Ball Screw Intermediate Bush for Compact Linear Travel
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing ball screw designs face limitations in achieving large threaded spindle travel with a compact design, as they often require complex mounting and torque transmission, and struggle to efficiently convert rotational movements into pure linear movements.
Innovation Solution
A ball screw design featuring an intermediate bush with opposing threaded arrangements between the threaded nut and spindle, allowing for a telescopic mounting and direct motor-driven rotation of the intermediate bush to convert into linear movement of the threaded spindle, with a compact structure and optimized torque introduction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If a conventional ball screw design is used, then the structure is simple, but the threaded spindle travel is limited and the design is not compact
Solution Approach 1:
The intermediate bush is inserted into the threaded nut, and the threaded spindle is inserted into the intermediate bush, creating a nested structure where components are placed inside one another. This nesting arrangement allows the threaded spindle to achieve large travel distance while maintaining a compact overall structure, as the moving components are contained within the housing of other components.
Solution Approach 2:
The ball screw is divided into multiple functional segments: the threaded nut, the intermediate bush with opposing threaded arrangements, and the threaded spindle. The intermediate bush acts as a separate segment that provides two opposing threaded arrangements, enabling the threaded spindle to move linearly while the intermediate bush rotates, thus achieving large travel in a compact design.
2Length of moving object
If an intermediate bush with opposing threaded arrangements is used, then large travel with compact design is achieved, but the device complexity increases
Solution Approach 1:
The intermediate bush serves multiple functions: it acts as a structural connector between the threaded nut and spindle, provides a rotating mounting for the threaded spindle, and contains the second threaded arrangement for linear movement conversion. This multi-functionality reduces the need for separate components, thereby limiting the increase in device complexity despite achieving large travel with compact design.
3Manufacturing precision
If the intermediate bush is driven with rotary movement, then pure linear movement of the threaded spindle is achieved, but torque transmission requirements increase
Solution Approach 1:
The opposing threaded arrangements on the intermediate bush convert rotational movement into linear movement through the helical curvature of the threads. As the intermediate bush rotates, the rolling bodies travel along the curved thread paths, transforming the rotary motion into precise linear displacement of the threaded spindle, thereby achieving high manufacturing precision.
Solution Approach 2:
The intermediate bush acts as an intermediary component that receives rotary movement (either from direct motor drive or from the threaded nut rotation) and converts it into linear movement of the threaded spindle. This intermediary function allows for optimized torque introduction and transmission, as the intermediate bush can be directly coupled to the drive motor, eliminating the need for complex mounting and torque transmission mechanisms.
4Reliability
If rolling bodies are guided in thread channels of the intermediate bush, then wear is minimized, but the manufacturing complexity increases
Solution Approach 1:
The rolling bodies automatically return from the end of the thread channels to the starting point through the return channels formed in the intermediate bush, without requiring external intervention or complex return mechanisms. This self-service feature minimizes wear on the rolling bodies and thread channels while maintaining relatively simple manufacturing, as the return path is integrated into the bush structure.
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 design enables large threaded spindle travel with a compact structure, allowing for high force transmission and precise linear movement without the need for additional mounting, while minimizing wear and maintaining a compact form factor.
Implementation Method 1
rolling bodies are guided in these thread channels
Implementation Method 2
A rotational movement of the intermediate bush can be converted with a corresponding thread configuration into a pure linear movement of the threaded spindle
Data Source
AI summary
A ball screw comprising a threaded nut with thread channels for rolling bodies, a threaded spindle with thread channels for rolling bodies, and an intermediate bush, which is arranged between the threaded nut and the threaded spindle, wherein the intermediate bush has thread channels, which face the threaded nut and are adapted to the thread channels of the threaded nut, and rolling bodies are guided in these thread channels, and wherein the intermediate bush has thread channels, which face the threaded spindle and are adapted to its thread channels, and rolling bodies are guided in these thread channels, is proposed, wherein a first threaded arrangement, which is formed by means of the thread channels of the threaded nut and the intermediate bush facing one another, and a second threaded arrangement, which is formed by means of the thread channels of the intermediate bush and the threaded spindle facing one another, operate in opposite directions.