Fluid Line Plug-In Coupling With Low-Force Retaining Clip Assembly
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing fluid line plug-in couplings require high insertion force due to the spring force of the retaining clip, making assembly difficult, especially when the spring force is strong.
Innovation Solution
The coupling housing features two contact slopes that allow the spring legs to spread radially outward, generating a springback force to automatically slide back into the holding position, with a bolt mechanism that prevents initial sliding and allows easy positioning behind the coupling socket's collar, reducing assembly force.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the spring force of the retaining clip is increased to secure the coupling socket, then the reliability of the connection is improved, but the insertion force required during assembly increases
Solution Approach 1:
The retaining clip is pre-positioned in a retracted state by the bolt before the coupling socket is inserted. This preliminary action prepares the clip to engage the collar without requiring high insertion force, while still providing secure connection once engaged
Solution Approach 2:
The retaining clip transitions from a retracted state (when the bolt is in its first position) to an engaged state (when the bolt moves to its second position). This dynamic state change allows the clip to provide strong holding force after insertion while minimizing resistance during insertion
2Reliability
If the spring force of the retaining clip is increased to prevent axial separation, then the connection reliability is improved, but the assembly difficulty increases
Solution Approach 1:
The bolt performs a preliminary action by positioning the retaining clip in a retracted state before the coupling socket is inserted. This preliminary positioning ensures that the clip will engage smoothly during assembly while still providing reliable connection security after assembly is complete
Solution Approach 2:
The bolt acts as an intermediary mechanism that controls the state of the retaining clip. By moving the bolt between its first and second positions, the system mediates between the need for easy assembly (clip retracted) and reliable connection (clip engaged)
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 design minimizes the insertion force required during assembly and securely positions the retaining clip, reducing the assembly force to a low level while ensuring the coupling is locked against axial separation.
Implementation Method 1
a springback force being able to be generated in the spring limbs of the holding clip, which allows the holding clip to automatically slide back into the holding position
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a VDA plug-in coupling, comprising a coupling housing (1) and a coupling connecting piece (8). Said coupling housing and said coupling connecting piece can be secured against axial pulling apart by means of a holding clip (3). The problem addressed by the invention is to improve a plug-in connection of the type mentioned above in such a way that the plug-in force is minimized. Said problem is solved in that, before the assembly, spring legs (3B, 3C) of the holding clip can be spread open by means of running slants (2B, 2C) such that a retracting force acts on the holding clip (3). The sliding back of the holding clip (3) into the holding position thereof can be prevented by means of an axially slidable bar (5). The bar (5) can be axially slid by means of a coding projection (10) of the coupling connecting piece (8) during the insertion, whereby the blocking of the holding clip (3) against sliding back can be suspended. By means of the coding projection (10) of the coupling connecting piece (8), which is present by default, the bar (5) can be slid with low force such that the holding clip (3) can slide over the running slants (2B, 2C) into the holding position of the holding clip. The assembly force thus can be reduced to a very small magnitude.