Patent Abstract:
Solar heat structure comprising a solar collector which may be parabolic and a diffusing element positioned axially of the solar collector for diffusing the sun&#39;s rays in the collector to thereby increase the heat collected by the solar collector for any given quantity of sun rays directed thereto.

Full Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to solar heat structures and refers more specifically to a solar collector and a diffusing element positioned centrally of the collector for increasing the heat collected by the solar collector. 
     2. Description of the Prior Art 
     In the past, solar heat structures have usually included some type of solar collector for absorbing heat in accordance with the sun&#39;s rays striking the solar collector. No prior means for diffusing the sun&#39;s rays in the solar collector to enhance the heat collected by the collector from the sun&#39;s rays in known. 
     SUMMARY OF THE INVENTION 
     In particular, the invention is the provision of a diffusing member centrally of a solar collector having reflecting elements whereby sun rays passing into the collector and/or reflecting therefrom are again reflected and diffused within the collector whereby the amount of heat absorbed by the collector for a given quantity of sun rays directed thereto is increased. 
     In particular, the diffuser of the invention is in the general shape of a Christmas tree having a central trunk or axis with reflecting fingers or branches extending outwardly from the axis thereof. The outer ends of the reflecting fingers of the upper portion of the diffuser define an angle of between 30° and 60° with respect to the axis of the diffuser. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a longitudinal section view of solar heat structure constructed in accordance with the invention including a parabolic solar collector having a diffuser secured therein axially thereof. 
     FIG. 2 is a top view of the solar heat structure illustrated in FIG. 1, taken substantially in the direction of arrow 2 in FIG. 1. 
     FIG. 3 is a longitudinal section view of modified solar heat structure constructed in accordance with the invention including a parabolic solar collector as shown in FIG. 1 and a modified diffuser secured to the collector axially thereof. 
     FIG. 4 is an enlarged, partly broken away section view of the solar heat structure shown in FIG. 4, taken substantially on the line 4--4 in FIG. 3. 
     FIG. 5 is a section view of the solar heat structure illustrated in FIG. 4, taken substantially on the line 5--5 in FIG. 4. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     As shown in FIGS. 1 and 2, the solar heat structure 10 includes a parabolic solar collector 12 and a diffuser 14 secured to the parabolic collector 12 on the axis of generation 16 thereof. 
     More particularly, the parabolic solar collector 12 may be constructed of aluminum or other metal and is provided with a dark, heat absorbing inner surface 18. The parabolic solar collector 12 has a focus 20 on the axis of generation 16 thereof, as shown in FIG. 1. 
     The function of the solar collector 12 is to absorb heat on receiving sun rays directed into the solar collector. To this end, if the material of which the solar collector 12 is constructed is not such as to provide a heat absorbing surface 18, during manufacture of the solar collector the surface 18 may be painted with for example a black and/or rough and low-reflecting surface for maximum heat absorption. 
     The diffuser 14 as shown in FIGS. 1 and 2 is a metal tube 22, 0.375 inches in diameter ±0.002 inches and 0.03125 inches in thickness ±0.002 inches, having angularly and axially spaced apart transverse openings 24 therein. The diffuser 14 is completed by placing a plurality of strips of metal foil such as aluminum foil 26 through the transverse openings 24 in the tube 22. The metal foil strips are 0.015625 inches thick ±0.002 inches and are cut and positioned in the tube 22 so that the completed diffuser 14 resembles a Christmas tree having sides which make an angle of between 30° and 60° with respect to the central axis of the diffuser except at the bottom thereof where the foil strips are terminated at approximately equal distances from the surface 18 of the collector 12. 
     The diffuser 14 is secured to the solar collector 12 with the axis of the tube 22 congruent with the axis of generation of the solar collector 12 by convenient means such as an adhesive securing the end 28 of the tube 22 to the solar collector 12, as shown in FIG. 1. 
     The diffuser 14 increases the heat collected by the solar collector 12. The diffuser 14 causes diffusion of the sun&#39;s rays within the collector and thus maintains sun rays which might otherwise be reflected from the solar collector 12 within the solar collector for a longer period of time than would be the case without the diffuser 14 in the collector 12. 
     Thus, for example, in a particular solar heater device, as disclosed in copending application Attorney Case No. 54,199, a diffuser constructed in accordance with the present invention was placed in the collector in the upper right hand corner of the solar heater and a 15° temperature rise in the collector in the solar heater at the upper right hand corner of the solar heater was recorded in thirty minutes. There was no noticeable change in temperature in the collector at the upper left hand corner of the solar heater. Subsequently, the diffuser was placed in the center collector in the third row from the top of the solar heater and an increase in temperature of 58° at the collector with the diffuser therein was recorded in one and one-half hours. Such test results show the value of a diffuser constructed as shown and described and positioned in a solar collector axially thereof in collecting heat due to solar radiation for use in solar heaters and the like. 
     In a modification of the invention, as shown for example in FIGS. 3 and 4, the solar heat structure 30 again includes a collector 32 and a diffuser 34. The collector 32, as before, is parabolic, has an axis of generation 36, a focus 37 and has a heat absorbing surface 38. 
     The diffuser 34, as best shown in FIGS. 4 and 5, includes a cylindrical rod 40 which may be of aluminum or other metal and which has a reduced diameter threaded end 42. As shown in FIG. 4, the reduced diameter threaded end 42 of the rod 40 is passed through an opening 44 in the parabolic solar collector 32 with the rod 40 extending on the axis of generation of the solar collector 32 and the rod is secured to the collector 32 by means of the nut 46 and washer 48. 
     Reflecting members 50, as best shown in FIG. 5, are constructed of reflecting material such as metal or metal foil in the shape shown having four or six reflecting finger portions 52. The reflecting members 50, as shown, are provided with an opening 54 centrally thereof and are sleeved over the rod 40. 
     As shown best in FIG. 4, the reflecting members 50 are spaced axially on the rod 40 by means of short spacing tubes 56. The reflecting member 50 closest to the end 58 of the diffuser 34 is secured in axial position on the rod 40 against a spacing tube 56 by convenient means such as the dished fastener 60. As before, the reflecting fingers 50 are terminated to form a Christmas tree like structure of the diffuser terminating at the focus 37 of the collector as shown best in FIG. 3. 
     In assembly with the parabolic solar collector 38, the diffuser 34 increases the heat absorbed from a given quantity of sun rays. As indicated above, it is believed that the added heat absorption by the solar collector is due to diffusion of sun rays within the solar collector so that the rays have a second, third, fourth, etc., reflection onto the surface 38 of the solar collector 32. 
     While one embodiment of the invention, together with one modification thereof, have been considered in detail, it will be understood that other embodiments and modifications thereof are contemplated by the inventor. It is the intention to include all embodiments and modifications as are defined by the appended claims within the scope of the invention.

Technology Classification (CPC): 5