An Improved Rotary Expansion Engine.
Year: 1899

page_text: Date of Application, 16th Oct., 1899-Accepted, 18th Nov., 1899
COMPLETE SPECIFICATION.
An Improved Rotary Expansion Engine.
We, CARL ARTHUR SCHOPPER, Engineer, and ALFRED WILHELM HERMANN
RÖDER, Machine Constructor, both of No. 3, Wilhelminenstrasse, Kiel, in the
Empire of Germany, 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:-
1
In order to obviate the concussions occurring in connection with cylinder
machines, caused by reversing the direction of motion of the steam-piston, and
for which, as is known, a very large portion of the generated power must be
employed for the purpose of effecting transmission, rotary machines have been
produced, in which the rotary pistons transmit the power to the driving shaft.
If these machines have already secured the attention of all persons skilled in the
art, by reason of the principle employed, the new invention, which, in com-
parison with existing rotary machines, is far more complete, will receive even
greater attention, as it embodies an idea whereby the working capacity of the
machine is made greater than any hitherto attained.
In the present invention, the uniform running of the machine, as well as
a better transmission of power, is assured by the arrangement whereby a rotary
cylinder fixed to a shaft exercises through its total weight its full influence on
the motion and on the easy action of the machine. This rotary cylinder is set in
motion in the following manner:-Partitions or walls are arranged in the
same, which serve as working surfaces for the steam, a number of slides, which
are seated in a fixed frame, alternately entering the cylinder, whereby shut-off
steam-chambers are created between the walls and the slide, and in which chambers
the steam can exercise its pressure on the sides, or walls of the cylinder, so that,
hereby the cylinder is kept constantly rotating.
The accompanying drawings illustrate the new machine.
Sheet 1, showing the general arrangement and Sheet 2, the regulating arrange-
ment for the one pair of slides.
On the driving shaft of the engine, which transmits the power to the working
machine which is driven by the engine, is a steam cylinder a actuated by the
steam and firmly connected with the shaft. This steam cylinder a is closed
all round except the inside and moves on a fixed frame b. In the cylinder are
two fixed walls or partitions a¹ a² corresponding exactly with the size of the
cylinder cross section. Above and below, in the frame b two slides c c and d d¹
are arranged, which are alternately carried into the cylinder a by means of the
eccentric mechanism actuated by the driving shaft, so that when the slide c_is
pushed in, the slide c¹ is also introduced; the two slides d acting just as the
two slides c c¹.
In consequence of a slide being introduced into the cylinder at the same time,
above and below, closed chambers are created between the slides and the walls, of
which chambers two are connected with the inlet channels e e¹ whilst the two
other steam chambers are connected with the exhaust steam channels ff. By an
alteration in the steam conduits, the active steam channels e el being converted
into exhaust steam channels, and the exhaust steam channels f f being allowed
to act as active steam channels, the engine is caused to rotate in the opposite
direction, to that shewn in the drawing. For this purpose, the slide boxes f
are attached, which by means of their slides, that are adjustable by a hand-lever
common to both enable the reversing to be effected.

page_text: a
The entry of steam could be regulated by an arrangement under which the
steam, before passing these slide-boxes cf would be forced to pass through
special slide or valve, which would open twice at each rotation of the engine,
so that the steam could only flow through to the cylinder when it is required
to produce an effect. By means of a simple steam valve which may be arranged
in front of the special slide or valve, the admission of steam from the boiler can
be effected or stopped.
On Sheet 1, of the drawings, Fig. 1, is a front view of the machine partly in
section.
Fig. 2, is a side-view in section along the line -, when the slides & dare
introduced into the steam-chambers.
Fig. 3, is likewise a side view in section along the line y-y when the slides cc¹
are outside of the cylinder.
Fig. 4, is a sectional plan of Fig. 1.
In order that the movement of the slides may be accurately shewn, the regula-
ting contrivance for the one pair of slides c c is illustrated on Sheet 2, which
slides care temporarily (or from time to time) introduced into the cylinder a
by the arrangement of a pair of eccentrics o o' and suitable connecting rods.
The regulating of the pair of slides c c is effected as follows:-
On the driving-shaft of the engine inside the fixed frame b is a toothed wheel h,
which engages with two other toothed wheels h¹². The two latter wheels have a
circumference of half the size of that of the wheel h, as two fixed walls or
partitions are arranged in the cylinder a. Upon the wheel h being rotated once,
the two small wheels hh2 rotate twice, thus each of the wheels acts for one half
of the cylinder. Two eccentrics o p and o¹ 7 are each connected with one small
wheel, these eccentrics being actuated by the rotation of the toothed-wheels. Of
the two pairs of eccentrics the two eccentrics o o' actuate the slides c.c' whilst
the two other eccentrics ? bring about the introduction of the slides d d into the
cylinder.
On Sheet 2 of the drawings, as already mentioned, the one eccentric mechanism
is illustrated, which regulates the two slides c c. Therefore, it is unnecessary to
illustrate the eccentric mechanism for the slides as the function of the latter
is precisely the same as that of the eccentrics o o¹; the whole difference in the effect
of the two pairs of eccentrics only consists in the eccentrics p p being set back in
relation to the eccentrics o o' to the extent of 125°; otherwise the effect is the
same. In consequence of the fact that the eccentrics first exercise the same
effect after the eccentrics o o¹, after a rotation of 125°, the result is produced
on the cylinder that, as the course is here reduced to the half, such course is
only equal to an arc of 6210. Thus the slides & d' effect 6210 after the slides c c¹
exactly the same movement.
66
29
The eccentric rods of the eccentrics o¹ run upwards, and are seated so as to
oscillate freely in guide-shoes kk moving upwards and downwards in guides i i.
A stay serves to connect the two guide-shoes. By this stay, the slides c c¹
are moved into and out of the cylinder through the medium of a lever with two
unequal (or dissimilar) arms m m. The eccentric is arranged at an angle of
1250 in relation to the eccentric o, and for the following reasons:-
::
Assuming that the course on the sliding way, which is transmitted to
the same by the eccentrics o o¹ be divided into four parts and the limits on each
side are indicated by the numerals 1, 2, 3, 4, (sec Sheet 2 of the drawings),
whilst in Fig. 5, the guide-shoes are in the positions 1, it will be seen
that the eccentric is in its highest position, whereas the eccentric o is placed
125° below in the direction of the arrow. If now the engine be rotated to the
extent of 270, the small tooth-wheels 2 are moved further to the extent
of 55°. The result hereby attained is that the guide-shoes k¹ move on the guides
from 1 to 2.
The stay of the guide-shoes k k in being pushed from 1 to 2, actuates a lever m
with unequal (or dissimilar) arms, which causes the slide to enter very quickly

