IMPROVE- MENTS IN STEAM AND OTHER ENGINES
Year: 1874

page_text: LETTERS PATENT to Joseph Higham, of Wigan, in the County of
Lancaster, Mechanical Engineer, for the Invention of "IMPROVE-
MENTS IN STEAM AND OTHER ENGINES."
Scaled the 11th December 1874, and dated the 30th July 1874.
PROVISIONAL SPECIFICATION left by the said Joseph Higham at
the Office of the Commissioners of Patents, with his Petition, on
the 30th July 1874.
I, JOSEPH HIGHAM, of Wigan, in the County of Lancaster, Mechanical
Engineer, do hereby declare the nature of the said Invention for “Im.
PROVEMENTS IN STEAM AND OTHER ENGINES," to be as follows:-
This Invention relates, first, to the slide valves of steam and other
engines and consists in improved arrangements and constructions for
enabling the valve to work throughout its stroko or travel in a perfect
cquilibrium.
In all cases tho back of the valve is planed and scraped parallel with
the face and is exactly of the same length and breadth, and the two

page_text: sides are equal in area and also tho two ends, and whatever is done to
the valve in its steam chest on any one of its sides its opposite side must
be similarly treated. As the steam is removed from the face of, the
valve by its contact with the cylinder face in which are the two steam
• ports I cause the steam to be removed from the back of the valve by
having a similar face presented to it which contains two blank steam
ports of the same length and breadth as those in the cylinder face, and
directly opposite to them; and in some cases the face presented to the
back of the valve is the inside of the cover of the steam chest, and in
other cases the face is separate and made adjustable from the outside of
the cover.
In the back of the valve are drilled a scries of holes in linc
with the exhaust lips of the face, through which holes the steam is
discharged from the blank steam ports over the back of the valve simul-
taneously with their corresponding ports of the cylinder, and meeting in
the exhaust chamber of the valve, thereby causing it to work throughout
its stroke in a perfect equilibrium; and when it is desired to overcome
the weight of the valve itself I diminish the under surface of contact
equally at the corners of the valve for the purpose of exposing a
pressure of steam underneath the valve more than at the top, in propor-
tion as its gravity is to the pressure per square inch of steam.
In those engines where the steam is used expansively the two blank
steam ports over the back of the valve are cach connected to-their cor-
responding steam ports of the cylinder by a small tube, which will vary
in size, according as the size of the ports vary in different engines. By
imcans of these two connecting tubes tho back and the face of the valvo
partake of the varying pressure of steam simultaneously with the
varying pressure in the cylinder. The steam from the blank steam
ports is also discharged by these tubes along with the discharged steam
from the cylinder; and these improvements are also applicable to the
slide valves of steam hammers.
Another part of my Invention relates to the pistons of horizontal
steam and other engines, and has for its object reducing to a minimum
the wear and tear of the bottom sides of tho piston and cylinder, and
preserving their circular shape by causing the rim of the piston to be
acted upon by a pressure of steam corresponding with the weight of the
piston and half the piston rod. The piston may be either hollow or solid,
and the steam used expansively or non-expansively, and in one arrange-
ment, when the piston is hollow, I form in the rim of the piston below

page_text: its horizontal diameter a number of holes leading into the interior, and
from each hole through which the condensed steam is discharged at cach
end of the cylinder a small half-round groove is cut along the bottom
of the cylinder, sufficiently long to communicate with a small hole in
the rim at the bottom of the piston for the admission of steam to its
inside when at each end of its stroke. As the inside of the piston
when at each end of its stroke receives the full pressure of steam by the
groove communication, the steam is cut off at the end of the groove from
the inside of the piston by its alternate motion, and whether it be driven
by the steam expansively or non-expansively, the inside of the piston
retains the full pressure throughout its stroke, and such pressure being
directed against the sides of the cylinder through the divided opened
arca in the rim of the piston and against its top inside; it is thus
borne up to a minimum throughout its stroke from the bottom of the
cylinder.
The steam areas for supposing the piston from the cylinder bottom
may be formed in the piston ring grooves, a part of each ring being
removed and a copper plug being screwed into the grooves at each end
of the rings to prevent the steam from getting beyond its area. The
steam area may be cut in the solid of the rim of the piston between the
ring grooves by a series of small square or round holes, all joined together
by channel grooves, or the area may be cut on each side of the piston
outside its rings.
The condensed steam of the pistons is discharged along with that of
the cylinder by its groove communications.
These improvements in pistons are also applicable in the same way
to similar engines that are worked by compressed air, and also by those
that are used for compressing the air into the air chamber.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirtieth day of July, in the year of
our Lord One thousand eight hundred and seventy-four, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Joseph Higham, Her special license,
that I, the said Joseph Higham, my executors, administrators, and
assigns, or such others as I, the said Joseph Higham, my executors,
administrators, and assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term
therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ircland, the
Channel Islands, and Isle of Man an Invention for " IMPROVEMENTS IN
STEAM AND OTHER ENGINES," upon the condition (amongst others) that I, the
said Joseph Higham, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should parti-
cularly describe and ascertain the nature of the said Invention, and in
what manner the same was to be performed, and cause the same to bo
filed in the Great Seal Patent Office within six calendar months next
and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Joseph Higham, do hereby declare
the nature of my said Invention, 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 Figures on the
accompanying Sheet of Drawings, and to the letters of reference
marked thereon (that is to say) :-
Que part of this Invention relates to the slide valves of steam and
other engines, and consists in improved arrangements and constructions
for enabling the valve to work throughout its stroke or travel in a perfect
equilibrium.
The length, breadth, and depth of the valve is determined by the
capacity of the steam chest for which it is intended; and in all cases
the back of the valve is level throughout, it being planed and scraped
parallel with the face, and made exactly of the same arca in length
and breadth as the face. All opposite sides of the valve, such as tho
back and the face, the two ends, and the two sides, must be equal in
arca, in length, and breadth to cach other, the principal of these improve-
ments being that whatever is done to the valve in its steam chest on any
one of its sides its opposite side must be similarly treated; for instance,

