Tidal Mo′tor.
An arrangement by which the ebb and flow of the tide is utilized as a source of power to move machinery, etc. The idea is not new, and various devices have been invented for accomplishing the object.
A common mode is to place gates at the mouth of inlets which are opened during the flood and closed at the commencement of ebb tide; the head of water thus obtained is used to turn a mill-wheel.
Signor Thomassi has proposed to use the rise of the tide as a means of compressing air in a chamber or reservoir, from which the air thus compressed may be conducted to any number of stationary engines, the effective power thus obtained being proportional to the excess of its tension over that of the atmospheric pressure; this may be greater or less in proportion to the relative contents of the chamber into which the water is admitted, and that in which the air is condensed.
By an additional chamber, in which a partial vacuum is produced by the reflux of the tide, a continuous motor is produced, the effective force in this case being equal to the excess of atmospheric pressure over that of the rarefied air in the chamber.
See also sluice.
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Tide-gage. |
Scharit's tidal motor consists of a float, with a screw and valves for filling the float with water.
The float consists of a rectangular box made water-tight, and provided with valves for the admission of water when the flat has reached its highest point.
To the float a nut is attached, which works upon the screw and imparts thereto a rotary motion, which is communicated to the machinery to be driven by means of bevel-gears, one of which is attached to the top of the screw.
A continuous motion in one direction is secured by a ratchet and pawl, which are attached to the horizontal shaft that is placed directly over the center of the screw.
Modifications of this device have double racks working in pinions for communicating power, and a single rack for the same purpose; another modification has ropes or chains working on pulleys.
