Rotating Shaft Cooling Flow Passage for Vacuum Seal Unit
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing workpiece transfer apparatuses face limitations in cooling efficiency due to the use of air as a coolant, and the use of liquid coolants like water is restricted by the twisting of cooling pipes during rotation, which restricts the angle of rotation of the workpiece transfer mechanism.
Innovation Solution
The apparatus incorporates a vacuum seal unit with a rotating shaft, support bearing portion, and annular seal members that define independent spaces and cooling flow passages, allowing coolant to circulate and flow through the rotating shaft without twisting, even during rotation, and includes a relief passage to manage coolant leakage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If air is used as a coolant in the cooling circuit, then the cooling system is simple, but the cooling effect is insufficient due to air's lower specific heat capacity compared to liquid coolants
Solution Approach 1:
The patent transitions from using air (gas) as a coolant to using liquid coolant through hydraulic cooling circuits. The cooling flow passages are designed to accommodate liquid coolant flow, utilizing the higher specific heat capacity of liquids to improve cooling effectiveness while maintaining system functionality.
2Temperature
If a cooling pipe is routed from a pump into and out of the workpiece transfer mechanism inside a rotating shaft, then liquid coolant can be used to improve cooling effect, but the cooling pipe twists when the rotating shaft rotates, restricting the angle of rotation
Solution Approach 1:
The cooling circuit is segmented into multiple independent flow passages (first cooling flow passage, second cooling flow passage, third cooling flow passage) rather than using a single continuous pipe. This segmentation allows each passage to be independently routed and sealed, preventing twisting constraints on rotation while maintaining liquid coolant flow paths.
Solution Approach 2:
The cooling flow passages are nested within the rotating shaft structure, with passages routed through the shaft body itself rather than through external flexible piping. The passages are integrated into the shaft's internal structure, allowing the shaft to rotate freely without twisting external connections.
3Reliability
If multiple annular seal members are disposed between the rotating shaft and support bearing portion to seal gaps, then vacuum sealing is improved, but the structure becomes more complex with multiple seal members and independent spaces
Solution Approach 1:
The sealing system is divided into multiple annular seal members (first, second, third seal members) positioned at different locations along the rotating shaft. Each seal member creates independent sealed spaces (first, second, third spaces), allowing vacuum sealing to be maintained at multiple points simultaneously, improving overall sealing reliability.
Solution Approach 2:
The multiple annular seal members act as intermediary elements between the rotating shaft and the support bearing portion, creating sealed barriers that prevent vacuum leakage. Each seal member serves as an intermediate sealing interface, with the spaces between them providing additional sealing zones.
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 configuration enhances cooling efficiency using liquid coolants like water while preventing restrictions on the angle of rotation and minimizing vacuum leakage, ensuring effective cooling and operational flexibility.
Implementation Method 1
a cooling flow passage through which a coolant flows, the cooling flow passage being formed so as to circulate through inside the rotating shaft and inside the workpiece transfer mechanism
Implementation Method 2
the coolant introduced into the second space to flow through the cooling flow passage and to reach the first space
Data Source
AI summary
The vacuum seal unit of a workpiece transfer apparatus includes a plurality of seal rings and a cooling flow passage formed so as to circulate through inside a rotating shaft and a workpiece transfer mechanism. The seal rings adjacent to each other with a spacing therebetween, out of the plurality of seal rings, and the rotating shaft define a first space and a second space independent from each other and respectively surrounding the periphery of the rotating shaft. An end portion of the cooling flow passage communicates with the first space, and the other end of the cooling flow passage communicates with the second space. Even when the rotating shaft is rotating about the axial center, a coolant supplied to the second space can flow through the cooling flow passage and be supplied to the first space, thereby enabling cooling with high efficiency without restriction on the angle of rotation.