Overview

A Gravity Limit Switch is a vital safety and control device used in EOT cranes, hoists, and winches to automatically limit the motion of the lifting or travel mechanism. It prevents the crane hook or load from moving beyond the pre-set upper or lower limit, ensuring safe and reliable operation. The switch is called “gravity type” because it functions through a mechanical weight and lever system, which operates by the force of gravity rather than springs.

This makes it highly reliable, low-maintenance, and durable, even in heavy-duty industrial environments.

Key Features

• Enhanced Safety: Prevents over-travel of hoist and crane hook.

• Gravity-Operated Mechanism: Reliable functioning without spring failure.

• Sturdy Construction: Built for harsh industrial conditions and long life.

• Smooth Operation: Ensures accurate stop points every time.

• Low Maintenance: Simple design with minimal wear and tear.

How It Works

The Gravity Limit Switch operates on a simple mechanical principle:

• A weighted lever is attached to a rotating shaft driven by the movement of the crane or hoist drum.

• As the drum rotates and reaches the set limit (up or down), the lever moves due to the gravity-based mechanism.

• The lever’s movement activates internal electrical contacts, which either cut off or reverse the motor circuit.

• This stops the motion of the crane or hoist, preventing over-lifting or over-lowering of the load.

Because it relies on gravity instead of spring tension, it ensures consistent operation even after long-term use.