Axial Piston Unit Linkage With Elastic Load Decoupling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Hydraulic work vehicles equipped with hydrostatic variable displacement axial piston units face issues with rigid mechanical linkages that increase force requirements and provide undesirable mechanical feedback, leading to engine stalling and inefficiency when load conditions change.
Innovation Solution
A displacement volume setting device with an elastic connecting element that decouples the input and output couplings when high loads exceed a threshold, allowing the tilt angle to adjust independently and maintain efficient engine operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If rigid mechanical linkage elements are used to connect the input device to the displacement element, then direct mechanical connection and precise control are achieved, but force requirements increase and mechanical feedback becomes undesirable
Solution Approach 1:
A torque arm is introduced as an intermediary element between the input device and the displacement element. This torque arm rotates about an axis and provides mechanical advantage, allowing the operator to control the displacement element with reduced force while maintaining direct mechanical connection and precise control.
Solution Approach 2:
The linkage system is made dynamic by allowing the torque arm to rotate about an axis rather than using a fixed rigid connection. This dynamic arrangement enables the system to adapt to varying load conditions, reducing the force required to hold the linkage in place while maintaining control authority.
2Ease of operation
If rigid linkage elements are used for displacement control, then direct control is maintained, but engine stalling occurs under increasing load conditions
Solution Approach 1:
The torque arm acts as a mediator that decouples the direct rigid connection between the input device and displacement element. Under increasing load, the torque arm can rotate independently, allowing the displacement element to adjust without forcing the engine into stalling conditions, thus maintaining reliability while preserving control.
Solution Approach 2:
The system allows changes in the torque arm's rotational position as a parameter adjustment mechanism. When load increases, the torque arm's position changes, which indirectly adjusts the displacement element's tilt angle to match load demands, preventing engine stalling while maintaining direct control capability.
3Object-generated harmful factors
If the tilt angle cannot adapt to new load situations, then mechanical feedback is reduced, but engine efficiency decreases and overload occurs
Solution Approach 1:
The torque arm creates a feedback mechanism where load changes on the displacement element cause rotational movement of the torque arm, which in turn adjusts the displacement element's tilt angle. This automatic feedback allows the system to adapt to load changes, maintaining engine efficiency and preventing overload without undesirable mechanical feedback to the input device.
Solution Approach 2:
The system becomes self-regulating through the torque arm mechanism. When load conditions change, the torque arm automatically adjusts the displacement element's tilt angle to match the new load requirements, allowing the hydrostatic unit to self-adapt without operator intervention, thereby maintaining engine efficiency and preventing overload conditions.
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
Prevents engine stalling and maintains efficient operation by allowing the tilt angle to adjust to changing loads, reducing torque requirements and providing smooth feedback to the operator.
Implementation Method 1
the connecting element is elastically deformable if a force resulting from a high-pressure level which is present at/in the hydrostatic variable displacement axial piston unit exceeds a predetermined threshold-value
Data Source
AI summary
A displacement volume setting device of a hydrostatic variable displacement axial piston unit includes an input device for providing a displacement command. Displacement volume adjusting means set the tilt angle of a displacement element according to the displacement command. A linkage element has an input coupling element connected to the input device, an output coupling element connected to the displacement volume adjusting means, and a connecting element. The input coupling element and the output coupling element are connected by the connecting element which is elastically deformable if a force resulting from the high pressure level present at the hydrostatic axial piston unit and acting on the output coupling element exceeds a predetermined threshold value. Also disclosed is a hydrostatic variable displacement axial piston unit.