Improvements in Water Wheels,
Year: 1893

page_text: Date of Application, 9th Oct., 1893
Complete Specification Left, 29 h June, 1894-Accepted, 18th Aug., 1894
PROVISIONAL SPECIFICATION.
Improvements in Water Wheels,
I, CHARLES ALEXANDER SCHARFF, of San Francisco, U.S.A. at present of
26 Wiesenhuttenplatz Frankfort on the Main, Germany, Engineer, do hereby
declare the nature of this invention to be as follows:-
"
My invention relates to that description of water wheel known as the "Pelton
water wheel, in which bucket-shaped blades are subjected to the momentum of
a jet of water projected against them with considerable force. The present
improvements relate more particularly to the manner of fixing the said bucket
shaped blades to the rim of the wheel, and to the form and arrangement of these
buckets.
In the Pelton water wheel the buckets are fixed by screws or rivets, at certain
intervals apart, to the rim of the wheel. By the considerable force of impact of
the water jet upon the buckets the bolts securing them are subject to a great
shearing strain, whereby the buckets easily get loose and frequently break off
altogether. Furthermore, the useful effect of such wheels is reduced by reason
of the pressure exerted by the jet upon the frout surface of the bucket, as this
passes through the jet. This pressure causes a considerable resistance to the
entrance of the bucket into the jet, which acts contrary to operative effect of the
wheel.
My present improvements obviate these defects and increase the useful effect of
the water wheel.
For this purpose the flanges of the buckets by which they are fixed to the rim of
the wheel are made of such an extended segmental or curved shape that the flange
of each bucket butts closely against the edges of the flanges of the contiguous
buckets, so as to constitute together a second continuous rim round the wheel,
and thus the tangential strain to which each individual bucket is subjected by
the water jet is entirely taken by the abutment of the flange against the con-
tiguous one, so that the bolts or rivets are entirely relieved of the shearing
strain, and the fracture of the part of the plates through which they pass is
prevented.
Such extended flanges can either be formed in one casting with the buckets,
or they may be made as separate filling-pieces between smaller flanges on the
buckets.
As in the existing Pelton wheel, the buckets are made with a projecting angular
ridge at their middle, which divides the jet into two parts that pass round the two
cup-shaped parts of the bucket and escape at the sides thereof, but instead of the
bucket presenting to the jet a perfectly closed front side, as it passes through the
jet, and so causing the above mentioned detrimental resistance, the front side is
notched out at the middle to an extent corresponding to the diameter of the jet, so
that this can pass through the front side and impinge directly upon the front end
of the before mentioned angular ridge, which is thus exposed, and the front edge of
which is also made sharp or chisel shaped so as still further to reduce the
detrimental resistance to the jet's action.
Dated this 9th day of October 1893.
ABEL & IMKAI,
Agents for the Applicant.

page_text: I, CHARLES ALEXANDER SCHARFF of San Francisco, U.S.A. at present of
26 Wiesenhuttenplatz Frankfort on the Main, 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 :-
دو
My invention relates to that description of water wheel known as the "Pelton
water wheel, in which bucket-shaped blades are subjected to the momentum of
a jet of water projected against them with considerable force. The present
improvements relate more particularly to the manner of fixing the said bucket
shaped blades to the rim of the wheel, and to the form and arrangement of these
buckets.
In the Pelton water wheel the buckets are fixed by screws or rivets, at certain
intervals apart to the rim of the wheel. By the considerable force of impact of
the water jet upon the buckets the bolts securing them are subject to a great
shearing strain, whereby the buckets easily get loose and frequently break off
altogether. Furthermore, the useful effect of such wheels is reduced by reason
of the pressure exerted by the jet upon the front surface of the bucket, as this
passes through the jet. This pressure causes a considerable resistance to the
entrance of the bucket into the jet, which acts contrary to operative effect of the
wheel.
My present improvements obviate these defects and increase the useful effect of
the water wheel.
My improved construction is shewn on the accompanying drawing in which
Fig. 1. shews a part sectional side view of a water wheel, Fig. 2 shews a cross
section on line X-Y Fig. 1, giving a plan view of one of the buckets, and Fig. 3
shews a front view.
The wheel A has fixed to its rim a the buckets B so arranged that their extended
bases b butt against each other, being formed as segments of a complete circle
covering the rim of the wheel.
By this means the tangential pressure exercised by the water jet is distributed
through the bases of all the buckets and thus any shearing of the fixing bolts c or
breakage of the plates through which they pass, is prevented, as they are almost
entirely relieved of strain. The extensions of the bases b for the above purpose
may either be cast in one with the buckets, or they may be made as separate
intermediate pieces.
The buckets B are constructed, as in the existing "Pelton" wheel, with a pro-
jecting angular ridge at the middle, which divides the water jet into two parts
which pass round the two cup shaped parts of the bucket and escape at the sides
thereof, but instead of the bucket presenting to the jet a perfectly closed front side
as it passes through the jet, as is the case with the "Pelton" wheel, and so causing
the above mentioned detrimental resistance, the front side is notched out at the
middle, as shewn, to an extent corresponding to the diameter of the jet, so that
this can pass through the front side and impinge directly upon the front end g
of the ridge, this end being furthermore made as a chisel edge so as to enable
it to cut readily through the jet, thereby still further reducing the detrimental
resistance to rotation.

page_text: 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 :-
1. In a "Pelton" water wheel, driven by one or more jets, constructing the
buckets in such manner, that the bases thereof constitute segments of a com
plete circle so that the strain due to the impact to which a bucket is subjected
by the water jet is transmitted by the base to the bases of the preceding
buckets or to the intermediate filling pieces between these, substantially as
described.
"
2. In a "Pelton water wheel driven by one or more jets, constructing the
buckets in such manner that the front side thereof is formed with a notch or
opening in order to prevent loss of useful effect by the impact of the jet upon such
side, while the exposed end g of the ridge d is formed with a chisel edge, for the-
same purpose, substantially as described.
Dated this 29th day of June 1894.
ABEL & IMRAY,
Agents for the Applicant.