Abstract: A dual ratchet pawl jacking system, device, and method are presented for raising and/or lowering a platform bearing carriage along a vertical support. The ratchet pawls alternate supporting the weight of the carriage by engaging against a series of lugs on the vertical support. A first pawl is attached to the main frame of the carriage, and a second pawl is attached to a sub-carriage assembly that slides upward and downward within the carriage frame. A hydraulic jack applies a force upon the sub-carriage, causing the sub-carriage to move within the frame. The weight of the carriage is alternately borne by each pawl as the other pawl is relocated to a new lug. A pair of triggers is used to retract the first pawl and second pawl from the support. The triggers may be enabled to facilitate lowering the carriage, or disabled to facilitate raising the carriage.

Abstract: A dual ratchet pawl jacking system, device, and method are presented for raising and/or lowering a platform bearing carriage along a vertical support. The ratchet pawls alternate supporting the weight of the carriage by engaging against a series of lugs on the vertical support. A first pawl is attached to the main frame of the carriage, and a second pawl is attached to a sub-carriage assembly that slides upward and downward within the carriage frame. A hydraulic jack applies a force upon the sub-carriage, causing the sub-carriage to move within the frame. The weight of the carriage is alternately borne by each pawl as the other pawl is relocated to a new lug. A pair of triggers is used to retract the first pawl and second pawl from the support. The triggers may be enabled to facilitate lowering the carriage, or disabled to facilitate raising the carriage.

Abstract: In the construction of tall concrete towers, a two part derrick is suspended by cables from the tower to the lower part of the derrick. The derrick is extended on hydraulic rams, raising its upper part and outside casting forms. A pulley system maintains a deck scaffold and inside forms at their original level during extension. Extension of the derrick slakens cables from the tower to the upper part of the derrick. These cables are disconnected from the tower and reconnected at a higher level. Outside forms are fixed, reinforcing steel set in place, and the derrick retracted, raising the deck scaffold and inside forms by the pulley system, and slacking the lower cables. The lower cables are disconnected from the tower and reconnected at a higher level. Inside forms are set and concrete is poured. The concrete sets and the procedure is repeated.The deck scaffold comprises radiating wooden beams with endpieces.