Scroll Compressor Shaft Seal Structure for Larger Rear Bearings
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The integration of separate rear bearing and shaft seal structures in scroll compressors leads to damage when the rear bearing's outer diameter exceeds that of the shaft seal, causing fluid leakage and performance deterioration.
Innovation Solution
A scroll compressor design with a separate shaft seal and bearing, featuring a shaft seal fixing plate interposed between them, along with a recess and step shape configuration to stabilize the shaft seal and prevent contact damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the rear bearing outer diameter is increased to expand operation range, then the bearing capacity is improved, but the shaft seal comes into contact with bearing balls causing damage
Solution Approach 1:
A shaft seal fixing plate is introduced as an intermediary component between the shaft seal and the rear bearing. This fixing plate prevents the shaft seal from contacting the bearing balls by maintaining a controlled distance, thus resolving the conflict between using larger bearings for expanded operation range and preventing contact damage to the shaft seal and bearing
2Device complexity
If the rear bearing and shaft seal are integrated, then the structure is simplified, but the shaft seal cannot be properly positioned when bearing outer diameter exceeds seal outer diameter
Solution Approach 1:
The shaft seal fixing plate serves as a mediator that enables precise positioning of the shaft seal relative to the larger rear bearing. By providing a dedicated mounting surface and positioning features on the fixing plate, the shaft seal can be accurately positioned even when the bearing outer diameter exceeds the seal outer diameter, avoiding the need for integration while maintaining manufacturing precision
3Volume of moving object
If the shaft seal is disposed directly on the bearing, then the assembly is compact, but the shaft seal outer peripheral surface contacts bearing balls causing damage
Solution Approach 1:
The shaft seal fixing plate is positioned between the shaft seal and the rear bearing to prevent direct contact. This intermediary structure maintains a compact overall assembly while ensuring that the shaft seal outer peripheral surface does not contact the bearing balls, thus preserving the durability of both components
Data Source
AI summary
There is provided a scroll compressor capable of stopping breakage even when a rear bearing supporting a shaft has an outer diameter dimension larger than an outer diameter dimension of a shaft seal. The scroll compressor includes a rear bearing 18 press-fitted and fixed to the center casing 6 to support the shaft 14, and a shaft seal 58 disposed on the through hole 17 side of the rear bearing 18. A movable scroll 22 is revolved with respect to the fixed scroll 21. The rear bearing 18 has an outer diameter dimension larger than that of the shaft seal 58, and the shaft seal 58 has a separate structure from the rear bearing 18. Between the rear bearing 18 and the shaft seal 58, a shaft seal fixing plate 64 having a diameter larger than that of the shaft seal 58 is interposed.