Apparatus for concentrating solar radiation with inflatable concentrator cushion

The invention discloses an apparatus for concentrating solar radiation with inflatable concentrator cushion. The apparatus is provided for concentrating solar radiation in an absorber (1'), with an inflatable concentrator cushion (2) which has a covering foil element (3'') with a transparent inlet window (3) for letting solar radiation in and a reflector foil (6), dividing the concentrator cushion (2) into at least two cavities (4, 5), for concentrating the solar radiation in an absorber (1'), with a pivoting device (7) by means of which the concentrator cushion (2) can be pivoted, in particular about its longitudinal axis, and with a holding device (31), attached to the pivoting device, for holding the concentrator cushion (2), which holding device (31) has an upper longitudinal beam (32), extending in the longitudinal direction of the concentrator cushion (2), for hanging the absorber (1'), wherein the upper longitudinal beam (32) is arranged at an essentially airtight closed upper passage opening (34) of t