IMPROVEMENTS IN THE SLIDE VALVES AND REVERSING GEAR OF ENGINES WORKED BY STEAM,
Year: 1866

page_text: LETTERS PATENT to William Bond, of Denmark Street, Soho, in the
County of Middlesex, Engineer, for the Invention of "IMPROVEMENTS IN
THE SLIDE VALVES AND REVERSING GEAR OF ENGINES WORKED BY STEAM, AIR,
Sealed the 12th October. 1866, and dated the 12th April 1866.
PROVISIONAL SPECIFICATION left by the said William Bond at the
Office of the Commissioners of Patents, with his Petition, on the 12th
April 1866.
.I, WILLIAM BOND, of Denmark Street, Soho, in the County of Middlesex,
Engineer, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN THE SLIDE VALVES AND REVERSING GEAR OF ENGINES WORKED BY STEAM,
AIR, OR GASES," to be as follows:-
My improvements relate, first, to the mode of arranging the parts of slide
valves of steam or other motive-power engines in order to counteract the
back pressure upon the slide valves of such engines. For this purpose the
slide which opens and closes the "ports" or steam passages to and from the

page_text: cylinder is faced up at the front and back and at each side so as to slide
steam-tight between the face of the ports and the faced up end of a short
hollow piston arranged in a cylinder forming part of the steam chest at the
back of the slide, and through or to which the steam, air, or gas (as the case
may be) is admitted to the eduction port. The slide is of rectangular shape,
and is formed with an opening or openings (between the surfaces which elose
and open the ports) for the passage of the steam to the eduction port,
the exhaust steam passing away alternately at the outer ends of the slide
into the steam chest to the exhaust pipe or passage. The hollow piston at
the back of the slide is furnished with packing so as to slide in its cylinder
by the pressure of the steam up to the faced up surface at the back of the
slide, the pressure of the steam on the opposite side counteracting any undue
pressure upon the slide, and adjustable stops are arranged to act upon the
piston to prevent its moving out of position with the slide. The passages
through the slide are so arranged that the exhaust passages when open for
the escape of steam are of larger area than they are when admitting steam to
the cylinder, the eduction passage at this time being partially covered by the
central part of the slide. By this arrangement the steam is admitted through
the false top or cover so as to act on both sides thereof, thus relieving the
slide from undue pressure, the steam being admitted through the eduction
ports or passages in the body of the slide or through the slide cover, the
exhaust steam escaping through ordinary exhaust ports alternately placed in
communication with the eduction ports by the to-and-fro movement of the
slide.
1.
The second part of my Invention relates to a mode of arranging reversing
gear or apparatus for reversing the movement of engines worked by steam,
air, or gases. For this purpose I arrange a long transverse slide furnished
with suitable ports or passages for directing the steam to either side of the
piston as required, such slide being moved (by suitable mechanism; through
stuffing boxes as is well understood) to and fro across the slide valve jacket
and steam ports to open or close the induction and eduction passages in order
to reverse the movement of the engine when required. The two induction"
ports to the cylinder are divided by a partition in the centre of each, thus
making four induction ports in the slide face. By this arrangement in com-
bination with the transverse slide I obtain one eduction port on each side of
the eduction port for going "ahead," the other two ports serving to conduct
the steam to the back of the piston, or vice versa to reverse the motion. The
transverse slide is formed with four" ports or openings, two in the centre and

page_text: one on each side. Three of these ports or openings are brought into position
with the induction passages to the cylinder to reverse the motion, the fourth
being open to the exhaust. Two of these induction ports are used to start the
engine for going ahead, and in order to reverse the engine the transverse
slide is moved so as to close the two ports for going ahead, thus opening the
other two ports to move the engine backwards. By this arrangement of the
reversing slide the engine can be brought into long or short gear without any
alteration of the slide valve previously described in the first part of my
improvements. Steam is admitted to the transverse slide valve face to
counteract the pressure upon the slide.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Bond in the Great Seal Patent Office on the 12th
October 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
BOND, of Denmark Street, Soho, in the County of Middlesex, Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twelfth day of April, in the year of our Lord One
thousand eight hundred and sixty-six, in the twenty-ninth year. of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
William Bond, Her special licence that I, the said William, my executors,
administrators, and assigns, or such others as I, the said William Bond,
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 Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN THE SLIDE VALVES
AND REVERSING GEAR OF ENGINES WORKED BY STEAM, AIR, OR GASES," upon the
condition (amongst others) that I, the said William Bond, my executors or
administrators, by an instrument in writing under my, or their, or one of their
hands and seals, should particularly describe and ascertain the nature of the
said Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six calendar
months next and immediately after the date of the said Letters Patent.

