Crane Damping System Using Additional Hydraulic Unit
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing crane systems experience long-duration oscillatory motions and hydraulic clearance issues, particularly when starting up with cold hydraulic oil, which can lead to unsafe conditions and reduced crane structure lifespan due to increased deflection and amplitude of movements.
Innovation Solution
A system comprising an additional hydraulic unit connected to the crane's hydraulic actuators, providing an additional hydraulic oil flow to dampen motion and increase stiffness, controlled by a pressure-reducing valve and sensors to optimize damping based on parameters like temperature, inclination, and load position.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional hydraulic systems are used without additional damping, then the system is simple and cost-effective, but the oscillation duration becomes excessively long (15-25 seconds) causing unsafe situations and reduced productivity
Solution Approach 1:
An additional hydraulic unit is introduced as an intermediary component between the main hydraulic system and the actuator. This intermediate unit provides dedicated damping functionality through its own hydraulic circuit, allowing oscillation control without modifying the main hydraulic system's core operation. The additional unit acts as a mediator that absorbs and dissipates oscillatory energy while maintaining the simplicity of the primary system.
Solution Approach 2:
The invention utilizes hydraulic principles by introducing an additional hydraulic unit with its own hydraulic oil flow path. This unit employs hydraulic resistance and fluid dynamics to create damping effects, converting the mechanical oscillation energy into hydraulic pressure variations that are dissipated through the hydraulic circuit, thereby reducing oscillation duration.
2Use of energy by moving object
If hydraulic oil volume is reduced due to low temperature, then energy consumption decreases, but hydraulic clearance increases causing difficult control and reduced reliability
Solution Approach 1:
The additional hydraulic unit is activated in advance during cold startup conditions to compensate for the reduced volume of hydraulic oil in the main system. By providing additional damping and stiffness through the secondary hydraulic circuit, the system pre-adjusts for the expected control difficulties caused by thermal contraction, maintaining reliable operation despite temperature variations.
Solution Approach 2:
The invention changes the hydraulic system's operational parameters by introducing a second hydraulic circuit with different flow characteristics. The additional unit modifies the overall system stiffness and damping parameters, compensating for the parameter changes (volume reduction) that occur in the main hydraulic oil due to low temperature, thereby maintaining consistent control precision.
3Adaptability or versatility
If the crane structure allows large amplitude movements, then the working range increases, but the deflection increases reducing the fatigue strength and lifespan
Solution Approach 1:
The additional hydraulic unit provides dynamic damping that adapts to the crane's operational state. During large amplitude movements, the damping force increases to limit deflection and protect the structure, while allowing the full working range to be utilized. The system dynamically adjusts the damping characteristics based on the oscillation conditions, maintaining both adaptability and structural protection.
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 solution effectively reduces oscillation duration and amplitude, enhancing crane stability and extending the lifespan of crane structures by minimizing hydraulic clearance and ensuring smooth operation across varying conditions.
Implementation Method 1
the additional hydraulic unit is configured to deliver an additional hydraulic oil flow and hereby damp the motion of the at least one hydraulic actuator
Implementation Method 2
When the oil passes the flow limiter, a turbulent flow in the oil is generated, whereby the hydraulic energy in the system is converted to heat
Data Source
Figure 1A~1B
Figure 2A~2B
Figure 3A~3B
AI summary
A system (2) for damping undesired oscillations in a movably arranged crane structure (4) is disclosed. The crane structure (4) is hydraulically driven by means of an arrangement comprising at least one hydraulic actuator (10, 10', 60) mechanically connected to an engagement structure (6) attached to the crane structure (4). The at least one hydraulic actuator (10, 10', 60) is in fluid communication with a hydraulic unit (16) through one or more conduits (14, 14', 64, 66). The hydraulic unit (16) is connected to a hydraulic pressure source (30). The hydraulic unit (16) comprises a valve (108) configured to direct hydraulic oil from the hydraulic pressure source (30), to the at least one hydraulic actuator (10, 10', 60). The system (2) comprises a damping member (3) comprising an additional hydraulic unit (40) hydraulically connected to a hydraulic pressure source (30) and to the at least one hydraulic actuator (10, 10', 60). The additional hydraulic unit (40) is configured to deliver an additional hydraulic oil flow and hereby damp the motion of the at least one hydraulic actuator (10, 10', 60) and accordingly damp the oscillations in the crane structure (4).