page_text: as the steam is removed from the face of the valve by its contact with
the cylinder face in which are the two steam ports, so also the steam is
removed from the back of the valve by having a similar face presented.
to it which contains two blank steam ports exactly equal in area, in
length, and breadth, in the same position as and directly opposite to the
two steam ports of the cylinder face; then as the valve in its travel.
receives a varying pressure of steam on its face in proportion as it is
alternately exposed at each of the cylinder steam ports, so also does the
back of the valvo simultaneously and in the same proportion with its
face directly opposite receive an equal varying pressure. A series of
holes are drilled through the back of the valve in a line with the exhaust
lips of the face through which the steam is discharged from the blank.
steam ports over the back of the valve simultaneously with their corre-
sponding ports of the cylinder, and meeting in the exhaust chamber of
the valve, thus causing it to work throughout its travel in a perfect
equilibrium.
When it is desirable to reduce to a minimum the friction caused by
the weight of the valve the pressuro per square inch of steam and the
weight of the valve being known multiply the pressure by the weight
and the product will be the area, to be divided into four equal parts, one.
part being placed at each of the four corners of the bottom side of tho
valve, or in other words exposing a pressure of steam underneath the
valve more than at the top, which will be equal to its weight and in
opposition to its gravity.
. On the accompanying Sheet of Drawings Fig. 1 is a cross section of a
steam chest valve and cover; Fig. 2, a plan of the inside of the cover;
and Fig. 3, a plan of the top of the valve, representing one arrangement
of my improvements; the steam chest being marked a, the cover b, and
the valve c. In this arrangement the face presented to the back of the
valve is the inside of the cover itself, in which there are recessed spaces d
forming the blank steam ports; and in the top of the valve thero are
holes e, Figs. 1 and 3, for exhausting the blank steam ports in the cover.
In Fig. 1 only one of the blank ports is seen in section, but in Fig. 2
both ports are seen, and also the limit of the facing against which the
back of the valve will travel.
Fig. 4 is a longitudinal section of a steam chest and its appendages,
in which the face ƒ containing the blank steam ports d is made adjustable
from the outside of the cover. In this Figure the valve c is travelling.

page_text: to the right, as shown by the arrow, and a portion of its face is exposed
to the pressure of the steam, and its back directly opposite is also exposed
in the same proportion, as indicated by the split arrow on the left, whilst
the arrow on the right indicates tho exhaust. The adjustablo face ƒ.
(which is ribbed on its back to strengthen it) is suspended by the
screwed spindle and nut in small engines in the centre, and adjusted
by four set screws i.
In largo engines where the area of the adjustable face is very large
the suspending power is distributed equally to the required number of
spindles, allowing to each about one hundred square inches area. Each
spindle passes through the centre of a screwed metal plug, which screws
into the steam chest cover by its six-sided head on its outside end, on
which rests the nut of the spindle.
Fig. 5 is a plan of the top side of the cover, shewing the suspending
spindle and nut h, the four adjusting screws i in position, and the blank
ports d in dotted lines; and these improvements are especially applicable
to the slido valves of steam hammers.
Fig. 6 is a sectional plan of a steam chest common to two cylinders,
as in many locomotives, and in this steam chest there are two valves c
of the samo description as before. A space of an inch or an inch and a
half between the backs of the two valves is filled by introducing a
parallel planed and scraped plate & which contains the two blank steam
ports on each side, and reaches to the end of the steam chest, and from
the bottom to the top, and is secured by four cross bars reaching to the
sides of the steam chest, which are notched in the centre to fit similar
notches in the slide, the ends of the cross bars being secured by a set
screw in each end, as will be seen by a reference to the Figure named;
and also Fig. 7 is a side view of the plate, shewing two of its blank
steam ports; the dotted lines surrounding it aro the inside of the steam
chest. The two lower cross bars in this Figure are shown in section at
the notch in the slide.
Fig. 8 is a side view of a slide valve with its two ends indented to
allow for the passage of steam from one side to the other between the
sides of the steam chest and the ends of the valve, and Fig. 9 is a plan
of the face of Fig. 8, showing the manner of placing the area at each of
its corners for the action of the steam in opposition to the gravity of the
valve, which is only necessary when the valve is a very heavy one.

