An Improved Steam-turbine Wheel.
Year: 1894

page_text: Date of Application, 5th Mar., 1894-Accepted, 28th Apr., 1894
COMPLETE SPECIFICATION.
An Improved Steam-turbine Wheel.
I, EBERHARD SEGER, of 40 Kammakaregatan, Stockholm, in the Kingdom of
Sweden, 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 :—
This invention has for its object to construct steam-turbine wheels in such a
manner, that they shall be simple, cheap and light.
In the accompanying drawing,
Figure 1 is a vertical section of two turbine-wheels arranged according to my
invention and placed one above the other.
Figure 2 is a front elevation of the same with the wheel-ring partly removed.
Figure 3 is a plan view of such a wheel.
Figure 4 illustrates the form of the paddle-blanks.
Figure 5 is a sectional view of a part of my improved turbine-wheel with an
inserted paddle, but without the outer wheel-ring.
Figure 6 is a side elevation of a part of such a turbine-wheel with paddles,
illustrating two different steps of the operation of fastening the latter.
Figure 7 shows a part of such a turbine-wheel with the paddles fixed by riveting,
and
Figure 8 shows the outside of a part of the wheel-body with notches for the
paddles, some of the paddles being inserted.
The paddle-blanks a, which may be punched out of thin sheet-iron plates or of
plates of some similar material, have preferably a substantially rectangular form
(Figure 4), with a notch bin its undermost side. The lower corners of this
rectangle may be cut off (as is illustrated by Figure 4), or they may be formed in
some other way in such a manner, that they do not overlap the edge of the wheel-
body when the undermost part of the paddle-blank is bent as will be hereinafter
further described. The body of the wheel has an I-shaped section (Figure 5) and
at the two edges of the wheel-ring e there is a number of notches d (Figures 2, 8),
of which those at the one edge converge towards those of the other edge, without
however meeting the same. Into the said notches the flaps a on both sides of the
notch bare inserted (Figures 5, 8), the paddle-blank being previously somewhat
curved (Figure 8). If the turbine is a compound turbine, consisting of two turbine-
wheels, the one above the other (as illustrated in Figures 1 and 2), the notches d of
the upper wheel must have a sharper convergence than those of the lower wheel.
After the insertion of the paddle-blanks in the notches, the ends of the flaps x
projecting beyond the inside of the wheel-ring are bent against the inside of that
ring (Figure 6), thus causing the paddles to be securely held in position even
at the greatest velocity of the wheel. In order to strengthen still further this
fastening, rings e may be placed inside the bent paddle-ends (Figures 1, 3) and
a ring may also be shrunk on around the outer-ends of the fixed paddles
(Figures 1, 3), care being taken, to give the paddle-ends such a form either convex
or concave, that the wheel-ring during the shrinking-on obtains a corresponding
form and is thus more securely held in position.
Instead of bending over the inner ends of the paddle-blanks (Figure 6), they
may be fastened to the wheel-body by riveting their ends as illustrated in
Figure 7.

page_text: Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. In steam-turbines, the combination of a wheel-body, the ring (c) of which at
both its edges has notches (d) cut out obliquely and converging towards each other,
and of curved paddle-blanks (a), which at their lower ends have a notch (b) and
flaps (x), designed to be inserted into the notches in the ring of the wheel.
2. In such turbine-wheels the combination of the paddles (a) with ends projecting
inside the wheel-ring (c) and bent against its inside and rings (c) placed at the
inside of these ends for the purpose of firmly holding the paddles in position.
Dated this 5th day of March 1894.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.