PERFORATED WINDOW COVERINGS

摘要

2050314 9110804 PCTABS00006 Light admitting window coverings are provided with apertures (36, 38) which are formed in a covering such as a vertical blind louver (18). The louver is formed of opposed panel portions with a transparent film or sheet sandwiched therebetween to provide for sufficient light transmission and visibility through the louvers in the closed position but without permitting convective heat transmission through the window covering. The blind louvers may be formed with an insulating air space (64, 66) between the opposed louver panel portions and the transparent film or sheet. The blind louvers or single panel apertured blind louvers and the like may be formed with apertures at an acute angle extending downward towards the airspace formed between a windowpane and the window covering to minimze convective air flow from the room interior into the space between the window and the blind louver when the room temperature exceeds the outside ambient temperature and to prevent heat buildup in the space between the window coverings and the windowpane when the temperature in the room interior air space is less than the temperature in the airspace between the window covering and the windowpane.