page_text: NOW KNOW YE, that I, the said William Bond, do hereby declare the
nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say:-
My improvements relate, first, to the mode of arranging the parts of slide
valves of steam or other motive-power engines in order to counteract the
back pressure upon the slide valves of such engines. For this purpose the
slide a (shown in the Drawings hereunto annexed) which opens and closes
the "ports" or steam passages a', a', to and from the cylinder a² is faced up
at the front and back and at each side thereof so as to slide steam-tight
between the face of the ports and the faced up end of a short hollow piston b
arranged in a cylinder 6¹ forming part of the steam chest cover at the back
of the slide a, and through or to which the steam, air, or gas (as the case
may be) is admitted to the induction port or inlet passage. Tho slide a is of
rectangular shape, as shown in Figure 2 and 3 of the Drawings, and is
formed with an opening or openings a*, a*, (between the surfaces of the
slide a, which close and open the ports) for the passage of the stem to the
induction port, the exhaust steam passing away alternately at the outer ends
of the slide a into the steam chest c, and from thence to the exhaust pipe or
passage c'. The hollow piston b at the back of the slide a is furnished with
packing so as to slide in its cylinder b' by the pressure of the steam up to the
faced up surface forming the back of the slide a, the pressure of the steam on
the opposite side counteracting any undue pressure upon the slide, and adjust-
able stops b, be, are (according to the arrangement of parts shown by Figure 4
of the Drawing) arranged to act upon the piston b to prevent its moving out
of position with the slide a; the piston b in this arrangement being furnished
with metallic or other packing 6* to keep it steam-tight. In place of the
packing 6*, and adjustable stops 62, as described in reference to Figure 4, I
prefer to render the cylindrical cover steam-tight by means of a ring b³ of
lead or other comparatively soft metal capable of expanding by the pressure
of the steam to form a tight joint, as shown in Figures 1 and 2 of the
Drawings. The passages a*, a*, through the slide are so arranged that the
exhaust passages, when open for the escape of steam, are of larger area than
they are when admitting steam to the cylinder, the induction passage at this
time being partially covered by the central part of the slide.
arrangement the steam is admitted through the false top or cover
act on both sides thereof, thus relieving the slide a from undue pressure; the
steam being admitted to the cylinder a through the induction port or pas-
By this
so as to

page_text: sages a*, a*, formed in the body of the slide (or through the slide cover), the
exhaust steam escaping through an ordinary exhaust port c¹ alternately
placed in communication with and acting for the time as the eduction port
or exhaust passage by the to-and-fro movement of the slide a.
The second part of my Invention relates to a mode of arranging reversing
gear or apparatus for reversing the movement of engines worked by steam,
air, or gases. For this purpose I arrange a long transverse slide d, Figure 4,
furnished with suitable ports or passages for directing the steam to either side
of the piston as required; such slide being moved (by suitable 'mechanism
through stuffing boxes, as is well understood,) to and fro across the slide
valve jacket and steam ports to open or close the induction and eduction
passages in order to reverse the movement of the engine when required. The
two induction ports to the cylinder are divided by a partition in the centre of
each, thus making four induction ports in the slide face. By this. arrange-
ment, in combination with the transverse slide d, I obtain one induction port
on each side of the eduction port for going "ahead," the other two ports
serving to conduct the steam to the back of the piston, or vice versa, to
reverse the motion. The transverse slide d is formed with four ports or
openings, two in the centre and one on each side; three of these ports or
openings are brought into position with the induction passages to the cylinder
to reverse the motion, the fourth being open to the exhaust. Two of these
induction ports are used to start the engine for going ahead, and in order to
reverse the engine the transverse slide is moved so as to close the two ports
for going ahead, thus opening the other two ports to move the engine back-
wards. By this arrangement of the reversing slide d the engine can be
brought into long or short gear without any alteration of the slide valve
previously described in the first part of my improvements. Steam is admitted
to the transverse slide valve face to counteract the pressure upon the slide.
Having thus described the nature of my Invention, and the manner in
which the same is carried into practice, I would have it understood that I do not
confine myself to the exact details herein described; but what I claim is,-
First, the arrangement of the slide valves of engines worked by steam, air,
or gases, wherein the slide a is formed with an opening or openings com-
municating for the time with the inlet passage, the slide being arranged in
combination with a slide cover b, on both sides of which the pressure is caused
to act equally in order to prevent any back pressure upon the slide a, as herein
described.
Secondly, I claim the mode of arranging the passages in a transverso

page_text: slide for reversing the motion of engines worked by steam, air, or gases, as
herein described.
In witness whereof, I, the said William Bond, have hereunto set my
hand and seal; this Eleventh day of October, in the year of our Lord
One thousand eight hundred and sixty-six.
Witness,.
J. G. TONGUE,
Patent Agent,
34, Southampton Buildings,
Chancery Lane, W.C..
WILLIAM BOND. (L.S.)