CERTAIN IMPROVEMENTS ON ROTATORY STEAM ENGINES
Year: 1822

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
BAINBRIDGE, of Bread Street, in the City of London, Merchant, send greeting.
WHEREAS His most Gracious Majesty King George the Fourth did, by
His Letters Patent under the Great Seal of that part of the United Kingdom
of Great Britain and Ireland called England, bearing date at Westminster, the
Sixteenth day of December (1822), in the third year of His reign, give and
grant unto me, the said John Bainbridge, my exors, adññiors, and assigns, His
special licence, full power, sole privilege and authority, that I, the said John
Bainbridge, my exors, adññiors, and assigns, during the term of years therein
mentioned, should aud lawfully might make, use, exercise, and vend, within
England and Wales and the Town of Berwick-upon-Tweed, and also in all
His Majesty's Colonies and Plantations abroad, an Invention (communicated
to me by Amos Thayer, junior, of the City of Albany, in the United States of
America, Mechanist,) of "CERTAIN IMPROVEMENTS ON ROTATORY STEAM ENGINES;"
in which said Letters Patent is contained a proviso that if I, the said John
Bainbridge, shall not particularly describe and ascertain the nature of the
said Invention, and in what manner the same is to be performed, by an instru-
ment in writing under my hand and seal, and cause the same to be inrolled
in His Majesty's High Court of Chancery within six calendar months next

page_text: aud immediately after the date of the said Letters Patent, that then the said
Letters Patent, and all liberties and advantages whatsoever thereby granted,
shall utterly cease, determine, and become void, as in and by the same,
relation being thereunto had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
John Bainbridge, do hereby declare that the nature of the said Invention, and
the manner in which the same is to be performed, are particularly described
and ascertained in and by the Drawings hereunto annexed, and the following
description thereof, that is to say:―
The improvements on rotatory steam engines" claimed by me, consists in
a method of producing a rotary motion by the direct pressure of steam exerted
against two radient pistons, placed at right angles to each other, which act
within two hollow metallic boxes, divided by a partition; and through this
partition an aperture is formed for admitting the steam from one box to the
other. These boxes, as well as the other parts of the machine, may be made
of cast iron, or other fit and proper materials.
Fig. 1 of the Drawings represents the appearance of the external part of
the engine; a is one box, b is the other.
Fig. 2 is a side view of the engine, the outer cap or lateral plate being
removed in order to shew the internal form of the box and the action of the
piston within.
Fig. 3 is a cross section of the boxes and partition; the respective letters
referring to the same parts of the engine in each Fig. Steam from a boiler
is made to pass through the pipe c, and by the nozzle d enters the box or
chamber a, where, exerting its expansive power, the radient piston e is forced
round in the direction of the arrow. f is the rotatory axle; and g is a circular
block circumscribing and revolving with it. Through both of these the
piston e slides, by its ends pressing against the curved part of the interior of
the box a; when the force of the steam has carried the piston e past the per-
pendicular position, and beyond the opening of the passage h, the steam
escapes through this passage into the second box or chamber b, the form and
position of which is shewn by the dotted lines in Fig. 2. Here the steam
exerts itself against the piston i, i, seen also by dots at right angles to the
piston e, and which has now obtained an horizontal position, when, by a similar
operation, this piston i is carried forward until it passes the eduction pipe or
exit passage k, through which the steam now proceeds to the condenser, or
into the open air. The piston e having now arrived at the horizontal position
first described, as at Figs. 2 and 3, the reverse end of it acts against the curved
interior of the box; and the steam passing through the entrance pipe c at the
.

page_text: nozle d, as before described, forces the piston forward. Thus, by the pressure
of the steam alternately upon the pistons e and i, the continued rotation of the
axle fis produced; and this being by the ordinary means of geer connected to
other machinery, gives the power and rotative motion.
Having thus described the general action of this engine, a particular
description of the construction of the different parts becomes necessary.
Fig. 4 represents a portion of the main shaft or axle f, attached to which are
the circular blocks g, g.
Fig. 5 is one of the sliding pistons, in which the grooves are seen, intended
to receive the packing.
Fig. 6 exhibits the two parts of the middle partition or parting cap; and
Fig. 7 is an edge view shewing their thickness.
cap
Fig. 8, one of the boxes in which the piston works. The partition or parting
is formed by two flat pieces of metal with a recess or hollow in the centre,
intended to contain packing; and when this parting cap is put together, so as
to embrace the shaft f, the packing is pressed down close to the shaft by means
of the four plugs m driven into the packing holes, and secured by screws; one
of which plugs is seen withdrawn at Fig. 9. Packing of course must be
introduced between the junction of the parting cap, or they may be luted
together. The pistons are to be furnished with packing, secured into the
groove upon their edge, which prevents the steam from passing either at their
sides or ends. Friction rollers n, n, are introduced into the blocks on the sides
of the apertures, against which the pistons are pressed to assist their sliding.
The boxes, as Fig. 8, are now to be attached to the parting cap, and bolted
thereto, in the manner shewn at Figs. 1, 2, and 3. The whole being thus
secured and rendered perfectly steam-tight is in complete order for operation,
as described above.
The principle of this rotatory engine does not confine its construction to
any particular dimensions; that will of course depend upon the power
required, and the relative diameters of the blocks to the capacity of the boxes,
as well as the breadth of the pistons, and is altogether discretionary; and an
ordinary condensing air pump and fly wheel may be employed, if required.
The engine, when in action, produces a rotatory motion as its first movement,
which is applicable to the moving of any description of machinery requiring a
rotatory power. The form of the boxes in which the pistons work; the com-
bination and union of two of those boxes together, so as effect the reciprocal
action of the pistons, and thereby producing a continued rotatory motion; and
the particular form and construction of the parting cap or partition betwixt
the two boxes, as described above, are the particular parts claimed by me

page_text: under this Patent, the bolting, packing, &c., &c., being common to other
steam engines heretofore in use.
In witness whereof, I, the said John Bainbridge, have hereunto set my
hand and seal, this Fourteenth day of June, in the year of our Lord
One thousand eight hundred and twenty-three.
AND BE IT REMEMBERED, that on the Fourteenth day of June, in
the
year of our Lord 1828, the aforesaid John Bainbridge came before our
said Lord the King in His Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained and specified, in form
above written. And also the Specification aforesaid was stamped according
to the tenor of the Statute made for that purpose.
Inrolled the Fourteenth day of June, in the year of our Lord One
thousand eight hundred and twenty-three.