Solar motor

A steam generator derives solar energy by means of a plastic Fresnel lens mounted in a movable framework to follow the sun by means of a manually movable mechanism attached to the steam generator housing.

This invention relates to a solar motor with an optical radiation collector 
directed toward the sun and focussed upon a steam generator, or the like. 
BACKGROUND OF THE INVENTION 
Particularly in the regions near the equator, it has long been attempted to 
use sun rays as an energy source. Already power stations working with 
solar energy have been built and equipped with gigantic mirrors. For 
example, one use of solar energy for direct drive of smaller appliances 
such as irrigation pumps, has not yet been successful, since the necessary 
optical equipment, such as mirrors, spherical lenses, and the like, are 
expensive, sensitive and heavy. 
OBJECTS AND FEATURES WITH BRIEF DESCRIPTION 
An object of the invention therefore is to produce a solar motor of the 
aforementioned kind which is inexpensive, easy to operate and very strong. 
In accordance with the invention these problems are solved by a radiation 
collector consisting of a Fresnel lens, preferably plastic, which covers 
the steam generator framework. A Fresnel lens, or stepped lens, has the 
advantage that it is in a single plane, and the stepped surface can be 
simply made in a known manner. In particular, with regard to the 
construction of this lens from plastic, no particular requirement on the 
precision of the lens need be set. Then the cost of the lens is, for 
example, many times smaller than the cost of a spherical glass collecting 
lens of the same diameter. Also, the plastic stepped lens is considerably 
lighter than a comparable spherical glass lens, so that simpler production 
is afforded. 
In accordance with a specially suitable embodiment of the invention the 
Fresnel lens is put together in more than one part, preferably sectors. By 
employment of a special holder, if necessary with a support grating, the 
parts may be fitted together, to further reduce the production cost, and 
also the replacement of a damaged single part is simple. 
Briefly, in accordance with this invention, the solar motor with its 
weight, its simpleness in maintenance and its ruggedness in regions near 
the equator is suited as drive means for small and medium sized equipment, 
especially for irrigation pump stations or electric current generators and 
in some cases even for heaters. 
THE DRAWINGS 
In the drawings an embodiment of the invention is set forth, wherein: 
FIG. 1 is a schematic view of the Fresnel lens employed in the invention, 
and 
FIG. 2 is a perspective view of the solar motor.

In accordance with FIG. 1, the Fresnel lens comprises a thin sheet 10, on 
which is seen at the upper surface the desired refraction producing steps 
10a. The lens could be constructed out of glass or similar transparent 
plastic. Precision of the steps 10a is not a special requirement, nor is 
an optical diagram, but rather only the concentration of the rays at a 
focus point to provide a heating spot. The incoming light rays 11 are 
diffracted by the Fresnel lens 10 so that the diffracted rays 12 are 
focussed at heating spot 13. 
In FIG. 2, 14 identifies a motor housing, which has in its upper portion a 
steam boiler 15, in its mid part a steam turbine and in its lower part a 
pump (not shown). A horizontal traverse bar 16 is fastened to the motor 
housing, along which a cable 17 moves a carriage 18. On the carriage 18 is 
pivoted by one end a link 19, which is pivoted on the other end to crank 
arm 20. This crank arm 20 is pivoted in its middle to the motor housing 14 
and carries on the one extension to which the link 19 is fixed a 
counterweight 21, and on its other extension a frame 22 in which a Fresnel 
lens 10 according to FIG. 1 is affixed. Through pipe 23 the pump is 
coupled for transmission of water to sprinkler 24. 
By the manual movement of carriage 18 the Fresnel lens 10 can be adjusted 
so that it is directed toward the sun. This adjustment means is sufficient 
in general, but it is also possible to provide a further adjustment means 
to rotate the pump housing with light in the vertical plane. The sun's 
rays will be directed by Fresnel lens 10 toward the housing portion 15a of 
the steam boiler 15 to heat the water therein. The housing portion 15a 
will be continuously heated and is made of non-reflecting heat conductive 
material. The steam from boiler 15 then drives the steam turbine which in 
turn drives the pump. 
As previously explained, the Fresnel lens 10 can be put together from 
several sectors; and therefore frame 22 preferably has a grating support 
for holding the lens. It is therefore not necessary to provide the lens in 
a single piece. 
It is to be understood that the invention can have several modifications, 
especially relating to the equipment moving the frame 22. Also, the 
invention is not restricted to an irrigation station, but for example also 
may be used for electric current, heating and the like.