder, or directly with the upper and lower ends of the interior of the
cylinder; and they have in them valves for opening and closing the communications
at the proper times, these valves being worked by horizontal rods 12, 13, acted on
by levers on vertical shafts 14, 15. At their lower ends the vertical shafts 14, 15,
have fast on them levers connected by links 16, 17, to bell-cranks 18, 19, centred on a
stud 20, and situated one above and the other below the crank shaft 2 (as
shown in Figure 4). On the crank shaft 21 there is fixed a cam 22 having a cir-
cumferential groove to act on antifriction rollers on the bell cranks 18, 19 such
groove being shaped to open and close the valves at the desired times.
The cam 22 is, by preference, arranged to open the valves in the boxes 8, 9, at
about the middles of the strokes of the respective ends of the cylinder, the com-
munication being in each case closed at about the time when the main exhaust
opens. The valves may, however, be opened earlier or later in the stroke if found
to give better results. The water injected into the supplementary condenser 5,
combined with that due to condensation therein of the steam entering by the pipe 7,
is of an increased heat; and it is withdrawn from the supplementary condenser by
means of a small air pump 23, which delivers it into a hot well 24, whence it is
drawn by a pipe 25, and passed by an ordinary feed pump into the boiler.
The supplementary air pump 23 may be conveniently worked by a lever 26 on
a prolongation 27 of the rocking shaft of the levers for working the main air
pump 2.
In some cases the supplementary condenser 5 may be placed in a position
admitting of the feed water being drained from it by the feed pump, and so as to
require no separate air pump (23).
Figures 7 and 8, on Sheet 2 of the accompanying Drawings, are vertical and
horizontal sections, showing two modes of applying the second part of my Invention
to inverted cylinder marine engines; Figure 0 is a vertical section as at right
angles to Figure 7, but showing different construction of part of the apparatus; and
Figure 10 is an enlarged section of a vessel for containing compressed air used in
carrying out the improvements.
In inverted cylinder marine engines as commonly made the pistons 31, 32,
piston rods 33, connecting rods 34, and cranks 35, which are heavy and move
rapidly up and down, being unbalanced, cause, through the reciprocation of their
weight, great wear and tear of all the connections and heating of the bearings. To
correct this, I, according to one modification, place an air cylinder 36 above the
steam cylinder 37, the piston 31 or 32 of the latter being extended through stuffing
boxes to the piston 38 of the former. The air cylinder 36 is made of a suitable
size, or is in communication with a chamber or enlargement 39, formed at its lower
end, as shown in Figure 7, or with an annular casing 40 encircling it, as shown in
Figure 9, or with a separate vessel 54 in open communication with it, and in
addition, has in communication with it by a pipe 41 a reservoir or accumulator 42,
from which any loss by leakage can be made up on opening a stop-cock on the pipe
41. The air under the piston 38 is, by preference, of such a pressure as that when
the steam piston 31 or 32 is at the top of its stroke the weights of the moving parts
will not be wholly balanced by the air, and so that when the steam piston 31 or 32
is at the bottom of its stroke the air being then in a more compressed state will have
a pressure equivalent to rather more than the weight of the moving parts. This
arrangement will prevent concussion of the joints and bearings at the commence-

page_text: ments of the down and up strokes respectively, and will so reduce the injurious
tendencies of the moving weights as to admit of the engines running at high speeds
with smoothness and safety.
The air cylinder 36 (which may be made comparatively small if air of considerable
pressure is employed) or two or more such cylinders may be placed below the steam
cylinder 37, and even in some cases below the crank shaft, and the air piston or
pistons 38 may be connected in any convenient way to the moving parts.
When applying my balancing apparatus below the steam cylinder 37, it is con-
venient to use in each case two air cylinders 43 (as shown in Figures 7, 8, 9), these
cylinders 43 being placed over the crank shaft bearings, and being supported on
legs or otherwise so as not to interfere with the access to those bearings. The rods
of the air pistons 44 are attached directly to the main cross head 45, and the
cylinders 43 do not require stuffing boxes.
