Improvements in Turbines.
Year: 1894

page_text: Improvements in Turbines.
1, GEORGE MILTON HOPKINS, Gentleman, of 361 Broadway New York
City, in the County and State of New York, United States of America, do
hereby declare the nature of my 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 turbines and will be described with
reference to the accompanying drawings forming a part of this Specification,
in which similar letters of reference indicate corresponding parts in all the views.
Figure 1 is a front elevation of my improved turbine ;
Figure 2 is a face view of one half of the turbine wheel;
Figure 3 is a diametrical section of the wheel;
Figure 4 is a central longitudinal section of the nozzle ;
Figure 5 is a front elevation of the same;
Figure 6 is a rear elevation of the nozzle; and
Figure 7 is a longitudinal section of a double nozzle for a reversing turbine.
The object of my invention is to construct a turbine-to be used with steam, water,
or compressed air as the propelling force-which is formed with a smooth, uninter-
rupted exterior surface which will offer a minimum of resistance to the air, and in
which the nozzle through which the propelling medium is ejected will be partly
surrounded by the propelling wings.
My invention consists in a wheel having a smooth exterior, and an annular chamber
containing wings for receiving the impact of the propelling medium, and having a
central free space for the ejector nozzle. It also consists in a nozzle constructed to
project steam in a thin wide stream against the wings, and arranged to draw the
air from behind the nozzle by induction, and project it in a stream impinging
on the jet of steam. The invention also further consists in a double nozzle arranged
to discharge the propelling medium in either direction for the purpose of reversing
the turbine. It also further consists in a turbine formed of aluminum, for the
purpose of reducing the weight and facilitating the reversal of the turbine.
In describing my invention I shall refer to it as a steam turbine, although I do
not limit myself to the use of steam as a motive agent. I shall also describe the
turbine as having an annular space of circular cross section, for containing the steam
nozzle, but I do not confine myself to this particular form.
с
Upon the shaft A, journalled in the frame B, is mounted the turbine wheel C,
which is formed of two similar halves a a', each provided with a boss b, and having
a web e and rim d of approximately semi-elliptical form, the two halves a a' being
oppositely arranged with respect to each other and fastened upon the shaft by means
of the nut e which clamps the wheel against the collar formed on or attached to
the shaft. The semi-elliptical half rims d, when placed together, form a practically
elliptical rim, in the center of which is formed an annular space g of circular cross
section, and on opposite sides of the said annular space g. the rim is cut away by
means of a suitable milling cutter, leaving the inwardly-projecting wings h, which
extend from a point near the periphery of the wheel to a point within the annular
space g.
In cutting away the interior of the rim to form the wings h, intermediate wings h
are formed, which are shorter than the wings h and project inwardly from the outer
portion of the wheel. This arrangement will be followed in the construction of very
small turbines, but in larger turbines where the wings are more nearly parallel, the
intermediate wings ' may be omitted.

