Operator`s manual

4.3 LADDER LOCKING PAWL ASSEMBLY
4.3.1 General
The ladder is equipped with a Locking Pawl Assembly which is designed to take the weight off the cables
when the ladder is extended. The pawl mechanisms are controlled by an operating lever located on
ladder Section 1. The lever is connected to the Locking Pawl Assembly by a series of cables and pulleys
(see Figure 4-16).
4.3.2 Description
The number references in brackets in the following description refer to the call-outs on Figure 4-16. For
the sake of simplicity, only one Locking Pawl and Locking Lever are illustrated. For a view of the complete
Locking Pawl Assembly, refer to the ladder parts list in Part 3.
When the Operating Lever (1) is down, i.e., the lever handle is parallel with the rails of ladder Section 1,
the cable is pulled taught and the Locking Pawls are disengaged and are stored in their own ladder
section.
When the Operating Lever is lifted, i.e., the handle is vertical to the rails of ladder Section 1 (1 dotted line),
the cable (12) is released from tension. The cable is fastened to the Lock Balancer (4) which rotates
under pressure of the Locking Pawl spring rearward, thereby allowing the Wire Lever (10) on Section 1,
which is fastened to the Pawl Shaft (9), to rotate downward. The downward movement of the Wire Lever
allows the spring loaded Locking Pawls (8) to swing up from their stored position in Section 1 and project
between the rails of ladder Section 2, above. The Locking Pawls are positioned to engage a rung of the
ladder section above by two Locking Levers (7). The position of the Locking Levers can be adjusted by
loosening cap screws.
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