page_text: into the cylinder. The lever m is connected by means of a connecting rod
which
runs downwards, with a lever n having unequal (or dissimilar) arms, whereby,
the lever m having introduced the slide c, the slide c¹ actuated by the lever n, is also
quickly pushed into the cylinder a, so that the steam can act on the walls of the
cylinder and cause the latter to rotate rapidly. The slides c c¹ remain during a
rotation of the small wheels 2 of 125° in the cylinder, that is, a stretch of
620 on the cylinder circumference. The eccentrics o o¹ now reach, after a
complete revolution of 180°, the position 3 (see Fig. 7). Owing to the guide-
shoes being uniformly pushed up and down any influence of the stay lon
the slides c c is avoided.
If however, the eccentrics o o are rotated again to a further 55°, the guide-
shoes will be uniformly pushed in one direction, in this instance from 3 to 4,
(see Fig. 8); in consequence of this, also the levers m n will be actuated and the
slides will leave the cylinder a.
From the position of the slides in Fig. 8, the latter after the rotation of the
eccentric to the further extent of 125°, will remain outside the cylinder, as
during this rotation the eccentric has moved to the same extent upwards as the
cylinder e downwards. Hereby, as can be easily seen, a working path of 6210,
for the steam results.
In order now to increase this working area of the steam, so that a favourable
effect may be secured it is advisable, as provided in the present case, to introduce
a second pair of slides d d', which are actuated by a second pair of eccentrics p p².
This pair of eccentrics 7 p¹ being set back 125°, execute exactly the same move-
ment as the eccentrics o o', only reckoned on the circumference of the cylinder
to the extent of 6210 later, so that, after the slides are moved out of the
cylinder a, the slides are introduced into the same. whereby the working
course of the steam is raised 6210, and therewith a working course of the steam
of 125° results on each side for each half of the cylinder. In this course the
steam can thus exercise an effect on each side through the steam inlets e e¹, whilst
the exhaust steam on the other side of the walls is either carried off into the open
air through the outlet channels f f¹ or conducted through the same to the con-
denser. In Fig. 9, on Sheet 2, the position of the slide regulating arrangements
one behind the other is also shewn in side, view, which view would correspond
with that of Fig. 8.
The employment of the rotary cylinder considerably facilitates the action of
the steam, as it has the effect of a fly-wheel. The acceleration which is imparted
to the cylinder by the rotation, contributes not a little to considerably reducing
the filling for the cylinder. whereby it is evident that no small economy of
steam is effected as compared with the cylinder machines and the rotary engines
hitherto known.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is :-
The improved rotary expansion engine, in which the rotary cylinder a on the
circumference of a fixed frame bis set in rotation in such a manner that the
incoming steam can exercise its effects on fixed walls or partitions a¹ a² of the
cylinder a, so that the movable slides c c or dare introduced by means of
suitable apparatus alternately, and in pairs, into the cylinder a. whereby special
steam chambers are created for the action of the active steam, and for the exhaust,
substantially as shewn and described.
Dated this 16th day of October 1899.
HUGHES & YOUNG,
55 and 56, Chancery Lane, London, W.C.. Agents for Applicants.