IMPROVE- MENTS IN BLOWING ENGINES
Year: 1860

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields,
in the County of Middlesex, and of 166, Buchanan Street, in the City
of Glasgow, North Britain, Gentleman, for the Invention of "IMPROVE-
MENTS IN BLOWING ENGINES."-A communication from abroad by Edouard
Francois Fossey, Paris, in the Empire of France, Engineer.
Sealed the 1st June 1860, and dated the 28th January 1860.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of Patents, with his Petition, on
the 28th January 1860.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, and of 166, Buchanan Street, in the City of Glasgow, North
Britain, Gentleman, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN BLOWING ENGINES," a communication from abroad by
Edouard Francois Fossey, of Paris, in the Empire of France, Engineer, to be
as follows:-
This Invention relates to a peculiar construction and arrangement of blowing
engine or machine, applicable either to large works, such as blast furnaces,
or as small forge blowing machines. According to this Invention, the
objectionable use of clack or slide valves is dispensed with, such means of dis-
tribution or direction of the air being replaced by the application to each end
of the blast cylinder of a rotating disc or outer cover, provided with alternate
radiating openings and closed channels or air passages. These discs rotate in

page_text: contact with the fixed ends of the cylinder, which have a number of radiating
openings made in them corresponding to the openings in the rotating discs, so
that when the two sets of openings coincide, as they will intermittantly do
during the continued rotation of the discs, there will be a free communication
between that end of the cylinder and the atmosphere, whilst the disc on the
opposite end of the cylinder is so timed in its rotation, that its air channels
will be over the openings in the fixed end of the cylinder; these channels
when in this position form a communication from the interior of the cylinder
to an annular chamber which surrounds the cylinder, and communicates to the
main blast pipe. The discs are rotated by gearing so proportioned in relation
to the stroke of the piston, that that end of the cylinder from which the piston
is receding will be open to the atmosphere, and consequently air will be drawn
therein, whilst the end towards which the piston is approaching will be in
communication by means of the radiating air channels with the annular space
leading to the blast pipe. The piston may be actuated direct from a steam
cylinder, or from a crank shaft, driven either by a strap and pulley, or by the
piston rod of a steam engine.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Henry Johnson in the Great Seal Patent Office on
the 27th July 1860.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
and of 166, Buchanan Street, in the City of Glasgow, North Britain, Gentle-
man, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-eighth day of January, in the. year of our
Lord One, thousand eight hundred and sixty, in the twenty-third year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said John Henry Johnson, Her special license that I, the said
John Henry Johnson, my executors, administrators, and assigns, or such
others as I, the said John Henry Johnson, my executors,. administrators,
or 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 law-
fully might make, use, exercise, and vend, within the United Kingdom of
Great Britain and Ireland, the Channel Islands, and Isle of Man, an Inven-
tion for "IMPROVEMENTS IN BLOWING ENGINES," a communication from abroad

page_text: by Edouard François Fossey, of Paris, in the Empire of France, Engineer,
upon the condition (amongst others) that I, the said John Henry Johnson,
by an instrument in writing under my hand and seal, 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.
NOW KNOW YE, that I, the said John Henry Johnson, do hereby
declare the nature of the 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 accompanying Drawings, and
to the letters and figures marked thereon, that is to say :-
The said Invention relates to a peculiar construction and arrangement of
blowing engine or machine applicable either to large works, such as blast
furnaces, or as small forge blowing machines. According to this Invention,
the objectionable use of clack or slide valves is obviated, with such means of
distribution or direction of the air being replaced by the application to each
end of the blast cylinder of a rotating disc or outer cover, provided with
alternate radiating openings and closed channels or air passages. These discs
rotate in contact with the fixed ends of the cylinder, which have a number of
radiating openings made in them corresponding to the openings in the rotating
discs, so that when the two sets of openings coincide, as they will intermittently
do during the continued rotation of the discs, there will be a free com-
munication between that end of the cylinder and the atmosphere, whilst the
disc on the opposite end of the cylinder is so timed in its rotation, that its air
channels will be over the openings in the fixed end of the cylinder. These
channels when in this position form a communication from the interior of the
cylinder to an annular chamber which surrounds the cylinder, and com-
municates with the main blast pipe. The discs are rotated by gearing so
proportioned in relation to the stroke of the piston, that the end of the cylinder
from which the piston is receding will be open to the atmosphere, and con-
sequently air will be drawn therein, whilst the end towards which the piston is
approaching will be in communication by means of the radiating air channels
with the annular space leading to the blast pipe. The piston may be actuated..
direct from a steam cylinder, or from a crank shaft, driven either by a strap.
and pulley, or by the piston rod of a steam engine.
And in order that the said Invention may be fully understood, I shall now
proceed more particularly to describe the same, and for that purpose I shall
refer to the several Figures on the Sheet of Drawings hereunto annexed, the

