AN IMPROVED ROTARY ENGINE AND PUMP TO BE DRIVEN BY WATER OR STEAM POWER
Year: 1873

page_text: LETTERS PATENT to James Forbes and John Hamilton, both of
Handsworth, near Birmingham, in the County of Stafford, Engineers,
for the Invention of "AN IMPROVED ROTARY ENGINE AND PUMP TO BE
DRIVEN BY WATER OR STEAM POWER."
Scaled the 20th January 1874, and dated the 29th September 1873.
PROVISIONAL SPECIFICATION left by the said James Forbes and
John Hamilton at the Office of the Commissioners of Patents, with
their Petition, on the 29th September 1878.
We, JAMES FORBES and JOHN HAMILTON, both of Handsworth, near
Birmingham, in the County of Stafford, Engineers, do hereby declare
the nature of the said Invention for "AN IMPROVED ROTARY ENGÍNE AND
PUMP TO BE DRIVEN BY WATER OR STEAM POWER," to be as follows:
.
The present, like many existing rotary engines, is intended to act as a
pump when the central shaft is driven to cause the working of the
internal cylinder within the case and to act as an engine proper, or
power producer or deliverer, when the internal cylinder within the case
is driven by water or steam to cause the working of the central shaft.
Whether for one use or the other it will be convenient herein to
designate it the "engine."
1―
.

page_text: The Invention consists in constructing the internal cylinder of tho
engine with four sliding blades, pallets, or pistons to work and act as
stops across the annular space or pressure chamber between the internal
cylinder and the case.
The accompanying Drawing will explain the novelty of the Invention
and mode of carrying it into effect.
Figure 1 is a cross section of Bennison's engine (sec Specification in
pursuance-of- Letters -Patent-No.-3403,-A.D. 1868), which for present
purposes may be taken as a type of existing engines upon which tho
present Invention is an improvement; Figure 2 is a corresponding cross
section of our improved engine.
In the former Figure are represented two sliding blades, pallets, or
pistons q. In the latter Figure four of these are represented, the
increased number enabling us to work the engine more evenly and make
use of double the quantity of steam or water as the motive agent within
a stated period.
In both Figures h is the central shaft; i, the internal cylinder; g, tho
external cylinder or case; k, annular space; o, o, cams for forcing the
blades, pallets, or pistons q inwards, and p other (smaller) cams for
forcing them outwards or across the space k at the desired point or
-positions-during the revolution of the shaft and cylinder i
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said James Forbes and John Hamilton in the Great
Seal Patent Office on the 24th March 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JAMES 2
FORBES and JOHN HAMILTON, both of Handsworth, near Birmingham,
in the County of Stafford, Engineers, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-ninth day of September, in the year
of our Lord One thousand cight hundred and seventy-three, in the thirty- 30
seventh year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto us, the said James Forbes and John Hamilton, Her
special licence that we, the said James Forbes and John Hamilton,

page_text: our executors, administrators, and assigns, or such others as we, the
said James Forbes and John Hamilton, our 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 "AN IMPROVED ROTARY ENGINE AND PUMP TO
BE DRIVEN BY WATER OR STEAM POWER," upon the condition (amongst others)
that we, the said James Forbes and John Hamilton, our executors
or administrators, by an instrument in writing under our, 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.
NOW KNOW YE, that we, the said James Forbes and John Hamilton,
do hereby declare the nature of our said Invention, and in what
manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:-
The present, like many existing rotary engines, is intended to act as a
pump when the central shaft is driven to cause the working of the
internal cylinder within the case, and to act as an engine proper or
power producer or dolivorer when the internal cylinder within the case
is driven by water or steam to cause the working of the central shaft.
Whether for one use or the other it will be convenient herein, to
designate it the "engine."
The Invention consists in constructing the internal cylinder of the
engine with four sliding blades, pallets, or pistons, to work and act as
stops across the annular space or pressure chamber between the internal
cylinder and the case.
Bennison's engine (see Specification in pursuance of Lotters Patent
No. 3403, A.D. 1868) may be taken as a type of the existing engines,
upon which the present Invention is an improvement.
-
In Bennison's engines are two sliding blades, pallets, or pistons, in
3 ours there are four, the increased number enabling us to work the
engine more evenly and make use of double the quantity of steam or
water as the motive agent within a stated period.

page_text: Tho accompanying Drawing is furnished in explanation of tho con-
struction of the improved engine.
Figures 1 and 2 are vertical sections of the engine, and the other
Figures represent detached parts. Similar letters of reference are used
to denote the corresponding parts throughout.
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g.is.the external cylinder, the end plates 9* of which furnish bearings
for the central shaft h, and i is the internal cylinder (shewn detached in
the sections, Figures 3 and 4), keyed on to the shaft and turning
therewith; % is the annular space or pressure chamber between the two
cylinders; o, o, are two cams placed inside the outer cylinder (shewn 1
detached in Figures 5 and 6) for forcing the four blades, pallets, or
pistons q, q, inwards, cach twice during a completo rovolution of tho
inner cylinder in which they are free to slide in grooves as represented,
and p is another cam picce or cam (shown detached in Figures 7 and 8)
for forcing them cach. twice during a complete revolution outwards 1
across the space k. The cams are stationary and are so shaped and
placed as to perform their office at the proper times, the cam p being
supported by the shaft and its effective curved parts p* lying within a
recess (see Figure 4) in the inner cylinder..
:
In Figure 2, 93, 9, are studs or steady pins put into one of the end 2
-plates of the outer-cylinder-and penetrating into holes in tho
lugs p, p, of the cam piece p to hold or prevent it from turning. The
dotted lines,, show position of the cams o.
Figures 9 and 10 shew detached views of one of the pistons a on
which q* denotes the tail piece or part acted upon by the cam 2
surfaces p* and q³, q², the parts or places acted upon by the cams o, o.
In witness whereof, we, the said James Forbes and John Hamilton,
have hereunto set our hands and scals, this Twentieth day
of March, in the year of our Lord One thousand cight hundred
and seventy-four.
3