Ball Screw Support Devices with Speed-Controlled Synchronous Displacement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Long ball screws with a large slenderness ratio tend to experience gravity sag, degrading precision and service life, and existing support systems are structurally complex and costly to maintain.
Innovation Solution
A ball screw design featuring symmetrically arranged support devices with a speed-controlling unit comprising runner structures with driving and driven wheels of different diameters, allowing the nut base and bush seats to move at proportional displacement velocities for stable support, simplifying the structure and reducing maintenance costs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If the length of the screw is increased to achieve greater travel, then the transmission capability is improved, but gravity sag occurs due to the large slenderness ratio, degrading precision and service life
Solution Approach 1:
The support system is segmented into multiple support devices distributed along the screw length, with each device independently supporting the screw at specific locations. This segmentation allows the long screw to be divided into multiple shorter effective spans, reducing gravity-induced sag while maintaining overall transmission capability.
Solution Approach 2:
Support devices act as intermediary elements between the long screw and the transmission system. These intermediaries provide localized support to counteract gravity sag, enabling the screw to maintain precision over long lengths without requiring the entire screw to be uniformly rigid.
2Manufacturing precision
If support devices are added to prevent gravity sag, then transmission precision is improved, but the structure becomes complicated and maintenance costs increase
Solution Approach 1:
The complex pulley and link mechanism is extracted and replaced with a simplified support device structure. Each support device is designed as an independent, self-contained unit with a bush mounted on a support bracket, eliminating the need for complex interconnected mechanisms while maintaining the function of synchronous support.
Solution Approach 2:
The support devices are designed to be self-aligning and self-adjusting through the speed-controlling mechanism. The different diameters of driving and driven wheels automatically create the required speed differential, causing support devices to self-position at appropriate locations along the screw without requiring complex external control systems.
3Reliability
If synchronous displacement of support devices is achieved through complex pulley mechanisms, then support reliability is improved, but the structure becomes complicated and maintenance becomes costly
Solution Approach 1:
The synchronization mechanism utilizes parameter changes in wheel diameters to achieve the required speed differential. By designing driving and driven wheels with different diameters, the system automatically creates the necessary velocity ratio to maintain proper spacing between support devices during displacement, replacing complex mechanical linkages with a simple geometric parameter solution.
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 design ensures reliable support and maintains constant displacement precision, reducing maintenance costs and extending the service life of the ball screw by synchronizing the displacement of support devices and controlling the diameter ratio between driving and driven wheels.
Implementation Method 1
the support device having a bush that is fixed to a bush seat and slidably mounted around the screw
Implementation Method 2
the runner structure having a foundation on which a driving wheel and at least one driven wheel are rotatably and concentrically installed, the driving wheel having a diameter greater than a diameter of the driven wheel
Data Source
AI summary
A ball screw with support devices includes a nut base having two sides equipped with the support devices for preventing the screw from deflection. Two runner structures are provided near two ends of the screw. The runner structure includes a driving wheel and a driven wheel having different diameters and concentrically installed. The nut base is connected to the driving wheel via an active connecting element for driving the driving wheel to rotate. The driven wheel moves with the driving wheel and is connected to the support devices via passive connecting elements so that the support devices and the nut displace synchronously. By controlling a diameter ratio between the driving and driven wheels, the nut and the support devices displace with proportional speeds, thereby allowing the support devices to always stay at the two sides of the nut as designed and provide reliable support.