IMPROVEMENTS IN WATER WHEELS
Year: 1876

page_text: PROVISIONAL SPECIFICATION left by George Wilkins Clark at the Office of
the Commissioners of Patents on the 23rd May 1876.
GEORGE WILKINS CLARK, of the Iron Works, Henley-on-Thames, in the County
of Oxford, Engineer and Millwright. "IMPROVEMENTS IN WATER WHEELS."
My Invention relates to improvements in water wheels, and is designed to obviate
the difficulty heretofore occasioned by floods or excess of water in the working of
those water wheels termed breast wheels and undershot wheels. These wheels aro
moved by the dynamic force of water acting in the case of the breast wheel on
the floats of the wheel at a point between the horizontal plane of its axis and the
bottom of the wheel, and in the case of the undershot wheel in the floats at the
bottom of the wheel. The power or useful effect developed by these wheels is greatly
impaired at times by reason of the impossibility of mantaining a uniform level of
water in the watercourse in which they are placed, as an undue height of the tail
water produces a resistance or back pressure upon the floats which in some instances
renders the wheel totally inoperative.
These wheels have heretofore been constructed with the floats fixed rigidly or
immovably upon the circular frames or shroudings of the wheel. Consequently they
maintain one constant angular position during the revolutions of the wheel and have
to lift the tail water in rising through the same.
But according to my Invention I construct a water wheel with hinged or folding
floats so arranged upon and connected with the circular frames or shroudings of the
wheel that they open or unfold to receive the pressure of the water in the direction of
the wheel's rotation and fold or close upon the frames as they leave the water, so that
however deep the water may be they will rise through the same without any back
pressure or resistance.
"
To carry my said Invention into practice I hinge or pivot the floats to "starts
similar to those employed for holding the ordinary fixed floats of these wheels. The
hinges are preferably long flat bars with eyes for the hinge pins, and to which the
float boards are secured by bolts and nuts. At the back of the said hinges I form
projecting arms arranged to form stops which permit the floats to open and expose
their surface fully to the action of the water as they enter the same at the front of
the wheel and to hold the said floats in this position until they begin to rise out of
the water. The said floats then close or fold upon the frame by their own weight,
and as they leave the water lie nearly flush with the periphery of the frame. I
prefer to provide these stops with strips of wood or other suitable material at the
part which comes in contact with the frame to prevent any noise from their action.
Price 11

page_text: I may modify my Invention by forming and arranging the said hinges and stops
somewhat differently to those above described. Or I may adopt other suitable
means for securing the hinges or pivots upon the frame of the wheel, but in all cases
the floats must be so hinged or pivoted and provided with stops that they open and
remain open while passing through the water downward and under the wheel and 5
close or fold inward as they leave the water.