Movable support mechanism for construction of elevator shafts and the like

摘要

The invention also contemplates a retractable corner mechanism for the inside corner of the concrete form. The mechanism comprises an elongated corner member having first and second perpendicular faces joined along a first edge of each face to form a corner and having form attaching means along a second edge. A concrete form has an end attached to each of the second edges. Means are provided for sliding the forms relative to the corner member and means is provided for retracting and extending the forms to cause the corner member to be retracted and extended. The forms can be made of plywood or metal and the use of steel is contemplated for the corner members. The retracting and extending means can include an externally threaded rod pivotally connected adjacent the end of one of the concrete forms and an internally threaded member pivotally connected adjacent the end of the other of the concrete forms and treadably received on the rod. Means is provided for rotating the threaded member on the rod to retract or extend the concrete forms.