How Mobile Cranes Power Their Upper Parts Using The Lower Base

A design for mobile construction cranes that moves the power generator to the base while keeping the control electronics separate and protected.

What it covers

This patent describes a way to power the heavy-duty components of a construction crane—like the hoisting winch, trolley drive, and lights—by placing the electrical generator in the crane's undercarriage rather than the top superstructure. Crucially, it requires the 'switchgear cabinet' (the box containing the generator's control electronics) to be physically separated from the generator itself, but still located on the undercarriage. This setup uses a rotary union to pass power from the base up to the rotating top part, allowing the crane to operate efficiently while keeping sensitive electronic controls away from the vibration and heat of the generator.

What it doesn't cover

• —Does not cover cranes where the power generator is located in the top superstructure.
• —Does not cover systems where the switchgear cabinet is integrated into the same physical housing as the generator.
• —Does not cover stationary tower cranes that lack an undercarriage.

The clever bit

The innovation is the physical decoupling of the generator from its control cabinet within the undercarriage, which allows for better vibration isolation and heat management of sensitive electronics without sacrificing the power-to-weight benefits of the base-mounted generator.

Why it matters

Mobile cranes are complex machines that must balance weight and stability while rotating. By centralizing power generation in the base, manufacturers can reduce the weight of the crane's upper section, which improves stability and lifting capacity. This design also makes maintenance easier by grouping power components in the undercarriage.

Real-world examples

• 1.Liebherr mobile construction cranes
• 2.Large-scale mobile tower cranes used in urban construction