| 摘要 |
A heavy duty expansible junction box hanger assembly adapted for installation from beneath a ceiling through a junction-box aperture in the ceiling without complete prior removal of a previously installed light-weight hanger assembly. The portion of the light-weight hanger directly above the aperture is cut away, and the heavy duty hanger is maneuvered through the aperture to a position above the light-weight hanger. A pair of feet on each end of the heavy duty hanger straddle the light-weight hanger and rest on the upper ceiling surface, aligning the heavy duty hanger parallel to the ceiling, after which joist engagement means on the hanger assembly are expanded into biting contact with the joists. |
