Linear Transmission Device Sensor Placement for Spacer Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional linear transmission devices face challenges in directly detecting changes in the distance between rolling elements, leading to increased complexity, cost, and potential machine shutdown due to spacer collapse or jamming, as existing sensing methods either lengthen the guide carriage, alter the nut's size, or require complex installation and limited stress detection.
Innovation Solution
A linear transmission device featuring an elongated shaft with a helical groove, a moving module with a rolling unit and spacers, a return assembly with sensors at the junction of pipes to detect distance changes between rolling elements, and a data receiving unit for signal processing, allowing for timely detection of spacer abnormalities without altering the device's structure or increasing size.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a sensor is installed on the guide carriage to detect displacement resistance, then abnormality detection capability is improved, but the length of the guide carriage increases
Solution Approach 1:
The sensor is extracted from the guide carriage structure and relocated to the return assembly. Specifically, the sensor is mounted on the return passage or return pipe rather than on the guide carriage body, thereby detecting rolling element abnormalities without increasing the guide carriage length.
Solution Approach 2:
The return assembly serves as an intermediary structure that carries the sensor close to the rolling elements without being part of the guide carriage. The sensor detects changes in the return passage caused by rolling element movement, indirectly monitoring the rolling elements while maintaining a compact guide carriage design.
2Measurement precision
If a sensing device is provided in the nut to measure ball displacement, then stress condition detection is improved, but the outer diameter of the nut increases
Solution Approach 1:
The sensing function is extracted from the nut structure and transferred to the return assembly. The sensor mounted on the return passage detects rolling element position changes through the return path, eliminating the need for embedded sensors within the nut that would increase its outer diameter.
Solution Approach 2:
Instead of measuring displacement radially within the nut (increasing outer diameter), the detection is performed axially through the return passage. The sensor monitors the position of rolling elements along the return path direction, utilizing a different spatial dimension for measurement.
3Reliability
If a vibration sensor is installed at the bend of the outer circulation member, then running condition detection is improved, but the device complexity and manufacturing cost increase
Solution Approach 1:
The return passage itself serves as the sensing medium. Changes in the rolling elements' condition directly affect the return passage geometry or position, which the sensor detects without requiring separate vibration sensing mechanisms or complex signal processing systems.
Solution Approach 2:
The complex vibration sensing system is replaced with a simpler direct detection method. Instead of using vibration sensors to indirectly infer running conditions, the patent uses a sensor that directly detects positional or geometric changes in the return passage caused by rolling element abnormalities.
4Reliability
If conventional sensing methods are used to detect ball stress, then stress change detection is possible, but direct measurement of distance change between balls is impossible
Solution Approach 1:
The return passage serves as an intermediary that transmits information about rolling element spacing to the sensor. By monitoring changes in the return passage geometry or position, the sensor indirectly but precisely measures the distance changes between rolling elements that cause spacer collapse or jamming.
Data Source
AI summary
A linear transmission device includes: an elongated shaft member, a moving module, a rolling unit, a return assembly, a sensor and a data receiving unit. The linear transmission device has a simple structure. The sensor is disposed at the junction of the first return pipe and the second return pipe of the return assembly to timely detect the change in the distance between the rolling elements, which can determine whether there is an abnormality in the shape of the spacers. With the sensor outputting detecting signals, it can stop the terminal immediately to confirm the condition of the workpieces and the machine, avoiding the structural damage of the machine and the workpiece caused by the continuous operation. The sensor can also serve as a medium for transferring data, further facilitating maintenance.