Automatic Slack Adjuster Assembly for Sealed One-Way Installation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional self-setting automatic slack adjusters (S-ASA) face issues with unequal fatigue life due to different assembly directions, increased exposure to dust and water leading to potential corrosion, and confusion during assembly, which affects their performance and reliability.
Innovation Solution
The design of a self-setting automatic slack adjuster assembly that can be assembled in the same direction for both left and right brake assemblies, with the front side protected by the brake chamber mounting bracket, minimizing exposure to dust and water, and maintaining consistent stress patterns for equal fatigue life.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the conventional S-ASA is assembled in different directions for left and right brake assemblies, then the assembly can accommodate both sides, but the fatigue life becomes unequal and assembly confusion occurs
Solution Approach 1:
The housing is designed with asymmetric features including a non-circular cross-section and positioned sealing elements that create a preferred assembly orientation. This asymmetry ensures the S-ASA can only be assembled in the correct orientation, guaranteeing equal fatigue life for both left and right brake assemblies while eliminating assembly confusion
Solution Approach 2:
Instead of designing the S-ASA to accommodate both assembly directions through symmetric features, the invention inverts the approach by designing it to only accommodate one specific direction through asymmetric features, thereby ensuring consistent stress patterns and fatigue life
2Device complexity
If the front side of S-ASA is exposed to the environment, then the assembly is simpler, but dust and water entry causes corrosion of internal parts
Solution Approach 1:
A flexible sealing lip is positioned within the housing to create a barrier that prevents dust and water from entering the internal components. This flexible membrane approach provides effective sealing while maintaining relative simplicity in the overall assembly structure
Solution Approach 2:
The sealing lip acts as an intermediary element between the external environment and the internal components of the S-ASA, blocking harmful factors (dust and water) from reaching sensitive parts while allowing the assembly to remain relatively simple
3Ease of operation
If the pinion assembly pushes the cover plate during worm shaft rotation, then the mechanism functions, but a potential leak path is created
Solution Approach 1:
The harmful interaction between the pinion assembly and cover plate is eliminated by redesigning the mechanism to remove the pushing action. The cover plate is repositioned or reconfigured so it is no longer subjected to lateral forces during operation, thereby eliminating the leak path while preserving the essential braking function
Data Source
AI summary
A self-setting automatic slack adjuster assembly as per FIG. 6) comprising a housing (2) which receives a worm shaft (3) in bore (a) of the housing (2) where the hexagon nut of the worm shaft (3) is in the right side of the assembly. A worm wheel (16) is assembled in the bore (b) of the housing (2) which meshes with the worm shaft (3). The bore (b) is perpendicular to the bore (a). The worm wheel (16) is inserted onto the S-cam shaft where S-cam shaft is coaxial with bore (b) of the housing, a clutch worm gear (4) is inserted into the bore (a) from the right side of the housing (2) which meshes with the serrations of the worm shaft (3), a bore (c) is present on the right side of the housing. A ratchet-pinion assembly (14) is inserted into bore (c) of the housing (2), the clutch worm screw (14b) of the ratchet pinion assembly (14) meshes with the clutch worm gear (4) and when the above slack adjuster is installed into the brake assembly, its cover plate assembly (19) faces the brake chamber mounting bracket and thus protected by direct exposure to the dust and water.