page_text: From the periphery of the turbine wheel down to the annular space is formed
a slot for receiving the plate D, which supports the nozzle E and the pipe A
The plate Dis rigidly supported in such relation to the wheel C, as to allow the
wheel to revolve freely without coming into contact with the plate. The nozzle E
is made aumular, with the steam space having an annular discharge opening m,
the steam space communicating with the pipe k. Within the annular steam
space is a longitudinal opening n, partly closed by a cone o. leaving an annular
space p, the cone being held in its position by distance pieces 7, and retained by
a bolt which passes through a cross bar a extending across the rear end of the
nozzle E.
Although I have fully shown but a single nozzle in the drawings, in practice the
turbine will have two or more nozzles, as indicated by dotted lines; and furthermore,
where it is desirable to reverse the turbine, the nozzle is made double, as shown in
Figure 7, having two supply pipes k, l, two annular steam spaces I, two aumular
discharge openings m m³ and two annular spaces pp. The annular spaces [l', m m³
and open in opposite directions.
Steam admitted to the nozzle E through the pipe k, enters the annular space 1,
and is distributed and discharged through the numular opening m, the discharge
opening being of such character as to give to the annular jet of steam a divergent
form, causing it to strike the wings. In issuing from the annular opening m, the
steam by induction draws air through the annular space p, thus withdrawing the air
from behind the nozzle and projecting it against the annular stream of steam.
This arrangement to a great extent removes the back pressure of air behind the
nozzle, and its projection in a stream more divergent than that of the steam causes
it to act to some extent as an abutment for the steam, for holding it against the
wings / አ.
When the turbine is to be made reversible, the double nozzle shown in Figure 7
is used and steam is admitted to one or the other of the parts of the nozzle according
to the direction in which the wheel is to revolve. To facilitate the reversal of the
turbine, the wheel of a reversible turbine is made of aluminum, thus reducing
the momentum of the wheel, so that it may be more readily stopped and started
in the opposite direction. Where the turbine is not intended to be reversible,
it is preferably made of bronze or some unoxidable material having sufficient
strength.
It will be seen that my improved turbine offers no roughness or projections on
the exterior to act upon the air and thus cause resistance. The wheel having
wings which are practically radial, and being provided with a peripheral groove
for the discharge of the contents of the hollow rim, when it revolves at a high
velocity a partial vacuum is formed by centrifugal force, which adds to the efficiency
of the turbine by removing air resistance. Centrifugal force also throws out every
particle of water resulting from the condensation of steam.
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. A turbine wheel, having a smooth uninterrupted exterior and provided with an
annular space having at the sides thereof, wings for receiving the impact of the
propelling medium, and a nozzle held wholly within the annular space, with its sides
surrounded by wings except at the point of support, and constructed to project a
thin, wide jet of steam against the wings, as specified.
2. The combination, with a wheel having a hollow rim with an annular space,
and wings projecting into the annular space and furnished with a groove
extending from the periphery of the wheel to the annular space, of an annular
nozzle supported within the annular space and provided with two concentric
annular apertures, one for projecting steain against the wings, and the other for the
passage of air from the rear to the front of the nozzle, as herein specified.
3. A turbine wheel formed of two similar halves both placed on the shaft and

page_text: oppositely arranged with respect to each other, the division line between the halves
being in the plane of rotation of the wheel, the said halves being mounted rigidly
on a shaft, in contact with each other, the complete wheel having a hollow rim with
inwardly-projecting wings, substantially as specified.
4. In a turbine, a wheel having a hollow rim provided with inwardly-projecting.
wings, and having a groove extending from the periphery of the wheel inwardly,
the groove being enlarged within the rim of the wheel, forming a passage for the
nozzle, a nozzle placed in the said passage and constructed to direct a thin stream
of steam against the wings, and furnished with an opening from front to rear for the
passage of any fluid or liquid from the rear of the nozzle to the front thereof, as
specified.
5. A turbine, formed of a wheel having a hollow rim with inwardly-projecting
wings, and provided with openings through the wings which form an annular
passage through the hollow wheel rim and wings contained thereby, the wheel
having a peripheral groove extending to and communicating with the annular
passage, and a nozzle supported within the annular passage of the wheel rim and
adapted to direct a jet of steam against the inwardly-projecting wings, substantially
as specified.
6. In a steam turbine, the combination with a wheel having a hollow rim with
inwardly-projecting wings, of an ejector nozzle placed within the hollow rim and
having two concentric annular openings, the outer one being for the discharge
of steam under pressure, and the inner one being for removing air, steam or
water from the rear of the nozzle on the ejector principle, substantially as
specified.
7. The combination, with a turbine wheel having a hollow rim containing
inwardly-projecting wings and provided with an annular passage parallel with the
plane of rotation, of an annular nozzle supported within the annular passage and
arranged to discharge a thin stream of steam in a direction tangential to the path
of the inner edges of the wings, substantially as specified.
Dated this 19th day of June 1894.
Dated this 19th day of June 1894.
G. M. HOPKINS,
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.