page_text: The Figures 10, 11, and 12 are three different views of an adjustable
plate for the two valves of a steam chest common to two cylindors.
On each side of an inclined plane or wedge 12, the head of which is
shewn by the arrow in Figure 11, is an adjustable face containing two
blank steam ports, the top and bottom of each face being held to the
sides of the wedge by its clamped grooves, as seen in the end view
Fig. 10, the top and bottom edges of the wedge sliding in fixed grooves.
From the head of the wedge there is a screwed spindle fitting a female
spindle, which passes through the steam chest cover, by turning which
the wedge is forced along its grooves in the direction of the arrow in
Fig. 11. A fixed pillar precedes the point of the wedge in the grooves,
and a similar pillar is placed at the head of the wedge, and fastened by
set screws. As the wedge is forced onwards the projections of the pillars
cause the blank port faces to move at right angles, or cause them to
expand to the backs of the valves in the directions of the four small
arrows in Figures 10 and 12.
In those engines where the steam is used expansively the two blank
steam ports over the back of the valve are each connected to their cor-
responding steam ports of the cylinder by a small tubo which will vary
in size, according as the size of the ports vary in different engines. By
means of these two connecting tubes the back and the face of the valvo
partake of the varying pressure of steam simultaneously with the varying
pressure in the cylinder. The steam from the blank steam ports is also
discharged by these tubes along with the discharged steam from tho
cylinder.
Another part of my Invention relates to the pistons of horizontal
steam and other engines, and has for its object reducing to a minimum
the wear and tear of the bottom sides of the piston and cylinder, and
preserving their circular shape by causing the rim of the piston below
its horizontal diameter to be acted upon by a pressure of steam corres-
ponding with the weight of the piston and half the piston rod. Whilst
the piston in the cylinder is held in position by the cotter passing
through the cross head and piston rod, a perpendicular line is scribed on
each side of the piston through the centre, which is called the "gravity
line," and at right angles to it a second lino is scribed, which is called.
the "horizontal diameter." The weight of the piston and half the
piston rod, and the constant or mean pressure of steam per square inch
being known, then, by dividing the weight by the pressure, the result

page_text: will be the area in square inches to be exposed to the pressure of steam
in the rim of the piston below its horizontal diameter, one-half the arca
to be so exposed on each side of the gravity line and equidistant from
it. The piston may be either hollow or solid, and the steam may be
used expansively or non-expansively.
Where it is desirable to have these improvements applied to those
engines that have become already worn in the piston and cylinder
bottoms I expose as much steam area in the manner aforesaid as is con-
sistent with the safety of the piston.
On the accompanying Sheet of Drawings Fig. 13 is a cross section,
and Fig. 14 is a side section of a cylinder and a hollow piston. From
cach hole through which the condensed steam is discharged at each end of
the cylinder a small half round groove is cut along the cylinder bottom,
about two inches long, half inch broad, and one-eighth inch deep, or
sufficiently long enough to communicate with the small holo in the rim
at the bottom of the piston for the admission of steam to its inside when
at each end of its stroke, as indicated by the small bent arrow at the
bottom of the piston on its left in Fig. 14. As the inside of the piston
when at each end of its stroke receives the full pressure of steam by the
groove communication the steam is cut off and the end of the groove
from the inside of the piston by its alternate motion, and whether it bo
driven by the steam expansively or non-expansively, the inside of the
piston retains the full pressure throughout its stroke, and such pressure
being directed against the sides of the cylinder through the divided open
arca in the rim of the piston, and against its top inside, it is thus borne
up to a minimum throughout its stroke from the bottom of the cylinder
on pillars or columns of steam, as indicated by the steam arrow in the
cross section, Fig. 13.
The steam areas for supporting the piston from the cylinder bottom
may be exposed in various ways, some of which are shewn in the following
Figures :—
In Fig. 15 the steam area is in the piston ring grooves, a part of cach
ring being removed, and a copper plug being screwed into the grooves
at each end of the rings to prevent the steam from getting beyond its
arca. In this Figure the two grooves are joined, as indicated by the
series of little grooves cut crosswise between them, and Fig. 16 is its
sectional plan at one of the ring grooves,