Actuator Spring Assembly to Prevent Cover Thread Galling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In actuators, especially those with limited space, the inclusion of a biasing member can lead to increased dimensional envelopes and complex assembly challenges due to galling issues when using malleable materials like stainless steel, particularly in sanitary applications where space is constrained.
Innovation Solution
A method and apparatus that compress the biasing element inside the cavity, decoupling its force from the cover during assembly, using a compression assembly that positions the biasing element inside the cavity and maintains it in a compressed state, allowing the cover to be coupled without the biasing element's influence, thus preventing galling and enabling assembly with a smaller dimensional envelope.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a biasing member is included in the actuator to provide fail-safe functionality, then the reliability is improved, but the length of the actuator increases
Solution Approach 1:
The biasing element is nested within the cavity of the actuator housing, with its first end extending beyond the housing end in a relaxed state. When compressed, the biasing element fits within the cavity dimensions, allowing the actuator to maintain a compact length while still providing fail-safe functionality through the biasing element's presence and operation.
2Reliability
If a biasing member is included in the actuator to provide fail-safe functionality, then the reliability is improved, but the device complexity increases
Solution Approach 1:
The method performs preliminary compression of the biasing element before coupling the cover to the housing. The compression assembly pre-compresses the biasing element to a compressed state, positioning its first end inside the cavity before the cover is attached. This preliminary action prevents galling during assembly by ensuring the biasing element is already compressed and will not expand to engage with the cover threads during the coupling process.
Solution Approach 2:
The compression assembly acts as an intermediary device that temporarily holds and compresses the biasing element during assembly. This intermediary mechanism allows the biasing element to be maintained in a compressed state without direct engagement with the cover, simplifying the assembly process by preventing galling issues that would otherwise require complex anti-galling measures or procedures.
3Ease of manufacture
If the biasing element is allowed to engage the cover during assembly, then the assembly process is simpler, but galling damage occurs to the housing and cover
Solution Approach 1:
The compression assembly applies preliminary anti-action by compressing the biasing element before the cover coupling process begins. This pre-compression prevents the biasing element from expanding and engaging with the cover threads during assembly, thereby preventing galling damage to both the housing and cover while still allowing for a relatively simple assembly process.
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 approach effectively prevents damage from galling during assembly and disassembly, allowing for the use of actuators with small dimensional profiles while maintaining the fail-safe functionality, even in applications with limited space and using anti-corrosive materials like stainless steel.
Implementation Method 1
a spring positioned in the cavity in a relaxed state, the spring in the relaxed state having a second dimensional length that is greater than the first dimensional length of the cavity
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Methods and apparatus to assemble actuators are described. An example method includes positioning a biasing element in a cavity defined by a housing of an actuator such that the biasing element is in an uncompressed state and at least a portion of the biasing element is to extend outside of the cavity beyond an end defined by the housing; compressing the biasing element to a compressed state until the portion of the biasing element extending outside of the cavity is positioned inside the cavity; coupling a cover to the end of the housing to capture the biasing element in the cavity; and maintaining the biasing element in the compressed state during the coupling such that the biasing element does not engage the cover.