Large Rolling Bearing Actuator With Annular Channel Cylinder
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current slewing bearing actuators face issues with non-constant adjustment torque, direction-dependent force, lubrication problems, and difficult maintenance due to large size and weight, particularly in wind turbines, where dismantling and reassembly are challenging and sub-component replacement is problematic.
Innovation Solution
Integration of an annular channel cylinder within one bearing ring, allowing the piston to move in a circular path without changing the lever arm, ensuring constant torque and actuating force in any direction, with flexible drive connections to compensate for bearing play and facilitate maintenance without complete dismantling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If a hydraulic cylinder with piston rod is used for adjusting the rotational position, then the actuator can generate adjustment torque, but the torque is not constant because the lever arm changes with the swivel angle
Solution Approach 1:
The patent applies the curvature principle by using an annular channel cylinder where the piston moves along a circular arc path instead of a linear path. The piston is connected to a pivot arm that rotates about a pivot point, and the piston's circular motion ensures that the lever arm distance from the pivot point to the actuation point remains constant throughout the rotation, thereby maintaining constant torque output regardless of the swivel angle.
2Force
If a hydraulic cylinder with different piston area and piston rod area is used, then the cylinder can function, but the cylinder force depends on the direction
Solution Approach 1:
The annular channel cylinder design with circular piston path ensures that the piston always acts at the same radial distance from the pivot point. This geometric configuration makes the lever arm constant in both directions of rotation, allowing the cylinder to generate equal magnitude forces in both clockwise and counter-clockwise directions, thus achieving direction-independent actuating force.
3Volume of moving object
If the actuator is integrated into the large diameter bearing, then the overall size is reduced, but dismantling and maintenance becomes more difficult
Solution Approach 1:
The patent applies segmentation by dividing the bearing structure into separable components. The inner ring and outer ring are designed as separate parts that can be disassembled from each other, and the annular channel cylinder is integrated into one ring but can be accessed and maintained when the rings are separated. This modular segmentation allows maintenance of the actuator without requiring complete dismantling of the entire bearing assembly.
Solution Approach 2:
The actuator components, particularly the annular channel cylinder and piston, are designed to be extractable from the bearing structure. The piston can be removed from the annular channel cylinder, and the cylinder itself can be accessed by separating the bearing rings, allowing maintenance and replacement of actuator sub-components without removing the entire bearing from the application.
4Duration of action of stationary object
If the bearing rings are kept in position for a long time, then the actuator remains stationary, but lubrication problems occur as lubricant cannot be distributed
Solution Approach 1:
The patent applies self-service through the automatic lubrication system that uses the piston's own movement to distribute lubricant. When the piston moves, even small distances, lubricant is automatically pumped through channels in the piston and annular channel cylinder to lubricate the contact surfaces. This self-lubricating mechanism ensures continuous lubrication without requiring external lubrication systems or manual intervention, maintaining reliability even during extended stationary periods.
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
The solution provides a compact, easy-to-maintain actuator with constant and direction-independent actuating torque, reduces wear-related issues, and allows for sub-component replacement without full disassembly, enhancing the reliability and efficiency of slewing bearings in applications like wind turbines.
Implementation Method 1
a piston (13, 14) which is slidably received in the annular channel cylinder (12)
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present invention relates to an adjusting drive for adjusting the rotational position of a large rolling bearing that comprises two bearing rings that can be rotated relative to each other, having an actuator for rotating the two bearing rings relative to each other. According to the invention, the actuating drive has a ring channel cylinder, which is formed in or on one of the bearing rings of the large rolling bearing, and at least one piston, which is received in the ring channel cylinder in a movable manner and is drivingly connected to the other bearing ring of the two bearing rings.