A ladder hoist is a device used to lift heavy objects on a platform mounted to a ladder, which is usually made of aluminum. Roofers and other laborers who commonly work on roofs or other high places will use the ladder hoist to safely transport heavy items which would otherwise need to be hauled up the ladder by hand. The hoist itself is usually motorized for further convenience and safety, though added weight to the ladder system. These machines are usually quite compact, making them easy to transport to different job sites.
An aluminum ladder frame is the key component to the entire system. This ladder must be rated to handle the added stress of the ladder hoist system, and most hoists of this design come with a ladder included to ensure the proper unit is used with the motorized platform. The platform is secured to the ladder, and it will travel along the vertical uprights of the ladder via a cable system or rack and pinion system that is controlled from the ground in most cases. The engine is mounted at the base of the ladder, adding convenience at maintenance time and further stability by adding weight to the base.
Controlling the ladder hoist requires a user to stand on the ground at the base of the ladder. A hand lever can be pushed downward to activate the ladder hoist system; the platform will rise up the ladder to a person standing at the top, waiting to receive the materials on the platform. Once the unit reaches the top of the ladder or the desired height, the operator on the ground can depress the hand lever, stopping the platform. Sometimes the ladder hoist is equipped with a braking system for added convenience and safety. Once the platform has been unloaded, the lever can be operated again, lowering the unit back to the ground.
Most hoist systems of this type use a pulley wheel mounted to the motor. A cable is wound around the pulley wheel, and when the wheel moves in one direction, the cable is released; when the wheel moves in the other direction, the cable is retracted. The cable will be strung from the motor pulley at the base all the way to the top of the ladder; it will then often pass through another pulley mounted at the top, and the cable will return to the bottom of the ladder where it will be attached to the platform.