Any leakage of air from an air cylinder 36 or 43, or chamber 54, or vessel 42, 421,
in connection therewith, is made up by means of a small self-acting pump 46, which
may be worked from any convenient moving part of the engines. In Figure 9
the pump is represented as worked from one of the main air pump levers 47, and
it supplies the reservoirs 42, 421, by pipes 48, 49. The reservoir 42, shown
enlarged in Figure 10, is fitted with an automatic arrangement for stopping the
supply of air whenever the proper pressure is attained. The air inside the
reservoir acts on a piston or plunger 50, pressed inwards by a spring which is
of a strength, or is adjusted to correspond to the pressure required. The piston
50 is connected to a lever 51, which is connected by a rod 52 to the lever of a
stop-cock 53, on the supply pipe 48, and on the proper pressure being reached
this stop-cock is turned so as to close the entrance to the reservoir 42, and open
the pipe 48 to the atmosphere. The chamber 54 or reservoirs 42 may in many
cases be formed or cast in the bed plate or other part of the engine framing.
In the case of engines with horizontal or inclined cylinders the air cylinder
or cylinders is or are by preference still applied vertically by means of a
separate rod or rods connecting them to the crank.
My air balancing cylinders may also be advantageously applied to the valves and
their gear.
Examples of improved valve apparatus made according to the third part of my
Invention are shown upon Sheet 3 of the accompanying Drawings. This valve
apparatus is more particularly applicable to vertical cylinders, and in carrying it
out according to one modification in the case of a single cylinder, or in the case
of the high-pressure cylinder of a compound engine, a separate pair of valves is pro-
vided for each end of the cylinder, such valves consisting of light gratings moved
transversely over horizontal or vertical grating ports.
In the case of a pair of compounded cylinders the valves of the high-pressure
cylinder are by preference placed at the side of it, facing the low-pressure cylinder,
and the steam from the high-pressure exhaust valves is let through one or more spaces
of sufficiont size to grating valves admitting to the low-pressure cylinder. These valves
are by preference fitted to work between two grated faces, and when open allow
the steam to pass directly across into the cylinder. Similar grating valves working
between two grated faces are provided for the exhaust from the low-pressure
cylinder. In some cases the inlet valves of the high-pressure cylinder may be
placed on the outer side, the exhaust valves only being placed on the side facing the
low-pressure cylinder.
Figure 11 is a transverse vertical section showing valves .of the kind and
arrangement herein-before described as for a single cylinder or the high-pressure
cylinder of a compound pair.
Figure 12 is a side elevation of the valve gearing.
Figure 13 is a longitudinal vertical section showing the valves of both cylinders;
and Figure 14 is a horizontal section corresponding to the lower part of Figure 13.
The admission valves 60, 61, for the high-pressure cylinder 62 are narrow plates
formed with grate openings, and rest and work upon port faces formed with similar

page_text: grate openings, and the steam has access to the upper sides of these valves from the
jacket space 63, which surrounds the cylinder 62.
The top and bottom cylinder passages 64, 65, which are made as short as conve-
niently possible, communicate with spaces which are in both cases beneath the port
faces of the admission valves 60, 61, and in these spaces the exhaust valves 66, 67,
which are similar but rather wider plates, made with grate openings, rest and work
upon port faces formed with grate openings. These exhaust ports communicate with
the exhaust pipe or passage in the case of non-compound engines; and in compound
engines they communicate with spaces or passages 68, 69, communicating with the
adimission valves 70, 71, of the low-pressure cylinder 72.
The valves 70, 71, are "narrow plates having grate spaces formed horizontally
through them, and they work between vertical grated faces, and when open allow
the steam to pass directly across into the passages 73, 74, of the low-pressure
cylinder 72. Similar grating valves 75, 76, each working between two vertical
grated faces, control the passage of the exhaust steam from the cylinder passages 73,
74, into the main exhaust passages 77. All the valves 60, 61, 66, 67, 70, 71, 75, 76,
are moved horizontally and transversely by rods 78, passing out through stuffing
boxes at one side of the engines, and are additionally guided by rods 79, passing out
through stuffing boxes at the other side.
