U-Shaped Counterweight Frame With Displaceable Plates

Solution Overview

Problem

Existing cranes with telescopic counterweight arrangements have limited adjustability, restricting the range in which the counterweight can be displaced relative to the axis of rotation, which limits the crane's stability and load handling capabilities.

Innovation Solution

A crane design featuring a U-shaped counterweight frame with independently longitudinally displaceable counterweight plates on side members, allowing the counterweight to be moved closer to the axis of rotation and providing a wider range of adjustability without the need for complex restacking of counterweight plates, and incorporating a support device for ground stabilization.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If the counterweight arrangement is telescoped out on existing carriers, then the counterweight moment can be adapted to different loads, but the adjustment range is limited to a small region behind the superstructure platform

Engineering Contradiction:

Core Design Contradiction:

Adaptability or versatilityVSLength of moving object

Solution Approach 1:

The counterweight plates are divided into two separate stacks, each independently displaceable on its own side member. This segmentation allows each stack to be adjusted independently, effectively doubling the adjustment range compared to a single centralized counterweight arrangement.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The counterweight plates are displaced along the side members (longitudinally) in addition to the telescopic movement of the counterweight frame. This adds a second dimension of adjustment, enabling the counterweight center of gravity to be positioned over a much wider area including regions close to the axis of rotation.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

2Reliability

If the counterweight plates are displaced close to the axis of rotation, then the ballast torque can be adjusted to exceed the load torque and prevent tilting, but the counterweight arrangement requires a wider displacement range

Engineering Contradiction:

Core Design Contradiction:

ReliabilityVSLength of moving object

Solution Approach 1:

By dividing the counterweight into two independently adjustable stacks on separate side members, the system can achieve greater total displacement range without requiring each individual component to be excessively long or complex.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The counterweight arrangement is made fully dynamic with both the counterweight frame telescopic and the counterweight plates longitudinally displaceable on side members. This multi-degree-of-freedom dynamic system allows the counterweight center of gravity to be positioned precisely at any location within the enlarged adjustment region, including close to the axis of rotation when needed for maximum stability.

Inventive Principle:

Principle #15Dynamics

3Adaptability or versatility

If a telescopic carrier is used to adjust the counterweight radius, then the counterweight moment can be adapted, but the adjustment is limited to a defined region and requires complex restacking for large adjustments

Engineering Contradiction:

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The counterweight plates are segmented into two independently displaceable stacks rather than a single fixed or telescopic unit. This allows continuous adjustment of the counterweight center of gravity position without requiring complex restacking mechanisms, as the independent displacement of the two stacks provides fine-grained control over the ballast torque.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The system transitions from static or limited telescopic adjustment to fully dynamic adjustment where counterweight plates can be continuously repositioned along side members. This dynamic capability eliminates the need for complex restacking operations while providing adaptability across a wide range of load conditions.

Inventive Principle:

Principle #15Dynamics

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This design enhances the adjustability of the counterweight arrangement, preventing tilting and ensuring a positive guying force, allowing for greater stability and load handling capacity without complex plate restacking, and allows for the ballast torque to be adjusted to exceed the load torque.

Implementation Method 1

The counterweight plates forming the counterweight are separated into two stacks which are each longitudinally displaceably guided independent of one another on a side member

Methodology Applied

Scientific EffectGravitation: Gravitation

Implementation Method 2

A U-shaped frame 21 which is articulated to the superstructure 2 about a luffing axis 22

Methodology Applied

Scientific EffectMechanical Advantage: Mechanical Advantage

Data Source

PatentUS9890020B2Crane, in particular derrick crane

Publication Date: 2018.02.13

AI summary

The present disclosure relates to a crane having a travelable undercarriage and a superstructure which is rotatably supported thereon, to which a boom is luffably connected in an articulated manner, on the one hand, and a counterweight arrangement is telescopically supported, on the other hand. In accordance with the present disclosure, the counterweight arrangement comprises a U-shaped frame in which a likewise U-shaped counterweight frame is telescopically guided. The counterweight plates forming the counterweight are separated into two stacks which are each longitudinally displaceably guided on a side member.