Open Ball Screw Nut With Two-Piece Circulator Assembly
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing ball screw assemblies face manufacturing precision issues due to sagging screws and complex manufacturing processes, particularly when using one-piece circulators, which lead to deflection and improper rolling of balls in the threaded groove.
Innovation Solution
A two-piece circulator structure is introduced, comprising an inner and outer member with corresponding through holes and slots, allowing for simplified assembly and manufacturing, and enabling the use of different materials for improved durability and cost-effectiveness, while facilitating ball filling without additional elements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a one-piece circulator structure is used, then the manufacturing process becomes simpler, but additional insertion members are required for mold formation which complicates the overall manufacturing process and module development
Solution Approach 1:
The circulator is divided into two separate pieces: an inner circulator and an outer circulator. This segmentation eliminates the need for additional insertion members in mold formation, as each piece can be manufactured independently using standard molding techniques. The inner circulator fits within the outer circulator, and both are assembled into the ball nut, simplifying the overall manufacturing process while maintaining structural integrity.
2Ease of operation
If the supporting holder is moved away from the screw using a resilient mechanism, then the ball nut can pass smoothly, but the screw portion may sag due to its weight causing deflection and improper ball rolling
Solution Approach 1:
The resilient mechanism is pre-configured on the supporting holder to automatically move it away from the screw when the ball nut approaches. This preliminary action prevents interference before it occurs, allowing smooth passage of the ball nut while the screw maintains its proper position and alignment throughout the process.
3Productivity
If a two-piece circulator structure is used, then assembly and manufacturing are simplified and materials can be optimized, but the structure becomes more complex
Solution Approach 1:
The circulator is segmented into an inner circulator and an outer circulator that can be manufactured separately using optimized materials for each component. The inner circulator can be made from a material suitable for high-wear contact areas, while the outer circulator uses a different material optimized for structural requirements. This segmentation improves assembly efficiency and material optimization while the modular design actually reduces overall complexity compared to a one-piece structure requiring insertion members.
Data Source
AI summary
An open nut and a ball screw assembly having the open nut are provided. The ball screw assembly includes a guider, an open nut, and a ball circulating assembly. The open nut includes an axial cylinder, an open shield, and two circulators. The two circulators are respectively disposed on a first axial wall and a second axial wall of the axial cylinder with an axial opening. Each of the circulators includes an inner member and an outer member. The inner member and the outer member are assembled to each other and are respectively in communication with an inner ball race between the guider and the open nut and an outer ball race of the open nut. Therefore, the inner ball race, ball races of the two circulators, and the outer ball race form a ball circulating race, and the ball circulating assembly rolls in the ball circulating race.