Improvements in Rotary Motors, Pumps, Blowers, and similar Engines.
Year: 1897

page_text: Date of Application, 13th July, 1897-Accepted, 26th Feb.,
1898
COMPLETE SPECIFICATION.
Improvements in Rotary Motors, Pumps, Blowers, and similar
Engines.
I, FRIEDRICH HEINRICH EDUARD LEHMANN, of Eilenburg, in the Empire of
Germany, Engineer, 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 :-
In the annexed drawings, Fig. 1-5 shows a rotary engine which can be used for
force or suction of liquids or gases or as a motor.
Figs. 1 2 2 3 4 are cross sections in different positions and Fig. 5 is a longitudinal
section.
It may be mentioned, that either D or S may be the exhaust side and conversely
either S or D the inlet or suction side that is to say the engine may be revolved in
either direction.
If S is suction side, Fig. 2 represents the engine at the beginning of the suction.
The piston Z leaves the chamber K' and thus sucks on by its further movement
from S the medium to be drawn, until the following piston 74, as shown in Fig. 4
cuts off the suction chamber.
The body of gas or liquid enclosed between the pistons Z¹ and Z; Z and Ziv is
brought to the pressure or exhaust side of the revolution of the piston carrier.
In Fig. 4 the piston Z is about to move to bring the chamber behind it into
communication with the pressure or exhaust side, in Figs. 2 and 3 the mixture
contained between the pistons Z and is in communication with the pressure or
exhaust side and in Fig. 1 the piston (Z) is about to again enter the chamber of
the chamber wheel St.
..
The essential and peculiar feature of this apparatus is the circulation channels
or grooves y y in Figs. 1-5 by which the construction differs considerably from all
known apparatus of this class.
If in Fig. 1 and 2 the channels are omitted as shown by the shading as at 310
the following is the result.
When the piston enters into the chamber Kiv of the chamber wheel St the
medium in the chamber can only leave through the slot x; as the body of the
piston is then entering the opening of the chamber the effective area of
the space x is at its minimum, the medium contained in the chamber whether gas
or liquid is forced with great acceleration out of the chamber and the whole liquid or
gas mixture is thus brought into an agitated or accelerated movement.
The time occupied in the entering of the piston is at most 1/12-1/30 of a second
so that a considerable shock will be produced.
On the suction side the same result happens if in Fig. 2 the channel y is
omitted.
As the piston Z¹ leaves the chamber the chamber must be filled again. The gas
or the liquid can only enter through space x; this opening is also at its minimum
when the suction due to the passing out of the piston is at its greatest.
The medium must then fill the chamber with considerably augmented celerity,
or a recoil is effected; in any case a shock is produced. From these quickly
successive shocks, premature wear and considerable consumption of force will result,
for each shock in an engine entails a useless consumption of power.

page_text: In all piston engines such shocks exist and cause not only the early wearing of
the pistons, shafts, bearings, stuffing boxes etc. but also are unfavorable to the
efficiency.
By means of the circulation-channels or passages, these inconveniences are com-
pletely avoided.
For instance in Fig. 1 the medium receives by means of the passage y a more than
sufficient escape, so that compression of the liquid or of gases cannot take place in
the chamber, and thus no acceleration of the whole body of liquid or gas; also in
Fig. 2 the entrance can be effected without shock, as the passage y provides an
entrance of sufficient cross section.
The sucked in liquid or gas undergoes in its movement no change and shocks are
avoided.
In blowers therefore noise also is avoided since such noise is only caused by the
aforesaid movements of the air or gases. Upon the mass of the piston and the
velocity with which it enters the chamber, depends the size of the circulation
channels or passages both in width o, Fig. 1 and in length Figs. 5 and its size is so
measured or adjusted by cocks (Fig. 2) that the gas or the liquid enters and leaves
without shock.
In Fig. 14 the circulation channels or
constructions.
passages are shown in. different
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
An improved rotary engine with circulation channels or passages y which are
produced by perforating or cutting the surface in the interior of the casing against
which the working piston works.
Dated this 13th day of July 1897.
HERBERT HADDAN & Co.,
Agents to Applicant, 18, Buckingham Street, Strand, London.