page_text: same letters of reference indicating corresponding parts throughout all the
Figures.
Figure 1 represents a longitudinal vertical section of one arrangement of
blowing engine in complete working order; Figure 2 is a corresponding plan
of the same; and Figure 3 is a half end elevation and transverse section of
the blowing cylinder. The rest of the Figures are details, which will be
herein-after fully described and referred to.
A is the enclosed or jacketed blowing cylinder, cast in one piece with the
outer cylinder or jacket, the small cross pieces or ribs a serving as a con-
nection between the inner and outer cylinders. The ends B of the inner
cylinder are cast with stuffing boxes upon them, and with inlet apertures b, b,
and their diameters are equal to the external diameter of the inner cylinder.
These covers are fixed tight by means of ground joints and screws, and offer in
conjunction with the ends of the outer cylinder a perfectly plane surface for the
reception of the discs, an annular space being left between the two cylinders.
The blowing piston C fixed on its rod is provided on each side with pro-
jections c, c, which partly fill the orifices b, b, in the cylinder covers B, B, in
order to reduce as much as possible the otherwise lost space at each stroke of
the piston, as is shewn by the detail front view of the piston at Figure 5, and
section at Figure 7. D, D, are the rotating discs, having inlet orifices b', ',
formed in them, and corresponding with the openings b, b, in the cylinder
covers B, and having also intermediate outlet orifices d, d, which open into the
annular space e, and consequently communicate with the lateral outlet pipe f
on the internal cylinder. These discs are provided with teeth on their
peripheries, in order to receive a rotatory motion round the stuffing boxes
of the end covers B which form the fixed axes of rotation. They are kept
pressed against the surfaces of the covers B by the rings g, g, which are bolted
to the edge of the external cylinder. The bolts so employed are provided
with washers of caoutchouc, in order to prevent a too powerful gripping of the
discs between the rings g and the ends of the external cylinder. The horizontal
shaft E carries two spur pinions K, K, which gear with the teeth on the discs
D, D. This shaft carries at its opposite end a bevel wheel L, fixed to a
collar by two bolts, so as to enable the orifices of the discs to be regulated or
adjusted forwards or backwards. The crank shaft F is driven by any suitable
prime mover, through the intervention of a strap and driving pulley, as shewn,
or it may be driven direct from a steam engine, the piston of which may, if
desired, be fitted on to the same rod as the blowing piston. This shaft carries
at one end a bevel pinion gearing with the bevel wheel which drives the discs.
G is the cast-iron bed plate upon which the entire machine is secured.

page_text: Figure 4 is a detail of the interior face of one of the discs D, showing the
inlet orifices and the outlet orifices d, which latter unite in the annular
space e. Figure 5, already referred to, is a view of one of the sides of
the blowing piston C with its projections c, c. Figures 6, 7, and 8,
represent in circular section along the dotted line l, l, in Figure 3 the discs
D, D, placed against the covers B, B, in their different positions. Figure 6
shows the inlet orifices full open when the piston has arrived at the middle of
its stroke in one direction. Figure 8 shows the outlet orifices full open when
the piston has attained the middle of its stroke in the opposite direction and
Figure 7 shews the piston at the end of its stroke, or on the dead centre when
the orifices are changing, so as to open the inlets.
i
The advantages obtained by the peculiar construction of this blowing
machine are,-
First, the power of working it at the highest possible speed attainable from
a crank, the discs forming no obstacle, by reason of their comparatively slow
and regular rotation, consequently the size of large or powerful blowing
engines may be considerably reduced.
Second, the reduction to any desired extent of the lost space at the end of
each stroke of the piston, as by the application to the covers of the cylinder
and the faces of the piston of an elastic material, a complete contact may be
obtained between them, whence it follows that every particle of air will be
expelled.
Third, the great simplicity of its construction.
I may here observe, that the areas of the inlet and outlet orifices are equal
to one-fifth of the transverse section of the cylinder or surface of the piston,
whilst in the case of slide valves it is with great difficulty that such orifices
are made to attain one-eighth or one-seventh of the cylinder's area in large
engines. In large engines constructed after this Invention, if it is desired to
reduce still further the speed of rotation of the discs, 12, 16, 24, or more
orifices may be made in them in place of 8, without injury to the good working
effects of the machine. In this case it will be necessary to change the pro-
portions of the gearing which rotates the discs.
Having now described and particularly ascertained the nature of the said
Invention, and the manner in which the same is or may be used or carried
into effect, I would observe in conclusion, that what I consider to be novel
and original, and therefore claim as the Invention secured to me by the
herein-before in part recited Letters Patent is,―
First, the general construction and arrangement of blowing engines, as
herein-before described.

page_text: Second, the application and use to and in blowing engines of perforated
rotating discs in lieu of clack or slide valves, as herein-before described.
In witness whereof, I, the said John Henry Johnson, have hereunto
set my hand and seal, this Twenty-sixth day of July, One thousand
eight hundred and sixty.
J. HENRY JOHNSON. (L.S.)