The valve rods 78 are worked by bell cranks 80, carried by brackets 81, and con-
nected by rods 82 to pins 83, fixed on discs 84, which are mounted loosely on a
fixed horizontal shaft 85. The discs 84 have oscillating movements, and are repre-
sented as connected by rods 86 to discs 87, carried on studs fixed in brackets 88
above the crank shaft 21, and the last-nained disc 87 are represented as worked by
means of eccentrics 89, and link motion gear. The requisite oscillating movements
may, however, be imparted to the discs 84, which are directly connected to the
The rods 82
valve levers 80 by any suitable gear connected with the crank shaft.
are shown as so connected, that each pin 83 on the discs 84 acts on the admission
valve at one end of the cylinder and the exhaust valve at the other end; but if pre-
ferred every valve may be worked by a separate pin 83, and any of such pins 83
may be adjustable on the discs 84. The positions of the pins 83 on the discs 84 are
selected so as to cause the valves to move with comparative quickness when
opening and closing, and to pause or move slowly when fully open or shut, according
to a well understood principle. Instead, however, of connecting the rods 82 to the
bell-crank valve levers 80, as shown in Figure 11, I sometimes prefer to arrange
such connection as shown on an enlarged scale in Figure 15.
In this modification one arm 90 of the bell crank is slotted, and has fitted to
work in the slot a small block 91, through which there passes a pin jointed to the
forked end of the rod 82, and also to a forked or double lever 92, capable of turning
on a fixed but adjustable centre 93. This lever 92, by making the block 91 move
along the slot of the bell-crank arm 90, makes the motion of the valve still quicker
comparatively when opening and closing, and also diminishes the motion of the
valve whilst closed so as to adinit of the valve being made with a reduced amount
of cover. The centre 93 of the lever 02 may be adjusted either horizontally or
angularly so as to vary the action of the lever, and by such adjustment the duration
of the admission of steam may be varied to some extent, the shifting of the centre
03 away from the bell crank 80, 90, increasing the duration of the admission, and
vice versa.
Figures 16 and 17 are sections as at right angles to each other, showing a modi-
fication in which rocking spindles 04 arc employed for working the valves 95, 96.
These valves 95, 96, are narrow grating valves like those (70, 75, &c.), herein-before
described, but the grate spaces in them and in the faces on which they work are
arranged the long way of the valves, and the valves are arranged to open and close
by moving at right angles to their length. The rocking spindles 94 are each fitted
with two or more short tooth-like levers 97, which engage between tooth-like pro-
jections formed on the valves 95, 96, and impart the required motions to the valves
by rocking, being themselves worked by means of levers 98 fixed on their ends, and

page_text: having the rods 82 directly connected to them, so that with this simplified arrange-
inent the bell cranks (80) are not required.
Having thus particularly described my said Invention, and the manner of per-
forming the same, I have to state that I do not restrict inyself to the precise details
herein described or delineated, but that what I believe to be novel and original,
and claim as the Invention secured to me by and in terms of the herein-before
in part recited Letters Patent is,
-
1. The combination with the parts of surface-condensing steam engines of a
supplementary condenser, arranged and worked substantially as and for the purposes
herein-before described.
2. The arrangement of valves and their actuating gear for controlling the admis-
sion of steam to the supplementary condenser, as herein-before described.
3. The connecting of heavy vertically moving parts of steam engines to the
pistons of cylinders containing compressed air, for the purpose of counteracting
injurious strains and concussive tendencies, the parts being arranged and worked
substantially as herein-before described.
4. The combination and arrangement of valves, and their ports, passages,. and
actuating gear, substantially as herein-before described with reference to Figures 11
to 14, on Sheet 3 of the accompanying Drawings, and with reference to cylinders
of non-compound engines or to the high-pressure cylinders of compound engines.
5. The combination and arrangement of valves and their ports, passages, and
actuating gear, substantially as herein-before described with reference to Figures 11
to 14 on Sheet 3 of the accompanying Drawings, and with reference to the low-
pressure cylinders of compound engines.
6. The combination of levers for working cylinder valves herein-before described
with reference to Figure 15 on Sheet 3 of the accompanying Drawings.
7. The modification of cylinder valves and their immediato actuating parts
herein-before described with reference to Figures 16 and 17 on Sheet 3 of the
accompanying Drawings.
In witness whereof, I, the said James Howden, have hereunto sot my hand
and seal, this Twenty-seventh day of September, in the year of our Lord
One thousand eight hundred and seventy-eight.
Witness.
EDMUND HUNT,
Patent Agent,
Glasgow.
JAMES HOWDEN. (L.S.)