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TECHNIQUE FOR PREVENTING TOWER HOIST SWAY

IP.com Disclosure Number: IPCOM000235904D
Publication Date: 2014-Mar-28
Document File: 5 page(s) / 113K

Publishing Venue

The IP.com Prior Art Database

Abstract

The invention proposes a technique for protecting tower hoist sway. The technique avoids lateral movement of hoist by using a pulley type connection at down tower assembly (DTA) manually or motor driven. This is implemented by a chain hoist configuration. The lateral movement of the chain is minimized by creating a tension in the cable by pulley connection below the DTA platform driven by motor or manually. Retractable wire rope system is connected to the hoist hook for carrying the material bag.

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TECHNIQUE FOR PREVENTING TOWER HOIST SWAY

BACKGROUND

The present invention generally relates to wind turbines and more particularly to a technique for protecting tower hoist sway.

In general, tower hoist assembly is used to carry materials from tower bottom to top.

Figure 1 depicts conventional hoist hook movement system.

Figure 1

As illustrated in the figure above, the hoist hook is attached with a chain. The hoist hook is operated with a wireless remote control. When hook is lowered, the hook moves laterally due to tower vibrator. As a result, the tower shell is damaged. Sometimes, the hoist assembly is obstructed at the platform because of lateral movement. If the hoist assembly is continued to operate and the chain is lowered, the hook remains at the same vertical level for some time. The hook and connected chain drops in uncontrolled way through multiple levels of the hoist hatch corridor and service persons are injured. Another reason for the lateral movement of hoist hook is that the width of the chain holding drum is around 200mm. While the hook is lowered, the hook moves laterally due to dynamic movement after the drum is released.

A conventional technique provides a hoist system to raise a wind turbine component up to or down from a nacelle of wind turbine. The nacelle of the wind turbine has an opening in the lower part. A winch cable is guided through the nacelle by a deflection roller which is attached to the wind turbine component. The component is raised or lowered through the nacelle opening by a winch. However, the technique is not able to minimize lateral movement of the deflection roller.

Therefore there is a need in the art for a technique which minimizes lateral movement of the hoist hook.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 depicts conventional hoist hook movement system

Figure 2 depicts proposed technique to avoid tower hoist sway.

Figure 3 depicts rope hoist hook.

Figure 4 depicts chain hoist hook.

DETAILED DESCRIPTION

The invention proposes a technique for protecting tower hoist sway.

 

Figure 2 depicts proposed technique to avoid tower hoist sway.

Figure 2

As illustrated in the figu...