Improvements in Rotary Blowing or Blast Engines.
Year: 1897

page_text: Improvements in Rotary Blowing or Blast Engines.
I, GEORG HEINRICH LIISSEN, of the City of Hanover, in the Kingdom of Prussia.
and German Empire, Manufacturer, do hereby declare the nature of this invention
to be as follows:-
My invention relates to improvements in rotary blowing or blast engines of the
type in which wings or vanes revolve round a stationary cylinder and engage with
indentations or cavities in a second cylinder which is thereby rotated in the
opposite direction.
In such engines hammering or concussion occurs which not only reduces the
useful effect of the engines but also by the noise causes. great discomfort and
annoyance to the people around them. This hammering or concussion is occa-
sioned by the passage of each wing through one of the indentations or cavities
causing the cavity to open suddenly towards the suction or inlet side and thereby
allowing the compressed air to escape suddenly.
To overcome this defect the ordinary straight wings and corresponding in-
dentations are now replaced according to my invention by wings and cavities in the
form of screw threads.
By this improvement when the connection on the blowing side with the cavity
is approaching the shut off the cavity begins to open gradually towards the inlet
side and consequently only a gradual flow of compressed air can take place on
this side whereby all concussion and noise is obviated and further on account of
their form the wing and cavity do not catch suddenly but gradually and smoothly.
1 d. of T 1907
..
Improvements in Rotary Blowing or Blast Engines.
I, GEORG HEINRICH LHSSEN, of the City of Hanover, in the Kingdom of Prussia
and German Empire,, Manufacturer, do hereby declare the nature of this invention
and in what manner the same is to be performed; to be particularly described and
ascertained in and by the following statement:
My invention relates to improvements in blowing or blast engines of the
type in which wings or vanes revolve round a stationary cylinder and engage with
indentations or cavities in a second cylinder which rotates in the opposite direction.
In such engines hammering or concussion occurs which not only reduces the
useful effect of the engines but also by the noise causes great discomfort and
annoyance to the people around them. This hammering or concussion is occa-
sioned by the passage of each wing through one of the indentations or cavities
CD
017

page_text: causing the cavity to open suddenly towards the suction or inlet side, and thereby
allowing the compressed air contained in the cavity to escape suddenly..
To overcome this defect the ordinary straight wings and corresponding in-
dentations are now replaced according to my invention by wings and cavities in the
form of screw threads.
In the accompanying two sheets of drawings
Figs. 1 and 2 are sectional views of the main portion of one type of an ordinary
blast engine.
Figs. 3, 4 and 5 represent sectional views of a blast engine made according to
my invention. These views show the engine in the same position as that repre-
sented in Fig. 2. Fig. 3 being a section on the line A B, Fig. 4 a section on the
line CD, and Fig. 5 a section on the line E F, all on Fig. 7.
Fig. 6 is an end view of the complete blast engine and Fig. 7 is a plan view,
partly in section of Fig. 6.
:
In Figs. 1 and 2,- - a are two ordinarily shaped wings or vanes mounted in
a casing m and arranged to be revolved around a stationary cylinder c. When
the engine is set in motion the wings or vanesa a enter cavities b in the rotating
cylinder each cavity communicating with the pressure side of the engine.
In this construction of blast engine there is considerable tension in the space B1
because the suddenness and rapidity with which each wing or vane enters its
cavity necessarily produces a compression of the air and as the wing rotates further
the cavity opens abruptly in the direction of the inlet or suction side and through.
the wide opening thus suddenly, made the compressed air in the cavity rushes out
on the suction side and causes a knock or concussion to take place.
To remedy this defect I dispense with straight wings such as a and the corres-
ponding cavities 6 and in their stead I propose to employ wings and cavities made
in the form of screws threads as shown best in Figs. 6 and 7.
In Figures 3 to 7,-M designates the casing, the stationary cylinder, F the
screw shaped wings which are carried round the cylinder C, H the cavities in a
rotating cylinder W; on a shaft or axle I is fitted a pulley J and a spur wheel K
which gears into a spur wheel L secured upon a shaft O which carries a cylinder W
provided with corresponding screw shaped cavities H. The wings F are secured
upon a disc S which is fixed upon the shaft I which passes freely through the
stationary cylinder cylinder C.
It will be seen from the drawings that at the moment when the connection on
the blowing side with the cavity is approaching the shut off, the cavity H towards
the inlet on the suction side begins to open gradually and consequently only a
gradual flow and discharge of compressed air from the cavity towards the inlet can
take place on this side whereby all concussion and noise is obviated and further,
on account.of their form, the wing and cavity do not catch suddenly but gradually
and smoothly.
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed I declare that what I
claim is
In a blast engine of the type indicated, the combination with screw shaped
wings arranged to revolve around a stationary cylinder in a hollow casing, of
corresponding screw shaped cavities formed in a cylinder arranged to rotate with
the revolving wings substantially as and for the purposes herein set forth.
T
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H. B. BARLOW & GILLETT,
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